Abstracts Monday AM, April 7, 1997 Sessions 7, 8, and 11-15 7.1 ARE MEASUREMENTS OF LEFT VEN'f RICLILAR EJECTION FRACTION (LVEF) BY GATED SPECT THALLIUM-201 IMAGING REPRODUCIBLE? L. DeWalt, N. Nallamothu, E.R. Acio, J. Heo, A.E. Iskandrian, Allegheny University of the Health Sciences, Philadelphia, PA, USA A previous study using automated edge detection found a good correlation between LVEF measured by gated SPECT Tc99m sestamibi perfusion imaging and first-pass radionuclide angiography (RNA) (Germmao G, J NucI Med 1995;36:2138). This study examined the reproducibility of rids method using thallium-201 rather than Tc-labeled tracers in 32 patients (pts) aged 65+11 years (18 men and 14 women). Each pt underwent adenosine or dipyridamole gated SPECT thallium with reinjection imaging 4 hours later using ADAC cameracomputer system. The perfusion pattern was abnormal in 19 pts (18/19 had reversible or partially reversible defects). The gated LVEF was normal (>- 50%) in 22 pts and abnormal in 10 pts. There was an excellent agreement between post-stress LVEF and reinjection LVEF .(50+16% vs 50-+17%, r = 0.93, P<0.0001, SEE 6.2%). The image quality was good to excellent in all pts and the automated method appeared to track the endocardial borders in all pts. Regional dysfunction was present in 15 pts in both the post-stress images and in reinjection images (P:NS). Thus, using the software developed by Germano et al, reproducible measurements of LVEF can be made with gated SPECT flmllium-201. Such measurements may provide incremental diagnostic and prognostic information to perfusion imaging alone.

7.2 NEW COLOR MAP DISPLAY FOR EVALUATION OF DISSOCIATION B E T W E E N M Y O C A R D I A L FATTY METABOLISM AND MYOCARDIAL P E R F U S I O N H. Iwasaki,K.Iwata,M.Tuda,d.Ohno,i,, M.Kawamura. Cardiovascular center Owari Hospital Ichinomiya Aichi Japan Backqround:The findings of dissociation between myocardial fatty metabolism and myocardial perfusion include clinically important information. Conventionally, the discrepancies b e t w e e n 1231-1abeled 15-(P-io dop hen yl)-3-(R,S)-meth yl pentadecanoic acid (BMIPP) and 2mTICI are frequently observed, but the dissociations must be judged visually on the SPECT images or myocardial bull's eye's maps. But this method lacks objectivity and precision because of much differences in the characteristics of 2 nuclides, specially less TICI uptake in inferior wall.in this study we made a new myocardial color map to evaluate a dissociation between two nuclides objectively. Objectives and Methods:l) In twenty normal subjects without coronary disease, myocardial maps of 1231-BMIPPand 2O~TICIwere produced from SPECT images.And the mean value of the % uptake of distribution was calculated on each nuclide.2) Based on the ratio of the mean value, corrections were analyzed again in a new myocardial development chart. Results: In the normal subjects,the mean ratio of the mean % uptake for BMIPP to that for TICI was 0.92. The normal range(___SD<7%>) was established in this study. Conclusions: Our new map could display precisely area of dissociation between fatty metabolism and perfusion in myocardium and allows quantification of the extent and degree of dissociation.This maps are useful for evaluating the ischemic myocardium and the improvement of myocardium after revascularization.

Journal of Nuclear Cardiology January/February 1997, Part 2

7.3 I M P A C T O F B O D Y H A B I T U S ON A C C U R A C Y O F STANDARDIZED ATTENUATION CORRECTION RECONSTRUCTION MP White, DM Cross, A W Ahlberg, GV Heller. Hartford Hospital, University of Connecticut, Hartford, CT, USA. Fifteen patients (pts) referred for rest/stress SPECT myocm'dial perfusion imaging (MPI) were studied to deternaine if standardization of iterative reconstruction (IR) for attenuation correction (AC) is appropriate regardless of body habitus. Pts were injected with Tc99m Sestamibi at rest and peak stress and classified in three groups (40-89, 90-121, or 122+ kgs). Imaging was performed on an ADAC Vertex with Gd-153 scanning line sources. Data was processed and interpreted blinded with AC using twelve iterations and without AC and compared to cath. Results: Cardiac Catheterization (+) 40-89kgs 90-121kgs 122+kgs No AC 85 % 66 % 70 % With A C 50 % 100 % 90 % Conclusion: Standardized iterative reconstruction for attenuation correction may overcorrect defects in patients with small body habitus.

7.4 THE LABELING EFFICIENCY OF SESTAM/BI: A CONTROL BEYOND THE MAXIMUM TIME. M,Bagherkojasteh, R.Baravelti, L.Ferraguti, A.Barboni, S.Romani, N.Prandini, L.Feggi Nuclear Medicine Dept., Arcispedale S.Anna, Ferrara Italy The sestamibi is a cationic and lipophitic complex used for imaging of myocardium and in the search of tumors. This product is commonly distributed as lyophilized: It is reconstituted and labeled with 1-3 ml of 9~Tc-eluate (5,56 GBq). The productive (Dupont Pharma) guarantees a stability of bond for 6 hours at room temperature. The aim of our study has been to assess if sestamibi can be longer employed for example for urgent examinations, or for myocardial perfusion in single day protocol. The labelling efficiency (LE) was assessed in 13 vials of 99mTcSestamibi at 0.5 1, 2, 4, 6, 8, 10 and 24 hours after standard reconstitution. Some vials were conserved at 4 ° for avoid bacterial contamination: a total of 52 chrornatographies were achieved. The LE resulted acceptable in all controls with an average of 96.97% (4- 2.16). The chromatographic data remained acceptable after the time of expiry in all controls until 24 hours.

In conclusion Sestamibi could be effectively used longer than the maximum recommended of 6 hours: this can give advantage for the department in the management of urgent examinations with a saving of money.

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Journal of Nuclear Cardiology January/February 1997, Part 2

Abstracts

Monday morning,April 7, 1997 7.5 Tc-99mTETROFOSMIN: RADIOCHEMICAL PURITY AND STABILITY 24 HOURSAFTERRECONSTITUTION R. Casati. C. Sdraiati. R.Leo. F.R.Colombo. A.Bruno. R.Benti, P.Gerundini: Depa&ment of Nuclear Medicine - IRCCS - Ospedale Maggiore - Milano. Tc-99mTetrofosmin (Tf) (Myoview-Amersham Inter. plc) has to be stored at 2”-8°C after reconstitution and used within 8 hrs. Aim of this study was to define the radiochemical purity of Tf at room temperature (RT = 21”-25°C) and at 4’-5°C (refi.) till 24 hrs, in order to verify if the clinical use of the product is possible all over the day. The quality control of 14 preparations was performed at 0, 2, 8 and 24 hrs by thin layer chromatography (TLC), using ITLC-SG strips eluted with acetone/dichloromethane, 3.5165 (v/v), solvent mixture. Radiochemical Purity (R.P.) was measured as the percentage activity between Rf 0.2 and 0.8 referring to total activity of the strip, using a dedicated imaging scanner. Samples were spotted with 121.11of saline immediately followed by 2.5 ~1of Tf solution.

7.7 A STUDY OF THE EFFECT OF IMAGING PARAMETERS ON THE PROPAGATION OF NOISE w A CARDIAC MULTI-DETECTOR SPECT SYSTEM N.Baltani and P.H.Jarrilt. University of Surrey, Guildford and Institute of Nuclear Medicine, UCL, London, UK. t)To assessLhepropagation of noise in SPECT images using GE dual-head gamma camera (Opr1&1,4). 2)To study the cll’cct on signal-&noise ratio (S/N) of adding planar projection imaga prior Lo reconstruction or lhc rcconslruclcd images post rcconskuction. A conical shaped flask phantom Iiicd &h uniform solution of wTc’” was used. To assess reprcducibili~p, 32 scans were pcrcrlbnned for each variable using a multigatcd SPECl acquisition. Variables wcrc studied at diffcrcn~ count densities: 180” vs 360” sampling, number of projections and collimator type. Singlehcead and dual-head gamma cnmeras gave similar S/N, 107 and 112, respcctivcly, at 52 kcn&@rojection. For 180” versus 360”, there is a dccrcasein signal Lo noise ratio of to- 15% for the same count dewily. For adding at pre or post rewu.w-uction, measurementsof S/N show no sibtificant diffcrcnce for rcstoralion littering only. When smoothing filters are applied, the two methods divcrgc v& improvement in S/N for the adding of planar images prior Lo reconstruction. The reconstruction proccdurc followed by lhc dual-head detector d~n’l add noise Lothe SPECT images.

We conclude that radiochemical purity is independent of storage conditions till 24 hrs and > 90%.

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7.8

QUANTIFICATION OF SPECT MYOCARDIAL PERFUSION SCANS USING A POLAR MAP BUILT FROM RADIAL SLICES. T. Benoit, P. Rigo, J. Foulon, University of Liege, Belgium

CARDIAC VOLUMES MEASURED BY GATED PET IN NORMAL SUBJECTS H.L. Boyd, 0. Rimoldi, P.G. Camici. MRC-CSC and RPMS, Hammersmith Hospital, London, UK

We have developed a new software to build polar maps using radial slices. On a long axis image resulting, from summation of radial slices, we manually draw a region of interest to mask the extramyocardial activity. An ellipse is automatically fitted to the left ventricle (LV) in which the maxima corresponding to the LV contour at midwall are searched for. The rotation of a vector originating at each polar center of the ellipse or at points regularly spaced along the line joining these centers and the search on these vectors for the highest consecutive 5 points including the midwall point leads to the construction, for each radial slice, of an activity profile next transformed into a band. Rotation and summation of the bands generate the polar map. Data are corrected for surface distortion resulting from planar projection. Truncation of basal regions is based on a 60% isocontour of the appropriate mean normal database. We have constituted separate rest and stress data bases for women and men and for usual myocardial

tracers.

The average and minimum perfusion values are displayed into a 20 segments grid.The extent and severity of the defects are estimated only in regions where perfusion is lower than normal mean - 2.5 S.D. Finally, an hypoperfusion index is calculated by multiplying defect extent by its mean severity. Phantom studies have proven that this integral index is an excellent estimate of the true defect size.

The accuracy of left ventricular (LV) volume measurements based on geometric assumptions is dependent on an idealized ellipsoid model. This dependency hampers accurate measurements in those patients with distorted LV. This limitation is overcome by tomographic techniques. We have recentlv validated a method for the measurement of cardiac volumes and derived parameters using C”O and gated

positron emissiontomography (PET). The aim of this study was to assess end-systolic volume (ESV), end-diastolic

volume

(EDV), ejection fraction (EF) and cardiac output (CO) with

this method in a group of normals. Ten subjects underwent a 9 min scan (16 gates/cardiac cycle) after inhalation of 3

MBq/ml of CL’0 at 500 ml/min over 4 min using an ECAT 931:08/12.

EDV mean+SD 11I&19 Range XI-130

ESV 34*9 21-47

EDVIm’ 6129 47-6 I

ESV/m’ 1~935 12-28

EF% CO 7c+4 5.1+1 64-75 3.8-6.9

In conclusion: Our preliminary results show that PET measurements of cardiac volumes in normals are comuarabte to those in the literature. PET should also provide Fetiabte measurements of cardiac volumes in patients with distorted ventricles.

Journal of Nuclear Cardiology Volume 4, Number I, Part 2

Abstracts Monday morning, April 7, 1997

7.9

7.11

EVALUATION OF DISSOCIATION OF IODINE-123LABELED FATTY ACIDS AND FLOW TRACER ~gmMIBI IMAGES IN PATIENTS WHO UNDERWENT CORONARY ARTERY BYPASS GRAFTINGS H. Iwasaki,K. Iwata,M.Tuda,J. Ohno,F. Murakami,,M Kawamura. Cardiovascular center OwariHospital Ichinomiya Aichi Japan Backqround: Inthe hypoxic myocardium,fattyacids metabolism is inhibited and glucose metabolism increases,and clinically the dissociation between ~231-1abeled-15-(P-iodophenyt)-3-(R,Smethyl-pentadecanoic acid(BMIPP)and 99rn-Tc-sestamibi(MIBI) image is frequently observed. We investigated whether dissociation between BMIPP and MIBlimages before coronary artery bypass graftings (CABG) could be used in the prediction of improvement in myocardial fatty metabolism and perfusion after CABG. Ob}ectives and Methods: 1)Thirty of 73 patients who underwent CABG between May,1995 and April,1996 were studied. BMIPP and MIBlimages were performed under resting conditions pre and 1 month post CABG. Myocardial SPECT images were divided into 18 regions ,and scoring of the defect was done in terms of % uptake. 2)The patients were classified according to differences in the preoperative defect score into th re eg re up s, type B(BM IP P> MIB I), type E( BM IPP=M IB I),and typeM(BMIPP
TRUNCATION AND MISPOSITIONING: A PROBLEM IN MYOCARDIAL IMAGING WHEN USING A MOBILE TOMOGRAPHIC GAMMA CAMERA? M.Persson, D.Bone, S.Dale. Karolinska Institute, Stockholm, Sweden The aim of this study was to investigate the effects of truncation and misalignment of the detector head with respect to the left ventricle using a mobile gamma camera with a rotating slant hole technique - ectomography. Phantom studies were performed with 3 different slant hole collimators: a 40° 4 segment with four projection directions 90 ° apart, a 30° 2 segment and a 40 ° 1 segment collimator. The phantom consisited of a heart phantom positioned in a water filled perspex thorax (35x25x60 cm) containing lung equivalent material. A perfusion defect was simulated in the lateral inferior wall of the central section. Acquisitions were made with the detector head positioned to obtain an ideal acquisition geometry, a l0 ° misalignment in one and two directions and truncation of the base and apex, with and without external activity present. (300 ml of activity at 35% of the myocardial activity.) Results show that misalignment does not significantly affect the size and position of the defect in the reconstructed sections, neither does presence of external activity. Truncation effects of apical and basal regions do not propagate into non-truncated regions.

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7.12

INTLUENCE OF RECONSTRUCTION ARETFACTS ON ANTERIOR AND INFERIOR PERFUSION DEFECTS IN 99TCM PERFUSION IMAGING G.W.Middleton, J.H.Williams and A.C.Tweddel, University Hospital &Wales, Cardiff, UK. False defects in the anterior and inferior surfaces of the lett ventricle occur freqently using both 201T1 and 99Tom perfusion agents and are thought to be due to attenuation. 99Tcm perfusion agents enable 360 ° acquisition to be performed routinely using a single head 1 gamma camera. In 20 patients, stuffed us'm g 9 9 Tc m Tetrofosmin, data was acquired over a 360 ° rotation and reconstructed using both 180° and 360 ° data into the usual orthogonal slices through the heart. Significant areas of reduced/absent counts were noted adjacent to the heart on the transaxial, unzoomed body slices using t 80° compared with 360 ° data. These areas were more pronounced in cases with significant liver, gallbladder or bowel activity. The orthogonal sfices using 360 ° data showed reduced resolution and in the majority of cases, improved uptake in the anterior and inferior walls compared to 180° data. In summary, reconstruction artefacts using 180° data can result in false anterior and inferior perfusion defects. These can be minimised by using 360 ° data.

RESI'-STRESS fc-99 m SESTAMIBI SPECT ,'MYOCARDIAL I S C n E M I A INI)I'CED BY D O B U T k M I N E VS. DOBUTA.MINE AND ATROPINE E. ,-\lexandcrson. A Zajarlas. M. Zaragoza, I,. Crespo, D.Bialostozky, A. Puente, D. Victoria. Instituto Nacional de Cardiologia "tgnacio Ch-~vez". Mexico City, MEXICO,

Pl~annacdogical stress test with dobntamine induces ischemia in patients x~ith coronary artery disease(CAD). There is not consensus about the utility of the atropine associated with dobutarnine when the patient is unab]e to react~ the n~aximal heart rate. The aim of this study is to evaluate if the use of atropine associated with dobutamine induce ischemia in patients with CAD as well as if there are more side effects combining both drugs. METHOD: we studied 26 consecutive paticnts with CAD confirmed by coronay angiogram. Patients were divided in 2 groups: group A studied with pharmacological stress with dobutmnine and group I3 with 15 patients studied ~.ith dohutamine and atropine. We used continuous ml'usicm ol'dobutamino incrementing dosis ever3., 3 minutes: 5,10=20,30,40 mcgr/Kg-mm. Atropine ~as injected at dosis of 20 and 30 mcgr/kg/min of dohlaamine inlhsion if Ihe heart rate was under 100 beats per minute. Tc99 Sestamibi ~ a s n~jecled when the m a x i m a l heart rate was reached, and Ihe doblttalnille in[klsion \~,as inaintaincd 1 m o r e minute . RESUI,IS: A

D,')[a. TAM [NE INDUCliD WI'H 1OUq ISC) U¢'MjA INDUCED I3CIIEMIA I PRESbZ~I ~ I A ] } S E N ~ 2 Sensillvily 93%

B

I",\L3

[

DOBUTAMINIZ 4 ATROPIN~ INDUCED I WITHOUT ISCHEMIA ! INDUCED lSCHEMIA 14 } 0 ,~pecificit~ 88%

Group 13 reached 91% of die ma×imal heart rate calculated while 87.8% was reached in group A. Side effects were minimal and sitnilar in both groups,ocnmng in 40'% of file patients. CONCLUSIONS: Pharmacological stress test using dobutamine and atropine has a good sensitivitY for diagnosis of ischemia. The protocol is well tolerated, with minimal side effects and can be used as an alternative of pharmacological stress test in patienls unable to reach the maximal heart rate with dobutamine infusion.

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M O N D A Y A M A P R I L

Abstracts Monday morning, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

7.13

7.15

C O M P A R I S O N OF E X E R C I S E A N D D I P Y R I D A M O L E TC-99m T E T R O F O S M I N S C I N T I G R A P H Y F O R T H E D I A G N O S I S OF C O R O N A R Y A R T E R Y D I S E A S E IN PATIENTS W I T H L E F T B U N D L E B R A N C H B L O C K

ARTIFACT IN A PATIENT SUBMITTED TO PERFUSION MAG NG WITH 99mTc-TETROFOSMIN

Z. Yi~it, K. $i~li, T, G~irmen, M. Gtilbaran, V. Sansoy, D. G0zelsoy. Institute of Cardiology, University of lstanbul, Istanbul, Turkey It is well known that the specificity o f myocardial perfusion scintigraphy for the diagnosis of coronary artery disease (CAD) is low in patients with left bundle branch block (LBBB). It has been suggested that the use o f IV dipyridamole (Dp) instead of exercise as a stress modality increhses the diagnostic accuracy of the test. Accordingly, symptom-limited treadmill exercise and Dp Tc-99m tetrofosmin seintigraphies were performed in 30 consecutive patients with LBBB and chest pain. After the stress tests, all patients underwent coronary angiography. In 15 patients with CAD, significant perfusion defects were detected after exercise in 11 (73%) and after 1V Dp in 10 (67%), while of 15 patients with normal angiography, 2 (13%) displayed perfusion defects after exercise and 1 (6%) after DP. In conclusion, no difference was found between exercise and Dp Tc-99m tetrofosmin scintigraphies for the diagnosis of C A D in patients with LBBB.

MYOCARDIAL]

J

B. Madni, L. Guerra NuclearMedicineDepartment- San GerardoHospital- Monza IN.TRODUCTION It is known that the rapid hepatic clearanceof 99mTc-Tetrefosmin can reduce the interferenceof left liver lobe with inferior myocardialwall. The rapid clearance,on the other hand, causes the filling of gallbladder and this determinesan hot spot that sometimescan overcomethe myocardial activity. To obtainthe emptyingof gallbladderefat meatis raccomandedto the patient30 minutesbeforethe startof the examination. CASE REPORT A male patient 60 years old affected by angina was subm~ed to myocardial peffusion SPET to evaluatethe presence of coronary artery disease. The patientwas positiveat the stress-EKGwithoutsymptoms. In the clinical historyof the patientthere is a partialgastrectomyfor ulcer 14 years before. Myocardial perfusion imaging with 99mTc-tetrofosmin was negative for parfusicn defects, but the interpretation of images was difficult, in particular at the interiorand posteriorwall, becauseof the presence of an high activ'~ probablylocalizedin the gastric stump. The patientwas then submitted to chotescintigraphythat put in evidencethe presence of a consistentduodeno-gastricreflux. CONCLUSION The use of myocardial perfusion agents labelled with 99mTc needs an accurate collection of the clinical history to point out any conditions to correlate to the presence of dcodeno~estdc reflux. In this case the fat meal can handicap the interpretationof the images. During acquisition, in this patient, it is usefull a costant obseptationof the examinationby the technologistto put in evidenceabnormalgastricactivity.

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8.1

A NEW PF,RFUSION TECIINIQUE FOR TIIE EVALUATION OF THE RIGHT VENTRtCI,E D Victoria, Y Alex~tnderson, D Bialostozky, G Pozas, V.Ancona, A.Puente. Depanamento de CardioIogla Nuclear, Institute Nacional de Cardiolog/a "Ignacio Ch;ivez". MEXICO. INTRODUCTION:Due to the morfology and anatomic location of the RICHT ventricle (P,V) their study represent a tecnical problem. These is because of the bigger size of the left ventricle. Radionnclide uptake occurs mostty in cardiology, including Nuclear Cardiology. This structure making difficult the right ventricle visualization.This low radiommlide uptake bv the right ventricle maker more difficults the analysis of the RV perfusion and (nncfion OBJETIVES:In the actuallity does not exist an objective me0~od to know the severity, extension and localization of ischemic mid necrotic process of the right ventricle. For this reason we designed u tcchnnluc that permit the visualization in Ibnn independent of the Eight ventricle.METHOD:We have use a conventional tonmgraphic stn& to probe a new technique realizing an. clasic reconstructions, ~ill~ 32 stops in an arc the 180 degrees to obtain a right venlricle images in the short axis, long vertical axis and long horizontal axis.Wilh the right ventricle images in the short axis, we made a selection of the best one eta in with we can visualize the cavity and the content of the right ventricle. The left ventriclexhe extracardiac captation radioauclide activity is erased with the objetivc of increasing the right ventricle visualization.We made a selective elimination of one of all the taked images and automatically the computer erase the rest of the left ventricle dislortioaing images with pemfits the best rio~'ut'ventricle visualization.The anterior procedure is realized at rest and stress.To mlalize the obtained images the right ventricle is divided in 2 segments, basal and medial at the same time each one of this are subsecuently divided m 3 small areas wich correspends to the anterior, lateral and inferior righ vcnlriclc walls.We use a amneric scale of 5 points ( 0 = NOilmd to 4 ~ Abmncc captation ).CON(?I,I;SIONS:The menlional above technique hat, stl,mcd to l)¢ nimple and usethll to recognized right ventricle myocardial p,:rlhsi,n dc~:cts, including the dii]'~zvzntiationbetween ischemic and necroticlissue.

99m Tc-MIBI MYOCARDIAL PERFUSION IMAGING: NONINVASIVE DETECTION OF ENDOTHELIAL DYSFUNCTION. Samoylenko LE., Sergienko VB., Karpov YA., Sayutina EV., Soboleva GN., Samko AN., Matchin YG. Cardiology Research Center, Moscow, Russia Endothelial-dependent dilatation is impaired in men with risk factors for coronary artery disease, before anatomical evidence of plaque formation in the arteries appears. Endothelial dysfunction (ED) is known to be an early event in atherogenesis. Our study aimed to assess value of stress 99mTc-MIBI SPECT myocardial perfusion imaging for detection ED. The 8 patients (pts) with chest pain, risk factors for CAD and angiographically normal coronary arteries (NCA) were studied, Increasing concentrations of acethylcholine (Ach) (5x10-7,5x10-6,5x10 -5) were sequentially infused at 0.25 m/min,2.5 m/min and 25 m/min x2 rain into the left coronary artery. Of 8 pts 5 developed Ach-induced aradoxical constriction of coronary arteries (suggesting ED), 9mTc-MIBI was injected simultaneously with the last dose of Ach or when evidence of vasospasm appeared. SPECT myocardial perfusion imaging was performed within 1 hour. All pts underwent stress 99mTc-MIBI SPECT within 7 days. 5 of 8 pts had identical regions of perfusion defects both on intracoronary Ach test and stress test scintigrams. Our findings suggest that ED may contribute to ischemia-induced perfusion defects on stress scintigrams in patients with NCA & chest pain, risk factors for CAD.

~

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Monday morning, April 7, 1997

8.2

8.4

THE VALUE OF DIPYRIDAMOLE Tc-99m-MIBI SPECT IN CORONARY ARTERY DISEASE IN SELECTED CLINICAL SITUATIONS.COMPARISON WITHEXERCISETc-99m-MIBISPECT B.Szumilak.A.Tere~ifi.~ka,S.Konieczna,E.Go~iew~ha,L.M.Brodzki Instituteof Cardiology,Warsaw,Poland

MACHINE LEARNING IN THE DIAGNOSIS OF ISCHAEMIC HEART DISEASE C. Grogelj, M. Kukar, J.J. Fenich, I. Kononenko. University Medical Centre, Faculty of Computer and htformation Scicnce, Ljubljana, Slovenia Improvements and rationalisation of diagnostic procedures of ishaemic heart disease (IHD) would be very useful. The diagnostic process inchlding evaluation of symptoms and signs of the disease and ECG at rest, ECG during exercise, myocardial perfusion scintigraphy and coronary angiography is stepwise and the results are interpreted hierarchically, only the results of the highest step are valid. Machine Learning (ML) methods may be able of objective interpretation of all available results and in this way increase the diagnostic accuracy of each stcp. ML algorithms deal with inducing problem-specific knowledge from examples. Given a set of pre-classified examples, the ML algorithms are able to [earn the relation(s) between description and class of the example. The learned knowledge is presented in different forms (in our case as a decision tree) and can be used to classify new, previously unseen examples. In our case, each example represented a patient, who was classified according to the results of angiographic coronarography. Our goal was to predict the result of coronarography from signs, symptoms, and results of earlier tests (exercise ECG, myocardial scintigraphy) and evaluate the contribution of each test. We proved this hypothesis in a group of 326 persons with angiographically confirmed or excluded IHD. The sensitivity of stress myocardial scintigraphy was 83 and specificity 85. By using thc ML algorithm, we achieved sensitivity 89 and specificity 88 for the same set of data. In conclusion, the ML algorithm improves the diagnostic accuracy of stress myocardial scintigraphy for diagnosing IHD

The aim of the ~'tudywa~ to egtabli~h if the dipyridamole (Dip) SPECT bring tantamont irtfomaatiomabout perfu~iondefeet~ to exercise (Exl SPECT in patienti (pt~)withcoronaryarterydisease(CAD)in ~eleetedetinieal ~ituatior~. 105 pts were examined: 39 with one coronary artery occluded: 24 of them with collateral circulation(group .1), 15 pl~ withoutcollateral circulation(grot,.'p 11); 35pN withCAD withLBBB(group 111) and 31 pt~ withCAD and infarct(group 1D. All ptxunderwentthree Te-99m-MIBISPECT ltudie~performed15 day~apart: I. after ~ubmaximalEx (with 85% age-predicted heart rate achieved); 2. after Dip 0.56 mg/kg, injeetad iv, in cormeetionwithminimalEx; 3. at re~t In group L agreement in defect ~ize~, typeG,and localization between Ex and Dip Spectwa~observedin 23 pt~;in one pt defect in Ex wa~largerthan in Dip. In group 11, total agreementwa~obtained. In group 111, maximalhear~rate rangedfrom 137 to 166 bpmduringEx~Threept~had maximal heart rate > 160 bpm. One of them had greater defeel in Ex SPECT, but localizationwai the ~amein both~tudie*. Agjeementwa~observedin 34 pt~. In group 1g,, perfugiondefeet~were the ~ame in Dip and Ex SPECT in 29 of 31 pt~. In two ~ tramientchangetin infarctedzone~were largerin DipthanEx SPECT. In conclusion: 1. Dip Tc-99m-M1BISPECT did not bringmore information6about parfu~iondefect*than ExTc-99m-M/BISPECT in invegtigated~ituation~. 2. In pNwithoccludedcoronaryarterythe agreementbetweenthe two method~i~not dependenton the pre~eneeof collateral circulation. 3. Ex and Dip Tc-99m-IvIIBISPECT may be n~ed exchangeablyin pt~ with LBBB when85% age predictedheart rate i~below 160 bpm,

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T H A L L I U M 203 SC3NTIGRAPHY 1N C O M P L E T E L E F T BUNDLE BRANCH BLOCK Z. Stamenkovic, S. Grujic, D. Kovacevic, M. Maletin, D. Rebic, M. Cvetkovic. Institute of Cardiovascular Diseases, Sremska Kamenica - Novi Sad, Yugoslavia

LUNG/HEART RATIO IN 'mTI-SPECT WITH EXERCISE AND PHARMACOLOGICAL STRESS. A. Cabrera A. Maceira, M.J. Garcia Vetloso, I. Coma Canella*, A. Villas, V. A1badalejo*, J.A. Richter. Departaments of Nuclear Medicine and Cardiology*. University Hospital o f Navarra. Spain.

Myocardial scintigraphy at rest and during exercise was performed after the administration of thallium 201 in 65 patients with the complete left bundle branch block and anginal discomforts particularly during exercise, aged 37 65 and the mean values of 54 _+13. The finding of coronary angiography was normal in all patients, out o f 65 patients, 18 patients had left ventricular hypertrophy and 5 patients had dilatation o f the left ventricle. Insignificant I V A stenosis was found in 8 patients. Reversible perfusional defect was noticed in 36 patients and irreversible defect in 29 patients, i.e. hypofixation of TI 201 was notified 4 hours after TI 201 redistribution in the anteroseptal part of myocardium. This "functional ischemia" is in all probability the sequel o f the prolonged compression of the septal arteries because of asynchronous contraction due to the let~ bundle branch block,

The objective of this study was to examine the thallium biokineties and to compare lung/heart ratio during exercise (EX), dobutamine (DB), adenosine triphosphate (ATP) and dipyridamole (DP) stress testing. Four groups of 30 healthy volunteers each underwent 2°tTl SPECT during exercise (EX), DB infusion (40 pg/Kg/min), ATP infusion (160 pg/Kg/min for 6 min) and DP infusion (140 p.g/Kg/min for 4 rain). A ROI over the right lung and other ROI over the myocardium with maxhaaal activity were drama in order to calculate activity both in heart (AH) and lun~ (AL) as well as the lun~heart ratio (LHR). EX DB ATP DP A.H. 125.8+_23.1 175.7_+29.8 165.8_+29.9 184.9_+21 A.L. 37.8+7.6 46.4_+8.9 52.3-+7.6 49.5-+5.12 LHR 0.29_-2-0.3 0.26-+0.3 0.32-+0.1 0.26+0.3 2°lTl A l l with pharmacologic stress was higher than with exercise (p<0.00l). AL with ATP and DP were higher than with EX and DB (p<0.001). However, no significant differences among these groups were found in LHR. Conclusion: Although averagc miocardial and lung uptake with the four types o f stress was different, fine LHR in these groups was similar,

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M O N D A Y

A M A P R I L 7

Abstracts Monday morning, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

8.6

8.8

EFFECT OF GENDER BASED NORMAL DATABASES ON THE DIAGNOSTIC ACCURACY OF QUANTITATIVE SPECT THALLIUM IMAGING Christopher L. Hansen, David Travis Temple University Hospital, Philadelphia, PA

ADENOSINEAND ARBUTAMINECOMPAREDDURING MYOCARDIAL PERFUSIONIMAGING C Anagnostopoulos, DJ Pennell, J Francis, K Serup-Hansen, G Davies, SR Underwood, Royal Brompton Hospital, London, UK.

The utilization of gender based databases has become routine despite the fact that their ability to improve diagnostic accuracy has not been rigorously proven. We identified 475 patients who had either less than 5% pretest probability of coronary artery disease (nls) or who underwent cardiac catheterization within 60 days of stress testing (pts) without an intervening event or procedure and who had no documented history of infarction, pathologic Q waves, LBBB, previous CABG or nonischemic cardiomyopathy. Twenty M and 20 W were removed from the nls and used to create gender based (GB) and non-gender based (NGB) normal limits. The remaining 435 patient images were quantitated using GB, NGB and a constant threshold of 60% of maximal activity (CT). The area under the receiver operating characteristic curve was calculated for each method of quantitation then compm~ed. The diagnostic accuracy was not significantly different when comparing GB and NGB (Area GB= 0.91 vs NGB= 0.90, p = 0.35). However, both the GB and NGB had greater accuracy when compm-ed to CT (Area CT = 0.85, both p < 0.0001). We conclude that both GB and NGB improve diagnostic accuracy when compared to CT but that GB normal limits provide no significant improvement in diagnostic accuracy over NGB.

We have compared adenosine and arbutamine "stress" during thallium-201 myocardial peffusion imaging (MPI) in order to assess the comparative value of the newer agent. We studied 23 consecutive patients referred for MPI, and each patient had two studies (18 male, mean age 62 years, 5 with previous myocardial infarction). Uptake scores were assigned to each of 9 segments, and the extent and sevedty of defects were measured using a polar plot. Haemodynamic changes were greater with arbutamine (double product increase 76% vs 51%, p=0.003). Symptoms were experienced by 21 patients with arbutamine and 16 with adenosine (p>0.05). There was no significant difference in the number of patients who were classified as normal or abnormal by the two agents. Agreement for classification of defects as reversible fixed or mixed was good (]<=0.71). Segmental agreement for stress scores was also good (1<=0.77). Mean size of stress defect was larger with adenosine (83_+52pixels vs 65_+48pixels, p<0.05), but severity and reversibility were similar (p>0.05}. Thus, there is good agreement between the techniques and the observed differences are not clinically significant.

8.7

8.9

OPTIMAL VIAL SIZES FOR ADENOSCAN ®. JC Hung, DW Mahoney, DL Johnston, RJ Gibbons. Mayo Clinic, Rochester, MN, USA.

IMPROVEMENT OF DIAGNOSTIC SPECIFICITY BY CHANGING OF PATIENT POSITION FROM SUPINE TO PRONE POSITION IN MYOCARDIAL SPECT PATIENTS WITH CORONARY HEART DISEASE (CHD) P.Reuland, M.Irmer, University of T0bingen, Germany.

Adenoscan~ (Fujisawa USA, Inc., Deerfield, IL, USA) is packaged in a 30-ml vial for single use only since it contains no preservative. This restricted usage generates considerable waste and unnecessary per patient cost. The purpose of this study was to investigate a 2-vial system that would provide limited amounts of waste while maintaining practicalities to satisfy different patient populations. The least waste for each potential combination of two vials was calculated by assuming that patient weights follow a normal distribution. The least expected waste for a variety of possible patient weight distributions is summarized as follows: Body Weight Least Calculated Waste for Distribution (kg) Different Vial Sizes (ml) 30 5+15 6+15 9+15 40 + 25 11.0 2.5 1.4" 2.2 65 + 25 10.6 2.5 1.5" 2.0 90 -+25 13.9 2.6 1.8 1.7* 115+25 18.0 2.6 2.2 1.6" *The least calculated waste from the optimal 2-vial combination. The 6+15 ml combination has the least waste for lighter populations and the 9+ 15 ml system has the least waste for heavier populations. Additionally, the calculated wastes at Mayo Clinic (83 ± 19 kg, n = 4,207) were 10.5 _+9.3 ml (30 ml), 2.5 + 1.5 ml (5+15 ml), 1.6 + 1.0 ml (6+15 ml), and 1.8 _+1.2 ml (9+15 ml). In general, the 5+15 ml vial combination performs far better than the single 30-ml vial and is close to the optimal vial combination. The combination of 5-ml and 15-ml vials also allows a standard and practical commercial packaging of Adenoscan®.

While the diagnostic sensitivity of myocardial scintigraphy is high, especially artifactual tracer defects in the inferior wall reduce the i specificity for diagnosing CHD. We have studied the influence of! patient positioning in myocardial SPECT on the diagnosis of CHD in 34 female and 45 male patients. By using 99mTcTetrofosmin as myocardial tracer, scintigraphy in prone and supine position could be performed within 30 minutes, thus allowing for a direct comparison of the findings. All patients underwent coronarangiography within 4 weeks. 10/39 tracer defects in the inferior wall found in the examination with the patient in supine position normalized or decreased in the examination with the patient in prone position. 4•30 defects in the anterior wall were reduced or normalized in the examination with the patient in the prone position. No changes were seen in 9 rasp. 8 defects of the lateral resp. septal wall. While the sensitivity was not changed as confirmed by coronarangiography specificity was increased for men from from 56 to 67% (for the inferior wall) and for women from 59 to 63% (for the anterior wall). In myocardial SPECT specificity is significantly improved by. changing the patient position from supine position to prone position. The diagnostic sensitivity for CHD is not changed by the changed patient position.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Monday morning, April 7, 1997

8.10 IS 99M-TC-TETRAFOSMIN SPECT USEFULL CORONARY ANGIOGRAPHY IN CASI~ OF A NON-DIAGNOSTIC STRESS EKG?

8.12 BEFORE

F.A.van der Weel, M.J.Nooitgedacht-de Haas, W. Kolsters, M.LM. Cramer, Ziekenhuis Eemland Amersfoort, the Netherlands. Myocardial spect (MYSPECT) was performed in 390 patients suffering from chest pains. Cardiac stress was created by symptom-limited bicycle ergometry or intravenous dipyridamole infusion (0,56 mg/kg in 4 minutes). A two day protocol with 750 MBq 99mTcTetrafosmin for the stress and rest studies was used. A subgroup of 153 patients,102 man, (age 44-69) and 51 women, (age 46-75) who underwent Coronary Angiography because of a positive Myspect result was studied. The stress EKG was non diagnostic in 67% of these 153 cases and for this reason alone they would not be candidates for a coronary angiography. Followup data from this group showed that 20% underwent bypass surgery and another 20% underwent a PTCA. Without the Myspect data a considerable delay in treatment was the least to be expected. We conclude that early Myspect with 99mTc Tetrafosmin is usefull in the workup of patients with a non diagnostic stress EKG and chest pain. This study shows that a considerable number of patients would otherwise be treated in a suboptimal way.

Tc-99m SESTA-MIBI SPECT IMAGING IN ANGINA PATIENTS WITH ECHOCARDIOGRAPHIC LEFT VENTRICULAR HYPERTROPHY (LVH) S C Chae, H S Park, Y K Cho, J Lee, J E Jun, W H Park, Kyungpook National University, Taegu, Korea Tc-99m sesta-MIBI myocardial scan was performed with either exercise (n= 42) or adenosine (n= 41) stress in 83 anginal patients with normal ECG. Fifty four patients had significant coronary artery disease ( > 50%) in coronary angiogram. Overall sensitivity and specificity of the SPECT imaging were 87%, 76%, respectively. The patients were divided into 2 groups by the absence (group 1, n= 51) or presence (group 2, n= 32) of echocardiographic LVH; LVH was diagnosed if left ventricular mass in M-mode echocardiogram exceeds 131 g/m 2 in men, 100 g/m 2 in women. Sensitivity of the SPECT imaging w a s 86 % in group 1 and 88 % in group 2 (p= NS), respectively. Specificity of the SPECT imaging w a s 86 % in group 1 and 67 % in group 2 (p= NS), respectively. Echocardiographic LVH does not appear to affect the diagnostic accuracy of sestaMIBI myocardial SPECT imaging in the anginal patients without evidence of ECG LVH.

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8.13

AdenosineScintigraphyin PatientswithChronicObstructive PulmonaryDisease:RoutinePretreatmentwitha Bronehodilator DonaldL. Johnston,DavidO. Hedge, RobertB. Glynn, Raymond J. Gibbons. Mayo Clinic, Rochester,MN, USA

ADENOSINE STRESS TEST AND 99'~-Te-TETROFOSMIN SPECT IMAGING FOR THE DIAGNOSIS OF C.A.D. L Lumbreras, D Becetwa, R Nieto, B Fem6ndez, .4 Nevado, 0 Padilla andJJM Sampere. Hospital Clinico Universitario. Granada (SPAL\:).

To determineif pretreatmentwithan inhaledbronchodilator(BD) wouldallowadenosineto be usedsafelyin pts withCOPD during peffusionscintigraphy,94 pts were studiedwithpulmonaryfunction testingbefore,duringand 15 rainafter infusionof a graduateddose of adenosineto a maximumdoseof 140 ug/kg/min(monitoredpts). Pts witha forcedexpiratoryvolumein 1 sec (FEV1) of <30% (predictedfor age), FEV1 30-40°/° + BD response>15% or FEV1 >40% + BD response>30% receiveddobutamine.MildCOPD was presentin 39 pts (FEV1- 2.10+0.63 Umin); moderate-severe COPD was presentin 55 (FEVl- 1~9+0.38 L/rnin).Upon completionof thisportionof the study_ptswithsuspectedor knownCOPD receivednebulizedAlbuterol(2.5 rag)followedby adenosinewithoutsimultaneousPFT (n=80 - unmonitoredpt). The changesin FEV1 withadenosinewere not differentfor mildvs severeCOPD. One monitoredpt had adenosinedecreaseddue to a decreasein FEV1 >20% butwas asymptomatic.No unmonitoredpt had adenosinedecreaseddueto dyspnea. FEVl (mean - L/rain) Monitored rest p-BD 140 ug/kg/min 15 min post pts (n=94) 1.69 1.83 1.78 1.78 p<0.001 In summary,adenosineis now routinelygivento selectedpts with moderateand severeCOPD usinga nebulizedBD pretreatment withoutthe needfor simultaneouspulmonaryfunctionmonitoring.

OBJECTIVEs: The purpose was to evaluate (1) the usefiflness of adenosine infusion coupled with 9~"Tc-tetrofosminscintigrap~' in the assessment of CAD and (2) compare ~ o protocols of s~ess with adenosine (infusion alone vs combining with exercise) to determine the presence of side effects and inaaging euali~', METHODS: n= 112 consecutivepatients were randomized to two study groups: (A) 6 rain of adenosine infusion alo-ae (140 ;.~gr/kg/minx6 man) and tl~) 6 nfin of combined exercise with adenosin, Protocol stress/rest. RESULTS: DA n=30

Sensib. Espec. VPP VPN E.D

[

CX Gr-A

I Gr-B

CD

Gr-A

Gr-B

Gr-A

0.88

1.00

0.75

0.83

1.00

Gr-B 0.75

0.86 0.88

0.80 0.91

1.00 1.00

1.00 1.00

1.00 1.00

1.00 1.00

0.86

1.00

0.92

0.90

1.00

0.78

O87

093

0 93

0.93

l ,I)O

('1.87

Additional exercise caused signilieantly increases in heart rate (16,78 vs 0.5; p<0.0001). Systolic and diastolic BP also increased compared with the decrease in BPa seen with adenosine alone (BPs:9. lmmlIg; BPd:5.95). We report a reducing in noncardiac side effects combining exercise with adenosine infusion.

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Abstracts Monday morning, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

8.14

8.16

MYOCARDIAL FATTY ACID METABOLISM IMPROVES WITH LOW-LEVEL PHYSICAL TRAINING IN PATIENTS WITH PREVIOUS MYOCARDIAL INFARCTION Ryuichi Ajisaka, Shigeyuki Watanabe, Noriyuki Takeyasu, Haruna Ohnuki,Tohru Takeda, Yasuro Sugishita. University of Tsukuba, Tsukuba, Japan

WHICH RELATIONSHIP A M O N G E X E R C I S E TEST (EET) RESULTS, THE EXTENT OF REVERSIBILITY ON MIBI/SPECT AND PROGNOSIS ? G. Marcucci*, N.R.Petix, M. Sih, estri*, A. Arena*, V. Mazzoni, A. Mennuti*, A. Bini. * Nuclear Medicine Department, Prato and Cardiology Department, Empoli (Fi).

Physical training improves exercise tolerance, but its effect on myocardial metabolism has not been established. Fourteen patients with previous myocardial infarction wereprospectively randomized either to a training group (n=7) participating in low-level physical training or to a physically inactive control group (n=7). At baseline and after i0 months, patients underwent symptom-limited bicycle exercise testing, 123IBMIPP scintigraphy and 99m-labeled tetrofosmin ( Tf) scintigraphy. BMIPP and Tf uptakes were assessed by a semiquantitative scoring method. Results: BMIPP score increased (20.9~6.0-~22.3~ 6.0, P<0.05) in the training group,but didnot change in the control group. Tf score did not change in the training group. Ventilatory threshold (ml/kg/min) increased (9.0±0.9-~11,1~ 3.6, P<0.05) in the patients who had an increase inBMIPP score (>2) , while it did not change ( 9.6~0.5-~8.3±0.9) in the patients with no increase in BMIPP score(<1). Thus,long-term, lowlevel physical training may improve myocardial fatty acid metabolism without an improvement in myocardial perfusion.

In order to evaluate the prognostic power of EET results and the extent of reversibility on MIBI scan,we followed 306 pts (230 m,mean age 58,166 with prior MI) for 19_+11 mos after EET MIBI/SPECT, Considering 5 segments for pt, average % of segments with reversible (%R) and irreversible (%IR) defects, according to EET results and hard cardiac events (HCE) (4 deaths and 20 MI), were : Pts %R HCE(pts) %IR HCE(pts) Negative max EET 62 8.06 3 10 I Isolated ST depression 80 21.5" 6 6.25 1 Ang+ST depression 60 21.33" 5 13.33 0 Angina 35 20.57* 2 11.43 1 Early recovery < 6' 49 16.73 0 9.39 I Late recovery >_6' 91 23.96* 1I 8.77 0 Not diagnostic 69 I 1.01 3 16.8" 2 RPPmax _ 20.(~')0 104 20.38* 10 10.45 2 RPPmax >20.fX)O 202 14.13 8 13.14 3 EET< I00W 116 21.3" 10 10.57 I EET >__100W 190 12.9 8 I 1.91 5 p ~ 0.05 vs other data of same column In conclusion cumulative HCE-free survival rate obtained by the combination EET and MIBI results showed that:l) a negative maximal EEl" with normal scan had a favorable long term prognosis; 2) the pts with late recovery and reversible defect were at high risk of HCE;3) EET- derived parameters were associated with a more extensive stress-induced R% and poor prognosis.

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8.17

CORRELATES OF STRESS-INDUCED ~°lTI REVERSIBILITY VARY ACCORDING TO ST SEGMENT RESPONSE G.Y. Oudit, R.J. Burns, University of Toronto, Toronto, Canada.

DIPYRIDAMOLE THALLIUM-201 STUDIES MAY BE ABNORMAL IN LV HYPERTROPHY BUT CORRELATION WITH DIRECT MEASURES OF CORONARY FLOW RESERVE IS POOR Smith V-E, McCandless BK, Karimeddini MK, Breisblatt WM, Houghton JL, Strogatz DS Albany Medical College, Albany NY

We compared 71 consecutive 2°1TISPECT cases (cohort=7075, 1%) with stress-induced ST segment elevation (STE) to matched (for age, sex, stress protocol, test indication) 'ischemic' ST depression (STD) cases. 2°~TI SPECT was interpreted by visual consensus and quantitatively (Cedars-Sinai). 2°1TIreversibility (TR) was seen in 46 STE vs 61 STD patients (p=0.003), but overall extent, degree, and distribution of TR were similar. We then compared TR vs no TR cases in STE and STD groups: STE:TR - - n o T R - ~ STD:TR - noTR-12 reels 8A-+1.7 7.3_+2.2 NS 7.5±1.8 8.9±1.2 .005 # leads 2.7+1.9 2.4+1,5 NS 4.9_+1,7 3.8+1.0 .014 ~.AST +10±7 +10-+6 NS -8+4 -6_+2 .024 -_,AST/HR +.09-+.04 +.08_+,04 NS -.06+.04 ..04-+.01 .001 A'£QRSImeI 1,1_+3.6 0.5_+3.0 NS 1.2_+0.9 0.7-+0.2 .001 LV dilation 19146(.35) 7/25(.28) NS 15/61(.25) 0/10(0) .023 # leads = no. leads with ST change; ).;AST = sum of ST changes(ram); ZAST/HR = ZAST + maximum heart rate; AZQRS/rnet= increase in summed QRS amplitude (ram) +mets; LV dilation = transient on a)Tl stress images

CONCLUSION: STD and TR are associated with known correlates of stress-induced ischemia but STE and TR are not. This suggests different mechanisms of STE ischemia (e.g, high segmental wall stress, focal/pert-infarctischemia) and/or of TR (e.g. defect expansion/contraction ratherthan reversibilityperse).

To assess the effect of LVH on myocardial thallium distribution during stress, we evaluated 91 men and women with and without hypertensive LVH who were free of >30% epicardial coronary luminal narrowing. Endothelium dependent (ED) and independent (EI) augmentation of basal coronary flow (CFA) during intracoronary adenosine and acetylcholine was determined. SPECT thallium-201 images were obtained after dipyridamole-low level stress. Semiqumatitative image analysis by 4 observers yielded 25/91 abnormal tests. LV m a s s (but not geometry) and white race (both p<.01) predicted abnormal stress images even after adjustment for BMI, hypertension and gender. Age and gender were weakly related to thallium test result. Of note, the presence of any stress abnormality did n o t correlate with either EDCFA or EICFA. Thus patients with LVH may have abnormal stress thallium images, but the mechanism remains unclear.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Monday morning, April 7, 1997

8.18

8.20

MYOCARDIAL PERFUSION IN PATIENTS W I T H DDD PACING A. Le Helloco, A. Devillers, J. L. Alberini, M. Bedossa, P. Bourguet, C. Almange. Department of Cardiology and Nuclear Medecine, University Hospital, Rennes, France

IS D I P Y R I D A M O L E - t N D U C E D S T - S E G M E N T DEPRESSION SPECIFIC E N O U G H [N DETECTING C O R O N A R Y A R T E R Y DISEASE ? DJ Wang, CY Cheng, SP Yang, WL Chen, DA Wu. TriService General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC.

Exercise myocardial tomography could localize ischemia in patients (pts) with DDD pacing, but myocardial perfusion abnormalities are possible, 48 10ts implanted with DDD pacemaker for high degree AV block (38 pts) and sick sinus syndrome ( | 0 pts) were divided in group 1 (24 pts) without significative coronary stenosis, in group 2 (24 pts) with 14 one vessel disease (v.d.), 5 two v.d. and 5 three v.d.. Angina was present in 36 pts, atypic/q chest pain in 12 pts and myocardial infarction in 13 pts. All pts underwent exercise test (E.T.)coupled with dipyridamole Thallium tomography (SPECT) and coronary angiogram. Exercise test is insufficient for diagnosis of coronary artery disease (C.A.D.) : 10 pts with angina in group 2 vs 2 pts in group 1 (p < 0,01).Sensitivity (SE) of SPECT is excellent (95,8 %), but apical defect is frequent in group 1 (specificity SP = 54,2 %). SE SP LA.D. 66,6 % 59,4 % LC.X. 62,5 % 93,7 % R.C.A. 81,8 % 69,2 % In pts with DDD pacemaker, dipyridamole SPECT is useful for diagnosis of C.A.D..

Dipyridamole-induced ST-segment depression (STD) is not unusual in intravenous dipyridamole thallium-201 myocardial perfusion imaging (IVDTL). To testify the diagnostic accuracy IDA) of the STD in detecting coronary artery disease (CAD), 126 subjects underwent IVDTL were included in this study. Of the 126 cases, 28 had angiographically proved normal coronary arteries and 98 had CAD with exclusion of myocardial infarct. In comparison with the DA o f reversible perfusion defects (PD), the DA of STD, chest 3ain and noncardiac SIS (symptoms and signs) in detectIn~l CAD were: SN, sensitivity; SP: specificit N (n=28) CAD (n=98) SN ; SP DA positive negative positive I negative! (%) i (%) (%) !STD:=:' ::'l :1 2 2 : 7 6 : 3 9 .'hest pain 6 22 2,5 73 26 78 37 ~loncardiacSIS 12 16 30 68 31 57 36 ,Reversible PD 1 5 I 23 I 87 I t l 1891821 87 It is therefore concluded that 1) the cardiac (STD and chest pain) and noncardiac SIS are not accurate indicators in CAD detection, and 2) the ST-depression during dipyridamole infusion is a very specific, but not sensitive, indicator in detecting CAD.

8.19

8.21

INFLUENCE OF PREVIOUS MYOCARDIAL INFARCTION ON THE DIAGNOSTIC VALUE OF Tc99m-TETROFOSMtN SPECT Freire JM, Fajares M, Nieto R*, Becerra D*, Otero E, Lumbreras L*, Sancho M, MSempere J*,University Hospital Cadiz*Granada Spain.

USEFULNESS OF REST IODINE-123- 13-METYL [ODOPHENYL-PENTADECANOICACID (BMIPP) IMAGES TO DIAGNOSE UNSTABLE ANGINA PECTORIS - ESTIMATION USING DELAYED IMAGE-. T.Hatori, T.Toyama, H.Hosizaki, T.Iizuka, N.Kanazawa, H.Wakamatu, H.Arisawa, T.Inoue, K,Endou, T.Suzuki, O. Uchida, R.Nagai. The Society of Gunma Myocardial Metabolism,Macbasi,Japan.

The aim of this study was to analyze if the previous myocardial infarction (Mt) modifie the sensitivity (SN) and specificity (SP) of 99mTc-tetrofoemin myocardia~imaging in the detection of significant coronary stenosis. SPECT 99mTc Tetrofosmin one-day stress-rest imaging protocol were performed in 115 patients (89M, 26F) who had undergone diagnostic coronary angiography. Sixty-three patients (pt) showing pdor myocardial infarction, There were 20 pt with no coronary axteryd~sease(CAD), 43 pt ~4th one-vessel (~7G% diameter narrowing as significant stenosis), 29 pt with two-vessels and 23 pt with three-vessels disease. Myocardial SPECT data were evaluated visually by two independent observer using a five segment five score system (0: normal to 4: absent uptake). The Sensitivity for CAD detection were 100% in patients with and whitout prior MI. We observed diferences (p=0.03) in the detection of significant stenosis between patients with MJ (8N:90%) and patients without MI (SN.80%). Concerning localization of individual coronary artery (n=345), the following values were obtaining: SENSITIVITY ALL WITH MI WHITOUT M[ LAD 90% 93% (38141) 86% (25129) n.s. LCX 73% 82% (23/28) 54% (7/13) n.s. RCA 90% 93% (38141) 62% (14117) n.s. SPECIFICITY LAD 80% 77% (17/22) 83% (19123) n.s. LCX 95% 97% (34135) 92% (36139) n.s RCA 89% 86% (19/22) 91% (32t35) n.s. Our result suggest that the diagnostic value of Tc99m-Tetrofosmin SPECT is similar both Jn patients with and without MI.

We estimated delayed BMIPP scintigraphy to diagnose unstable angina pectoris (UAP). Sixteen patients with UAP underwent the rest early and delayed BMIPP imaging and TI imaging on the other day. In 21 segments of the SPECT, regional tracer uptake was scored using 4-grade uptake score, and summed up to defect score (RDS). Coronary arteriography was done in "allpatients and the stenosis above 75% was thought to be significant. The diagnostic rate was 48%(10/21) on the rest TI imaging, 76% (16/21) on the early image and 90% (19/21) on the delayed image of BMIPP imaging, whose RDS was 2.0 ----2.7, 5.1 +4.7* and 6.3--5.7% respectively ( * ; p<0.01 vs T1 ).We conclude that the rest delayed BMIPP image is useful to diagnose unstable angina pectofis.

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Abstracts Monday morning, April 7, 1997

8.22

M O N D A Y

A M A P R I L 7

HIGHER DIAGNOSTIC ACCURACY OF THALLIUM VERSUS ECHODIPYRIDAMOLE IN CORONARY ARTERY DISEASE P:Bonomo, L.Mossa, B.lallu, W.8oi, S.Piras, L.Tocco, M.Boero, G.Pili, G.Chiriu, E.Rosas, B.Passiu, MPili, S.Ocello, A Cualbu, M.Celeghini,M.Raffo. UTIC Osp. SS.Trinit~-CagliariItaly AIM of the study was to compare the efficacy of thallium planar miocardial stress scintigraphy(TH) with that of dipyridamole-echo (DET) and exercise testing (ET) in the diagnosis of coronaropathy assessed i~yangiographyas gold standard. STUDY included53 pazienta (45 males) aged 36 to 79 years, mean 56.6, consecutivelyadmitted to our coronarycare unit during the last 26 mo.,with ischaemic eardiopathy.Patientswith EF< 30%, persistent ischeemic, in-~tability, stable ventricular arrhytmias, valvular heart disease, pacemaker,asmatic disease, poorechocardiographywindow were escluded; (being out tests contraindicated)also escluded were those patients that had to undergo urgent coronarography and/or revascularization.Of the patients studied, 18 had acute infarction, 15 anginawith hiatob' of miocardial infarction,20angina.Allpatients had FE>30%Each patients underwentET, DET, TH tests in the sequence at 3-10 day interval, followed by eorona~ artedograpby 1 to 44 (mean 28) days after the last test.Each patientsmaintainedthe same medication or had beenwashed out duringthe experimentalperiod. RESULT. Angiography: 5 patients had no clitical stenoais; 21,11,12 patients had significant stenosis in 1,2,3 vessels respectively; four patients in common choronary trunk. TH gave 44 positive and 2 false positive, 6 negative and 3 false negative,3 doubtful (coron. positive) responses. DET 38 positive(1 false),12 negative (3 f), 3 doubtful (2 coron positive) ET 29 positive(3 0,12 negative (.10 t),6 doubtful (2 coron positive).Thusthe diagnosticsensitivityof TH,DET and ET was 93, 80, 72 % respectively.Diagnosticspecificitywas 60, 85, 40 %. Diagnosticaccuracywas 85, 75, 59 %. IN CONCLUSION inspite of limitation due to the presence pre test high coronarepathy probability (91% lesioned and 51% multivasal) and high necrosis incidence(62%), differenttests have shown good reliability, TH being the most accurate.

Journal of Nuclear Cardiology January/February 1997, Part 2

8.24 THE EFFECT OF ALACEPRIL(ACEI ) FOR THE MY0CARD I AL SYMPATHET I C NERVE I N HEART FA 1LURE PAT I ENTS WI TH HYPERTENSI ON EST I MATED FROM I - 123 M I BG MYOCARDI AL SPECT I MAC I NG M 0kada, Y. Tanahash i, Y. Saka, Nagoya Eki sauka i Hospi ta I, ~goya, Japan The purpose o f the p r e s e n t s t u d y was to evaluate the e f f e c t s of a l a c e p r i l f o r the sym.pathetic nerve in heart fai lure patients w i t h hypertension using MIBG myocardial SPECT images. The study p o p u l a t i o n consisted of 15 p a t i e n t s (9 with oral alacepri I). ] h e systolic a-d diastol ic blood pressure decreased s i g n i f i c a n t l y a f t e r alacepri I(p<([ 05). ]he LV d i a s t o l i c and s y s t o l i c dianeter showed no s i g n i f i c a n t changes in LEG f i n d i n g s a f t e r alacepri I. The uptake rate of MIBG increased significantly after alacepri 1(7(~ 5 - 74. 5~, p<0. 05), but uqchanged in non-alacepri I. The washout rate of MID6 decreased s i g n i f i c a n t l y a f t e r alacepri 1(47.2~3& 7~ p<0.05), but in n0n-alacepri I. It was concluded that alacepril inproved the f u n c t i o n of myocardial s y ~ a t h e t i c nerve system in heart fai lure patient&

8.23

8.25

MYOCARDIAL STRESS TI~STS IN THE DETECTION OF ASY'MPTOMATIC DIABETIC PATIENTS CORONARY ARTERY DISEASE. S. Rndoni, Y. Cottin, S. Pr6vot, C. Damatte, G. Vaillant, B. Verges, J.M.Brun, F. Brunette. Service d'endocrinologie et maladies mStabeliques, CHU Bocage, Centre Georges Francois Leelerc, Dijon, France. Corunary artery disease (CAD) is a major cause of morbidity and mortality in diabetic patients. Thallium SPECT after exercise stress testing (T1) improves the non invasive approach sensitivity and specificity. Diabetic patients are often unable to exercise optimally because of obesity, peripheral arteriopathy and/or associated neuropathy. They are candidates for dipyridamole stress testing (0.56 mg/kg) (T2). A standardized low-lewel bicycle exercise (men 40 W/4 minutes - women 30 W/4 minutes) following dipyridamole infusion (T3) is an altenmlive which increases myocardial request and improves file contrast between myocardimn and adjacent area. The aim of this work is to compare file frequency of use of the 3 stresses in 197 asymptomatic diabetics (D/A) (112 men, 85 women) versus a population of 941 non diabetic patieuts comparable in age (POP) (604 men, 337 women reffered for the detection of CAD. AGE (years) m -+SD T1 "1"2 T3 DIA (%,) 61.5 + 9.4 27.4 48.7 23.9 POP (%) 60.4 + I 1.4 37.7 37.6 24.7 p 1,IS <0.0l <0.01 NS The results show that the maximal exercice test (TI) is more frequently used iu non diabetics patients. Dipyridamole infusion (T2) remains the preferred procedure for diabetics. The combined test (T3) is used in 23,9 % of cases at least in the two groups. Considering the combined tes~ synergic effect on myocardial ischemia induction, this test should be suggested rather than dipyridamole infusion alone in asymptomatic diabetic patients.

ASSESSMENT OF THE OCCURRENCE OF SYMPATHETIC CARDIAC RE-INNERVATION AFTER HEART TRANSPLANTATION. M.Estorch, I.Carri6, X.Ruira, A.Flotats, LI.BernL C.Mari, A.Catafau, M.Ballester. Hospital de Sant Pan. Barcelona. Spain. We studied 26 transplant patients by rest-exercise ventriculography and myocardial 1231-MIBG scintigraphy. Nine patients were studied between 6 months and 2 years (a), and 17 were studied between 2 and 11 years after transplantation (b). LVEF and peak filling rate (pfr) were calculated, and myocardial uptake of MIBG was expressed as heart to mediastinum ratio (HMR). There were no significant differences between LVEF and pfr at rest and during exercise in the two groups. Pfr at exercise was higher in group b ( 2 . 7 0 + . 8 3 vs 2 . 1 6 + . 4 7 , p = 0 . 0 2 ) . In group a, 4 patients (44%) had mild antero-lateral MIBG uptake ( H M R = l . 3 4 + . I 6 ) , and 5 (56%) had absent M l B G u p t a k e ( H M R = 1.14+__.21). In group b, all patients had antero-lateral MIBG uptake ( H M R = 1.62__+.23), the intensity of uptake was mild in 11 (65 %) (HM R = I. 43 _ . 17), and moderate in 6 (35 % ) ( H M R = 1 . 7 0 + . 2 3 , p = N S ) . HMR in group b was higher than in group a ( 1 . 6 2 + . 2 3 vs 1.34+.16, p = 0 . 0 5 ) . In conclusion, sympathetic re-innervation occurs after transplantation in the antero-lateral wall. An incre&se in exercise pfr is then observed. Myocardial MIBG uptake increases with time. Two years after transplantation only 44% of patients have evidence of cardiac re-innervation.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Monday morning, April 7, 1997

8.26

8.28

CARDIAC SYMPATHETIC INNERVATION IS REDUCED FOLLOWING CARDIAC SURGERY WITH MYOCARDIAL COOLING. M.G. KoutelouI, G. Economopoulos2, S. Papaioanous, A. Karoussoul, A. KonzoumiI, S. Karabotsou,D.V Cokkinos3. INuclear MedicineDepartment, 2Cardiac Surgery Department,31st Cardiolo~' Department, 0nassis Cardiac Surgery Center, Athens, Greece.

MYOCARDIAL 123-I-MIBG WASH-OUT RATE IN ACUTE HYPOTHYROIDISM R. Sciuto, A. Tofani, A. Fcrraironi, S. Rea, C.L. Maini "Regina Elena" Cancer Institute, Rome, Italy

Iodine-t23 metaiodobenzylguanidine(MIBG) imaging has been used to demonstrate regional sympathetic innervation of myocardial tissue in various clinical and experimental settings. We used MIBG to assess innervation in 10 patients (mean 63-+8 years) who undenvent cardiac surgery employingmoderate h~othermia (32°C) cardiopulmonaryby-pass with cold blood cardioplegia and myocardial temperature ranging from 10 °C-18 °C using cold saline irrigation(4 °C). Pts were studied 1 day prior and I week following surgeD'. MIBG uptake was quantified by heart/lung ratio on planar images 4-5 hours post injection.Regional uptake was estimatedin 20 segments of the tomographic images by using a 4 point scoring system(0=normal and 4=no uptake). Heart/lung ratio was decreased significantly following surgeD' (1.18+0.32 to 0.76_+0, p=0.004). The total MIBG uptake score was increased(3.1_+3.2 vs 6.0_+3.7respectivelyfor preand post-surgery, p=0.001). No correlation was found between the changes in the heart/lung ratio and time during which the heart was exposed to hypothermicby-pass. In cooclusion,regional neuronal innervafionexpressed by MIBG uptake is reduced early after cardiac surgey. The precise mechanism of this finding needs to by elucidated,however it is possiblethat cooling of the myocardiumplays an importantrole.

S 1l

Ten patiens with differentiated thyroid carcinoma in acute h q)othyroidism (A) and on hormonal replacement wit!z %4 150 ~/dic and T,3 20 g/die (B) underwent scintigraphic imaging at 20 min. and 4 hrs. after injection of 111 MBq of ultra-high specific activity 123-I-MIBG (Sorin, Saluggia, Italy). None of the paticns had cardiac disease or was taking medications interfering with cardiac or automic nervous system function. Myoca;dial washout rate (lVlWR, %), serum nor-ephinephrine (NE, mnol/L), TSH (FU/ml) and FT4 (pg/ml), heart late are reported as mean and s.d. together with prevalence ofaspecifie ST/T abnormalities.

.~t7±

3"7

i ~.25+_0,19

62J~6

"/10

The following conclusions can be dragon (1) iatrogenic acute hyl0othyroidism is associated with alterations of cardiac adrenergic state as shoma by an increased MWR; (2) replacement thyroid homaone therapy rapidly reverses MWR to normal.

8.27

8.29

IMMEDIATE AND LONG TERM EFFECTS OF CARDIAC SURGERY ON MYOCARDIAL SYMPATHETIC INNERVATION M. Koutelou, G. Economopoulos,S. Papaioarmou,D.V. Cokkinos, Onassis Cardiac Surgery Center, Athens, Greece

EVALUATION O F MYOCARDIAL D I S T R I B U T I O N OF I O D I N E - 1 2 3 M E T A I O D O B E N Z Y L G U A N I D I N E (12~IMIBG) IN ATHLETE'S HEART T Hata, R Nohara, R Hosokawa, M Fujita, S Sasayama Kyoto University Hospital, Kyoto, JAPAN

Iodine-123 metaiodobenzylquanidine(M1BG) imaging has been used to demonstrate regional sympathetic innervation of myocardial tissue in various clinical and experimental settings. There is no data on cardiac sympatheticinnervationfollowingcardioplegiaand cardiac surgery. In order to assess this, we studied l0 patients who underwent cardiac surgery, by MIBG uptake t day prior to operation and 1 week and 6 months following surgery. MIBG uptake was quantified by heart'lung ratio on planar images 4-5 hours post injection. Regional uptake was estimated in 20 segments of the tomographic images by using a 4 point scoring system (0=normal and 4=no uptake). One week followingsurgery heart/lung ratio of MIBG uptake decreased significantlyfrom 1.18+0.32 to 0.76_+0.22,p=0.004. In 6 months the reduction of the hearfflung ratio of the MIBG uptake was restored (0.76_+0.22 to 1.10+0.28, p=0.004). The total MIBG score also improved from one week to six months following surgery from 6.0_+3.7 to 3.5+3.2 (p=0.003). In conclusionwe observedthat cardiac surgery is associatedwith a significant reduction of myocardial sympathetic innervation in the postoperative period. This reduction was restored back to normal levels six months after cardiac surgery. The clinical significance of this observation needs further investigation.

It remains unclear whether increase in cardiac extraneuronal volume due to physiological left ventricular hypertrophy like athlete s heart affects cardiac 123I-MIBG uptake and clearance (CR) or not. To clarify this problem, 13 young athletes (mean age 24+6) with normal cardiac function were studied. Planar imaging was obtained at 15 min and 3 hours (3H), and S P E C T waslz~ also performed 3H after injection of 111 MBq of I - M I B G , and counts were corrected by input function. Left ventricular (LV) mass was also evaluated using 2-D echo simultaneously. And then correlation coefficients (CC) of myocardial mI-MIBG uptake and clearance with LV mass were investigated. CC of MIBG uptake with LV mass at 15 min (15) and 3H were 0.68 and 0.001, and uptake per pixel with LV mass 0.27 and -0.20, respectively. CC of heart/mediastinum ratio to LV mass at 15 and 3H were 0.28 and -0.61, respectively. CC of CR with LV mass was 0.59. All these values except of m l - M I B G uptake (3H) were statistically significant. Thus, LV mass affected these factors clinicaly used in evaluation of :~I-MIBG uptake, indicating that it is necessary to take into account the effects of hypertrophy for quantitation of cardiac ~23I-MIBG imaging.

M O N D A Y

A M A P R I L

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Abstracts Monday morning, April 7, 1997

8.30 M O N D A Y A M A P R I L 7

Journal of Nuclear Cardiology January/February 1997, Part 2

8.32

REGIONAL HETEROGENEITY OF OXYGEN METABOLISM IN N O R M A L H U M A N HEARTS N. Hattori, T. Kudoh, I. Masuda, Y. Magata, H. Kitano, M. Inubushi, K. Nakao, N. Tamaki, J. Konishi, Kyoto University, Kyoto, Japan

SEVER'ELY IMPAIRED CORONARY RESERVE RATHER THAN RESTING HYPOPERFUSION CHARACTERISES HIBERNATING MYOCARDIUM Farzin Fath-Ordoubadi, Kevin J Beatt, Paolo G Camici. MRC CSC and RPMS, Hammersmith Hospital, London, UK.

To evaluate the heterogeneity of regional oxygen metabolism of normal human hearts, dynamic PET with C 11-acetate was performed at rest (R) and under the dobutamine stress (DB) for 11 subjects (8 men, 3 women: mean age 49.5_+14.8) without coronary artery disease. The clearance constants of C l l - a c e t a t e (Kmono) were calculated in the 5 segments of myocardium including apex (APX), anterior (ANT), lateral (LAT), inferior (INF) and septal (SEP) walls. The regional differences of Kmono were compared at R and under DB. Of all 5 segments, Kmono of ANT and SEP showed greater values, and those of INF showed smallest values botb at R and under DB. The difference was more evident tinder DB, and paired t-test confirmed significant difference between ANT and INF (p < 0.01). APX ANT LAT INF SEP Rest 6.3+1.7 6.8_+1.5" 6.6+1.4 6.2+_1.3" 6.9_+1.6 Stress 9.8-+1.9 10.4+_2.i** 9.9_+2.1 9.0_+1.8"* 10.0-+1.9 (Mean _+S.D., *p<0.01, **p<0.001) In conclusion, normal human hearts have heterogeneous oxygen metabolism with smallest value in its inferior wall. It is enhanced under the beta adrenergic stress, and may be related to the beta adrenoceptor density.

Recently the concept that myocardial (M) hypoperfusion is the cause of M hibernation has been challenged. Aim of this study was to test the hypothesis that a severely impaired coronary vasodilator reserve (CVR) rather than a reduction of resting myocardial blood food (MBF) characterises hibernating (H) myocardium. We studied 18 patients [(pts), age 62-+9 years] with at least one chronically dysfunctional M segment (S) subtended by a stenotic coronary artery. Using positron emission tomography (PET) and JsO-labelled water, MBF (ml/min/g) was measured at rest (rMBF) and after dipyridamole (dMBF, 0.56 mg/kg); the metabolic rate of glucose (MRG, lamoi/g/min) was measured using lSF-fluorodeoxyglucose and PET during euglycemic hyperinsulinemic clamp. All pts had successful revaseularization (R) by angioplasty (PTCA). Left ventricular function was assessed by echocardiograhy before and 3-6 months after PTCA. In 9 pts a repeat MBF study was performed 3-6 months after PTCA. Before R normal :and H-S had comparable rMBF (0.9-+0.23 v s 0.89-+0.3) and MRG (0.4+0.13 vs 0.4-+0.l) while CVR (dMBF/rMBF) was lower in H-S although this difference fell short of statistic significance (1.98_+I.08 vs 1.68-+0.77). In the 9 pts who had a repeat PET after PTCA, there was no change in rMBF both in normal and H-S (0.87-+0.27 Vs 0.76_-z-0.19) whereas CVR improved in H-S (2. I-+1.05 Vs 2.25+ ! .35, p=0.06 vs prePTCA value). Multivariate regression identified MRG (p<0.001), but aot rMBF to be the predictor of functional outcome. In conclusion., these results seem to indicate that a reduced CVR, which improves upon R, but not resting hyr)operfusion characterises H mvoeardium.

8.31

8.33

BASELINE LEFT VENTRICULAR PERFORMANCE AND RECOVERY AFTER REVASCULARISATION: PREDICTIVE VALUE OF ABSOLUTE tSF-FLUORODEOXYGLUCOSE UPTAKE F Fath-Ordoubadi, D Pagano NVS Marinho, BE Keogh, , RS Bonser PG Camici. MRC CSC, RPMS, Hammersmith Hospital, London, UK. To assess the relation amongst the severity of baseline (B) left ventricular (LV) dysfunction, myocardial glucose utilisation measured with tSF-fluorodeoxyglucose (FDG) positron emission tomography (PET), and functional recovery after revascularization (R), we studied 47 patients (pts) with coronary artery disease and chronic LVdysfunction. All had radionuclide ventriculography (RNV) and FDG PET during euglycaemic hyperinsulinaemie clamp (EHC) and repeat RNV 6 montbs after R. Two Groups (G) b&~ed on the B ejection fraction (EF), were identified: GI, EF<28% (n=22; age: 58-+10); G2, EF>28% (n=25; age: 62-+7). The proportion of dysfunctional (D) S in G1, 122/169 (72%) was greater than in G2, 78•200 (39%; p<0.001). LV-EF after R improved by 8-+9% (p<0.001) in GI but not in G2. Wall motion score (WMS) improved both in G1 (2.08±0.4 to 1.6±0.35. p<0.00l) and G2 (1.49+0.4 to 1.33-+037; p=0.01). The Metabolic Rate of Glucose [MRG, 0amol/min/g)] in normal S was 0.43+0.14 in G1 and 0.46+0.18 in G2 (p=NS). The MRG was greater in D-S of Gl compared to G2 (0.44-+0.15 vs 0.38-+0.16, p=0.01). Predictive accuracy (PA) of FDG PET varied according to the MRG threshold value chosen and the B-EF. In pts with EF<28% the negative PA of FDG PET for S with MRG values of <0.22 was 100%. Conclusiuns: 1) LV functional improvement after R is more likely in pts with EF<28%. 2) The MRG during EHC is higher in D-S of pts with EF<28% suggesting thai overall there is a greater mass of recoverable myocardium. 3) Quantitative FDG PET has a very high negative PA in pts with severe LV-dysfunctioa

u C-LABELLED ENERGY SUB STRATES FOR THE DIAGNOSIS OF EXERCISE INDUCED I S C H E M I A

S. Valind t'2, B. Lagerquist 3, R. TakatJ '2, B. I_Angstr6mI Uppsala University PET Centre a, Department of Cardiology3 and Department of Clinical Physiology2, University Hospital Uppsala

Myocardial hypoxia results in metabolic changes such as a shift in the redox state (NAD+/NADH), ATP depletion and inhibition of pyruvate dehydrogenase (PDH), all of which will affect the intracellular pathways of short chain monocarboxylic energy substrates. In a pilot study we have measured the initial myocardial uptake of l tC-labelled (methyl position) acetate (ACT), pyruvate (PYR) and lactate (LAK) with PET in patients (3 for each tracer) with stable exercise induced angina. Studies were made at rest (including perlhsion measured with Hz150) and following a symptom limited exercise test. The myocardial extraction of tracer at rest was similar for ACT and L A K (mean:62 and 49%) but slightly lower tbr PYR (34%), resulting in a 11C myocardium/blood ratio of 7.6, 5.7 and 4.2, resp. The largest reduction in tracer uptake at peak exercise (mean of 3) was 25(ACT), 36(LAK) and 48% (PYR), compared to non-ischemic parts of the heart. W e conclude that the invivo performance of these tracers supports their use in the diagnosis of coronary artery disease.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Monday morning, April 7, 1997

8.34

8.36

THE FREQUENCY & IMPACT OF FINDING HIBERNATING MYOCARDIUM IN CARDIAC TRANSPLANT CANDIDATES (TXPT). V. Kalff, B. Van Every, JL .Rowe, D. Esmore, P. Bergin, MJ .Kelly. AlfredHospital,Melbourne,Australia.

VARIOUS COUPLING BETWEEN GLUCOSE METABOLISM AND CONTRACTION IN STUNNED MYOCARDIUM AFTER ACUTE MYOCARDIAL INFARCTION D.S. Lee, J-K. Chung, I.H Chae, B.H Oh, M.C. Lee, J.D. Seo, C-S. Koh. Scoul National University Hospital, Seoul, Korea

28 TXPT with coronary disease(CAD) & 16 other CAD (NOT)() patients(pts),were assessed for perfusion/metabolismmismatch (MM) with rest 4 view, planar myocardialTI-201 & F-18 fluorodeoxyglucose(FDG)scans on a modifiedgamma camera. MM was sized using a 0-3 scale for each of 4 vascular regions, values were addedto give each pt a global MM score(0-12). MM extent & incidence was compared in the TxPT & NoTX groups. The effect of MM on TXPT management[cardiactransplant,coronary surgery (CABG), no surgery]was reviewed 6 monthspostscan. Results: TXPT had fewer MM (8/28 vs 9/16 pts), a lower global MM score (14/336 vs 22/192; p<0.01) & mean LVEF (20+8% vs 33+_15%;p<0.001), than NoTX pts. TXPT with LVEF<20% had fewer MM (3t16 vs 5t12 pts) & lower global MM score (3/192 vs 111144; p<0.02) than TXPT with LVEF>20%. 2/3 NoTX pts with LVEF<20% had MM (global MM scores of 2). Follow-upstudies showed 0/3 TXPT havingCABG had MM and transplan~onwas offered to 1 of only 2 TXPT with significantMM (score:>_2). Conclusion: Because TXPT have a very low MM incidence & clinical decisions are based on many factors, FDG imaging in TXPT may be of limited value, parUculadyif LVEF is below 20%.

Restored perfusion meant viability in acute myocardial infarction, however, poor contractility in stunned myocardium was either due to poor efficiency despite preserved metabolism or due to decreased metabolism itself. We prospectively investigated glucose metabolism and their coupling with flow and contraction in acutely stunned myocardium. In 14 patients with acute myocardial infarction, 2 did not improve and were excluded. Among 12 patients, 7 patients were found to have stunned myocardium, whose thallium uptake was normal either at rest or at 24-hour delay SPECT. Wall motion was proven to be improved 4 to 10 weeks later. Four patients showed normal glucose metabolism, and the other 3 showed much decreased metabolism in contrast to normal perfusion. Decreased perfusion/ preserved metabolism mismatch was found in 3 patients, whose myocardium were thought to be acutely hibernating. After revascularization (8 PTCA, 2 CABG), wall motion abnormality and ejection fraction were improved (11+5.5%). Negative predictive value of decreased metabolism was only 40% because of this 'reverse mismatch (preserved perfusion aud decreased metabolism). This observation implied that there were spectrum of coupling between perfusiolv'metabolism/contraction in acute myocardial infarction. Decreased glucose metabolism should not be referred as an evidence of non-viabilityin acute myocardial infarction.

8.35

8.37

USEFULNESS OF POSITRON EMISSION TOMOGRAPHY (PET) IN ISCHEMIC HEART DISEASE : FOCUSING ON MYOCARDIAL VIABILITY BEFORE AND AFTER PTCA K.Masuyama, N.Takekoshi, H.Seki, S.Kancmitsu, M.Kitayama, S.Minra, Kanazawa Medical University, Ishikawa, Japan.

QUANTITATION OF M Y O C A R D I A L F-18 DEOXYGLUCOSE U P T A K E P R E D I C T S W A L L MOTION RECOVERY AFTER CABG S. Husain, J. Gona, J. Sodhi, L. Levinsky, E. Campos, D. Lamonica, A. Shad, P. Galantowicz, M. Merhige, SUNY at Buffalo, U.S.A.

Purpose: In the present study we used 13NH.~and 18FDGPET in patients with ischemic heart disease before and after PTCA to evaluate myocardial viability based on myocardial blood flow and glucose metabolism, and investigated changes in energy metabolism before and after the revascularization procedure. Subjects and methods: The subjects were 47 non-diabetic patients with angina pectoris or myocardial infarction with lesions in one vessel of the coronary artery in whom PTCA was successfully performed and who showed no restenosis on CAG 3 month later. LVG, CAG, -'°ITI(STRESS, Re-inj), and resting, fasting PET (laNH3, ~SFDG)were performed 7 "~ 14 days prior to PTCA and within 3 months thereafter. Results: In the 21 patients with angina pectoris defects on 13NH3PET were found in 21/21 cases (100%) consistent with the culprit coronary artery on preoperative and post PTCA CAG and in these sites of defects acceleration of I~FDG uptake was noted making possible a diagnosis of ischemic and viable myocardium. In 9 of 16 MI cases in which the preoperatively non-viable myocardium was judged to be able by 2°1T1SPECT, after the PTCA, improved wall motion in conjunction with increased blood flow(PET), was observed. Summary: In patients with ischemie heart disease, especially those with MI, determination of myocardial viability by PET is important in deciding the indications for PTCA.

To determine if quantitation of F- 18 deoxyglucose (FDG) uptake identifies akinetic segments which recover wall motion (WM) after revascularization (CABG), we measured FDG uptake inl 1patients (pts) prior to CABG and scored WM from zero (normal) to 5 (dyskinetic) in pre and post op gated ventriculograms. LVEF improved in 6 pts (0.32 + 0.10 to 0.49 + 0.11; p<0.00 I). In the 10 akinetic segments which recovered WM (Group 1), preop FDG uptake was significantly higher than in the 7 segments which did not (Group 2), despite technically successful revascularization. Wall Motiml Score

Preop FDG Uptake

0.56 - 0.91 0.24 - 0.46 Concl: Functional recovery occurs in akinetic segments alter CABG when FDG uptake exceeds 50% of peak myocardial activity.

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M O N D A Y A M A P R I L 7

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M O N D A Y A M A P R I L 7

Abstracts Monday morning, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

8.38

8.40

POLARMAPS OF MYOCARDIAL BLOOD FLOW FROM DYNAMIC [O-15]WATER PET-STUDIES. F. Hermansen, P.G, Camici and A.A. Lammertsma, Cyclotron Unit, MRC Clinical Sciences Centre, Hammersmith Hospital, London, UK.

CONSTANCY OF MYOCARDIAL BLOOD FLOW AND PAIN PERCEPTION OVER TIME IN PATIENTS W1TH SYNDROME X SD Rosen, H Boyd, *J-C Kaski and PG Camiei. MRC-CSC/RPMS, Hammersmith Hospital and *St George's tlospilal, London, UK.

The purpose of the present study was to develop a method with substantially improved precision for calculation of myocardial blood flow (MBF) with [O-15]water and PET. Methods Two linear combinations (representing essentially flow and tissue volume) of the dynamic sinograms were reconstructed iteratively providing two low-noise images. MBF polarmaps were generated as the quotient in 109 ROIs of these images and corrected for non-linearity. The results of the present method were compared with those of traditional non-linear regression in both normal and hyperemic states of three patients with coronary artery disease (CAD). Results The noise was 2.5 + 0.4 times lower (P<0.0001) with the new method. MBF values were similar although not identical with the two methods. The hyperemic polarmaps showed the expected flow patterns for the CAD patients. Conclusions The new method reduces substantially the noise in MBF measurements. Further studies are needed for validation.

8.39 CORONARY FLOW RESERVE DETERMINATION AFTER HEART TRANSPLANTATION M. M. Kbrner, D. Bailer, N. Kromer, G. Gleichmann, G. Notohamiprodjo, R. Koerfer Heart Center NRW, Ruhr University of Bochum, 32545 Bad Oeynhausen, Germany To measure the coronary flow reserve (CFR) in 14 heart transplant recipients (HTx) (group A) calculation of myocardial blood flow (MBF) was performed by the N-13 ammonia PET (Siemens ECAT-951]R) following i.v. application of I015 mCi N-13 ammonia at rest and after pharmacological determination of coronary vasodilation reserve. CFR was calculated as MBF-dipyridamole/basal MBF ratio. Reference: 7 patients (group B) with normal CFR and coronary angiograms and 23 patients (group C) with angina pectoris withoutlwith minor angiographic coronary disease. Results (mean values ± standard deviation): Mean CFR was significantly reduced in HTx with 1.6 • 3 compared to group C: 2.5 ± 0.7 and compared to B: 4.7 ± 0.8. The dipyridamoleinduced mean coronary flow was: 200 ± 71 in HTx compared to 199 ± 45/ml]min I00 g in C and 396 ± 59 in B.

In HTx the determination of CRF by PET contribute to objectifying or excluding a limited blood flow regulation.

We previously investigated patients with syndrome X [SX, angina, isehaemie-like changes in the stress electrocardiogram (ECG) and a :normal coronary arteriogram] and found no relationships amongst m y ~ d i a l blood flow (MBF), ECG changes and pain perception after dipyridamole challenge (D). To assess the stability of these parameters, we repeated the investigationS, (identical technique), in 14 SX, 9 female, age [mean (SD)] 52 (8) years. MBF (ml/min/g) was measuredat rest (R) and after intravenous D (0.56 mg/kg over 4 rain) using positron emission tomography (PET) with H2150 -: Chest pain 'was noted as P+ , its severity scoredon a 0--10 scale (pain score). The reinvestigation (Study II) took place 212 (251) days after the original study (Study 1) and ,after 10 days' placebo therapy. MBF(R) did not differ between the studies: 1.16 (0.41) in study I vs 1.20 (0.26) in Study IL Resting MBF was cbrrected for heart rate (HR) x systolic blood pressure (SBP) as: MBF(Corr) = MBF(Rest)xl04/(HRxSBP). MBF(Corr) was unchanged; 1.34 (0.35) in Study I vs 1.43 (0.37) in Study II, p=NS. MBF(D)was also comparable: 3.11 (L08) in study I vs 3.65 (1.13) in study II. Corrected coronary vasodilator reserve [MBF(D)/MBFCorr)] was unchanged: 2.38 (0.75) vs 2.64 (0.85), p=NS. Pain score tended to be lower in Study II: 4.2 (3.2) vs 3.0 (3.0), p=O.07. In Study I as in Study If, no relationships were fotmd amongst MBF, ECG changes and P+. In conclusion, MBF values me in the normal range in SX patients [Normals: (n=20, age 51(15) years, p=NS vs patients) MBF(R) 1.00 (0.22), MBF(D) 3.00 (1.00), MBF(Corr) 1.34 (0.29), CVR 3.06 (1.08), CVR(Corr) 2.34 (0.90)]; MBF and CVR remain stable over time. The placebo may influence pereeivedchest pain in SX.

8.41 DIRECT COMPARISON OF N-13 PET AND SESTAMIBISPECT PERFUSION IMAGING IN SEVERE CHF PATIENTS.

M.Bottcher, N.P.Sand, M.M.Madsen, T.T.Nietsen, M.Rehling. Dept. of Card. and dept. ofNucl. Med., Aarhus Univ. Hosp., Denmark PET-scanning enables detection of myocardial viability. Due to the limited availability of PET facilities it has been proposed to combine Sestamibi-SPECT with FDG-PET. A prerequisite for this is that PET and SPECT yields similar perfusion scans. Thirty-one patients (57+8 years, mean EF 27+8%) with verified CAD were included. In random order perfusion scans using Ammonia-PET and Sestamibi-SPECT were performed. Two blinded observers scored a total of 610 segments on a 5-point scale in a 20 segment model of the left ventricle. Segmental score-differences (SPECT-PET) in % of the total number of segments are show~: . 0 -1,0rl >2 < -2 No, Segm K Anterior# 43 71 19 10 90 ' Lateral# 60 86 4 10 185 iI Ai}i_e.ai# 38 82 13 5 61 [ 0.53# I Septal + 42 68 28 4 185 I 0.33+ Posterior+ 25 63 32 5 89 ! 0.42 Overall 45 75 18 7 610 # and + represent weighted kappa (•) for pooled data of regional groups. The repeatability for SPECT and PET, (-l,0,1)-values, were 94% and 92%, respectively. In conclusion PET mid SPECT perfusion scans yield similar results, except for the septal and posterior regions, where SPECT tends to overestimate perfusion defects, most likely due to attenuation artifacts. Hence attenuation correction should be considered when combining FDG-PET and Sestamibi-SPECT for diagnosing myocardial viability.

Journal of Nuclear Cardiology V o l u m e 4, Number 1, Part 2

Abstracts Monday morning, April 7, 1997

8.42

8.44

SYSTEMIC ARTERY DILATORY CAPACITY AND MYOCARDIAL PERFUSION RESERVE IN NORMALS M.Bottcher, M . M a d s e n , K.Sorensen, T.Toftegaard, J . C z e m i n . Dept. of C a r d i o l o g y B. A a r h u s Univ. Hosp., Denmark.

M Y O C A R D I A L BLOOD FLOW REGULATION IN INFARCTED PATIENTS WITH STRESS-INDUCED NORMALIZATION OF NEGATIVE T WAVES,

Ultra sound (US) e v a l u a t i o n of s y s t e m i c artery vasodilatory c a p a c i t y is w i d e l y a v a i l a b l e and a p o s s i b l e w a y to detect early signs of C A D . However, little is k n o w n a b o u t the correlation

S 15

A.Giorgetti, G.Sambuceti, D.Neglia, N.Nista, A.Gimelli, O.Parodi. CNR Institute of Clinical Physiology, Pisa, Italy.

peNS) nor with the myocardial perfusion response after NTG (re0.01, peNS). The lack of correlation between the two techniques indicate different mechanisms controlling these factors.

The correlation of stress-induced normalization of negative T waves (NTW) with regional myocardial blood flow (MBF) regulation and tissue viability remains still dented. To clarify its meaning, 14 patients with previous myocardial infarction (13 Q waves) and negative T waves on baseline ECG and 10 normal subjects were studied by means of positron emission tomograghy and N-13 ammonia, at rest and after dipyridamole infusion. Scintigraphic segments with baseline echocardiographic dysfunction were identified as the correspondent infarcted regions of NTW (G1, n=42) or persistent negative T waves (G2, n=60) observed during dipyridamole ECG test. Resting MBF was similar between G1 and G2 (.53+.18 vs .584-.27 mL/mirdg, respectively, PENS) and significantly lower than in normals (1.07+.28 mL/min/g, P<.01). Following dipyridamole, MBF was significantly higher in G1 than in G2 (1.03+.69 vs .73+.48 mL/min/g, respectively, P<.01) and markedly lower than in normals (4.074-1.03 mL/min/g, P<.01). Thus, in infarcted dysfunctional areas stress-induced NTW demonstrates better MBF availability than persistent negative T waves despite similar values of resting perfusion, suggesting a better preserved coronary microcirculatory function.

8.43

8.45

DOES RADIOFRBQUENCY CATHETER ABLATION (RFCA) INDUCE A DETERIORATION IN SYMPATHETIC INNERVATION?

THE RATE-PRESSURE-PRODUCT AS A DETERMINANT OF MYOCARDIAL BLOOD FLOW DURING DIPYRIDAMOLE STRESS IN HEALTHY, YOUNG VOLUNTEERS C, Meyer l, K. Kofoed 2, J, Hove2, R.B. Schambye t, S. Carstensen 2, H. Kelb;ek2 and B. Hesse t. National University Hospital, Rigshospitatet,

between vasodilatory capacity of systemic arteries and the myocardial perfusion reserve (MPR). We studied 24 volunteers (25+5 years) with low likelihood of CAD. Using dynamic PET we measured MPR after oral nitroglycerin (NTG, 4001-tg) and after dipyridamole (0.56 mg/kg/min). Data were compared with US data of brachial artery vasodilatory capacity expressed as increase in cross sectional diameter after NTG 4001.tg.

!:i ' "" m-6 ul= (% ol b = ~ . ~ v ~ . ~ )

C o n c l u s i o n : Periferal dilatory c a p a c i t y does not correlate w e l l w i t h neither the d i p y r i d a m o l e i n d u c e d h y p e r e m i a (re0.01,

I.Kosa, C.Schmitt, C.Meyer, S.Weyebrock, A.Plewan, M.Schwaiger. Nuldearmedizinische Klinik, Technische Universitit, Miinchen, Germany RFCA is effective treatment for reentrant tachycardias because it destroys malignant accessory pathways. An eventual parallel destruction of sympathetic nerves may, however, create new sources of arrhythmias due to the induction of inhomogeneity in sympathetic tone. To describe the effect of this therapy on sympathetic innervation we investigated 6 patients using C-1 lhydroxyephedrine fliED) - PET and N-13-ammonia -PET. The studies were performed before and 2 to 6 weeks after RFCA. In addition to visual analysis, HED retention was quantified in the myocardial quadrant distal to the location of intervention (DO; these results were compared with values in remote areas fRA). Before RFCA, myocardial perfusion showed homogeneous distribution in 5 of 6 patients. One patient demonstrated a perfusion defect in the posterior wall. HED retention matched perfusion distribution in all patients. After RFCA there was no significant change observed either in ammonia or in HED distribution. Quantitative I-IED retention data from 5 patients showed no significant change before vs. after RFCA either in DI or in RA (8.0 4- 3.0% vs. 9.5 4- 3.7% and 8.2 + 2.7% vs. and 9.8 4- 3.0%, respectively). Thus, HED-PET does not demonstrate any abnormalities of tracer uptake in sympathetic nerve terminals indicating integrity of autonomic innervation following regional ablation therapy.

Copenhagen, Demnark. Several studies in elderly patients have shown a significant correlation of the rate-pressure-product (RPP) to myocardial blood flow (MBF) at rest as well as duling cold presser stress. However in this population, no such relation has been shown during dipyridamole. We studied 23 young, healthy, male volunteers (age 29±4 years), all non-smoking, non-hypertensive, with normal levels of blood glucose and cholesterol, in whom cardiac disease was excluded by history and exercise ECG, with positron emission tomography (PET) and 13N-Ammonia at baseline, during a Cold Presser Test (CPT) and after coronary vasodilation with dipyridamolc (DIPY). All resuIts are expressed as mean +-SD. Rest CPT DIPY Heart Rate 61 ±11 69+-11 86+-12 Systolic Blood Pressure 118+-10 135±13 129+-13 Diastolic Blood Pressure 52+-9 70±10 61 _+9 Rate-Pressure-Product 7191+-1634 9403+-2065 11136+-.2129 Myocardial Blood Plow 0.60±0.15 0.76_+0.21 1.91+-0,63 The correlation between RPP and MBF was r = 0.79 (p<0.001) at rest, r = 0.65 (p < 0.01) during CPT and r = 0.75 (p<0.00t) during DIPY. The correlation beween the ratios of MBFept/MBFr~t and RPPept/RPPr~st was r = 0.79 (p<0.001) and between ratios of MBFdlp~ClBFr=~tand RPPaip/RPPr:~t was r = 0.80 (p<0.001). Conclusion: Our results indicate a close relationship between the RPP and MBF during dipyridamole in young, healthy volunteers, which contradicts the assumption, that hyperemic MBF is independent of myocardial oxygen consumption during dipyridamole.This is possibly due to an age-dependant difference in the effect of dipyridamole.

M O N D A Y A M A P R I L

S 16

M O N D A Y

A M A P R I L

Abstracts Monday morning, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

8.46

8.48

RELATIONSHIP BETWEEN MYOCARDIAL BLOOD FLOW RESERVE AND ENERGY METABOLISM IN PATIENTS WITH IDIOPATHIC HYPERTROPHIC CARDIOMYOPATHY (HCM) Y. Ishida, S. Nagata, T. Uehara*, N. Yoshimura, Y. Hirose, Y. Shimotsu, Y. Miyake, Y, Yasumura, K. Miyatake, T, Nishimura* National Cardiovascular Center and *Osaka Univ., Osaka, Japan

USE OF DIGITAL PHANTOMS TO STUDY THE TRANSMURAL DISTRIBUTION OF TRACERS BY PET L. Livieratos, H.L. Boyd, O. Rimoldi, P.G. Camici. MRC-CSC and RPMS, Hammersmith Hospital, London, UK

We studied regional myocardial flow reserve by dipyridamote (DP)-stress ~3N-ammonia (~NH s) PET, free fatty acid utilization by fasting ~231-BMIPP(~}-methyl iodophenyl pentadecanoic acid) SPECT and glucose utilization by fasting ~SFDGPET in 20 HCM patients with asymmetric septal hypertrophy and without perfusion defects at rest (IVSth=19±5 mm, PWth=l 1±4 mm, 53+20 years). In the midventricular transaxial tomogram, we determined tracer distribution ratio between septal and lateral regions (S/L) after correcting the partial volume effect. ~NH 3 S/L at rest was 1.05:~0.16 indicating homogeneous flow distribution between both regions, but ~NH 3S/L during DP showed lower value (0.82±0.23, p<0.01 ) than that at rest indicating relatively reduced flow reserve in septal regions. Nine of the patients showed septal BMIPP defects (BMIPP S/L=0.70±0.05) and showed significantly lower ~3NH3S/L during DP (0.75±0.12, p<0.01) than the remaining 4 patients without BMIPP defects (1.04±0.10). BMIPP S/L correlated well with ~=NH3 S/L during DP (r=0.55, p<0.05) and the extent of the change from rest to DP (r=0.73, p<0.001). However, ~SFDG S/L did not correlated with ~3NH3S/L at rest and during DP, and BMIPP S/L. These results suggest that reduced myocardial flow reserve is important as an inducing factor of myocardial metabolic abnormality, particularly in the free fatty acid utilization in HCM patients.

Myocardial isehemia is more severe in the subendocardium (ENDO) compared to the subepicardium (EPI) which leads to an uneven transmural distribution of tracers. By means of digital phantoms we have studied the effect of differefit wall thicknesses and ENDO]EPI radioactivity ratios on the recovery coefficient (RC) of counts which were obtained simulating the characteristics of a 931 08/12 PET scanner. As expected the RC increased as a function of wall thickness at every ENDO/EPI ratio although the RC was always greater in the ENDO than in the EPI. However, the relation between the RC and wall thickness was not affected by changes in the ENDO/EPI ratio when the full wall thickness was considered. endo/epi

retic= i

endo,/epi

o.c,

~

o.oi

0

.'.'0 40 60 grJ IOO CCrC[OC wolf [hicln {;~r~)

O

rctlo= 0.5

..................... 20 40 5C, ,f:O CO/'(]i{*'C ~,¢sl[ [!l;Ck~. f'~:l"')

1C~

In conclusion: 1- There are transmural differences in the RC which might be due to spillover; 2- This will affect the measured ENDO and EPI activity concentrations and appropriate corrections should be applied.

8.47

11.1

HOMOGENEOUSLY VERSUS HETEROGENEOUSLY IMPAIRED REGIONAL MYOCARDIAL BLOOD FLOW IN HYPERTENSIVE PATIENTS: RELATIONSHIP WITH MYOCARDIAL HYPERTROPHY. A. Gimelli, J. Schneider-Eicke, D. Neglia, A. Giorgetti, G. Bigalli, G. Parodi, G. Sambueeti, O. Parodi. CNR, Clinical Physiology Institute, Pisa, Italy.

MYOCARDIAL CONTRAST ECHOCARDIOGRAPHY VERSUS SESTAMIBI-SPECT FOR THE DETECTION OF CORONARY ARTERY DISEASE Roxy Senior, Avijit Lahiri, Howard Dittrich, Usha Raval, Raj Khattar, Sanjiv Kaul. Northwick Park Hospital, Harrow, England, UK Thirty patients with known or suspected coronary artery disease (CAD) underwent myocardial contrast echoeardiography (MCE) and sestamibi SPECT at baseline and after 0.56 mgokg4 of dipyridamole. Ten segments from the baseline and post-dipyridamole images were analyzed separately for the presence of myocardial perfusion by both methods using the following scores: 1--normal, 0.5=mildly reduced, and 0=severely reduced. The combined information from both baseline and post-dipyridamole images was then used to determine whether an abnormal segment was reversible or irreversible. Concordance between segmental scores was 92% (kappa=0.99) for both methods. Concordance between normal perfusion and reversible or irreversible segmental defects was 90% (kappa=0.80). Agreement between the two methods for each of the 3 vascular territories in each patient was 90% (kappa=0.77), while agreement for the presence or absence of coronary artery disease in each patient was 86% (kappa=0.86). It is concluded that MCE using venous injection of contrast is comparable to sestamibi SPECT for the detection of CAD.

The effect of left ventricular hypertrophy on regional vasodilating capability is still controversial. To this purpose, baseline and dipyridamole myocardial blood flow (MBF) were measured using N-13 ammonia and positron emission tomography, in 50 untreated hypertensive patients without coronary artery disease and 13 normals. Left ventricular mass was assessed by eehoeardiography. Hypertensive patients showed similar MBF as normals (p=ns) but reduced values after dipyridamole (p<.05). This impairment was not correlated with hypertrophy (p=ns). Among hypertensive patients, a group with homogeneous and one with heterogeneous distribution of peffusion-',ffter dipyridamole were identified. In the former group flow was globally reduced, while in the latter it was abnormal only at the site of the perfusion defects. Patients with regional defects showed the highest, likelihood of having an elevated left ventrieular mass. In conclusion, left ventricular mass was not correlated with global myocardial blood flow. Nevertheless hypertrophic patients are likely to show an heterogeneous flow pattern with regional defects and almost normal blood flow in non affected regions.

Journal of Nuclear Cardiology V o l u m e 4, Number 1, Part 2

Abstracts Monday morning, April 7, 1997

11.2

S 17

11.4

EFFECTS ON DIAGNOSTIC ACCURACY OF MYOCARDIAL SPECT OF TRANSMISSION/EMISSION ATTENUATION CORRECTION. M.DONDI; P.L.GUIDALO'I3"I; R. CASANOVA; A.L. PATRONCINI; S.FANTI; P.F.CAPACCI; A. MARESTA. Nuclear Me~cine Service and Division of Cardiology; Ospedale per gli Infermi, Faenza (RA), Italy This study aimed at evaluating if transmission/emission attenuation correction may increase dagnostic capabilities of SPECT. We used a threeheaded camera and a simultaneous transmission/emission aoopisition to produce a double series of tomographio studies, attenuation corrected (AC) and non-attenuation corrected (NAC) for each patient. We applied a segmental analysis (29 segments) and a qualitative 5-point score (0=norrflal; 4=no uptake). Overall 60 patients (48 males; 12 females) were submitted to coronary angiography and are the subjects of the present study. Significant CAD (stenosis >_70%)was found in 51 pts. LAD was involved in 27 cases, RCA in 24 and CX in 30. Singta-~,~sseldisease (1VD) was detected in 28 pts, two-vessel disease {2VD) in 16 and ~hree-vessel(3VD) in 7. Out of the 9 pls with all patent vessels, CAD was correctly ruled out in 8/9 (spac 89%) by AC-studtes and in 5/9 (spat 56%) by NAC-studias. AC-studies identified 1VD in 24/28 cases (86%); 2VD in 9116(56%) and 3VD in 6/7 (86%). NAC-studies identified lVD in 15/28 (54%); 2VD in 8/16 (50%) and 3VD in 2/7 (29%) of cases. Stenotic arteries were identified as follows: SENS

AC-atudiea SPEC

SENS

NAC-studies SPEC

IMPACT OF TRANSMISSION-EMISSION ATTENUATION CORRECTION ON MYOCARDIAL SPECT SPECIFICITY IN A POPULATION AT LOW-RISK FOR CAD. S.Fanti, M.Dondi, P.L.Guidalotti, S.Zoboli, A.Romeo, C.Corbelli, N.Monetti. Nuclear Medicine Dpt, S.Orscia-Malpighi Hospital, Bologna, Italia. Photonattenuationin the chestdeterminesalJfactualabnormalitiesof relativeb'acer dis~u6on in myoca-dialSPECT(M-SPECT),and attenua~onis retainedto be one of the majorcauseof falsepositivecetdiecperfusionimaging.In order to assessthe impactof attenuationcorrectionon M-SPECTspecificity,we evaluatedthe studiesof 67 consecutivepatientsat low prd~bility for CAD (< 5%). out of the population referredfor sb'eea+restM-SPECT.We employeda three-headcameraequipped~th a commercially available nnsmieaioNemission device. A double series of tor~ic studies,attonuationcorrected(AC) and non attenua~oncorrected(NC), were reconsltuetedand analysedadopting a qealitatJve5-point score (0=normal; 4=no uptake), For each myocardialwall a total score and a mean sege~ental score was calculated, We consideredas false positiveall studieswib 2 or more segments

scored;P_2.Resultsare detailedin tab.1.After attenuationcorrectionsegmentsof the TABLE1 TOTAL SCORE infadorand septet walls stressNC .restNC ;stressAC restAC showed a significant ANTER 28 22 40 35 decreaseof their scores APEX

INFER SEPT LATER

.... 69

15t 130 51

53 139

77 82

75 64

(p<0.05), while segmentsof the anterior

126

63

58

wall showed a mild

38

42

31

increase o[

score,

CX 87% (26/30) 96% (27/28) 73% (22/30) 96% (27/28) In ~g~.lusions, attenuation correction increased diagnostic a~curacy of SPECT, improving bofh sensitivity and specificity. This approach seems to be a definite improvement of myocardial SPECT.

though the change did not reach sta~slk~alsignificance(p=ns). The applicationof aflenuationeoweclion. decreasedthe false positiverate from 25.4% (17/67)to 4.4% (3/87) for 14Cand AC studies raspec~ely. In conclusion,nonuniformattenuationwithin ~ chest heavily affected M-SPECT results in a pq0~lation at low risk for CAD. Correction for aUeouationarfifects effectivelyreducedthe numberof false positivestudies,~th a consequentimprovementof specificity.

11.3

11.5

i~EFT MAIN CORONARY DISEASE: INCREASED SENSITIVITY WITH QUANTITATIVE ATTENUATION CORRECTED SPECT PERFUSION IMAGING C. D u v e r n o y , E. Ficaro, M. K a r a b a j a k i a n , P. Rose, J. Corbett. U n i v e r s i t y of M i c h i g a n , A n n Arbor, MI, U.S.A.

LVEF CALCULATED FROM GATED THALLIUM (G TI) SPECT: COMPARISON WITIt Te-99m MUGASTUDIES, H.M, Abdet-Davem, M. N. Infantino', D.S. Acun~, S. Atay, J.Q, Luo, E.L Bemaski', H.H. AbujudehT,H. Etmquist'.S.Y. Naddaf, W.S. Omar, M. Kumar. Nucl Mad Sec,Dept Rad & Card See', Dept Med. St Vincent'sHosp & Mud Center of NY and NY Mud Coll, ValhallaN,Y.

T h e s e n s i t i v i t y o f S P E C T p e r f u s i o n i m a g i n g is g e n e r a l l y e x c e l l e n t for the d e t e c t i o n o f c o r o n a r y h e a r t disease. H o w e v e r , p r e s u m a b l y b e c a u s e of b a l a n c e d reductions in m y o c a r d i a l p e r f u s i o n , S P E C T has d e m o n s t r a t e d l i m i t e d s e n s i t i v i t y for the i d e n t i f i c a t i o n o f a pattern s p e c i f i c for left m a i n ( L M ) c o r o n a r y stenosis. B e c a u s e r e g i o n a l q u a n t i t a t i v e p e r f u s i o n b i a s e s are e l i m i n a t e d w i t h a t t e n u a t i o n c o r r e c t e d (AC) vs. u n c o r r e c t e d (UC) S P E C T , w e h y p o t h e s i z e d that A C SPECT should demonstrate increased diagnostic sensitivity for the d e t e c t i o n o f s i g n i f i c a n t L M c o r o n a r y s t e n o s e s . W e s t u d i e d 2 0 pts. (17 m e n , 13 p r i o r M I ) a g e 66+9 yrs w i t h s i g n i f i c a n t L M s t e n o s e s ( > 5 0 % stenosis). S i g n i f i c a n t coronary stenoses w e r e also p r e s e n t in 19 L A D , 13 L C x , and 17 R C A territories. S t r e s s T c - 9 9 m s e s t a m i b i S P E C T a n d A C w e r e p e r f o r m e d as w e h a v e p r e v i o u s l y described. Both A C and U C i m a g e s w e r e q u a n t i f i e d and c o m p a r e d to the a p p r o p r i a t e A C and U C n o r m a l d a t a b a s e s (_>2.5SD, 3-D M S P E C T ) . U C S P E C T i d e n t i f i e d 34 a n d A C 51 of the s t e n o s e d territories (p<0.001). T h e r e w e r e i n c r e a s e s in defect e x t e n t scores in the A C i m a g e s for all c o r o n a r y territories. A l a r g e c o n t i g u o u s area of r e d u c e d p e r f u s i o n e n c o m p a s s i n g > 2 0 % o f both the L A D and L C x t e r r i t o r i e s w a s c o n s i d e r e d s p e c i f i c for L M stenosis. W i t h A C S P E C T 14/20 pts. (70%) d e m o n s t r a t e d the L M pattern o f a b n o r m a l i t y w h e r e a s only 3 pts. (15%) did so with UC SPECT (p=0.001). Conclusion: Attenuation corrected S P E C T results in s i g n i f i c a n t l y i n c r e a s e d s e n s i t i v i t y for left m a i n c o r o n a r y stenoses.

Recent advances in multidetectorgamma cameras, acquisition and processing protocols have made multlgatedTI SPECT myocardialperfusfun (MP) imaging available and feasible for clinical practice. The purpose of this study was to correlate LVEF calculated(talc) t~'omG TI SPECT in both the early (E) and the delayed(D) imagingwith that talc from Tc-99m MUGA studies. 41 patients(29 M and 12 F) who were referred for stress TI MP imaging (treadmill (I 9) or pharmaco[stressing(17 adenosine. 5 dobutamine),age 39 to 89 years with mean age 61.7 years. All pts had IV injection 2.8-3.2 mCi of TI-201 at peak exerciseand imaged 15 rain and 3 hours later, dual head (ADAC, Vertex Epic at 90"), 16 projectionsper head for a total of 32 projections, 180",64 x 64 matrix, 60 secondsper projectionand 8 slicesper cardiaccycle. E and D summedimageswere processedand displayedfor evaluationof MP. Gatedstudieswere processedfor cale of LVEF accordingto manufacturers'protocol. All pts agreed for Te-99m MUGA study immediately following TI study using Tc-99m pertachnetate for invlvo labelledRBCs technique20 mCi, IV, MUGAstudies were processed for eatc of LVEF. 24 pts had history of at least 3 risk factors ~rbr1HD with abnormalMP studies, 21 had normalMP, 18 stressiuducedmyocardialischemiaaud 2 had myocardialscar. The calc LVEF ranged from 17-81% with a mean of 54.59% from the E gated SPECTand rangedfrom 21-81% with a mean of 54.88% from the D gated SPECT studies,From mugaLVEFrangedfrom 19-77%with a meanof 53,75%. Correlation ofcalc LVEFbetweenthe MUGA and the E gated SPECT was 0.8 with SD 13 and betweenthe MUGAand the delayedG SPECTwas 0.9 with SD 14.

LAD

92% (25/27)

97% (32/33)

67% (18/27)

100%(3,3/33)

RCA

87% (21/24)

92% (35/38)

91% (22/24)

53% (20/38)

We conclude:G TI SPECT is useful for LVEF ealc and correlateswith MUGA. This further promotesTI use for MP imaging.With currenttechnology,low dose and energyof Tl is not a limitationfor the G SPECT,

S18

Abstracts Monday morning, April 7, 1997

12.1 M O N D A Y A M A P R I L

PREDICTIVE"VALUE OF FDG iMAGING IN PATIENTS WITH CHRONIC ISCHAEMIC LEFT VENTRICULAR DYSFUNCTION ENROLLED IN A PROSPECTIVE EUROPEAN MULTICENTRt~ VIABILITYSTUDY EEC Concerted Action on Positron Emission Tomogaphy (PET) Investigationof CellularRegenerationand Degeneration[London(UK) Louvain (B), Lyon (F), Groningen (NL), Liege (B), Turku (SF) Copenhagen(D),Aachen(G)] Aim of this study was to ascertain the value of quantitativePET witl7 18F-fluorodeoxyglucose(FDG) to identityhibernatingmyocardium.A total of 502 patients (pts) with at least one dysfunctional(D) segmenl (S) subtended by a stenotic coronary artery amenable tc revascularization(R) were enrolledover 2 years. Left ventricular(LV) functionwas assessed before and 4-6 months after R by radionuclide ventriculographyor echocardiography. To maximisemyocardial FDG uptake and overcome insulin resistance, all studies were performed during euglycemichyperinsulinemicclamp (EHC). A total of 254 pts have undergoneR, by angioplasty(14%) or bypass.Completefollow up data on 121 pts (age 59-+9) who had R are available: LV ejection fraction (EF) was 37-+13%before and 40-+15%after R (p<0.01); the regional wall motion score (l=normal; 2=hypokinetic; 3=akinetic; 4=dyskinetic)was 2.0_+0.6before and 1.7+0.6after R (p<0.001). A total of 326 S were normal(N) and 382 D. AfterR, 204 (53%) D-S improved (IMP), 149 (39%) were unchanged(UNC)and 29 (8%) worsened. The Metabolic Rate of Glucose(MRG;lamol/mirdg;lumpconstant=1) was 0.42_+0.18in N-S, 0.38_+0.17in IMP-S (p<0.01 vs N) and 0.31+0.17 in UNC-S (p<0.01 vs N and IMP). In conclusion.,these interim results indicate that FDG-PET during EHC can provide the quantitative assessment of myocardial viability in the absence of perfusion measurement.

Journal of Nuclear Cardiology January/February 1997, Part 2

12.3 COMPARISON OF STUNNED AND HIBERNATING MYOCARDIUM: TIME-COURSE OF FUNCTIONAL RECOVERY. F. Haas, N. Augustin, C. Haehnel, C. Duvernoy, S. Nekolla, W. Picker, H. Meisner, M. Schwaiger. German Heart Center Munich, Germany It has been demonstrated that NH3/FDG-PET predicts the mnctional recovery of ischemically comprofifised my9cardium. This study evaluated the time-course and the extent of irgprovement of %ibernatin~ mTocardium" (flow-metabolfsm-mismatch; HIB) and- of" "stunned myocardiun:" (normal flow/metabolism but impaired tunction; STU). 26 patients with CAD and CI-IF (EF=27%) were functionally assessed by. 2-d echocardiography_ using a 5-point grading system ~rom -1 (dyskinesia) to 3 (normal) preoperatively, 10 days, 4 month and one year after CABG. 213 revascularized freewall LV-segments with wall motion abnormalities were examined: 2-8% of the segments displayed HIB, while the remaining 72% STU. While after ten days only 50% of HIB segments showed functional recovery, at tour montias and one year after CABG 73% and 87%, respectively, displayed recovery. In contrast, 77% of STU segments regained normal to near normal function after 10 days (p=0.005), after 4 month 85°/..o (p=0.01) and after I year 85%. The results suggest that in patients with CHF scinfigraphic patterns of "stunning" are more prevalent than that o f qfibernation". Stunning predicts early recovery after revascularization; whereas, HIB was associated with more severe baseline wail motion abnormalities and delayed functional recovery_, suggesting slow repair processes with ventrieular remodeling.

12.2

"12.4

"HYBERNATING" MYOCARD1UM REQUIRES EARLY REVASCULARIZATION TO PREVENT IRREVERSIBLE CELLULAR DAMAGE J. yore Dahl, E.R. Sehwarz, J. Schaper, N. Schmiedtke, G. Schulz, F. Schrndube, U. BfiI1, P. Hanrath University of Aachen Hospital, Aachen, Germany "Hibernating" myocardium is characterized by a varying degree of ultrastractural cellular changes leading to degeneration. To evaluate the time-course of this phenomenon, we correlated morphologic findings in myocardial biopsies obtained during CABG from 26 patients (pts) with a perfusion]metabolism "mismatch" with the extent of postoperative functional recovery, assessed from 6 month follow-up angiography (f-u-a), and the time interval between diagnosis of "hibernation" and CABG. Electron microscopy revealed different degrees of tissue degeneration with loss of contractile material, cellular sequestration and fibrosis. Neither the preoperative nuclear findings nor the ultrastructural changes predicted the extent of functional recovery. However, pts (n=10) undergoing CABG _<30days following baseline imaging demonstrated a significant better recovery (EF increased from 49_+9 to 58+12%, p<0,05) at fu-a and less replacement fibrosis compared to 16 pts with a longer interval between diagnosis and CABG (EF 40-!-_11% and 45+11% resp., p<0,05). These findings indicate that "hibernation" may represent a rather unstable and transient condition, in which a progressive structural degeneration occurs accompanied by a decreasing degree of functional recovery following revascularizafion.

D~ECTING THERAPY 1N PATIENTS WITH SEVERE VENTRICULAR DYSFUNCTION USING FDG PET R.S.Beanlands, R.A.deKemp, S. Smith, M.Aung, B.Aubrey, R.A.Davies. T.D.Ruddy,Ottawa Heart Institute, Ottawa, Canada In patients(pts) already selected for revascularization (REV), FDG PET predicts wall motion recovery. However, its effect on selecting pts for REV is not clear. FDG PET images were reviewed with rest perfusion SPECT images to define viable myocardium or scar in 140 pts with CAD; 85 patients were identified with EF<35%. Attending physicians answered a questionnaire on intended management(IntMx) before and after PET to determine how it influenced decisions: Post PET Intended Mana.gement: Pre PET Intended Management: Med REV Tx Unc Medical (Med)(n= 14) 7 7 0 0 Revascularization(REV) (n=33 ) 14 19 0 0 Transplant work-up(Tx)(n=15) 0 8 7 0 Uncertain (UNC)(n=23) 8 12 2 1 PET had important impact on decision making indicated by the poor agreement between Prevs Post IntMx (kappa=0.23 (after UNC cases excluded)). In 46 pts referred for REV after PET, 4 died awaiting surgery; 34 have had 3 months followup: post REV(n=18), EF improved (24:t:6 to 28±8%(p<0.05)). In 16 pts still awaiting REV, EF did not change (284-5 to 28±5%(p=NS)). FDG PET can direct difficult therapy decisions for patients with CAD and severe LV dysfunction and identifies patients at high risk for early cardiac events while awaiting REV:

Journal of Nuclear Cardiology Volume 4, Number l, Part 2

Abstracts Monday morning, April 7, 1997

SI9

12.5

13.2

VALUE OF REST/REDISTRIBUTION TL-201 SPECT,TC-99 MIBI-GATED SPECT,DOBUTAMINE ECHOCARDZOGRAPHY AND 18-FDG PET IN PATIENTS WITH ISCHEMIC MYOCARDtOPATHY: PRE AND POSTREVASCULARIZATION STUDY.

RELATIVE MYOCARDL~L PERFUSION RESERVE IN HYPERTENSIVE PATIENTS. M.J. Garcia Velloso, A. Huelmos*, A. Cabrera, J.M. Marti, D. Martinez-Caro*, J.A. Richter. Deps of Nuclear Medicine and Cardiology*. University Hospital ofNavarra. Pamplona. Spain,

M.Hernandez, V . P e r a l , I . V i l a c o s t a , E.Merofio, HJ Perez Castejdn, R.Montz, J . D e l Olmo, L.SanchezHarguindey, JL Carreras. San Carlos Univ. H o s p i t a l . Madrid. Spain. The aim o f t h i s study was t o assess t h e diagnost i c value o f T1-201 SPECT,dobutamine e c h o c a r d i o graphy (DE) and 18-FDG PET i n areas o f myocardium w i t h depressed but r e v e r s i b l e c o n t r a c t i l e function.16 patients with ventricular disfunct i o n underwent,on separate d a y s , r e s t / r e d i s t r i b u t i o n T1-201 SPECT,DE,MIBI-GATED SPECT,18-FDG PET and coronary angiography.One month a f t e r revascul a r i z a t i o n the same p r o t o c o l was r e p e a t e d except PET.The e v a l u a t i o n was made on 80 severe h y p o k i n e t i c and hypoperfused but v i a b l e segments. The r e s u l t s o b t a i n e d are the f o l l o w i n g : DE TL-201 PET S e n s i t i v i t y (S) 76% 74% 70% S p e c i f i c i t y (E) 59% 58% 92% Pos.Pred.Value (PPV) 67% 63% 88% Neg.Pred.Value (NPV) 74% 63% 74% In c o n c l u s i o n , t h e E and PPV o f PET are h i g h e r than the o t h e r techniques t o p r e d i c t f u n c t i o n a l recovery.

The purpose of this study was to evaluate the myocardial perfusion reserve (MPR) in non-treated patients with arterial hypertension (HT) and left ventricular hypertrophy (LVH). Thallmm-20I SPECT at rest and after adenosine-tfiphosphate (ATP) was performed in 14 patients and 11 control subjects. MPR indexes were calculated as the ratio between corrected stress and rest peffasion values. The coronary" angiography performed in 6 patients was normal. Age, echocardiographie data and regional MPR indices &the vascular territories were: *p<0.05**p<0.01 Controls HT Patients Age 48.4 _+9 54.7 _+8.3 LVM 98.1"+_ 27.4 i72.2 _+40.4** E/A 1.17 _+0.2 0.93 +_0.3" MPR-LAD 1.86 + 0.10 1.48 + 0.19'* MPR-LCX 1.80 + 0.12 1.42 ± 0.17'* MPR-RCA 1.80 ± 0.10 1.44 + 0.16** Conclusion: The reduction of the MPR indices was highly significant in this patients. PrimaD' alterations at the level of microcirculation could be responsible for the reduction of the myocardial pcrfusion reserve in this patients.

13.1

13.3

ISOPROTERENOL (ISP) STRESS BMIPP MYOCARDIAL SPECT IN PATIENTS WITH CORONARY ARTERY DISEASE OR SYNDROME X. S.Watanabe, R.Ajisaka, K.Eda, N.Takeyasu, H.Kamiya, T.tshimrtsu, T.Takeda, Y.Sugishita. University of Tsukuba, Tsukuba, Japan.

THALLIUM-201 SPET IN MYOCARDIAL BRIDGING OF THE LEFT ANTERIOR DESCENDING CORONARY ARTERY. M.Cavaggioni, P.Braggio, PG.Giorgetti, *R.Albiero, *A.Variola.

We investigated the ability of ISP stress BMIPP myocardial SPECT (ISP-BM) to detect metabolic abnormalities in patients (pts) with coronary artery disease (CAD) or syndrome X (SX). Nine pts with CAD (age 63_+8) and 10 pts with SX (age 55+_15) underwent ISP-BM, resting BMIPP SPECT(rest-BM), ISP stress thallium SPECT(ISP-TI) and ISP stress echocardiography (ISPecho). To evaluate the myocardial uptake of BM or TI, the left ventricle was divided into 13 segments. In pts with CAD, 31 of the total of 35 segments in which ISP-TI demonstrated redistribution (RD) had reduced uptake of BM even in rest-BM. ISP stress decreased BM uptake in only 5 segments and increased it in 13 segments. In 22 of the 35 segments with RD in ISP-TI, wall motion deteriorated in ISP-echo despite no change or even an increase in BM uptake. In pts with SX, 9 segments showed RD in ISP-TI and 15 other segments showed an ISP-induced decrease in BM uptake. All but 1 of the latter segments showed no abnormality in ISP-TI. Only I patient showed wall motion abnormality in ISP-echo in the area with an ISP-induced decrease in BM uptake. Conclusion: In pts with CAD, ISP-BM provides less information about myocardial ischemia, but in pts with SX, this technique can detect metabolic abnormalities sensitively in those segments in which neither perfusion tracer nor stress echo can detect them.

Servizio di Medicine Nucleare e *Servizio di Cardiologia. Ospedale Civile Maggiore. Azienda Osp. di Verona. Italy. Myocardial bridging (MB) of the left anterior descending coronary artery (LAD), identified by an angiographic systolic narrowing, has been reported to occasionally cause reversible myocardial ischemia (Mi) by exercise planar Thallium-201 scintigraphy. SPET might improve detection of Mi in patients (pts) with MB. To test this hypothesis 14 consecutive pts with ME] ol the LAD without angiographic atherosclerotic lesions in the LAD were retrospectively evaluated. Seven pts (50%) had normal coronary arteries; the remainders had either a single (5 pts) or double (2 pts) vessel disease of the right or/and left circumflex coronary arteries. After cycle ergometer test SPET TI-201 scintigraphy was performed with a semiquantitative interpretation of the images in the LAD territory. In 6 pts no perfusion defects were found. A reversible pertusion defect was detected in 8 pts (57%): mild and limited to the medium~listal anterior septum in 7, moderate and involving the anterior septum and a portion of the apex in 1, the only one with a systolic diameter reduction >80% associated with a length >30 mm of the bridged segment by angiography. Conclusion: In pts with MB of LAD a reversible perfusion defect by SPET TI-201 scintigraphy was a common finding, which was mostly mild and localized to the medium-distal anterior septum, possibly as a consequence of reduced perfusion in the septal branches arising from the bridged segment.

M O N D A Y A M A P R I

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Abstracts Monday morning, April 7, 1997

13.4 M O N D A Y A M A P R I L 7

IS THERE A DIAGNOSTIC ROLE FOR EXERCISE-INDUCED ST SEGMENT DEPRESSION (ST-[.) IN PATIENTS WITH PREEXISTING RIGHT BUNDLE BRANCH BLOCK (RBBB)? A.R. Galassi, C. Mammaua, R. Grassi, R. Foti, G. Russo, G. Lieciardello, G. Giuffrida, Institute of Cardiology, University of Catania, Italy. The significance of ST,[, iu patients (pt~) with RBBB has been meagrely reported in the literature. The clinical studies reported have produced disparate results regarding sensitivity and specificity in the detection of coronary artery disease. To this end, 18 consecutive pts (mean age 64_+7 years) with RBBB uudcrwent 99mTc-TetrofosminSPECT exercise scintigraphy as a diagnostic work-up. Patients with Q-wave myocardial infarction, valvular disease, left ventricular hypertrophy and coronary artery by-pass graft were excluded. Symplom-limiled exercise testing were performed off treatment, and the number and dislribution of stress-induced reversible perfusion defects assesscd by 99mTc-Tetrofosmin-SPECT. All pts underwent maximal exercise test, Rate-pressure p,'oduct mid time at peak exercise were (24102_+2817 mmHgxbpm mid 17+2 rain, respectively). Ten pts (55%) showed _>1 mm ST,I, in leads VI-V6, 4 pts (22%) in leads VIV4, m~d I patient (5%) in leads V5-V6; in 3 pts (17%) _>1 mm ST.I. was not detected. With stress-induced reversihle 99mTc-Tetrofosmin perfusion defects used as end poinl for myocardial ischemia, _>1 mm ST,[, occuning ia leads V1-V4 gave a sensitivity of 85%, a specificity of 50% and a predictive accuracy of 77%, while when it occurred in leads V5-V6 gave a sensitivily of 71%, a specificity of 75% and a predictive accuracy of 77%. These data indicate that in a patient population refen'ed for treadmill testing, exercise-induced ST,bin the preseuce of RBBB may be appropriate for evalualing myocardial ischeruia as assessed by scintigraphy. The specificity of exercise tesling appem's to be grealer if STJ, is recorded in leads V5-V6.

Journal of Nuclear Cardiology January/February 1997, Part 2

14.1 REDISTR1B['YIONOF BIS (N-ETHOXY, N-ETHYt. DITHIOC.~RB.-M\IATO) NITRIDO TECHNETIUM-99M-(V). A NEW MYOC.M~DIAL PERFUSION IMAGING AGENT : COMPARISON WITH 20t "I'HAIE~RJM REDISTRIBUTION. C. Ghezzi, D. Faget, P.Y. Bricbon, J.P. Mathien, R. Bontron, R. Pasqualini, J. de Leiris, M. Comet. University, Grenoble, France. Bis (N-ethoxy, N-ethyl dithiecarbmnato) nitrido 99mTc (TcN-NOET), is a neutral lipophilic myocardial perfusian imaging agent, which has beeu show~l to undergo apparem redistribution in animal models and in man. This study evaluates the early and late myocardial distribntions of TcNNOET and 201 Thallimn under conditions of low-flov," ischenfia, to determine whether TcN-NOET exhibits a rest redistribution, comparable to that of 201 Thallium. I~hemia was induced in t0 anesthetized° openchest dogs by partial occlusion of the left. ant~ior descending coronaO, artery. Two different protocols (live dogs in each) have been performed. In each protocol, dogs were injected intravenously with TcN-NOET, 201 Thallium, and radiolabeled microsphems after 30 minutes of low-flow ischemia. In protocol 1, the hearts were excised 20 ~niuntes after the injection of the tracers, and in protocol 2, after 150 minutes, ischemia being maintained dttring the entire experiment. Myocardial activities of TcN-NOET and 201 Thallium were detemth~ed ~ in vitro counting, and correlated ~s~[thmdiolabeled mierospheres activity.The early myocardial distrilmtions o1"TcN-NOET and 201 Thallium were comparable and a h i l l y significant linear oorrelation was noted between TcN-NOET, 201 Thallitun and normalized Nood flow (r--0.95 and r=0.97, respectively). However, TcN-NOET and 20I Thallinm tended to overestimate flow in the low-flow range and to underestimate flow in the high-flow range (protocol I).A significant difference was observed in myocardial 201 Thallium (p<0.01) and TcN-NOET (p<0.01) activities between the two groups of dogs (early and Iat¢ distribution), demonstrating a decrease in the activity of both tracers in the high-flow range and an increa~ in their activi~ in the low-flow range.The nornmlized activities office two tracers were identicals in this study, clearly demonstrating that TcN-NOET redistribution is conxparable to that of 201 Thallimn.

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14.2

Endothelial Dysfunction Assessed by Intracoronary Aeetylehollne and Tc99m-Sestamlbi Myocardial Pertusion Images. Osval do Masoli, Nestor Perez Batifio, Ana Di Leva, Oscar Carlevam, Diego

IN VITRO UPTAKE KINETICS OF BIS (N-ETHOXY, N-ETHYL DITHIOC.~RB.~MATO)NITRIDOTECHNETIL'M-99M(V), A MYOCARDIAL PERFUSIONIMAGINGAGENT: A STLrDYIN CULTUREDCARDL&CCELLS. C. Ghezzi, D. Fagret, L. Rioo, O Mouton, J.P. Mathien, R. Pasqualini, J. de Leiris, M. Comet. Uinversity, Grenoble, France. Bis (N-ethoxy, N-ethyl dithiucarbamato) nitrido 99mTc (TcN-NOET), is a nentral lipoplfilic myocardial perfusion imaging agent, which has been shorn1 to undergo apparent redistribution in an/anal models and iu mml. Its binding clmractefistics were evaluated in cultures of beating myocardial cells of newborn rots. The uptake and release kinetics of the tracer were examined. Myoc}¢es showed uptake of TcN-NOE'I" to a plateau level x~itha half-time 01/2) of 11,5 ± 0.7 mitt (n=6); tl/2 appear to be independant of extracellular TcN-NOET concentration (range: 10 pM to 0.1 nM). During the washing phase, no appreciable activity, was lost by the cells. Metabolic inhibitian induced by pre-incubafion of cells for 5 nfinutes or 60 minutes with Rotunone (5-50 raM) or Iodoacetic acid (0.1-1 n~M) had no effect on the l-rain or 30-rain TcN-NOET uptake. Preineubation of cells for 5 minutes with Cyanide (5 raM) increased lrain and 30-rain TcN-NOET uptake to 1-45 4- 11% (p<0.01) and 185 ± 23% (p<0.01) of control respectively (n=6). These conditions of metabolic inhibition were not associated with lactate dehydroganase relent, suggesting that TeN-NOET uptake can not be due, under these experimental conditions, to membrane disruption. Effect of membrane transport inhibitors on l-mitt TcN-NOET uptake was also studied. Cells were preincubated in solutions containing inhibitors for 15 minutes prior to detemtinatian of tracer uptake in the presence of inhibitors. Amiloride (100 nLM), Ouabaine (100 raM) and Bumetainde (10 raM) had no effect on the TcN-NOET uptake. Calcium blockers, Vorapamil (1 raM) and Diltiazenl (10 raM) reduced significantly the uptake of the tracer, being 67 ± 11% (p<0.01) and 65 ± 14% (p<0.01) of the control value respectively (n=6). On the other hand, a calcium channel activator (BayK 8644 - 0.25 raM) increased this uptake to 171 =t= 12% (p<8.01) of the control value. These results snggest that TeN-NOET uptake might be, at least in part, mediated throught an interaction with calcium channels.

Sabat,~, 3orge Jalbn, Alejandro Meretta, Daniel Cragnolino, Ricardo Sarmiento, Alberto Ramps. Hospital Cosme Argedch, Buenos Aires, ARGENTINA. The coronary vasomotor response to acetyleholine (AGH) intraceronary infusion and their correlation with Te-£gm-Sestamibi (MIBI) myocardial Perfus}on images was assessed. We prospectively enrolled 9 patients (7 males) without previous myocardial infarction and £6 hours withdrawal of antisehemic medication. Mean age 46.7 years (range: 37-60), mean serum cholestsmt levels 272 _+91 mg%, 6 patients (66%) had smoking history, 5 (55%) had history of hypertension, 6 had stable angina, 2 recent onset typical angina and I siront Nchemia,Baseline angiogrsphy was performed and arteries were classified as Abnormal: with > 10 % of etenosis or Normal: without angiographicaly significant stenosis (< 10 %).Then ACH was infused at concentrations 50 and I(30 p.g into the left main (LAD and LCx territories), if there were not response 25 to ,~0 t~g were infused into RCA. Inmediate angiography was performed after each dose. A positive response to ACH was considered when vasoconstriction (VC) was 20 % narrowing of the lumen diameter, assessed by digital-based quantitative coronary angiogrsphy. At ACH peak dose, 20 mCi MIBI were inyected i.v. Sixty minutes later planar images in anterior, LeA 45 and lateral views were aquited (ACH images). Next day, 20 mCi MIBI were inyected and another set of images were obtained (Basal images). The image sets were classified as "Abnormal" ( hipoperfused -HP-) or "Normal ", based on the presence or absence of any kind of perfusion defect. In the 9 LAD artedes: 5 abnormal, in which 4 (80%) presented VC with ACH and hipoperfusion (HP) with MIBI and the others 4 were normal, 1 (25%) presented VC and liP. In the 9 LOx: 3 abnormal, in which 2 (66%) presented VC and liP and in the 6 normal arteries, 2 (33%) presented VC and HP. In the 9 RCA: t abnormal, with VC and HP and 8 normal without MC and HP. There were 100 % correlation between the VC artery and HP territory. In the 17 artedes without VC there is not territory with liP. The ACH failed to create an ischemie response by either VC or HP in some patients. Conclusion: These preliminary results indicate that Tc-£6m-Sestamibi myocardial perfusion imagen identified coronary artery territories with an abnormal response to ACH as determined by VC. This approach could prove to be important in ident[~ng patients with endothelial dysfunction and coronaries with less than 50 % lumen narrowing.

Journal of Nuclear Cardiology Volume 4, Number I, Part 2

Abstracts Monday morning, April 7, 1997

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14.3

14.5

MYOCARDIAL UPTAKE OF 99TC-NOET IN DOGS WITH REPERFUSED ACUTE MYOCARDIAL INFARCTION: COMPARISON TO TL-201 G. Vanzetto, DA.Calnon, M. Ruiz, DD. Watson, GA. Beller, DK. GIover. University of Virginia, Charlottesville, USA NOET is a new neutral lipophilic myocardial perfusion agent that redistributes in canine models of short term hibernation. We sought to determine the ability of NOET to assess viability in acutely infarcted reperfused myocardium. Accordingly, T1 and NOET were co-injected in 6 dogs after 1 hr of reperfusion (Rep) following 3 hrs of total LAD occlusion (Occ). Serial NOET images were acquired for 2 hrs. Regional myocardial blood flow (MBF) and Tl and NOET activities were determined by gamma-welt counting. Infarct size averaged 39+7% of the risk area by TTC staining, Mean infarct-to-normal MBF ratio was 0.13+_0.04 during Occ, and 0.93+_0.23 after Rep. Infarct-to-normal T1 activity ratio was 0.32+0.07 reflecting the extent of the necrosis. In contrast, NOET activity ratio was 0.74_+0.12 (p<0.01 vs TI), more reflective of Rep flow. Similarly, the LAD/LCX count ratios on NOET images were 0.71+_0.10 and 0.82__.0.I2 at 5 and 120 min after injection. Thus, in the setting of acutely infarcted, Rep myocardium, NOET uptake is a good marker of Rep flow, whereas TI uptake appears to be a better marker of viability.

KINETICS OF 1, 3, 4, 6-TETRA-ACETYL-2-[F-18]-2-DEOXY-DGLUCOSE (A-FDG) IN THE ISOLATED RAT HEART. N. Nguyen, M. Herz, S. Egert, S. Ziegler, G. St6cklin, M. Schwaiger. Technische Universit&tM0nchen, Germany. It has been suggested that the glucose transporter dependent cellular uptake of FDG is rate-limiting in exogenous glucose utilization in the heart. Thus, the purpose of this study was t o evaluate the kinetics of A-FDG, which in £ontrast to FDG is taken up independentlyof transport. However, it is hydrolyzed and phosphorylated within the cells similarly to FDG. Hearts were perfused according to Langendorff with Krebs-Hensleit bicarbonate buffer containing A-FDG andl0mM glucose. After baseline measurements, insulin was added. Rate of tracer accumulation (ml/g/min) was calculated. At baseline, A-FDG accumulated (0.16_+0.01) approximately 7 times faster than FDG (0.02±0.01)in the same model. After insulin, there was an initial clearance of A-FDG (-0.029+0.001) in contrast to FDG, which showed an approximately 6-fold increase in uptake compared to baseline (0.11±0.06). Approximately 10 minutes after insulin, however, A-FDG was again taken up at a reduced rate (0.02+0.01). Thus, the faster accumulation of A-FDG compared to FDG provides further evidence that transport is rate-limiting for glucose utilization at baseline. The initial clearance of A-FDG after insulin suggests that the increase in glucose transport stimulated by insulin increases cellular glucose concentration, which competes with FDG for hexokinase activity, causing a net efflux of the tracer. After approximately 10 minutes, glucose transport again appears to be rate-limiting; hence, the positive myocardial accumulation of A-FDG. The presented dual tracer technique may provide new insights into the roles of transport and phosphorylation in the regulation of exogenous glucose utilization.

14.4

15.1

BMS-194796 UPTAKE IN A SWINE MODEL OF

NITROGLYCERINE ENHANCED Tc-gPm SESTAMIBI IS COMPARABLE TO TI-201 FOR THE DETECTION OF VIABLE MYOCARDIUM IN CONGESTIVE HEART FAILURE R. Senior, S. Kaul, U. Raval, A. Lahiri. Deparmlentof Cardiology, Northwick Park Hospital, Harrow, UK.

DEMAND ISCHEMIA.

Lynne L. Johnson, Lorraine Schofieid, Patricia Mastrofrancesco, Tammy Donahay. Rhode Island Hospital, Brown University, Providence, RI. USA To evaluate the uptake of Tc-99m labeled nitroheterocycle BMS 194796 in a demand myocardial ischemia model 8 swine underwent the following experimental protocol: 1) catheter placement of stenosis into the LAD, 2) baseline blood flow (BF) measurement (microspheres) and anterior interventricular vein (AIV) lactate sampling, 3) rapid atrial pacing x 4-6 mins, pacing BF measurement, AIV sampling, followed by i.v. injection of BMS-194796, 5) serial planar imaging x 2 hrs followed by SPECT imaging in the last 3 animals, 6) recovery BF measurement, 7) sacrifice, heart sliced, TTC stained and imaged on detector. None of the animals had infarcts in risk region (RR) by TIC. HR % lactate endo endo extraction BF RR BF nl control 104+21 6.2+23.2 0.85+.4 1.73+.3 pacing 191+14 -64.2+53.7 0.33+.3 1.37+.6 recovery 113+13 0.68+.2 1.62+.6 Positive scans: 1/8 planar, 3/4 SPECT, 8/8 ex-vivo. Cts in the RR/normal = 2.29-2_1.8 and the uptake of BMS in the RR = 0.25+0.10% of injected dose. Blood pool clearance was biexponential; early T 1/2 = 1.0, late = 62.2 mins. These data suggest that in this model, BMS-194796 is taken up in RR but that due to high background activity SPECT imaging is necessary.

Tc-99m sestamibi imaging (MIBI) is widely used to assess coronary artery disease (CAD) but its value for the detection of myocardial viability remains controversial. We prospectively evaluated 52 consecutive patients with congestive heart failure(CHF) (NYHA II-IV) due to CAD with LVEF_< 35%. Both T1-201 and MIBI SPECT imagingwere performed at rest following 0.5rag of sublingual nitroglycerine (NTG). Systolic wall thickening was assessed by echocardiography. Tracer uptake was scored semiquantitatively(0 = nomaal; 4 = absent) and viability was present when 50% tracer uptake was in a severely dysfunctional segment. The mean tracer uptake was also calculated in the dysfunctional segments using the semiquantitativescore for both MIBI and T1-201. Of a total of 624 segments (12 segment model) 459 (74%) showed severe dysfunction; of these, MIBI showed viability in 318(65%) and TI-201 in 298(61%) segments (p=NS). Concordance between TI-201 and MIBI was 81% (kappa = 0.60). The mean score of TI-201 and MIB1 were 1.89+0.74 and 1.99+0.66 (p=NS). Thus, NTG M1BI is comparable to T1-201 for the detection of viability in severelydysfunctional,nyocardium.

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A M A P R I L 7

Abstracts Monday morning, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

15.2

15.4

THALLIUM-201 UPTAKE AND FUNCTIONAL R E C O V E R Y A F T E R R E V A S C U L A R I Z A T I O N IN DYSFUNCTIONING VIABLE MYOCARDIUM. Livia Ruffini, Gian Battista Danzi, Guglielma R~ Ciliberto, Franco Spinelli, Oberdan Parodi. CNR Clinical Physiology Institute, Section of Milan, Niguarda Hospital, Milan, Italy

IMAGE QUALITY OF FDG NICOTINIC ACID DERIVATIVE.

SPECT

USING

A

Jeroen J Bax, Margreet A Veening*. Frans C Visser*, Arthur van Lingen*, Cees A Visser*. Leiden, *Amsterdam, The Netherlands.

The ability of SPECT Thallium-201 (T1) rest-redistribution to detect functional normalization of dysfunctioning but viable segments supplied by LAD coronary. ,artery is not yet c l a r i f i e d . W e studted 21 pts (17 men and 4 women) with hibernation of the LAD territory undergoing coronary revascularization. Viability (segmental activity >50% of the maximum) was observed in all pts (51/68 dysfunctioning segments). Among viable segments, 37 (72%) normalized their function after revascularization, with T1 uptake significantly higher than in segments without recovery (78+13%, 67+12% respectively, p < 0 . 0 1 ) . By logistic regression, a T1 cut-off value of 70%provided% the highest positive predictive value (88%)for complete functtonal recovery after revascularization in viable segments, with an overall accuracy of 76%. Despite similar rate of recovery among akinetic (19/25) and hypokinetic (18/26) viable segments, a significant difference in T1 uptake was observed (74+12%, 84+12% respectively, p<0.02). In conclusion, dysfunctioning viable regions supplied by stenotic LAD which normalize function after revaseularization show higher TI content than those without functional recovery. Viable hypokinetic.and akinetic segments show comparable functional improvement, despite different T1 uptake suggesting .-anunderestimation of true tracer concentration in akinetic regions, likely due to the partial volume effect.

Myocardial ~SF-fluorodeoxyglucose (FDG) uptake depends heavily on the metabolic conditions. Several approaches have been advocated to enhance myocardial FDG uptake, including oral glucose loading, hyperinsulinemic glucose clamping and administration of a nicotinic acid derivative (Acipimox). The current study aimed to compare the image quality of cardiac FDG studies using these different protocols. Eight patients tmderwent 3 FDG SPECT studies, on 3 different occasions, within 2 weeks. The image quality was expressed as the myocardial to blood pool (M/B) activity ratio. Plasma FDG clearance rates were also assessed. M/B ratios were similar after clamping and Acipimox (2.8+0.8 versus 2.9+0.7, NS) whereas the M/B ratio was lower after oral glucose loading (2.2+0.3, P<0.05 vs clamp and Acipimox). The FDG clearance was significantly slower after oral glucose loading (TK, oral loading=16.2_+5.7 min) as compared to clamping (T~A clamp=8.1_+3.1 rain) and Acipimox (TV,. Aeipimox=10.7+4.0 rain, NS versus clamp, P<0.05 versus oral loading). Conclusion: Acipimox administration and clamping yield comparable image quality and clearance rates; both methods yielded superior nnage quality and faster clearance rates as compared to oral glucose loading. Acipimox administration may be preferred in the clinical setting, since this technique is less laborious as compared to clamping.

15.3

15.5

GATED Tc-99m-TETROFOSMIN SPECT IN THE IDENTIFICATION OF MYOCARDIAL HIBERNATION: COMPARISON WITH TI-201 SPECT AND CINE MRI M Gunning, C Anagnostopoulos, G Davies, CJ Knight, DJ Pennell, K Fox, J Pepper, SR Underwood. Royal Brompton Hospital, London, UK. We assessed the value of gated Tc-99m tetrofosmin SPECT in identifying myocardial hibernation, compared with TI-201 uptake coupled with cine MRI. Methods 15 patients with LVEF <35%, underwent rest Tc-99m tetrofosmin SPECT, rest TI-201 SPECT, and cine MRI prior to CABG. The Tc-99m tetrofosmin image acquisition was ECG gated and tomograms were reconstructed in 16 frame/cycle cine sequences. Cine MRI was repeated postoperatively. Images were visually scored for tracer uptake and contractile function using a 9 segment model of the LV. Results 55 of 94 asynergic segments improved function following CABG. Sensitivity SpecificityPos.Predictive Gated Tetrofosmin SPECT 61% 45% 68% Rest Tetrofosmin/cineMRI 58% 62% 68% Late rest TI-201/cineMRI 67% 56% 69% Contractile function could not be classified in 21 of 135 segments using gated SPECT due to inadequate tracer uptake. Conclusion Gated Tc-99m tetrofosmin SPECT may be used to replace cine MRI for assessment of LV function in the identification of myocardial hibernation.

DELAYED REVASCULARISATION AFTER ACUTE MYOCARDIAL INFARCTION: PREDICTION OF CONTRACTILITY IMPROVEMENT BY THALLIUM SPECT. J. Rosso, M. Scherrer, J.L. Monin, A. Castaigne, JL Dubois-Randd, P Gudret, M. Meignan. Henri Mondor Hospital, Crdteil, France. This study was undertaken in 40 patients with acute myocardial infarction (MI) to correlate myocardial viability assessed by 201TI SPECT to contractility recovery 3 months after revascularisation of the infarct related artery. Methods: Myocardial contractility was evaluated by echography two weeks after acute MI. Wall thickening was assessed visually into 16 segments and a global wall motion index (WMSI) was calculated as the mean of the score of the 16 segments. All patients underwent revascularisation and were reevaluated 3 months after. Stressredistribudon-reinjection 201TI SPECT was performed within 2 days of initial echographic evaluation. Myocardial activity was assessed visually in the same segments. Dysinergic segments were considered viable if the defect improved (1 score) on redistribution or reinjection images or if 20ITI uptake was moderately decreased on all images. Results: The number of segments classified as viable before revaseularisation was correlated either with the number of segments that improved their contractility (r = 0.754; p = 0.0001) and with the improvement in WMSI (r = 0.657; p = 0.000l). The improvement of WMSI associated with 5 or more viable segments was more than 20% and significantly higher than those a~sociated either with 0-2 or 3-4 viable segments In conclusions, the number of viable scintigraphic segments appears to be a good predictor of the extent of myocardial functionnal recovery 3 months after revascularisation of the infarct related artery. However, at least 5 viable segments are necessary to observe a significant improvement in global myocardial contractility.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Monday morning, April 7, 1997

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15.6

15.8

COMPARISON OF REINJECTION THALLIUM201 AND REST SESTAMIBI FOR PREDICTION OF REVERSIBLE REGIONAL LEFT VENTRICULAR DYSFUNCTION A.M. Grossman, D.D. Miller, J.E. Udelson, TuftsNew England Medical Center, Boston, Mass., USA

DIAGNOSTIC ACCURACY OF QUANTITATIVE ANALYSIS OF RADIONUCLIDE VENTRICULOGRAPHY DURING STEPWISE DOBUTAMINE INFUSION IN POST-INFARCTION PATIENTS. L.Ceriani, E.Verna*,C.Carella*, L.Giovanella, S.Repetto*, G.Roncari Nuclear Med. and *Cardiology Dpts - Regional Hospital- Varese - Italy Aim.The aim of this study was to assess Sensitivity (Sn), Specificity (Sp) and diagnostic accuracy (A) of different quantitative parameters obtained from radionuclide ventriculography (RNV) during stepwise Dobutamine (D) infusion in the detection of residual ischemia in pts with prior myocardial infarction (MI). Methods. D-RNV was performed within two weeks after MI in 30 pts. 15 pts (Group I) had angina and a positive ECG-exercise test and I5 pts (Group II) had no evidence of ischemia. Ejection fraction (EF) was measured at baseline and at either low (Ld) (5-10 "f/kg/min) or high dose (Hd) (30-40 7/kg/min) D infusion. The following parameters were analized: the EF value at HdD infusion (HdD-EF), the absolute increase in EF at HdD (A-EF) and the occurrence of "up and down" response (U/D) with increase in EF at Ld followed by a decrease at Hd. The limits of normal response for quantitative parameters were defined as the 95th percentile of the distribution observed in a reference group of 10 normal subjects (HDEF=80%; A-EF=+12.5%; absence of U/D). Results. Mean HdD-EF and A-EF were significantly lower in Group I than in Group I1: p<.001. The UID was observed in 10/15 pts of Group I and 2/15 pts of Group I1. Sn,Sp and A were respectively: 100%, 7% and 53% for HdD-EF, 80% ,80% and 80% for A-EF and 67%,87% and 77% for UID. The combination of A-EF and U/D pattern showed the highest A (87%) with Sn of 93% and Sp of 80%. Conclusions: Quantitative analysis of early D-RNV is of value in the detection of residual ischemia in pts with recent MI. Best A is provided from the assessment of both &-EF and the pattern of EF response during stepwise infusion of the drug.

We studied 15 pts with CAD and LV dysfunction (EF 33+8%) to compare stress-redistributionreinjection (Reinj) thallium (TL) data and l-hour post-rest injection MIBI using SPECT. Quantitative analysis of tracer activities in 8 segments (segs) per pt was performed. RVGs were performed before (n=15) and after revascularization ( n = l l , 9 CABG, 2 PTCA) with scoring of regional function in 8 segs corresponding to the SPECT data. Among all dysfunctional segs, MIBI activity was similar to Reinj TL activity (70+15% [of peak] vs 70+15%, p=NS). Individual seg activities of Reinj TL and MIBI were correlated (r=0.80, p=0.01). MIBI and Reinj TL activities were similar among 26 segs with reversible dysfunction (75+13% vs 7 8 + 1 2 % , p=NS) and among 29 segs with irreversible dysfunction (65+17% vs 67+17%, p=NS). Positive and negative predictive values for functional recovery were similar. Hence, quantitative activities of Reinj TL and rest MIBI provide similar data regarding myocardial viability and the potential for functional recovery.

15.7

15.9

PREDICTION OF FUNCTIONAL RECOVERY AFTER REVASCULARIZATION BY PERFUSION/BMIPP IMAGING I. Matsunari, S. Fujino, J. Taki, J. Senma, T. Aoyama, T. Wakasugi, J. Hirai, T. Saga, S. Yamamoto, N. Tonami. Fukui Pref. Hosp.. Fukui, Japan

METOPROLOL IN DILATED C A R D I O M Y O P A T H Y Ian P. Clements, Wayne L. Miller, Mayo Clinic, Rochester, MN In order to analyze the clinical benefit of metoprolol, twelve patients with dilated cardiomyopathy received, in a double-blind randomized manner, treatment with either metoprolol (n=5) or placebo (n=7) for three months. Radionuclide ventriculography was obtained at rest and

We compared the efficacy of perfusion/BMIPP imaging in predicting functional recovery after revascularization to conventional TI imaging. 30 patients with coronary artery disease (mean LVEF 41+7%) underwent rest 99n~f'c-tetrofosminand I~3I-BMIPP imaging before revascularization as well as either stressredistribution-reinjection (n=28) or rest-redistribution (n=2) TI imaging. Left ventricular wall motion was assessed by gated blood pool scintigraphy. For perfusion/BMIPP imaging, a segment showing normal "mTc-tetrofosmin activity (>80% of~ak) or discordant BMIPP uptake at least 10% less than mTc_ tetrofosmin uptake was considered to be viable. For TI imaging, a threshold cutoff of 60% of peak on the final image (reinjection or delayed image after rest injection) was used as an index of viable myocardium. Functional recovery occurred in 58 of 122 (48%) dysfunctional segments. The predictive values for reversible dysfunction were as follows: Perfusion/BMIPP Thallium Positive Predictive Value 85%* 59% Negative Predictive Value 75% 84% Predictive Accuracy 79%* 66% *p<.05 vs thallium. Thus, perfusion/BMIPP imaging predicts functional recovery after revascularization even better than TI imaging.

mild exercise to measure left ventricular (LV) ejection fraction (EF), peak filling rate (PFR, end-diastolic volumes/sec) and time to PFR (TPFR, msec). (Table). PLACEBO METOPROLOL p

EF .17 .30 .03

REST PFR 1.89 1.80 .83

TPFR 178 211 .28

EF .19 .27 .11

EXERCISE PFR TPFR 1.89 127 1.48 168 .l0 .004

Metoprolol compared to placebo was associated with greater (p=0.02) cardiac cycle lengths at rest (921 + 292 vs 611 + 63 msec) and exercise (713 + 136 vs 510 + 117). LVEF was independently predicted at rest and mild exercise by cycle length (p=0.04 and p=0.05 respectively) but not by treatment (p=0.45 and p=0.96); TPFR at mild exercise was predicted by treatment (p=0.01) but not by cycle length (p=0.59). Thus, in dilated cardiornyopathy, metoprolol caused an increase in LVEF at rest and exercise associated with the chronotropic effect of metoprolol; prolongation of TPFR with exercise was independent of this effect. Metoprolol may have independent chronotropic and lusiotropic effects in dilated cardiomyopathy.

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Abstracts Monday afternoon, April 7, 1997

15.10 M O N D A Y P M A P R I L

CLINICAL VALUE OF INMUNOSCINTIGRAPHY WITH ANTIMYOSIN-Fab-DTPA-IIIIn ANTIBODIES IN THE DETECTION OF HEART TRANSPLANTATION REJECTION AND EVOLUTION RISK FACTORS. MLTabuenca, A.Lopez, M.Escribano, J. Ortia Berrocal. NUCLEAR MEDICINE DEPARTMENT. CLINICA PUERTA DE HIERRO. MADRID. SPAIN. OBJECTIVES: To evaluate the result of the application of antimyosineFab-DTPA-I I 1In Ab in 113 patients who underwent heart transplantation, and to determinate its diagnostic value in the detection of rejection, the factor s that modify the outcome, and the possibility of substitution of the endomyocardial biopsy by this procedure. MATERIAL AND METHODS: We obtained the normal values of 11 healthy controls. We performed 248 examinations in 113 pts. (11 pretransplantation), (235 in the interval from the 9th to the 1502 post-operative day) and (2 after the second transplantation). 41 pts. were studied in the 15post-operative day, (at the same time that the endomyocardial biopsy was performed), of whom, 22 presented rejection and 19 didn't. The number of examinations per patient ranges from 1 to 7. The ischemic period that the heart underwent was taken into account, as welt as the biosy result (ISHT classification) RESULTS: The statistical analysis using the ROC curves of the heart/lung uptake index, showed that with a cut value of 1.56, the procedure has a sensibility of 100% with a speeifity of 41%. The PPV was 77%, and the NPV of 100%, for rejection detection. There is no relationship between the uptake values and the days after transplantation, nor with the ischemic period. There is no correlation between the amount of uptake, and the histological grade (ISHT classification), whereas there is, between the degree of uptake and the existence of rejection in the first year postransplantation. CONCLUSIONS: The Antimyosine Ab can substitute the endomyocardial biopsy, wich should only performed if the Ab test is positive.

Journal of Nuclear Cardiology January/February 1997, Part 2

21.2 REDUCED CORONARY

CFR

WITHOUT STENOSIS

OVERT IN

HYPERLIPIDEMICS. I.Yokoyama, T.Ohtake, S.Momomura, M. Tateno, K. Yonekura, J. Nishikawa, Y.Sasaki, M.Omata. University of Tokyo, Japan. Reduced coronary flow reserve (CFR) in asymptomatic patients with hyperlipidemia was reported.To clarify whether coronary flow reserve can be reduced even in anatomically normal coronary arteries in hyperlipidemics, PET with 13NH3 was undertaken in 30 hyperlipidemics, and 11 age matched normal controls (9 males and 2 females). All patients were proven to have more than one normal coronary arteries within 3 major branches. Baseline myocardial blood flow (MBF) and MBF during dipyridamole loading (DP) in the areas perfused by angiographycally normal coronary arteries were measured with PET and then the CFR value was calculated. Baseline MBF in hyperlipidemics (75+_.27) was not different from that of controls (75+35). While, MBF during DP was significantly lower in hyperlipidemics (175+51.0) than that in controls (322+170, p<0.01). CFR was also significantly lower in hyperiipidemics (2.47_+0.76) than that in controls (4.2+1.4, p<0.01). CFR was significantly correlated with both plasma total cholesterol (r=.58) and LDL cholesterol concentration (r=.54). In conclusion, CFR could decrease even in anatomical normal coronary arteries in hyperlipidemics.

Monday PM, April 7, 1997

21.3

Sessions 21-26

PREVALENCE OF ABNORMAL MYOCARDIAL SPECT IMAGING IN DIABETICS W I T H NORMAL EPICARDIAL CORONARY ARTERIES Y America, D Groot, ZX He, JJ Mahmarian, MS Verani. Bayior College of Medicine, Houston, TX, USA

21.1 REASSESSING THE MEANING OF PERFUSION ABNORMALITIES IN PATIENTS WITH NORMAL CORONARY ARTERIES BY INTRAVASCULAR ULTRASOUND TECHNIQUES. E. Verna, L.Ceriani*, B.Castiglioni, S.Repetto,G.BinaghL Cardiology and Nucl. Medicine* Dpt, Regional Hospital, Varese, Italy Aim: Aim of the study was to assess the significance of scintigraphic myocardial perfusion abnormalffies in pts with normal coronary angiography. Methods: Intravascular ultrasound (IVUS) imaging and doppler fiowire velocity measurements (D)_were obtained at the time of angiography in 29 pts with suspected coronary artery disease (12 exercise angina, 7 rest angina, 8 prior non-Q myocardial infarction and 2 hypertrophic eardiomyopathy) who actually showed normal or near normal angiograms. Exercise or Dipyridamole SPECT images were normal in 10 pts (Group I) and abnormal in 19 (Group II). Presence and extension of occult atherosclerotic plaques (AP) or intimal thickening (IT) was assessed by IVUS of the proximal-mid segments of at least two major coronary arteries in each pt. The cross sectional luminal area (CSA) and area stenosis (AS%) were measured. Coronary flow velocity reserve (CFR) was assessed during Lc. Adenosine (A) induced hyperemia. Supine exercise induced changes in D flow velocity and IVUS CSA were assessed in 7 pts of Group II. Results: AP or IT were observed in 2/10 (20%) of Group I pts, and in 16/19 (84%) of Group II pts. Mean AS% was 46 _+ 10%. An abnormal vasodilatory capacity (CFR<2.5) was observed during A infusion in 1 pt of Group I and in 11/19 (58%) 10ts of Group II. An abnormal vasocostrictor response to exercise was seen in 5/7 (71%) Group II pts. Conclusions: Perfusion abnormalities as detected by SPECT images identify patients with functional and anatomical abnormalities of the coronary circulation despite normal angiography which may be recognized by IVUS and D studies.

Data are seamy regarding myocardial perfusion in diabetic patients (pts). Accordingly, we evaluated the prevalence of abnormal myocardial SPECT in such a population. Two hundred eleven consecutive diabetic pts (128 males, 83 females, mean age 63+10 years) who had stress (68 exercise, 143 pharmacologic) myocardial SPECT and coronary angiography were included. Pts with previous coronary revascularization were excluded. On coronary anglography, 40 pts had normal coronaries; 171 pts had significant coronary artery disease (CAD), of whom 48 had 1-vessel, 58 2-vessel and 65 3-vessel CAD. In this cohort, 138 of 171 pts with CAD (81%) had an abnormal SPECT imaging, whereas 26 of 40 pts (65%) without angiographic CAD also had an abnormal SPECT study. Thus, SPECT sensitivity in diabetic pts is similar to the expected values in non-diabetic pts. However, abnormal SPECT was unexpectedly prevalent in diabetic pts with normal epieardial coronary arteries, implying that perfusion abnormality due to small vessel disease is ubiquitous in such pts.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Monday afternoon, April 7, 1997

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21.4

22.1

LONG-TERM CHOLESTEROL-LOWERING T R E A T M E N T AND M Y O C A R D I A L P E R F U S I O N R Nohara, R Hosokawa, L Linxue, S Tamaki, T Hashimoto, M Tanaka, S Miki, S Sasayama Kyoto University Hospital, Kyoto, JAPAN

COMPARISON OF "CONVENTIONAL" WALL MOTION AND PERFUSION IMAGING WITH FI8-FDG SPECT IMAGING FOR IvIYOCARDIAL VIABILITY. MJ Henzlova, JM DeLaTorre, G Dangas, JA Diamond, J Machac. Mt. Sinai Medical Center, New York, NY USA.

Simvastatin is reported to improve lipid metabolisms and to regress coronary atherosclerosis. But, improvement of myocardial perfusion with Simvastatin has not yet been investigated using :°~TI-SPECT. At 5 pilot study centers, 18 patients with ischemic heart disease(IHD) were enrolled and 3 dropped out; the remaining 15(male/female = 10/5, 61.6+--8.2 yr) were compared with 23 control patients(C). Total cholesteroI, triglyceride and non-HDL cholesterol levels decreased significantly, and HDL cholesterol increased after a year. Exercise(E) and resting(R) ~°~TIscore(TS) were calculated based on integrated regional uptake scores. E-TS and R-TS improved 100% in the Simvastatin-treated group, however, C showed only 10% improvement (p<0.01). Pressure-rate product and exercise time increased with improved E-TS, suggesting central effect. It also showed that the higher the level of cholesterol improvement, the greater the improvement in TS tended to be(r=0.40). Final cholesterol less than 200 mg/dl and greater than 20% reduction showed greater TS improvement. These results indicated that long-term cholesterollowering treatment with Simvastatin definitely improved coronary perfusion as demonstrated by 2°~T1-SPECT.

F18-FDG SPECT was recently introduced as an alternative to F18-FDG PET. We wished to compare conventional imaging teclmiques, singly and combined, with FDG SPECT for detection of myocardial viability. 33 pts with Hx o f MI (LVEF=31 + 9%) were imaged with FDG and Gated MIBI (G-MIBI). 20 also had Echo and 13 TI-201(TI) imaging. Viability in each o f 16 segments was defined as 50% peak FDG, MIBI or TI uptake or preserved systolic thickening by G-MIBI or Echo, in 16 segments. Viability by FDG was the gold standard for positive predictive value (PV+) and negative predictive value (PV-) calculations. T..J MIBI ECHO G-MIBI PV(+) 90% 94% 88% 86% PV(-) 55% 72% 59% 79% When non-viability by MIBI(162 segs) was combined with absence of systolic thickening, the PV(-) increased to 85% (61/72) for G-MIBI and 87%(59/68) for Echo(p<0.05). We conclude that the PV(+) o f conventional methods is acceptable compared to FDG SPECT. The PV(-) is acceptable when MIBI or TI uptake o f <50% is combined with absence o f thickening. Referral for FDG-SPECT imaging can be limited to patients with highest incremental diagnostic value.

21.5

22.2

EFFECTS OF CARDIAC ADRENERGIC NEURONS ON ENDOTHELIUM -DEPENDENT AND -INDEPENDENT CORONARY VASODILATION IN HUMANS M.Di Carli, M.Tobes, T.Mangner, A.Levine, O.Muzik, P. Chakroborty, T.B.Levine. Wayne State University, Detroit, Michigan, USA.

IMPROVEMENT OF GLOBAL LV FUNCTION AFTER REVASCULARIZATION PREDICTED BY F18FLUORODEOXYGLUCOSE SPECT.

The endothelium modulates the ability of the coronary vascular bed to dilate and thus increase myocardial blood flow (MBF) in response to adrenergic stimulation. To determine the role of spontaneous or activated cardiac efferent sympathetic signals in the regulation of MBF, we studied t4 transplant (Tx) patients (55_+9 yrs) with angiographically normal coronary arteries and no evidence of rejection, and 8 normal subjects. We used PET to delineate sympathetic innervation with [C1l]hydroxyephedrine (HED), and measure MBF with [N-13]ammonia in reinnervated and denervated coronary territories of Tx patients under basal conditions, during adenosine-induced hyperemia, and in response to sympathetic stimulation by the cold-pressor test (CPT). In the Tx patients, HED uptake was near-normal in the LAD (82+6% of normal, P=NS), but decreased in both the LCX and RCA territories (46-+3% and 39-+2% of normal respectively, P<0.01). However, basal and hyperemic MBFs were similar in all territories. In contrast, the magnitude of MBF increase in response to CPT was lower in the RCA than in the LAD territory (16-+5% vs 46+9.5%, P<0.05), despite the fact that changes in cardiac work and circulating catecholamines were the same in all regions. The magnitude of MBF increase during CPT exactly mirrored the results of liED uptake. No differences in MBF were observed in the normals. In humans, rest and hyperemic MBFs are not significantly affected by basal levels of adrenergic tone. However, the degree of MBF increase in rcsponse to sympathetic stimulation is related to the magnitude of regional norepinephrine content in cardiac adrenergic nerve terminals. This relation may affect the extent of coronary flow abnormalities in patients with cardiac sympathoneural dysfunction.

Jeroen J Bax, Jan H Cornel*, Frans C Visser**, Paolo M Fioretti#, Arthur van Lingen**, Cees A Visser**. Leiden, *Alkmaar, **Amsterdam. #Rotterdam, The Netherlands. The aim of the current study was to evaluate the efficacy of Ft8-fluorodeoxyglucose (FDG) and single photon emission computed tomography (SPECT) to predict improvement of global LV function after revascularization. Patients with poor LV function (n=22, LVEF <30%), underwent FDG SPECT during hyperinsulinemic glucose clamp, early thallium-201 SPECT (to assess perfusion) and resting echocardiographv (to assess regional contractile function). The techniques :were analyzed using a 13-segment model. Dysfunctional segments showing either normal perfusion or" Iiypoperfusion with increased FDG uptake were considered viable. Global LV function was evaluated before and 3 months after revascularization by echocardiography and/or radionuctide ventriculograpby. An l'mprovement of LVEF >5% was considered significant. A patient was considered to have substantial viability when 3 or more dysfunctional segments were viable on FDG SPECT. FDG SPECT correctly identified t2/12 (100%) of the patients that improved in LVEF as viable, whereas 8/10 (80%) patients that did not improve in LVEF were identified as nonviable. Moreover, in the patients with 3 or more viable, dysfunctional segments the LVEF increased from 25+6% to 32_+6% (P<0.01). In the remaining patients the LVEF was unchanged (24_+6% vs 25_+6%, NS). These results indicate that FDG SPECT can identify patients who improve in global LV function after revascularization.

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M O N D A Y P M A P R I L

Abstracts Monday afternoon, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

22.3

22.5

ASSESSMENT OF MYOCARDIAL VIABILITY: THE ROLE OF TC99M SESTAMIBI GATED SPECT A. Maes, J. Nuyts, W. Flameng, LPh. Cambier, M. Borgers, L. Mortelmans, U.Z.K.U. Leuven, Belgium

SESTAMIBI TOMOGRAPHY AND LOW-DOSE DOBUTAMINE ECHOCARDIOGRAPHY IN THE PREDICTION OF DELAYED RECOVERY OF PERFUSION AND CONTRACTION AFTER MYOCARDIAL INFARCTION.

In 18 patients with CAD and anterior walt motion abnormalities, a gated Tc99m-Sestamibi resting study and a nuclear angiography were performed preoperatively. During revascularisation, a biopsy specimen was obtained from the LV anterior wall. Three months after surgery, radionuclide angiography was repeated. Optimal thresholds were calculated for Tc-99m-Sestamibi summed and enddiastolie perfusion maps and for wall thickening using improvement of regional ejection fraction as gold standard by maximising [100 - (% false positives) - (% false negatives)]. The optimal threshold was 60% for both summed and enddiastolic perfusion maps. Sensitivity and specificity values were 69% and 80% respectively for the summed perfusion maps and 71% and 100% for the enddiastolic perfusion maps. Concerning the wall thickening data, an optimal threshold of 20 degrees for thickening phase resulted in a sensitivity of 69% and a specificity of 80%. Sensitivity and specificity values for thickening amplitude (threshold = 0.4) were 73% and 71%. Analysis of the histological data revealed 23+12% fibrosis in the patients with preserved MIBI uptake, while 60-219% fibrosis was found in the group with MIBI uptake values <60% (p<0.01). 24+12% fibrosis was found in the patients with preserved wall thickening while 53+24% fibrosis was found in those with decreased wall thickening (p<0.0l). From these data it can be concluded that both perfusion and thickening data can be used for identification of myocardial viability using Tc-99m Sestamibi. Analysis of wall thickening supported perfusion data and provided additional confirmation of the presence of viable myocardium.

A. Cuocolo, E. Nicolai, M.R. Grivet-Fojaja, A. Nappi, F. Squame, P. Sullo, A. Discepolo, L. Spinelli, M. Salvatore. Universit& Federico I1, Napoli, Italy. The aim of this study was to compare the results of low-dose dobutamine (5 gg/kg/min i.v.) 2D-echocardiography (echo) and those of Tc-99m sestamibi tomography in the identification of viable myocardium after myocardial infarction (MI). Thirty-one patients with recent MI were studied 14 days of MI (study 1) and after 9+3 months (study 2). At study 1, all patients underwent Tc-99m sestamibi tomography and dobutamine echo. Regional Tc-99m sestamibi activity and systolic function were assessed in 16 segments/patient. Of the 136 infarct-related segments with severe dysfunction at rest at study 1, 43 (32%) showed contractile reserve and 93 (68%) did not show contractile reserve at dobutamine echo. The majority (98%) of the 43 asynergic segments with contractile reserve had preserved Tc-99m sestamibi uptake (>_50% of peak). However, a substantial number (56%) of asynergic infarct-related segments without contractile reserve had preserved Tc-99m sestamibi uptake. Of these latter segments, 48% showed delayed recovery of perfusion and contraction at study 2. These results suggest that in patients with recent MI the evaluation of contractile reserve alone may underestimate the identification of dysfunctional but still viable myocardium compared to Tc-99m sestamibi tomography.

22.4

23.1

COMPARATIVE SENSITIVITIES OF WALL THICKENING, THALLIUM UPTAKE, AND F-18 FDG SPECT IN DETECTING MYOCARDIAL VIABILITY.

PROGNOSTIC VALUE' OF NORMAL REST TETROFOSMIN SPECT IN PATIENTS WITH A C U T E CHEST PAIN AND NONDIAGNOSTIC ECG IN E M E R G E N C Y DEPARTMENT. Frans J. Th. Wackers, Gary V, Heller, Stephen Stowers, Robert C. Hendel, Steve Herman, Jack Baron, Edouard Daher. Acute Chest Pain Trial, Yale U., New Haven, CT.

O. DePuey, M. Ghesani,M. Schwartz M. Friedman, K. Nichols. St. Luke's-Roosevelt Hospital and Columbia University, New York, NY To evaluate the comparative sensitivities in detecting myocardial viability of gated SPECT wall thickening (WT), delayed TI-201 SPECT (TL), and F-18 FDG SPECT (FDG), 15 patients (pts) with prior myocardial infarction and clinically suspected viability were studied. Each patient demonstrated at least one extensive ~ 30% of LV) and severe (<40% maximal myocardial tracer uptake) fixed perfusinn defect on rest/stress Te-99m sestamibi SPECT. A total of 26 major vascular territories had fixed defcets. Mean (&l SD) LVEF determined from gated perfusion SPECT was 27+13%. WT was assessed semiquantitativelyby the regional increase in myocardial intensity during systole, and was oonsidered normal when a >20% increase was observed. T1-201 SPECT was acquired 4 hours after resting tracer injection. Viability was considered present when regional defect T1-201 count density was at least 20% greater than on the resting sestamibi scan. FDG SPECT was performed independently using 10 mCi and a camera equipped with ultrahigh energy collimation. Criteria of viability were the same as for TI-201. In the 15 pts viabilitywithin the fixed sestamibi defects was manifest by preserved WT in 2 pts, delayed TL uptake in 4 pts, and FDG uptake in 7 pts. Two major vaseular territories with fixed defects were judged viable by WT, 5 by TL, and 11 by FDG (p=.01). In each territory with delsyed TL uptake, FDG uptake was relatively greater. We conclude that FDO SPECT is mol-esensitive than either gated sestamibi WT or delayed TL in detecting viability.

Rest Tc-99m Tetrofosmin (Tetro) SPECT imaging in the emergency department (ED) in patients (pts) with acute chest pain and nondiagnostic ECG has a high negative predictive value for detecting acute infarction(MI). The prognostic value of ED rest Tetro SPECT imaging was evaluated in 357 pts with chest pain and nondiagnostic ECG. All Pts were admitted to hospital and had follow-up (FU) in-hospital (IH) and for 30 days (30d). Managing physicians were blinded to SPECT imaging results. Endpoints were ischemic death, recurrent MI and revascularization (Revasc). Events IH(#pts) 30d(#pts) Total(#pts) Death 0 0 0 MI 20 0 20 Revasc 34 2 36 At 30d FU, 62 pts with abnormal ED Tetro SPECT had significantly more acute MI (21% vs. 2%, p<0.001) and more Revasc (23% vs. 7%, p<0.001) than 295 pts with normal rest ED Tetro SPECT. Thus, abnormal rest ED Tetro SPECT in pts with chest pain and nondiagnostic ECG identifies pts with higher clinical need for Revasc during subsequent 30d follow-up.

Journal of Nuclear Cardiology V o l u m e 4, N u m b e r

Abstracts

1, Part 2

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M o n d a y a f t e r n o o n , A p r i l 7, 1997

23.2

23.4

PROGNOSTIC VALUE OF ADENOSINE THALLIUM201 SPECT AFTER ACUTE MYOCARDIAL INFARCTION: A PROSPECTIVE TRIAL. Habib A. Dakik, J'ohn A. Farmer, Mario S. Verani, ZuoXiang He, Juliet A. Wendt, John J. Mahraarian.Baylor College of Medicine, Houston, Texas, USA

EXERCISE TOLERANCE AND LEFT VENTRICULAR FUNCTION IN PATIENTS WITH MYOCARDIAL INFARCTION FOLLOWING REPERFUStON THERAPY AND ANGIOTENSIN CONVERTfNG ENZYME INHIBITION L.H.B. Baur, E.E. van der Wall, B.L.F. van Eck-Smit, E. van der Velde, J.J. Schipperheyn, A.V.G. Bruschke. Leiden University Hospital, Leiden, The Netherlands

We have previously shown in a retrospective study that the total and ischemic perfusion defect size (PDS) quantified by adenosine TI-201 SPECT predicts cardiac events in pts after myocardial infarction (MI). In this prospective study, we performed adenosine SPECT in 86 consecutive pts 4,54" 2.9 days after MI. Over 8.54-5 months, cardiac events occurred in 25 pts: death (N=6), MI (N=I0), unstable angina ~=5), CHF (N=4). Predictors of cardiac events were: Cardiac Event No Cardiac p ] 0 =25) Event (N=61) Value Total PDS (%LV) 36~-19 [schemic PDS (%LV) 154"12 LV EF (%) 40-2:15 494"12 1012 I Diabetes (%) 54 2l .oo3 I Cardiac events occurred in 80% of pts with vs only 36% ofpts without a large (_>20%) PDS (p<.0()l). Of note, 5 of 6 pts who died had PDS _>40%. Conclusion: This prospective trial confirms the important role of adenosine SPECT in risk stratification after acute MI.

I

I

23.3 PREDICTION OF FUNCTIONAL RECOVERY AND PROGNOSIS IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION USING 1231-BMIPP AND THALLIUM-201 SPECT : A MULTI CENTER TRIAL BY 14 INSTITUIONS, *T.Nishimura, S,Nishimura, T.Kajiya, H.Sugihara, K.Kitahara, K.Imai, T.Matsumura, N.Takahashi, H.Yoshida, T.Osada, K.Terada, T.Ito, H.Naruse. N.Iwabuchi. *Tracer kinetics, Osaka University Medical School. Osaka, Japan. The purpose of this study was to determine whether 6-methyl-p-(~2al) iodophenylpentadecanoic acid (~I-BMIPP) and thallium-201 single-photon emission computed tomography during subacute stage were useful for prediction of functional recovery and prognosis in patients with acute myocardial infarction (AMI). We retrospectively evaluated left ventrisular ejection fraction (EF) at discharge and at 3 months or more, improvement of EF from admission to discharge (±EF), o c c u r r e n c e of severe cardiac events (cardiac death or heart failure) and recurrent ischemia (non-fatal myocardial infarction or angina pain) in 201 cases followed for more than 3 months by means of ~231-BMIPP and thallium-201 during subacute stage. The best predictor of EF after AMI was tmI-BMIPP severity scores (SS) and _¢EFcorrelated well with thallium-201 defect size and the degree of difference in thallium-201 and ~I-BMIPP SS (mismatch). ImI-BMIPP SS tended to be large in patients with severe cardiac events. Occurrence of recurrent ischemia was high in the cases with small thallium-201 SS during the chronic stage and no improvement of mismatch from subacute to chronic stage. In conclusion, ~231-BMIPP and thallium-201 SPECT during subacute stage were extremely useful for patient management after AMI.

Left ventrtcular remodelling can be attenuated by reperfusion of the infarct related artery and by treatment with an angiotensin converting enzyme inhibitor. The purpose of this study was to assess the additional value of the angiotensin converting enzyme inhibitor enalapril on exercise tolerance and ventricular remodelling in patients treated with thrombolysis or coronary angioplasty. Methods: Seventy-one patients with an anterior wall infarction received in a double blind fashion 20 mg o.d. enalapril (E, n=36) or placebo (C, n=35), starting within 48 hrs after hospital admission. Trial medication was continued for one year. The influence of E on exercise tolerance and left ventricular enddiastolic volume (LVEDV), ejection fraction and diastolic function was assessed with exercise radionuclide angiography. Results: Exercise level of pts treated with C increased from 87.9=~.2.6.9 Watts 3 weeks after infarction to 104.5+33.6 Watts after one year (p<0.05). Enalapdl treated pts increased exercise level from 105.7+43.6 Watts to 114.3+38.5 Watts (p<0.05; E vs. C pNS). LVEDV increased during follow-up from 106.7:-z-46.4ml/m2 to 121.3+55.5 ml/m2in C pts and from 99.3:t:38.9 mVm2 to 120.4~55.9 ml/m2 for E treated pts (p<0.05). No difference between E and C was observed. Left ventricular ejection fraction was similar in both groups. Three weeks after infarction, peak filling rate was 2.5=l:0.8 EDV.s ~ for C pts and 2.4+1.1 EDV?s for E treated pts. After one year peak filling values were 2.2~0.8 and 2.3+0.8 EDV.s"~ (respectively, pNS). Conclusion: In pts with acute myocardial infarction, treatment with an angiotensin converting enzyme inhibitor following reperfusion therapy had no significant influence on exercise tolerance, left ventricular remodelling or diastolic function during one year follow-up.

23.5 Early Prediction of High Risk Patients With Multivessel Disease Role of Acute Imaging in Recen¢ MI Alia Ahd EI-Fnitah, MD; Molumted EI-Shafle; Helmy EI-Ghawaby; Ayman EI-Naggar and SherifMokhtar, MD, Critical Care Department, Cairo University, E=ypt To identify patients (pts) who need early intervention in the acute phase of myocardial infarction (MI), 15 pts (12 M, mean age 55:~5 yrs) with 1st acute MI were subjected to acute imaging, using Technedutw99 sestemibi injected immediately after admission, 3 planar images were acquired within 6 hours, A second set of images was acquired 72 hours later. Myocardiure at risk was quantified by s~niquantitative analysis technique via dividing the myacasdiurn into 15 segments and application of a ~oring system(0-3). Aseoreof0was assigned to segments with 70-100% of MCA, mild defect was asigned a more of 1, moderate defect a scoreof2, severedefectascoveof3. AIIptsweresubj¢ctedto coronary angiography one week after acute MI, and pts wereclassifiedinto 2 groups: single vessel disease (4 pts), mutlivessel disease (11 pts). Perfusinn defects outside segments of the infarct related a~ety (indicating iscbemia at distance) were looked for and the extent of myocardial salvage was assessed via estimating the score difference (SD) betwecothe2 setsnfireages. Reversibility index (RI) was estimated (RI= SD/initial score).

Out of the 11 pts with multivessel disease, 9 showed evidence of iscbemia at a distance in the 1st set of images with subsequent partial reperfusinn in the 2nd set of images. The mean scores in the infarct related segment~ in file 2 sets of images, PA were 1!.6~4.4, 7.1--L3.2, 29.4%d:11.2%. The corresponding mean scores, 17,I in non-infarct related segments were 2.4±2.1, 0.17±0.2, 90.6% .+.37.6% respectively, Then=was complete resolution ofischemla at distance in 7 pts (out of 9). None of the 4 pts with single vessel disease showed pcrfi~inn defects outside the infarct-related artery distribution.

Conclusion: In the setting ofacuteML earlypredictionof high risk pts with mnitiv~sal disease can be achieved non-invasively via acute ireaging, The high RI points to the presence of remote ischemia and multiplicity ofcerousry artery disease.

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Abstracts Monday afternoon, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

24.1

24.3

I:~ROGNOSTIC VALUE OF RADIONUCLIDE VENTRICULOGRAPHY WITH INOTROPIC STIMULATION IN PATIENIS WITH LEFT

LV FUNCTION IN CARDIAC TRANSPLANT PATIENTS-- IMPACT OF CAD. Roxanne A. Rodney,Akosua Boateng, Y.Olowe, R. Alejandro. Columbia University,N.Y., N.Y.

VENTRICULAR D Y ~ O N

Ant6nio Ventesa, Marisa Tmbulo, Victor Gil, Manuel Almeida, Luis Bronze, Jolt Calqueiro, Ricardo Seabra-Golues. Serviqo de Cardiologia. Hospital de Santa Cruz, Carlmxide, PORTUGAL. To study the proguostic value of radionuclide ventriculography with inotropic stimulation in patients with significant left ventricular dysfunction (LVEF 35%) we evaluated 70 pts, 54 12 years old, including 44 with isehemie heart disease (IHD) and 26 with idiopathic dilated cardiomyopathy (DCM). LVEF ~wascalculated at rest (23 7% ) and after graded infusion 0f epinephrine or dobutmafine(inot) (29 11%). During a 41 12 mo. follow-up, 29 cardiac deaths occurred (15 in IHD, 14 in DCM). Using a cutoffof 25%, inotLVEF was superior to restLVEF in discriminathlg Kaplan Meier estimated survival. Survival at 1, 2 and 5 years (95%CI for 5 years) was respectively 100, 90 and 58% (31-86) for restLVEF>25%, 75, 64 and 33% (14-51) for restLVEF<_25% (p=0.03), 97, 86 and 67% (46-87) for inotLVEF>25% and 66, 57 and 19% (2-35) for inotLVEF<_25%(p<0.0008). Two-year survival for inotLVEF > and _< 25% was respectively 72%, 92% in IHD and 36%, 71% in DCM.

In conclusion, although LVEF is a powerful variable with established prognostic value, LVEF under inotropic stimulation had, in this series, better ability h~ predicting nlol-tality, suggesting that its detemfination can intprove prognostic evaluation in I0ts with huportant left ventricular dysftmction, and may be useful in selecting patients for heart transplant.

Cardiac transplant(CTx) pts have lower EF's compared with nls, but the influence of Tx CAD,which limits long term survival,is unclear. Pts had radionuclide angiography1110 MBq Tc99m, coronary anglo,and biopsy w/i 1 wk(acute rejection excluded);75 pts were analyzed. 22 pts were _<12mo, 17 pts13-24 mo, 21pts 25-36 mo, and 15 pts 37-48 mo s/pTx . 27 pts (grl) had CAD, 48 (gr2) did not. LVEF in grl and 2 did not differ at _<12 mo (63+ 9 vs 60 + 12) and at 13-24 mo(66+8 vs 64 + 8). But at 25-36mo (60+_8 vs 66+ 9)p<0.05,and at 37-48 mo (54+-9 vs 66+8)p< 0.01,grlpts had a lower EF. Thus CTx pts with CAD have a reduction in LV function beyond the 2nd yr s/p Tx, and may then require closer f/u.

24.2

24.4

LEFT VENTRICULAR FILLING IN SEVERE PULMONARY DISEASE I. P. Clements, L. J. Olson, P. D. Scanlon Division of Cardiology, Mayo Clinic, Rochester, MN

QUANTITATION OF MANAGEMENT RISKS IN CORONARY ARTERY DISEASE: AN EJECTION FRACTION-BASED TOOL PG Supino, EM Herrold, C Hochreiter, JS Borer Cornell Medical Center, New York, NY, USA:

1

Rest LVEF

.~o.6 t ~o.,~ I-

~ <25 % I 1

I 2

Inotropic LVEF

. . . . I .~o.4

u~0.2 0 ~-0

1

~ 0.2 0

3

4

5ears6

0

I

2

3

4

5yearsfi

In order to assess if severe pulmonary disease impaired left ventricular (LV) filling, 10 patients with severe obstructive airway disease (COPD, forced expiratory volume in one second <40% of predicted) were studied using rest blood-pool radionuclide ventriculography. Age (yr), peak filling rate (PFR, LV end-diastolic volumes/sec), and fractions of LV stroke volume filled in the first half of the filling period (HFF), during the rapid filling period (RFF) and during atrial filling (AFF) are tabulated and compared with values from 60 patients without COPD, cardiac disease, or hypertension (Normal). Age (range) 149+9 (28-72)166+8 (51-76) 1 .0001 I PFR I 3.12+0.65 I 2'21-+0.341.00011 HFF 10.71+0.11 [0.50-+0.11 1.00Oll [RFF 10.78-+0.09 [0.59+0.15 1.00011 I AFF 10.17+0.08 10.28+0.16 1 . 0 0 2 1 Analysis of covariance including age and pulmonary status indicated that the presence or absence of COPD was an independent determinant of PFR (p=0.007), HFF (p=0.003), and RFF (p=0.003) but not AFF. Thus, severe COPD significantly impaired early LV filling independent of age and may be related to RV and LV interaction.

Proper management decision making is based on defining expected outcomes with alternative therapies in pts with sinailar pre-therapy characteristics. To create a management tool for pts with coronary disease(CAD), we compared outcome (death, nonfatal infarction) in medically (MED,n=52) or surgically (CABG,n=ll3)-treated pts with 3 vessel CAD categorized by change(A)in LV ejection fraction(EF) from rest to exercise at study entry prior to 9 yr follow-up. Relative cardiac event rates among MED vs. CABG pts were compared by Cox proportional hazards model and stratified to 3 sequential 10% increments of index ALVEF (+2 to -7, -8 to -17 and -18 to -27), revealing a direct(p=.04) relation between preoperative ALVEF and CABG benefit. Relative hazards were equivalent among MED vs. CABG pts with no or relatively mild index ischemia, and rose 5-fold among those most severely ischemic, according to the equation: Relative Risk=.9+l.68xAEF. This relation helps rationalize selection among CABG vs. MED Rx.

Journal of Nuclear Cardiology Volume 4, Number I, Part 2

Abstracts Monday afternoon, April 7, 1997

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24.5

25.2

ADVERSE PROGNOSIS FOR HIGH RESTING LEFT VENTRICULAR EJECTION FRACTION IN OLDER PATIENTS. A.F. Jacobson. VA Medical Center, Seattle, WA, USA

ENHANCED DETECTION OF VIABLE MYOCARDIUMBY TECHNETIUM(Tc)-99m-TETROFOSMIN IMAGING AND FIRSTPASS RADIONUCLIDE ANGIOGRAPHY (RNA) AFTER NITROGLYCERIN (NTG) ADMINISTRATION. A.Peix, A.L6pez, F.Ponce, J.Morales, A.Rodrlguez, C.Sin Chesa, AM.Maltas and D.Garcla-Barreto. Institute of Cardiology~ Havana, Cuba.

While normal (nl) resting left ventricuhu" ejection fraction (EF) is considered a good prognostic factor, the possibility that a very high EF, seen with hypertrophic cardiomyopathy and other pathologies, may be associated with an adverse prognosis in older patients (pts) has not been examined in detail. A review of >2000 consecutive resting Tc-99mlabeled red blood cell radionuclide ventficulography studies performed from 1987-1991 identified 848 pts age _>50 with normal LVEF (>50%) and clinical follow-up of _> 1 year Or until time of death. 461 pts (58%) died during follow-up; mean follow-up among survivors was 6.5 years. Five-year survival probability (5YS) was determined from KaplanMeier curves for pts grouped by age and LVEF, as follows. AGE--> EF 50-59%

50-60 0.596

EF 60-69%

0.758

I

60-70 0.554

->70 0.539

0.549

0.432

EF -> 70% 0.583 0.493 0.390 Within each age group, 5YS was lowest for pts with EFt_70%, although only statistically significant for >_70 year old pts (p<0.05 vs EF 50-69%). A higher nl EF (60-69%) was associated with better 5YS for 50-60 age pts (p<0.05). In pts _>70, high nl EF is associated with poorer prognosis.

To assess myocardial viability and its influence on ventricular function, 50 patients (pts) with a myocardial infarction were studied. Two Tctetrofosmin scintigraphies were performed:one at restandpost 0 . 6 m g N T G , and another after stress, including a rest and post-NTG first-pass RNA. Within 2 weeks all underwent a stress-redistri bution-reinjection Thallium(Tl)-201 seintigraphy. Of the 237 segments with post-stress reduced uptake, 36 improved at rest and 67 only after NTG. 64 of these with improved uptake were also viable on TI imaging. Among the 134 segments with reduced Tc-tetrofosmin uptake and no change after NTG, 109 were non viable on TI imaging. There were post-NTG segmental contractility improvement and LVEF increased~4% in 27 pts, of whom 25 were viable on Tc-tetrofosmin and 24 on TI. There was no significant difference between Tctetrofosmin and TI for viability detection. We conclude that in infarcted pts, NTG administration during a Tc-tetrofosmin seintigraphy improves the detection of viable myoeardium.

25.1

25.3

INCREMENTAL VALUE OF INOTROPIC STRESS Te-99m SESTAMIBI SPECT INL~GING AND ECHOCARDIOGRAPHY FOR THE DETECTION OF MULTI-VESSEL DISEASE R. S. Khattar, R. Senior, U Raval, A Lahiri. Department of Cardiology, Northwick Park Hospital, Harrow, UK.

rTHALLlUM-201 MYOCARDIALPERFUSIONALSPECTRUM IN PSEUDONORMAUZATION OF T-WAVES DURING ELECTROCARDIOGRAPHICTREAD-MILLEXERCISETEST. D. R. Jangid, S. Chakraborty, N. Raina, N. Trehan. Escorts Heart Institute & Res. Cntr, New Delhi-25. INDIA.

Exercise electrocardiography (ETT) is sub-optimal for the identification of high risk patients with multivessel disease (MVD). We investigated 100 patients undergoing coronaryangiography to assess whether simultaneous inotropic stress Tc-99m sestamibi SPECT imaging (MIBI) and echocardiography (echo), using either dobutamine or arbutamine, cotdd enhance the identification of MVD in conjunction with ETT. MIBI and echo were analysed using a 12 segment left ventricular model. Reduced tracer uptake or wall thickening in at least 2 coronary, artery-territories at peak stress were considered diagnostic of MVD for MIBI and echo, respectively. Angiographic evidence of >_50% stenosis was considered significant and 51 of the 100 patients had MVD. Univariate analysis showed age, previous MI, MIBI and echo, but not ETT, to be predictive of MVD. The addition of either MIBI or echo to clinical variables enhanced the detection of MVD (p<0.001; RZ=0.29 for both teclmiques) and adding both had further incremental value (p<0.001; R2=0.35). Therefore, assessment of both perfusion and function by inotropie stress testing has an important role in the detection of MVD.

Clinical significance of pseudonormalization of T-waves (pn-TW) on electrocardiographic tread-mUl exercise testing (TMT) is still not clear. A previous study by others using standard stressredistribution 201-Thallium (201-TI) myocardial perfusion imaging (TMPI) in 82 patients concluded that pn-TW was largely a result of myocardial scarring. Since an electrocardiographically changing / dynamic process (viz. pn-TW) during TMT is unlikely to be present in a physiologically inert (viz. infarcted) myocardium, we undertook to study pn-TW further by multi-phase (MP) TM PI. 128 consecutive patients, who demonstrated pn-TW during TMT-exercise performed as a part of routine MP-TMPI (Stress, Redistribution, Re-injection) were analysed. 93 patients (72.66%) with pn-TW had jeopardized but viable (ischemic /hibernating) myocardial segments. 9 (7.03%) showed pn-TW in association with infarcted segments. 26 (20.31%) had apparently normal myocardial segments; although some of them might have been 'stunned'. This is the largest nuclear imaging study elucidating and stratifying myocardial patho-physiological states underlying pn-TW. pn-TW is herewith concluded to be a marker ot jeopardized yet viable myocardial segments, and not the myocardial scarring /infarction as previously concluded.

M O N D A Y P M A P R I L

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Abstracts Monday afternoon, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

25.4

25.6

LUNG/HEART RATIOS ON IMMEDIATE AND DELAYED POST-STRESS IMAGES WITH Tc-99m SESTAMIBI(MIBI): IS LUNG ACTIVITY INCREASED OR HEART ACTIVITY DECREASED? G.A.Hurwitz. Victoria Hospital, London, Canada.

COMPARISON OF SESTAMIBI TO TETROFOSMIN: CARDIAC, LUNG & LIVER UPTAKE IN THE SAME PATIENTS

Increased lung uptake on post-stress images with MIBI may identify Severe disease and adverse prognosis; however, this sign has been underutilized. In a series of 1600 stress perfusion studies, we assessed lung and myocardial countdensities and their ratios(L/M)on immediate(IMM) and 1 h delayed(DEL) images. Muttifactorial analysis was used to compare image statistics to (i) dose (normalized for body weight), (ii) protocol (same- vs separate-day rest/stress), and (iii) result of tomography. Lung. and myocardial activities were strongly (p<0.0001) related to all3 factors. L/M ratios were not influenced by dose or protocol. In comparison with angiographic nonnals, increased ratios were found in 16% of IMM and 8% of DEL images. Further analysis on separateday studies showed reductions in dose-normalized counts in myocardium by 12% for IMM (p<0.0001) and 5% for DEL(p=0. l ), and increases (p<0.0001) in lung by 23 % and 46% respectively. Thus, increased L/M with MIBI is primarily the result &increased lung activity, consistent with its use as a sign of left ventricular decompensation.

Nadia Moussavi & Steven Port, Cardiovascular Associates, Ltd., Milwaukee, WI, USA A potential advantage of Tetrofosmin (Tatro) over Sestamibi (Mibi) imaging is more rapid liver clearance. We compared heart (H), lung (Lu) and liver (Li) activity and the H/Lu & H/Li ratios in 24 patients imaged with both Tetro & Mibi during Persantine (N=IS) or exercise (N=6) stress and at rest. Counts were measured on anterior planar projections of SPECT acquisitions using the average of 3-4 measurements in each organ. Data are shown as cts/pixel for stress (20 sec/image) and rest (40 sec/image). STRESS STRESS REST REST

MIBI TETRO MIBI TETRO

H 73±42 60±40* 49±21 47±23

Lu 29±16 24±16, 1726 1829

Li 84±33 68±29* 45±20 39±18

H/Lu 2.5±.3 2.5±.3 2.9±.8 2.7±.4.

H/Li 0.9±.4 0.9±.4 1.2±.5 1.2±.3

*p ~0.02 compared to MIBI During stress H, Lu & Li counts were lower with Tetrofosmin but the ratios were identical. Tetro does not appear to offer any advantage and with lower counts in the target organ may have a disadvantage compared to MIBI.

25.5

25.7

ECONOMICALLY OPTIMIZED USE OF PERFUSION-FUNCTION STUDIES FOR PROGNOSTIC ASSESSMENT Rory ~ d a , DarfielS.Bemm, LesleeJ. ~qaw,13¢0zBereri, JacobFad,HosenKiat,IshacCohen,JohnF ~ Geo~ A. Dimqond.~ M e d i c a l C.~er, LA, CA, USA.

DOBUTAMINE Tc-99m FURIFOSMIN SPECT IN THE DETECTION OF CORONARY ARTERY DISEASE.

Wehaveprevbuslyreportedth~ peakemdse fast pass otXak~ simaltaxously wkh S~ECFuskagTc-99m~ yields p ~ i c v a l u e md ~dmced iisks t r a ~ x Wenowevah~ethe opt~/utfl~/on ofFP. Weewak~edthisquestion~a 1210patiaas (pts) (71%rmle)who mkaweta stresssestm'di ff'ECI"w~FP. Pts wx~ followedup f o r a ~ o f l 8 immhs for l'~d evmts [HF_,~xliacdeath(8),myamlialk~fav.ion(33);overaUrote 35%] and 51 pts w~h em'y~ n (<60days)wereew.hded f i ~ m a p ~ ~Mysis(3.0%).Costswerebasedupon 1996U.S. Medicarepayrm-a. 9raters em'rix~ (a) SPECI"ox~y,(b) Fp only, (c) ~t3CT+FP, (d) FP, SPECT~FP EF<60.Cal-~z, mk~ h allpts with~ t~-ts ~trmd. ThettseoflxXhFP + ~ECT kkntif~ the n ~ t HE (88%).Theuseof(d) hadthe bwest ovffallc~t,but ~ fewerHE (68%).TheuseofFP onlyhadtl~ bwest oostper HE andkkntif~ 83% ofHE ~ r r e~rdse FP cm knprove ~ECI" ~ I:~tat ahit~ cost,axt is ~a3st-effectivewl-~ usedabr~

Mustafa 13nlii, Btilent Turgut, Hakan Temiz, Mehmet L. Alkan. Gazi University Medical Faculty, Departmants of Nuclear Medicine and Cardiology. Ankara / Turkey. The purpose of this study was to evaluate the efficacy of Tc-99m Furifosmin SPECT following dobutamine infusion in the detection of CAD, using a short one day rest - stress protocole.29 cases (mean age: 52.7 + 9.1) with suspected CAD who had limitations to perform treadmill exercise were included in the study. All patients had coronary angiography (CA) within two weeks.8-10 mCi of Tc-99m Furifosmin was injected at rest conditions. 1 hour after the rest - SPECT acquisition, following dobutamine infusion (5mcg/kg/min.up to 40 meg) 20 mCi of Furifosmin was administrated. SPECT acquisitions were done 30 min. after rest and stress injections.A significant increase in PDP and no serious side effects were observed after dobutamine infusion. SPECT data were evaluated using 20 segments 5 point scoring system ( 0: normal, 4: absent uptake). According to CA results significant stenosis ( >50 % ) were detected in 11 LAD, 7 LCX and 10 RCA territories. The sensitivity and specificity of rest - dobutamine Tc-99m Furifosmin SPECT were; LAD: 90%, 88%, LCX 85%, 95%, RCA: 88%, 90%, Overall: 88%,91% respectively. In conclusion, Dobutamine Tc-99m Furitbsmin SPECT is an efficient technique in the detection of CAD (accuracy: 90%) in patients who had limitations to perform exercise test.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Monday afternoon, April 7, 1997

25.8

25.10

IS ECG LEADS LOCATION OF ST SEGMENT DEPRESSION (ST,[,) DURING EXERCISE TESTING ABLE TO PREDICT THE DISTRIBUTION OF REGIONAL MYOCARDIAL ISCHEMIA? A.R. Galassi, R. Fort, R. Grassi, C. Mammana, C. Tamburino, A. Virgilio, G. Giuffrida. Institute of Cardiology, University of Catania, Italy.

[CHRONOTROPIC INCOMPETENCE AND MYOCARDIAL PERFUSION IMAGING IN PATIENTS WITH CORONARY ARTERY DISEASE JA Quion, L Padula, LJ Shaw, KL Kesler, A Shehata, M Travin, D Waters, GV Heller. Hartford Hospital, University of Connecticut, Hartford, Connecticut, USA

It is still controversial whether ST,[. during exercise testing might be able to predict the location of ischemia related diseased vessel. To this end 18 eonseculive patients (pts) (mean age 54_+10 years) with angiogmphically documented isolated single coronary artery disease (_>70% diameter stenosis), matched stress-induced 99mTe-TetrofosminSPECT reversible perfusion defects (RPD), positive exercise testing (>1 mm ST,[,) and no previous myocardial infarction, were selected. Symptom-limited exemise testing were performed off treatment, and the number and distribution of RPD by scintigraphy &sscssed using a 16 segment model and a 0--4 score index. None of the pts showed >1 mm ST,I, in inferior leads (II-III-aVF) alone. Eight pts (44%) showed _>I mm ST,[- in precordial leads alone: V2-V6 in 1 patient, V3-V6 in 3 pts, V4-V6 in 3 pts, and V5-V6 in 1 patient (Group I). The remaining 10 pts (56%) showed >1 mm ST,I, in bolh inferior and precordial leads: IMII-aVF/V3-V6 in 2 pls, II-III-aVF/V4-V6 in 6 pls and II-IIIaVF/V5-V6 in 2 pts (Group tI). No differences between group I and lI pts were observed regarding the number of RPD, rate-pressure product and lime at peak exercise. Results were: Anglography 99mTc-Telmlbslnin RPD Group I Group II p Left anterior desc. 0at antero-septal 5 6 NS Circumflex art. infero-latcml 1 1 NS Right coronary art. inferior 2 3 NS Thus, the location of ischemia related diseased vessel cannot be predicted on the basis of ECG leads location of ST,[, during exercise testing.

Chronotropic incompetence (CI) during exercise testing has been associated with a greater risk for subsequent cardiac events. To examine the relationship between CI and myocardial perfusion imaging, 1869 patients referred for Tc-99m sestamibi exercise stress testing were examined. Patients on beta-blockers, calcium blockers, or were unable to complete 6 minutes of exercise were excluded. Clinical follow-up of cardiac death/myocardial infarction was for 1.4 + 0.7 years. Relative risk was determined by the Cox pro~portional hazards model. P value RR (95% CI) Clinical risk 0.31 0.58 No. ofischemic areas 11.0 0.0009 1.63 (1.22-2.18) Peak HI{ < 110 bpm 8.3 0.004 2.89 (I.4-5.94) Conclusion: Both the number of ischemic defects and chronotropic incompetence during nuclear stress testing are associated with a higher risk of cardiac events.

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26.1

EVALUATION OF AN ATTENUATION CORRECTION METHOD ON PATIENTS WITH LOW LIKELIHOOD OF CORONARY ARTERY DISEASE (CAD) UNDERGOING THALLIUM-201 (TI-201) CARDIAC SPECT P. Chouraqui, S. Livschitz, J. Baron, M. Wilk. Sheba Medical Center, and Tel Aviv University, Israel.

VENOCONSTRICTION IS IMPAIRED DURING VOLUME UNLOADING IN CHRONIC HEART FAILURE. J Atherton, H Thomson, D [acfarlane, W Fong, T Moore, K Wright, G Muehle, L Fitzpa Lck, M Frenneaux. Department of Medicine, University of Queen and, Brisbane, Australia

Attenuation artifacts are a major source of errors in the interpretation of myocardial SPECT images. We evaluated an attenuation correction method (TransACT, Elscint Inc.) on 42 consecutive patients, with low (<5%) likelihood of CAD, undergoing stress/rest TI-201 myocardial SPECT imaging with simultaneous transmission-emission imaging using a moving gadolinium-153 collimated line-source. Uncorrected (U) and corrected (C) data were analyzed using polar maps divided into 31 segments to compare the homogeneity of uptake. The mean value (in counts/pixel normalized to the hottest pixel) of U data was significantly smaller and the standard deviation significantly larger than that of C data.

Uncorrected 2604 sgts

Corrected 2604 sgts

P

Stress images 74.8±10.2 80.3±7.7 .0001 .0001 Rest images 76.4±9.4 79.2,-7.9 Conclusion: The results confirm the improved homogeneity of TI-201 uptake using this attenuation correction method.

During volume unloading, pati ats with chronic heart failure (CHF) develop attenuated arteriol~ vasoconstriction or paradoxical vasodilation. We hypothesize that venoconstriction may also be impaired in such patients dur g volume unloading. We assessed changes in the forearm veno volume-pressure relation using a radionuclide technique duril : volume unloading achieved by application of 20 mmHg lower. ody negative pressure (LBNP) in 10 CHF patients with LV ejection "action<35% (58+7 yrs, 7 mate) and 13 controls subjects (55+7 yr~ l0 male). Following red blood cell labeling, the subjects lay su~ ~e and a sphygmomanometcr was placed around the upper arm. F -earm counts were obtained at 0, 10, 20 and 30 mmHg venous oc uding pressure before and during LBNP. Linear regressions we: performed on the venous volumepressure plots and the unstr~ ;ed forearm vascular volume was defined as the intercept on the ,olume axis. Changes in unstressed volume reflect changes in vet us tone. CHF patients developed a smaller reduction (mean+SD) i unstressed forearm vascular volume during LBNP compared with a e control subjects (-5.3+5.9% cf. -[0.4+4.0%, p<0.05). One CI- patients developed an increase in forearm vascular volume (ie, a ecrease in venous tone), a response not seen in any of the control :ubjects. The slope of the volumepressure relationships did n o t kange during LBNP suggesting that there were no changes in ven ~ts compliance. Venoconstriction is attenuated during volume unlo: ing in patients with CHF. This may partly reflect reduced barorefle sensitivity and probably contributes to orthostatic intolerance know: Looccur in such patients.

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IV C N D A Y P IV A P R I L 7

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M O N D A Y P M A P R I L

Abstracts Monday afternoon, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

26.2

26.4

ASSESSMENT OF 123I-MIBG SPECT DEFECTS WITH CIRCUN~'EqLENCIAL PROFILE ANALYSIS IN ARRHYTHMOGENrlC RIGHT VENTRICULAR DYSPLASIA (ARVD). A. Manrique, *P. Loiselet, *P. Scanu, Y. Darlas, F. Quennelte, *G. Grollier, *JC. Poticr, (3. Bouvard, D. Agostini. Depts of Nuclear Medecine and *Cardiology, CHU Crte de Caen, France.

INNERVATION-PERFUSION MISMATCH AND POST -OPERATIVE TACHYARRHTMIA IN DIABETIC C O R O N A R y ARTERY DISEASE PATIENTS. M. Unlu S. Inamr, S. G0naydm,A. Gengel, L. GCkgCz. Gazi University Medical Faculty, Departments of Nuc ear Medicine, and Cardiovascular Surgery, Ankara TURKEY.

Myocardial s3.,mpatheticnervous dysfunction has been suspected in patients (pts) with ARVD. In order to assess regional sympathetic innervation, 14 pts (12 males, 2 females, age: 46+ 13) with proven ARVC and normal perfusiun on 2°ITI-SPECT underwent planar imaging and SPECT 4 hours after a bolus injection of 259 MBq of t231-MJBG (Elscint Apex 415). Global cardiac neuronal function was assessed with planar imaging by the heart/mediastinum ratio of t23I-MIBG uptake (HMR). Regional sympathetic innervation was evaluated qualitatively by visual analysis of I23I-MIBG SPECT using a 5 segments model, and quanthatively by circumferencial profile analysis (CPA). A control grmrp included 9 healthy volunteers. In pts, HMR was within normal range (pts: 236+39% vs control: 234+12%, NS). In 11/14 pts, 19/55 segments showed a significant 123I-M1BGuptake reduction (<50% of maximum activity) by visnal analysis. Using CPA, only 10 of these (53%) demonstrated a significant uptake reduction compared to control (ie, < mean value 2 SD). CPA was concordant with visual analysis only in anterior and lateral walls: anterior septal apical lateral posterior visual defects 5 2 4 4 4 CPA defects 5 0 o 4 l Conclusions: t231-MIBG SPECT visual amalysis overestinmtes adrenergic defects in posterior, apical and septal walls. Circmnferencial profile analysis should be performed for correctly assessing regional sympathetic dysinnervation in pts with ARVD

In order to investigate the potential role of left ventricular 13adrenergic innervation and perfusion mapping in the prediction of post-operative ventricular tachyarrhytmia in diabetic CAD patients , 1-123 MIBG and rest TI-201 SPECT were performed in 28 patients [ 16 non-diabetics (ND), 12 non-insulin dependant diabetics (D) ], with documented multivessel coronary artery disease prior to CABG. Anterior planar and tomographic 1-123 MIBG images were obtained in early and delayed periods after injection. SPECT data were evaluated regionally in 9 segments in three planes using a three-point scaling system (0= normal, 1= reduced, 2= absent or severely reduced uptake) for both tracers. Normal perfusion but reduced or absent 1-123 MIBG uptake in delayed views was evaluated as a mismatch patern. There was no significant difference in left ventricular ejection fraction between two groups ( ND: 41 + 13%, D: 38 _+ 17%). However, heart to mediastinum ratios of 1-123 MIBG uptake in delayed views were significantly lower in diabetics ( ND; 2.01+ .31, D; 1.71+. 15, p < .005 ). Innervation/perfusion mismatch was observed in 15 % of total segments in 4 patients ( 25% ) in ND group and 38 % in 10 patients (83%) in diabetics. After CABG, 1 patient in ND group (6 %) and 4 patients -1 fatal - in diabetic group (33%) developed VT. Innnervation / perfusion mismatch seems to be strongly related with the frequent occurance of VT after CABG in diabetic coronary artery disease patients.

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26.5

INFLUENCE OF PACING SITE ASSESSED BY RADIONUCLIDE VENTRICULOGRAPHY IN D I L A T E D CARDIOMYOPATHY. A. Le Helloco, J. L. AIberini, J. P. Hacot, P. Bourguet, C. Almange, Department of Cardiology, Kennes, France

EXERCISE TESTING IN IDIOPATHIC DILATED CARDIOMYOPATHY: WHICH TEST FOR WHAT USE ? M. Faraggi, A. Cohen-Solal, N. Delahaye, D. Czitrom, JM. Foult, C. Peker, D. Le Guludec.BichatHospital, Pads, France.

The aim of this study was to evaluate the mechanical activation sequence in patients with dilated cardiomyopathy (D.C.M.) and left ventricular ejection fraction (L.V.E.F.) < 30 %. l0 patients (pts) with idiopathic D.C.M. (6 pts) and ischemic D.C.M. (4 pts) and mean L.V.E.F. 23,2 % + 7,2 were implanted with D.D.D. pacing. A radionuclide ventriculography with global and septal (Sp) L.V.E.F, mechanical activation sequence : Standard Deviation (S.D.) and percentage of L.V.asynchrony (Asyn) were performed with different sites of VDD pacing: right ventricular apex (RVAP), outflow tract (RVOT) and simultaneous pacing (2 BOTH). RVAP RVOT 2 BOTH LVEF (%) 21,5 + 6 NS 235:7 NS 22,5 5:7 Sp LVEF (%) 18 5:5 NS 19 _+6 NS 18 + 6 S.D. (ms) 1495:9 p<0,01 1195:5 NS 1245:7 L.V. Asyn (% 16+5 p<0,05 6_+4 NS 10+3 RVOT pacing site improves mechanical activation sequence in patients with D.C.M. with better synchronism of activation of L.V.

Rest LV ejection fraction (LVEF) and exercise capacity are strong predictors of cardiac events in heart failure, although poorly correlated.We compared the LV response to 3 exercise tests used for cardiac rehabilitationand prognosisassessment. LVEF and LV volumes were continuouslymonitored with an ambulatory radionuclidedetector (VEST, CapintecR) in 13 pts with idiopathic dilated cardiomyopathy, at rest and during standardized exercises: upright maximal graded bicycle exercise, 2 stairs climbing(SC) and 6 minuteswalk test (W-I). bicycle 6 rain WT 2 SC restLVEF 22±9% 22±10% 24±11% exerciseLVEF 17±8%* 19±6% 21±10%* changes in EDV 15±10%* 10±6%* 4±4%* *p<0.05 between rest and exercise These 3 tests induce different patterns of response in LVEF and volumes : the 6 minutes walk test may be preferred for cardiac rehabilitation but only bicycle and stair climbing exercises inducesignificantLV impairment and can accurately assess the contractilereserve.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Monday afternoon, April 7, 1997

26.6

26.8

123I.MIBG HEART TO MEDIASTINUM RATIO (HIM) IN ARRHYTHMOGENIC VENTRICULAR DYSPLASIA CARDIOMYOPATHY (AVD/C) DIAGNOSIS. S. Severi*, R. Bettini, E. Lorenzi*, A. Bertoldi, M. Camerani*. Nuclear Medicine* and Cardiology-S.Chiara Hospital-Trente-Itaty.

DOBUTAMINE-INDUCED AUGMENTATION OF LEFT VENTRICULAR EJECTION FRACTION AS AN ASSES SMENT OF INOTROPIC RESERVE

IN PATIENTSW1THIDIOPATHICDILATEDCARDIOMYOPATHY Tarlk M. Ramahi, Mark A. Saari, Elizabeth Hsia, Forrester A. Lee, Barry L. Zaret, Yale University School of Medicine. New Haven, CT, USA.

The 123I-MIBG allows the landmarking of the Sympatetic Nervous System of the heart. In AVD/C patients (pts) the detection with 123I MIBG SPET is based on the presence in the left ventricle of regional defects. We tested if the association of the H/M ratio to SPET can improve the test's ability, MATERIALS AND METHQD$: we studied 5 controls and 37 pts with hyperkinetic ventricular arrhythraias, apparently normal heart and high performance, suspected to have AVD/C by invasive and not invasive Cardiological study and by Nuclear Medicine protocol comprehensive of a perfusory rest SPET and a rest (4 hours) 123I-MIBG SPET. The 123I-MIBG scan also included a planar anterior image of 1000 Kcounts to evaluate the H/M ratio between two kind of heart ROIs (ROIldrawn in the anterolateral wall-ROI2 in the projection of the all heart) and the mediastinal Rot located near the pulmonar apex. RESULTS: after the eardiological examination 16 pt. had no cardiomyopathy, 21 AVD/C (concealed forms) while the 5 controls were negative. The mean ROll and ROI2 H/M ratio of the controls showed a statistically significative difference (9<0.002) between the mean value of the AVD/C pt while this difference is not present respect the group of pt. with no cardiomyopathy. CONCLUSIONS: As demonstrated in our praevious papers the 123I-MIBG SPET scintigraphy is a necessary modality for mapping, in AVD/C, the left ventricle symphatefic nervous system involvement, The H/M ratio study gives an important information about the global sympatetic activity of the heart that may be useful to improve the test's accuracy of the test independently from extension and localization of the regional defect.

Patients with chronic heart failure (CHF) have a decreased inotropic response to intra-eoronary dobutamine infusion. In order to explore the role of dobutamine-indueed augmentation of LVEF as a measure of IR in patients with idiopathic dilated cardiomyopathy (DCM), 30 such patients with stable CHF (mean LVEF 25% + SD 8, range 11-38%) on standard medical therapy underwent intravenous dobutamine infusion at a dose of 10 t.tgm/kg/min, and equilibrium radionuelide ventrieulography (ERNA) was used to determine LVEF after 10 minutes of infusion. A wide variation was detected in the increase in LVEF (range 2-23 points, mean 12 ± SD 7). There was a weak linear correlation between the increment in LVEF (ALVEF) and resting LVEF (r=0.44, p <0.03) and resting RVEF (r=0A4, p <0.04). No linear relation eoutd be discerned between ALVEF and peak exercise oxygen consumption (mVO2). Of these patients, 17 underwent quantitative ERNA. In this group, mean increase in heart rate was 21 (+ SD 18). No linear relation could be discerned between ALVEF and resting HR, SBP, DBP, MBP, ehange in HR, SBP, DBP, MBP, nor in ERNA-estimated stroke volume and systemic vascular resistance. An inverse linear relation was detected between ALVEF and left ventrieular and diastolic volume (r=0.6, p<0.03). Conclusion: Patients with DCM and stable CHF exhibit a wide range of dobutamine-indueed augmentation of LVEF weakly proportional to ventricular function but not related to measures of afterload nor exercise capacity. This method of inotropie reserve assessment may have an independent prognostic role.

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26.9

IMPAIRMENT OF LEFT VENTRICULAR ADRENERGIC INNERVATION IN PATIENTS LISTED FOR HEART TRANSPLANTATION ..D. Agostini, G. Babatasi*, A. Belin**, P. Scanu**, M. Massetti*, Y. Darlas, G. Grollier**, JC Potter**, A. Khayat*, G. Bouvard. Departments of Nuclear Medicine, Cardiac Surgery,-*, Cardiology**, Caen, France.

Correlation Between Cardiac '~1- meta- iodobenzyl guanidine Imaging and Neurohormonal Activation in Patients with Congestive Heart Failure K. IUCHI, K. USUDA, T. NAKABAYASHI, T. ISHIKAWA Department of Internal Medicine, Toyama Prefectural Hospital, Toyama, Japan

The purpose of the study was to assess the sympathetic activity in patients with cardiac heart failure listed for heart transplantation (HTx). 123I-metaiodobenzylguanidine (MIBG) scintigraphy has recently evolved as a nonivasive method for the in vivo evaluation of sympathetic activity by measuring postganglionic prcsynaptic noradrenergic uptake. A consecutive series of 65 patients from 1991 to 1996 (52+10 yrs, 52 men, 13 women) with ischemic (n=33), idiopathic (n=32) cardiomyopathy, and left ventricular (LV) dysfunction entered the study. All patients underwent right and left catetberization, coronary angiography, radionuclide LVEF and planar MIBG scintigraphy. They were listed on clinical (NHYA funtional class III-IV, 32 (Ill) and 11 (IV)), cardiac-thoracic enlargment on xray-chest (>0.55, 0.58+0.08)) and reduction of left LVEF (<25%, 22+5%). Ten normal volunteers (44+_12 yrs) were also studied and served as control group. Cardiac MIBG function was assessed as the heart to medisatinum (H/M) activity ratio measured on the chest anterior view image acquired on gammacamera, obtained after intravenous injection of 185 MBq of 123IMIBG. Data from patients with congestive heart failure showed a significant reduction of cardiac MIBG uptake, when compared with control group (H/M : 104+20% vs 230+21%, p<0.003). Conclusion: These results indicate that cardiac adrenergic innervation is dramatically impaired in patients listed for HTx.

We studied the correlation between cardiac '231 metaiodobenzytguanidine (MIBG) imaging and neurohormonal factors in 28 patients with congestive heart failure. The initial and delayed MIGB images were obtained 30 and 180 min after MIBG injection, and the ratio of heart/mediastinum (E-H/M and D-H/M) and washout rates (WR) were calculated. Plasma norepinephrine (Nor), renin activity (PRA) and aldosterone (Aid) were measured as neurohormonal factors. Results: E-H/M D-H/M WR E-H/M D-H/M WR PRA r=-0.343 -0.340 0.521' Nor r=-0.4037 -0.387t 0.2]5 Aid r=-O.302 -0. 351 O.577* ~ p <0. 005, ~. p <0. 05 Conclusions : The clearance of MIBG from myocardium (WR) may be regulated by renin-aldosterone system in patients with congestive heart failure. The correlation with plasma norepinephrine and MIBG kinetics may be weak.

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M O N D A Y P M A P R I L 7

Abstracts Monday afternoon, April 7, 1997

Journal of Nucleaa"Cardiology January/February 1997, Part 2

26.11

26.13

DOES LEFT VENTRICULAR FUNCTION DIFFER BETWEEN MEN AND WOMEN? E. Klodas, T. Christian, T. Miller, D. Hodge, R. Gibbons. Mayo Clinic, Rochester, MN, USA.

IMPLEMENTATION OF TECHNETIUM-99m SESTAMIBI GUIDELINES: OPTIMIZING THE TWO DAY STRESS-REST PROTOCOL. J.M. Lavalaye, J.M Schoeder-Tanka, M.M.C. Tiel-van Buul, K.I. Lie, E.E. van der Wall, E.A. van Royen. Academic Medical Center, Amsterdam, the Netherlands.

Previous studies have suggested that there may be intrinsic differences in left ventricular function between men and women. To examine this issue, first pass left ventricular ejection fraction (LVEF) values were analyzed in 292 l patients (1884 men, 1037 women) referred for stress Tc99m sestamibi imaging. 20-30 mCi were injected on day l at rest as part of a 2 day sestamibi stress study and first pass LVEF was obtained from the bolus transit via a multicrystal gamma camera. A normal LVEF was >0.50. LVEF values varied significantlyby gender: Men (n=1884) Women (n=i037) p LVEF 0.58+.13 0.60+0.12 <0.001 LVEF>0.50 79% 86% <0.001 Multiple other clinical factors were associated with a normal versus an abnormal LVEF including: prior MI history, normal rest ECG, antianginal medication use, diabetes, hypertension, and lipid status. On multivariate analysis, all clinical and ECG factors above were independently associated with LVEF. Gender was the weakest of these with a p value of 0.02 providing only a 1% increment in the power of the model. Conclusion: Although women referred for Stress imaging have higher baseline LVEF values compared to men, this difference is modest after adjusting for markers of preexisting coronary artery disease.

Introduction: Previous studies demonstrated that in the two day stress rest protocol-methodfor Technetium-g9m Sestamibi SPECT (Tc-g9m) a significant part of the patients shows no abnormalities on both the stress and the rest scan. It was concluded that it is preferable to withhold the rest scan after a normal stress scan. This study was set up to evaluate this new protocol and set guidelines for the variety of protocols now used for Tc-g9m Sestamibi imaging. Methods: We studied 235 consecutive patients (136 men, 99 women, mean age 61 years). All patients had stable cardiac chest pain and underwent symptom-limited exercise Tc-99m Sestamibi myocardial imaging. The stress image was reconstructed and judged immediately after acquisition. In case of a normal stress-image, rest-imaging was cancelled. Results: In the first month of the study, the nuclear physicians / cardiologists were reserved and interpreted only 6% of the stress images as normal, 13% after 9 weeks, with a mean of 11% for the whole investigation period. The majority of the group with normal stress images concerned females (73%), while this was 42% in the total patient population. Conclusion:11% of all patients had a normal stress SPECT which allows to perform a stress-only procedure. Using a quantification method, the interpretation of the images is less subjective and the number of normal studies will increase. This implies a considerable reduction in radiation dose, costs, increased convience for an important subset of patients and reduction of waiting lists.

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26.14

STRESS-INDUCED ST SEGMENT ELEVATION OCCURS PREDOMINANTLY IN MEN: A CLUE TO THE GENDER-BIAS PUZZLE IN CORONARY ARTERY DISEASE TESTING? G.Y. Oudit, R.J. Burns. University of Toronto,Toronto, Canada.

BENEFICIAL EFFECT of ADDITIONAL ATROPINE INJECTION DURING DOBUTAMINE INFUSION FOR MYOCARDIAL PERFUSlON SPECT B.Caner, U.Uysal, A.Karanfil, L.Tokgozo~lu, O. Ugur, P.Ozgen, S Kes, C Bekdik. Hacettepe Univ Ankara, Turkey

Analysis of 71 consecutive patients (pts) with slress-induced ST segment elevation from a cohort of 7075 2°1TISPECT pts (1%) revealed 69:2 M:F preponderance. Published consecutive sedes distinguishing all pts by sex reveal similar findings: men women p_ BruceR eta/, Circ1988 11612428 20/803 .003 311139 9/92 .010 ElhendyAeta/, AJC 1995 Thisstudy: 69/4622 2/2453 <.001 TOTAL: 216/7189(.03) 31/3548(.01) <.001 Our cohort also comprised 1074 patients (15%) with stressinduced ST segment depression (STD), of whom 301 (28%) were women. 2°~TIreversibility was detected as follows: STE-men STE-women STD-men STD-women 45/69(.65) 1/2(.50) 660/773(.85) 125/301(,42)* *p
The aim of this study was to assess whether additional atropine injection during dobutamine infusion, eventually causing higher heart rates, improves the imaging capability of dobutamine myocardial TI-201 SPECT. Fifteen patients (all with angiographically proven CAD) were studied twice with dobutamine myocardial SPECT on separate days. The first myocardial SPECT was performed following dobutamine infusion in 3 rain dose increments, starting from 10 ug/kg/min and radioactivity was injected 1 rain prior to the termination of infusion (D protocol). The second SPECT was performed after the same D protocol except with the additional atropine injection during dobutamine infusion (D+A protocol). Maximal heart rate achieved at the end of D+A protocol was significantly higher than that of D protocol (153±13 vs1174-15 beat/min). Images of each patient were analyzed on a segmental basis by dividing myocardial tomograms into 17 segments.The total number of segments with true positive perfusion defect seen on D images (97) was higher than that on corresponding D+A images (109)(p>0.O5). Moreover the mean uptake of segments with perfusion defect (as % of the maximal activity measured in the reference region) on D+A images was significantly lower than that on the D images (59.94-11.9 vs 62.84-11.4 %, p<0.05). Conclusion:Addition of atropine during dobutamine infusion enhanced the diagnostic capability of dobutamine myocardial SPECT by inducing either more extensive or severe defects.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Monday afternoon, April 7, 1997

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26.17

THE IMPACT OF DIFFERENTIAL UPTAKE ON A TWO ACQUISITION THALLIUM-201 REINJECTION PROTOCOL. J.Cacciabaudo, M.Szulc, S.Goldsmith, T.Christian, Cornell Medical Center, New York, USA Reinjection (reinj) Thallium-20l (TI-201) imaging enhances detection of ischemia but is cunabersome due to the need to acquire 3 sets of images. To investigate the necessity of a 3 hour redistribution (redis) image, 51 pts (42 male, 9 female) with at least one post-stress defect following injection of 3 mCi of TI-201 underwent 3 hr redis tomographic acquisition followed by injection of 1 mCi of TI-201 and repeat acquisition 30 minutes later. Defects were scored on a 5 point scale and assigned to one of 3 coronary territories (CT). There were 80/153 (52%) hypoperfused CTs post stress (anterior 32, inferior 39, lateral 9). By conventional redis imaging 45/80 (56%) were fixed and 15 of these 45 (33%) redistributed. With reinj of the 35 reversible defects by redis, 15 (43%) redistributed fhrther with reinj, 16 (46%) remained fixed and 4 of 35 (11%) showed worsening consistent with differential uptake. This occurred in 3 pts (6%) and 5% of all stress induced hypoperfused CTs. C o n c l u s i o n : Elimination of 3 hr redis acquisition to attain a 2 acquisition reinj protocol may result in a small (5%) reduction in detection of ischemia compared to a 3 image protocol but is superior to a conventional redis 2 image protocol.

SPET 99mTc-TETROFOSMIN PERFUSION SPECT ONE DAY PROTOCOL IN THE DIAGNOSIS OF CAD C, Santaoa-Boado, A. Garc[a-Burillo, M. Campreci6s M, J. Castell, J CandelI-Riera, J. Cortadellas, T. Canela, S. Aguad~, J. Soler-Soler. Hospital General Universltari Vail d'Hebron. Barcelona. Spain. 99mTc-tetrofosmin (TTF) is a new perfusion agent with rapid blood clearance that allows stress-rest studios in a short time period. The aim of this study was to assess the diagnostic yield of the one day protocol of perfusion tomography with TTF. 763 TTF tomographic studies were performed between April 1995 and March 1996. Patients with previous myocardial infarction and other cardiac non ischemic diseases were excluded. 110 patients who had coronary angiography within 3-month period were evaluated (mean age 55.7, range 40-87). All patients performed a symptom-limited exercise test on a bicycle ergometer until exhaustion, symptoms or > 2 mm ST depression developed. At peak exercise 8 mCi of TTF were injected and 15 rain later SPET was recorded. One-two hours after the exercise injection, 2 4 mCi of TTF were injected at rest and imaging was repeated 15 rain later. Myocardial uptake was assessed through the consensus of three experienced observers who were unaware of the results of coronary angiography. Coronary stenoses > 5 0 % were considered as significant. The prevalence of CAD in our population was 6 5 % . We obtained 67 TP, 31 TN, 7 FP (5 inferior localization, 1 anterior and 1 lateral) and 5 FN (2 with three-vessel disease, 2 with 7 0 % LAD stenoses and 1 with 6 0 % RC stenoses). Sensitivity: 9 3 % , specificity: 8 2 % , accuracy: 8 9 % , positive predictive value: 9 1 % and negative predictive value: 8 6 % . In conclusion, the results of stress-rest short protocol with TTF in assessment of CAD seem to be as good as those with 201TI SPET or SESTAMIBI-two days protocol.

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26.18

M.M. BoomsT~, M.G. Niemeyer, A.H. Zwinderman. Pep<. or Cardiology and Nuclear Medicine, Martini Hospital, Groningen, The Netherlands

OPTIMIZATION OF ACQUISITION TIME TO FIND MAXIMAL DIFFERENTIAL UPTAKE IN REST REDISTRIBUTION TI-201 SPECT D.S. Lee, S.N. Yoon, J-K. Chuug, M.M. Lee, M.C. Lee, C-S. Koh. Seoul National University Hospital, Seoul, Korea

THE

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CL~CAL

VALUE

OF

99M-TC

TZTROFO~q~ffN

( M Y O V I ~ ) MY(X?JkRDIAL PERFu~ION IMAGING The aim of the study was to evaluate the significance of perfusion defects in 99m-Tc Tetrofosmin myocardial perfusion imaging (TFMPI) for prediction of significant coronary artery disease (CAD). Methods: 47 patients (PTS) underwent both SPECT-imaging and coronary angiography. TF-MPI was performed in SPECT technique, preceded by bicycle exercise test. Images were analyzed both visually and quantitatively. Results: Significant CAD was found in 27 PTS (57%). 25 of these PTS, showed a defect on their TF-MPI. Sensitivity (SN) is 93% whereas 15 of 20 PTS with smaller CAD (<50% reduction of the vessel) revealed a normal scintigram (specificity (SP) of 75%) . The positive predictive value of this test was 0.83 : whereas the negative predictive value (PV-) was 0.88. The individual coronary arteries (LAD, RCX, RCA) showed a SN of respectively 78%, 17% AND 86% and a SP of 75%, 91% and 61%. Conclusion: TF-MPI seems to be useful in predicting significant CAD. The SN and the PVare high, making this test highly appropriate for the diagnosis of CAD. The diagnostic value of the individual coronary arteries was high. A normal perfusion in the RCX region on the scintigram doesn't exclude the possibility of a significant stenosis. Further research is being performed in a larger group.

Performance of rest redistribution TI-201 SPECT to find out viable myocardium was questioned in that, if we acquire a little later as rest image and aRer 4 hours as redistribution, there were no differences in uptakes between rest and redistribution. By acquiring rest TI-201 SPECT at least 30 minutes after rest injection, could we dispense with redistribution image, or should we maximize differential uptake adopting optimal protocol in rest redistribution TI-201 SPECT? We investigated how we could maximize the difference of rest and delayed T1201 uptakes. Taking 24 hour as latest imaging time, we compared early(l: 15 minutes) and later(II: atter 30 minutes) images and latest(Ill) redistribution of TI-201. Among 34 patients with coronary, artery diseases performing rest/stress/delay SPECT studies, 13 patients showed improvement, 11 aggravated and 10 did not. Among the improved, 1 patient showed early-completed redistribution (1<11=III), 4 patient showed progressive changes (I
I

I

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M O N D A Y P M A P R I L

7

Abstracts Monday afternoon, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

26.19

26.21

ONE-DAY CARDIAC STRESS-REST-SPECT WITH ~9=TeTETROFOSMIN: INFLUENCE OF WASHOUT KINETIC ON REGIONAL MYOCARDIAL UPTAKE IN THE REST STUDY G.Schulz, E.Ostwald, H.J.Kaiser, J.v.Dahl, E.Kleinhans, U. Buell. Aachen University of Technology, Germany The purpose of this study was to evaluate (i) the washout kinetic of 99~l'c-tetrofosmin separated for myocardium with normal and reduced perfusion and (ii) its influence on quantitative analysis in a one-day stress-rest protocol. 20 patients with angiographically proven CAD underwent bicycle exercise stress test with injection of 200 MBq 99'~I'c-tetrofosminand first SPECT 40 min p.i.. 2.3 :k0.4h after the first SPECT a second SPECT was acquired immediately before rest injection of 800 MBq 99~c-tetrofosmin. The rest (third) SPECT was acquired 15 rain later. The relative washout fraction per time (WOFt) was calculated assuming a linear late washout kinetic. 33 regional uptake values, normalised to the perfusion maximum (100 %), were estimated per patient in the exercise SPECT and the rest SPECT, latter both with and without correction of remaining counts from stress injection. In regions with normal perfusiun (uptake >70%) WOFt was i 11.5 :k3.5 °/dh. In regions with severe reduced perfnsion (uptake <50%) WOFt was 8.3 +9.9 %/h. The highest variation of the relative uptake values between rest-SPECT with and without correction of remaining counts from stress injection was 5.4 :k3.5 % in regions with stress induced ischemia. To employ the one-day protocol with a stress-rest activity ratio of 1:4 and an interval of more than 2 h between the examinations a correction by remaining counts from stress injection seems not to be necessary in the quantitative analysis of rest SPECT.

A 360 DEGREE ACQUISITION PROTOCOL DURING TC-99 SESTAMIBI AND SPECT IMPROVES REGIONAL TRACER DISTRIBUTION. L.I.Araujo, J.M.Jimenez-Hoyuela, E.Lin, A.Alavi, J.R. McClellan.University of Pennsylvania, Philadelphia,USA Multiple headed scanners allow acquisition with 360 degree orbit (360) and may result in improved image uniformity. We evaluated regional Tc-99 sestamibi myocardial distribution for 360 with and without iterative (it) reconstruction, were compared with images acquired with a 180-0 orbit (180) in 39 patients (pt) with a < 5% likelihood of CAD. Images obtained during the same acquisition were also corrected for attenuation (AC). All studies were acquired with a Picker 3000 XP scanner obtaining 120 projections every 3 -°. In each pt, 24 ROI's in 3 short axis slices were analyzed. ROI data were normalized to the mean value. [ 180 360 360 it [ AC Ant I 0.90+0.09 0.99+0.08* 1.07+0.09 I 1.02+0.05# Sep I 1.04+0.08 0.98_+0.06* 0.95+0.1 I 1.01+0.08# hff 1 0.92+0.08 0.90-L-_0.06 0.93+0.12 1 0.97+0.06# Lat I 1.10+0.06 1.09+0.07 1.03+0.09 [ 0.96+0.05 180 vs 360, *p<0.001 ; 360 it vs AC # p<0.01 Conclusion 360 with backprojection processing resulted in more uniform regional count distribution in the anterior wall and septum as compared to thel80. 360 with AC and it results in optimal image uniformity.

26.20

26.22

PULMONARY UPTAKE OF 99MTC-TETROFOSMIN IN CORONARY ARTERY DISEASE. CORRELATION WITH LEFT VENTRICULAREJECTIONFRACTION. I Cas~ns, A Ll~cer, J Ciudad. Nuclear Medicine and Cardiology Departments. Hospital Clinico Universitario. Valencia. Spain.

ROC REVEALS D I F F E R E N T R E G I O N A L DIAGNOSTIC U T I L I T I E S O F T H R E E DISPLAY OPTIONS O F 99"Tc-MIBI M Y O C A R D I A L SPECT. T. Leitha, M. Pruckmayer, A. Staudenherz, H. Bailer, M. Gwechenberger, G. Kronik. University Clinic Nuclear Medicine, Vienna; AoKH Krems; AUSTRIA

To stablish the value of 99mTc-tetrofosmin(99mTc-TF) pulmonary uptake in myocardial SPECT to assess left ventricular dysfunction, we have determined a lung to heart ratio (LH) from the unprocessed post-exercise 99mTc-TF SPECT images in a group of 43 coronary patients proven by cardiac catheterization and left ventricular ejection fraction at rest (EF) from equilibrium radionuclide ventriculography, obtained at 24 h of perfusion study. Correlation of LH obtained from a conventional anterior planar image acquired previously of SPECT (0.39!-_0.15)and LH from SPECT (0.40+0.14) in a separate group of 16 patients was r: 0.97(p: 0.0001).In the 43 CAD patients, we have found a significative negative correlation between LH and EF (r:. -0.60, p: 0.0001). The group of patients with EF<40% showed mean LH(0.40_+0.13)significatively higher than patients with EF>~40% (0.29_+0.05) (p: 0.001). Thus, lung uptake of 99mTc-TF as part of routine SPECT, provides assessment of ventricular dysfunction in CAD, similar to that seen with TI-201.

Method: Visual assessment of 99mTC Sestamibi SPECT as three dimensional (3D) perfusion mapping (3D Perfusion/ Motion Map Software), conventional tomographic slices and polar mapping (Cedars-Sinai PTQ) was compared by receiver operating characteristics (ROC) analysis in 392 myocardial segments of 49 CHD patients who underwent symptom limited bicycle stress testing and gated 99mZc sestamibi SPECT. Results: 3D mapping provided the highest diagnostic gain for the detection of severe stenoses above 79%. ROC analysis revealed comparable limitations of all displays in the lateral wall. 3D mapping was further hampered in the proximal anterior wall. Polar mapping appeared to provide a balanced regional performance with an overall satisfactory diagnostic gain, yet inferior global utility. Conclusion: The distinct regional diagnostic utilities of different display options should be considered prior the development of uniform guidelines tbr SPECT documentation.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Monday afternoon, April 7, 1997

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26.23

26.25

DISCRIMINATIVE VALUE OF 201-THALLIUM SPECT LUNG / M Y O C A R D I U M RATIO IN C.AJ3 FOR THREE VESSEL DISEASE AND NORMAL PATIENTS, T. Massardo, M.J. Jolt60 R.Gaiaz, V. Zapata, P. Gonzfilez. Universi b, o f Chile Hospital. Santiago-Chile.

LEFT LATERAL UPRIGHT PROJECTION IN BREAST ATTENUATION-INDUCED ANTERIOR WALL DEFECTS IN WOMEN.

Lung uptake in stress myocardial perfusion images is helpful for recognizing 3 vessel disease (3VD) in balanced CAD. The objective was to evaluate 201-TI SPECT Lung/Myoeardium ratio (L/M) in order to discriminate between patients with 3VD and those with normal coronaries. Twenty patients with 3VD (lesion>50%) and | 5 controls (without lesion) were studied with stress 201TI SPECT (3 mCi; 180°; 32 steps; 40sec). A program was applied using standard areas in row pianar views or voxels in reconstructed tomographic images. There were no LtM difference with sex or stress (dJwridamoie vs exercise). The best ratio was planar anterior view at inferior wall. The mean _+ sd lbr controls was 0.28_+0.06 and for 3VD: 0.48+0.08 (p<[0-6). A control cutoff was selected as the mean + lsd; 93% o f controls and none o f 3VD were under it. Tomographic, anterior or anterolateral wall ratios were less discriminative (p<0.015). Concluding, L/M ratios from row 201 -TI SPECT data are highly discriminative for 3VD, allowing to avoid prior anterior static acquisitions.

R. Petrovici, R. Capalneanu, C. Medrea, G. Coldea. "Niculae Stancioiu" Heart Institute, Cluj-Napoca, Romania. Aim of this study was to find a simple method to differentiate between myocardial pertusion defects caused by ischemia and breast attenuation-induced anterior wall artifacts. We studied 22 women with suspected coronary artery disease (CAD) (atypical chest pain and nondiagnostic exercise°ECG). All patients underwent exercise Tc-99m sestamibi imaging (740 MBq i.v.) in the standard views (anterior, LAO 45 °, and LAO 70°). In all patients anterior wall defects were present. Immediately after the standard acquisition, the patients were studied in the left lateral (LL) upright position, with the thorax touching the collimator, the left arm raised and the hand put on the head. In 20 patients, the anterior wall defects present on the LAO 70 ° were no more visible on the upright LL view. With normal myocardial perfusion in all regions, the scans were considered negative for myocardial ischemia. Three of these 20 patients with normal perfusion underwent coronary angiography, demonstrating normal coronary vessels. In two patients the anterior wall defects in LAO 70 ° were still present in the upright LL view and hemodynamically significant left anterior descending artery stenosis was present at coronary arteriography. These results suggest that LL upright projection allows to differentiate between myocardial ischemia and breast attenuation in women with suspected CAD.

26.24

26.26

STERNAL A I IV.24UATIONOF SEPTALCOUNTS IN MYOCARDIAL SPECTIMAGES. V.Robinson, C.Eubig, J.Corley, S.Raibon, J.Yoder, G.Burke. Medical College of Georgia,Augusta,Georgia,USA.

NEURAL NETWORK APPLIED TO SPECT THALLIUM PERFUSION IMAGING. A Tweddel,G M i d d l e t o n , D G e o g h e g a n , D M c C o r m a c k , B B r o w n , W E v a n s , M F r e n n e a u x , University Hospital a n d University of W a l e s , Cardiff, U n i t e d K i n g d o m ,

Myocardial perfusien abnormalities are assessed by comparison to normal files. The advent of transmission-mapattenuationcorrectionhas changed the usual distribution of radiotracer, in particular, increasing countsin the septal segment. We hypothesizedthat the empiricallynoted decreased septal counts compared with the contralateralwall in normals is due to sternal atten~tion affecting wimarily the inter ventricular septum. W¢ studied 17 patients. 8 males, who had normal perfusionas assessed by two experiemed observexs. Close review of analog images defined flames in which the stemma overlay the septum. Areas of septum with othexidentifiableoverlyingattenuatorswere excluded from analysis. We plotted single flame and ave~'age(multiframe)estimates of septal attenuationfrom analog data vs. the difference, contralateralwall minus septmn(count~ dxel) in the SPECT image. Normalized Septal Attenuation (%)

Single Frame Average all

0.17 ± 0.11 0.10 + 0.10

SPECT

Correlation r = 0.40 p = 0.032 r = 0.46 p = 0.064

frames

Correlation improved if average normalized decrease in septal counts (multipleflames) was multipliedby the numbexof flames showingseptal attenuation r = 0.62 p = 0.008. We conclude I) sternal attenuation may be responsible for the apparent reduced radiotrncer uptake in the septum in normals, 2) the degree of septal attenuation seen on SPECT images depends not only on the severityof attenuation, but alse on the numberof frames that the steraumoverliesthe septmn, 3) these findings will assist in understandingthe new myocardial radiotracer distribution seen in simultaneousatten~tion correctedSPECT.

N e u r o n a l c o m p u t a t i o n a l m e t h o d s t h a t " s i m u l a t e " the brain's decision processes h a v e b e e n applied to i n t e r p r e t a t i o n of thallium perfusion scans. T h e n e u r a l n e t w o r k was t r a i n e d on 8 visually n o r m a l male post stress S P E C T thallium perfusion scans, p r e s e n t e d to the c o m p u t e r as s t a n d a r d p o l a r plots, r e c o n s t r u c t e d from s h o r t axis slices definitely c o n t a i n i n g left v e n t r i c u l a r m y o c a r d i u m . T h e d a t a were encoded b y use of wavelet t r a n s f o r m s , w h i c h p r e s e r v e spatial resolution. T h e n e u r a l n e t w o r k was t h e n tested on 40 scans; a f u r t h e r 8 n o r m a l males, r a n d o m l y mixed w i t h 32 w i t h evidence of myocardial infarction, previously r e p o r t e d as a b n o r m a l . A b n o r m a l was differentiated from n o r m a l in 96%. Site of a b n o r m a l i t y was correctly designated to e i t h e r a n t e r i o r o r infero/lateral in 85%, difficulty arising only in assigning inferior perfusion defects. In s u m m a r y , n e u r a l n e t w o r k s offer potential w h e n applied to t h a l l i u m perfusion scans, a n d m a y be of value as a clinical c o m p u t a t i o n a l aid.

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M O N D A Y P M A P R I L

Abstracts Monday afternoon, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

26.27

26.29

THE FIRST E X P E R I E N C E OF 199TL-DIETHYLDITHIOCARBAMATE USING FOR CEREBRAL AND M Y O C A R D I A L PERFUSION E S T I M A T I O N I.Dygai, I.Shvera, N.Krivonogov, V.Chernov, Yu.Lishmanov Nuclear Medicine Department, Cardiology Institute, Tomsk, Russia.

IS THERE A LINEAR RELATIONSHIP BETWEEN THE HEIGHT/WEIGHT (H/W) RATIO AND THE ANTERIOR/INFERIOR (A/I) MYOCARDIUM COUNT RATIO

The aim o f this study was to evaluate possibility o f 199Tl-diethyldithiocarbamate (199TI-DDC) use for cerebral and myocardial perfusion estimation in pts with combination o f cerebrovasculare disease (CVD) and coronary artery disease (CAD). We studied 12 pts with combination o f CVD and CAD by brain SPECT and myocardial scintigraphy after one i.v. injection o f 199TIDDC. The same pts were investigated by 199T1C1 myocardial imaging.The uptake of 199T1-DDC in brain and myocardium were 5-7% and 2,5-3% o f injected dose, respectively. By all pts cerebral hypoperfusion zones (HZ) corresponding to the regions o f affected artery were obtained. The comparison o f 199TI-DDC and 199TIC1 myocardial imaging results showed identity HZ. 199T1-DDC showed no redistribution phenomenon. Therefore we can't distinguish stable and transient character o f perfusion defects. Thus, 199TI-DDC can be used as agent for simultaneous cerebral and myocardial perfusion estimation.

26.28 THE EVAL UA TION of MYOCARDIAL PERFUSION A F T E R 1NTRA CORONAR Y S T E N T PLA C E M E N T USING Tc-99m TETROFOSM[N S P E C T MYOCARDIAL PERFUSION SCINTIGRAPY A.Boz I B. Karayal~m1, F. Giing~r~, M.Erkdt~, N. De~er21 O. Sancaktar ~. Akdenlz University, Faculty of Medicine, Departments of Nuclear Medicine ~and CardioloD~, Antalya, Turk~'. Coronary stent placement has gained clinical acceptance as a treatment for coronary artery disease. However, there are limited number of reported myocardial perfusion studies on intracoronary stent placement. The aim of this study is to evaluate myocardial perfusion before and after revascularization achieved by intracoronary stent placement. Fifteen patients (2F, 13M, mean age 54_+10 years) were included in this study. Five patients had LAD, 6 RCA and 4 LCx lesions. Same day stress-rest Tc-99m tetrofosmin SPECT myocardial perfusion scintigraphy was performed before (within 1 week) and after (30-40 days) stent placement. In the assessment of SPECT images, segmental visual analysis technique with a five point scoring system was used. Ischemia was detected in 60 out of 300 segments. After revascularization, the number of ischemic segments were significantly reduced and exercise perfusion scores were significantly improved (p<0.001). We concluded that Tc-99m tetrofosmin SPECT myocardial perfusion scintigraphy provides a good documentation of the myocardial peffusion changes at~er intracoronary stent placement.

IN TL-201 CARDIAC SPECT? James J Zhang, Karen Russell, Sung Kim, Charles M Intenzo Dept. of Radiology, Thomas Jefferson University Hospital. Philadelphia, PA 19107 U.S.A. It is known that in the male population there is more attenuation shown in the inferior wall than as opposed to the anterior wall in TI-201 myocardial SPECT. The objective of this study is to determine if a linear relationship exists between the H/W and A/I ratio. A total of 71 male participants (39 with normal coronary artery and 32 with single RCA disease as shown by cardiac catheterization within two weeks of SPECT were enrolled and evaluated. Multiple regression analysis was used to determine if H/W ratio is related to the A/I ratio. Among the normal group A/I ratio was 1.14 (._+0.10), and among the RCA diseased participants the A/I ratio was 1.51(__+0.21). The A/I ratio was significantly different between the two groups (t= -9.7, df=68, p<0.0001). Multiple regression analysis demonstrated a weak relationship between H/W and A/I (R2=0.58) in normal group. The slope of the regression line was -0.05 which does not differ significantly from zero (p=0.048). Data transformations and substitution of the body mass index (BMI kg/m 2) for H/W did not improve the regression model. These data indicate there is no linear relationship between H/W and A/I ratios. The inferior and anteriar walls are attenuated approximately equally in our study regardless of height and weight.

26.41 PROGNOSTIC VALUE OF SYSTOLIC BLOOD PRESSURE MODIFICATIONS

DURING

DOBUTAMINE-ATROPINE

TECHNET1UM-99M SESTAMIBI PERFUSION IMAGING. M.L Geleijnse, R. Rambaldi, A. Elhendy, R.T. van Domburg, A. EM. Reijs, P.M. Fioretti. Thoraxcenter, Rotterdam, The Netherlands. Aim of the study. To assess the clinical and sestamibi perfusion

scintigraphic characteristics of patients with marked dobutamineatropine stress-induced rise and fall in systolic blood pressure (SBP). Methods. A group of 418 patients (age 60 years, 238 men, 203 with previous myocardial infarction) with chest pain underwent a dobutamine-atropine sestarnibi perfusion imaging. Sestamibi scans were scored according to a 6 (extent) x 4 (severity) points model. Marked rise and fall from baseline to peak stress in SBP were defined as an increase of >30 nun Hg and a decrease of >20 nun Hg in SBP, respectively. Hard events were cardiac death (CD), nonfatal myocardial infarction (MI) and hospitalization for congestive heart failure (CHF). Results. During a follow-up of 25 4- 15 months 30 patients had CD, 17 had MI and 8 had CHF. SBP failed in 65 patients (16%) and was associated with older age (p <0.001) and higher baseline SBP (p <0.0001). Sestamibi patterns (whether fixed or reversible) were not associated with a fall in SBP. Cardiac annual event rates were, for patients with and without a fall in SBP, 4.0% vs 3.a% (p=NS) for CD, 6.4% vs. 5.3% (p=NS) for CD/MI and 7.2% vs. a.3% (p=NS) for CD/MI/CHF. SBP rised in 101 patients (24%) and was associated with younger age (p <0.0001), lower baseline ~BP (p <0.005), absence of a history of CI-IF (p <0.02) or ACE-inhibitgr use (p <0.03) and lower fixed perfusion defect scores (p <0.03). Cardiac annual event rates were, for patients with and without a rise in SBP, 2.0% vs 4.0% (p=NS) for CD, 2.7% vs. 6.5% (p <0.02) for CD/MI and 3.5% vs. 7.5% (p <0.02) for CD/MI/CHF. Conclusions. A dobutamine-induced fall in SBP is not associated with sestamibi perfusion defects or adverse prognosis. A rise in SBP, however, is associated with less fixed sestamibi defects and less annual event rates.

Journal of Nuclear Cardiology Volume 4, Number l, Part 2

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26.44

26.42 RIGHT VENTRICULAR FUNCTION AND EXERCISE ABILITY AFTER REPAIR OF TETRALOGY OF FALLOT

L, Labb6,

Abstracts Monday afternoon, April 7, 1997

JL Barat, L. H. Douard, JP Broustet, D.

Ducassou, H6p. Cardiologique, 33604 Pessac, France. Sixty patients (40 males and 20 females, mean age 14+3 years) were evaluated 10+3 years after repair of Tetralogy of Fallot (TF) by exercise test with gas exchange measurement and first-pass radionuclide ventriculography at rest (n=60) and peak exercise (n = 32). The relationship between exercise ability, aerobic capacity and right ventricular (RV) function were determined. Exercise duration, peak oxygen uptake (VO2), ventilatory anaerobic threshold (VAT) and maximal heart-rate were significantly lower in patients (pts) in comparison with 60 normal subjects matched by sex, age and body surface area (p<0.0l). RV ejection fraction (RVEF) was abnormal in 15% of pts (RVEF<40%) and RV adaptation to exercise was altered (RVEF increased by less than 5%) in 50%. The pts with abnormal RVEF at rest had lower peak VO2 and VAT (p<0.01), but RV adaptation to exercise did not correlate with exercise ability or aerobic capacity. However, the pts with RV maladjustment to exercise also had higher respiratory rate (RR) and RR/VCO2 slope than pts with good RV response (respectively 53+9 vs 43_+8 c/rain and 8+4 vs 6+2; p<0.01). After TF repair, systolic RV function at rest but not RVadaptation to exercise limit exercise ability.

99mTc-MIBI IN THE ASSESSMENT OF MYOCARDIAL VIABILITY. SPANISH MULTICENTRIC TRIAL. J. Castell on behalf of the investigators of the multicentric trial. To assess the value of 99mTc-MIBI in the prediction of left ventricular funtional recovery after coronary revascularization, 11 hospitals were involved in a prospective study. 78 patients (59 + 10 years, 12 women) with stable coronary artery disease were studied Three wlews radionuclide engiography and rest 99mTc-MIBI SPECT were performed pre and 3-6 monts after revascularization. Left ventricle was divided in 9 segments for wall motion assessment (visual and Fourier analysis) and for myocardial tracer uptake, that was categorized in 5 ~ovels: (1) 75%-100%, (2) 50%-75%, (3) 40%-50% , (4) 30%-40%, (5) < 30% of maximal myocardial uptake. The 270 (38.5% out of 702) disynergic and revascularized segments were considered for the tracer uptake analysis, There was not diference in mean EF pro and after revase, (41.1 _+14.5% vs 41.8 _+15.7%). EF improved > 5 % in 28% of patients, 101 (37,4%) segments improved contratility. There was significant relation {p O.O1) between myocardial 99mTc-MIBI uptake uptake and segmental functional improvement: MYOCARDIAL U P T A K E SEGMENTAL FUNCTIONAL IMPROVEMENT 75-1OO% 40.6% ns 50-75% 46.1% ns 40-50% 41.3% ns 30-40% 37.7% ns <30% 20.0% p <0.01 Conclusions: A significant number of functional improving segments has been presented with 30-50% uptake. Nevertheles, the positive predictive value of functional recovery of uptake levels over 30% was poor, probably related with the low probability to improve function in the studied population.

26.43

26.45

MYOCARDIAL VIABILITY AND SYSTOLIC FUNCTION OF SYSTEMIC RIGHT VENTRICLE AFTER SENNING OPERATION FOR TRANSPOSITIONOF GREATARTERIES

ISIGNIFICANCE OF PARADOXAL PATTERN IN TECHNETIUM-99m-MIBI SPET IN PATIENTS WITH CORONARYARTERY DISEASE. J, Castell, B. Romero, J. Palet, C. Santana-Boado, J. CandelI-Riera, S. Aguad$, J. Soler-Soler. Hospital General Universitari Vail d'Hebron. Barcelona. Spain. 420 consecutive tecbnetium-99m-MIBI S P E T studies, corresponding to patients (214 without and 206 with previous myocardial infarction) with proved coronary artery disease, were revised in order to know the prevalence and significance of paradoxal pattern (PP) (stress uptake > rest uptake) not attributable to artefact cause. 36/420 patients (8,5%) with PP were detected (19/214 = 9% without and 17/206 = 8% with previous infarction). Only 2 patients had normal coronary angiography. 9 patients had coronary stenosis > 50% of one vessel. 14 of 2 vessels and 11 of 3 vessels. 38 territories with PP were detected: 21 in infero-lateral ilL) region and 17 in antero-septal (AS) region. 5 PP (2 AS and 3 IL) were irrigated by normal coronaries. 28 PP were regions without previous myocardial necrosis and were irrigated by stenosis > 70% in 7, between 50-70% in 7, and < 50% in 14). In 4 of the 7 regions with PP and stenosis > 70% collateral circulation were observed in coronary angiograpby, 5 PP (4 AS and 1 ]L) were regions with previous myocardial necrosis and 4 of these sho wad criteria of myocardial viability (uptake > 40 % in > 50% of territory). We conclude that PP without previous myocardial infarction are observed predominantly (75%) in regions irrigated by coronary arteries without significant stenosis (< 70%), and criteria of myocardial viability is observed in PP of regions with previous myocardial infarction.

L. Labb& JL Barat, H. Douard, D. Ducassou, JP Broustet, HCpital Cardiologique-33604 Pessac (France) After Senning operation for complete transposition of the great arteries (TGA), right ventficular (RV) dysfunction is often described. Pre or post-operative myocardial damage due to hypoxemia has been suspected. To detect abnormalities of RV viability and their relationship with RV function, we studied 42 asymptomatic patients (pts) (9 girls, 33 boys), 12.3+4 years after Senning correction. The mean age at surgery was 6.4+5 months• All pts performed myocardial tomoscintigraphy at rest, • 1 hour after injection of 1.5 mCi of Thallium 201. RV ejection fraction (RVEF) was measured by first-pass radionuclide ventriculography (99roTe) at rest and at maximal exercise in the supine position. We found myocardial viability abnormalities of the systemic RV in 18/42 pts (43%) : moderate in 12 pts and severe in 6 pts. Resting RVEF and maximal end-exercise RVEF were significantly lower in pts with myocardial defects (respectively 45+5 % VS 49!-_7% and 48+9% VS 58+9% ; p<0.05). Conclusion : after Senning operation for TGA, myocardial defects of the systemic RV are frequent, and are associated with altered systolic RV function at rest and at peak-exercise.

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M O N D A Y

P M A P R I L 7

Abstracts Monday afternoon, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

26.46

26.48

R I G H T AND LEFT V E N T R I C U L A R F U N C T I O N IN R E P A I R E D TETRALOGY OF FALLOT G. Manfredini, P. Bertolaccini, R. Lorenzoni, A. Maneschi. Nuclear Medicine Department, Massa Hospital, Italy

DOES COMBINATION OF PHYSICAL AND MENTAL STRESS IMPROVE ISCHEMIA DETECTION ?

We aimed to evaluate right and left ventricular (RV and LV) fnnction in 22 asymptomatic adult patients (pts; 17 males, mean age 23 [ 1.9-271 years) with repaired tetralogy of Fallot (TF). Methods. RV and LV ejection fraction (EF, %, mean [range]) were measured at rest and at maximal exercise by equilibrium radionuclide ventriculography (normal values: rest, RVEF _>40, LVEF > 50; exercise, >_5 increment). A i pulmonary scintigraphy was also performed in 16/22 pts. Results. At rest, RVEF (46 140-581) and LVEF (60 [50-i 68]) were normal in all pts. Stress RVEF (46 130-601) was: abnormal in 1.5/22 pts, while stress LVEF (68 158-781) was: abnormal in 3/22 pts. No differences were found in rest andi stress RVEF and LVEF between pts who had and had not a': palliative operation before correction, which were operated before and after 5 years of age, and which had and had not a transannular patch inserted. Pts with severe pulmonary' regurgitation (8/22)had lower stress RVEF (41_+7 vs 49_+5; p
Christoph Gradel, Patrick R. Hunziker, Jan MLiller Brand, Matthias Pfisterer, University Hospital, Basel, Switzerland In some patients with typical angina ischemia is not detected by conventional exercise testing. To test if a combination of physical and mental stress improves diagnosis of ischemia 10 patients withproven coronary artery disease (CAD) and 11 controls underwent radionuclide angiography at rest and during mental arithmetics (MA), supinebicycle exercise (EX) and a combination of both (COMB) in randomized order. A decrease in LVEF was usea as criterium ' for ischemia. Results: (see graph and table)

od II +~ ~T~

Detection of CAD:

• CAD • Control

MA EX COMB

Sens%: 50 p:NS p:O.03

°t

:O.OOZ

70

80

Spec%: 82

73

91

Acc%: 67

71

86

Stress: MA EX COMB Discrimination of patients with CAD from control subjects by the change in LVEF and diagnostic accuracy was best with COMB. The mean maximal rate pressure product was s~milarduring EX and COMB(24833 vs 25398, p=NS). t;onclusion: Detection of ischemia Dy mnctional testing may be improved by the combination of. physical and mental stress. This improvement is not due to a increase in oxygen demand by the addition of mental stress.

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26.49

l o d i n e - 1 2 3 - B M I P P SPECT IS USEFUL FOR DETECTING M Y O C A R D I A L D A M A G E AND FOLLOW-UP OF PATIENTS WITH VASOSPASTIC ANGINA Y.Arai, S. Mizuno, M. Ohnaka, and K Yamamoto*. Fukui Cardiovascular Center and Fukui Medical School *, Fukui, Japan

MENTAL STRESS INDUCE PERFUSION DEFECTS IN PATIENTS WITH POSITIVE STRESS THALLIUM 201 SCINTIGRAPHY. A. ALLAM, M. ABDELHADY, A.MATWAA, S. SHIAKIR, M.FARID, M. SALAMA, I. SHAWKY. AL AZHAR UNI, EGYPT.

Coronary spasm may produce profund and prolonged myocardial ischemia. In such circumstances, oxidation of free fatty acids is greatly suppressed and glucose metabolism plays a major role for residual oxidative metabolism. Thus alternation of fatty acid oxidation is considered to be a sensitive marker of ischemia. Iodine123- BMIPP has been proposed as a new tracer of cardiac free fatty acid metabolism.We tested that lodine-123BMIPP SPECT(BM-S) could detect myocardial damage in patients(pts) with vasospastic angina(VSA) and BM-S could be used in follow-up of pts with VSA. We examined 42 VSA pts(33 male,61_+8 yr') without organic coronary stenosis. Serial 180° SPECT images were obtained starting 20 minutes after injection of 3 mCi of BMIPP at rest. BM-S showed regional low radioactivity in 34 pts (81.0%). With complete or partial agreement between the BM-S abnormality and spasm induced coronary territory seen in 31 pts (71%). In the repeat BMIPP study (n=20) during the follow-up period (average 190 days), in 14pts, BM-S obtained after VSA attacks had disappeared showed improvement. The other 6 pts with increases in VSA attacks showed deteriorated tracer uptake on BM-S. BMIPP can detect myocardial damage with VSA and may be useful for follow-up of pts with VSA in monitoring response to treatment.

Twenty five patients (pts) with positive physical stress (PhS) thallium -201(T1) scintigraphy underwent mental stress (MS) T1. 24/25 pts were males, mean age 50.9 + 8.2 years, 18/25 pts had previous MI, 21/25 had history of chest pain (CP) and 22/25 had resting ECG abnomaalities. 15/25 pts had ST segment depression with PhS and 3/25 with MS P < .001, CP was experienced by 14/25 with PhS and 6/25 with MS p < .001. Total number perfusion defect (PD) (mean + SD ) 8.5 + 2.3 PhS and 6.8 + 2.4 MS P < .003, reversible ( RV ) PD 4.2 + 2.2 PhS and 1.7 _+1.7 MS P < .003, partially RV PD 3.2 + 2.3 PhS and 2.0 + 1.9 MS P < .02, Fixed PD 1.0 _+1.3 PhS and 3.1 +2.7 MSP<.001 .RVindex8.2 + 3.3 PhS and 4.16 + 2.4 MS P<.001. 24/25 pts ( 95 % ) had RV PD on MS TI, of these 5/25 (20%) had more RV PD with MS than with PhS. of 187 RV segments on PhS TI only 70 (37 % ) were RV on MS TI. Thus, most pts with PhS induced ischaemia develop ischaemia when subjected to MS. However, MS induced ischaemia is less in extent and severity. MS induced ischaemia is less accompained with CP and ST depression.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

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26.52

26.50 DEFT

Abstracts Monday afternoon, April 7, 1997

VENTRICLE DYSFUNCTION IN PATIENTS

R E C E I V I N G PACL1TAXEL. R.A. Vaid6s Olmos, W.W. ten Bokkcl Huinink, C.A. Hoefnagel. The Netherlands Cancer Institute, Amsterdam.

INFLUENCE OF THYROID DISORDERS ON CARDIAC SYMPATHETIC NERVE FUNCTION M.Nakamura, K.Mizoguchi, S, Yasuda, T.Mocbizuki, S.Koide Chigasaki Municipal Hospital, Kanagawa, Japan

Over the last years, paclitaxel, an effective antineoplastic agent, has been incorporated in the treatment o f advanced and refractory breast cancer. A[thongh transient cardiac rhythm disturbances have been described during or shortly after drug infusion, cardiac effects between drug courses or in the post-therapy period have not been documented. In this paper, we report an abnormal left ventricle ejection fraction (LVEF) decrease (10% or more to a EF-level below 50%) in 6 patients (age 44-67 years) treated with paclitaxel for advanced breast carcinoma: in 3 patients, without previous chemotherapy but with internal mammary lymph node chain irradiation 3-18 years previously, LVEF-decrease was observed 1-6 months after paclitaxel administration (dose range 525-1225 mg/mZ), ahd in 3 patients with doxorubicin refractory disease LVEF decreased when paclitaxel (dose range 350-875 mg/m -~) was administered 1-5 months after doxorubicin (dose range 420-530 mghn2); IIqn-antimyosin scan, used to document doxorub[cin-related myocyte damage, showed intense cardiac uptake in 1 case. These findings suggest that paclitaxel may induce left velm'icle dysfunction. LVEF monitoring is specially recommended in patients previously treated with anthracyclines and thoracic irradiation including the heart.

Thyroid hormone has direct inotropic and chronotropic effects on the heart. Thyroid diseases produce significant alternations in cardiac function. The cardiac sympathetic nerve (CSN) function was evaluated in 11 patients (pts) with hyperthyroidism (HPR; FT4 6.4"+'2.6ng/dl), 5 pts with hypothroidism (HPO; FT4 0.5-1-0.2ng/dl) and 12 control subjects (FT4 1.2-1-O.2ng/dl} using with I-123 metaiodobenzylguanidine (MIBG} myocardial scintigraphy. Planar images were obtained in anterior position 15 minutes (initial images} and 4 hours (delayed images)after injection of 111 MBq 1-123 MIBG. Image quantitation was based on the ratio of myocardial to mediastinal I-123 MIBG uptake (H/M) and the percentwashout from initial to delayed images. Plasma norepinephrine (NE) and fractional shortening of left ventricle (%FS) by echocardiography were determined. Results delayed H/M washout(%) NE (ng/ml) %FS HPR 1.76_4-0.23"* 34.7___16.7 0.29-1-0.17 33,8___11.3 Cotrol 2.14-{-0.11 31,6-1-5.7 0.43___0.19 33.7"4-3.4 HPO 2,48__.0.62* 32.2_14.5 0,51___0.25 32.2___5.4 ( ** p< 0.01, * p< 0.05 compared to controls) There was negative colleration between the delayed H/M ratio and the FT4 concentration ( r = -0.54, p( 0.01 }. Conclusion The CSN function shown by the MIBG uptake is decreased in HPR and increased in HPO. The CSN helps the heart ajust to pathophysiologic changes by the thyroid hormone.

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26.53

DIAGNOSIS OF TRANSPLANT (~ORONARY ARTERY DISEASE (TCAD): STRESS 9~"Tc-TETROFOSMIN SPECT. O.Vegazo, R.Mufioz, P. Madariaga, J.A. Garcia Robles, C. Trampal, I. Almoguera, P. D o m i n g u e z , J.M. P6rez Vazquez. Hospital Gregorio Marafion. Madrid. Spain. Heart t r a n s p l a n t a t i o n is an accepted treatment of end-stage heart disease. With i m p r o v e m e n t in the treatment of infection and rejection, TCAD is the lead cause of late mortality in cardiac t r a n s p l a n t patients (CTP). The aim of this study was to investigate the usefulness of treadmill exercise 99mTc-TetrofosminSpect in the diagnosis and localization of TCAD. We studied 30 CTP (27 men, mean age 54.2 + 2.2 yrs), with mean survival 28.2 _+ 4.7 months p o s t - t r a u s p l a n t a t i o n . Coronary angiography, defined as the reference technique for the global and territorial evaluation of myocardial Spect, was p e r f o r m e d within 2 months prior to or after the Spect study (mean 54.9 + 8.2 days). The sensitivity, specificity and predictive accuracy for detection of TCAD were calculated. Kappa statistical values was also calculated. SPECT Overall TCAD TCAI)-DA TCAD-CX TCAD-CD Sensitivity(%) 91 43 29 70 Specificity(%) 6g 64 g4 g5 VI'P(%) 63 30 33 70 VPN(%) 93 80 79 85 Accuracy.(%) 77 63 70 80 Kappa 0.5415 0.1081 0.1176 0.5500 p value 0.0017 0.5416 0.5173 0.0026 In conclusion: treadmill exercise 99"Tc-Tetrofosmin cardiac Spect is an efficient alternative n o n - i n v a s i v e technique in the global detection of TCAD. The negative predictive value is very high (VPN=93%). For this reason a normal myocardial perfusion after a cardiac Spect could avoid the coronary arteriography.

5-FLUOROURACIL (5-FU) CARDIOTOXICITY DETECTED BY DIPYRIDAMOLE THALLIUM-201 CARDIAC IMAGING T. Bishiniotis, G. Katseas, G. Pentheroudakis, N. Salem, G. Koutsibanis, A. Litos, D. Mouratidou, D. Hatseras. Theagenion Anticancer Hospital, Thessaloniki, Macedonia, Greece. 5-FU acute cardiotoxicity is frequent (12.5%) and its clinical manifestations include all forms of myocardial ischemia, cardiogenic shock and sudden cardiac death. The aim of this study was to investigate the effect of the drug in the coronary blood flow. 45 patients (M/F:39/6, mean age:59 years) with advanced head and neck cancer and normal cardiac function were included prospectively in a chemotherapeutic protocol with continuous IV infusion of 5-FU 1000mg/m2/day for 5 consecutive days. The evaluation of the myocardial perfusion was based on dipyridamole thallium-201 cardiac imaging and included 2 scans for every patient : (1) a dipyridamole thallium-201 heart scan before the initiation af chemotherapy, and (2) after one month, using the same imaging protocol and the same doses of dipyridamole and thallium-201, a heart scan while the patient was under the continuous IV infusion of 5-FU (3rd-4th day). The comparison of the 2 scans and the quantification of the results were based on the computer programme of the University of Alabama. There was a statistically significant decrease in the myocardial thallium-201 uptake during the IV 5-FU infusion (p<0.001). This decrease was equivalent to 24.5% and concerned equally all myocardial segments. Conclusion: 5-FU infusion results in great reduction (24.5%) of the myocardial thallium-201 uptake under pharmacologic vasodilation. This effect superimposed on preexisting coronary obstructions could explain the acute cardiotoxic effect of this chemotherapeutic agent.

N C A ¥ P IV A P B I L 7

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Abstracts Monday afternoon, April 7, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

26.54

26.56

ANTIMYOSIN SClNTIGRAPHY IS USEFUL FOR DETECTING CARDIACAMYLOIDOSlS.

%SYSTOLIC WALL THICKENING (%SWT). RESULT IN NORMAL SUBJECTS. A Sandrin, V Arja, J Neuburger, C Serra, V Balestrini. Instituto Modelo de Cardiologia, FUCCADIM, C6rdoba, Argentina.

J. Lekakis, M.A. Dimopoulos, J. Nanas, V. Prassopoulos, N. Agapitos, G. Alexopoulos, S. Stamatelopoulos, S. Moulopoulos, P. Kostamis. 'Alexandra" University Hospital, Athens, Greece. Cardiac amyloidosis belongs to the list of great cardiac masqueraders. To examine the usefulness of antimyosin scintigraphy in cietecting cardiac amyloidosis, we studied 7 patients (pts) with primary or myeloma-related amyloidosis 13 women, 4 men, age 56±9 yrs) and myocardial amyloid infiltration proved by endomyocardial biopsy. Six subjects with tow probability for amyloidosis and left ventricular Iwpertrophy due to hypertension were used as controls. Lef: ventricular thickness was comparable in tots and ton'trois. A heart to lung (H/L) ratio was used to quantify tracer uptake. Control subject had normal antimyosin study (H/L<1.6, mean 1.43±0.1L Pts with cardiac amyloidosis preset]ted abnormal scan (H/L 2.1 to 3.2, mean 2.5±0.4, p
Tc-99m-MIBI images allow simultaneous assessment of perfusion-function. %SWT appears as a useful tool to assess LV function. Objective: assess %$WT LV regional pattern in normal subjects. Matedal:in 15 normal volunteers (9 men, 5 women), Age X 38 (25-54) with low probability of coronary disease, we performed rest-gated-SPECT with Tc-99mSestamibi-25mci using 8 frames/cardiac cycle. Then, 2 slices were chosen in short axis for gated analysis (mid-apical and mid-basal), each was divided in 4 segments (S): Ant (A), Septal (Se),lnfedor (I), lateral (La) and one slice in long axis (one S: Apex).With total counts/S we performed time-activity curves/S. Then, we obtained ES counts and ED counts for each S and calculated %SWT: ES eounts-ED counts/ED count x 100%. Results: Apex Apical Basal A $e I [La A $e I [La =(%SVVT 51 28 31 30 16 25 21 19 23 %SVVT 51 26 22 I_ p<0.0001 _1 ]__ p<0.O001 __1 P p<0.0001 I Conclusion: 1-Assessment of %SWT in normal subjects showed heterogeneity among the different myocardial S, as well as among LV apical and basal areas. 2-Maximal %SWT was obtained in Apex (x 51%) and minimum, in the lateroapical $ (x 16%).

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1-123 MIBG MYOCARDIAL SPECT IN PATIENTS WITH DIABETES MELLITUS TYPE II; COMPARATIVE STUDY WITH VERSUS WITHOUT SILENT MYOCARDIAL ISCHEMIA S.Nagamachi,S.Jinnouchi,Leo G. Flores II,K.Watanabe, T. Kurose, S.Matsukura, Miyzaki Medical College, Miyazaki, JAPAN

ONLY SCINTIGRAPHY CAN RELIABLY DETECT MYOCARDIAL DANL~GE DUE TO ELECTRICAL BURN. H. Iino: T. Kamada, H. Nohara, M. Matsumoto, I. Harada, Y Kobayashi, Y Nagai, C. Ibukiyama, H. Matsumura, K .Watanabe, Tokyo Medical College, Tokyo, Japan.

Cardiac autonomic nerve dysfunction is important complication of diabetis mellitus ( NIDDM ). This study was undertaken to assess the effect of silent myocardial ischemia in the cardiac sympathetic innervation of NIDDM by using 1-123 MIBG myocardial SPECT. The study was done in 10 normal subjects and 50 NIDDM patients. Tracer uptake was evaluated visually by dividing myocardium into 20 segments. Silent myocardial ischemia was defined as the presence of a reversible perfusion defect on TI-201 myocardial SPECT. Mean value of visual uptake score of each segments were compared between normal control, NIDDM without silent ischemia [I(-),n=26] and NIDDM with silent ischemia [I(+),n=24]. Total uptake score were significantly lower in I(+) group than I(-) group. Silent myocardial ischemia aggravates cardiac autonomic nerve dysfunction in diabetic patients.

Seven patients (pts) with electrical injury were evaluated b y electrocardiography (ECG), ultrasound cardiography, coronary arteriography (CAG), T1-SPECT and I- 123 Metaiedobenzylguanidine (MIBG) SPECT as well as CK-MB levels. The ECG abnormalities were transient. The CK-MB levels, which did not reflect myocardial damage, increased in 2 pts. Most pts showed normal wall motion except for 2 with mild hypokinesis in the anterior wall. All 5 pts who underwent CAG demonstrated normal findings with neither stenosis nor thrombi. T1-SPECT revealed myocardial damage in a[~ pts and MIBG-SPECT showed abnormal accumulation in 5 of the 6 pts examine& The myocardial damage was often found in the anteroseptal wall. The decreased accumulation was more notable in TI-SPECT than MIBG, indicating that the sympathetic nerve system was less damaged than myocardium. TI-SPECT and MIBG-SPECT are the most effective methods to detect myocardial damage, which is often not found by other examinations.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Tuesday morning, April 8, 1997

26.58

Tuesday AM, April 8, 1997

IDENTIFICATION OF SMALL MYOCARDIAL INJURY BY Tc-99m PYROPHOSPHATE SPECT IN PATIENTS UNDERGOING RADIOFREQUENCYABLATION OF ARRHYTHMIA ItS Born,JG Cho, HC Song, JJ Min,JY Kim, JC Kang. ChonnamUniversityHospital,Kwangju,KOREA

Sessions 41, 46, and 49-53

ttadiofrcqueney (RF) inducessmall circumscribedmyocardialdamage, and is now most commonlyused for ablationof arrhythmi~ The aim of this study was to demonstratethe ability of Te-99m pymphosphate (PYP) imaging to detect small myocardial lesionsproducedby RF in patients (lots)undergoingRF ablationof arrhythmia(RFA). Eleven arrhythmiepts (8 males and 3 females,mean age 41) were examinedtwo days after RFA. Numbersof RF applicationswere9.6* 8.5 (range 2-24). Planar and SPECT imagingswere dane 2 hours after an intravenousinjectionof 740 MBq of PYP. Tomogra~ic data were acquired over 360 degrees with a rotating singleheaded gammacamera. Sixty four la'ojecliouswere obtained,in a 64x64 matrix for 20 see per image. F~tered back projection was performed with a Hamming-Harm filter. The clearlydistinguishablemyocardialhot uptake was regarded as positive finding. Among 11 pts 8 (7Z7%) showed positiveuptakes in ablationsites on SPECT images, while none shown positive uptake on planar images, RFA sites in three pts failed to be visualized. No correlation of intensityof uptakes with numbersof RF applicationswas noted. We conclude that PYP SPFL'T could be used to evaluate the site and extent of small myocardialinjuriesproducedby RE

J. Narula, D. Elmaleh, A. Petmv, J. Babich, A.J. Fischman, B.A. Khaw. Massachusetts General Hospital, and Northeastern University, Boston, MA, USA

$43

41.1 TARGETING PROLIFERATING SMOOTH MUSCLE CELL PHENOTYPE FOR NONINVASIVE LOCALIZATION OF EXPERIMENTAL ATHEROSCLEROTIC LESIONS

A chimedc mouse/human antibody Z2D3 as well as diadenosine tetraphosphate (Ap4A) have been used to target the phenotypic change or receptor upregulartion, respectively. These two targeting strategies were compared in 12 NZW rabbits. In 6 rabbits experimental athemsclemtic lesions were induced by abdominal aorta deendothelialization and hyperlipidemic diet for 12 weeks and 6 rabbits were used as normal controls. Z2D3 F(ab')2 (50p.g, 650gCi) or 99r"Tc-Ap4A (2 mCi) was administered i.v. to 3 atherosclerotic and 3 control animals. Gamma imaging was performed up to 48 h in Z2D3 and 3 h in Ap4A group. All lesions were visualized by 24 h with Z2D3 and within one-half hour by Ap4A. No uptake was seen in the control animals. The aorta were removed, imaged ex vivo and gamma well-counted for quantitative assessment. Tracer Mean % Injected Dose/Gram Lesion/Normal Lesion Normal t111n-Z2D3 0.084-0.02 0.02+0.002 4.9 99n'q'c-Ap4A 0.08+0.01 0.014.0.004 7.4 This study demonstrates feasibility of imaging atherosclerotic lesions and suggests that while antibody-based technology provides specificity to the imaging procedure, small molecular weight radiopharmaceuticals enable quick target visualization.

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SPECIFIC MYOCARDIAL INVOLVEMENT IN SYSTEMIC DISEASES ASSESSED BY INDIUM111-ANTIMYOSINANTIBODY (AMA) AND REST THALLIUM SPECT. L. Sarda, M. Faraggi, R. Lebtahi, D. Daou, E. Palazzo, M.F. Kahn, D. Le Guludec. Bichat Hospital. Nuclear medicine department. Pads. France.

IMPROVED MID-TERM SURVIVAL AND FUNCTIONAL STATUS AFTER CABG IN PATIENTS WITH CONGESTIV HEART FAILURE SELECTED FOR REVASCULARIZATION BASED ON VIABILITY ASSESSMENT F. Haas, C. Haehnel, C. Duvernoy, W. Picker, S. Nekolla, S. Martinoff, H. Meisner, M. Schwaiger. German Heart Centre Munich, Germany Recent studies have shown that the magnitude of improvement in heart failure symptoms after CABG is related to the extent and magnitude of myocardial viability. This study evaluated the "m)-pact of the extent of tissueviability 9 n short- and mid-term-survival and on global tunctional improvement after CABG. Thus far, we have studied 84patients (pts) with advanced 3-vessel-disease and marked- LV-dysganction who underwent CABG. Of these pts, 43 were selected based on clinical status and angiographic data (group A) while 41 also underwent PET-imaging (group B). Patients of both groups showed no difference m preoperative clinical charcteristics and demographics. Early-postoperatively, 14% of group A developed a low output syndrome, while only-2.4% of group B (0=0.05). Grouo A showed a hospital mortality of I t . 6 % ; there was no [n-hospital mortality in group B (p=0.02). After two years the survival was 59% m group A, however, 97.5% ifi group B (p=0.003). Left ventncul~ ejection fraction (EF) of group A, assessed after one _~ear by radionuclide ventriculdgraph¥, increased from 29.8_3.9 to 34.3+12~,4 [AEF 16;6°~, (~.s)]. However, the mean EF or group t~ maprovea sigmtacantly from 26.2_+4.1% to 34.8_+12.4% [AEF 36.2%, 0=0.003]. The results suggest that PET imaging in pts with severe LV-dysfunction ~I'oes not.only predict Iongterm benefit, but can illso be used for permperatave risk assessment.

The diagnosis of myocardial injury related to systemic diseases is difficult, but clinically relevant because of a poor prognosis. 25 pts with various systemic disorders were investigated and classified in 2 groups according to the presence (G1, n=12) or the absence (G2, n=13) of LV dysfunction. Planar images were obtained 48h after injection of In111-AMA (92 MBq). Then, dual isotope In/T] rest SPECT was performed. Results: 9/12 G1 pts showed a significant diffuse LV AMA uptake, with homogeneous TI (n=6), or small segmental TI defect (n=3). These 2 types of TI and AMA mismatch patterns did not argue for recent myocardial infarction due to coronary artery occlusion. 3/12 G1 pts and 12/13 G2 pts had negative AMA scan with homogeneous TI scan. One G2 pt showed diffuse intense LV AMA uptake and normal TI scan. Conclusion: dual isotope TI/In myocardial imaging is useful for the detection of myocardial involvement related to systemic diseases, and may be helpful for the differential diagnosis of myocardial infarction due to coronary artery occlusion.

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Abstracts Tuesday morning, April 8, 1997

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41.5

ATTENUATION CORRECTED TETROFOSMIN SPECT FOR DETECTION OF VIABLE MYOCARDIUM: COMPARISON WITH FDG-PET I. Matsunari, G. B6ning, S. Ziegler, S. Nekolla, J. Stolfuss, J. Schneider-Eicke, I. Kosa, E. Ficaro, M. Schwaiger. Technische

ADENOSINE SPECT TO ASSESS ANTI-ISCHEMIC D R U G THERAPY vs C O R O N A R Y REVASCULARIZATION FOLLOWING ACUTE MYOCARDIAL INFARCTION: A PROSPECTIVE RANDOMIZED TRIAL. Habib A. Dakik, Mario S. Verani, Zuo-Xiang He, John J. Mahmarian. Baylor College o f Medicine, Houston, Tx U S A

Universitgit Miinchen, Germany

T U E S D A Y

Journal of Nuclear Cardiology January/February 1997, Part 2

The role of 99~To-labeled perfuston tracers for assessing myocardial viability remains controversial. Attenuation artifacts affect the diagnostic accuracy of SPECT ima~,es. We assessed the efficacy of attenuation corrected (AC) "~I'c-tetrofosmin (TFM) SPECT in identifying viable myocardium compared to FDG-PET. 24 patients with coronary artery disease (mean LVEF 30%) underwent resting TFM SPECT and FDG-PET. Segments with a normalized FDG uptake >70% were defined as viable; segments with a FDG uptake <50% were defined as scar; and segments with a FDG uptake 50-70% were defined as intermediate. 12 of 49 segments (24%) with TFM defects (<50% of peak) on the non-attenuation corrected (NC) images were viable compared to only 1 of 33 segments (3%) on the AC images (P<.01). Using a threshold cutoff of 50% of peak as an index of viability for TFM SPECT, misinterpretation of viability (either PET viable as non-viable or PET scar as viable) occured in only 2 segments on the AC images, as compared to 17 segments on the NC images. On patient-by-patient basis, 9 of 24 patients (38%) had viable segments within TFM defects on the NC images, compared to only l (4%) on the AC images (P=.01). The results indicate that AC resting TFM SPECT correctly discriminates viable from scarred myocardium with only a few errors in interpretation. Further work should aim for the incorporation of scatter correction combined with attenuation correction.

We evaluated a strategy o f medical therapy (MT) vs coronary revascularization (CR) for reducing myocardial ischemia in 42 stable pts who had adenosine TI-20I SPECT 4.54-2.9 days after acute infarction. After randomization to MT (N=22) or CR (N=20), SPECT was repeated at 424-26 days. The baseline total and ischemic perfusion defect sizes (PDS) were similar between MT (384-13%, 224-12%) and CR (36=}=12%, 19~7%). A significant (p<.0001) yet similar decrease in total (-124-11% vs -164-15%) and ischemic (-12 4-10% vs -134-10%) PDS was observed with MT and CR, respectively. Seven pts (4 MT, 3 CR) had a cardiac event at 94-5 months. The ischemic PDS decreased more in the 35 pts without (-13.9%) vs the 7 pts with (-4.9%) a cardiac event (p=.01). In fact, pts who decreased their total PDS by >9% had a markedly lower event rate (4%) compared to those who decreased it by <9% (35%) (p<.0l). Conclusions: Intensive MT reduces myocardial ischemia to a similar extent as CR. The change in PDS following either MT or CR predicts subsequent cardiac events.

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41.6

CORRELATION OF FATTY ACID METABOLISM AND CONTRACTILE RESERVE ASSESSED BY BMIPP SPECT AND POSTEXTRASYSTOLIC POTENTIATION IN ACUTE MYOCARDIAL INFARCTION. A. Hashimoto, T. Nakata, H. Kobayashi, K. Tsuehihashi, K. Shimamoto. Sapporo Medical University, Sapporo, Japan.

ACUTE ISCHEMIC LEFT VENTRICULAR DYSFUNCTION ALTERS CORONARY FLOW RESERVE IN REMOTE NONISCHEMIC REGION Edouard Daher, Donald P. Dione, Eliot Heller, Paul DeMan, Michael Shen, Jennifer Hu, Albert J. Sinusas. Yale University, New Haven, CT, USA Impaired coronary, flow reserv e (CFR) has been noted in nonischemie (NIl region remote fi'om myocardial infarction (INF) in absence of CAD, and attributed to microvascular disease. To determine if impairment in remote CFR is caused by a mechanical disadvantage (MD) associated with ischenfic dysfunction, we evaluated changes in regional phasic flow and thickening(TF) in presence of distal(DI) and proximal (PX) LAD occlusion (OCC) in 7 open chest dogs. Doppler flow probes were placed on LAD and LCX. Doppler TF probes were placed in INF and NI regions. CFR was assessed by intracoronary injection of adenosine (36~tg). INF area (%LV) was defined by regions with endocardial microsphere flow below 0.3 ml/min/gm. Heart rate and aortic pressure remained stable (p=ns).(p<.05 vs * Basetil~e. ^DI OCC) Baseline DI OCC PX OCC INF ~u:ea %LV --12_+1 30+2 ^ LAD %TF 1.8_+1 -8+ 1* -4+ 1* LCX %TF 10.7_+1.8 12.8+2.4 14.9_+2.8" LCX CFR 2.15_+0.29 1.71 +0.17" 1.48+0.13" NI thickening increased progressively in response to the extent of INF, placing the NI region at a MD. There was a progressive decline in NI CFR. Thus, a mechanical mechanism may explain the alterations in NI CFR during INF and results in reduction of inducible flow heterogeneity.

To investigate contractile reserve in metabolically depressed myocardium, SPECT with thallium and fl -methyl fatty acid, BMIPP, was performed in 32 patients with acute myocardial infarction, including 26 patients undergoing primary coronary angioplasty. The activities of thallium and BMIPP were quantified as a severity score ( SS ) and compared with regional wall motion abnormality ( R W A ) and response to programmed postextrasystolic potentiation ( PESP ) quantified using a eenterline technique and contrast left ventriculography. BMIPPSS was significantly greater than TI-SS ( 85 +-- 66 vs 74 -- 53, P<0.05 ) . PESP significantly improved RWA compared to at a control rhythm ( 80 -- 24 vs 121 +-- 49, P<0.001 ) . The degree of response to PESP (A RWA ) at an acute phase of infarction was significantly (P<0.05) related to improved RWA during followup (y=0.56x+5.50, r=0.56 ) and to the mismatched activity (A SS ) between thal]ium and BMIPP (y=0.78x+32.07, r=0.52 ) which in turn closely correlated with improved RWA during followup (y=l.08x+15.68, r=0.73 ) . In conclusion, metabolically depressed but viable myocardium identified by SPECT with thallium and BMIPP has contractile reserve assessed by PESP, has possible future recovery of myocardial contractility, and suggests the presence of stunning phenomenon in patients with acute myocardial infarction.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Tuesday morning, April 8, 1997

41.7

46.2

MYOCARDIAL PRE- AND POSTSYNAPTIC AUTONOMIC DYSFUNCTION IN HYPERTROPHIC CARDIOMYOPATHY. M.A. Sch~fers, D. Dutka, C.G. Rhodes, A.A. Lammerl:sma, F. HelTnannsen, O. Schober, P.G. Camici. MRC Cyclotron Unit, Hammersmith Hospital, London, UK. BACKGROUND AND AIM. Despite the genetic determination of! hypertrophic cardiomyopathy (HCM), several factors including! autonomic dysfunction also play a role in the phenotypic expression. A recent study using positron emission tomography (PET) demonstrated that postsynaptic J~adranoceptor density (J~AR) is reduced in patients suffedng from HCM and is correlated with the disease progression. The aim of the present study was to ascertain whether alterations in presynaptic catecholamine re-uptake (uptake-I) is associated with postsynaptic I3AR downregulation.

PAIRED COMPARISONOF A NEW Te99m-HUMANSERUM ALBUMIN(ItSA) ANDTe99m-LABELEDRED BLOODCELLS (RBC) FOR RADIONUCLIDEANGIOGRAPHY(I~A). A.S. Hamb~e, R.Vandermeiren, E.Joosens, K.Verbeke, A.Verbruggen, M.De Roo. Middelheim Hospital,Antwerp,Belgium.

METHODS. A group of sixteen HCM patients (mean age 42.1 -J- 14.0 yr) was studied with PET. The efficiency of the presynaptic sympathetic re-uptake was measured by the VD for carbon-11 labelled hydroxyephedrine (HED) in 9/16 patients. In 13/16 patients Bmaxfor pAR was derived from a C-11-CGP 12177 (CGP) scan. In 6/16 patients we performed both studies. Patient data were compared with those found in age matched groups of normal controls (CGP: n=20, mean age 43.5 + 15.5 yr, HED: n=10, mean age 34.5 + 8.3 yr). RESULTS. We found significantly lower global mean Vo for HED in HCM patients (33.4 + 14.3 ml/g tissue) compared to controls (71.0 + 18.8 ml/g tissue, p < 0.001). Global mean myocardial pAR was significantly reduced in HCM patients (7.3 + 2.6 pmol/g tissue) compared to controls (10.2 ± 2.9 pmol/g tissue, p = 0.008). CONCLUSIONS. Our data suggest that 13 edrenoceptor downregu!ation might be secondary to increased local synaptic catecholamine levels due to impaired uptake-1 mechanism in HCM patients.

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A new form of HSA (DMP-HSA, A) obtained by adding dimercaptopropionyl (DMP) groups to the original HSA and available as a kit for Tc99m labeling was pairly compared to labeled RBC (B) within 48h in 20 patients (10 M/10 F; mean age +/-SD: 60.8 +/11.5 yrs) showing a broad range of ejection fraction (El:) values. 15 min and 180 rain post-injection (pi) RNA and planar images of the thorax were acquired. Early (EF1) and late (EF2) EF values were calculated by 2 independent observers. Early and late planar images were used to determine the stability of both agents in terms of LV/surrmmding organs and late/early intra-organ activity ratios measured on left ventricle (LV), liver, spleen, right lung and a distant background. Image quality was excellent with both tracers, without significant image degradation at 180 min pi. Decay corrected LV/organ and late/early intra-organ ratios were similar for the two agents,ranging from 0.95 to 0.98. Interobserver variability was 1.08% (A) and 0.17% (B) for EF1, and 0.27% (A) and 0.62% (B) for EF2, timedependent intraobserver variability was -2.07% (p=0.023) for A and 0.28% for B, and inter-tracer variability was 0.36% for EFt and -1.99% for EF2 (p=0.04). Tc99m-DMP-HSA is thus a reliable new agent for RNA, offering a very interesting alternative to RBC. In our department, DMP-HSA has now completely replaced RBC and is routinely used for RNA and gastro-intestinal bleeding scans.

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M 46.1

46.3

MIBG IMAGING: ASSESSMENT OF DEFECTIVE MYOCARDIAL SYMPATHETIC INNERVATION IN FAMILIAL A M Y L O I D O S I S . N. Delahaye, D. Le Guludec, S. Dinanian, P. Merlet, H. Mzabi, D. Samuel, C. Adams, M. Slama, G. Mott6. Nuclear Medecine, Bichat Hospital, Paris, France. Patients with familial amyloid polyneuropathy (FAP) have impaired autonomic regulation of the heart that is thought to be due to conduction system infiltration rather than to dysinnervation. In order to evaluate the role of adrenergic dysinnervation, we studied by 1231 MIBG 8 patients with FAP (42+10 years) who were on the waiting list for liver transplantation. All had normal coronary angiogram, left ventricular systolic function (angiographic LVEF=72+7% cardiac index=3.2+0.5 I/mn/m 2) and rest thallium SPECT. At echographic examination only mild evidences of amyloid infiltration were found. Cardiac MIBG uptake was assessed as the heart to mediastinum activity ratio (H/M) measured on the chest anterior view planar image obtained 4 hours after intravenous injection of 8 mCi. A striking decrease in MIBG uptake was found in all FAP patients compared with age-matched control subjects (1.21+0.17 versus 1.96+_0.22, p<0.001). Washout rates (20mn/4h) were not different (28+5% versus 29+5%). Thus, patients with FAP showed impaired sympathetic myocardial innervation despite a preserved left ventricular systolic function.

Tc-99m FURIFOSMIN (Q-12) MYOCARDIAL PERFUSlON SPECT IN DETECTIONOF CORONARYARTERY DISEASE S Mahmood, J Bomanji, M Ayub, M Aleem, S A Sheikh, P J Ell Punjab Instituteof Cardiology, Lahore,Pakistan. Tc-99m Furifosmin is a recently developed compound for myocardial perfusion imaging. We prospectively evaluated diagnostic accuracy of this new compound in assessing CAD in 50 patients (42MISF, aged 36-70 years) with known coronary anatomy, using a two day stress - rest protocol. Myocardial perfusionsingle photon emissiontomography (SPECT) was performed using a single detector gamma camera, equipped with low energy high resolution collimator. Stress test was performed, using adenosineinfusion (140ug/kg/min.) combined with submaximalexercisestress of 25 watts incrementsfor six minutes. At 4th minute,400-450 MBq of Tc-99m Furifosmin was injected. 45 minutes later stress images were acquired, Resting data were collected next day. The reconstructed vertical long axis (VLA), horizontal long axis (HLA) and short axis (SA) slices were analyzed qualitatively,by three independentobservers, using nine segments of LV. The abnormal segments were reported either as fixed or reversible. The sensitivity and specificity for the detection of diseased coronary vessels (>50% stenosis) were 79% and 70% for the left anterior descendingterritoryrespectively,78% and 71% for the right coronary artery, and 73% and 69% for the left circumflex. Overall the sensitivitywas 76% and the specificity70%. We conclude that two day stress-rest Tc-99m Furifosmin myocardial perfusion SPECT results in similar diagnosticaccuracy as employingother agentsof the same group.

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Abstracts Tuesday morning, April 8, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

46.4

46.6

DETECTING ACUTE P U L M O N A R Y E M B O L I WITH TC-99m-P357. XL.Zhang, XJ.Liu, RF.Shi, ST.Li, YZ.Liu, BP.Chen, XS.Chen, and JS.Borer* Cardiovascular Institute Beijing, China; *New York Hospital, Cornell Medical Center

201-TL MYOCARDIAL PERFUSION TOMOGRAPHY BEFORE AND 3 MONTHS AFTER TRANSMYOCARDIAL LASER REVASCULARIZATION (TMLR)

The purpose of this study was to evaluate P-357 imaging in detecting acute Pulmonary Emboli(PE). 7 patients suspected o f acute PE were studied with planar and tomographic scinitigraphy using Siemens multi SPECT system. Images were obtained 20min, 1 and 2hr after injection Tc-99m-p357(55-740MBq). On tomographic images,Tc-99m-P357 accumulation in the lung was quantitated by a T/B ratio. In 3 acute PE cases, positive results with mutiple focal accumulation o f p357 in both lungs and 11 sites of thrombi were visualized within lhr, consistent with the Pulmonary angiography. The focal uptake o f Tc-99m-p357 was almost disappeared and no longer present post-thrombolysis and T/B ratio was decreased from 2.6 to 1.2. The negative results obtain in 1 patients with PE post thrombolysis and 3 patients with non-acute PE, In conclusion:Tc-99m-P357 may be useful in detecting PE.

R. Jochens, T. Parseh, T. Schumaeher, U. Engert, H. Amthauer, H. Bertram, W. Zendel, L. Tambeur, R. Hetzer, H. Eichst~idt Department of Imaging Cardiology and Radiology, Virchow-Clinic, Humboldt-University of Berlin, German Heart Center, Berlin, Germany Patients and methods: 42 of 120 patients who underwent a TMLR were investigated before and three months after TMLR, After intravenous application of 110 MBq 201-'1"1 images were obtained 10 rain. after dynamic exercise on a supine bicycle ergometer and three hours later, Images were performed with single- and three-head gamma camera. Visual and semiquantitative analysis in bull's eye-technique were undertaken. Results: Visual analysis of the stress/rest 201-TI studies before TMLR showed ischemia in 28•42 pat., no myocardial scars in 3•42 pat., intramural scars in 35/42 pat. and a transmural scars in 21/42 pat. The stress/rest 201-1"1 studies three months after TMLR showed in 25•42 pat. ischemia, no scars in 3/42 pat., intramural scars in 33/42 pat. and a transmural scar in 21/42 pat. In total 30•42 pat. showed an equal result in 201-TI scintigraphy before and after TMLR, in 6/42 pat. the result after TMLR was better than before and in 6/42 pat. there was a visual decrease of perfusion. Semiquantitative analysis showed equal results in 30•42 pat., a better result in 8•42 pat. and a decrease of perfusion in 4•42 pat. In 19/42 pat. the clinical situation improved three months after TMLR, no change could be observed in 19•42 pat. Conclusion: Although a clinical improvement three months after TMLR was observed in 50 % of all patients, there was no detectable change in 201-TI myocardial perfusion scintigraphy. Further investigations 6 and 12 months after TMLR must show if an improvement of myocardial perfusion can be visualized by 201-TI scintigraphy.

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46.5

46.7

VARIABILITY OF THE MEASUREMENT OF GLOBAL AND REGIONAL EJECTION FRACTION 1N DOBUTAMIDE VENTRICULOGRAPHY TEST. Y. Ricart, V. Vallejos, C. Romero, M. Ribas, A. Cequier, M. Roca, C. Pallards and J. Martin-Comin. Hospital de Bellvitge. Barcelona. Spain.

DOSIMETRiC E S T I M A T I O N IN M A N OF BIS [ ( N - E T H Y L , N-

The aim of the study was the validationof the cardiac ventriculographydobutamide testfor clinicalpractice. A gated ventriculography(bestanteriorleftoblique projection)under controlleddobatamide perfusion(basal,5 and 10 pg/kg,/min)was performed in 13 patients. The test was repeated within a 48 hours without modification in patient medication. No significant differences were seen between the first and the second study in the following parameters: heart rate, arterial pressure, global ejection fraction (GEF) and regional ejection fraction (REF) (postero-lateral (PL), infero-lmsterior (IP) and anteroseptal (AS)). The variability of GEF between both studies was 4.4 %, 5.9 % and 4.6 % for the basal, 5 and 10 gg studies respectively. For the same levels, the .variability of REF was respectively 9.1, 9.4 mad 10.4 % for the PL region, 8.6, 9.8 and 7.3 for the IP region and 5.2, 7.6 and 7.9 % for the AS region. Conclusions: The measurenmnt of GEF seems to be a valid parmneter when performing dobutalnide ventriculography. An increase of GEF> 5.9 % shoudl be considered as positive response. REF measurement shows larger variations, thus for the study of regional motility other parameters as cine mmlysis or parametries images may be of help.

ETHOXY) DITHIOCARBAMATE] NITRIDO TECHNETIUM (V) M. Giganti, L. Uceelli, C. Cittanti, P. Colamussi, G. Di Domenico, A. Duatti, C. Bolzati, R. Pasqualini, A. Piffanelli. Sperimental Clinical Medicine Dept., University of Ferrara, Italy. Bis[(N-ethyl, N-Ethoxy) dithiocarbamate] nitrido technetium (V) ([99"TcN-NOEt]) is a new, stable, neutral compound, that showed suitable characteristics for myocardial perfusion imaging. This study represents a preliminary evaluation of the dosimetrie estimation, calculated after injection in man of the agent, Three voluntary, fasted patients with CAD, were studied under stress and at rest. A 520 - 560 MBq dose of [99"Tc] NOET was administered i.v. Three sets of images (conjugate counting technique) were acquired at different times (30', 2 and 4 h). Whole body biodistribution was calculated. The radiation burden estimate was calculated following the MIRD tables, usin the mean biodistribution data obtained in the three Patients. ORGAN REST STRESS gGy/MBq pGy/M. Bq Myocardium 7,5 8,1 Kidneys 17,8 18,8 Liver 9,2 8j Lungs 4,7 5,8 Spleen 5,9,, 5,2 Thyroid 5,9 6,2 Ovaries I5,1 16,5 Testes 3,8 3~5 Bone Marrow 4,0 3,9 Whole Body 4,8 4,5 The above reported data shows that the radiation burden of TcNNOET is acceptable, and seems to be comparable to the other myocardial perfusion technetium agents.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Tuesday morning, April 8, 1997

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46.8

46.10

PROGRESSION01=MYOCARDIALMETABOLICABNORMALITIES MONITORED BY SPECT AND 10DINATED BETA-METHYL-

Detection of Coronary Artery Disease in Patients with

BRANCHED FATTY ACID ANALOGUE (I~31-BMIPP) IN PATIENTS WITH HYPERTROPHIC CARDIOMYOPATHY (HCM) Y. Shimotsu,Y. Ishida, N. Kume, Y. Hirose, K. Hayashida, M. Takamiya. National Cardiovascular Center, Osaka, Japan. To assess whether the monitoring of abnormalities in myocardial free fatty acid metabolism provides early detection of tissue damage in patients with HCM, we performed the follow-up study of the 15-rain initial and 4-hrdelayed 1231-BMIPP(13-methyl iodophenyl pentadecanoic acid) imaging and amTI imaging at rest and in the fasting state for 11 ptswith HCM (55 + 10yrs). ~231-BMIPPdefectswere frequentlyobserved in the hypertrophied regions and more extensive than 2mTI defects (total defect score, TDS : 9.7+5.9 in the initial ~3FBMIPP and 4.6+ 4.4 in a°~TIimages, p<0.02), Also, the findings of the initial and delayed 1231-BMIPP images were classified into 2 groups, 6 with fixed defects (Gp FD) and 5 with increased TDS from the initial to delayed imaging indicating regionally enhanced tracer washout (Gp HW). In the 2nd study performed 40 + 16 months after the 1st study, ~231-BMIPPdefects in the 15-rain initial images showed a marked progression (TDS: 9.7 + 5,9 to 10.8 4-6.0) in all patients, and those in Gp HW showed a more prominent progression (TDS: 9.5 +5.2 to 11.6 5: 5.0, p<0.01) than those in Gp FD (TDS: 10.3 + 6.9 to 10.2 4-7.0, ns). However, 2mTI defects, echocardiographically estimated left ventricular dimension and %fractional shortening showed no significant change between the 1st and 2nd studies. Thus, we detected the progression of metabolic abnormalities in the hypertrophied regions with ~231-BMIPPimaging in HCM. Also, this study suggest that regionally enhanced ~aI-BMIPP washout is an early sign of tissue metabolic involvement in HCM.

Congestive Heart Failure: Cornparison of BMIPP and T1 Hideki Fujita, Tatsumi Kuroda, Taigo Kintaka, Susumu Sakamoto, Masanobu Koide, Shyunji Suzuki, Hiroya Sakuramoto, Takefumi Matsuo. Hyogo Prefectural Awaji Hospital, Hyogo. Japan. The therapeutic sltrategy for congestive heart failure (CHF) depends on the presence of coronary arter 5 disease (CAD). The puroose of this study w ~ to determine whether I-'~I-BMI'PP (B) is superior to -°iT1 (T) in detection of CAD. Twenty-four patients with CHF (% fractional shortening on echoeardiogram <25%) underwent B and T scintigraphy at rest on separate days. Each scintigraphic SPF~T image was divided into 13 sectors to assess total defect score (sum of defect score, TDS), extent score (number of abnormal sectors, ES) and severity score (TDS/ES, SS) by using 4 grading defect score system (0=normal, l=mild, 2= moderate, 3= severe). Twelve of 24 patients demonstrated significant coronary artery stenosis (_>75%). Overall per patient sensitivity and specificity for CAD detection were 92% and 67% with B, whereas _50% and 58% with T. Comparison of TDS, ES and $S between patients with (1) and without CAD (NI~: TDS ..... ES S$ .... T B T B T B I

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7.9*

1.5

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NI 9.8 8.6 6.3 5.4 t ,4 1.4 *p<0.05 versus NI, #P<0.05 versus T. Conclusions: B scintigraphy has higher sensitivit), and specificity for the detectmn of CAD m patients wLth CHF than T scinti~3raphy. Moreover, the width and the severity of defect in scintigraphy lead to correct visual interpretation.

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46.9

46.11

MYOCARDIAL FIBROSIS AND UPTAKE OF RADIOIODINATED BRANCHED FATTY ACID: HISTOPATHOLOGICAL CORRELATION T.Kudoh, N.Hattori, M.Inubushi, J.Konishi, K.Nishimura, T.Ban, N.Tamaki. Kyoto University, Kyoto, Japan

THE DEPENDENCE OF MYOCARDIAL UPTAKE OF IODINE-123 LABELED BETA-METHYL IODOPHENYLPENTADECANOIC ACID (BMIPP) ON ENERGY SUBSTRATES. M. Nakamura, H. Shimizu, N. Isaka, T. Konishi, T. Nakano. Mie University, Tsu, Japan.

Recent reports suggest that 1-123 I~-methyl-iodophenylpentadecanoic acid (BMIPP) sometimes shows decreased uptake relative to thallium uptake in the CAD patients. To evaluate histological change according to decline of BMIPP uptake, myocardial biopsy was performed in 13 patient who undergo CABG. Previously to CABG, Rest TI and BMIPP SPECT were performed, and Bull's eye image was made. Nine regions of interest (ROI) were taken and %uptake of each ROI was calculated. From the specimen of biopsy, %Fibrosis was calculated.

%TI uptake %BMIPP uptake 100 ~ . ~ ' I ' ' ' I ' ' ' , ' ' ' , q 100 . . . . . . . . . 60

60

40

40

20

' 20 20 40 60 80 0 20 40 60 80 %Fibrosis %Fibrosis Decline of %uptake of BMIPP occurs in narrow range of very mild fibrosis (0-20%), whereas %uptake of TI well correlated with % fibrosis. This indicate that the decline of BMIPP uptake is very sensitive to myocardial ischemic damage, and has possibility to give different information to the perfusion imaging agents. 0

Myocardial uptake of free fatty acid (FFA) is dependent on their extracellular concentration. To clarify myocardial metabolism of BMIPP, we studied the effect of energy substrates on myocardial uptake of BMIPP. The whole body BMIPP imaging was acquired during fasting (overnight fasting state) and oral glucose loading (1 hour after drinking 75 g of glucose solution) in 6 normal volunteers (NVs) and 10 patients with ischemic heart disease (pts with IHD) to calculate the heart to whole body count ratio of BMIPP (% BMIPP uptake). The concentration of blood sugar (BS), insulin and FFA in blood samples obtained at the time of administration of BMIPP were measured. In NVs and pts with IHD, BS and insulin were higher during glucose loading than fasting and FFAwas higher during fasting than glucose loading. In NVs and pts with IHD, % BMIPP uptake were higher during fasting than glucose loading (2.5% v.s. 2.2%, p< 0.01, 1.8% v.s. 1.6%, p< 0.05, respectively). These results suggest that myocardial uptake of BMIPP is similar to that of serum fatty acid in relation to the concentration of energy substrates.

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Abstracts Tuesday morning, April,8, 1997

Journal of Nuclear Cardiology January/FebruaJ2¢ 1997, Part 2

46.12

46.14

RELATIONSHIP BETWEEN CARDIAC FUNCTION AND MYOCARDIAL PERFUSION: COMPARISON BETWEEN MYOCARDIAL INFARCTION AND ISCI-IEMIA, W I T H Te-TETROFOSMIN. k.Imai, T.Suzuki, K.Hashimoto, Y.Shimura, M.Mutoh, T.Shibata, H.Ogawa, J. Suwa, T. Horie, Saitama-Ohara Cardiovascular Center, Saitama, JAPAN

ASSESMENT OF REPERFUSION THERAPY IN ACUTE MYOCARDIAL INFARCTION BY T C - 9 9 M TETROFOSMIN AND I - 123 BMIPP SPECT IMAGING&

Cardiac function (F) and perfusion (P) are evaluated simultaneously by single injection of Te-Tetrofosmin (Tf). We studied whether the relationship between F and P are different between myocardial infarction (MI) and ischemia (IS). Left ventrieular ejection fraction (LVEF) was obtained for F. Extent score (ES) and severity score (SS) of defect on P image were analyzed. In IS, study was performed at rest in patient with anterior IS (n=21) and normal subjects (NOR1) (n=40). In MI, it was at exercise in patients sub ~cts with anterior MI (n=43) an =76).

Data shows as mean +/- SE. ES, SS and averaged severity (SS/ES) in IS were less than in MI, respectively. The relation between LVEF and SS was as follows: LVEF = -0,19 x SS + 60 in IS and LVEF = -0.13 x SS + 61 in MI. Decreased LVEF per SS in IS was greater than in MI. Thus, simultaneous evaluation with single Tf injection clarified that the perfusion abnormality and the relationship between F and P were different between M1 and IS.

Objective The effect of reperfusion therapy in acute myocardial infarction was evaluated by myocardial ~"¢rc-tetrofosmin (Tc) and mI-BMIPP (BM) SPECT imagings. Methods In 30 cases of first-time acute myocardial infarction with reperfusion accomplished by direct PTCA within 12 hours after onset, Tc images before PTCA, Tc and BM images within 1 weak, at 1 month and 3 manths after PTCA, and wall motion evainated by echocardiography and left ventriculography were studied. Results The area of defect in Tc images decreased after reperfusion therapy, which effect was more marked in the group with reperfusion within 6 hours after onset (21 cases). BM images showed a large defect within 1 week after reperfusion, which contracted at 1 month and later. Improvement of wall motion was detected at I month after reperfusion. Conclusion Tc imaging before and after mperfusion therapy in acute myocardial infarction and BM imaging initiated soon after reperfusion enabled us to evaluate myocardial salvage and risk areas, and to predict the improvement of wall motion in chronic phase.

46.13

46.15

OVERESTIMATION OF INFARCTION MEASURED BY Te-TETROFOSMIN IMAGE AT SUBACUTE PHASE. K. Imai, T.Suzuki, K. Hashimoto, Y.Shimura, M.Mutoh, T.Shibata. H.Ogawa, J.Suwa, T.Horie, Saitama-Ohara Cardiovascular Center, Saitama, JAPAN

PREDICTIVE VALUE OF 201 THALLIUM (20IT1) RESTREDISTRIBUTION MYOCARDIAL TOMOSCfNT[GRAPHY (SPECT) IN PRACTICE OF A CORONARY CARE UNIT. Peperstraete B., Martin Ph., Paternot J., Devriendt J.,Verhas M., Decoodt P. University Hospital Brugmann, Brussels, Belgium

IS MI NOR 2

T U E S D A Y

A.Kanazawa, W.Sasaki, K.Maki, K.Seki, H.Murayama, Y.Ogawa, Cardiovascular Department, Akita Kumiai General Hospital, Akita, Japan.

LVEF 53 +/- 2 48 +/- 2 62 4-/- 0.7

ES 0.27 +/- 0.05 0.49 +/- 0.03 0.01 +/- 0.01

SS 30 +/- 7 87 +/- 12 1 +/- 0.1

SS/ES 72 +/- 12 146 +/- 13 8 +/- 1

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Tc-Tetrofosmin (Tf) myocardial scintigraphy (MS) was used to evaluate the extent and severity of myocardial infarction (MI). We studied whether Tf-MS at subacute phase of M1 showed an actual defect due to MI. MS was performed 3 times, on day 4 +/- 2 (acute phase) after MI onset by Thallium (Ti), on day 22 +/- 7 (subaeute phase) and on day 137 +/- 40 (chronic phase) by Tf, in 26 patients with MI. For measurement of MI, the extent and severity of defect were analyzed on rest SPECT with normal database. Data shows as mean +/- SE. Defect TI (acute) Tf (subacute) Tf(chronic) 0.41 +/- 0.04 0.44 +/- 0.04 0.36 +/- 0.04 Extent Severity 63 +/- 13 80 +/- 13 57 +/- 11 There was not a significant difference in extent of defect among three groups. Severity of defect measured by Tf-MS at subaeute phase was greater than Tf-MS at chronic phase (p<0.01). Furthermore, it was greater than TI-MS at acute phase (p<0.05). Thus, Tf-MS at subacute phase, about 3 weeks after onset, overestimated severity of defect due to MI. In case of evaluation for the viability in infarcted myocardium by Tf-MS at subacute phase, we should consider the property of perfusion image.

There are few data concerning the predictive value of 20ITI restredistribution myocardial tomoscintigraphy (SPECT) in patients (pts) admitted for acute coronary syndrome. 17 pts admitted for incomplete (impending or subendocardial) infarction (Group 1, n=6) or complete (transmural) infarction (Group 2, n=ll) were studied. SPECT was obtained at rest (TI) after injection of 5 mCi of 201TI. Redistribution acqui,,ition (T2) was recorded 3 hours later, without tracer reinjection. According to the severity of the lesion, three or four segments were analysed on coronal slides. The activity of each segment was standardised to the peak activity of the study, to which a 100% value was assigned. Redistribution was defined as the presence of a segment with reduced captation (< 75 % of peak activib') at TI and increased captation at T2 of >10% of the initial activity. 10 pts were submitted to percutaneous transluminal coronary angioplasty (PTCA). For all pts, the late evolution (1 to 7 months) was compared to SPECT at the acute phase. Results (in brackets : number ofpts submitted to PTCA) Group 1 Group 2 N R+ RN R+ RFavourable evolution I (l) 4 (3) 0 1 (0) 2 (0) 6 (5) Unfavourable evolution 0 0 1(0) 0 1(1) 1(0) N : no captation defect ; R+ : redistribution ; R- : no redistribution. Conclus!on : In Group 1, redistribution was observed in most pts and was always associated with favourable evolution. In Group 2, absence of redistribution was observed in 7 out of I 1 pts but was not associated with unfavourable outcome, except in one non-PTCA case. PTCA appears thus useful in transmural infarction even in the absence of redistribution.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

46.16 SPECT MYOCAPJ)Lkl, PERFUSION LN THE DIFFERENTIAL DIAGNOSIS OF CHEST PAIN A'r 'I'HR EMERGENCY I:I,OOM. D. Bialoslozky.A. Pucnt e,JM C asanova,J.Cossio,L.Crespo,M. Lopez, E.Lupi,H.Oonz~.lez, J,AJtandrano.E.Alexanderson,V. Ancona,D.Victoria. Inslituto National de Cardiologia," tgnaci~ Chavcz." MEXICO. Objective Detemfine Specificity, Sensibilitv, Positive Predictive Value (PPV), Negative Predictive Value (NPV) or SPECT myocardial perfusion to predict coronary artery" disease at emergency room in patients with acute chest pain. Methods: Sixty patients. Each:12 lead I(KG. Chest X ray, SPECT myocardial perfiasion; 24 pts had ECHO and 30 cimm;u 3 angiogram. I. Emergency SPECT protocol: Thallium-201 al rest (diagnostic imaging in 20 mln); was followed , if needed: with mress SPECT (dypiridamol (50) or exercise (10); Sestamibi (57) Tetrofesmin (3); imaging : 80', (60' lo avoid cardiac contamination due to the retention at abdominal vicera): Total timed hr 40'. 11. Relative Urgency SPECT protocol: Sestamibi or Telrofosmin at rest: imaging 80 rain and if necessary followed with stress Sestamibi or Tetrolbsmin (anoth,:r 80 rain): Total time: 2 hr~ 40'. Results: Forty males, 20 females, age 54,3+14.5 years Chest pain: Angina: Typical:4l(Gg%), Atypical:19 (32%); First time: 28 (47%). Unstable:32 (53%); history previous infarct: l l (18%), EKG: Normal: 16 pts (27%). Non I)iagnoslic: 44 (73%): LBBI3:5 (11%), RBBB: 5 (11%), elevated J point as possible early injury: 7 (16%), ST depression : 6 (14%); small Q wave: 4 (9%), broad Q wave: 9 (20%), abnormal "Fwave (V2-6) 5 (11%), frequent extrasystotes, ventricular 2 (5%) and atrial 1 (2%). Sensibility: 75%, Specificity 29%, PPV 61%, NPV ,14%. ECHO: 24 pts (40%): Wall hypokiaecia: 14(58%), abnormal wall thickening:10 (42%), eiection fraction: > 50%: 21 (8g%). <50%: 3 (12%). Chest X ray: Cardiolhtmlcie index (%): < 5 0 : 4 1 pts (68%), 50-54:17 (28%), >55:2 (3%), venous hvperlension: 4 (6%). Coronal), Arterlogram: 30 pts (50%): with coronary obstruction ( 60%): 16 pts (53%), .Normal coronaries: 14 (47%). SPECT Myocurdial Perfilsion wUh Gated and Pohtr Map: Nomlal: 20 (33%); Abnormal: 40 (67%): Revetvible (ischemia): 21 (52%). Fixed ( necrosis): 16 (40%); Abnormal perfuslon at rest and normal wilh elIbrt: 3 (8%). In the group with Coronary angiogram (30) . 22 had abnormal SPECT (ischemie and;or necrosis) : 15 (68%) showed obstructive ctn-onary angiograna and seven (32%) normal coronaries. Eight pts had normal scmligraphy and one had obstructive coronal 3, angiogram. Sensibility 940/0, Spccilicity 55%, PPV 68°.-4, NPV 88% Conclusions: The SPECT Myocardial Perfusion Imaging has more sensibility, specific±t34 PPV and NPV than EKG to predict eooronary artery disease. Obstructive coronaL'y d{sease can be ruled out or confirmed at emergency room ill patients with chesl pain and non diagnostic EKG.Also microcircuIalory dcrangenlents was detected: chest pain, ischeraic SPECT changes and normal coronaries(Syndrome X).

Abstracts Tuesday morning, April 8, 1997

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46.18 THE DIAGNOSTIC VALUE OF Tc-99m TE TR OFOSMIN INFUSION AND NITRATE INFUSION STUDIES I N DETECTING OF VIABLE MYOCARDIUM:A COMPARATIVE STUDY WITH TI-201. A.O~demir, A.Boz, F.G~ngOr,].Baltao~lu, B.Karayalfm, M.Erluh¢. Akdeniz University, School of Medicine, Department of Nuclear Medicine, Antalya, Turkey. The aim o f this study was to determine o f the diagnostic value o f T c - 9 9 m tetrofosmin infusion (TFI) and Te-99m tetrofosmin bolus injection with nitrate infusion (TFNI) studies in the detection o f viable myocardium by comparing with T1-201Rest-Redistribution (Re-Rd) imaging. For this purpose, 8 men patients (age between 45-60 years) had previous myocardial infarction were included in this study. All patients underwent TI-201 ReRd, TFI, and TFNI studies, respectively.Totally 160 segments were evaluated. 36 segments showed hypoperfusion after T1-201 Re study. While 12 (33%) segments were improved in Rd imaging, only 6 (16%) and 10 (27%) segments were improved in TFI and TFNI studies, respectively. TI-201 Re-Rd study showed more improved segments than TFI and TFNI studies. These preliminary results suggest that TFNI study is a more promising technique compared to TFI study.

T U E S D A Y A M

46.17

46.19

Right Ventricle Infarction (RV-MI) SPECT diagnosis in the presence of Acute Left Inferior Myocardial Infarction (LI-M1). D Bialostozky,V Ancona,F Rovaletti,J Cossio,G Pozas,A Puente,E. Alexanderson,D.Victoria. Instituto Nacional de Cardiologia "Ignacio Chavez" Mexico. Objective: Describe SPECT inyocardial perfusion findings in patients wilh Acttle RV and Inferior Myocardial Infarction.Methods: Of 100 patients with consecutive isolated LIMI.Eighb (8ti%)showcd RV ischcmia and/or necrosis.Twenty six were studied in lhe first 5 days with SPECT protocol(DUAL in 16 and MIBI in 10:all with dipiridamol).RV was processed according to modified De Puey's technique .Cardiac catheterization with coronary angiogmnl was performed in all patients.Results: Twenty three were males and 3 females with mean 55.8 years (4262y),Clinical evidence of RV dysfunction was observed in 6 patients(23%),second and 3 rth degree transitory Atria-Ventricular Block in 5 (19%)Right Blunde Branch Block in 6 patients(23%),bradychardia in 2 (8%),RV3-RV4 ST elevation in 8(31%). X ray: Cardiomegaly in 5(19%),(with venous hypertension in 1 patient). Coronary Angiogram: coronary obstruction (>60%) of right coronary was observed in 12(65%).circunflex in 2(8%), left descending in 3(12%) and both right and circunl]ex in 4(15%). RV SPECT imaging showed dilatation of RV in 26 (100%),inferior RV necrosis in 8(31%), RV Jschcrnia in 18(69%), and five with necrosis and isehcmia.Conclasion:. All patients with Acute LI-MI showed RV dilaiatntion in SPECT myocardial perfusion althought only 23% of them had clinical evidence of RV dysfunction, Ischemic changes wcrc lbtmd lnorc frceuently than necrosis in RV SPECT.

CONTINUOUS THALLIUM-201 INFUSION FOR ASSESSING MYOCARDIAL VIABILITY IN HIBERNATING MYOCARDIUM H.Nishijima, Y.Imamura, and T.Fukuyama. Matsuyama Red Cross Hospital, Ehime, Japan We hypothesized that continuous infusion of ~°ITI augments its uptake into the low perfused but viable myocardium and accentuates the findings of "fill-in" into the hibernating myocardium with simultaneous usage of ~"Tc-MIBI. ~°~'TcMIBI bolus injection (740MBq) and ~ITI continuous infusion (111MBq) for 4 hours were applied simultaneously in 17 patients (60 #-2 yrs)with pe~stent perfusion defect by 2mTI stress SPECT prior to revascularization(Rev). Dual SPECT were acquired at 1 and 4 hours dudng "V'TI infusion. The patientswere divided into 2 groupsaccording to the finding of "filFin". Wall motion score (WMS)and LV ejection fraction (EF) were calculated from LVG and defect score, extent score and sevedty score were calculated from 2°1TI stress image before and after Rev. Asshown in the table, in the post-Rev LVG and #TI s'¢essSPECT, the patients with "fill-in"showed significant improvement of LV WMS as well as ~ITt uptake indexes. fill-in(+) (n=10) fill-in(-) (n=7) pre post pre post WMS 7.6±1.3 4.1±0.9"* 5.9£1.5 5.3±1.5 LVEF 59!:6 64+_4 57-±5 59-+-5 defect score 32~3 20±3** 29_L3 22!3 extent score 434__7 25±7** 35~8 28+_8 severity score 5 1 ! 1 3 28±12" 41±1 25_+.10 **p
A P R I L 8

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T U E S D A Y

Abstracts Tuesday morning, April 8, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

46.20

46.22

LOW DOSE ECHO DOBUTAMINE AND TI RESTRED. SPECT VS. MIBI AND TETROFOSMIN REST SPECT IN POST-AMI SEGMENTAL AKINESIA. A.Bruno,M.Castellani,A.Finzi,G.Marotta,R.Benti,G.Cali, U.LaMarchesina, S.Costantino,L.Preti,P.Gerundini. Depts. of Nuclear Medicine and Cardiology, IRCCSOspedale Maggiore - Milan, Italy

THE INFLUENCE OF ST RE-ELEVATION AT THE TIME OF RECANALIZATION ON MYOCARDIAL SALVAGE EFFECT IN ACUTE MYOCARDIAL INFARCTION. I.Murata, S.Watanabe, Y.Hashimoto, K.Watanabe, K.Hayakawa, S.Tanihata, H.Matsuo, T.Matsubara, Y.Matsuno, H.Qda, Y.Kotoo, H.Ohashi, Division of Cardiology, Gifu Prefectural Hospital, Gifu, Japan

Investigational imaging procedures to assess pre revascularization viability as rest SPECT with MIBI and Tetrofosmin (TF) were compared with high specificity low dose Dobutarnine (DO) echocardiography and sensitive SPECT Thallium (T1) rest-redistribution. We studied 31 pts.(16 segments each) at 1-6 months from AMI. In 64/223 aldnesic segments on basal echo with contractility recover during DO infusion, TF had higher perfusion score in 10 (mean %uptake: 61 vs. 52%) vs. 3 with MIBI (70 vs. 62%) and better %uptake than MIBI in areas with lower perfusion score. In segments with DO response and TI redistribution Tc-99m agents had similar mean % uptake (62% MIBI and 65% TF) but better with TF in 66% of them. We conclude that TF rest SPECT has slightly better specificity vs. MIBI in viable akinesic areas. Comparison with TI redistribution shows similar uptake and thus sensitivity for viability assessment.

To evaluatethe meaning of ST re-elevation in terms of myocardial salvage effect by repurfusion therapy, the myocardial area at risk (AAR) and infarct size(IS) were assessed using 9~'Tc sestamibi (MIBI) in a consecutive sedes of 30 AMI patients with TIMI0 or 1 flow who subsequently underwent acute reperfusion therapy (M:F=21:9, age:64.5 +_11.3, IRA:LAD 16, RCA 8, LCX 6). SPECT imaging with MIBI was obtained to quantitate AAR and IS. The abnormality of perfusion was expressed as a percentage of the entire myocardium using polar maps for extent(ES) and severity(SS). Improvement was calculated by the following equations : %LV= ES(AAR)-ES(IS) which indicates the percent of LV salvaged, %RA= [SS(AAR)-SS (IS) ]/SS(AAR) which implies the percentage of risk area salvaged. Results. Patients were divided into 3 subsets ; the patients with(n=6),and without(n=16) ST re-elevation just at the time of recanalization and with unsuccessful repurfusion(n=8). Successful repurfusion resulted in greater myocardial salvage than unsuccessful therapy regardless of the presence or absense of ST re-elevation, furthenmore,the patients without ST re-elevation showed larger amount of myocaldium salvaged . . . . ~o~fo~o, ~,~°,~°~+) ,°~,,~°,~o.~, s,~ re-ele~aLiellf+JsT re~leva%~em(-] than the patients with S T ~ ,+~= ~..±, ~,, re-elevation as shown in " ' ~,~, ~,~ 6,,:22 the table. Conculusion.ST re-elevation at the time of recanalization may be an important phenomenon representing the reperfusion injury.

A M A P R I L 8

46.21

46.23

OlPY~IDAMOLE-DOBUTAMINE SCINTIGRAPHY IS NOT SUPERIOR TO 9OBUTAMINE SCINTIGRAPHYIN ~DENTIFYINGPATIENTS W~TH MULTIVESSEL CORONARYARTERYDISEASE POSTivtYOCARDIALINFARCTION.

MYOCARDIAL METABOLIC ABNORMALITIES IN PATIENTS WITH RIGHT VENTRICULAR PRESSURE OVERLOAD: ESTIMATION BY 1231-~-METHYL IODOPHENYL PENTADECANOIC ACID (BMIPP). N. Yoshimura, Y. Ishida, K. Nagaya, Y. Hirose, Y. Shimotsu, N. Kume, K. Hayashida, M. Takamiya. National Cardiovascular Center, Osaka, Japan

,;. ?rassopouios. •. Lekakis. A. Vezyrgianni, J. Germanidis. Ch. ?aiaistides.P. Kostamis."Alexandra"Univ. Hospital Athens.Greece. iaipyridamole-Dobutamine(DiDo) Scintigraphy(Sc) may be superiorto Oobutamine(Do) Sc by combin;ri.~the vasodilationof Di and increase of the .3oubleproduct of Do. We comparedthe results of DiDo Sc and L~o Sc in patients (pts) with muitivessel disease post myocardial :nfarction. DiDo 99mTc-tetrofosmin 3PEOT was pedormed in 15 pts post infarction (GroudA). Di was infused for 4 rain (0.56 mg/kg) and subsequently Do (10-40 ptg/kg/min. 3 rain stages) was infused. Do 39mT:-tetrofosntin SPECT was pedormed in 20 pts post infarction Group B) CoronaLvarteriographyrevealed28 diseasedvessels (V) in ,,i~out: A (1,86 'v/p~) and 43 diseased V in group B (2.15 V/pt. ns), :~F[.CT detected 22/28 V in group A (82%) and 34/43 V in group B 79~Y~ns). LAD wss diseasedin 10 pts of group A and detectedin 9/10 (90~), LAD was diseased in 18 pts ol group B and detectedin 16/18 i'38%, ns) LCx ~as diseased in 9 pts of group A and detected in 6/9 (66%): LCx was diseased in 14 pts of group B and detected in 8/14 57%. qs). RCA was diseasedin 9 pts ot group A and detectedin 8/9 (88%): RCA was diseasedin !I ~ts of group B and detectedin 10/tl (91%. ns), There were 2 false positive results in group A (1 RCA, 1 LAL-:) "rod 2 false poskive ~ssults in group B (2 RCA, ns). First pass ~jection fraction decreaseaat stress in 33% of pts in group A and 40% ct.': in groupB m conclusion, con=b~n~ng0i with Do is not superior to simple Do scmtigraphy. First pass ejection fraction during both tests is not helptut ;n identifyingmultivesseldiseasepost myocardialinfarction.

To assess the effect of persistent ventricular pressure overload on myocardial metabolism, we studied myocardial peffusion and free fatty acid utilization by ~Tc-sestamibi (MIBI) and laI-BMIPP (BMIPP) SPECT imaging, respectively, in 22 patients with right ventricular pressure overload : 10 with pulmonary thromboembolism, 7 with primary pulmonary hypertension, 4 with congenital atrial septal defect and 1 with neoplasma in the pulmonary artery. In the midventricular short-axis tomogram, we determined tracer distribution ratio of right ventricular free wall to left ventricular free wall (RV/LV). The patients were divided into 3 groups based on mean pulmonary artery pressure (mPA), 9 with 20 to 40 mmHg (Gp A), 8 with 40 to 60 mmHg (Gp B) and 5 with >60 mmHg (Gp C). RV/LV in MIBI and in BMIPP were correlated with mPA (r=0.72 and r=0.58, respectively). However, the slope of the regression line was lower in BMIPP than in MIBI, and the difference of RV/LV between MIBI and BMIPP was significantly higher in Gp C than in Gp A (p<0.01) and Gp B (p<0.01), respectively. These results suggest that the combined monitoring of right ventricular MIBI and 8MIPP myocardial uptake is useful for assessing the severity of right ventricular pressure overload.

Journal of Nuclear Cardiology Volume 4, Number t, Part 2

Abstracts Tuesday morning, April 8, 1997

46.24

46.26

RELATION OF MYOCYTE NECROSIS TO VIRAL PERSISTENCE IN DILATED CARDIOMYOPATHY

USEFULNESS OF ANTIMYOSINSCAN IN MYOCARDITIS A. Millaire, P. de Groote, C. Foucher-Hossein, P. Guimier, O.

F.Bengel, H.Feistet, W.Moshage, K.Bachmann and F.Wolf Dept. of Nuclear Medicine, Univ. of Erlangen, Germmo~ Viral persistence in the myocardium late after infection is discussed to be a factor involved in the pathogenesis of idiopathic dilated cardiomyopathy (DCM). For investigation of its relation to the extend of ceil necrosis, we prospectively studied 10 pts with DCM. Myocyte membrane damage was quantified by planar in-111-antimyosin scans and a heart/lung ratio (HLR) 48 h after injection. Myocardial biopsy and polymerase chain reaction (PCR) were performed for specific detection of persisting viral RNA in the myocardium. Antimyosin scintigraphy revealed a HLR of 1.78+0.18 for 8 pts with DCM and negative PCR, whereas HLR was significantly lower (1.46+0.18; p<0,032) in 2 pts with DCM and positive PCR consistent with myocardial persistence of coxsackie B virus. The presented data suggest that myocardial persistence of viral RNA is not associated with increased myocyte damage. If viral persistence is a relevant factor for pathogenesis of DCM, other mechanisms such as contractile function or utilisation of energy may be affected.

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Nugue, X. Marchandise, G. Duclou×. University of Lille, France. Antimyosin scan (AMS) is a noninvasive tool used for diagnosing myocarditis (M). This test may remain negative despite a histol3, or a clinical presentation highly suggestive of M. One explanation could be that, in some patients (pts), the size of the myocardial inflammatory involvement is too small to be detected. To test this hypothesis, we investigated 3 lypes of pts : 1) M with high serum levels of creatine kinase (CK) enzymes (> 300 UI/I) ; 2) M with low levels of CK (< 300) ; 3) pure pericarditis with normal levels of CK. The diagnosis was based on a body of argtunents including clinical (chest pain, pericardial rub), ECG (acute changes with a further complete recovery) and biological signs (inflammation, viral titers). If AMS was positive, a late control at 6 months was performed. Pts with a previously known heart disease were excluded. Eight pts were included (5 males, 3 females, age 22 to 55 years old, mean 38). CK were highly increased in 4 pts (700 to 1600 uttits), moderately increased in 2 pts and normal in the 2 last pts. In all pts, 2-D echo showed normal left ventrioular function and dimensions. Early AMS was positive in the 4 pts with a high level of CK (myocardial/pulmonary uptake rates ranged from 1.53 to 2.00 ; uptake was diffuse in 1 pt and localized in 3 pts) and was negative in the 4 other pts with moderate increase of CK or normal CK. AMS normalized at late control. In conclusion, our results support the hypothesis that antimyosin scan may remain negative in case of small focal myocarditis with a low serum release of CK enzymes.

iJ E S E ¥ iV

46.25

46.27

IMPAIRED UPTAKE-1 FUNCTION IN CARDIOMYOPATHY S. Wakasugi, A. Noguchi, T. Hashizume, K. Ibuka,Y. Hasegawa. The Center for Cancer and Cardiovascular Diseases, Osaka, Japan

SIGNIFICANCE OF ABNORMAL SCAN IMAGES IN HYPERTROPHIC CARDIOMYOPATHY BY EXERCISE THALLIUM-201 SPECT N.Tanaka, T.Kamada, R.Baral, H.Nohara, H.Iino, M.Ishimaru, K.Takeda, I.Harada, K.Takazawa, Y.Kobayashi, C.Ibukiyama. Tokyo Medical College, Tokyo, Japan

We have previously shown that washout rate (WR) of I-123-MIBG from the heart in normal cases with intact uptake-1 function is increased more than 5.0%/hr. by pretreatment of uptake-1 inhibitor, imipramine (IMP) compared to control. Enhancement of WR of MIBG with IMP may be less in the heart with impaired uptake-1 function. 1-123-MIBG studies (planar and SPECT imagings) with pretreatment of IMP were performed within 2 months after control studies in 21 patients (pts) with dilated cardiomyopathy (DCM) and 43 pts with hypertrophic cardiomyo-pathy (HCM). All pts were divided into normal response (NR) group (n=39, increase of WR with IMP >5.0%/hr.) and low response (LR) group (n=25, increase of WR < 5.0%/hr.). NR was observed in 30 HCM and 9 DCM pts (increase of WR=9.4+3.5%/hr.) and LR was observed in 13 HCM and 12 DCM pts (increase of WR=1.5--+2.5%/hr.). WR in control images was higher in LR group compared to NR group (16.6--+7.7%/hr. vs 11.3--+ 4.6 %/hr., p<0.001). In LR ~oup, increase of WR was very few (0.30-t-4.1%/hr.) in defect segments (seg.) and also in non-defect seg. (2.9+2.4%/hr.). 28 of 39 pts (22 HCM and 6 DCM) in NR group showed homogeneous enhancement of WR (10.9-----4.2%/hr. in defect seg. vs 10.1+3.9%bar. in non-defect seg., NS). 11 pts in NR group (8 HCM and 3 DCM) showed heterogeneous response (HR) (4.7+2.2%/hr. in defect seg. vs 9.9--+3.1%/hr. in non-defect seg., p<0.0001). Conclusions: 1) LR or HR to IMP suggests diffuse or local impairment of uptake-1 function. 2) Impaired uptake-I function is observed not only in DCM but also in HCM.

The role of scintigraphy in evaluating cardiac function of hypertrophic cardiomyopathy (HCM) is still obscure. The purpose of this study was to clarify the relationship between cardiac function and the abnormal scan image. A total of 22 Maron type-II HCM patients underwent thallium SPECT and cardiac catheterization. These HCM patients were divided into two groups of normal scan (n=14) and abnormal scan (n=8). Systolic function (ejection fraction: EF) and diastolic function (Tau) data as well as degree of squeezing severity of septal perforators using a 4-point scale (Sq. Score) were derived from catheterization. Age (yrs) IVS 0ran) EF (%) Tan (msec) Sq. Score

Nonml 58.1 • 16.6 16.4 :~ 3.2 73.1 4- 5.4 63.1 ± 9.6 0.6 4- 0.8

Abnormal 49.9 + 11.1 19.5 4- 3.3 60.7 + 15.6 90,0 4- 14.6 1.9 ± 0.9

P NS <0.05 NS <0,05 <0.05

Our data suggests that abnormal scan of interventricular septum Maron type-ll on exercise thallium SPECT is a sign of diastolic dysfunction representing early stage ischemia.

F I L

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T U E S D A Y

Abstracts Tuesday morning, April 8, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

46.28

46.30

DISCREPANCY BETWEEN 2mTLCL AND I~I-BMIPP MYOCARDIAL SCINTIGRAPHY IS RELATED TO MYOCARDIAL FIBROSIS IN I D I O P A T H I C CARDIOMYOPATHY. Y. Hiruta, H. Yamao, T. Satoh, M. Yui, T. Ichihara. Iwaki Kyoritsu General Hospital, Iwaki, Japan.

1-123 BlVlIPP MYOCARDIAL SCINTIGRAPHYSHOW TIlE DIFFERENCES OF FATTY ACID METABOLIC DISTURBANCESBETWEEN THE PATIENTS WITH DILATED CARDIOMYOPATHYAND AORTIC REGURGITATION. Y. Suzuki, T. Toyama, N. Isobe, T Iwasaki, T. Suzuki, R. Nagai, T. Inoue and K. Endo. The Society of Gunma Myocardial Metabolism, Maebashi, Japan.

Histopathological studies ware made to elucidate the cause of discrepancy between 2O~TICIand ~231-BMIPP (/3 -methyliodophenyl pentadecanoic acid) myocardial scintigraphy in idiopathic cardiomyopathy. 46consecutive patients (21hypertrophic cardiomyopathy (HCM) and 25dilated cardiomyopathy (DCM)) were investigated. Dual SPECT at rest and endomyocardial biopsy were performed. Patients were classfied into two groups according to the presence of discrepancy. We compared both groups in following respects: myocardial hypertrophy, disarray, and fibrosis. The discrepancy was revealed in 10cases Of HCM (48%) and 2 of DCM (8%), at the accumulation site of 2mTICI uptake being defect area in ~231-BMIPP. Histologically, the discrepancy correlated to myocardial fibrosis only. That was seen in the cases with less than moderate fibrosis, and disappeared in the cases with extensive fibrosis. In conclusion, myocardial fibrosis is associated with the discrepancy between 2OlTICI and 1231-BMIPP myocardial scintigraphy in idiopathic cardiomyopathy.

To characterize the differences of fatty add metabolism between the patients with dilated cardiomyopathy (DCM) and aortic regurgitation (.AFt), we performed 1-123 betamethyliodophenyt pentadecanoic acid (BNIPP) myocardial scintigraphy on 24 patients with DCM, 8 with AR and 8 normal controls (NC). BMIPP SPECT images were collected 15 minutes (E) and 4 hr (D) after tracer injection. From SPECT image, regional tracer uptake was scored semiquantitativelyusing 4-point scoringsystem (0= normal ~ 3= defect) in 20 segments. Total uptake score (TITS)was the sum of regional tracer uptake scores. (# p<0.05 vs AR) DCM(n=24) A R ( n = 8 ) NC(n=8) BMIPP-TUS(Early) 17_+13 8+8 0 BMIPP-TUS(Delayed) 16_+11# 7_+4 0 .In the patients with DCM and AR, the area of fatty acid metabolic disturbance were apical and inferior walls. Further more, in the patients with DCM, the metabolic disturbed area was extended to anteroseptal wall. These results suggest that BMIPP delayed images can be usefifl to detect more severely and largely fatty acid metabolic disturbances in the patients with DCM than in the patients with AP~

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46.40

A M A P R I L 8

ARE THE SCINTIGRAPHIC PATTERNS DIFFERENT IN ISCHEMIC AND NON-ISCHEMIC CARDIOMYOPATHIES ? F Pfigent, S Bellam, R Steingart. WinthropUniversity Hospital, Mineola & SUNY at Stonybrook, NY It is not known whether the SPECT scintigraphie patterns are different in isehemic (I) and non-ischemie (NI) cardiomyopathies (C). Accordingly, the stress Tl-201 SPECT images of 37 patients (pts)with known C (24 IC, 13 NIC) were blindly analyzed using the 20 segment scoring system. Extent score (ES), severity score (SS, % maximal counts)~ LV dilatation at stress or aneurysm (LVD) and lung / heart ratio (LHR) were compared. Results: Comparing I & NI C, respectively, the % ejection fraction was 31 + 8 vs 37 + 7 (p <.04); ES was 8.6+2.9 vs 3.7 + 3.2 (p<.000l); SS was 34 + 1 6 vs 55 + 9 (p <.001); LHR was .64 + .20 vs .42 + .9 (p <.001). 8/24 pts with IC had LVD vs none with NIC (p<.04). By multivariate analysis, 0nly the ES was different between the 2 groups (p<.00l). The best discriminative criterion, by ROC analysis, was combining ES > 6 and SS < 45 which resulted in 79% and 85% correct classifications into I and NI C, respectively. LVD or LHR were 100 % specific for IC but poorly sensitive, 33 and 58%, respectively. Thus, SPECT seintigraphic patterns are different in ischemie and non-ischemic eardiomyopathies. Discriminative criteria need to be validated in a prospective population.

EVALUATION OF FDG PET, DOBUTAMINE ECHO AND CORONARY ANGIOGRAPHY IN INFARCT PATIENTS WITH EXERCISE-INDUCED T-WAVE NORMALIZATION (ETN). P.Zanco, GMobilia, F. Chierichetti, S.Cargnel, D. Rubello, A. FiN, R.Buchberger and G.Ferlin. Nuclear Medicine - PET Center, Castelfranco V. and Cardiology, Montebelluna, Italy.

To evaluate the meaning of ETN, 25 pts with Q-wave AMI and rest predischarge negative T-wave in > 2 infarct-related ECG leads (IRL), were studied within 1 mo. of AMI by ergometric test, dobutamine-echocardiography (DE), F18FDG (glucose-load) positron emission tomography (PET) and coronary angiography (CA). PET viability was defined as an FDG uptake >_ 50% of the maximum; DE ischemia was considered present when a worsening of regional wall motion occurred during dobutamine infusion. ETN occurred in 15 pts (gr. I) and did not occur in 10 pts ((jr. 2). The number of pts, in whom PET-viability, DE-ischemia and a TIMl-flow grade > 2 in infarct-related artery, were found, are reported in table: I viability ischemia TIMI > 2

g"'2 gr.

I

;I

75 4° *= p<0.05 (vs. gr. 1) In conclusion our experience suggests that ETN in IRL, after AMI, could indicate the presence of residual viability in infarct area, as confirmed by FDG-PET. No correlation was found between ETN and stress-ischemia at DE, or coronary stenoses at CA, in infarct area.

Journal of Nuclear Cardiology Volume 4, Number t, Part 2

Abstracts Tuesday morning, April 8, 1997

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46.43

46.41 ARE Te-99mSESTAMIBI(Mihi)AND TETROFOSMIN(Tf) EQUIVALENT FOR ASSESSMENT OF MYOCARDIALSYSTOLICTHICKENING(ST) WITH GATED SPECT (GSPECT) ? A.S. Hamb?e, A. Vervaet, R.Vandermeiren, J. Vandevivere, A. Dobbeleir. Middelheim Hospital, Antwerp, Belgium.

Head-to-head prognostic Sestamibi tomography eehocardiography testing myocardial infarction.

comparison between exercise (MIBI) and dipyridamole( D E T ) in s t a b l e p a t i e n t s a f t e r

N.R. Petix, G. Marcucci*, M. Silvestri*, A. Arena *, V. Mazzoni, A. Bini, A. Mcnnuti *. Department of Cardiology, Empoli ( Fi ) and * Department of Nuclear Medicine, Prato, Italy,

GSPECT, based on changes in count density (CD) during the cardiac cycle, can reliably assess residual ST (and thus viable tissue) after myocardial infarction (MI). Since Tf shows a slightly lower cardiac uptake than Mibi, we wondered if both were even accurate to identify ST, especially in areas of decreased perfusion. 40 patients (17 M/23 F; mean age (SD): 60.9 (13.9) yrs; 15 with prior MI) referred for a 2-day stress/rest test were prospectively included. Tf or Mibi were randomly injected in 20 pats each (same tracer for the 2 tests, mean (SD) injected Tc99m: 943(46) MBq, whatever the agent used). 8-bins ECG-GSPECT started 30-45 (Tf) to 60-90 (Mibi) rain postinjection. Gated and summed data were qualitatively and quantitatively analyzed by 3 independent observers. ST, representing the % regional increase in CD between diastole (D) and systole (S) measured on D and S bull's eyes, was compared to other methods for wall motion (WM) analysis. Relative regional uptake and image quality on the summed data were not significantly different between Tf and Mibi (p = 0.108) despite significantly less subdiaphragmatic activity with Tf, peeularly at rest (p=0.018). Both showed similar % ST in normal walls (30-60% vs 35-60%). Normal/decreased % ST correlated highly with WM analysis on echocardiography or contrast angiography (sens/spec: 1.0/0.83 for Tf; 0.87/1.0 for Mibi). Tf and Mibi are thus equally acurrate to assess ST, even in severely hypoperfused regions.

In order to compare the prognostic value of DET and exercise MIBI scintigraphy in clinically stable pts after a first uncomplicated myocardial infarction, 107 pts (85 m, mean age _56, range 32 to 72 ) underwent DET and MIBI scintigraphy after 4 weeks (50 ± 10 days) from an acute coronary event. On follow-up (24 +_8 months), a hard cardiac event (HCE) occurred in 10 pts (2 deaths and 8 reinfarction) and 35 pts developed angina. The cumulative probability of HCE did not differ in relation to DET and MIBI results. By multivariate analysis of clinical, stress and image variables, the only best predictor of a future HCE was the peak stress wall motion score index (WMSI) (relative risk [RR], 6.3; confidence index [CI] 95%, 1.5-l.8; p -< 0.01). When angina was considered separately, a significant better con'elation was found between the occurence of angina and positive DET results, than exercise-induced reversible MIBI defect. On Cox analysis, the independent predictors of subsequent angina were the peak stress WMSI (RR, 2.5; CI 95%, 1.00-2.37; p <_ 0.03) and the number of reversible MIBI defects (RR, 1.1 ; CI 95%, 0-9; p < 0.04). Cumulative angina-free survival rate obtained by the combination of DET and MIBI results were statistically different and showed a txx)r clinical outcome in pts with both tests or only DET positive. Thus in late postinlhrction risk stratification DET and MIBI images have a limited usefulness in predicting HCE, whereas the pts at risk of angina can consistently be better identified by DET results.

46.42

46.44

PROGNOSTIC VALUE OF THALLIUM-20I REINJECTION AFTER EXCISE-REDISTRIBUTION IMAGING IN PATIENTS WITH CHRONIC CORONARY ARTERY DISEASE.

THE EFFECT OF HORMONE REPLACEMENT THERAPY ON MYOCARDIAL PEP,FUSION AND OXIDATIVE PROCESSES IN POSTMENOPAUSALWOMEN M.Ka~aierczak, H.Wysocki, M.Dydowicz, A.SzymankiewiczWarenik, A.Minczykowski, T.Siminiak, J.Sowinski, University School of Medical Sciences, Poznafi, Poland

S.Kobayashi, N.Takahashi, Y.Mitani, and M.IshiL 2rid Dept. of Int. Med. Yokomaha city university, Yokohama, Japan. Recently~ ThaUium-201(TI-201) reinjection imaging has improved the accuracy in identifying viable myocardinm over that achieved by redistribution imaging alone, however, its prognostic value is still unknown.The aim of this study was to assess the iltcremental prognostic value of TI-201 reinjectioa in medically treated patients with chronic stable coronary disease undergoing excise-redistribution T1201 protocol Resting TI-201 reinjecUon (371~fBq. iv.) after conventional exciseredislribu~on Tb20l (lllMBq. iv.) tamographic imaging was performed in 61 consecutive patients with a clinical history of prior myocardial infarction (8>weeks) or Q wave on the ECG. Follow-up data (Mean 21.4 month) were available for 49 patients. Of thee patients, 12 underwent early revascuinrizanon within 3 mouths after cardiac imaging and were excluded from this study. During the follow.up phase, there were coronary event (cardiac death, nonfatal myocardial infarction and coronary revascalariratinn procedures more than 3 months after TI-201 imaging). The number of reversible defects at exciseredistribution imaging could not detect coronary event, on the other hands, the sum of reversible and moderate irreversible TI-201 defect after retnjectimi and the number of reversible defects at exclse-redistribution imagins] improved the chl-sqnare. Meceover~ the irreversible TI-201 defect after reinjection did not show subsequent coronary event. These results demonstrate that inpatients with previous myocardial infarcthm, T1-201 reinjection imaging provides incremental prognostic information over those obtained from conventional exciseredistribution TI-201 tomography. coronary event (+) reversible redistribution Irreversible redistribution

4

5

coronary event (-)

coronary event (+)

coronary event (-)

14

reversible reinjection

9

24

14

irreversible relnjecfion

0

4

A rapid progress of atherogenesis has been observed in postmenopausal (PM) women. Reactive ox3'gen species are known to contribute to the development of atherosclerosis. We have previously reported that myocardial ischaemia correlates with plasma level of hydrogen peroxide (H202). Aim: Evaluation the effect oestrogen and progestogen hormone replacement therapy (HRT) on myocardial perfusion and plasma levels of H202 in PM-women. Material: 21 PM-women, aged 46-59 years, presenting with angina. M e t h o d : Tc99m-M1BI SPECT (25 mCi) was performed at rest and after dipyridamole (Cyrantyl; Berlin-Chemie) test. The severity of ischemia was defined by 5 point scale in 9 segments of the left ventricle. H202 plasma level was determined by colorimetric assay. Blood for 1,1202 determination was obtained before test and 5 minutes after dipyridamole injection. The protocol was repeated after 6-15 months tIP,T: 50gg 17-13 oestmdiol (Systen; Cilag) and 10mg medroxyprogesterone acetate (Provera; Upjohn). Results: before HRT after HRT p< radiotracer accumulation at rest (pt.) 14.1±2.2 14.64-2.1 n.s. after dipyridamole 13.8±1.1 14.5±0.7 0.05 plasma 1-I202 at rest (/.tND 5.6J:1.7 3.4~0.8 0.05 after dipyridamole 4.9±1. 3.2±0.9 0.05 Conclusions: 1. HRT exerts a beneficial effect on myocardial perfusion in PM-women, as evaluated by Tc99m-MIBI SPECT 2. HRT in PM-women significantly decreases plasma levels of H202.

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Abstracts Tuesday morning, April 8, 1997

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NON INVASIVE ASSESMENT OF CARDIAC RISK IN TYPE I DIABETIC PATIENTS BEING EVALUATED FOR COMBINED PANCREAS.KIDNEY TRANSPLANTATION (PKT) USING DYPIRIDAMOLE-MIBI PERFUSION TOMOGRAPHIC SCINTIGRAPHY. D. Fuster, A. Muxi, J. Pascual *, J. Magrifi6 **. M J, Ricart *, FJ. Setoain, S. VidaI-Sicart, E. Esmatjes ***, A. Garcia. Nuclear Medicine, Renal Transplant Unit * Cardiology ** and Endocrinology *** Departments. Clinic Hospital. Barcelona Spain.

USEFULNESS OF QUANTITATIVE REST BMIPP SPECT IMAGING FOR DETECTION OF MYOCARDIAL ISCHEMIA BY USING POLAR MAPS AND STANDARD NORMAL LIMITS N.Taka hashi,YMitani,S. Sumita,K. Ashino,H.Ochiai,N.Miyazaki, M.Ishii.Yokohama City University,Kanagawa,Japan

Dypiridamole-MIBI Scintigraphy may be useful in identifying diabetic patients at low risk for Pancreas-Kidney Transplantation and may obviate in a large group the need far routine coronary angiography.

Iodine-123 (I-123) free fatty acid analogues allow for metabolic studies with SPECT. Because of difference of the ener~- and myocardial distribution between 1-123 and TI-20t, we obtained normal polar map files of both tracers. BMIPP (lllMBq) and TI (111MBq) rest myocardial SPECT imaging were acquired 15 rain. after injection in 10 normal patients (5 male and 5 female) and 20 normal patients ( 10 male and 10 female). Percent uptake and standard deviation (SD) were calculated in 16 segments of each normal files. For assessment of ischemia, rest BMIPP and exercise T1 (ExT1) were performed in 50 patients of ischemic heart disease with siglfificant coronary stenosis (>75%) (age:604-9, number of significant stenosis region were 89). ExTI were performed 10 4-6 days after BMIPP study. We assessed BMIPP by visual evaluation (VE) and quantitative objective evaluation (DE) by using normal file by two doctors. The segments showed reduced %uptake below mean -2SD were significant. Diagnostic results were as followed. BMIPP(VE) BMIPP(OE) ExT1 sensitivity 60% 79% 81% specificity 93% 89% 92% accuracy 79% 85% 87% Especially in 59 ischemic regions wifllout prior myocardial infarction (nonMI), sensitivity and accuracy of VE were improved by DE (VE vs DE: 39% vs 69%, 67% vs 79%). Quantitative rest BMIPP SPECT were useful study to evaluate of severe isehemia with regional wall motion abnormalities.

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46.48

Actual data indicates that is necessary to prevent cardiovascular death in PKT. We examined the value of Dypiridamole-MIBI perfusion scintigraphy in non invasive assessment of cardiac risk in 55 type I diabetic patients (pts) being evaluated for combined PKT.

T U E S D A Y

Journal of Nuclear Cardiology January/February 1997, Part 2

Tomographic images were normal or without clinical significance in 46 pts (83.6%). In the remaining 9 pts (16.4%} coronary arteriography was performed. The results were: 2 normal, 4 non significant lesions and 3 significant lesions. The last group (3 pts, 5.5%) were not approved for PKT. Fifty-two pts (94.5%) underwent PKT without any acurrence of cardiac death or non fatal myocardium infarction perioperatively or on follow up (6-36 months).

A M A P R I L 8

A PROSPECTIVE, BLINDED ASSESSMENT OF THE VALUE OF QUANTITATIVE DIPYRIDAMOLE-THALLIUM SCANNING IN THE PREDICTION OF PER/OPERATIVE M Y O C A R D I A L INFARCTION FOLLOWING PERIPHERAL VASCULAR SURGERY N Mamode, A McQuiston, SM Cobbe, JG Pollock, W Martin Glasgow Royal Irtfinnary, Glasgow, Scotland Perioperative myocardial infarction is the major cause of mortality and morbidity following peripheral vascular surgery. Radionuclide inmging remains the investigation of choice in assessing perioperative risk, but recent studies have questioned its value. This study aimed to prospectively determine the value of quantitative dipyridamole thallium scanning in predicting perioperative myocardial infarction in unselented patients undergoing peripheral vascular surgery. 298 consecutive patients underwent dipyridamole thallium scanning and technetium blood pool imaging prior to peripheral vascular surgery. The scan results were blinded in all but 3 patients. Patients were screened for a perioperative myocardial infarction with daily CK-MB isoenzymes and ECGs for the first 3 postoperative days. Thallium images were divided into 15 segments and perfusion scores at rest and under stress were calculated. There were 21 perioperative myocardial infarctions. Perioperative myocardial infarction correlated with reversibility score (12 v 6, p=0.0001, Mann Whitney). Left ventrieular ejection fraction was lower in those with events (3 l%[s.e.2.3]v 38%[0.7], p=0.015 TTest), but there was no difference in right ventricular fraction. Of 25 patients with a moderate or large reversible defect, 3 had events, giving a sensitivity of 14% and specificity of 85%. Quantitative radionuclide imaging is a useful preoperative ilwestigation, but lacks sensitivity.

PROGNOSIS IN PATIENTS WITH LEFT BUNDLE BRANCH BLOCK AND NORMAL DtPYRIDA/VlOLETHALLIUM-2Ol SCINTIGRAPHY. Manuel Almeida, Ant6nio Ventosa, Vitor Gil, Carlos Aguiar, Jorge Ferreira, Jogo Calqueiro, Ricardo Seabra-Gomes. Hospital de Santa Cruz/Instituto do Coraqgo. Carnaxide. Portugal. Background: The presence of complete left bundle branch block (LBBB) is commonly associated with a poorer prognosis, specially in patients (pts) with coronary disease (CAD). Outside this context a normal dipyridamole thallium-201 scintigraphy is a strong marker of a favorable outcome. Objective: To assess the prognosis in pts with LBBB and a normal dipyridamole thallium-201 scintigram. Population and Methods: Pts with complete LBBB and normal myocardial perfusion which performed dipyridamole SPECT thallium-20l scintigraphy in our center for suspected CAD between 1988-95, were followed for clinical events during at least 12 months. Results: 69 pts (36 female) with 59!-_10 yrs were followed during , 33,3_+20,1 months. There i °° were no major cardiovascular events (death, myocardial infarction). ">' o ~ Four pts had clinical o 2 4 Years 6 B 10 unstable angina. All events occurred at least 2 years after the thallium-201 scintigraphy. Conclusion: The presence of a normal myocardial perfusion with dipyridamole thallium-201 scintigraphy, in this group of lots with suspected CAD and LBBB, was associated with a very good prognosis, with a low rate of minor events, occurring only after 2 years, and without major cardiovascular events.

Journal of Nuclear Cardiology Volume 4, Number I, Part 2

Abstracts Tuesday morning, April 8, 1997

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46.51

ISCHEMIC BURDEN AND PATTERN OF LV DILATION ON POST-STRESS SESTAMIBI SPECT. C.Marcassa, M.GaUi, C.Baroffio,R.Campini, P.Giannuzzi. S. Maugeri Foundation IRCCS, Vemno, Italy.

COMPARISON BETWEEN T1-201 AND Tc-99mTETROFOSMIN NORMAL DATA BASE IN SPECT SECTORIAL QUANTIFICATION G. Tamosiunas, D. Scellier, J. Lipiecki, B. Citron, D. Mestas, J. Ponsonnaille, A. Veyre, P. Rigo, R. Itti, J. Maublant. Centre Jean Perrin, Clermont-Ferrand, France.

The relation between LV dilation on post-stress perfusion images and the amount of jeopardized myocardium was evaluated in 356 consecutive pts (58+19 yrs) with ischemic heart disease undergoing rest and exercise sestamibi SPECT. The hypoperfusion extent was quantified from polar maps of the tracer distribution. Epicardial (EP1) and endocardial (ENDO) contours were automatically drawn on mid-ventricular short axis slices, and the corresponding areas calculated. EPI and ENDO stress dilation indexes (DI) were derived as Stress/Rest area. By comparison with our normal DI values, 204 pts (57%; Gr.1) had no dilation, 123 pts (35%; Gr.2) had only ENDO dilation, and 29 pts (8%; Gr.3) had global (ENDO and EPI) dilation. Gr.3 had greater reversible (exerciserest) hypoperfusion (14+12%) than Gr.1 and Gr.2 pts! (5+7% and 10-&-_10%,resp., p<0.01). Gr.3 had also greater: ENDO DI (1.57+.38) than Gr.2 pts (1.38+.19; p<0.01). Significant ST-segment depression was more common in Gr.3 (79%) than Gr.1 and Gr.2 pts (46% and 61%, regp.; p<0.01) and occurred earlier (9.9+3.2 min in Gr.3 vs I2.4+3.9 rain in Gr.1 and 12.1 +_3.7min in Gr.2; p<0.01). Chest pain was also more frequent in Gr.3 (52%) than Gr.1 and Gr.2 (26% and 37%, resp.; p<0.01). I n conclusion, global LV dilation on post-stress sestamibi images, though less common than cavity dilation, reflects a more severe ischemia.

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Interpretation of sectodal quantification of myocardial SPECT images requires comparison of the individual sector values with normal values. We have developed a new automatic method of quantification which eventually divides the leR ventdcutar myocardium into 18 sectors of nearly identical volumes. This program was applied to two sedes of patients (10ts) with a low likelihood of coronary artery disease. One sedes involved 29 pts who underwent TI-201 stress, 4-hr redistribution, and reinjection, the other one 20 pts who had a same-day rest and stress Tc-99m-tetrofosmin protocol. There was no statistical difference between the sectorial distribution in the 5 situations. Correlation coefficients between these series ranged between 0.82 and 0.93. It is concluded that a common data base of normal sectorial values can be used for quantification of TI-201 and Tc99m-tetrofosmin SPECT images.

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46.52

COMPARISON BETWEEN TI-201 AND Tc-99mTETROFOSMIN : QUANTITATIVE ANALYSIS IN CHRONIC CORONARY ARTERY DISEASE G. Tamosiunas, V. Bourgeois, J. Lipiecki, B. Citron, D. Scellier, D. Mestas, J. Ponsonnaille, A. Veyre, J. Maublant. University Hospital, Montevideo, Uruguay.

CLINICAI, IMPLICATIONSOF MISMATCHEDREGIONAL MYOCARDIAL UPTAKES IN amTLAND 1z3I-BMIPPSPECT K. Ueshima,T. Musha, S. Hosokawa,T, Miyakawa,Y. Taniguchi, K. Nakai, K. Hiramori. Second department of Internal Medicine, Iwate Medical University, Morioka, Japan

The aim of this study was to compare the difference between the defects with TI-201 and Tc-99mtetrofosmin at rest in 24 patients with chronic coronary artery disease (CAD). We have developed a new automatic method of quantification. The left ventricular myocardium was divided in 18 sectors (sc) of nearly identical volumes. A reduction of uptake <60% of peak activity was considered as severe. TI-201 identified 260 normal sc and 172 abnormal sc, among which 62 were severe. Tc99m-tetrofosmin identified 248 normal sc and 184 abnormal sc, with 82 severe. These differences were significant (p<0.05). It is concluded that Tc99m-tetrofosmin shows more abnormalities than TI201 at rest in chronic CAD

Myocardial perfusion and fatb' acids metabolism at rest were assessed by SPECT withTI and BMIPP in 80 consecutivepatients. Mismatched regional myocardial uptakes were observed in 30 patients and classified into the following 2 groups: reduced BMIPP uptake relative to TI peffusion (B-type ; n=16, mean age, 68 years) and reducedTI perfusion relative to BMIPP uptake (T-type; n=14, mean age, 64 years). In B-type mismatch, the incidence of coronary heart disease (CHD) was 75%, 70% of which was single vessel disease. The artery perfused region in the B-type mismatch was almost always ischemia-related. Although the underlying heart diseases of the T-type dissociation were varied, 71% of the T-type mismatch was found to be related to the inferior region. The non-hypetrophied site in cases of hypertrophic cardiomyopathy (HCM) showed T-type uptake. In T-type mismatch, 80% of the CttD cases were associated with multi-vesselstenoses.In conclusion,B-type mismatchwas related to CHD, and although T-type mismatch was mainly ascribed to diaphragmatic attenuation in the inferior region in T1 scans and augmented artilhcrs in BMIPP scans, T-type mismatch was also related to myocardial ischemia in cases of CHD, and abnormal fatty acid metabolism in cases of HCM.

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T U E S D A Y

Abstracts Tuesday morning, April 8, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

46.53

46.55

99mTc-TETROFOSMIN GATED-SPECT LVEF: CORRELATION WITH ECHOCARDIOGRAPHY AND CONTRASTOGRAPHIC VENTRICULOGRAPHY. C. Di Leo, A. Bestetti, L. Tagliabue, ^D. Castini, ^M Facchini, ^C. Fiorentini, GL. Tarolo. Department of Nuclear Medicine and ^Cardiology - University of Milano - HSPaolo (Milano - Italy)

DISCORDANCY OF PERFUSION AND FATTY ACID METABOLISM IN HYPERTROPHIED HEART ASSESSED BY SPECT WITH THALLIUM-201 AND 1-123 BMIPP. H. Kobayashi, T. Nakata, K. Miyamoto, T. Sasao, and K. Shimamotn. Sapt)oro Medical University, Sapporo, Japan.

The aim of this study was to correlate LVEF values measured on stress 99mTc-Tetrofosmin images assessed with G-Spect method and those with two-dimensional echocardiography and contrastographic ventdculography. 57 consecutive pts (33 M and 24 F, mean age 60 yrs) were studied with the first two approaches; 12 of them with also ventdculography. G-Spect raw data were processed by three blinded observers; LVEF and ventricular volumes (EDV/ESV) were calculated using automatically cedars quantitative gated protocol (Germano's quantitative method). In 22 pts LVEF and ventricular volumes were determined at rest and after stress study. Results: Mean values of LVEF were: (G-Spect; X=48%+/-13 vs Echocardiography; X=49%+#13 vs Ventriculography; X=46%+/-13, p=n.s.) Pearson's analysis found a good correlation between L V E F values: (G-Spect vs Ecocardiography:r=0.85; G-Spect vs Ventdculography:t=0.85; Ecocardiography vs Ventriculography:r=0.83 p< 0.05). No significant difference was found between stress/ rest LVEF values and EDV/ESV. Interobserver variability was of 1 % (range: 0-8). Conclusion: These data show a good correlation between LVEF values calculated with G-spect, echocardiography and ventdculography. Cedars quantitative gated Spect application seems to be an accurate and reproducible tool, observer independent.

To investigate the correlation between myocardial perfusion and fatty acid metabolism in hypertrophied heart, uptakes of thallium and 1-123-1abeled fatty acid analogue, BMIPP, were assessed with SPECT in 66 patients with hypertrophic cardiomyopathy ( H C M ) , 31 with hypertension or aortic stenosis ( H T / A S ) , and 18 controls ( N C ) . Reduced BMIPP uptake relative to that of thallium, discordant appearance, in HCM patients was more frequently observed than in HT/AS or NC group ; 86% vs 55% vs 22%, respectively. Compared to HT/AS patients, discordant appearance was more common in antero apical and interventricular septal segments in HCM patients ; 23% vs 42% and 5% vs 20%, respectively. In HCM group, the discordancy was more prominent in apex ( 53% ) in patients with a n o n obstructive form and in interventrieular septam ( 3 3 % ) in patients with an obstructive form. There was, however, no significant difference in lateral walls between HT/AS and HCM . groups. Defective uptake of BMIPP or thallium was uncommon in functionally maintained AS/HT and HCM patients ((I-11%) but more frequent in HCM patients at an advanced stage showing cardiac dysfunction ( 3 8 - 5 0 % ) . Thus, assessment of myocardial perfusion-fatty acid metabolism correlation by thallium and BMIPP may contribute to identifYing the etiology and severity of hypertrophied heart.

A M A P R I L

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46.56

Nitrates T e - 9 9 m - M I B I SPECT and Dobutamine Echocardiography in Predicting Wall Motion Recovery after CABG. A.Baszko, K.B~aszyk, L.Paluszkiewicz, A.Szyszka, A.Cie~lifiski, P.Kwinecki, M. Popiel, A.Poni2yfiski, M.Gembicki, J.Sowifiski

QUANTITATIVE TOMOGRAPHY WITH Tc-99m LABELED AGENTS IN CORONARY ARTERY DISEASE: COMPARISON BETWEEN SESTAMIBI AND TETROFOSMIN.

8

Department of Cardiology, Universityof Medical Sciences, PoznaYz,Poland

A. Cuocolo, P. Sullo, A. Nappi, L. Pace, E. Nicolai, S. Cardei, F. Menna, B. Tdmarco, M. Salvatore. Universit& Federico II, Napoli, Italy.

To compare the efficacy of Tc-99m-MIBI SPECT at rest (Rest-SPECT) and after nitrates administration (NTG-SPECT) with low-dose dobutamine echocardiography (DE) in predicting contractile recovery, we evaluated 20 pts. with left ventricular dysfunction. Perfusion (PI) and contractility (WMI) were assessed before, and 3 months after CABG. Of 77 asynergic segments, functional recovery was observed in 37 (48%) and was paralleled by perfusion improvement. Viable regions had lower perfusion defect at rest and after NTG administration (PI: 2.73+1.41, 2.41+1.26 vs. 3.69+1.57, 3.08_+1.33, p<0.001) and less contractile dysfunction (WMI: 2.49+0.51 vs. 2.85_+0.58, p<0.01). The sensitivity and specificity in predicting contractile recovery were 68% and 75% for DE, 76% and 58% for Rest-SPECT (preserved perfusion), 43% and 58% for perfusion improvement at NTG-SPECT, 81% and 42% for preserved perfusion at NTG-SPECT. We conclude that dobutamine echocardiography and preserved perfusion of asynergic regions at Tc-99m-MIBI SPECT (at rest or after NTG) are useful in predicting functional recovery after revascularization, while perfusion improvement after additional acquisition after nitrates has lower value.

Tc-99m labeled myocardial perfusion agents are widely used for the noninvasive detection of coronary artery disease (CAD). The aim of this study was to directly compare the results of Tc-99m sestamibi and Tc-99m tetrofosmin tomography in 32 patients (27 men, mean age 51+9 yrs) with suspected CAD. All patients were submitted in separate days to exercise-rest Tc-99m sestamibi and Tc-99m tetrofosmin tomography (370 MBq iv at peak exercise and 1110 MBq iv at rest 4 hours later). Regional tracer distributions were quantitatively measured in corresponding segments. Seven patients had normal coronary vessels, 11 one-vessel, and 14 multivessel CAD (>50% diameter stenosis) on coronary angiography. The quality of images judged visually was comparable with the two tracers. With the limits of normal as 2 SD below the mean of gender-matched normal volunteers, Tc99m sestamibi identified 23 of 25 (92%) and Tc-99m tetrofosmin identified 24 of 25 (96%) patients with CAD (P=ns). Tc-99m sestamibi identified 32 of 46 (70%)and Tc99m tetrofosmin identified 33 of 46 (72%) stenosed coronary arteries (P=ns). The quantitative severity of perfusion defects was similar for the two tracers. Thus, quantitative exercise Tc99m sestamibi and Tc-99m tetrofosmin tomography provide similar information in the diagnosis and localization of CAD.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

46.57 EFFEC]S OF AFIERLOAD Ik/CP,FJ',SE CN THALL!L~,-2~ SCINTIGRAPHY

ANO ~ A R I S O N Wi~-iCON~NhONAL [~XER~ IMAGI~IG. Athonassios Antonopouios. Dimitrios Nikolopouios. Evangelos Geor~ou, Michael Kyriokidis, Povtos Toolouzos. CharalQmbos Proukakis, Oept o f Medical Physics and Cardiology. Athens University. Athens. Greece, Shoe d!erl0o::i increa~ causes let! venh'~d~ wo~ s!ress as wel~ as oxygen cc~vJr~otba, we hyp0lhes~zed~h~, c~ ~ ...~0#N &gent such as pheny~p~'k~. (l~) may polentidly provoke ctx.,~~c~in myocor~ot t_~.'ffu~;on,Thecim of this stunt was to evobat=, o),he o.ec,s of, on ,,-~0, (,/1)seln,t~,.q~hymd b) ,0 c0mF~ ~ J-201 conventionc~e×erd~e (C} with P-schlicrc~hv res@ 40 pat;enls with &')cumenled CAD by corOndy ,:~o~ophy ( 7 pis ~'[lh ,.~,~a. 22 pts with old Iv! orct 11pfs with c~c,r~ CAD) c',d~=!56*Syrs w~e ;_,~2,.*dedh ,:,~ ..qudy.A cdor:_~y sleno~s;,70% was c,..',nslderOdsi£#fiConL h eQch one of them P (0.invglmi) was inr~ed a! a role of O.8~/,,'T'Yt,Jn,f~ mere blood' procure (BP)hcre~ed at approxtnately ~ % from baseline,byeS.No major cacDc events were deified wilh P-infusbr~One ~ after the b e g ~ g of Pn/usion,2 mCi of TI wo~ njecfed ar:d the nfu~n of # was tudhe~"continued for kS,m~, 1Vschlk,Jc,~hy was 0edonr~d 2mh oiler T[ ~ieclion o~'id 44','s ~O~d.~ge~ re~ts were eompa,'ed with those of o C performed 4 days late~. P produces shik:r rLmbef cA lolal defects (145)c.~-npored to C (156) (p
Abstracts Tuesday morning, April 8, 1997

46.59 Dual l ~ o p ¢ Myocardhil Perfmion Tomography: Separate Versus Shnultaneous Rest TL~*t/Stress"FeT M SestamibL Waheed Radwan; Selama Husslen and Sherlf Mokhtar Critical Care Medicine, Cairo University, Egypt To *mess the degree of isotope eresstalk in dual isotopetomographic studies, and Io compareit with separaterest TL2orstressTc~ images, the following 2 days imagingprotocolwas appliedwhere in day 1, "re~emsestamibi(15 mCi) was injected at peak exerelsefollowed by SPECT 30 rain. later applyingthe usual Tc9~ window (140~20% Key). TL2or (3 mCi) was then injected at rest and SPECT acquisition was performed 30-45 miv_ later using various dual isotope energy

windows. On day 2, adaseof2.SmCiTL2Omwasinjecteddurlngrestfellowedby SPECT 20-30 min. later.

Twlnty patientsknewnto have IHD, HealedQ wave M1 have been subjectedto this protocol whichallowedus to: 1. Comparedual and virginstresssestanuT~iSPECT images. 2. Comparedual and virginrest TL TM SPECTimages. Analysis of results entailed dividing the LV into 20 segmentswiththe degree of perfusien expressedon a scaleof 0-4 and a final scorewas givenfor the whole LV. Results: comparing the virgin sestamibiwith the dual sestamibi(contaminated) images revealed a mean difference of 1.3 segmentsand a score differenceel3.4. Meanwhile comparing the virgin TLTM with dual images shewed a mean difference of 2.8 segmentsanda score differenceof 7.3, Coneh~ian:

1. Using various acquisition windows and processingtechniquesavailablein cur computer system(differentfilters,filterorders, successivefilterlng,background and scattersubstractien)failedte bringcontaminatedup te virgin images. 2. The degreeefcrosstalk of To99~ into lhn TL2°1windowis higherand affectsthe dual TL201 images eousiderably, despitethe use ofvarieus filteringtechniques and ecquM'donwL-~do~.

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49.1

M Y O C A R D I A L U P T A K E OF T H A L L I U M A N D TC-99M TETROFOSMIN : A DETAILED COMPARISON.

IDENTIFYING PATIENTS WITH ACTIVE C O R O N A R Y D I S E A S E IN A N E M E R G E N C Y DEPARTMENT OBSERVATION UNIT

G.McCurrach, LProsser, S.Woldman, A.McQuiston, W.Martin, I.Hutton Dept. Nuclear Cardiology, Glasgow Royal Infirmary, Scotland Tetrofosmin Tc-99m has been proposed as an alternative to thallium-201 in the assessment of myocardiai perfusion. This study compared the percentage myocardial uptake of both agents at rest and at stress in separate groups of patients being routinely assessed for chest pain. In addition, myocardial uptake of tetrofosmin was assessed dynamically post injection both at rest and exercise. The uptake in the myocardium was then calculated as a percentage of the injected dose, and was found to be similar at rest : tetrofosmin 0.32 + 0.12 (n=30) ; thallium 0.33 + 0.12 (n=l 5). However at stress myocardial uptake was significantly higher for thallium (p < 0.05) : tetrofosmin 0.24 + 0.17 (n=20) ; thallium 0.54 + 0.25 (n=50). From the dynamic images we estimate that: at rest, 57 % (+ 23) of maximal tetrofosmin uptake is achieved by 1 minute, 83 % (+l 1) by 2 minutes and maximal uptake by 5 minutes : on exercise, values were similar, with substantial blood pool activity apparent at 3 minutes. In conclusion, uptake of tetrofosnain on exercise is significantly lower than that of thallium whilst at rest the two agents show similar myocardial uptake.

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P a u l R . B u r n s , A r i f S h e i k h , G e o r g e R. M c K e n d a l l , S t e v e n R e i n e r t , L y n n e L. J o h n s o n . R h o d e I s l a n d Hospital, B r o w n University, P r o v i d e n c e , R I . USA

The goal of this study was to evaluate non-invasive testing and clinical variables to identify pts f r o m an ER observation unit (EROU) with active CAD. Pts with intermediate suspicion for unstable angina (UA), were admitted to E R O U . After 2-3 n e g C K - M B ' s pts underwent E C G stress with sestamibi S P E C T imaging. There were 138 pts, 71 M, 67 F with m e a n age o f 52 + 13; and 80/138 had abnl rest ECG's. U s i n g clinical, historical and E C G variables pts were further classified into low, m e d i u m , and high suspicion for U A (clinical index). This index and results of stress parameters and scans were evaluated. Only 8/138 ultimately had active C A D (AD) and required hospitalization. T h e clinical index identified 41/138 pts as high suspicion but only 5/8 with AD. Unlvariate logistic regression analysis was used to calc odds ratios on two continuous (exercise stage, s u m severity score SSS) and three categorical variables. variable n value odds ratio clinical index 0.16 1.97 ex ECG 0.0001 18.33 +scan 0.0001 19.9 ex stage 0.017 0.28 SSS 0.002 1.08 There is need to refine criteria for identifying CP pts who need further testing and for identifying w h i c h pts need scanning.

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T U E S D A Y

Abstracts Tuesday morning, April 8, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

49.2

49.4

VALUE OF REST Tc-99m SESTAMIBI IN THE EMERGENCY DEPARTMENT(ED) P. Lizotte, M. Callaham, M. Dae, C. Wolfe, T. Chou, E. Botvinick, UCSF, San Francisco, CA

CONTRASTECHOCARDIOGRAPHYVS. PERFUSIONIMAGINGTO DETECT STUNNED MYOCARD1UMIN PATIENTSTREATEDWITH PRIMARYPTCA

R.Scia~h, L.Bolognese, P.Buonamici, G.Cerisano, C.Olianti, S.Sestini, G.M.Santoro, P.F.Fazzini. Nuclear Medicine, University of Florence ; Florence, Italy.

We studied with test Tc-99m Sestimibi(MIBI) 34 random patients(pts) with suggestive pain and nondiagnostic EKG admitted for rule out MI with follow-up(FU) for up to 14 months(mean 9). ECG was abnormal in 26 and coronary history was known in 8. In 2_7_7p_$_~with normal ED MIBI, 24 were pain free at MIBI injection, a mean of 4 hours after pain resolution. F U stress MIBI was abnormal in 2, one requiring coron~u'y angiography(SCA) and PTCA. One pt with apparent "prior MI history" had no ED MIBI abnormalities with subsequent normal SCA. No ischemic events were noted on FU and in 14 another diag,aosis evolved. Evaluation cost $2979/pt. In 7~_~ with abnormal ED MIBI, 1 with MI, 5 were pain fi'ee at MIBI itliection a mean of 3 hrs after end of symptotns. ED MIBI brought immediate SCA in 4 and PTCA in 2 with augmented medical therapy with FU in 3. Stress MIBI in 3 pts brought PTCA in 1. ED MIBI defect exceeded that of recent stress M I B I in 3 pts. Evaluation cost $2996/pt. In these pts MI was rare. The sensitivity of ED MIBI was maintained after pain resolution (p<0.13). Abnormal ED MIBI diagnosed acute ischemia quickly. Normal ED MIBI excluded acute ischemia and generally CAD. If pts with normal scans had not been adnqitted, $39,501 could have been saved, with no harm.

We tested whether the demonstration of reflow within the infarct zone by means of contrast effect (CE) in two-dimensional echocardiography could be used in alternative to perfusion imaging as a marker of tissue salvage with potential functional recovery (stunning) after acute myocardial infarction. In 26 patients, CE was evaluated immediately before and after primary PTCA and graded 0 (= absent), 0.5 (= intermediate) o1" 1 (= homogeneous). Reflow was defined as increase of CE grade in post-PTCA compared to prePTCA images. Quantitative Sestamibi SPECT was collected 1 week later to assess myocardial perthsion (normal if activity > 60% of peak). Stunned myocardium was defined by wall motion improvement at 1-month follow up. Reflow was observed in 29 out of 47 asynergic segments within the infarct area with grade 0 - 0.5 pre-PTCA CE ; normal perfusion was found in 22, and [hnctional recovery in 17. Thus, the lbllowing results were obtained : -. CE p SPECT Sensitivity 82% 0.43 65% Specificity 13% < 0.0005 60% Accuracy 38% < 0.05 62% In conclusion, CE is slightly more sensitive, but significantly less specific and accurate than pcrfusion imaging. So far, CE does not appear a reliable alternative to perthsion imaging to define the extent of salvaged stunned myocardium after primary PTCA.

49.3

49.5

CORRELATION OF SERUM MARKERS AND ACUTE MYOCARDIAL PERFUSION IMAGING MD Duca, RS Morris, AH Wu, A Ahlberg, Y Feng, MP White, GV Heller. Hartford Hospital, Hartford, CT U S A

INCIDENCE AND EXTENT OF DENERVATED MYOCARDIUM IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION TREATED WITH REPERFUSION THERAPY I. Matsunari, P. Barthel, F. Bengel, A. Hierl, B. Dzewas, F. Hartmann, G. Miinch, G. Schmidt, M. Schwaiger. Technische

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UnversitiitMiinchen, Germany Serum markers and acute Tc-99m SPECT myocardial perfusion imaging (MPI) are useful in diagnosing myocardial ischemia/infarction as the etiology of chest pain, but less data on correlation is available. Pts (70) with chest pain had acute MPI and baseline serum markers: troponins T and I (TnT, TnI), creatinine kinase (CK) and CKMB. N Any + TnT/TnI TnT/Tnl/ Total marker + CKMB + CK + (-) MPI 48 7 1 3 7 (+) MPI 22 6 3 5 3 Abnormal baseline markers were rarely associated with normal MPI (15%). Further evidence of CAD (by stress MPI, MI by enzymes, or angiography) was seen in 79% of pts with abnormal MPI vs 58% of pts with positive baseline markers. Conclusion: Acute myocardial perfusion imaging has a higher sensitivity and identifies patients with C A D more often and earlier than baseline serum markers

Prior MIBG studies have suggested that regional denervation may occur in patients with acute myocardial infarction (MI). The purpose of this study was to investigate the incidence and extent of MIBG abnormalities in patients undergoing reperfusion therapy. 55 consecutive patients with first MI who had undergone PTCA or thrombolysis had MIBG (5 hr) and rest T1 SPECT images. Image analysis was based on a semiquantitative polar map approach. Defect size (DS) on the MIBG or TI images was measured for the left ventricle((LV) using a threshold of 50% of peak counts and expressed as %LV. Mismatch was calculated as differences in defect size between TI and MIBG images. MIBG DS was larger in 96% (53/55) of patients, and 2 patients without mismatch had T1 DS <2%. Notably, 17 of 30 patients with 1-vessel disease (SVD) had MIBG defects exceeding the infarct vascular territory, while T1 defects were confined to the infarct territory in all but 1 patient. There was no correlation between the extent of mismatch and either the time to revascularization or the extent of coronary artery disease based on angiography. Thus, the extent of MIBG abnormality was greater than that of T1 in all patients with TI defects over 2% of LV, suggesting that sympathetic nerves are more sensitive to ischemic injury than myocardial tissue. However, the extent of MIBG defect was not confined to the infarct vascular territory in 57% of patients with SVD, suggesting that factors other than ischemia determine alterations in myocardial MIBG uptake.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

50.1 ARBUTAM/NE 1N GATED BLOOD POOL RADIONUCLIDE VENTR/CULOGRAPHY(RNV): COMPARISON 'WITHPHYSICAL STRESS TEST R.Aarisch, J.Holzinger, D.L. Munz Clinic of Nuclear Medicine~ Charit~ Hospital, Humboldt University Berlin, Germany RNV at rest and under bicycle stress test conditions is well established in our clinic. Aim ofonr investigation was the direct comparison between this physical stress test and pharmacological test by arbutamiae, using a computerized closed loop delivery system (GEN$IA Europa). Patients: 20 pts, 16 male and 4 female, wiO known (n=6) or sus'tx~ted (n= 14) CAD without actual clinical symptoms such as angina peetoris or signs of congestive heart disease. Methods: RNV at rest, followed by step,vise bicycle stress test. We doettmanted the following parameters: global and regional left vantricular ejection fraction CLVEF),contractility parameters, and the basis information's heart rate (HR), blood pressure (BP) and ECG. After restoration of HR and BP on rest level we continued by arbutamine stress test. On different FIR levels, corresponding to the steps of physical stress test, we registered the same (above mentioned) parameters. Results: 1. At comparable HR. levels the LVEF had significantlyhigher values under arbutamine compared to physical stress. 2. During arbutamine Stress all pts demonstrated increasing LVEF - even 5 pts with decreasing LVEF uncl~rergometric stress. Conclusions: 1. The intensive positive inotrophic effect of arbutarame seems to prevail the perfusion-related regional wall motion disorder and makes it difficult to detect slight and moderate forms of CAD. 2. Arbutamine, used in RNV, may underestimate the ischemia frequency, but can produce evidance ofmyecardial viability by proof of inotrophic reserve.

Abstracts Tuesday morning, April 8, 1997

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50.3 SCINTIGRAPHY WITH 9'~mTc-D-GLUCARIC ACID IN PATIENTS WITH ACUTE MYOCARDIALINFARCTION G Mariani, G Villa, PF Rossettin, C Motta, P Spallarossa, G Calcagno, GP Bezante, C Brunelli, S Caponnetto, KY Pak, J Narula, BA Khaw, HW Strauss. Nuclear Medicine and Cardiology, University of Genoa; Genoa (Italy); MTTI, Inc.; Frazer, PA; Stanford University; Stanford, CA (USA). ~9"Tc-D-Glucaric acid (T-GLA) localizes in areas of experimental myocardial infarction within 1 hr of vessel occlusion. We now report the initial clinical and imaging experience in patients (pts) with AMI using this new agent. Sixteen pts (13 men, 3 women) with AMI were injected with T-GLA i.v. (900-10130 MBq) within 2-41 hr of onset of chest pain, and planar images were recorded 1-2 hr later. Perfusion with -~°lTI or 99mTc-MIBlwas assessed in all pts, and 13tt6 pts had coronary angiography within 10 days. Clear T-GL~ uptake at the site of AMI was observed in 11/16 patienls, slightly overestimating the size of the actual AMI v e r s u s 2°~Tl or 99rnTc-MIB[. T-GLA localized in either reperfused or non-reperfused AMI equally efficiently. In the 5 negative pts, T-GLA had been injected over 9 hr after the onset of chest pain, after peak serum CPK levels had been reached. The intensity of T-GLA uptake was not correlated with either the size of AMI and/or peak serum CPK levels. T-GLA can identify zones of acute ischemie injury of the myocardium leading to myocardial necrosis, when injected within 9 hr after onset of chest pain (before peak serum CPK levels) in patients with AMI. It provides thus a very early delineator of AMI and supplements other infarct-avid agents.

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50.2

50.4

DOBUTAMINE Tc-99m SESTAMIBI GATED SPECT: New Method for Myocardial Viability Assessment in Patients with Left Ventricutar Dysfunction and Coronary Artery Disease. N.Zafrir, N.Avraham, J. Sulkes, S. Sclarovsky, Rabin Medical center, Beilinson Campus, Israel

Q U A N T I T A T I V E S C I N T I G R A P H I C A S S E S S M E N T OF PERFUSION DURING R O T A T I O N A L A T H E R E C T O M Y

This stu~" im,estigated the use of dobutamine (DOB) ,vith sestamibi GATED SPECT (GS) imaging, a nee,, method which enables us to assess myocardial ,,iability concomitantly by perfusion and contractile reserve. Twenty-one patients (pts) with triple coronary artery disease and severe left ventricular dTsfunction were studied. All were intravenously injected with 30mci of Tc-99m sestamibi for first-pass acquisition (mean EF 28+5%). One hour later resting GS imaging was performed followed by infusion of DOB, starting dose 51.tg/kg/min, followed by 101.tg/kg/min for 5 rain and throughout imaging . After processing, the myocardium was divided into 5 territories (T):septum, apex, anterior, inferior and lateral. Each was assessed for normal perfusion (>80% uptake), abnormal (AB)-viable (80-50% uptake) and AB-non,4able (<50% uptake). Wall motion (WM) was assessed visuaUy as normal, AB-viable if it improved with DOB and &B-nonviable if it did not. Interobserver variability was 8%. The agreement between WM and perfusion was 64%. Nineb,-one T (87%) had AB WM, of which 48 (53",6) showed WM improvement with DOB and 57 (63%) were considered viable by perfusion (NS). Of the latter, 43/57 (75%) had W/vl improvement with DOB, in contrast to only 5 of 34 T (15%) considered nonviable by. perfusion (p<0.001). Conclusion: DOB GS imaging may be a useful method to assess myocardial viability both by perfusion and contractile reserve. However, its predictive value regarding functional improvement after revascularization needs to be explored

J. vom Dahl, K.-C. Koch, E. Kleinhans, S. Ninnemann, H.G. Klues, G.Schulz, M. Sigmund, U. Biill, P. Hanrath. University of Aachen Hospital, Aachen, Germany Myocardial hypoperfusion during high-frequency percutaneous transluminal rotational atherectomy (PTRA) has been discussed to result from microvascular obstruction. To evaluate the extension and severity of this phenomenon, 34 patients (pts, 13 type B2, 21 type C lesions) were studied by Tc-99m sestamibi SPECT at rest before (preR), during PTRA (R) with SPECT after 90 rain, and after 2 days (postR). Visual analysis revealed transient perfusion defects in PTRA regions in 31/34 pts. For quantitation, the myocardium was divided in 24 regions and--perfusion expressed as % of maximal sestamibi uptake preR. Transient perfusion defects below normal-2.5SD were observed in 3.1+_2.4 regions/pt. Baseline perfusion in the PTRA vessel territory was 74+15%, decreased to 55+14% (p<0.001) during PTRA, and normalised to 74+16% postR (p<0.001 vs. R). The only procedural factor influencing the extent of defects was the degree of lesion calcification (4.2+2.5 regions in calcified vs. 2.3+2.0 regions in non-calcified lesions, p<0.05). However, preliminary observations in additional 7 pts receiving periproceduraUy platelet antibody c7E3 (ReoPro TM) revealed no defects (68+10% preR, 64+9% R, 73+12% postR; p=ns). Thus, SPECT during PTRA may prove useful as a diagnostic tool to study therapeutic strategies to reduce PTRA induced "low flow".

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Abstracts Tuesday morning, April 8, 1997

50.5

T U E S D A Y

TC99M SESTAMIBI PERFUSION SCINTIGRAPHY IN PERIPHERAL ARTERIAL OCCLUSIVE DISEASE RELIABLY PREDICTS POSITIVE EFFECTS OF PROSTAGLANDIN E2-ANALOGON A.Bentrup, C.Lucke, D.Hartung, I-I.J.Otto, H.U.Klein, A.Schmidt. Otto-von-Guericke-University Magdeburg, Germany. Pharmacological treatment with the prostaglandin E2analogon (PGE) i.a. is a widely used therapy to improve peripheral perfusion. The aim of this study was to verify the effects of PGE on peripheral arterial circulation using Tc99m Sestamibi perfusion scintigraphy. The perfusion of 20 lower legs in 10 pts (5 female, 5 male; mean age 75+9 years) with angiographieally proven peripheral artery disease was investigated before, during, and immediately after a series of intraarterial infusions with PGE. 3-10 rain and 4 h after compression of the lower legs and i.v. injection of 10 mCi Tc99m Sestamibi, dynamic and static images of the lower legs were obtained. Count rates were measured in regions of interest including the entire lower legs. Results were compared in each patient with transcutaneous Doppler ultrasonography and clinical improvement. The mean increase in perfusion of the dominant diseased legs was 32% (p < 0.007) and 28% in the other legs (p < 0.05). These findings correlated in 89% with the clinical improvement (p<0.05). Conclusion : Tc99m Sestamibi perfusion scintigraphy can quantitatively estimate the augmentation of blood supply under treatment with PGE, and it correlates well with the clinical outcome.

Journal of Nuclear Cardiology January/FebruaE¢ 1997, Part 2

51.2 LUNG TL UPTAKE AND DIASTOLIC FUNCTION IN PATIENTS WITH SEVERE LV DYSFUNCTION.

C.Marcassa, M.Galli, A.Imparato, PL.Temporelli, P. Giannuzzi. S. Maugeri Foundation IRCCS Veruno, Italy. Resting T1 lung/heart ratio (L/H) correlates with LV filling pressure as well as Doppler-derived deceleration time (DT) of early filling (E). We compared the T1 L/H and the LV diastolic function from mitral Doppler in 24 pts (64+10 years) with severe LV dysfunction (LVEF 28+10%). All pts underwent a 3-view planar rest: redistribution T1 and 2D-Echo studies, From mitral Doppler E and late (A) filling velocities, E/A ratio and DT were calculated. A significant linear relation was observed between LFrI and E/A (r=0.69; p<0.001) as well as L/H I and DT (r=-0.61; p<0.001); an even stronger, inverse, relation was found between L/H and A (r---0.81; p<0.001; Fig 1). An abnormal (>0.54) L/H identified 80% of pts with a 01 . . . . restrictive filling pattern 0# ~ 0,s' (DT<120 msec & E/A>2). In conclusion, L/H is closely correlated with Doppler indexes of LV diastolic filling dynamic; an abnormal L/H is hilly oredictive of restrictive oattem. 150 " k

Fig 1

J'x Q

I.. 1 .'iX. .

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51.1

51.3

RADIONUCLIDE-BASED SELECTION FOR MITRAL SURGERY IN HIGH RISK PATIENTS WITH NONISCHEMIC MITRAL REGURGITATION D. Wencker. J.S. Borer, C. Hochreiter, R.B. Devereux, M.J. Roman. P. Kligfield, P. Supino. Cornell Medical Center, New York, NY. USA

EFFECTS OF EXERCICE REHABILITATION ON CARDIAC NEURONAL FUNCTION IN PATIENTS WITH HEART FAILURE : A 123I - MIBG STUDY.

High imminent mortality risk in chronic non-ischemic mitral regurgitation (MR) is best predicted by subnl right ventricular(RV) ejection fraction (EF) and also by subnl left ventricular(LV) EF. However, survival benefits of mitral valve surgery (MVS) in such high risk pts are not known, and predictors of their late post-MVS survival are unclear. We prospectively followed 14 consecutive high risk pts who had echo and rest(r) and exercise(ex) radionuclide cineangiography before and after MVS (av 9yr postop tollow-up) and compared results with 9 consecutive contclnporaneous non-operated high risk pts. Of 14 MVS pts, 4 have died av 8 yr postop; only pre-op RVEF < 20 % (r, p =. 03; ex, p =. 05 ) identified non-survivors. Of 9 non-MVS pts, 8 died(p<.05 vs MVS); mortality also was higher than in MVS pts when groups were matched for pre-op LVEF (p=.0001), and tended to be higher when matched for RVEFex<20%(p=.09). In high risk MR pts, radionuclide-based RVEF can best identify pts with excellent long term survival if operated.

D. Agostini, E. Lecluse*, G. Babalasi**,A. Belin*, A. Manrique, P. Scanu*, M. Massetti**, G. Grollier*, JC Poticr*, G. Bouvard. Departments of Nuclear Medicine, Cardiology*, Cardiac Surgery**, Caen, France. Cardiac heart failure is associated with sympathetic dysfunctiun. Exercice rehabilitation (ER) improves clinical performances of patients with CHF. Althoughthis improvementis primarily due to periphericaladaptations,the cardiac neuronal functionhas not been well defined. The aim of the stud)' was to determine whether ER could induced changes in cardiac neuronal function assessed by 123I -MIBGplanar scintigraphy.We prospectivelystudiedtwice 14 pts (tiM, 3F, 47+8.5 yrs old) with ischemic (12) and dilated (2) cardiomyopathy who underwent radionuclide ventriculography, MIBG scintigraphyand exercicetesting (Bruce protocol)beforeand after ER. ER consisted of muscle exercice and enduraucy training (3 times per week, 60 sessions).Therapy consistedof diuretics and an~iotensin converting enz3,m-inhibitors,After an IV of 185 MBq of]23I -MIBG,a chest anterior viex was acquired 4 hours later on a gamma-camera.Titus, heart to mediastinumratio activib' (I-IMR) was measured as previously described. ER improved NHYA functional class from III to II, exercicctime (504+190 vs 649+125, p<0.05), peak power output (129+69 vs 216+47 W, p<0.001). LVEF did not chmlge (23+9% vs 21+10%, NS). HMR improved from 135+19 to 156+25,p<0.02. In conclusion, ER induces improvement of cardiac neuronal function without negative effects on cardiac contractility.

Abstracts Tuesday morning, April 8, 1997

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

51.4

52.1

RADIOLABELED ANTIMYOSIN ANTIBODY AS AN INDEX OF FIBROSIS IN AORTIC REGURGITATION P. Lu,S. Goldfine,P. Zanzonico,E.M. Herrold,N. Magid, J.S. Borer. Cornell Medical Center, New York, NY, USA

WOLFF-PARKINSON-WH1TESYNDROME: EVIDENCE OF IMPAIRED RIGHT VENTRICULARFUNCTION J Prosser, A Ng, G McCurrach, W Martin, I Hutton Dept. Medical Cardiology, Glasgow Royal Infirmary, Scotland

Marked myocardial fibrosis invariably accompanies, and may cause, myoeytolysis when chronic experimental aortic regurgitation(eAR) leads to heart failure(CHF). Myocardial uptake of In-11 l-labeled antimyosin antibody (AA) in vivo by external imaging is greater in chronic(c) eAR than in subacute(s) eAR or normal. To validate AA uptake as a measure of fibrosis in AR, we defined relative heart AA concentration vs histologic fibrosis score in 30 rabbits (19=surgically induced severe AR, 11 =control) given 11.5mCi l n - I I I - A A Fab Fragment (Myoscint) i.v. and sacrificed 48 hr later. Fibrosis score in seAR (3-5 wks of AR; n= 11, 0 with CHF) was 6.6 vs 6.2 tot age matched controls (n=5, NS); in ceAR (98:128 wks of AR; n=8, 0 with CHF) score was 8.3 vs 5.3 for age-matched controls (n = 6, p < 0.1). Among AR and age-matched controls, relative heart AA concentration correlated with fibrosis score (r=0.6,p=.03) despite absence of CHF or severe fibrosis. In eAR, myocardial I n - l l l - A A uptake quantitatively reflects myocardial fibrosis, probably pathogenic lot myocardial damage, before CHF occurs.

Gated radionuclide ventriculography (RNVG) is used to assist in the localisation of the accessory conduction pathway in , patients with the Wolff-Parkinson-White syndrome (WPW). It also allows accurate assessment of left and right ventricular function - data which has not been studied in detail in this group of patients. This study was a detailed comparison of right and left ventricular function in WPW patients and a control group. Twenty two WPW patients underwent RNVG prior to radio-frequency catheter ablation. A further 18 patients with no previous myocardial infarction and normal wall motion on routine assessment, were selected from patients studied by RNVG. Left and right ventricular ejection fractions were calculated using a manual, single ROI technique, previously validated in our institution. No difference in left ventricular function between the two groups was observed; mean LVEF was 43.4% (S.D=9.4) for WPW patients and 44.6% (_+6.1) for patients in the normal group. However, there was a significant difference in right ventricular function; mean RVEF = 31.4% (_+8.4) for WPW patients compared to 43.9% (+6.5) for normal patients, (P<0.0001). The underlying mechanism for this impairment of right ventricular function is unclear and the effect of rf ablation requires further investigation.

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A M 51.5 GAS EXCHANGE ABNORMALITIES IN PATIENTS WITH CONGESTIVE HEART FAILURE (CHF) CORRELATE WITH INCREASED LUNG DENSITY. Luis I. Araujo, Evan Loh, Joseph Maffei, John Reilly, Abass Alavi, Joseph R. McClellan. University of Pennylvania, Philadelphia, PA Gas exchange abnormalities in patients with CHF may be related to an increase in lung water. We correlated results from eardiopulmonary exercise testing with extravascular lung density (EVE)) obtained with SPECT in seven patients with CHE. SPECT transmission (T) and blood pool (BP) images were acquired with a Picker 3000 XP scanner after exercise. Total lung density (TLD) and blood volume (BVol) were measured by analyzing regions of interest over the lung segments of normalized T and BP images. EVD was calculated by subtracting Bvol from TLD and correlated with ventilation and gas exchange parameters. Linear regression analysis was used to correlate EVD with oxygen uptake (VO2), total ventilation (VE) and the ratio of ventilation to expired CO2 (VENCO2). Results: There was no correlation between rest VF_JVCO2 and EDV; VEmax and EVD; or VO2max and EVD. There was a correlation of EVD with VE/VCO2 max (r2=0.86, p=0.01). C o n c l u s i o n : This noninvasive analysis demonstates that worsening exercise V/Q mismatch in patients with CHF is related to extravascular density which reflects greater lung water content.

52.2 PREDICTION OF CARDIAC DEATH AFTER REVASCULARIZATION BY SERIAL RNA: A COMPARISON WITH CLINICAL AND CATHETERIZATION DATA Salvador Borges-Neto, Leslee Shaw, Karen Kessler, Edward Morris and R.E Coleman. Duke University Medical Center, Durham, USA. Rest and exercise radionuclide angiocardiograms (RNA) were obtained in182 patients before and after CABG. Cox proportional hazards regression analysis was used to identify the independent predictors of the 44 cardiac deaths which occurred during follow-up of 12 years after CABG. Although the exercise ejection fraction (EF) before and early after CABG related to subsequent death (X ~= 10.8, p = 0.001 and X z= 7.4, p=0.006, respectively), the late post-operative exercise EF was the strongest predictor (X 2 = 13.9, p =0.0002), Moreover, the late exercise EF contributed with significant information above and beyond that provided by clinical and catheterization variable (p < 0.0001). Therefore, serial exercise RNA should be regarded as as important noninvasive adjunct to postoperative evaluation of CABG patients.

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Abstracts Tuesday morning, April 8, 1997

Journal of Nuclear Cm'diology January/February 1997, Part 2

52.3

52.5

HYPERTHYROIDISM INFLUENCI=S LEFT VENTRIGULAR EJECTION FRACTION MEASURED BY RADIONUGLIDE VENTRICULOGRAPHY

ANGIOSCINTIGRAPHY OF THE RIGHT VENTRICLE: THE OPTIMAL ACQUISITION PARAMETERS FOR MULTIHARIVIONIC FOURIER ANALYSIS. D. Daou, R. Lebtahi, M. Faraggi, Y. Petegnief, D. Le Guludec, Nuclear Medicine Department, Bichat Hospital, Paris, France. Multi-harmonic Fourier phase analysis (H3) is useful in angioscintigraphic studies, particularly for localized right ventricular abnormalities. The aim of our study was to define in normal pts, the optimal acquisition parameters for an homogeneous right ventricular H3 histogram, allowing best separation between normal and abnormal studies: number of frames/cardiac cycle and number of counts/frame. Parameters used for characterizing histogram homogeneity were: standard deviation of the phase histogram (sd), shift between the first or last mean 5% and the mean of the H3 phase histogram (delta 5%,delta 95%). 10 pts had a listmode acquisition. ECG-gated studies were reconstructed with 16, 24 and 32 frames/cycle and similar counts/frame: 400 kcounts/frame. frames/cycle 16 24 32 ds phase 21±5' 34-*-6' 44±4' delta 95% 32±!5' 564-22' 484-40 delta 5% -304-16° -55±19 ° -82+31 °

R,Cze~-,z'mski, M.Ruchela, M.Gryezy6ska,J.Sowifiski, M.Gembicki

T U E S D A Y

Tachycardia and hyperkinetic circulation belor,,g to the major signs of hyperthyrcidisrn. The elm of our study was to evaluate the effect of hyp~.~yroidism on the global contractility of the left ventricle and to assess whether effective treatment of hyperthyroidism can improve presumably changed cardiac function. 42 patients (36 women end 6 men) aged between19 and 66 yeats (mean age: 40.9 yrs.) with hyperthyrd,dism due to Graves' disease or to~c nodular geltre were included in the study. All patients displayed clinical features of hyperthyroidism c o n f i ~ by elevated T3 and T4 end decreased TSH levels. In order to measure I~'t ventriculer ejection fraction (LVEF), radionuclide ventdculagr~hy (RNV - gated technique) was performedtwice in eech patient: at rest and during exercise on a supine cyclcergometer.The same procedure was repeated after 6-8 months in a subgroup of 15 patients aged from 28 to 56 yrs. (mean age: 41.7 yrs.) who became euthyrcid (no signs of hyperthyroidism and normal 3"3, T 4 and TSH levels) after radioiodine or thiamazote treatment. RNV was performed with Diacam gammacamera by Siemens with the use of Tc99m (740 MBq) end Sn-pyrophusphate. In the whole group of hyperthyroidpatients, mean resting LVEF was 59.5+12.7°./, and mean LVEF during exercise was 58.8-J:14.5%. in 5 patients, the ~ c i s e LVEF was >10% higher then the resting value and in 5 patients, it was >10% lower than LVEF at rest. In the remaining 32 patients the difference between exercise and resting LVEF was between -10% end +10%, regarded as insignificant. We did not observethe typical increase of LVEF during exercise. In the subgroup of 15 patients who were examined again after treatment, resting and exercise LVEF values were respectively:64.9i12.8% and 64.7±15.5% while hyperthyroid and 62.6:1:11.1% and 71.0i10.2% while euthyroid. Thus, a raise in LVEF during e~eroisehas been observedin eu~yroid patients. We conclude that: 1) Hyperthyroidism affects cardiac contractility, which is e0qoressedby lack of the physiological increase of the LVEF during exercise. 2) This disfunotisn seems to be reversible,i.e. exercise LVEF values return nom,,el after effective treatment of hyperthyroidism.

*:p'~0.03; *:p<0.02; ":p,~0.005; $:p<0.005; ':p':0.001 It was 600 kcounts/fiame. Thus, for a better homogeneity o f H3, a good compromise is 16 frames/cycle and 600 kcounts/frame.

52.4

53.1

EFFECT OF CALCIUM CHANNEL BLOCKER (VERAPAMIL; ISOPTIN SR) ON DIASTOLIC DYSFUNCTION. Bisson G., LeBlanc M., Dufort L., Lepage S. Facult6 de M&lecine, Universit6 de Sherbrooke, Sherbrooke, Canada.

STRESS FDG PET IMAGING AS A NEW APPROACH TO THE DIAGNOSIS OF CAD IN WOMEN B. L. Abramson, T.D. Ruddy, R. deKemp, L. Laramee, B.Aubrey, M. Aung, R.S. Beanlands. The University of Ottawa Heart Institute, Ottawa, Canada. The diagnosis of CAD in women is a major challenge. FDG(F-18 deoxyglucose) PET is the gold standard for detection of myocardial ischemia at rest. There has been little published on stress FDG imaging. We performed stress FDG PET testing in 19 women (age=59+/-10, ht=l.6m+/-0.1, wt=77kg+/-14) referred for evaluation of chest pain. 17 patients (pts) had had prior stress T1-201 images which were positive (pos) or equivocal for attenuation artifact. FDG mad SestaMIBI were injected at peak stress (treadmill n=8, dipyridamole n=l 1), followed by PET and SPECT image acquisition. Myocardial regions of reduced MIBI uptake were identified. Increased FDG uptake in such regions defined ischemia. Angiography was performed on all pts. 9 of the 19 pts had significant CAD (stenosis>_50%). 8 of 9 pts with CAD had FDG ischemia (sens.=89%). One of the 10 pts without CAD had FDG ischemia (spec.=90%). Overall diagnostic accuracy was 89% (17/19). 9 pts without CAD had had pos. or equivocal T1-201 images(false pos. rate 53%(9/17)) but no FDG ischemia. Stress FDG PET shows excellent sensitivity, specificity, and predictive accuracy. This novel approach may complement the diagnosis of CAD in women.

*:p<0.02; ':p<0.00t

The optimal number of frames/cycle was: 16 frames/cycle. Then, ECG-gated studies were reconstructed with different counts/frame for 16 frames/cycle a btitnal counts/frame was defined. kcounts/frame 200 400 600 800 ds phase 264-8" $ 214-5"$ 204-55 20=1:4" delta 95% 504-28*0 ' 32+15" 294-10' 26+8 ° delta 5% -294.13 -304.16 -264.12 -274-12

A M A P R I L 8

Evaluation of diastolic function is important since an isolated dysfunction can be responsible for cardiac insufficiency. Our goal was to evaluate the effect of Verapamil in patients with " pure " diastolic dysfunction. 8 patients with hypertension (off all medications except diuretics), clinical dyspnea (without significant alteration of the FEVj), no significant CAD and diastolic dysfunction were randomized. Each one had 3 radionuclide ventriculographies : baseline (B), placebo (P) and one after 7+/- 3 days of Verapamil (V). Results expressed as the mean +/- st dev were: Baseline Heart Rate 71,4+/-9,6 Ejection fraction 55,1+/-8,0 Peak Filling Rate* 2,02+/-0,24 1/3 Filling Fraction 0,32+/-0,08

Placebo

Verapamil

70,4+/-10,0 57,8+/-8,0 2,18+/-0,67 0,33+/-0,13

70,0+/-12,0 59,9+/-10,4 2,44+/-0,55 0,45+/-0,14

Comparison between B vs P and B vs V for these parameters using Pearson's correlation showed a significant improvement (p double sided) for PFR (p<0,02) and 113 FF (p<0,05) with the use of Verapamil. There was no significant difference for the other parameters. Condusion: our results show that Verapamil (Isopfin SR) can modulate parameters of diastolic function measured by radionuclide ventriculography in patients with relatively " pure " diastolic dysfunction. * EDV/sec

Journal of Nuclear Cardiology Volume 4, Number l, Part 2

Abstracts Tuesday morning, April 8, 1997

53.2

53.4

UPTAKE RATE KONSTANT (Ki) OF F-18 FTHA-PET

Progressive recovery of tissue perfusion following coronary artery bypass grafting; Evidence of microvascular stunning. Nicos Spyron, Franco Sogliani, Rodney Foale, Wyn D. Davies Rex de L. Stanbridge, Paolo G. Camici. MRC Clinical Sciences Centre, RPMS, Hammersmith Hospital and St Mary's Hospital, London, UK.

AS I N D I C A T O R O F M Y O C A R D I A L VIABILITY IN R E G I O N S W I T H R E D U C E D PER,FUSION G. Sehulz, J. yore Dald, L. Banneitz, H.L Kaiser, U. Cremerins, 0. Sabri, U. Buell. Aachen University of Technology, Germany

$63

To investigate the diagnostic value of 14(R,S)-[F-lg]-fluoro-6-thiahepta-decanoid acid (FTHA) as specific marker of the B-oxidation we studied 16 patients with angiographically proven advanced coronary heart disease. AI1 patients underwent PET with 150 MBq 2-[f18]-fluoro-2-deoxyglucose (FDG) and 250 MBq FTHA (dynamic acquisition up to 60 mitt past injection) preceded by SPECT with 400 MBq [Tc-99m]-2-methoxy-isobutyl-isonitril (MIBI) for peffusion assessment. All three methods were quantitatively evaluated in 33 polar left ventricular regions per patient. Regiolml uptake of MIBI, FDG and FrHA was normalized to the region with highest MIBI uptake (100%). We derived uptake rate konstant (KJ) of FrHA by Patlak plot analysis, plasma corrected for uninetabolized free FTHA. Out of the 166 regions with severely reduced perfusion (MIBI <50°/) we extracted three groups by FDG uptake: hibernating (FDG _>70%), intermediate (FDG 50-69°,/0) and scar myocardium (FDG <50%). In regions identified as hibernating by FDG PET, static FIHA uptake (68+_39%) was significantly higher than in intermediate (39+91%) or scar (39+19%). Ki also discriminated hibernating (0.045,Al.031ml/g/min) 'from intermediate (0.033-:-0.021ml/g/min) and scar (0.03 li-0.015ml/g/min). We conclude that preserved viability in patients with regional perfusion defects (hibernating myocardium) may traced by FTHA. However, neither static FTHA uptake nor dynamic measurement (Ki) discriminated the intermediate state from scar.

We have previously demonstrated a delayed recovery of coronary vasodilator reserve (CVR) up to 3 months following successful an~oplasty suggesting abnormal microcirculatory function. To extoad this observation, we studied 7 patients who hadcoronary artery bypass ~afting (CABG) in whom the left internal mammary and gastroepiploic arteries and saphenous vein grafts were used Ibr complete coronary revascularizztion. Regional myocardial blood flow (MBF, ml/min!g), at baseline and following iv dipyridamole infusion (dip, 0.56 mg/kg over 4 minutes), was measured with O-15 labelled water and positron emission tomo~aphy at baseline (bas) and 1 and 6 months after CABG. Bas-MBF was corrected (c) for the rate pressure product (RPP) using the following formula: cMBF-bas = MBF-bas x 10EI/RPP. CVR was calculated as MBF-dip/cMBF-bas. Whole heart cMBF-bas was comparable before and 1 and 6 months after CAISG (1.39+-.29, 1.21_4-.33 and t.15_+.26, respectively). Whole heart dipMBF was 1.36_+.28 before CABG, 1.98_+.5 one month after (p=ns) and 2.38_+.75 at 6 months (p<.05 vs pre-CABG): Whole heart CVR was 1.00+_.24 before CABG, 1.73+_.57 one month after (p<.01) and 2.29_+.36 at 6 monflas (p<.0005 vs pre CABG and p<.05 vs 1 month). In conclusion, our study shows that following CABG there is a pro~essive recover7 of CVR over a six month period. This might reflect morphoflmctional changes in the microcirculation due to chronic ischemic heart disease which recover slowly after CABG alrd form the substrate of "microvascular stulming".

53.3

53.5

ACUTE ANTIISCEMIC EFFECT OF ANGIOTENSIN CONVERTING ENZYME INHIBITION IN PATIENTS WITH CORONARY ARTERY DISEASE C.A. Schneider,E. Voth, D. Moka, F.M. Baer, E.Erdmann, H. Schicha, U. Seehtem. Klinik III ~ r Innere Medizin, University of Cologne, German),.

PET MYOCARDIAL PERFUSION IMAGING REDUCES THE COST OF CORONARY DISEASE MANAGEMENT M. Merhige, G. Stern, D. Saiki, T. H o u s t o n , V.Shelton, S U N Y at Buffalo. U.S.A.

Although angiotensin converting enzyme (ACE) inhibition may improve myocardial blood flow to ischemic regions, this effct has never been directly demonstrated in humans. Twelve normotensive patients with high-grade single vessel coronary artery disease, normal left ventricular function and a pathological stress test underwent [~50] water positron emission tomography at rest and during maximal dobutamine stress (mean dosis: 35p.g/kg/min). This imaging sequence was repeated after ACE-inkibition with 10 mg Quinaprilate i.v. The rate pressure product at rest was significantly lower after ACE-inhibition (9200+1850 vs. 8830+1540 nunHg/nda, p<0.01), but similar during stress (16050+3160 vs. 16780+3450 mmHg/min, n.s.)

W e hypothesized that myocardial perfusion imaging (MPI) with P E T and Rb-82 results in c o s t savings in coronary disease (CAD) management, c o m p a r e d with

Myocardial Blood Flow ml/min/g

Control regions Ischemic regions rest stress rest stress Before Quinaprilate 0.9_+0.3 2.3_4-1.4" 1.2_+0.5 1.2_+0.6 AflerQuinaprilate 1. l_-L-0.4 3.0+_2.0* 1.1_+0.5 1.9+1.2"+ *p<0.01 vs. rest; +p<0.01 vs. stress before Quinaprilate 10 mg of Quinapritate i.v. significantly improves myocardial blood flow to acutely ischemic myocardium.

SPECT MPI, due to improved test accuracy, despite its increased cost. We compared costs and outcomes in 303 sequential CAD patients evaluated with PET MPI, and 102 patients imaged with SPECT, matched for pretest likelihood of disease. There were no deaths in the PET group. One myocardial infarction occurred just prior to angiography, which was recommended due to a high risk PET result. Angiography, CABG and PTCI rates (%) for SPECT vs. PET were: 32.3 vs 9.8; 7.8 vs 3.3; and 2.0 vs 1.7 n SPECT PET

102 303

Pretest Probability 0.36 _+0.14 0.37 +0.17

DiagnCost/Pt $2,617 $2,380

TreatCost/Pt $3,333 $1,724

Total Cost/Pt $5,950 $4,104

Concl: PET-MPI results in: reduced invasive procedures, excellent outcomes and a 30% cost-savings compared to conventional management.

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Abstracts Tuesday morning, April 8, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

53.6

53.8

ERGOTAMINELIMITS t~'PEREMIC ~,~'OCARDL~LBLOOD FLOW IN HUMANS Tomaso Guecchi-Ruscone, Roberto Lorenzoni, Flemming Hermansen, Nigel Legg, Dilnitris Tousoulis, *Gillian Shepherd and Paolo G Camici. MRC Clinical Sciences Centre, Royal Postgraduate Medical School, Hzmmersmith Hospital, London; *GLAXO-WellcomeLtd, Greenford,UK

MYOCARDIAL UPTAKE OF TC-99M-NOET DURING ADENOSINE HYPEREMIA IN DOGS WITH MILD TO MODERATE CORONARY STENOSES DK Glover, M Ruiz, G Vanzetto, DA Calnon, DD Watson, GA Beller. University of Virginia, Charlottesville, USA.

Although ergotamine (E) is beneficialfor miNaine it may cause myocardialiscbemia. Aim of this study was to ascertainwhether E affects myocardialblood flow (MBF) in humans. A double blind randomized,placebo(P) controlled, crossover study was performed in 15 rnigraineurs(age 54-+4,4 males) with no history of isehemic heart disease, normal echocardiogramand negative stress test at high workload. MBF (ml/g/m) was measured with positron emission tomography and ~SOlabelled water at baseline (bas) and after intravenous dip~ridamole(dip; 0.56 mg/Kg). Bas and dip MBF weremeasuredtwice, i.e. after intravenousE (0.25 rag) or P, on two differentdays. Bas hemodyuamicand MBF data ',afterP aaxt E werenot significandydifferent.By contrast, E led to significant changes in dip-lvtBF, coronary vasodilator rcsen.'e (CVR, dipMBF/bas-MBF)and minimal coronaryresistance (min-CR, mcan dip-pressure/dip-MBF,mmHgiml/mlg). bas-MBF dip-MBF CVR min-CR P 1.45+_0.31 3.72+_1.05 2.71_+1.15 27_+8 E 1.44_+0.41 2.62+_1.11" 1.81_+0.50" 42__.15' Data are shown as mean _*SD. (* = p<0.01, P vs E). Conclusions: E significantly reduces near maximal coronary vasodilationin human subjects without history of ischcmic heart disease, probably through activation of corouary serotonergic and]or c~l-adrenel~creceptors. This could explain the ischemic effect of E in the heart.

We have previously demonstrated that the myocardial uptake of TI-201 (T1) more accurately tracks coronary flow during adenosine (Ado) hyperemia than either Tc99m-sestamibi or tetrofosmin. NOET is a new Tc-99mlabeled myocardial perfusion tracer which redistributes similar to T1. We examined NOET uptake in 9 dogs with either critical (n=4) or mild (n=5) LAD stenoses after simultaneous injection with microspheres during Ado infusion (300 gg/kg/min). The mean Ado flow and tracer activity ratios (LAD/LCX) by well counting were: Group Flow NOET critical 0.14+.02 0.34+.03* (* p<0.01) mild 0.53+.09 0.71+.07" Thus, NOET appears to be the first Tc-labeled perfusion tracer with myocardial uptake and retention similar to that previously observed with TI in this same model. Combined with its redistribution property, these data suggest that NOET may be well suited for pharmacologic stress imaging.

A M A P R I L 8

53.7

53.9

D I S T R I B U T I O N O F Tc-99m BMS-194796 IN NOR~IAL AND ISCHEMIC MYOCARD1UM C O M P A R E D W I T H TISSUE F L O W AND O X Y G E N G Johnson III, KN Nguyen, Z Liu, P Gao, *AD Nunn and RD Okada, William K. Warren Medical Research Institute of the Univ. of Oklahoma Health Sciences CenterlTulsa, OK.

A NOVEL ANTIMYOSIN IMMUNOLIPOSOME TREATMENT FOR PRESERVATION OF DYING MYOCYTES: TRITIATED THYMIDINE UPTAKE STUDIES

The purpose of this study was to determine Tc99m-BMS194796 (Te-796) activity in normal and ischemic myocardial sites compared with arterial flow (AF) by flowmeter, tissue flow (TF) by microspheres and tissue oxygen (TO) by phosphorimeter. After baseline, AF was reduced to 9.14-1.2% (mean+sere) in the LAD of 5 dogs. Microspheres were injected and TO measured. Tc-796 (1110 MBq) was injected during 90% stenosis. The myocardium was assayed in a gamma well counter. Normalized TF was 18.544.5% (p<0.03 from AF=9.1+1.2%). Normalized TO was 6.64.1.7% (p<0.05 from TF=18.54.4.5%). Hypoxic to normoxic Tc-796 activity ratios were 2.6:k0.4. The Pearson correlation coefficient for well-counted myocardial Tc-796 activity and TO was -0.88, p<0.0002. In conclusion, normalized tissue flow is greater than normalized tissue oxygen during severe stenosis in this model. Tc-796 demonstrates increased retention in myocardial regions made hypoxic due to low flow ischemia and is inversely correlated with tissue oxygen.

B.A. Khaw, I. Vural, V.P. Torchilin, and J. Narula. Northeastern University and Massachusetts General Hospital, Boston, USA

The hallmark of cardiomyocyte death is the loss of sarcolemmal integrity. We reasoned that if an antibody specific for intracellular antigen such as myosin is exploited to carry a lipid plug to the site of sarcolemmal breach, it should seal the membrane lesion and preserve the cell viability. We subjected 2x106 H9C2 eardiocytes in culture to hypoxia for 1-5 days and used liposomes coated with antimyosin antibody as lipid plugs (AML). Cell viability was assessed by 3H-Thymidine (3HT) uptake. Untreated hypoxic cardiocytes (HC), cardiocytes treated with plain liposomes (PL), and H9C2 cells cultured in normoxic conditions (NC) were used as controls. After 24h, 3HT uptake by NC cells (3.7×106 cpm) was similar to AML (3.3x106 cpm). Viability of PL (1.1×106 cpm) or HC (~0%) at 24h was significantly lower. Viability of AML-treated cells at 2,3,4 and 5 days was 1.3×106, 0.7x106, 0.2x106 and 0.1x10 s cpm, respectively, compared to 0.06x106, 0.01 ×10 s, 0.002×106 and 0.007x10 s cpm of PL treated cells. Since 3HT uptake of IL-treated hypoxic cells increased by 250% of the starting 2×106 H9C2 cells and similar to NC cells at 24h, AML treatment must allow the cardiocytes to continue replication even under severe hypoxia. This study shows the potential use of AML for long-term preservation of myocardial viability.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Tuesday afternoon, April 8, 1997

53.10

62.2

QUANTITATION OF MYOCARDIAL INJURY FOLLOWING BRAIN DEATH: A Tc-99m PYROPHOSPHATE STUDY. C R Satur, W Martin, D J Wheatley Department of Cardiac Surgery, Royal Infirmary, Glasgow, Scotland. Donor hearts for transplantation should ideally be free from occlusive coronary artery disease and receive minimal myocardial injury from the time of brain death to transplantation, This injury is in part due to the pathophysiological processes accompanying brain death. The aim of this study was to investigate whether uptake of pyrophosphate in the myocardium occurs following brain death and whether this uptake can be used as an index of degree of damage. Twenty one male pigs were anaesthetised and ventilated prior to the induction of brain death in 15 animals and in 6 sham experiments. The animals were monitored for 6 hours, and 1 hour prior to termination of the experiment 540 MBq of Tc99m was injected intravenously, and a 10% reference standard retained. Subsequently, the heart was imaged on a gamma camera and uptake of pymphosphate estimated. The % uptake in brain death animals ranged from 0.202-2.14%(median 0.406) whilst in shams the values were 0.022-0.298%(median 0.193), p<0.01. This study clearly demonstrates myocardial uptake of pymphosphate following brain death, with significant individual variation. This is a potential method of assessing degree of myocardial damage in donor hearts prior to implantation.

Prognosis Following SPECT Perfusion Seintigraphy Demonstrating Isolated RCA Distribution Ischemia.

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T. Bateman, J. O'Keefe, Jr., C. Barnhart, J. Case, M. Williams. Mid America Heart Institute, Kansas City, MO. We previously showed that nonextensive ischemia (5.1 of LAD or multivessel ischemia or abnormal TI-201 lung uptake) on SPECT scintigraphy predicts an excellent long-term outcome with medical treatment. There remains concern that risk is related to the extent and/or severity of ischemia even in a single territory. To address this for the RCA territory, we retrospectively identified all 793 patients in our database with reversible or palntially reversible peffusion defects involving inferior, inferoseptal, and/or inferolateral walls and no other abnonnalities. 775 pts (18 lost) were followed for 21 +- 15 months. Demographics: mean age 64 yrs, known CAD 635, prior MI 363, and angina 408. Using a 20segment model, mean no. of abn. segments at stress and at rest were 12 and 5. Sttrmned stress and rest scores were 6.3 and 3.0. There were 13 cardiac events (1.7%): 5 nonfatal MI and 8 deaths. The event rate was 1.3% for medical and 3.6% for revascularized pts (13=0.09) Revascularized pts had more angina, more prior MI, and less lmown CAD, but similar perfusiou defects. Size/severity/extent of reversibility of peffusion defects only weakly correlated with events. Conclusion: Single-vessel RCA distribution ischemia predicts a benign outlook for at least 2 years. The event rate is lower in pts treated medically. Neither extent nor severity of the perfusion defect strongly correlates with subsequent death or myocardial infarction,

T U E S D A Y P IV

T u e s d a y P M , April 8, 1 9 9 7 Sessions 62-67 62.1 IMPACT OF THE SUBSEQUENT CHANGES IN ANTI-ANGINAL THERAPY ON THE PROGNOSTIC VALUE OF EXERCISE T1201SPECT PARAMETERS F. Branly, P.Y. Marie, P. Olivier, N. David, N. Quid, T. Arsena, N. Hassan, M. Angioi', N. Danchin, G. Karcher, A. Bertrand. Department of Nuclear Medicine, Nancy, France. Exercise T1201-SPECT provides important prognostic information in patients with coronary artery disease (CAD). However, anti-anginal treatments, which are likely to modify the results, are frequently withdrawn before or further adapted after the test. This study was aimed to determine whether exercise TI201-SPECT gave better prognostic information when performed under the same anti-anginal treatment than that given for follow-up. We studied 421 patients, with known or suspected CAD, who had exercise TI201-SPECT and coronary angiography and who were subsequently treated medically. Anti-anginal treatment at exercise TI201-SPECT was the same as that given for follow-up in 168 pts (GI) and different in 256 (GII). During 5+2 yrs of follow-up, 45 pts (11%) had cardiac death or myocardial infarction (GI : 12% vs GII : 10%, NS). On a Cox model, prognostic informations provided by each catheterization variable (number of diseased vessels, LV ejection fraction, ..) and by extent of irreversible Tl201 defect, were highly significant in both GI and GII ; those variables provided equivalent relative risks in the 2 groups. By contrast, both presence and extent of reversible TI201 defect gave a highly significant prognostic information in GI (p =.007 and p =.001) but not in GII (p =.9 and p =.08). In patients with known or suspected CAD; exercise ischemia, assessed by TI201-SPECT (reversible defect), has a lower prognostic significance when the test is not performed under the same anliauginal treatment than that given for follow-up.

62.3 STRESS SPECT THALLIUM PREDICTORS OF OUTCOME IN ISCHEMIC HEART DISEASE. N. Nallamothu, W. VanDecker, E.R. Acio, J. Heo, A.E. Iskandrian, Allegheny University of the Health Sciences, Philadelphia, PA, USA. This study examined the stress SPECT thallium predictors of cardiac death and non-fatal myocardial infarction in 997 patients (pts) with ischemic heart disease who also had coronary angiography. During a mean follow-up of 30+10 months, th6re were 117 events. Univariate Cox survival analysis identified the size of the perfusion defect, increased lung thallium uptake and left ventricular (LV) dilation as independent predictors of events. By multivariate analysis, LV dilation, but not increased lung thallimn uptake, provided incremental prognostic value (P<0.05) to perfusion defect size which was the strongest predictor (x2=25, P<0.0001). The polar maps (>15% vs <15%) method and segmental score >3 vs <3) provided comparable results in separating low from high risk groups. The annual event-free survival was 2% ha the low risk group and 7% in the high risk group (P<0.05). The site of the defect (anteroseptal vs inferolateral vs both) was not a useful prognostic marker (event rates 16% vs 18% vs 18% respectively). Thus, the extent of jeopardized myocardium but not the site is the most important predictor of outcome. The presence of LV dilation provides incremental prognostic value.

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Abstracts Tuesday afternoon, April 8, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

62.4

63.1

INTEGRATING CLINICAL HISTORY AND STRESS PERFUSION VARIABLES INTO A SCORING SYSTEM Leslee J. Shaw, Rory Hachamovitch, Daniel S. Berman, Salvador Borges-Neto, Thomas H. Marwick, Michael S. Lauer, Mark I. Travin, Gary V. Heller, D. Douglas Miller, Duke University, Durham, NC

CONCLUSION. From this multicenter study, guidelines of care may be designed that integrate key clinical and nuclear variables into a highly predictive tool.

IDENTIFICATION OF MYOCARDIAL HIBERNATION: COMPARISON OF TI-201, Tc-99m TETROFOSMIN SPECT AND CINE MAGNETIC RESONANCE IMAGING M Gunning, C Anagnostopoulos, CJ Knight, J Pepper, K Fox, DJ Pennell, PJ Ell, SR Underwood.Royal Brompton Hospital and UCLMS, London, UK Both radionuclide uptake and contractile response to ionotropes have been used to identify hibernating myocardium. We compared TI-201 and 9~mTc-tetrofosmin SPECT, and dobutamine MRI in this context. We studied 23 patients with 3 vessel CAD and impaired LV function. Prior to CABG, rest and dobutamine stress(5-10ug/kglmin) cine MRI, stress/redistribution and rest/redistribution TI201 SPECT and stress/rest 9~mTc-tetrofosminSPECT were performed. Resting cine MRI, was conducted after CABG. Images were visually scored for tracer uptake and contractile function using a 9 segment model of the LV. Results 82 of 145 asynergic segments improved function. Sensitivity Specificity Pos. Predictive RedistributionTI-201 68% 49% 64% Late-RestTI-201 76% 44% 64% Rest 99mTc-tetrofosmin 66% 51% 64% Dobutaminecine MRI 50% 81% 77% Rest/redistributionTI-201 18% 83% 44% Conclusion Late-rest TI-201 tracer uptake was the most sensitive technique for identifying hibernation, but less specific than rest/redistribution and dobutamine MRI.

62.5

63.2

WHAT IS THE PREVALENCE AND PROGNOSTIC SIGNIFICANCE OF ISCHEMIA DETECTED BY TL20I SPECT IMAGING PROXIMAL TO BYPASS GRAFT INSERTION IN PATIENTS WHO HAVE UNDERGONE CORONARY ARTERY BYPASS GRAFTING (CABG)?

IS EXERCISE TI201-SPECT WITH REST-REINJECTION ABLE TO PREDICT THE LEFT VENTRICULAR REMODELLING OCCURRING AFTER ANGIOPLASTY OF AN INFARCT RELATED ARTERY ? M. Angioi, N. David, P.Y. Marie, N. Quiri, N. Hassan, T. Arsena, N. Danchin, G. Karcher, Y. Juillitre, A. Bertrand. Department. of Nuclear Medicine, Nancy, France.

To examine the integrative relationship between clinical risk and nuclear imaging results, we enrolled 9,791 stable angina patients from 7 hospitals. A Cox proportional hazards model was used to predict time to cardiac death (overall rate 2.2% at 2.5+1.5 years). For clinical history, diabetes =16, hyper.- tension=8, congestive heart failure= 43, and prior myocardial hffarction=8. For age, points for 50 years=50, 60=67, 70=83, 80=100. By the number of perfusion areas, with ischemia, points are 1=27, 2=34, 3=56; with infarction, 1=22, 2+=49. Based upon the multivariable model, sum the points to estimate 2-year survival= Points 67 90 114 170 195 211 233 234243 252 274 / Survival 0.995 .99 .98 .9 .8 .7 .6 .5 .4 .3 .1

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T. D. Miller, B. P. Mullan, D. O. Hodge, T. F. Christian, R. J. Gibbons, Mayo Clinic, Rochester, MN, USA. An anecdotal observation from SPECT T1-201 imaging in patients after CABG is redistribution localized to the basal cardiac segments that represents ischemia proximal to graft insertion. To determine the prevalence and prognostic significance of this finding, 413 patients (age 62+9 years, 332 M, 81F) who performed an exercise T1201 test within 2 years after CABG were followed for a median duration of 5.4 years. The prevalence of localized basal ischemia was: overall 12%, left anterior descending coronary distribution 4%, fight coronary distribution 6%, and circumflex coronary distribution 3%. There were 18 cardiac deaths and 33 nonfatal myocardial infarctions during follow-up. Although the number of ischemic T1201 segments was associated with outcome (univariate %2=7.6, p=0.006), localized basal ischemia was not (22=0.3, p=NS). CONCLUSION: Ischemia proximal to bypass graft insertion is present in only 12% of patients with prior CABG and is not predictive of future cardiac events.

Angioplasty (PTCA) of an infarct related artery may improve left ventricular (LV) remodelling. Whether this improvement is related to residual viability, as assessed by the TI201 rest-reinjection technique, remains to be determined. We prospectively assessed the evolutions of LV end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF), in patients who underwent a PTCA of an infarct related artery. All had pre-PTCA exercise TI201-SPECT with rest-reinjection and underwent, before PTCA and _>4 months later, quantitative LV and coronary angiograms. LV volumes and EF were calculated with the area-length method. Sixty four patients were studied (56.+.10 years, 53 men). Among these, 61% had had thrombolytic therapy, 84% had Q wave MI and 92% had one vessel disease. In the overall population, there was no significant _>4-month improvement in either EDV (81+21 vs 84+_23 ml/m2), ESV (40-2-15vs 402_18 ml/m2) or EF (51+10 vs 54+12 %). Ou a stepwise regression analysis, extent of underperfused areas with > 50% of Tl201-uptake at reinjection was the best independant predictor of the evolutions of EDV (p=.007), ESV (p=.0005) and El:: (p=.007) ; and presence of a restenosis was an additional predictor for the evolutions of ESV and EF (both p=.02). Extent of viable and ischemic myocardium, as assessed by the TI201 rest-reinjection technique, is a predictor of not only the evolution of LV systolic function (EF, ESV), but also of the remodelling process (EDV), occurring after angioplasty of an infarct related artery.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Tuesday afternoon, April 8, 1997

63.3

63.5

CONTRAST ECHOCARDIOGRAPHY VERSUS PERFUSION SCINTIGRAPHY FOR ASSESSMENT OF VIABILITY IN CHRONIC CORONARY DISEASE

DETECTING MYOCARDIAL VIABILITY IN INFARCTED AREA, - COMPARISON AMONG EXERCISE REINJECTION TL SPECT, REST MIBI SPECT AF'fER NITRATE ADMINISTRATION AND REST TL SPECT AFFER TLGLUCOSE-INSULIN INFUSION.T. Toyama, H. Hoshizaki, N.lsobe, T. Tomita, S.Sakurai, H.Adachi, S. Naitoh, A. Nogami, S. Ohshima, K. Yuasa, K.Taniguchi, T. Suzuki and R. Nagai. Gunma Prefectural Cardiovascular Center, Maebashi, Japan.

Sarah Vernon, Michael Ragosta, Larry Gimple, Eric Powers, George A. Beller, Sanjiv Kaul. University of Virginia, Charlottesville, VA, USA The aim of this study was to compare myocardial contrast echocardiography (MCE) to myocardial perfusion scintigraphy (MPS) for the assessment of viability in patients with chronic coronary artery disease (CAD). Accordingly, perfusion scores using the two techniques were compared in 91 ventricular segments in 21 patients with prior (>6 week old) myocardial infarction. Complete concordance between the two techniques was found in 63 regions (69%); 25 regions (27%) were discordant by only 1 grade and complete discordance (2 grades) was found in only 3 regions (3%). A kappa statistic of 0.65 indicated good concordance between the two techniques. The correlation between MCE and wall motion score was closer than between MPS and wall motion score (rho=-0.63 versus rho=-0.50, p=0.05). It is concluded that MCE, using intracoronary injection of microbubbles, provides similar information regarding myocardial viability as myocardial perfusion scintigraphy (using venous injection of tracers) in patients with chronic CAD and prior infarction. MCE may, therefore, have clinical application in the cardiac catheterization laboratory.

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Detecling myocardial viability in hffarcted area, we compared exercise reinjection TI SPECT (RE-T1) with rest MIBI SPECT after nitrate administration (ISDN 5rag iv) (NI-MIBI) and rest T1 SPECT after TI -glucose-insulin (111MBq TI in 10% glucose 250ml plus insulin (5U) and 10mEq KCI ) infusion (GI-TI) in 24 infarcted areas of 16 patients, whose all coronary lesions were over 99% stenosis. SPECT image was divided into 20 segments and regional tracer uptake was scored by using 4-point scoring system (0=normal~3=defect), and summed up to defect score (RDS) of each infarcted lesion. Of 17 infarcted areas with fill-in on RE-T1, tracer uptake was more improved in 11 areas (65%) on NI-MIB1, and 16 areas (94%) on GI-TL Of 7 infarcted areas without fill-in on RE-TI, tracer uptake was more improved in 2 areas (29%) on both other images. RDS of three methods were 9.2-t-5.3 on RE-T1, 7.9"t-5.8" on NI-MIBI and 6.9"t5.6*# on GI-T1 ( *;p<0.01 vs RE-T1, #;p<0,05 vs NI-MIBI ). Detecting myocardial viability, NI-MIBI and GI-TI were more useful than RE-TI. Furthermore, GI-TI may estimate myocardial viability more clearly than NI-MIBI.

63.4

64.1

ACIPIMOX IS EFFECTIVE TO PROMOTE THE UPTAKE OF GLUCOSE IN MYOCARDIAL SPECT WITH 18-FDG R.Valkema, D.Poldermans, A.E.M Reijs, R.Rambaldi,. T.Rietveld, J.W.O. van den Berg, J.Bax, P.M.Fioretti,. E.P.Krenning. University Hospital, Rotterdam, The Netherlands.

1S ALTERED CENq'RAL PROCESSING OF AFFERENVI" SIGNALS THE CAUSE OF CHEST PAIN IN SYNDROME X? SD Rosen, E Paulesu, RSJ Frackowiak and PG Camici. MRC Clinical Sciences CentrelRPMS, Itammersalith Hospital, London UK

Acipimox, a nicotinic acid derivative, inhibits peripheral lipolysis. It is a potential alternative to hyperinsulinemic euglycemic clamping for promoting glucose (Glu) uptake in myocardial studies with F-18 fluorodeoxyglucose (18-FDG). We studied 21 patients (pts) with chronic coronary artery disease by dual-isotope single photon emission computed tomography (SPECT) using 600 MBq Tc-99m-tetrofosmin and 185 MBq 18-FDG, after 2 x 250 mg acipimox p.o. and a light tow-fat carbohydrate-rich meal. Serum Glu and free fatty acids (FFA) were measured at baseline and 2 hr after acipimox, just before injection of 18-FDG. On the short-axis SPECT slices we determined myocardial to blood pool ratios (M/B) in normally peffused areas with small circular regions of interest. In 16 pts without diabetes mellitus (DM) mean FFA dropped by 77% from 418 to 82 nmol/I, while mean Glu rose within normal limits, from 4.8 to 6.6 mmol/I. The mean M/B was 4.2 [range 2.2 - 7.5], corresponding with good image quality. In 5 pts with DM mean FFA dropped similarly from 488 to 137 nmoltl. In 2 pts Glu remained stable or decreased after 8 U of insulin s.c., in 1 pt Glu decreased spontaneously; M/B ratios ranged from 2.8 to 3.1, with good image quality. In 2 pts GIu increased, with M/B ratios of 1.3 and 0.9, and poor image quality. We conclude from these preliminary data that serum FFA drop sharply after acipimox, with good cardiac 18-FDG uptake in pts without and with DM, if hyperglycemia is controlled. This is a potentially practical approach for cardiac studies with 18-FDG.

The aefiology of syndrome X (SX, an~nal pain mad isehaemic-likc stress ECG despite a normal coronary arteriogram) remains to be elucidated. The myocardial ischaemia hypothesis of chest pain in SX has been undermined, whereas abnormalities of pain perception have beenshown. Wehave nsedpositron emission tomography with H~tS(Y to measure regional cerebral blood flow (rCBF)~hanges as an index off neuronal activation: a)during chest pain in SX patients and b) duringl angina pectoris in coronary ,'u'teD' disease (CAD) patients. Nine SX (71 female, age 56±11, meav_e_SD)and 9 CAD (7 male, age 614-7 3,ears)' were studied. With stress, normal ventricular function was, demonstrated in the SX patients despite'ischaemic-like ECG, but there~ were reversible wall motion abnormalities in the CAD patients, Intravenous dobulammc (D) was used to induce the chest pain. rCBF was measnred during: 1) rest; 2) placebo; 3) rest; 4) low dose D; high dose D (provoking chest pain); and 6) rest. Chest pain ocurred in response to low dose D in 4f9 SX but in no CAD patients (p=NS). During scan 5 (high dose D) chest pain was reporledin all cases, being scored comparably by both groups (6.3--.1.8 in CAD vs 7.6-*2.0 in SX; p=NS). During scan 5, ischaemic-like ECG changes were noted in 9/9 CAD and 8/9 SX. Mmximal D dose was equivalent for both groups. During chest pain, SX patienls showed significantly greater increases in rCBF in the nfidbrain, right thalamus and right insular cortex and bilaterally in the frontal and prefrontal cortices. The brain areas activated are similar in both SX and CAD, suggesting that in SX the afferent pain signals do originate from the heart. However the degreeand extent of activation is disproportionately greater in SX and occurs in the absence of correlates of myocardi~d ischaemia such ~ ventficular walt motion abnomaaliJes.

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T U E S D A Y

Abstracts Tuesday afternoon, April 8, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

64.2

64.4

EFFECT OF NTG, COLD PRESSOR TEST AND DIPYR1DAMOLE ON CARDIAC PERFUSION IN NORMALS. M.Bottcher, M.Madsen, T.Toftegaard, J.Czernin. Dept. of Card., Aarhus Univ. Hosp., Denmark and UCLA Med. Sch.,Los Angeles, CA

CORONARY FLOW RESERVE IS REDUCED IN YOUNG ADULT INSULIN DEPENDENT DIABETIC PATIENTS J. Knuuti, O.-P. Pitk~nen, P.Nuutila, O.T.Raitakari, H.Laine, T.Takala, H.lida, J.Viikari, T.RSnnemaa. Turku PF:T Center, Finland.

Myocardial perfusion (MP) scanning is used for detection of CAD. Several techniques have been used to increase resting MP and improve count statistics. Among these are nitroglycerin (NTG) and cold pressor stimulation (CPS). It is not clear, however, whether any of the two techniques affects MP. We studied 24 volunteers (25+_5 years) veith love"likelihood o f CAD. Using dyaaamie PET we measured MP and coronary vascular resistance (CVR). Values were obtained on 2 separate days: Day 1: a) Rest, b) atter 90 see. of CPS and c) 2 rain. after oral NTG, (ISMO ~ one puff sublingually). Day 2: a) Rest, b) during dipyridamole (0.56 mg/kg/min, over 4 min.) to obtain maximal ] L. *)p<0.05 vs. rest. N=24 Rest CPT NTG DIP MP 0.85_+0.15 0.88M}.23 0.89_+0.22 2.42_+0.73 * RPP 7309+1514 873252552* 8177+2695 10936+_.2443* CVR 91+14 113_+28' 89+23 374-13 * MP in ml/g/min, RPP in mmHg x min -~, CVR in (ml/g/nma)/mmHg. Conclusion: CPS or NTG administered before perfusion scanning does not enhance MP. The mechanism o f action is most likely an auto-regulator), mechanisms counteracting the epicardial vasodilatation (NTG) and the increased perfusion pressure (CPS), at the level o f the resistance vessels. DIP primarily acts on myocardial resistance vessels and thereby prevent counter regulating mechanisms.

We have previously shown that coronary flow reserve is decreased in young asymptomatJcsubjects with hypercholesterolemia. The prevalence and incidence of coronary heart disease (CHD) are increased in IDDM. To investigate whether coronary vascular reactivity is impaired in young IDDM patients without diabetic complications and whether this is independent to other known risk factors, myocardial blood flow and flow reserve were measured using positron emission tomography and '~Olabelled water. We studied 12 nonsmoking male IDDM subjects (age 30.1+6.6 y) and 12 healthy matched volunteers (CTRL). Subjects were similar with respect to blood pressure and serum lipid concentrations (Total, LDL- and HDL-cholesterol, trigycerides, Apo A-l, Apo B and Lp(a)) (ns. IDDM vs. CTRL). IDDM subjects were without microvascular complications and had normal exercise echocardiography. Myocardial blood flow was measured during euglycemic hyperinsulinemia (insulin infusion lmU/kg/min) at baseline and after dipyridamole infusion. The baselinemyocardial blood flow was similar in both groups (0.88+0.25 vs. 0.84+0.16 mL-g'.min ~, CTRL vs. IDDM, ns.). The flow during hyperemia was lower in IDDM (3.2+1.6 vs. 4.5+1.4 mL-g4-min4, p=0.04). Consequently, coronary flow reserve (the ratio of flow during hyperemia and at baseline) was lower in IDDM than in CTRL (3.76_+1.69 vs. 5.31+1.86, p=0.04) and the total coronary resistance during hyperemia was higher in IDDM (53.7+31.5 vs. 31.4+11.6 mmHg.min-g-mL 4 p=0.03). In conclusion, coronary vascular reactivity is impaired in IDDM without mierovascular complications. This abnormality can not be explained by other known risk factors for CHD. The results imply early impairment of coronary vasomotion in IDDM patients which may represent an early precursor of future CHD.

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64.5

Evidence of diffuse myocardial B-adrenoceptor downregulation after myocardial infarction in the absence of cardiac failure. Nicos Spyrou. Stuart Rosen, Rodncy Foale, Wyu D Davies and Paoto O Camici, MRC Clinical Sciences Centre; RPMS, Hammersmith Itospital andSt. Mary's Hospital, London (-L;'K).

EFFECT OF REPERFUSION FOLLOWING MYOCARDIAL INFARCTION ON MEASUREMENT OF MYOCARDIAL PERFUSlON WITH RB42 AND PET IMAGING TD Ruddy, RA deKemp, MM Dalipaj, MT Aung, JS Vincent, RS Beanlands, Ottawa Heart Institute, Ottawa, Canada

Following acute myocardial infarction (AMI) fllere is evidence of sustained sympathetic overacfivity. Whether this leads to abnormalities of myocardial l~-adrcnoceptor (tAR) density is not known. This density canbe detetminednon invasively using positron emission tomo~aphy (PEF). The aim of this stud',' was to assess whether there are significant changes in myocardial I.~AR density in the subacute phase of infarction. Wc studied 25 patients (mean a ~ 52± 11 years)who had no previous ischaemia, diabetes, hypertension or renal disease andhadsingle vessel disease. Results in patients were comparcdwith those obtained in 18 age matched controls (mean a ~ 48±14 3'ears, p=NS vs patients). All patients were in NYIIA class I, they were studied between 1 and 2 months post AMI. Regional myocardial BAR was measured by PET using HCGP 12177 as the ligand. R e s u l t s There was a significant difference in whole heart I~AR density in patients compared to controls (5.784-0.90 vs 8.35+2.00 pmol/g, p<0.001). In the patients, I~AR density' was similar in the infarcted aald the remote non-infarcted rc~ons (5.70+1.30 vs 5.79-+1.00 pmol/g, p=NS) supplied by angiograpthcally normal or non si~maificantly diseased corona_O, aiteries. Conclusions: 1- In the subacute phase of infarction there is a sig-aificant dowuregulatioa of myocardial BARs suggesting sustained sympathetic overactivity. 2- The reduction of BAR deimity affects both infarcted and remote non-infarcted myocardium to a similar extent. This suggests a diffuse myocardial autonomic dysftmction which might play a role in leli ventricular remodelling.

Microvascular damage with reperfusion results in progressive reduction of Rb-82 retention in the presence of a patent infarct-related artery. The resulting perfusion defect cannot be differentiated from one due to coronary artery occlusion. Quantitation of myocardial perfusion (RMP) following reperfusion would overcome this problem. This may be possible with dynamic PET imaging using a 2 compartment kinetic model that separates kl (uptake) from k2 (washout). Dogs underwent LAD occlusion for 90' with (n=3) and without (n=5) reperfusion for 60'. Measurements were made at rest and during dobutamine infusion to increase RMP. Polar map sectors were generated automatically and corresponded to radiolabeted microsphere pieces of ~ 1 gm each. Regions containing many sectors were selected from the center of the infarct and non-infarct areas. PET data correlated lineady with RMP determined with microspheres: reperfusion RMP = 0.3 + 1.2"kt, (r=0.91, n= 95 regions, p<0.001); persistent occlusion RMP = -0.03 + 1.0*k~, (r=0.91, n= 120 regions, p<0.O01); all dogs RMP = 0.08 + 1.2"k~, (r=.88, n= 215 regions, p<0.001). RMP can be accurately measured with Rb-82 modeling using the uptake rate k~ in a canine model of myocardial infarction with and without reperfusion and has potential for clinical application to evaluate the success of reperfusion.

Journal of Nuclear Cardiology Volume 4, Number I, Part 2

Abstracts Tuesday afternoon, April 8, 1997

65.1

65.3

GENDER DIFFERENCES IN ACUTE CHEST PAIN MYOCARDIAL IMAGING MG Levine, FJ Wackers, RS Morris, AW Ahlberg, CC McGill, A Russell, MP White, D Waters, GV Heller Hartford Hospital, University of CT, Hartford, CT, USA

NATURAL HISTORY OF CHANGES IN MINIMAL CORONARY VASCULAR RESISTENCE IN CARDIAC ALLOGRAFT RECIPIENTS

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J. Narula, S.S. Kushwaha, G. Zervos, M.J. Semigran, A.J. Fischman, N.A. AIpert, G.W. Dec, H. Gewirtz. Massachusetts General Hospital, Boston, MA, USA

Limited data are available correlating acnte chest pain (ACP) imaging with predischarge stress imaging. Therefore, 127 patients (pts.) were injected with Tc-99m tetrofosmin within 5 hours of CP. All pts. underwent subsequent exercise (90) or pharmacologic (37) stress testing with Tc-99m sestamibi myocardial SPECT imaging. All images were read independently without knowledge of the pt. identity or type of test. Patients (+)Acute Imagint (-) Acute Imaging n # correlate/total# # correlate/total# ~_11Pts. 127 25/36 (69%) 82/91 (90%) Male Pts. 74 20/25 (80%) 45/49 (92%) Female Pts. 53 5/il (45%)* 37/42 (88%) *p<0.05 Conclusions: Although negative ACP imaging is highly concordant with subsequent nuclear stress imaging in men and women, positive ACP imaging in women is less concordant with subsequent nuclear stress imaging.

We tested the hypothesis in humans that minimum coronary vascular resistence (CVR) increases as a function of time after heart transplantation (HTx). PET measurements of myocardial blood flow (MBF) were made at rest and with adenosine in 24 patients (19M, 5F; 53+10 yrs) after 1-86 mo of HTx. None had allograft rejection at the time of PET and all had demonstrated normal coronary angiograms during their closest annual exam. There was no difference in prevalence of hypertension, hyperlipidemia or immunosuppressive regimen.

65.2

65.4

CORONARY MICROCIRCULATION DISORDERS IN IDIOPATHIC VENTRICULAR FIBRILLATION.

ISOSORBIDE MONONITRATE 0MDUR) PRODUCt~ gJSTAINED REDUCTION OF REVERNBLE DEFFL-T EXTENT IN PATIENTS WITHOUT EXERCISE ANGINA: ASSENMENT BY QUANTITATIVE EXERCI~ Tc-99m 5ESTAMIBI/RENFI"1-201MYOCARDIALPERFUSIONSPFL-T. Howa~ C. Lewin, Roty ~ c h , M i d ~ H a ~ Ckxty Wigams,Juli Sdrrfidt, Jd'~ F ~ artiDarfiet S Bmm~ CedasNn~MedicalCenter. Los Ang~, CA,USA

JG Meeder, PBF Mensink, HJGM Crijns, ES Tan, PK Blanksma, J Pruim, EE van der Wall, W Vaalburg, KI Lie. University Hospital Groningen, The Netherlands. Using parametric 13N-ammonia PET, myocardial perfusion reserve, resistance and heterogeneity between 9 patients who survived idiopathic ventricular fibrillation and 9 matched healthy controls were compared. In patients all conventional cardiac investigations, including spasm provocation, were normal. Perfusion at rest and during dipyridamole stress testing (DST), and perfusion resistance at rest did not differ between patients and controls. However, patients showed a lower stress test/rest ratio, (2.08+0.69 vs. 2.70+0.41; p<0.05) and a higher perfusion resistance during DST (0.38+0.11 vs. 0.28+0.06 mmHg*min*100glml; p<0.05). Both at rest and during DST, coefficients of variation of perfusion in 480 separate segments, as a measure of perfusion heterogeneity, were comparable between patients and controls. Since the reduced vasodilator reserve is found together with angiographically normal epicardial coronary arteries, it may be speculated that coronary microcirculation disorders play a pathophysiological role. The absence of perfusion heterogeneity suggests that focal ischemia does not act as an arrhythmogenic factor in idiopathic ventricular fibrillation.

Interval After HTx number of patients MBFrest (mllmin/g) MBFadenosine CVRrest CVRadenosine

1-12 mo

13-36 mo 37-86 mo Control

9 1.9+1.0" 3.4_+1.0 89_+50* 36_+10

8 1.2+0.7 3.4_+0.7 136_+60 36_+12

7 1.0+0.3 2.5_+1.3" 142_+50 60_+34*

10 1.0_+0.2 3.2+0.5 120_+24 37+_9

MBFrest was elevated and CVRrest reduced in the first year; both values subsequently returned to baseline. MBFadenosine (microvascular dilator capacity) remained normal up to 3 yrs. CVR increased over time and correlated significantly with the interval after HTx (rest, r= 0.5; p= 0.01; adenosine, r= 0.7; p= 0.0006). PET measurements of MBF are helpful in following onset of graft vasculopathy at microvascular level. These timedependent changes likely represent immune-mediated injury.

We prospectively evahaed the knpact of IMDUR on myocardial peffusionushgqu~itativdy assessedSPECT.We studied 20 pts web a history of stableangina(rrmn a~ 72 yrs) I:eforeU~atu~t, fryedays (EARLY) and 30 to 35 days (LATE) atter fim-apy ~ IMDUR 120mg/dusingdual isotope myocardialp~fitsion ~EC-T (DIMPS). Eightofthe~ pts hat 6therm ~ w i t h ermSsetest~ (EYF) c~had l~,olutbnofEIT ~ arl~Nter the~y withlMDUR. All EFT werep~forrmd to a least 85% MPHK DIMPSwm assessedushg validaed q u ~ i v e ~lysis sott~e (CEqtd®). Defect ~ w~ ~bally and w-thin ~ coror~ry ~ t~r~ory (CVI). ~atisical analysis wes p~forn~ ushg one way repe~ed mms~es ANOVA. Gbbal quantitative pfffusion defect e~tff~t w~s ~uced du~g treatrr~ with IMDUR both ha pts with and witlx)ut EI~ k~ed~r~a(19% vs. 20%,p<0.02). Wghingot9 diffetmceswere preser~txlweentx~tir~ ard EARLY,as webas, I:melheand LATE h both goups (con'ectedp<0.05). To e~r~qe taSayphyla~, A % ha defect ~ r ~ fr~n basdine to EARLYwas oomparedto Ixv,eline to LATEfor~c~l md eata CVT,p=NS forall. Condusions:Tremr~ ofpts with~ with IMDUR deaemes khm'~iae~ter~evenintl~ air,race of EIT hduced regina. Tlx~ is no eviJmce of tadayphyaxis, h either grotrp, at up to 35 days.

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Abstracts Tuesday afternoon, April 8, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

66.2

65.5 CORONARY VENTRICULAR

RESERVE AND DYSFUNCTION

LEFT IN

HYPERTROPHIC C A R D I O M Y O P A T H Y R. Lorenzoni, R. Gistri, F. Cecchi, G. Chiriatti, W.J. McKenna and P.G, Camici. Hammersmith Hospital, London, U K

T U E

S D A Y

We evaluated the role of the impairment of the coronary vasodilator reserve (CVR) on left ventricular ( i V ) function in 84 patients (pts; 62 M, age 42_+12 years) with hypertrophic cardiomyopathy (HCM). LV end-diastolic (LVEDD) and end-systolic diameters (LVESD) were measured by 2D-echo (mm), and fractional shortening (FS, %) was computed as (LVEDD-LVESD)/LVEDD x 100. Baseline (bas) and dipyridamole (dip; 0._56 m ~ K g ) myocardial blood flow (MBF; ml/min/g) were measured with PET and N l 3 - a m m o n i a or O15-water. CVR was computed as dipMBF/basMBF. Pts in advanced NYHA classes had lower dipMBF and CVR (ANOVA, p<0.05). NYHA I NYHA II NYHA I I I (n=53) (n=24) (n=7) bas MBF 0.83±0.27 0.91±0.37 0.70+_0.22 dip MBF 1.57_+0.64 1.52_+0.58 0.96_+0.32 CVR 1.93e0.64 1.69+0..54 1.40+_0.43 A negative correlation was found between dipMBF and LVESD(R=0.23; p<0.05). The 12 pts with abnormal FS had lower dipMBF (1..54±0.65 vs 1.86_+0.60; p
LONG TERM PROGNOSTIC VALUE OF NORMAL MYOCARDIAL PERFUSION SClNTIGRAPHY IN PATIENTS WITH ABNORMAL REPOLARIZATION AT REST. R.G.E.J. Groutars, C.A.P.L Ascoop, J.F. Verzijlbergen, J.C. Kelder. St Antonius Hospital, Nieuwegein, The Netherlands. The prognostic value of bicycle exercise testing in presence of abnormal repolarization at rest is poor. We evaluated 296 patients with chestpain, nonspecific ECG abnormalities at rest and normal planar myocardial perfusion scintigraphy with a mean follow-up of 6 years. In that period 8 patients died (2.7%), 12 had myocardial infarction and 27 underwent. PTCA or CABG. The event rate for myocardial infarction or death was 0.56%/year and for PTCA or CABG 1.51%/year. Hazard ratio for any cardiac event was for female gender 0.43 (p=0.03), diabetes mellitus 4.64 (p=0.017) and typical angina pectoris 3.39 (p=0.002). If maximal heart frequency remained under 85% of predicted value, combined with additional ST segment depression of at least 2 mm, the hazard ratio was 4.44 (p=0.001). If the exercise test was terminated because of angina pectoris the hazard ratio was 2.80 (p=0.001). Basic (age and gender), clinical and exercise variables were assessed using reciever operator characteristics (ROC) curve analysing. This revealed that prediction of any event was better by combined basic and clinical variables than combined basic and exercise variables (ROC area = 0.73 ± 0.06 versus 0.68 i 0.05; p<0.05). We conclude that, despite abnormal repolarization at rest, patients with normal myocardial perfusion scintigram have excellent prognosis.

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66.3

SPECT-TL HAS AN INCREMENTAL pREDICTIVE VALUE OVER CONVENTIONALEST AFTER 6 YEARSOF FOLLOWUP. G. Vanzetto, O. Ormezzano, J. Maehecourt, D. Fagret, B. Denis. UniversityHospital, Grenoble,France.

G R E A T E R I S C H E M I C BURDEN IN PAINFUL THAN SILENT PATIENTS WITH POSITIVE EXERCISE TEST. C.Mareassa, M.Galli,C.Baroffio,R.Campini, P.Giannuzzi. S. Maugefi Foundation IRCCS, Veruno, Italy.

The aim of this studywas to examine the long term prognostic vahie of T1-SPECT in a large series of patients. The same cohortof 1174 patients (75% men / 25% woman) with low or intermediatecardiac risk already evaluated previonsly 33 months following an exercise-stress redistribution TI-SPECT was followed for an average period of 72-+18 months and Keplen-meyer survival analysis was performed. EST xvas defined as positivev,gan a ST depression ~ 1 mm after J paint oceured (n--267, 23%), negativewhen no ST depression oeeured and -> 85% of predicted heart rate (PHR) was achieved(n=620, 53%), and submnximal whon < 85% of PHIl was achieved (n---287, 24%). T1-SPECT was considered as abnormal(n=749, 66%) if there was one or more segment with fixed or reversibledefect Results : At follow up, 88 pts died (46 from cardiovascular deaths and 42 from other causes) and 50 pts experienced a non fatal M/. After an abnormal T1-SPECT the major cardiovascular events rate (MCE) (cardiovasculardeaths and MI) were significantlyhigher (OR = 3.6, p<0.0l). Accordingto results ofEST, TISPECT had a high negativepredictivevalue for occurrenceof MCE even when EST was positive or submaximal (0.98 when EST was positive, 0.97 when EST was negative and 0.94 when EST was subma'ximal. Cenversly, the rate of MCE ~as significantlyhigher in patients with a large defect (more than 3 segments with a permanent defect) than in patients with a small defect (23% versus 10%, p<0.0l). Conclusion : The excellent predictive value of T1-SPECT for occurrenceof/vICE is eenfhqned over 6 years of follow up. Fttrthermore, it has an additive predictivevalueover conventionalEST.

The relation between the presence of painful or silent STsegment depression _>lmm (ST$) and the amount of jeopa rdized m y o c a r d i u m was evaluated in 215 consecutive pts (58+-9 yrs; 83% male) with ischemic heart disease (previous MI, documented C A D or >80% pretest CAD probability and associated reversible hypoperfusion) undergoing rest and exercise sestamibi SPECT on separate days; all showed ST$ during exercise. The extent of hypoperfusion was quantified from the polar maps of tracer distribution as % of L V surface with tracer uptake <2.5SD from our mean normal value. ST$ was painful in 94 pts (45%, Gr.1) and silent in the remaining 121 (55%, Gr.2). There were no differences between the 2 groups regarding age, history of hypertension, diabetes, previous MI and multivessel CAD. Gr.1 achieved a lower work-load (4.7+1.8 vs 5.9+ 1.5 METS; p<0.001) and exercise time (9.9-+4.8 vs 12.8+ 3.3 rain; p<0.001) than Gr.2. Moreover, ST$ occurred in Gr.1 at a lower rate-pressure product (p<0.05) and earlier (7.2_+4.2 vs 8.9-+3.0 rain in Gr.2; p<0.01). The extent of exercise hypoperfusion was also greater in Gr.1 (19-+15% vs 13+13% in Gr.2 pts; p<0.05) as well as the extent of reversible (exercise - rest) hypoperfusion (12+12% vs 7_+7% in Gr.2; p<0.001). I n conclusion, our results suggest that in pts with ischemic heart disease, painful ST$ during exercise is related to a greater ischemic burden.

Journal of Nuclear Cardiology Volume 4, Number I, Part 2

Abstracts Tuesday afternoon, April 8, 1997

66.4

66.6

Incremental Value Of Simultaneous Assessment Of Myocardial Function And Perfusion For Detection Of Coronary Artery Disease. Onhayoun, E.; Coca, F.; Basti6, D.; Payoux P.; Esquerr6, LP. Service Central de M6decine Nucl6aire. H6pital Purpan. Toulouse. France. Objectives : Testing the incremental value of function analysis when added to SPECT for the detection Of coronary artery disease (CAD), especially in multivessel disease. Methods : 100 patients with angiographically proven CAD, (33 single vessel (SV) and 67 multivessel (MV) disease), underwent MIBI SPECT with simultaneous assessment of ventricular function (LVF) by first pass radionuclide angiography at rest and during stress. Abnormal LVF consist in wall motion abnormalities during stress or Peak Ejection Fraction (PEF) < 0.55 or decrease of EF > 0.05. Results : Comparing SV and MV, global CAD detection rate was 69.7 vs. 80,6 % for stress test, 69.7 vs. 86.7% for LVF, 75.8 vs. 92.5% for SPECT and 75.8 vs. 97 % for SPECT+ LVF. In 3 cases, perfusion was strictly normal, and function showed RWM abnormality with decrease of the ejection fraction at stress, allowing detection of 2 bi and one triple vessel disease. MV CAD detection rate was 49.3 by SPECT vs. 55.2% by SPECT + LVF. SPECT and LVF were concordant to show only one territory abnormality in 41.8% of MV pts and no abnormality in 3 %. PEF was significatively lower in MV group than SV group (0.57 vs. 0.51%, p < 0.05). Conclusion : Addition of .LVF to SPECT : 1) improves overall detection of CAD. 2) provides a better assessment of MV disease by improving detection of MV abnormalities over SPECT in some patients and confirming that SPECT does not underestimate ischemia in others.

ANTI-ISCHEMIC DRUGS REDUCE SIZE OF REVERSIBLE DEFECTS IN DIPYRIDAMOLE/ SUBMAXIMAL EXERCISE TI-201 SPECT IMAGING T. Sharir, S. Livschitz, B. Rabinowitz, P. Chouraqui. Sheba Medical Center, and Tel Aviv University, Israel.

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Beta-blockers (BB), nitrates (N) and calcium channel blockers (CCB) are not usually discontinued prior to dipyddamole/submaximal exercise TI-210 SPECT (DSPECT) imaging. To evaluate the effect of these drugs on the extent of perfusion defects, D-SPECT was performed with (SPECT 1) and without (SPECT 2) antiischemic treatment in 21 patients (pts). SPECT images were obtained at stress and 4 hrs later. Nineteen pts received CCB, 17-N, and 5-BB. Baseline systolic BP was smaller in SPECT 2 than in 1 (129_+18 mm Hg vs 140+_23, p<0.03). Baseline heart rate (HR), HR and systolic BP at peak exercise, were similar in SPECT 1 and 2. The results (mean 4- SD) of the quantitative analysis of stress defect size from )s are: Territory(%) LAD LCX RCA Total SPECT 1 26+_23 57+37 33+_25 33_+13 SPECT 2 17_+14 49_+39 21+19 24+_13 p 0.009 0.01 0.002 0.002 Rest defect size was similar in both studies. We conclude that anti-ischemic drugs decrease size of reversible defects in pts undergoing D-SPECT.

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SURVIVAL, FUNCTIONAL AND SYMPTOMATIC OUTCOME IN PATIENTS WITH CONGESTIVE HEART FAILURE UNDERGOING CABG. F Haas, C. Haehnel, S. Martinoff, H. Meisner. German Heart Center Munich° Germany Despite poor prognosis of patients (pts) with advanced coronary artery, disease .(CAD) and congestive heart failure (CI-IF) receifi'ng medical treatment, CABG remains controversial due to presumed high operative risk and lack of functional and sy.mjatomatic imprgvements. 131 pts (mean a~e 63.3 yrs) "&itlaalett ventncular ejection traction (EF) < 3"5% (mean: 29.1), who underwent lsotated CABG were analyzed during a 5:year period. In 25.2% of the pts, the.EF was < 25%. Preoperatively, 56.5% ofpts had CI-IF without, angina pectoris and 75.6% of the pts were assigned toNYt-rA classes III and IV. The mean number of gr.arts was 3.8/patient, the internal mammary artery was usei:l in 72.5%. l'n-hospltal mortality was 5.3~%. N/ 1, 3 and 5 years the survival was 91%, 83% and 49%. Lett ventricular EF, assessed by_ radionuclide ventriculography_ increased from 22.0 to 31.2% (p=0.007) in the group witl~ EF _< 25% (45% increas.e) and from 30.6 to 36.1% .(p=0.007) in the group with EF > 25~o to 35%. (19% increase). The percentage improvement between the two groups was sighincanuy ditterent (p=0.04). NYHA class improved postoperatively by 1.6 categor!es and CCS class by, 2.3 ca're, ones. The results show that patients witla a~tvanced CAD and CI-IF benefit from CABG. Patients with ejection fractions _< 25% showed most marked improvement. The results support the demand of a more aggressive surgical approacli towards C A B U instead of meilical therapy or the decision tot cardiac transplantation in this particul~ir patient group.

66.7 ROLE OF MIBI SPECT IN THE RISK STRATIFICATION OF CAD PATIENTS: MULTIVARIATE ANALYSIS FOR HARD (HE) AND SOFT EVENTS (SE). P.Zanco, A.Zampiero, A,Favero, F.Chierichetti, N.Borsato, B.Saitta and G.Ferlin. Nuclear Medicine-Castelfranco V.-Italy. To evaluate the role of MIBI scan as a prognostic tool in CAD, 300 consecutive pts submitted to rest-stress MtBI SPECT were enrolled. Up to now 269 pts (206m, 63f, aged 27-68 yrs) have completed a follow up of at least 4 yrs(range 48-72 mo, mean 55). At enrollment 92 patients were affected by a previous myocardial infarction (MI), Occurring at least 3 mo before, and 72 pts suffered from typical angina. Beside SPECT findings, age, gender, risk factors for CAD, previous MI, angina, stress double product and heart rate, as well ST depression during stress were included in the analysis. During the follow up, 46 pts(17%)presented cardiac events:5 cardiac death and 8 MI(HE), and 33 unstable angina(SE). Considering HE and SE together, multivariate analysis, using Cox proportional hazard model, indicated that an abnormal MIBI scan(p=0.0008,relative dsk-RR=30.3)and the presence of typical angina(p=0.0008, RR=2.7)were the only significant and independent prognostic factors. Considering HE, the extension of the defects on stress SPECT appears significant (p=0.002, RR=10.7), while reversibility of the MIBI defects (p=0.002, RR=27.1) appeared the most significant prognostic factor for SE. In conclusion, our experience reveals a fundamental role for MtBI scan in longterm risk stratification of CAD and suggests different SPECT markers for HE and SE.

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Abstracts Tuesday afternoon, April 8, 1997

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66.10

EFFICACY OF FDG SPECT AND DOBUTAMINE STRESS E C H O C A R D I O G R A P H Y TO PREDICT IMPROVEMENT OF REGIONAL LV FUNCTION.

PREDICTION OF FUNCTIONAL RECOVERY AFTER REVASCULARIZATION USING I- 123 LABELLED BETA-METHYL-BRANCHED FATTY ACID (BMIPP) AND THALLIUM MYOCARDIAL SCINTIGRAPHY. J. Taki, K. Nakajima, I Matsunari, K. Ichiyanagi, A Muramori, E. Hwang, H. Bunko, S, Takata, N. Tonami. Kanazawa University School of Medicine, Kanazawa, Japan.

Jeroen J Bax, Jan H Cornel*, Frans C Visser**, Paolo M Fioretti#, Arthur van Lingen**, Cees A Visser**. Leiden, *AIkmaar, **Amsterdam and #Rotterdam, The Netherlands.

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Journal of Nuclear Cardiology January/February 1997, Part 2

FDG SPECT and dobutamine stress echocardiography (DSE) can be used to predict improvement of regional contractile function after revascularization. This study aimed to Compare both techniques in their prediction of recovery of function after revascularization. Thirty patients underwent FDG SPECT (during hyperinsulinemic glucose clamp), resting T1-201 SPECT (to assess resting perfusion) and 13SE. Regions with normal perfusion/FDG uptake or FDG-perfusion mismatch were defined as viable. On DSE, viability was defined as improved wall thickening during low-dose dobutamine infusion. Improvement of function was assessed by echo betbre and 3 months after revascularization. All techniques (echo and nuclear) were analyzed in a 13-segment model. Sensitivities (SE) and specificities (SP) of both techniques were assessed in all segments, in hypokinetic (H) and in akinetic (A) segments. The results are as follows: all H A DSE (SE/SP) 89%/82% 94%/45%# 81%/97% FDG (SE/SP) 84%/86% 81%/91% 86%/74% #P<0.05 (SP DSE vs SP FDG) The sensitivities of FDG SPECT and DSE to predict improvement of regional LV function were comparable. When wall motion severity at baseline was considered both techniques were equally sensitive/specific. In the hypokinetic segment however, DSE had a lower specificity, indicating overestimation of recovery by DSE.

Iodine-123 labeled BM1PP has been used as a myocardial fatty acid probe. To evaluate the ability of BMIPP to predict functional recovery in patients with chronic coronary artery disease (CAD), 26 patients with CAD (23 men and 3 female, aged 59_+9.4) underwent resting BMIPP and 2°~TI SPECT (stress-reinjection 2°~TIin 24 and resting Z°~Tl in 2 patients). Cardiac function was evaluated by gated blood pool scinfigraphy before and 2-5 weeks after percutaneous transluminal angioplasty (n=lg) or bypass surgery (n=7). Myocardial area was divided into 18 segments in each patients and segmental radiophannaceutical uptake was analyzed semiquanfitatively (normal:defect score=0 to absent uptake: defect score=4). The area of discordant uptake of BMIPP less than reinjection 2°~T1 before revascularization was a predictor of EF improvement after revascularization (r--0.58, p<0.01); however, the area of reversible ~°~T1defect was not (r=0.34, p=ns). In conclusion, discordant BMIPP uptake less than reinjection ~°~TIis a potential predictor of functional recovery in patients with CAD.

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67.1

POST-REVASCULARIZATION RECOVERY OF FATTY ACID METABOLISM IN HIBERNATING MYOCARDIUM UNDER TREATMENT OF POTASSIUM CHANNEL OPENER. Y.Kuwabara, K.Fujii, K Matsuno, T.Himi, KFusejima, T. Saito, Y.Masuda. Third Department of Internal Medicine, Chiba University, Chiba, Japan

99mTC-MlI3I Gated SPEC'I? i~ Clinical b2vaiuaUon of Isehemic Heart Disease: a Comparison with Stress-Rest M I B I SPECT Giacontuzzi F, Guerrll I]~, Slavich GA, Fresco C, F~ore~i PM. Istituto di ?,.2"dicina),:uc!eare. ~,';titutodi Cardio!ogia. :~icnda ()spedaliera :TMN'[I'dine~ itaiia.

Previous studies reported that fatty acid metabolic disorder in hibernating myocardium sustained even after reperfusion. This study was designed to evaluate if use of K+ channel opener (nicorandil) improved fatty acid metabolism after elective PTCA. Method:Thirty seven patients undergoing elective PTCA were randomly assigned to receive nicorandil (group N, n=l 8) ,and control (n=19). Group N received nicorandil intracoronaly at PTCA, and orally for 3 months after PTCA. Both groups underwent BMIPP SPECT imaging before PTCA, soon after PTCA (72hours), and 3 months later. Result: In control, mean BMIPP uptake score decreased from 1.8 to 1.5 soon after PTCA. In group-N, mean BMIPP uptake score increased from 2.1 to 2.3. BMIPP uptake score recovery was significantly greater in group-N than that in control, and this persisted for three months (2.5 vs 2.1, p<0.05). Cundusion: These results suggested that nicorandil prevented fatty acid metabolic disorder during ischemic event at PTCA, and accerelated the metabolic recovery after angioplasty.

Back~rmmd:, Stress-rest NI2B[ SPECT ~.,eo..,.,~,).eqtsir.es two separate in iecfions and acquiskions, wh.ilc G~ed X~[f}31 SPECT (G) with a single ir~.jectio,'.~and acquisition allows the evahsation of str.:.-.~perNsion (diastolic image) and wall ~odo," and thickening at rest. Patiems and methods: 204 consecutive patients with suspected ~scheamic heart disease without arrhytha~ias suh,nitted to SR unden,vent also G: A aemiquart.tJtativescr:.re ¢0 normal to 3 no perfusion) was "~sedto assess perlLsioa of the ]eft w,ntriele (divided i~ 1~ segments)..<-~aagiogap}'~ic data were avafiabie for 66 patients rj~ this st~bgro~,.p ~he ptzwz~ler,~ceof disease was 96~0, Results: Sensitivity and specificity were 95"~0 and 75% ~'r stress rest and 98% and 75~ Dfi~r':3aged The ~otste pert\,lsion score was 76] with gated and !2,25 fo.r ~;tzess-rest (3.60 per patient with gated versus 3.()6 per patient with swes:~ rest) Conclusions: In our £eries G allowed hotter i:~age quality without Iosmg specifi.city or sensitivity. 8esides tilat, ~.: has the advantage or reduci~g costs, acquisition tm~e m~.d exposure of both patients an.d opera~vrs

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Tuesday afternoon, April 8, 1997

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67.4

GATED SPECT THALLIUM EJECTION FRACTION CALCULATION COMPARATIVE TO CALCULATED ECHO EJECTION FRACTION. W. VanDecker, A. Khan, J. Krackow, J. Nocalla, A. Sokil. Allegheny University Hospital - East Falls Campus, Phila., PA

SIMUL'rANEOI'S EVALUATIONOF MYOCARDIALPERFUSION AND VENTRICULAR FUNCTION USING ONE DAY SEPARATE ACQUISITION TIIALLIUM-201/STRESS TETROFOSMIN DUAL ISOTOPE GATED SPECT. INITL~kL EXPERIENCE IN MEXICO AND LATIN-AMERICA.E.Alexanderson.A.Puente,,A.Arroyo,D.Bialostozky D.Victofia. InstituteNacionalde Cardiologia"IgnacioChavez".MexicoCity,MEXICO. Gated SPECT is a useful technique to evaluate myocardial perfusion, walt motion abnormalities and wall thickening_ There is not published experience in l,atin-America using dual isotope rest TI-2011 stress tctrotbsmin dual isotope gated SPECT.METHOD: We studied 27 pallents with coronary artery disease. CoronaD' angiography was pcrt't~nned in all the patients. We used a 3 mCi rest TI-201 SPECT followed by stress and 15 mCi tetrofesmin (fated SPECT acquisition. To validate myocardial perfusion and wall motion findings patients relunling next 3 to 5 days lbr stress sestamibi injection and Gated SPECT acqt,isition. Perfusion data were read by 2 blinded experts using 20 SFECI" scgmem analysis and each segment was scored using 5 points scoring system (0=normal, 4=absent uptake). To study wall motion we divided the heart iu 29 segments and eyeD' segment was scored using a 4 points scale (3=normal, 2=mild h~pokinesia, l=severe hypokinesia, (l=akinesia). RESULTS: The perlitsion segmental score agreement between stress tetrolbsmin and stress sestmnibi and the wall motion segmental score agreement between tetrofosmin and sestamibi were:

The left ventricular ejection fraction (LVEF) is an import> -~ prognostic and therapeutic marker. A recent report (Germar,v, (7. et.al.: J. Nuc Med 1995:36:2138) using an automated meth~: showed excellent correlation between gated SPECT sestamibi LVEF and radionuclide angiography. Although the count statistics are lower with thallium than technetium, same program may generate accurate LVEF's from gated SPECT thallium. We compared 11 LVEF's on patients with a SPECT thallium study and an echocardiogram. The echo LVEF's were generated by an automated endocardial detection algorhythm and calculated using a modified two chamber approach. The echo LVEF was 41 -+ 18% and the gated thallium LVEF was 49-+25% (r=0.87).

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Conclusion: 1. Preliminarily, LVEF by gated SPECT thallium appears feasible. 2, There is good correlation between echo and nuclear LVEF by these techniques.

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CONCLUSIONS:Rest T1-201/ Stress tetrofosmin dual isotope Gated SI~I'("F technique is a good protocol to asess simultaneously myocardial perfusion and wall motion. It showed a good agreement wifll rest T1201/stress sestamibi dual isotope Gated SPECT study.

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: Quantitative Myocardial Kinetic Energy: A new physiological information hidden in the gated perfusion ironing. Villas B6as CM; Gutierrez MA; Vieira CHB; Salts FV; Scares

AUTOMATED QUANTITATIVE ANALYSIS OF SESTAMIB! STRESS GATED SPECT TO DETECT N O R M A L M Y O C A R D I A L SEGJ~VIENTS

J Jr; Izaki M; Giorgi MCP; Meneghetti JC. Heart Institute-Sio Pauio University-Brazil We developed a quantitative analysis of myocardial kinetic energy from gated '~9=Tc-MIBI perfusiun SPECT ironing. This new method quantifies 3D left ventricular motion by means of the optical flow technique extended to the voxel space. The wall motion is represented by a series of 3D velocity vector fields that are computed for each voxel on the sequence of cardiac volumes. From the velocity vector it is possible to obtain an estimation of the kinetic energy (Ke) for each voxel (Ke=l/2m[v~x+VZy+V~z]). Regional motility and LVEF are very good predictors of myocardial rese~'e and vlability.ln spite of this, we know that in severe muscle disfunction these parameters are less discriminative and susceptiSIe to error analysis. Differently from these conventional methods the Ke showed minimal variation inter and intra obser~'ers. Ke ~ndex (Kem~ -Ke.,t~ /Ke .....) in 8 normal volunteers (aging 24-34 yrs) was 96,75 _+ 0,89 and in 15 pts. with LV disfunction (26-25 yrs;FC III or IV of NYHA) was 56,3 +_ 9,6. Seven of those pts. with basa! index of 54,20 + 11,48 when stressed with 10 ug/Kg/min showed Ke index of 60,14 1 +_3,60. The authors conclude that the myocardial kinetic energy quantification may provide global and regional ventricular motion assessment independent on size and orientation of the heart. This kind of parameter can be iml)ortant in critical clinical decisions and management of pts. with severe myoeardiopathy and important in the evaluation of the myocardial reserve or viability on severe cardiac disfunction.

V. Todino, G. Rubini, G. Valentini, A. Ferraironi, A.Giordano, A. Cuocolo. "Regina Apostolorum" H.- Albano L. (Rome), Italy The Aim o f our study is to evaluate the improvement o f diagnostic capabilities o f stress Gated SPECT data to reco~tise normal myocardial segments. An automatic and operator indipendent sofware has been developped from Bull's eye maps to obtain a 16 segments model to quantify myocardial perfusion (MP) and diastole to systole counts increase (CI) in 20 patients. Stress and rest MP was expressed as percent o f maximal stress activity myocardial segment (MS), and we considered hypoperfused the segments with stress perfusion <70%. We used a threshold o f >-- 10% for reversibility (REV). A stress diastole to systole CI > 50% was the threshold for define normal MS. 171/320 MS were nonnoperfused with a CI o f 88 ± 31%. 41/149 MS were hypoperfused showing a REV>_ 10%, and 108/149 MS have a REV < 10%. 28/108 showed a CI < 50% (true hypoperfused MS). The 80 retm}ants MS showed >_ 50% CI and were loealizzed 46 in inferior wall and 25 in the apex. This operator indipendent method permits to recognize hypoperfused segments without reversibility as normal myocardial seganents. It solves the problem o f hypoperfusion & l e f t inferior wall due to attenuation and lower thickening or greater motion o f apex.

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Abstracts Tuesday afternoon, April 8, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

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67.8

GATED IMAGING DURING BOTH REST & STRESS TC 99M SESTAMIBI IMAGING WITH A NOVEL GATING PROGRAM FOR "FULL VIEW" LEFT VENTRICULAR FUNCTION Haresh Majmundar, Steven Grant, Nancy Prill, Calvin Hou, Elliot Wagner, Thmnas Watters, Gregory. Thomas. Mission lnternal/t:[edical Group, ~ission Viejo C4. USA The increased availability of inexpensive computer memory has ~Jlowed the development of software to acquire and then simultaneously display 10 gated SPECT images of each of the 3 standard axes (Lear. Univ of Colorado). This program was used in 207 patients (pts) undergoing stress Te99mSestamibi imaging at an outpatient center. Left ventricular (LV) ejection fraction (EF) was calculated using an area based method. Imaging was initiated 30 min post exercise stress and 60 min post pharmacologic stress. To our knowledge, the comparison of both rest and post stress gated SPECT imaging in the same pts Ires not been reported. Such imaging was performed in 26 pts. Stress and rest images were displayed together, one directly on top of the other. Results: Myocardial perfusion was normal in 6 of these 26 pts and abnormal at either stress, or both stress and rest, in the remainder. In the pts in whom perfusion was normal, resting EF was 65.7+ 9.5% and increased post stress by' 2.3+2.9%. Among pls wilh abnormal perfusion, resting EF was 57A+12.6% and decreased by 5.7+ 9.1% post stress (p<.01 in response to stress). This additional information obtained by' gating was obtained at a cost of new potential artifact production on the static images. Rapid or irregular heart rates were challenging as was the simple addition of more equipment. When artifacts were seen or anticipated, an abbreviated nongated scan was obtained for comparison. In conclusion, "full view" gating and display can be used to compare ~est and post stress LV function. This additional information sbould be coupled with an awareness for the potential of new artifact production.

SIMULTANEOUS FUNCTION/PERFUSION ASSESSMENT BY TECHNETIUM-99M TETROFOSMIN : A POSSIBILITY OF VIABILITY DETECTION H. Kobayashi, T. Nakata, T. Sasao, K. Miyamoto, A. Dot, K. Tsuchihashi, S. Tanaka, and IC Shimamoto. Sapporo Medical University, Sapporo, Japan. To investigate the correlation between cardiac function and myocardial uptake of Tc-99m-labeled perfusion tracer, regional wall motion and myocardial perfusion were assessed simultaneously by gated first-pass scan ( F P ) and myocardial SPECT using Tc-99m-tetrofosmin ( TF ) in 40 patients with or suspected coronary artery disease. Regional wall motion score by FP was compared to that by 2-dimensional eehocardiography or contrast left ventrieulography (2DE/LVG) then myocardial SPECT was performed to calculate myocardial peffusion score and uptake of TF ( % peak count ) . FP wall motion Score showed 65% complete and 87% partially complete agreements with that by 2DE/LVG. When myocardial viability was defined as presence of residual wall motion, positive and negative predictive values of T F - F P were 88% and 71%, respectively, whereas myocardial viability was defined as presence of residual uptake of TF, positive and negative predictive values of T F - F P were 99% and 41%, respectively. The % peak count in akinetic or dyskinetie segment was significantly lower than that in normokinetic, mildly hypokinetic, or severely hypokinetic, segment ; 33-39% vs 79-81% vs 61-71% vs 52-67%, respectively. Thus, simultaneous function/perfusion imaging by TF and the quantitative analysis may contribute to differentiating asyncrgic or nonviable myocardium from dysynergic but viable myocardium.

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A S S E S S M E N T O F R W M A U S I N G GATED SPECT PERFUSION IMAGES. Olea E, Fuentes C, Orellana P, Quintana JC and Choag G. Nuclear Medicine Laboratory. Catholic University of Chile. RWMA was evaluated in 28 patients submitted to dual isotope myocardial perfusion study. Rest perfusion images (or "reinjection images") were obtained 18 hours after the injection of TI-201 at rest. Gated inmges from sestamibi pezfusion were obtained I hour post injection (stress or dypiridamol test) and ventrieular wall motion was also evaluated. Results from the gated SPECT (GS) analysis was compared with those obtained in one plane radiological ventrieulography (RV). RWMA by GS was fotmd in 19 ot~ of 20 patients. In the remaining patient RV showed a slight antero-apical hypokinesia with mormai ~obal ventrieular function. From 8 patients with normal RV, 7 had also normal GS. In one patient GS was abnormal, showing slight hypokinesia of the septum. Significant disease o f the artery supplying this territory was fotmd. In conclusion, our data sttggest flaat GS has a high overall accuracy (93%) and a high sensitivity and specificity (95% and 88% respectively) ha the assessment of RWMA.

STRESS-INDUCED ISCI-IEMIA IN HYPERTROPHIED APICAL WALL OF TIlE LEFT VENTRICLE IN HYPERTROPHIC CARDIOMYOPATHY: ASSESSMENT WITH GATED SPECT IMAGING USING 99~Tc-MIBI. K. Takeda, T. Yamakado, Y. Nomura, K.Matsumura, T. Nakano, T. Nakagawa. Mie University, Tsu, Mie, Iapan Stress-induced ischemia often occurs in hypertrophic cardiomyopathy (HCM). This study was designed to assess myocardial perfusion at a hypertrophied left ventricular apical wall in HCM after exercise using gated SPECT imaging with 9~'*Tc-2-methoxy-isobutyl-isonitrile (MIBI), as compared with non-gated SPEC£ imaging. Twenty-one pts with asymptomatic HCM without coronary artery disease and 5 volunteers were examined. According to apical thickness, the patients were divided into two groups: group A with apical thickness > 15 mm (n=l 1); and group B, with apical thickness < 15 mm (n=10). Thirty minutes after injection of 9~=Tc-MIBI (400 MBq) at peak exercise, non-gated and gated SPECT imaging was performed successively and followed by rest SPECT imaging 3 hours later with reinjection of 9~Tc-MIBI (600 MBq). Overall sensitivity tbr abnormal perfusion was higher in gated SPECT imaging than non-gated SPECT imaging (57% vs 29%). In gated SPECT imaging, 8 pts in group A showed 13 ischemia including 7 apical isehemia and 2 apical defects, while 4 pts in group B showed 3 ischemia and 1 defect. The count ratios of the apex to the other four left ventricnlar walls were significantly lower after exercise than at rest in group A, but not in group B or in the volunteers. The hypertrophied left ventricular apical wall in HCM appears to be predisposed to ischemia. Gated SPECT imaging was very useful in evaluating subtle myocardial isehemia.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

67.10 Assessment of Regional LV Function by Gated Tc-99m TETROFOSM1N SPECT AND FOURIER ANALYSIS. H.Maruno, M.Onoguchi, H.Toyama, K.Yoshioka, N.Komiyama, H.Murata, ToranomonHospital,Tokyo, Japan We have developed a new .quantitative program to generate automatically polar maps displaying several LV functional parameters (Functional G-maps) with gated SPECT and Fourier analysis. In this study, the utility of Functional Gmaps for chnical use was investigated. Fourteen normal subjects, 25 patients with coronary artery disease(CAD), and 12 patients with hypertrophic cardiomyopathy(HCM) were studied.Myocardial wall thickening and thinning in a cardiac cycle was analyzed for the optimal short axis images. The epicardial boundaries of LV were automatically defined and from the center of LV cavity 40 radii were generated, and a short axis image was divided into 40 segments. The regional time-activity curye was made from these sequential images. The rouowmg quantitative parametet~ were calculated in each se~rnent by means of the regional time-activity curve and funoermental Fourier component, and polar maps were generated using the oarameters of all short axis slices. 1)Minimum co~t (MIN), 2)Maximum count (MAX), 3)Count increase (t~) 4)% count increase (%CI), 5) Peak contraction rate (PCR) 6)Peak distension rate (PDR) and 7)Contraction time (CT) were calculated. CI, %CI and CT were useful for assessment of CAD and associated functional disorder. PCR and PDR could demonstrate myocardial contractility and distensibility in HCM. In conclusion, the Functional G-maps were useful for evaluation of regional LV function in various clinical situations.

Abstracts Tuesday afternoon, April 8, 1997

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67.12 ROLE OF STUNNED MYOCARDIUM IN RECOVERY OF FUNCTION AND PERFUSION DURING 6 MONTHS AFTER ACUTE MYOCARDIAL INFARCTION. Medolago G.,Costalunga A.,Piti A.,Rondi M.,Ghilardi A.

Nuclear Cardiology DPT. Ospedali RiunitL Bergamo, Italy. Spontaneous recovery of the perfusion defect assessed by Tc99" SESTAMIBI and associated improvement of regional kinesis several months following AMI was reported. Stunned, hybernating myocardium, and recruiment of collateral vessels were suggested in physiopathology of this phenomenon. In order to better understand this event. 18 consecutive patients (15 males and 3 females; mean age:52 ys) undergone direct PTCA for their first AMI were studied. In all patients complete opening of the infarct related artery (IRA) and TIMI 3 grade flow was obtained. Echocardiographic examination and resting regional myocardial perfusion and LV function assessed by Tc~')"SESTAMIBI SPECT were performed during the first week after AMI and repeated 3 and 6 months later. In all patients no events were observed during the follow-up period.; at 6th month coronary angiography performed in 4 patients showed patency of the IRA and persistent TIMI 3 grade flow in all angiograms. Results showed reduction of the extension and severity of the perfusion defect and concomitant improvement of the regional kinesis evaluated by wall motion index (WMI) at the third month (p< 0.05) and were unmodified at 6 months. No significant changes in EF and LV volumes, both assessed by echocardiography and RNA First Pass, were observed. In conclusion, data confirmed improvement of LV perfusion and contraction after AMI, and showed stunned myocardium as main factor in determining this phenomenon.

T U E S D A Y P M

67.11 ACUTE CHANGES IN LV-FUNCTION DURING PTCA. GLOBAL LVEF AS A MEASURE OF PRECONDITIONING? TB.Lindhardt, H.Kelb~ek, K.Saunamaki, JK.Madsen, P.Clenu-nensen, B.Hesse, N.Gadsboll. The Rigshospital. Copenhagen, Denmark. Purpose: To study the acute impact of PTCA on LV-function and the effect &two balloon dilatations (BD) on global LVEF and the ECG. Methods: LV-function was monitored in 40 patients with a miniature nuclear detector (Cardioscim®). Red blood cells were labeled with 800 Mbq 99mTc.Ten patients received two consecutive and identical BD. The ECG ST-segment deviations (STA) in the 12 leads were summated. Mean duration of balloon inflation: 113 +_45 see. Results: Pre-PTCA PTCA Post-PTCA LVEF: ,63 +-. 10 .51 +_. 14 * .65 -+. l 0 * * P<0.05 LVEDC: 78+- 19 79_+ 19 78-+ 19 LVESC: 29+ 12 39+ 16" 29-+ 12 LVEDC, LVESC: LV end-diastolic and end-systolic counts/l 0ms. 65% of the patients with LAD disease had a decrease in LVEF > 10 EF units, the corresponding figures for CX and RCA were 33% and 25%, respectively. The decrease in LVEF and the return to pre-PTCA levels occurred within seconds after balloon inflation and deflation. Compared to the initial BD the second BD was associated with significantly less decrease in LVEF (difference 7%, p<0.05) and also less summated STA (difference 30%, p<0.05). Conclusion: There was a significant and abrupt decrease in LVEF during PTCA explained by an increase in ESV with no change in EDV. The effect on LVEF was most pronounced in patients undergoing dilatation of LAD. No patients showed any sign of postPTCA stunning. In the 10 patients who received two BD our findings suggest that preconditioning can be induced in humans during PTCA.

67.13 CORRELATION OF A C U T E T C - 9 9 M SPECT IMAGING AND CORONARY ARTERY DISEASE AT Fossati, RS Morris, AW Ahlberg, GM Cyr, C McGiU, A Russell, MP White, FJ Wackers, GV Heller, Hartford Hospital, University of Connecticut, Hartford, CT, USA Limited data is available on the predictive value (PV) of acute myocardial perfusion imaging (MPI) in identifying coronary artery disease (CAD). We evaluated 150 patients utilizing Te-99m SPECT imaging within five hours of chest pain (CP). All patients underwent subsequent stress imaging, cardiac catheterization, or both. Images were read blinded. Results were correlated to determine the PV of acute MPI in identifying CAD for the total population, males and females, with and without CP during injection. Results: All Pts (n=150) M (n=91) F (n=59) + PV (%) 69 70 67 - PV (%) 76 72 82 Pts with CP (n=50) M (n=28) F (n-22) !+PV(%) 84 77 100 - PV (%) 68 60 75 Conclusion: The positive predictive value of acute Tc99m SPECT imaging improves in patients who are injected during active chest pain.

A P R I L 8

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67.14 Radianuclide Evaluation of Reperfusion in Acute M I . Correlation with The Available Reperfusion Criteria. Alia Abdel Fattah, Mohamed EI-Shafie, Areal Risk and Sherif Mokhtar, Critical Care Department, Cairo University, l~gvpt

T U E S D A Y

Early successful reperfusien is a cornorstone in the receut trend in managing patients (pts) with acute MI. Available clinical and laboratory criteria ofsueeessful reperfusian were compared to recent acute imaging teclmiqnes. We studied 16 pts with 1st acute MI, 14 were M, mean age (52.5:t:9.4 years), 10 had anterior and 4 had inferior MI. Clinical criteria of successful reperfusion were: relief of chest pain (CP) and regression of ST segment elevatian in ECG (S-T',b). Laboratory. criteria inchtded: Early peaking of CPKMB (CK) and TPA-PAI complex (TP) - a new fibrinolytic marker-. Decline following initial rise is sign of reperfusian. Fifteen to twenty mCi Tc-sestamibi (Mibi) was injected before institutian of therapy (Th), mad 3 planar images were acquired within 6 hanrs. A 2rid set of images were acquired 72 h. later. The myocardinm was divided into 15 segments allowing semiquantitativeanalysiswith a scoring s~ystem 0-3. An improvement of 10% or more li-om the initial score cousidered a siga of successful reperfusian. Twelve pts had patent infarct related artery (PA) while 4 pts had occhtded vessels in coronary angiograpby. The sensitivity and specificity of CP, ST~b, CK, TP and Mibi for detection of PA were respectively 25% - 25% (P = NS), 33% - 75% (P = NS), 50%-100% (P = NS), 58% - 25% (P = NS) and 100% - 50% (P < 0.006). Acute Mibi imaging is a sensitive teclmique in detection of PA and is mlperior to the available clinical. ECG and laboratory criteria of successful reperfusion.

Journal of Nuclear Cardiology January/February 1997, Part 2

67.16 ASSESSMENT OF AREA INVOLVED IN PATIENTS WITH ACUTE CORONARY SYNDROME B Y F- 18 FDG AND Tc-99m-SESTAMIBI DUAL ISOTOPE SPECT M. Moroi, A.J. Fischman, H.K. Gold, T. Yasuda, Massachusetts General Hospital, Boston, USA Assessing the area involved (A) in acute coronary syndrome (ACS) is an important task. It is often difficult to guess or demonstrate A in patients (pts) with multivessel coronary artery disease, prior bypass operation (CABG) or prior infarction (MI) despite the knowledge of the coronary anatomy.We investigated 71 pts with ACS admitted to the hospital due to MI (26),unstable angina (UA, 35) and congestive heart failure (CHF, 7). Forty-six of 71 (65%) pts had prior MI's. Eleven of 71 pts (15%) had prior CABG. Mean coronary artery disease/pt was 2.3. Mean LVEF was 50%. Pts were fasted over 12 hours and Tc99m-sesta MIBI and F18-FDG were injected 45 minutes prior to imaging.Glucose loading was avoided to suppress uptake by the normal myocardium and to enhance A. The results were as follows: A's were demonstrated in 90% and 65% of MI and CHF pts, respectively. In the UA group, treatment prior to FDG imaging made a significant difference; 70% of medically treated pts had focal uptake. However, PTCA-ed group resulted in only 20% of the population (p=.008). Regional perfusion defect of sesta MIBI images associated with focal FDG uptake suggests that the region's recent worst coronary insufficiency compared to the other diseased coronary artery territories.

P M A P R I L 8

67.15 RESIDUAL MYOCARDIUM AT RISK AFTER RECENT ANTERIOR MI: ASSESSMENT WITH MIBI SPECT AND INTRA CORONARY ECG. T.Fourme, S.Sebaoun, M.Faraggi, G.Gdmon, P.Colin, D.Le Guludec, G.Mott6, M.Slama. H6pitat A.BEclEre, Clamart, France. We assessed, 15 days after anterior MI, the residual myocardium at risk with 99"q'c-MIBI SPECT performed at rest and during PTCA, and compared with intra coronary (IC) ECG ST changes in 11 pts. SPECT was quantified by a bull's eye analysis using the difference of planimetered defect size (ABE) between baseline and PTCA reflecting the extent of myocardit|m at risk, and the difference in pathologic/normal uptake ratio (APNR) reflecting the severity of ischemia. Results : 1) the average myocardium at risk was ABE= 10_ 16% (ABE=0 in 2 pts), and APNR was 15+9%. 2) despite 10/11 pts had IC ECG changes > 1 mm (mean 8-+5 mm), IC ECG was not significantly correlated neither with ABE nor with APNR. Conclusion : during occlusion of LAD after anterior MI, the area at risk is highly variable ; IC ECG changes are not correlated to the extent and severity of PTCA induced ischemia.

67.17 INFARCT LOCALIZATION PREDICTION BY MEANS OF MYOCARDIAL PERFUSION TOMOGRAPHY AND CORONARY ANGIOGRAPHY. C. Santana-Boado, A. Garcla-Burillo, J. Candell-Riera, J. Figueras, J. Castell, J. Cortadellas, S. Aguad6. T. Canela, F.M. Dom~nech-Torn~, J. Soler-Soler. Hospital General Universitari Vail d'Hebron. Barcelona. Spain. Several angiographio studies have pointed out that the majority of myocardial infarcts do not develop in the coronary arteries with the most severe stenoses. However, there are not publications where it has been assessed if the infarct localization takes or not place in regions where a previous myocardial perfusion scintigraphic study had demonstrated more ischemia. With the aim of throwing light on this point 2112 myocardial perfusion tomographies performed in our Hospital from October 1991 to April 1996 and all the patients admitted in the Coronary Unit with acute myocardial infarct has been checked, in order to select those patients with infarct in which a myocardial perfusion tomography had been performed. Fifty-seven patients ( 6 4 + 9 years, 4 1 % women) with previous tomographic study carried out criteria of acute myocardial infarct ill their admission (24 anterior and 33 inferior and/or lateral infarcts}. 41 out of them (72 %) had also a previous coronary angiegraphy. The interval between the myocardial perfusion scintigraphy and the infarct was 2 0 2 ¢ 5 1 days, and between the coronary angiography and the infarct 251 + 72 days. techemic defeots more severe in anterior region and stenoses more severe in the left descending anterior coronary were attributed to anterior infarcts. Ischemic defects in lateral end/or inferior regions and stenoses more severe in the righ coronary or the oiscunflex were attributed to inferior and/or lateral infarcts. Results: In 51 of out 57 patients (89 %) there was coincidence between the infarct localization and the more severe ischemia in the previous tomography. The coincidence between the more severe coronary stenoses and the infarct localization was 83 % (34/41). Conclusions: A high coincidence between the infarct localization and tile more severe isehemia and coronary stenoses has been observed, in disagreement with previous studies. A reason that could explain these results is the relatively short interval between the myocardial infarct and the diagnostic procedures,

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Tuesday afternoon,April 8, 1997

$77

67.18

67.20

THE CLINICAL SIGNIFICANCE OF QS WAVE FORMATION BEFORE REPERFUSION THERAPY FOR THE RECOVERY OF R E P E R F U S I O N BY C O R O N A R Y R E V A S C U L A R I Z A T I O N IN ACUTE MYOCARDIAL INFARCTION. K. Watanabe, S. Watanabe, Y. Hashimoto, L Murata ,K. Hayakawa, S. Tanihata, H. Matsuo, T. Matsubara, Y. Matsuno, H. Oda, Y. Kotoo, H. Ohashi, Division of Cardiology, Gifu Prefectural Hospital, Gffu, Japan

CLANDESTINE IscHEMIA, SILENT ISCHEM(A AND ANGINA. QUANTITATIVE STUDY BY MEANS OF CORONARY ANGIOGRAPHY AND MYOCARDIAL PERFUSION TOMOGRAPHY. A. Garc[a-Burillo, C. Santana-Boado, J. CandelI-Riera, J. Castell, S. AguadB, T. Canela, J.M. Gonz&lez. F.M. Dorn~neoh-Torn~, J. Solar-Solar. Hospital General Un~versitar[ Vail d'Hebron. Barcelona. Spain. The aim of this study has been to assess the perfusion defects extension in patients with clandestine isshemia (perfusion defect without angina and no ST depression) comparing with those patients presented with silent ischemia (ST segment depression, without angina) and with those presented with angina. Eighty-five conseoutive patients have been studied, all with confirmed coronary artery disease demonstrated by means of coronary angiogrphy within a 3-month.period and free from previous myocardial infarction or from another cardyopathy. All patients underwent a symptom-Eimited exercise test on a b~oycle ergometer and a myocardla[ perfuslon ~°'Tc-MIBI SPECT (long protocol, rest performed at [east 24 hours after the exercise study). They were class~fled in three groups: GROUP 1:22 patients (57 ± 8 years. 3 womenl with angina. GROUP 2: 45 patients {56 4- 9, 5 women) with clandestine ischemia. GROUP 3:18 patients {59 ± 8, 2 women} with silent ischem[a. A semi-quantitative assessment of myocardla] uptake was made by two expert observers, which were bfinded as to the clinical, ang[ographic and exercise test results of the patient. The laft ventricle was divided into thirteen segments and uptake was eva[uated in each of them using a score from 1 to 5, according to the severity of the ischem~a. The scores in each segment were added up to establish the overall score (maximum score 65}. An angiographic score was also estab[ished depending on the degree of stenosis and its }ocal~zation (maximum score: 65). Results: Group 1 Group2 Group 3 One vessel disease 5 (23%) 16 (35%) 1 (5%) Two vessel disease 9 (41%) 12 (27%) 10 (56%) Three vessel disease 8 (36%) 17 (38%) 7 (39%) Angiographlc score 27 4- 8 25 ± 8 30 4- 7" Perfuslon score 26 ± B 24 ± 8 31 ± 9" =; p=O.OO8 Vs group 2. Without significant differences in the three group ergometric parameters. Conclusions: Neither myocardial perfuslon tomography nor coronary anglography show more extension of ischem]a or severity of the stenos]s in patients with angina as regards patients with silent or clandestine ischemJa. These last show less extension of ischemla and less severity of coronary stenosls than those with silent ischemia.

To evaluate the meaning of QS wave formation in terms of myocardial salvage effect by repurfusion therapy, the myocardial area at risk (AAR) and infarct size(IS) were assessed using 99mTc tetrofosmin (TF) in a consecutive series of 37 AMI patients with TIMI0 or 1 flow who subsequently underwent acute reperfusion therapy. SPECT imaging with TF was obtained to quantitate AAR and IS. The abnormality of perfusion was expressed using polar maps for sevedty(SS). Improvement was calculated by the following equations : %RA= [SS(AAR) -SS (IS) ] / SS(AAR) which implies the percentage of dsk area salvaged. Results._ Patients were divided into 3 groups ; the patients with QS in 1 or 2 leads(n=13), the patients with QS in at least 3 leeds(n=13), and patients with no QS wave (n=l 1) just before recanalization. No significant difference was observed in age, sex, hemodynamic severity and elapsed time from onset to reperfusion. Furthermore, the size of risk area, infarction, and salvaged myocardium showed no difference among 3 groups as shown in the table. No QS wave

QS in 1-2 leads

QS i n > 3

SS(acute)

1444-77

1274-64

1774-55

SS(chronic)

944-60

534-44

111 4-69

%RA

43.64-35

664-29.5

42.8___28.6

Concu!uMon. Even in the patients with QS pattern on acute ECG. reperfusion therapy provide the same amount of salvage effect as in the patients without QS pattern.

T U E S D A Y P M

67.19 SINGLE INJECTION OF 1-123-BMIPP REPRESENTS MYOCARDIAL PERFUSION AND FATTY ACID METABOLISM H Kobavashi, K Kusakabe, N Iguchi,S Hosoda,T Okawa Tokyo Women's Medical College, Tokyo, Japan The purpose of this study was to clarify whether initial distribution of BMIPP immediately after it's injection reflects myocardial perfusion. Methods. Twenty-seven patients with unstable angina peotoris (UAP) and 15 with acute myocardial infarction (AMI) were studied using dynamic BMIPP SPECT. Results. In the UAP group, all static BMIPP images showed reduced BMIPP uptake compared with resting TL images. However, initial distribution images of BMIPP (2-5 rain after injection) and resting TL images showed the same findings in 25 of 27 patients (93%). In the AMI group, static BMIPP images showed reduced BMIPP uptake compared with resting TL images in 8 of 15 patients. However, initial distribution images of BMIPP and resting TL images showed the same findings in 13 of 15 patients (87%). These results indicated that initial distribution of BMIPP, assessed 2-5 minutes after the injection, reflects myocardial perfusion well. Conclusion. Myocardial perfusion and fatty acid metabolism can be evaluated simultaneously using dynamic SPECT with single injection of BMIPP.

67.21 SESTAMIBI-SPECT AND GADOLINIUM-MRI TO DIFFERENTIATE PATENT FROM CLOSED INFARCT RELATED CORONARY ARTERIES. P Dendale, PR Franken, N Matheijssen, D De Greet, M Meusel, EE van der Wall, A de Roos. Free University Brussels (VUB), Belgium, and University of Leiden, The Netherlands. Both sestamibi and gadolinium are distributed in the myocardium by passive diffusion, but sestamibi is retained by active cellular processes. To determine if these tracers can predict the patency of the infarct related artery on contrast arteriography, 16 pts were investigated the week after a first acute infarction. Ultrafast contrast enhanced perfusion MRI was obtained after a bolus injection of Gadodiamide (0.1 mmole/kg) and time-intensity curves were generated for 16 segments in a midventricular short axis slice. Sestamibi uptake was quantified in the corresponding segments. Multivariate analysis showed a significant difference between patent and occluded arteries when combining time-to-max and washout slope of the gadolinium intensity curve. Sestamibi uptake was similar in both groups. We conclude that gadolinium, but not sestamibi, is capable to differentiate patent from closed arteries early after myocardial infarction.

A P R I L 8

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Journal of Nuclear Cardiology January/February 1997, Part 2

67.22

67.24

LEFT VENTRICULAR EJECTION FRACTION CALCULATED FROM GATED SPECT PERFUSION IMAGING: COMPARISON WITH CONTRAST VENTRICULOGRAPHY. Thomas A. Holly, Daniel C. Lee, Robert C. Hendel. Northwestern Univ. Med. School, Chicago, IL, USA.

STRESS MIBI GATED-SPECT FOR TE~ EVALUATION OF VENTR1CULAR FUNCTION. A COMPARISON ECHOCARDIOGRAPHY IN 95 PATIENTS.

Gated SPECT (GS) imaging allows the assessment of left ventricular systolic function during myocardial perfusion imaging. Software has recently been developed to calculate the global left ventricular ejection fraction (LVEF) from GS images. We compared the LVEF as calculated by GS perfusion imaging to that determined by contrast ventriculography (cath) in a group of 32 patients who underwent both studies within 3 months. 80%

]

70% ~ y = 0.8806x + 0,0088

,,=, ~

i

r = 0.79

5O% !

=

o%

93; 22:t455).Restthalliummmgeswere recorded30 rain to 20 hours(pts with MI ) after tracer injeetien (SPECT 32 fr, 40 see, 64x, 180~. Imedialelyaftca-, stress was induced:

Bruce protocol (57%3or pharmacologic (dipyridmnule35%:, dobutamineg%). M1BI was injectedat stress and one hour later GATED-SPECT was adquired (64x8 fr, 24

RESULTS: Global

40% {

T U E S D A Y

BACKGROUND: In CAD, MIBI GATED-SPECT brings essential information on perthsion and LV fimction. However, the its reliabili~" in assass~ent of LV function needs to be validated. We compared MIBI G-SPECT with 2D-eehocardiography. PATIENTS: 95 eortseontive stable patients were included with "known CAD (n:46 overall, 43 vdth previous MI) or chest pain suggestiveof CAD (n:49). ECHO and GSPECT with mean interval of 5 weeks (max. 24 wk). 57 were male and 48 feanale. Age from 25 to 76 y (mean 61 y). Five additional patients were discarded beeanse of bad echo~aphie window, l 8 patients ( 19 %) had window problemsbut could be included. METHODS: The dual rest thallium - stress IvflBIprotocol was used (Bennan, JACC

segmenta.Regional(simpifiedsegmanmtion~,stem: ANT, APX, LAT, INF) and global functionwas scoredfor both ECHOend G-SPECTusinga fourpoint scale:0-nomml,lmild, 2-moderate, and 3-ssvere depression. Blinded assessmentwas done by two observers for each technique. Agreementbetweenthe two techniques was evaluated using the Kappa analysis,and the percentageof exact eorr¢latien,the percentageof withinone-gradecorrelation,and an indexof weightedcontributionto non-agreement.

• ,.',,,.~" .g

M Fmile,D Pereferrer*,MT Luque, E ]_arrousse*,L Rubin,V Valle=,J Riba DepartmenL~of ~VuclearMedicine and Cardiology*. Hospital Universitari Germans Trias i Pujol. Bodal~a, Borcelon, Spain.

see,64x, I$0¢).ECHO was performed by either one of two experienced cardiologists, using standard viewS.long axis, short axis, apical 4 chamber and 2 chamber) and,

t,

A

10%

20%

30% 40% 50% Oath EF

SS% 70%

LEFT WITH

80%

GlobalM1pts

Kappa 0.67

0.68

%Agrcent. 80

78

%lgrade A. 100

100

%NoAg.tndex 68•32

73•27

Regional ANT 0.56 80 95 74•26 Regional INF' 0.55 76 87 63•37 CONCLUSIONS: Asses.~nentnfI.V function with MIBI G-SPECT is validated against

LVEF calculated by GS correlates well with that determined by cath. Therefore, in addition to myocardial perfusion data, GS also provides a useful noninvasive determination of global left ventricular systolic function.

2D-ECHO in the clinical ~tting. High Kappa and agreementpement ",alues were w.hiev~l.MIor isshemiadid not havea definiteinfluance. Of the limitednon-agreement, the weightof G-gPECTwas higherthan ECHO,meaningthat it tends to detectmoreLV

67.23

67.25

AUTOMATED CALCULATION OF EJECTION FRACTION

ACCURACY OF LEFT VENTRICULAR EJECTION FRACTION MEASUREMENT FROM GATED Tc-99m-SESTAMIB1 M Y O C A R D I A L SPECT: V A L I D A T I O N W I T H F I R S T PASS R A D I O N U C L I D E A N G I O G R A P H Y

function abnormalities.

P M A P R I L 8

FROM GATED T C - 9 9 M SESTAMIBI IbIAGES - COMPARISON TO QUANTITATIVE ECHOCARDIOGRAPHY

Diane R. Zanger, Anish Bhatnagar, Eva Hausner, Maria F. Botello, Clay E. Nuquist, Neil J. Weissman, Manuel D. Cerqueira. Georgetown University Medical Center, Washington, DC, USA Gated Tc-99m Sestamibi SPECT (GSPECT) imaging allows automated computer calculation of left ventricular ejection fraction (EF) and volumes. We compared the Cedars-Sinai quantitative GSPECT method to disc biplane quantitative echocardiography in 35 patients having studies within 1 month of each other. Results: EF End Diastole (ml End Systole (roll SPECT 55.1 (+ 16 103.6 (_+64) 53.9 (:1:60) ECHO 58.0 (+ 14 100.2 (_+35) 43.4 (+ 26) r value 0.79 0.88 0.91 There were no statistical differences between the two methods. Conclusion: the fully automated GSPECT calculation of EF is accurate and allows functional assessment from peffusion studies that is comparable to the results from quantitative echoeardiography. The ability to quantify systolic function and volume from GSPECT studies may obviate the need for echocardiographic measurements of EF.

(FPRA).

Sung M. Kim, J a m e s J. Zhang, Charles M. Inteazo. Thomas Jefferson University Hospital, Philadelphia, PA. USA Tc-99m-sestamibi provides assessment of both myocardial perfusion and wall motion. W e compare the E F m e a s u r e m e n t from the gated S P E C T study and the FPRA to assess the accuracy of the E F from the gated SPECT. A total of 37 patients w e r e simultaneously evaluated with gated M I B I S P E C T and FPRA. The FPRA was obtained at test from a m u l t i c r y ~ a l camera. Gated myocardial SPECT was obtained with 8 frames p e r R-R i n t e n , ai in a 360 arc with a t r i p l e headed camera. EF from gated S P E C T was obtained by m a n u a l l y d r a w i n g the endocardial b o r d e r of myocardium at the 7.4 m m thickness mid v e n t r i c u l a r short axis slice from the end-diastolic and end-systollc frames. The results were c o r r e l a t e d with the E F obtained from FPRA. Seven studies ( 3 cases of gated S P E C T and 4 cases of FPRA) were technically inadequate, duc to e i t h e r poor counting statistics or poor bolus injection. These studies were excluded from the analysis. There was a good l i n e a r relationship bet3veen the two techniques ( correlation coefficiency: 0.88). EF from the gated S P E C T ranged from 24 to 73 % . W e conclude that resting E F measurement can be obtained from both techniques with high confidence. E i t h e r t e c h n i q u e can be used, depending on the clinical setting.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Tuesday afternoon, April 8, 1997

67.26

67.28

TROPONIN T LEVELS 72 HOURS AFTER MYOCARDIAL INFARCTION AS SEROLOGIC ESTIMATE OF INFARCT SIZE: COMPARISON WITH TL-201 REST SClNTIGRAPHY J. Zehelein, R. Zimmermann, T.J. Dengler, B. Martinovic, H. Riedling, C.P. Tiefenbacher,W. K0bler, H. A. Katus. Departmentof Cardiology, University of Heidelberg,Germany.

A COMPARISON OF MYOCARDIAL PER_FUSION IMAGING AND ELECTRON BEAM COMPUTED TOMOGRAPHY IN ASSESSMENT OF CAD. ZM.Yao, XJ.Liu, RF. Shi, RP,Dai, SX.Zhang, YZ.Liu, ST.Li. Cardiovascular Institute and Fu Wai Hospital, CAMS and PUMC, Beijing China

After acute myocardial infarction, troponin T (TnT) is released considerably longer than cytosolic CK or LDH and the late release (>48 hours after onset of chest pain) appears to be less affected by early coronary reperfusion. Purpose of the present study was therefore to investigate the precision of a single measurement of circulating TnT 72 hours after onset of chest pain (TnTT~) in comparison to standard scintigraphic and enzymatic estimates of myocardialinfarct size. Methods:Quantitative SPECT TI-201 seinligraphy at rest was performed in 34 patients 2 to 3 weeks after a first myocardial infarction (GroupI: 14 patients without coronary reperfusion; GroupIh 20 patients with early reperfusion, achieved by thrombolytic therapy in 15 and by PTCA in 5). The number of myocardial segments with abnormal TI-201 uptake (indicating the individual extent of irreversible myocardial damage) was correlated to the TnT levels obtained 72 hours after onset of chest pain as well as to the peak levels ofCK, CK-MB and LDH.

Results: Group/ ~ GroupII

TnTu,

CK peak

r=.61,P=.021 ~

CK-MBpeak

LDH peak

r=.74,P<.001

Thus, a single measurement of circulating TnT 72 hours after onset of chest pain reveals a similar reliability as peak CK, CK-MB or LDH measurements (dedved from serial serum samples) for the estimation of myocardial infarct size.

To compare the myocardial perfusion image (MP[) and electron beam computed tomography (EBCT) in assessment of coronary artery disease (CAD). 43 pts(27 to 64 yrs) were studied. 9 pts had normal coronary angiogranl(CAG),34 pts had CAD (11 with single, 6 with double and 17 with triple vessel disease). All pts underwent Tc-99m MIBI SPECT(stress-rest), EBCT and CAG. MPI was performed using Siemens multiSPECT EBCT was performed with Imatron C-150 scanner. The density>130HU foci>lmm 2 on coronary artery was defined as abnomaal. The results demonstrated as following. SPECT EBCT MPI score p value Sensitivity(%) 83.3 69.0 <0.05 Specificity(%) 94.7 79.0 <0.01 Accuracy(%) 88.4 72.8 <0.01 Calcium score 0.6759 <0.001

$79

k

3" L~

E S E

¥ F IV 67.27

67.29

3D-FUSION IMAGE OF 3D LEFT VENTRICLES FROM FDGPET AND CORONARY ARTERY TREES FROM BIPLANE ANGIOGRAPHY: Th. Krause, R. Fischer, U. Solzbach, E. Moser. Departments of Nuclear Medicine and Cardiology, University of Freiburg, Germany.

IN-III-ANTIMYOSIN-SZINTIGRAPHY (AM,S) AND t~q)(~ffYOCARDIAL BIOPSY IN PATIENTS WII~I SUSPECrED MYOCARDITIS (MS). W. Gerhards, D.H. Antoni, D. Baumann. Khs Mfinchen-Bogenhausen, Munich, Germany,

Assignment of nuclear cardiac images and coronary angiography is far from being ideal. Consequently, a three-dimensional (3D) image fusion technique has been developed on the basis of a conventional biplane multidirectional isocentric angiography and a conventional FDGPET / Tc-99m MIBI SPECT acquisition. After 3D segmentation of the left ventricle tracer uptake is calculated and displayed on the epicardial surface. For 3D reconstruction of the coronary arteries from two corresponding angiographic views the vessels are segmented using 3D-B6zier-curves. With respect to the given reference system 3D tomographic and angiographic images can be merged after scaling and 3D translation. The results in 10 patients with single as well as multi-vessel disease show good correspondence of impaired myocardial FDG-uptake as well as MIBl-uptake and pathomorphology of the coronary vasculature. The hemodynamic implication of coronary artery stenoses becomes directly obvious and Myocardial metabolism can be read referring to the coronary arteries as a "coordinate system". Fusion of 3D-images of the myocardial FDG/MIBI-uptake and the coronary artery tree permits an optimal morphologicalfunctional evaluation of coronary artery disease.

We examined the s i g n i f i c a n c e o f /~S in 50 p a t i e n t s (pts) with suspected MS ( c l i n i c a l h i s t o r y l e s s than 6 months) and compared t h e s e r e s u l t s with the outcome o f h i s t o p a t h o l o g y

after myocardial biopsy. R e s u l t s : Biopsy &MS-pos. acute MS 8 c h r o n i c MS 4 h e a l i n g MS 5 healed MS 3 7 other 5 normal 4 t o t a l pts 36

AMS-neg. 0 0 2 7 1 2 2 14

Summary: 1 . I n j u r y o f myocardial cellmembrane caused by acute or c h r o n i c i n f l a ~ a t o r y a l t e r a t i o n s leads t o p o s i t i v e /~IS. 2. P o s i t i v e AMS cannot d i f f e r e n t i a t e between MS and d i l a t i v e c a r d i o ~ o p a t h y ( ~ ) with c o n t i n u i n g myocyte damage. 3. I n c r e a s i n g b i o p t i c h e a l i n g c o n d i t i o n s lead t o d e c r e a s i n g p o s i t i v e /~S. 4. A d e f i n i t i v e n e g a t i v e Mt3 excludes acute and c h r o n i c MS i n our f i n d i n g s .

F F I L

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T U E S D A Y

Abstracts Tuesday afternoon, April 8, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

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67.41

DETERMINATION OF I~JGHT VENTRICULAR EJECTION FRACTION: MRI VERSUS RADIONUCLIDE VENTRICULOGRAPHY S. Warm, Y. Lin, A. Narasimhan, C. Sampson, A. Shimakawa St. Luke's Medical Center, Milwaukee, Wisconsin, USA

VIABILITY ASSESSMENq" WITH G A T E D $PECT: ROLE OF M Y O C A R D I A L THJCKENTNG ANALYSIS IN WALL MOTION RECOVERY PREDICTION. T.Massardo, P.Hidalgo, P. GonzAiez, R.Alay, P. Humeres, J. Jofr& University o f Chile Hospital, Santiago-Chile.

Right ventricular ejection fraction (RVEF) can be measured using various methods. However, due to the irregular shape of the right ventricle and its location, none of the methods is entirely satisfactory. MRI is a multiplanar technique which may be especially useful in visualizing the right ventricle. The purpose of this study was to determine the correlation of RVEF measured using breath-hold Cine MR with that obtained from radionuclide ventriculography. 40 patients with history of heart disease underwent first-pass radionuclide ventriculography and breath-hold segmented Cine MR for measurement of RVEF. Short axis cardiac images were acquired using breath-hold segmented Cine MR acquisition with 9-19 temporal phases. The total acquisition time is about 100 breathholds. Systolic and diastolic images were analyzed and RVEF measured using Simpson's Rule on a workstation. Each patient's image set was analyzed three times. The intraobserver variability, measurement difference, and coorelation coefficient are 3.8+1.7 (%), 3.5+5.5 (%), 0.73 for RVEF. In conclusion, MR cardiac RVEF measurements correlate well with radionuclide ventriculographic measurements.

The objective was to evaluate the abilily o f myocardial thickening (T) to predict wall motion recoveff after revascularization (R) in 35 patients submitted to angioplaty or bypass grafting. All had abnon~aal segments in contrast ventriculography (30 with myocardial infarction). Wall T (count method) was obtained from an 8 frame gated SPECT at rest after 370 M B q o f Tc99mSestamibi. Circumferential T profiles in left ventricular short axis were compared to a 40 non:qaI data base. Regional motion recovery, was documented with 2D-Echo pre and 2 m post R. Only segments with R were analyzed: 37% o f them improved. There was no T difference between segments with or without improvement; 75% o f se~aaents with improvement and 41% without were under I sd o f the nomaaI Y mean.. Respectively, 56% and 24% o f segments were under normal T range. Concluding, for viability assessment, isolated quantitative myocardial Y with Sestamibi does not predict motion recovery after R.

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ENHANCED DETECTION OF MYOCARDIAL VIABILITY BY TECHNETIUM-99m-TETROFOSMIN SPECT A F T E R N I T R A T E ADMINISTRATION. A.Flotats,I.Carrif,M.Estorch, LI.Bern~,A.M.Catafau,C.Marf, M.Ballester.

180 ° VERSUS 360 ° TL-201 REST-REDISTRIBUTION SPECT TO PREDICT FUNCTIONAL IMPROVEMENT AFTER CABG/PTCA.

Hospital de Sant Pau. Barcelona, Spain. To assess if nitrate administration enhances the detection of myocardial viability by 9°~Tc-Tetrofosmin (TTF) SPECT, 15 patients with CAD, previous MI and LVEF <40% underwent 2°~TI rest-reinjection and TTF rest-postnitroglycerin (0.4 mg sublingual) SPECT studies, within 48 hrs. Tomograms based on the 3 spatial planes were divided into 15 segments and regional tracer uptake was quantitatively analyzed. Viability was defined as presence of tracer uptake >50% of peack activity at rest or after reversibility. The % of peak activity of TTF at rest correlated with tbat of ~-°aT1 (r=0.8, p < 0 . 0 0 l ) . On resting TTF studies 69 of the 225 segments that were analyzed had <50% of peak activity. 15% of these segments showed reversibility after nitrate administration, with increase in TTF uptake from 40.5%+10.5% to 59.2%_+10.1% of peak activity, p=0.01. All reversible segments after nitrates had viability criteria on 2°~T1 studies. Overall agreement between TTF with nitrates and "~°aTl-reinjection was 90%. An improvement in detection of myocardial viability with TTF was observed after nitrate administration which correlated with viability criteria on thallium studies.

Jeroen J Bax, Frans C Visser, Arthur van Lingen. Gerrit W Sloof, Cees A Visser. Amsterdam, The Netherlands. " I80 ° versus 360 ° data sampling is an ongoing discussion in thallium-201 (TI-20I) imaging. The aim of this study was to compare the relative merits of 180° and 360 ° TI-201 restredistribution (RR) SPECT to predict functional recovery after revascularization. 24 patients underwent TI-201 RR SPECT. All patients underwent revascularization (17 CABG, 7 PTCA). Regional wall motion was assessed by echo (13-segment model) before and 3 months post-revascularization. The 180° data (45 ° RAO-to-LPO) were reconstructed from the 360 ° data. Polar maps were reconstructed (13 segments) and compared with 180° and 360 ° normal databases. Segments were considered viable when TI-201 uptake was normal, when significant redistribution occurred or when the TI-201 activity exceeded a certain level. Optimal values for redistribution or T1-201 activity ' to predict functional improvement after revascularization were assessed by ROC analysis. Of the 106 dyssynergic segments, 36 segments improved and 70 did not. The optimal cutoff values for redistribution on the late TI-201 image to predict improvement were 5% for 360 ° and 7% for 180°. The optimal cutoff value for TI-201 activity on the late image was 75% for both 360 ° and 180° . The sensitivities for 180° and 360 ° TI-201 RR to assess improvement after the revascularization were 72% and 69%. whereas the specificities were 70% and 73%. Thus, 180° and 360° TI-201 RR have a comparable diagnostic accuracy to predict functional recovery after revascularization.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Tuesday afternoon, April 8, 1997

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67.45

GATED SPECT WITH TC-99M SESTAMIBI AND LOW DOSE DOBUTAM1NE FOR THE DETECTION OF MYOCARDIAL VIABILITY A.Bentrup,M.Engel,D.Hartung,W Hartung,R. Coenen,H.Otto, C.Huth Otto yon Guericke University Magdeburg, Germany

CONTRACTILE ANq) METABOLIC RESERVE EN RELATION TO COLLATERALISATION Zs. K6szegi, L Voith, I. i~des, Sz. Szakall, L. Tron Medical School University Debrecen, Hungary Contractile reserve elicited during postex'trasystolic potentialisation and F-lS-fluoro-deoxy-glucose (ISFDG) uptake were compared in relation of coronary collateralisation in segments related occluded coronary artery. 28 pati~ats with previous myocardial infarction were involved. Data from coronary angiography0 roentgeu ventficulography and in 7 cases from ~SFDG-PET were analysed. The collaterals were evaluated as well developed: grade 2-3 (group A) or not appropriate: grade 0-1 (group B). During ventriculography sigmficant contractile reserv was detected only in the presence of collaterals: after a spontaneous ex~trasystole the wall motion abnormality score decreased from 3,52 + 1,6 to 1,55 =k 1,06 (p=O,004) and from 3,08±1,76 to 2,96±I,72 (p=0,86) in group A and B, respectively.-ARer glucose loading the PET investigation revealed significantly higher metabolic activity in the infarcted segments of group A than in the regions of group B: 68,9±13,5% vs. 43,6:kl 9,8% (p=0,001, n=37). The results suggest that the presence of collaterals in infarcted segments supplied by occluded coronary artery predicts myocardial viability in concordance with metabolic and contractile reserve.

The present study sought to evaluate the accuracy of a new, combined perfusion and function testing in the detection of hibernating myocardium We investigated left ventricular perfusion and systolic thickening ratio (STR) in 140 myocardial segments of l0 patients before and after coronary revascularisation. In 6 only pharmacological treated patients initial and follow-up tests were performed within 3-6 months. Rest gated SPECT was obtained lh after injection of 15 mCi Tc99m Sestamibi under the infusion of 5-10g kg/min dobutamine during acquisition and without dobutamine next day. Myocardial count increase rate between enddiastolic and endsystolic frames was calculated and related to wall thickening. Gated SPECT was considered positive for hibernating with inotropic reserve if STR reached _<20% under dobutamine by persistent perfusion deficit in matching segments.Results.After revascularisation in 85/101 dependent vascular territories a significant improvement of STR was found (p<0.05). In 51/58 segments without revascularisation only minimal changes in STR could be proven. We conclude, that assessment of Tc99m Sestamibi gated SPECT under dobutamine may predict the recovery of myocardial contractile function after coronary revascularisation.

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67.46

MYOCARDIAL VIABILITY: A COMPARISON OF TC-99M SESTAMIBI GATED SPECT IMAGING AND REST-REDISTRIBUTION THALLIUM MG Levine, MP White, B Share&, A W Ahlberg, CC McGill, S Gift, D Waters, and GV Heller. Hartford Hospital, University of CT, Hartford CT

SEGMENTAL PERFUSION AND FUNCTION MATCHING IN CAD PATIENTSBY 2"IANDTo-BLOODPOOLDUALISOTOPEG-SPECT A. Constantinesco, L. Mertz, P.Germaln,B. Brunot. Hautepierre Hospital, Strasbourg, France

In comparison with rest-redistribution thallium (RR), gated SPECT imaging with Tc-99m sestamibi (GSI) allows simultaneous assessment o f perfusion and left ventricular function. We prospectively compared these techniques in assessing myocardial viability. In 10 patients who underwent CABG, 23 revascularized territories were examined by three observers without patient information. Predicted myocardial viability based on these studies were validated with post-operative perfusion scans. viable nonviable l sens. spec. pos. pred. val. GSI 15/18 4/5 83% 80% 94% RR 14/18 3/5 78% 60% 88% kappa (comparing R R with GSI) = 0.59 Conclusion: G S I is a useful and accurate tool to assess myocardial viability. It compares favorably with RR and has the advantage of providing an assessment of left ventricular function.

Methods: 17 CAD patients (13 with previous MI) and a control group of 3 normal volunteers were investigated. They received, 15 minutes after a 20IT1 stress/redistribution with reinjection protocol, 900-950 MBq of 99mTc-HSA for blood pool labelling. 8 frames/R-R interval were recorded in G-SPECT mode with three windows: window A with 20% centered at 71 keV for 201T1, window B with 10% centered at 105 keV for Tc scatter contamination and window C centered at 140 keV with 20% for 99mTc. Non gated, crosstalk corrected, 201TI SPECT perfusion images were reconstructed according to a normalized projection by projection subtraction of data of windows A and B. G-SPECT data of window C were reconstructed with the same reconstruction limits allowing topographic correlations of left ventricular wall motion and perfusion. The myocardium was divided in 20 segments. Perfusion was expressed in % of thallium uptake and function corresponded to diastolic to systolic shortening normalized by end diastolic volume. Results: Segmental comparison of uncontaminated versus contaminated and corrected 2013"1images showed for the 17 patients an overall agreement score of 93o~ with a kappa statistic of 0.76 +/0.06 when normal perfused segments were excluded. Segmental matching of perfusion versus function at rest showed no correlation for the 10 patients with a preserved ejection fraction of 59% +/- 8% and for control group. For the remaining 7 patients with an ejection fraction of 34% +/- 10% there was a linear correlation bem'een perfusion and function (r2 = 0.61). Conclusions: Our study suggest a low perfusion hypokinesis matching linear dependance in CAD patients whis low ejection fraction.

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Abstracts Tuesday afternoon, April 8, 1997

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67.49

Te-99m-MIBI UPTAKE DURING LOW-DOSE DOBUTAMINE IN DYSFUNCTIONAL VIABLE MYOCARDIUM

REDISTRIBUTION OF Tc-99m-TETROFOSMIN FOR THE DETECTION OF RESIDUAL MYOCARDIAL VIABILITY J. Lipiecki, V. Bourgeois, B. Citron, D. Mestas, G. Tamosiunas, D. Scetlier, J. Ponsonnaille, A. Veyre, J. Maublant. Centre J. Perrin, Clermont-Fd, France.

G. Marcucci, aM. Leoncini, M. Silvestri, ^M. Magni, A. Arena, ^A Traini, ^D. Mondanelli, ^L. Bini, C De Gaudio, ^M. ]Paoletti, ^L. Bardazzl, ^S. Amidei,^A Petrella, A Mennuti. Nuclear Medicine and ^Division of Cardiology -Prato Hospital.

T U E S D A Y

Journal of Nuclear Cardiology January/February 1997, Part 2

To evaluate the effects of low-dose dobutamine (i0mcg/kg, DOB) on perfusion (Tc-99m-MIBI SPET) and function (2DECHO) in asynergic viable myocardium, 27 patients with coronary, artery disease and severe regional dysfunction were studied at rest and during DOB. MIBI uptake was graded from 0 (normal) to 4 (absent); regional function was scored from 1 to 4. Left ventricle was divided into 2 vascular territories. DOB elicited contractile reserve in 19 of 36 asynergic vascular territories (DOB+). Nineteen territories in 17 patients were suceessfull revascularized: after intervention 12 showed functional recovery (viable,V+) and 7 no changes (fibrotic, V-). During DOB perfusion improved in 9 viable (7 DOB+) and in 2 (1 DOB+) fibrotic territories. Mean Tc-99m-MIBI uptake was: DOB+ DOB- V+ VBaseline 20_+6 19_+5 20_+7 18+5 Dobutamine 17_+6' 19_+5 17+8* 19+7 *p<0.05 vs baseline Conclusions: in as~aacrgicviable myocardium, contractile reserve elicited by DOB is often associated with an improvement hi Tc99-MIBI uptake. This suggests a possible link between the persistence of blood flow and contractile reserve.

The value of rest-redistribution of SPECT Tc-99mtetrofosmin was evaluated in the late phase of a myocardial infarction in 19 asymptomatic patients (pts) who underwent successful revascularization. Viability was detected by wall motion recovery at contrast ventriculoangiography and centerline analysis. SPECT data were analysed by automatic sectorization and comparison to a normal data base. At rest, the mean activity per sector in the territory of the related artery was not different in the 12 pts with evidence of viability and the 7 others (-4.2+2.2 vs -6.7+4.4, N.S.), but the difference was significant at redistribution (-5.7+_2,5 vs -10.1+_4.2, p<0.05). With a cut-off set at -4SD, the sensitivity, specificity, PPV and NPV were 82%, 83%, 90% and 71%, respectively. In conclusion, Tc-99mtetrofosmin at redistribution is a good predictor of residual myocardial viability.

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"~'Tc-TETROFOSMIN SPECT AND '~I-BMIPP SPECT A R E U S E F U L PREDICTORS FOR EVALUATING M Y O C A R D I A L V I A B I L I T Y A F T E R REVASCULARIZATION FOR ACUTE MYOCARDIAL INFARCTION Y. Arai, S. Mizuno, M. Ohnaka, and K. Yamamoto*, Fukui Cardiovascular Center and Fukui Medical School *, Fukui, Japan

REST-REDISTRIBUTION TI-201 SPECT TO PREDICT FUNCTIONAL RECOVERY: RESULTS FROM AN ANGIOGRAPHIC FOLOW-UP STUDY J. vom Dahl, K.-C. Koch, G.Schulz, S. Verhasselt, E. Ostwald, U. Btill, P. Hanrath. University of Aachen Hospital, Aachen, Germany

Accurate noninvasive predictor of myocardial viability (VI) is of paramount importance for the patients (pts) who will benefit most from revascularization(R). Our purpose was to c l a r i f y the usefulness of "mTc-tetrofosmin myocardial SPECT (MYO) and '-'~I-BMIPP SPE .CI'. (BM) for evaluating VI after R. We examined 25 pts with acute MI (17 males, 56___13yr, LAD/RCA: 20/5). Direst PTCA sigmficantly decreased the stenosis rate from 99.8 _ 0.5% to 28.0 -+ 12.0%. On MYO and BM, the region of interest (ROY) in the left ventricle was regarded as [ to 5 segments of the American Heart Association (AHA) classification on LVG, and uptake was expressed as the defect score (DS) (1: normal, 2:mild reduction 3: moderate reduction 4: defect). On LVG, wall motion was q u a n t i t a t i v e l y d e t e r m i n e d by the centerline method to evaluate improvement. Before R, 73 segments were akinetic. 48 of 73 segments (66%) improved wall motion by 1 SD or more on follow-up. Sensitl'vity, specificity, and accuracy of MYO and BM were 100% and 53%;71% and 90%; 84% and 74%, respectively. The segments with DS 4 on MYO did not improve in wall motion at all. We conclude that both MYO and BM are useful predictors of VI after R. B e s i d e s , the recovery of the myocardial flow in the myocardial infarted area is essential for VI.

To evaluate the predictive value (PV) of rest/3 hour redistribution (RED) TI-201 SPECT in patients (pts) with CAD and regional wall motion abnormalities (RWM), 35 pts (61_+6 years, EF 41+7%) underwent angiography 4+1 months after revascularization. RWM was assessed by a score from 1 (normal) to 5 (dyskinefic). Only regions without restenosis or graft failure were analyzed. A score improvement >1 was defined as functional recovery. T1uptake was analyzed in 25 regions, combined for coronary territories corresponding to angiography, and normalized to the region with highest Tl-uptake. Tl-uptake at RED had the highest PV for functional outcome. Tl-uptake _<40% had a negative PV (NPV) of 100% and Tl-uptake>70% revealed a positive PV (PPV) of 100%. In regions with severe dysfunction (baseline score >_3), ROC analysis revealed a 50% Tl-uptake at RED as best discriminator for missing or preserved viability with a PPV of 73% and a NPV of 86%. Combined analysis of rest/3hour TI-RED did not increase the overall PV since Tl-uptake in regions with recovery of RWM was 66+17% early and 67-+14% at RED, and was 47_+10% early and 46-+12% at RED in regions without functional change. Thus, quantitative analysis of Tl-uptake at 3 hours RED can be used for viability assessment.

Journal of Nuclear Cardiology Volume 4, Number l, Part 2

Abstracts Tuesday afternoon, April 8, 1997

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67.53

DEFINITIONOF THE OPTIMAL CRITERIA FOR VIABILITYDETECTION USINGQUANTITATIVETL-201 REST-REDISTRIBUTIONSPECT R. Sciagrh, GM Santoro, M.Matteini, A.Coppola, G.Bisi, P.F. Fazzini. Nuclear Medicine, University of Florence; Florence, Italy.

99m-Tc-TETROFOSMIN GATED 5PECT IMPROVES VIABILITY ASSESSMENTIN POSTiNFARCTIONPATIENTS

TI-20l rest-redistribution (Rest-Red) is widely used to detect viable myocardium, but the best criteria to differentiate hibernating segments from scars are not defined. This study compared the current approach based on activity thresholds in Rest or Red images with a more rigorous multiparametric approach using diseriminant analysis. In 26 patients with prior infarction and left ventricular dysfunction, TI-201 activity in Rest-Red SPECT was quantified as % of peak using a 13segment scheme. Wall motion was assessed on comparable segments using echocardiography: before revascularization 117 segments were akinetic; 64 of them improved after revascularization (= hibernating). ROC curves were constructed for Rest and Red activity to identify the most effective cut off values. Alternatively, Rest and Red activity and reversibility were submitted to multivariate discriminant analysis. According to ROC curves, the best cut off values for Rest and Red were > 60% and > 62%, rcspectiveIy. Discriminant analysis identified a discriminant function includin F = 16.2) and Rest (F = 1.93). Rest ROC Red ROC Discriminant Positive Predictive Value 71% 78% 79% Negative Predictive Value 60% 65% 71% Predictive Accuracy 65% 71% 75% These data suggest that : 1) Red activity is by far the most important parameter to be considered; 2) cut off values about 60% are more reasonable than the frequently used 50%; 3) the use of discriminant analysis improves the reliability of T]-201 Rest-Red SPECT.

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J. Lekakis. I~. Vezyrgianni, V. Prassopoulos, J. Oermanidis, J. Nana% N. Agrios, C. Papamichael, D. Charzifotiadis, S. Stamatelopoulos, S. Moulopoulos, P. Kostamis. "Alexandra' Universiw Hospital, Athens, Greece. Data on the usefulness of gated SPECT with 99mTcTetrofo~min (gSPECT) for evaluating myocardial viability are iac!.dr~g. We studied 22 patien=s (pts,~ with a recent myocardial tnfarction (Mb and segmental LV asynergy in myocardial segments supplied by >50% stenotic coronary arteries. Age was 57.--11 years, 2t were men and ejection fraction was 44+14%. All pts were examined by rest gSPECT and restredistribution TI-201 5PECTimaging. A 16-segment mode( was use~ .~or quantitative analysis of SPECT. A segment was COhSidered viable when TI-201 activity was >50% of maximum. Radiortuclide wall thickening (RWT} during gSPECTwas defined as increase in counts density at end-systole. Of 352 total segments 50 showed severe reduction of tetrofosmin uptake (<50%) while 142 mild or moderate reduction (>50%l; 38/50 (76%) of segments did not show RTW while 12/50 (24%) showed RTW; mos~ of the segments with severe reduction in tetrofosmin uptake and RWT (11/12, 92%) showed TI-201 uptake >50%. Of the I42 segments with mild-moderate tetrofosmin defects RWT was observed in 134/142 (94%); 131/134 (98%) segments showed TI-201 uptake >50% of maximum. !n cocn!usion, segments with mild-moderate 99mTcTetrofosmin defects usually appear to be viable based on TI20! imaging. Segments with severe tetrofosmin defects may be viabl~ if RWT is present.

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67.54

RELATION BETWEEN Tc-99m TETROFOSMIN UPTAKE AFTER NITRATE AND METABOLIC ACTIVITY IN PATIENTS WITH ISCHEMIC LEFT VENTRICULAR DYSFUNCTION.

!INFLUENCE OF CoQi0 ADMINISTRATION ON ISCHEMIC " MYOCARDIUM (EVALUATIONBY~-0ITI SCINTIGRAPHYAND 123I-BMIPP SCINTIGRAPHY) K.Tamura, N.Takamori. S.Okazaki, T.Nishiuchi, T.Matsurnoto, H.lguchi Health htsurance Narutn Hospital, Naruto, Tokushima, Japan

F. Menna, A. Cuocolo, A. Nappi, E. Nicolai, C. Mainolfi, A. Discepolo, MR. Grivet-Fojaja, M.R. Panico, B. Trimarco, M. Salvatore. Universit& Federico II, Napoli, Italy. Twenty-two patients with chronic ischemic left ventricutar (LV) dysfunction (ejection fraction 37_+10%) underwent Tc-ggm tetrofosmin SPECT (740 MBq iv) at rest and after nitrate administration (nitroglycerine 0.005 mg/kg per os) in two separate days. In all patients F-18 FDG PET was performed within one week. Tetrofosmin uptake and metabolic activity were measured in 22 segments/patient. On tetrofosmin imaging at rest, 72 (45%) dysfunctional segments showed a severe reduction (<50% of peak) of tracer uptake. Of these segments, 14 (19%) showed increased tracer uptake (>10% vs resting study) after nitrate and the remaining 58 (81%) did not change. All segments with severe reduction of tetrotosmin uptake at rest and increased uptake after nitrate showed preserved metabolic activity (FDG uptake >50% of peak). The majority (93%) of the segments with severe reduction of tetrofosmin uptake at rest and unchanged uptake after nitrate did not show metabolic activity (FDG uptake <50% of peak). Enhanced Tc-99m tetrofosmin uptake after nitrate in dysfunctional segments with severe reduction of tracer uptake at rest correlated with metabolic activity by PET imaging. Thus, Tc-99m tetrofosmin imaging after nitrate may improve the identification of severely ischemic but still viable myocardium in patients with chronic LV dysfunction.

Previously in 201TI scintigraphy, we showed that the redistribution of CoOl0 were compatible to the conventional 2o2TI images delayed by 24 hr. The purpose of this study was to reveal the cause of this phenomenone. The studies were performed on 35 patients who had sustained acute myocardial infarction 1 month or more prior to this study. The exercise 201TI scintigraphy and 1231-BMIPP scintigraphy were performed before and after the administration of CoQm. CoQn~ was administered to each patient 90rag/day for 1 week. The bicycle ergometer exercise test was performed using a multi-step incremental workload protocol. SPECT images were acquired immediately after exercise, and then again at 3 and 24 hr after exercise. The myocardium was divided into five regions, anterior, septum, apex, inferior and lateral wall. The redistribution of ~-()lTI and distribution of 1231-BMIPP were examined in these regions by gross inspection. After the administration of CoQm, the redistribution of 2ai TI were better than before administration of CoQ]o in 27 segments of 61 segments. At those areas where CoQlo administration led to an improvent in the redistribution of 2orTI, intra-myocardial accumuration of ~231-BMIPP was also increased. These results suggest that CoQm prevents dec]ease of ATP concentration in ischemic myocardium, and inprove 2olTI redistribution and 123I-BMIPP distribution.

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Abstracts

Journal of N u c l e a r C a r d i o l o g y

T u e s d a y afternoon, April 8, 1997

J a n u a r y / F e b r u a r y 1997, Part 2

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CLINICAL VALUE OF SCATTER CORRECFION FOR DUAL-ISOTOPE S P E C T W I T H I- 123 B M I P P A N D T L -

QUANTITATIVE Tc-99m TETROFOSMIN IMAGING IN THE DETECTION OF VIABLE MYOCARDIUM: A COMPARATIVE STUDY WITH TL-201 RE-INJECTION. E.Derebek, G.Qapa, E.Ozbilek, B:De{tirmenci, H.Durak. Dokuz EylOI University Hospital, Izmir, Turkey.

201. JT Yang, T. Tsuchida, Y. [shii, N. Sadato, K. Yamamoto, N. Takahashi, N Hayashi, Y. Yonekura, Fukui Medical School, Fukui, Japan

T U E S D A Y

Detection of mismatch between flow and fatty acid metabolism has been reported to be useful for assessing myocardial viability. Simultaneous data acquisition with cross-talk and scatter correction should be required for this purpose. To improve the image quality in simultaneous dual-isotope SPECT, we applied scatter correction by triple-energy-window (TEW) method. Dual- and single-isotope SPECT was performed in 71 patients with coronary artery disease. Dual-isotope SPECT images with and without TEW correction were compared with single-isotope images for qualitative evaluation using five-grade scoring. TO quantify the mismatch, the parametric divisional polar map of perfusion / fatty acid metabolism was generated. Segmental agreement of the score between dual- and single-isotope images were significantly improved by TEW method (p<0.01). Nine patients showed mismatch only with TEW correction. TEW method is practical for cross-talk correction, effectively improving the image quality in clinical studies. Simultaneous dual-isotope SPECT with TEW method is feasible to detect the mismatch quantitatively.

We aimed to investigate whether quantitative Tc-99m tetrofosmin (TF) SPECT imaging can be used in the detection of viable myocardium, comparing with TI-201 re-injection (RI). 42 patients with angiographically documented CAD who had at least one fixed segmental defect during conventional stress-redistribution (ST-R) TI-201 (3 mCi) SPECT imaging were included in the study. RI imaging initiated 10 min after redistribution study, injecting additional 1 mCi TI-201. Within a week after TI-201 imaging, rest TF (25 mCi) SPECT imaging was performed. All images were quantitatively evaluated dividing left ventricle into 9 segments. Segmental activity (SA) expressed as the percentage of maximum activity. More than 10% increment with RI study (reversible) was adopted as the criterion for viability, if the activity was over than 50% on RI image. Of 115 fixed defects on ST-RD TI-201 study, 41 (36%) were found to be reversible on RI image (TF SA=56+16%). In the remaining irreversible 74 (64%) segments on RI, TF SA was found as 45-/-13% (p< 0.01). Adopting more than 50% of SA on TF image as the criterion for viability, we found 80% concordance between RI and TF regarding viability. We concluded that quantitative TF SPECT imaging may have a clinical utility in the detection of viable myocardium.

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67.58

THE USEFULNESS O F L'F'FDG S P E C T IMAGING IN EVALUATING MYOCARIAL VIABILITY. H. Sato, T. Toyama, Y, Kaneko, T, Suzuki, R. Natal, K. Tomiyoshi, T. Inane, K. Endo, N. Ota, N. Kanazawa. Gunma University School of Medicine, Gunma Japan.

TC-99m-MIBI DIAGNOSTIC CAPACITY AND INCREMENTAL VALUE OF SYSTOLIC WALL THICKENING (%SWT) IN MYOCARDIAL VIABILITY (MV) ASSESSMENT. V Arja,A Sanddn, C Balestdni, A Canestd, V Balestdni.lnstituto Modelo de Cardiologia, FUCCADIM, C6rdoba, Argentina. MIBI myocardial uptake and %SWT are posed as tools capable of improving myocardial viability (MV) assessment.Objective: Analysis of MIBI-uptake diagnostic capacity and incremental value of %SWT to assess MV. Matedah 25 patients, with coronary disease, severe contractile dysfunction (SCD) (dyskinesia, amnesia, severe hypokinesia) and EF_<30%, were sent to lab to assess MV.ln all were performed: a) radioisotopic angiogram (RA), b) TI-201-SPECT, and c) rest-MIBI-gatedSPECT,rebuilt to MIBI non-gated(MIBI-NG) and MIBI-gated (MIBI-G).LV was divided in 9 segments(S),(correlating RA,TI201, MIBI-NG, MIBI-G). We obtained uptake% (U%): value of total counts of each S ~ t h respect to the S with maximal uptake.Definitions: Viable S (VS): U%>50%, Non-Viable S (NVS): U% <50%, and %SWT viable (SWT(+)) when it was >1%. Results. McNemar-test: in all 225 S, TI-201 had 14% of NVS, and MIBI, 8%. Non-coincident S: p<0.0017. In 121 S with SCD, TI-201 had 18% of NVS and MIBl,10%.Non-coincident S: p<0.003. Paired t-test:in S ~ t h SCD, TI-201 had 86% of VS, MIBI: 90%, and MIBI+SWT(+): 94%. In VS, TI-201 vs MIBI+SWI-(+) had significant difference (p<0.O02). Conclusions: MIBI showed < quantity of NVS than TI201MIBI+%SWT(+) showed a significant incremental value in relation to TI-201 images in VS detection.

We compared myocardial viability evaluated by 'SF deoxyglueose (FDG) SPECT in 20 old myocardial infarction patients with that evaluated by ~°"Tl SPECT (T) and ~3I- fl-methyl-iodophenyl pentadecanoic acid (BMIPP) SPECT (B) as imaging of fatty acid metabolism. FDG SPECT was performed after oral administration of glucose. Prom each SPECT image which was divided into 7 segments (set. s), the degree of accumulation of each radioisotope (RI) was visually classified into four grades of defect score (DS) (ranging from 0 as normal to 3 as severe defect). The %uptake in the same area was also quantitatively calculated. Regioual wall motion in the 7 segments was scored on left ventriculography according to the four grades of wall motion score (WMS) (ranging from 2 as normal to 1 as dyskinesis), and regional wall motion was compared with the rmlge and the degree of accumulation of R[ in each SPECT image. (Results) ¢~ WMS relative to the presence ( + : DS ~ 2 ) or absence ( - : DS =3) of accumulation of R[ in each SPECT.

I

B(+),T(+) ~(+),'r(-)l

FDGI+)I.6-+ 0,7(104seg.sl uone

B(-),Tf+)

I

B(- T{-

0.7 +-0.9(15seg.s)1-0.1+ 0.5(12seg.s

FDG(--I none / none I none ] 0(4seg.s) @ The degree of accumulation of myocardial R[ relative to regional wall motion. FDG B T lypokinesis DS 0,7-1-0.7 1.4-1-0.9" 1.0-+0.7" {24 segments) %uptake 77 -4-16% 62__+26%" 71 + 17%" &inesis to dyskinesis DS 2.1---+0.9 2.84-0.4" 2.4--+.0.8" 1.8..segments} %uptake 58-1-19% 31+22% ° 39--+20%"

( * : p<0.0001 vs FDG , " : p<0.005 vs FDG )

Tile range of accumulation of radioisotope in tile i n f a r c t e d a r e a was greatest for FDG, followed by T1 and then BMIPP. The degree of accumulation on FDG-SPECT in the area of decreased wall motion was greater than that on the other two procedurs. These results suggest that FDG-SPECT is useful for evaluating myocardial viability.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday morning, April 9, 1997

$85

67.59

84.2

THE VIABILITY STATUS OF THE LEFT VENTRICULAR (LV) ANEURYSMAL WALL.

PERSISTENT DEFECTS ATTHALLIUM-201 IMAGING AS PREDICTORS OF RESTENOSIS AFTER CORONARY STENTING R.Zimmermann, J.Zehelein, Ph.Wende, R.Mura, T.J.Dengler, C.P.Tiefenbacher, J,Hoffend, W.K0bler. Depts. of Cardiology and Nuclear Medicine, University of Heidelberg, Germany.

A. A1-Mohammad, N. M. Showell, M. Y. Norton, S. Walton. Cardiac Department, Aberdeen Royal Infirmary, Foresterhill, Aberdeen AB9 2ZB, Scotland, United Kingdom. Ventricular aneurysms are non-functioning dilated areas of the myocardium. If they are hibernating, then the associated LV dysfunction could be improved with revascularisation. Therefore, we investigated the presence of hibernating myocardium in the aneurysmal wall. Positron emission tomography (PET) criteria was used to determine myocardial viability. N-13-ammonia and F-l 8-fluorodeoxyglucose were the perfusion and the metabolic markers, respectively. Twenty patients (15 males), aged 46-87 years with LV aneurysms were studied. Discrete aneurysms involved 23 segments. A matched defect typical of non-viable myocardium was found in the aneurysmal wall in all the patients studied. Conclusion: The LV aneurysmal wall is non-viable. Revascularising the aneurysmal wall will not improve LV function.

SPECT dipyridamole thallium-201 imaging was performed in 63 patients at a mean of 10 -+4 days following successful emergency coronary stenting, All patients underwent quantitative angiographic follow-up (CASS II system). This was routinely performed 6 months after coronary stenting in 51 patients and, prematurely, at a mean of 103 days (range 8 to 194 days) in 12 symptomatic patients. Thallium scintigraphy revealed normal tracer uptake or reversible defects in 43 patients (Group I), and persistent defects in 20 patients (Group II). Angiographic data were comparable in the two groups both before and immediately after coronary stenting. At the time of angiographic follow-up, however, restenosis was significantly lower in Group I compared with Group II (median, 29% vs 48%; P=0.004), and restenosis _>50% occurred in only 6/43 patients of Group I but in 10/20 patients of Group II (14% vs 50%, P
Wednesday AM, April 9, 1997

84.3

Sessions 84 and 86-90

DISTAL REVERSIBILITY IN INFARCT-RELATED ARTERY TERRITORY DETERMINED BY SPECT TI-201: A SIGN OF COLLATERAL FLOW WITHIN THE OCCLUDED CULPRIT ARTERY P. Chouraqui, Z. Bril, M. Shechter, S. Livchitz, B. Rabinowitz, E. Di Segni. Sheba Medical Center, Tel Hashomer, and Tel Aviv University, Israel.

84.1 RELATIONSHIP OF REGIONAL MYOCARDIAL BLOOD FLOW TO MENTAL STRESS AND ISCHEMIA BY EXERCISE THALLIUM. J.A. Arrighi, A.H. Kao, M. Burg, R. Soufer. Yale Univ./VA PET Center, West Haven, CT, USA The mechanisms of mental stress (MS) induced myocardial ischemia in patients with CAD are incompletely understood. In order to examine the relationships between myocardial blood flow (MBF) response to MS, dipyridamole (dipy) flow reserve (CFR), and ischemia by Ex TI, we studied 6 pts with chronic CAD with quantitative N-13 ammonia PET at rest, during dipy stress, and MS. All pts had prior coronary angiography and exercise (Ex) TI scans. 7 regions (reg) had ischemia by Ex TI, and 6 reg had blunted MBF response to MS (MS:rest flow ratio _< 1). Of 7 regions (reg) with ischemia by TI, only 3 had blunted MBF response to MS. The 6 reg with a blunted MBF response to MS had a lower dipy CFR compared to reg with increased MBF during MS (1.5 vs 2.5, p<.05). This preliminary data suggest that blunted MBF response to MS by PET may occur in reg not ischemic by Ex TI.

Assessment of presence of flow within the myocardial infarction (MI) zone, is important for patient (pt) management. TI-201 reversibility distal to a fixed defect in the infarct-related artery territory, may be related to collateral flow to the occluded culprit artery. To test this hypothesis, we performed SPECT TI-201 studies in 69 consecutive pts after MI with an occluded (n=65) or critically stenosed (n=4) culprit artery. Group A (29 pts) showed reversibility distal to a fixed defect, while Group B (40 pts) had only a fixed defect. Collateral flow to the culprit artery was observed by angiography in 28/29 pts of Group A, and in 2/40 pts of Group B (Sn: 97%; Sp: 95%). Thus, T I - 2 0 1 S P E C T pattern of reversibility distal to a fixed defect in the infarct-related artery territory, is an accurate marker of collateral flow in pts with occluded or critically stenosed culprit artery.

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W E D N E S D A Y A M A P R I L

Abstracts Wednesday morning, April 9, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

84.4 SIGNIFICANCE OF INTRACORONARY MYOCARDIAL CONTRAST ECHOCARDIOGRAPHY PERFUSION ABNORMALITIES AFTER MI IN TIMI 3 PATENCY PATIENTS. M. Faraggi, D. Karila-Cohen, E. Brochet, D. Czitrom, P. Seknadji, D. Le Guludec. Bichat Hospital, Paris, France.

84.6

A 3-grade perfusion score obtained by myocardial contrast echocardiography (MCE) alter intracoronaryinjection of sonicated ioxaglate was performed in the acute phase of myocardial infarction (< 6 hrs) immediately and 9_+1 days alter restoration of TIMI 3 patency by PTCA (n=17) or thrombolysis (n=3). This perfusion score was compared to rest-redistribution thalliumSPECT results and to the improvement of a 4-grade 2D echocardiographicwall motion score (WMS) under low dose of dobutamine both performed on the 10th day. Acute MCE perfusion score correlated with the initial planimetered TI defect size measured on bull's eye polar maps (r=0.64, p<0.01) but neither with the pathological to normal thallium uptake ratios (PNR) nor with WMS. Conversely, predischarge MCE perfusion score correlated only with thallium PNR (r=0.61, p<0.01) and WMS (r=0.5, p<0.05). Conclusion: after myocardial infarction, echographic perfusion abnormalities are mostly related to the area at risk in the acute phase and to myocardial viabilityindices in predischarge.

Over a 3 year period, 106 patients underwent both planar stress and redistribution thallium perfusion imaging and coronary angiography at Avicem~e Hospital and were found to have normal coronary arteries. Of these 106 scans, 33 showed homogenous tracer uptake by quantitative analysis, and 73 showed mild (2030%) reversible or fixed defects. Of the 73 scans with defects, 28 were eliminated due to breast or diaphragmatic attenuation artifacts, LBBB, hot spots, LVH, LV dilatation, MVP, leaving 45 scans with a total o f 65 mild reversible defects. This population comprised 39 m e n and 6 women, mean age of 50L-9 yrs. Coronary dominance was determined using the Schlesinger classification. In the entire group o f 78 patients, 21% were left dominant, 33% right dominant, and 46% codominant. In the 33 pts with homogenous tracer uptake, 89% had codominance and 11% dominance, whereas among the 45 patients with mild reversible defects, 76% had dominance and 24% codominance. There was a significant effect of dominance on defect presence (p<0.001). To evaluate possible mechanisms for this observation, defect localization was evaluated. All defects were either septal (46%), inferoposterolateral (45%), or apical (9%). There was no difference in defect locations between the right, left, and codominant patients. These data suggest that coronary dominance m a y contribute to mild flow heterogencity during stress with mild reversible defects occurring in the "watershed" area between the right and left coronary arteries.

C O R O N A R Y A R T E R Y D O M I N A N C E AS A P O S S I B L E CONTRIBUTING CAUSE TO FALSE POSITIVE PERFUSION SCANS

Mohamed Alami, Leila Hajji, Rachid Ghannam, Mustapha Sadeli, Naima EIHaitem, Mohamed Benormar. Avicenne Hospital, Rabat, Morocco.

84.5

84.7

SIGNIFICANCE OF PROMINENT ATRIAL WAV~ ON. T H E EXERCISE MUGA FOR DETECTION OF CORONARY DISEASE E. Klainman, I. Hertz, S. Sclarovsky, M i s h m a r Hayarden and B e i l i n s o n Cardiac Institute, Givatayim, Israel. The aim of t h i s study was to evaluate the significance of a p r o m i n e n t atrial w a v e on the exercise M U G A L V filling curve for the detection of c o r o n a r y d i s e a s e in t h e p r e s e n c e of normal systolic function. T h i r t y - n i n e patients aged 3 5 - 7 0 y u n d e r w e n t exercise MUGA study, t h a l l i u m - 2 0 1 s c i n t i g r a p h y and c o r o n a r y angiography, and w e r e d i v i d e d into 3 groups: 1-10 pts w i t h n o r m a l angiogram; II-19 pts w i t h 1-vessel disease (>50% stenosis), a n d I I I - l O pts w i t h 2 - v e s s e l disease. Resultst Group I: all pts had a normal t h a l l i u m s c a n and no prominent atrial w a v e s on e x e r c i s e (exercise wave/rest w a v e = 1.34 ±0.2). G r o u p II: all pts but one h a d 1-3 r e v e r s i b l e f i l l i n g d e f e c t s on t h a l l i u m scan and p r o m i n e n t atrial waves e x e r c i s e / r e s t r a t i o - 2.03±0.8. G r o u p III: all pts but two had 1-4 t h a l l i u m f i l l i n g d e f e c t s and more p r o m i n e n t a t r i a l w a v e s exercise/rest ratio = 2.35±0.75. C o n c l u s i o n : T h e s e findings validate the use of p r o m i n e n t a t r i a l w a v e s on MUGA exercise LV filling curve as significant m a r k e r of c o r o n a r y d i s e a s e e v e n in the p r e s e n c e of n o r m a l systolic function.

A B N O R M A L ATP-STRESS TLSPECT IIVIAOING AND POOR CORONARY F L O W RESERVE IN SYNDROME X. T.AkirMtsu, K.Aldyoshi,K.ho, K.Kaneda, M.Hara, T.Sailmwa. First Dept. of Internal Medicine, Oita Medical Urdversity, Oita, Japan AIM: Abnormal microcirculation is suggested in syndrome X (SX) (an ginat pain. positive exercise test, normal coronary angiography and no evidence of vasospasm). We analyzed the flow heterogeneity and coro nay" flow reserve (CFR) in SX using adenosine triphosphate (ATP) stress test together with Tt- SPECT and intracoronaC¢ Doppler flow reserve measurements.Methods: 21 patients (pts) with SX (age 5 6 ~ 7y-eea's)underwent ATP (0.l 6mg/kg/min. intravenously) .stress T1SPECT. The results were compared with 6 normal subjects (age 58----7years). The blood flow velocities in LAD artery, was mordtored by us m g a Doppler-tipped guidewire, at rest and during maximum hyperemia induced by intravenous ATP (0.16mg/kg/min). CFR was catculated as the ratio of maximal to baseline flow velociD'. Results: Among 21 pts, 18 pts (86%) showed transient defects on stress image and I patient had an irreversible defect.Perfusion defects were observed in 20 areas (14 LAD areas. 5 R_CAareas, and I LCx area, respectively). CFR was mea sured in l 0 pts of SX group, who revealed transient defects in LAD area in stress TI-SPECT. CFR of SX pts was 2.1 ~0.3 and significantly lower compared to that of normal subjects (3.5±0.5). Coaclusinn: These results suggest that patients in SX present disturbance of coro nary blood flow assessed by an impairment of CFR. We conclude that _ATP-stressTt-SPECT is useful in detecting impaired CFR and abhor real microcirculation.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday morning, April 9, 1997

$87

84.8

84.10

ASSESSMENT OF RESTENOTIC LESIONS AFTER PTCA WITH CORONARY ANGIOGRAPHY AND MYOCARDIAL SPECT. Ch.Maunoury, C.Le Feuvre, G.Helft, F.Beygui, JP.Metzger, A.Vacheron. Necker Hospital, Paris, France.

STRESS ANrD REST GATED SPECT EVALUATION OF CAD PATIENTS :QUANTITATIVE AND "vISUAL COMPARISON A. Bestetti. C. Di Leo, L. Tagliabne. G.L. Tarolo Cattedra di Medicina Nucleare. Univcrsit5 degli Studi di Milano c/o HSPaolo

The aim of this prospective study was to assess coronary a n g i o g r a p h y in r e s t e n o t i c lesions after PTCA, with reference to m y o c a r d i a l SPECT. Quantitative coronary angiography and stress-redistribution TI-201 myocardial S P E C T w e r e performed in 64 consecutive patients 6+2 months after successful PTCA. A reversible perfusion defect in the territory of a previously dilated artery w a s c o n s i d e r e d as a positive SPECT. Digital computer-assisted c a l i p e r s w e r e used to q u a n t i f y restenotic lesions: percentage of stenosis (S) and minimal luminal d i a m e t e r (MLD). R e s t e n o t i c v e s s e l s w e r e narrower in patients with positive S P E C T (n=26): S = 53+15% and M L D = 1.3+0.5mm than in patients with n e g a t i v e S P E C T (n=38): S = 41+_20% and MLD -1.7+_0.7mm (P 5 0 % and in 38% of patients with M L D < I . 4 m m . S P E C T was positive in 33% of patients with S < 5 0 % and in 2 3 % of patients with M L D > I . 4 m m . In conclusion, quantitative coronary a n g i o g r a p h y failed to assess functional significance of restenotic lesions. Six month a n g i o g r a p h i c follow-up and PTCA for restenosis need previous non invasive assessment of myocardial ischemia.

The aim of this study, was to evaluate the accuracy (A) of regional myocardial ~,stolic thickening indexes (STI) assessed on stress and rest polar endiastolic (ED) and endsystolic (ES) maps obtained ~" GSPECT using 99mTc-Tetrofosmin (separate day), dual head digital camera and quantitative gated algoritlun. Each polar map was divided into 16 segments (seg).We defined the normal distribution of stress perfusion on the ED images of ten normal subjects.In a group of 22 consecutive CAD pts, with and ~ithout previous MI, who underwent coronary angiography,was evahiated A of this quantitative segmental analysis (QA) comparing it with perfusion and systolic thickening (ST) score obtained respectively on ungated and GSPECT polar maps ~ visual analysis (VA).Resnlts. No significant difference was found between QA and VA as concern the number of reversible (roy), fixed defects and normal seg.Overall A was non significantly higher for VA in respect to QA while the difference was significant in the detection of LAD stenosis (p=0.005), The seg with roy defects at VA and fixed at QA showed stress STI significandy lfigher than seg with rea, defects at QA and fixed at VA. Stress ST[ discriminated well the seg with preserved ST at VA. Stress and rest STI of seg with fixed defects in non infarcted regions were significantly higher than in infarcted myocardial regions, Conclusion. QA of ED and ES polar maps obtained by GSPECT and fast processing algorithms correlates well with VA of ungated images as concern pcrfusion. Stress STI add information to perfusion SPECT allowing to distingaaish true fixed and roy defects from attenuation artifacts.

84.9

84.11

CAVITY SIZE ENLARGEMENT IN TC 99M SESTAMIBI (MIBI) SPECT IN HYPERTENSIVE PATIENTS WITH NORMAL CORONARY ARTERIES.

Tc-99m ~

E.Milan, RCampini, A.Terzi, A. Vaccari, R.Giubbini. Nuclear Medicine Dpts, SpedaliCivil[ Brescia & FondazioneMaugeri, Veruno (No} Italy. Le~ ventricular (LV) hypertrophy(LVH) is a commonfinding in hypertensivepts. Augmented end-diastolic LV pressure causes an increase of resistances in subendocardial circulation which reign lead to an increase in likelihood of myocardial ischemia. LV cavity dilatation on 13-201 imaging is a marker of severe CAD due to transient LV dysfunction: this mechanism seems unlikely in MIBI studies, due to delayed imaging after tracer injection. We evaluated prevalenceand charastedstics of LV dilatationin post-stress MIBI SPECT in 21 hypertensivepts. with normal coronary angiograrnsin comparison to a Control group (C group) with less than 5% pro-test probabilityof CAD. The study group was divided into pts with (group 1) and without (group2) LVH. LV cavity size (VCS), expressed in arbitrary units, was determinedby automated program able to identify the inner LV border by thresholding method, inducible ischemia was

quantified by evaluation of gender matched polar maps. Results are summarizedin the following table: c group 4CS stress

group 1+2

w 251 _+106

y¢ VCS rest

229 + 67

group 1

group 2

180_+86/

151 +_63

206_+98

16o _+99F *~

68 + 23 J*~

243 + 55

!

IN O]~PARLNIq W f ~ I~U~IU~-201

Z. Burak, H. Akln, S. Buket, A. Sa~can, M. Argon, Y. Atay i. Durmz, Y. Da~n. Fge University ~ , ~URKEY. The aim of this study ~ s to determine the utility of Tc-99 Tetrofos~ (TFM) imaging in diagnosis of significant coronary artery disease in cc~arison to TI-201 cardiac inmging. 18 patients (pts) with angiographically proven significant CAD were studied by one day ex-rest T~I and ex-rest-re inj. TI-201 imaging. For each study, left ventricle ~ s divided into 20 segnents (segm) and sa~iquanti~tive analysis ~is applied using a 4 point scale. Uptakes~ 2 were accepted as perfusion defects. The degree of uptakes were correlated with the significance of coronary edtery stenesis. 15 pts had nmltivessel d ~ , 8 had 1 and 4 had 2 totally ozcluded coronary arteries (TOCA). 128 of 360 segm. were supplied by II~A(35.5%), 191 were supplied by significantly stenetic arteries (53%) and 41 were normft. In TOI~ group, TFM demonstrated 14 reversible (11%=)and 76 fixed (59%0) defects while 15 segm ~_re reversible (12%) anrl 69 (54%) were fixed in TI-201 study. 15 s % m ~ filled in after KI.

* = p< .05; ** = p<.Ool ;*** = p<.oOOl ,*'***= p<.oo5

Significant difference in the extension of inducible ischemiawas found between group1 and 2 (3.8 _+4.2 vs 1.2 + 2.4;p<.05) as well as between group1 and C group (3.8 + 4.2 vs 1 +_ 0.6;p<.05).Thus VCS enlargement after stress is a common finding in hypertensive pts with LVH probably due to functional subendocardialischemia even in the presenceof normal coronaries.

In conclusion, we suggest that, ~ defects have to be interpreted with caution since wa ob~rved more fixed defects corresponding to myocardial regions supplied by TOCA in T~M imaging when c c ~ e d to TI-201 RI myocardial perfusion study.

1

$88

Abstracts Wednesday morning, April 9, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

84.14

84.12

VASCULAR OR MYOCARDIAL DYSFUNCTION IN MICROVASCULAR ANGINA: THALLIUM AND TECHNETIUM IMAGING COMPARED. M. Kostkiewicz, W. Tracz. Jagiellonian University Collegium Medicum, Institute of Cardiology, Department of Cardiac and Vascular Diseases, Cracow, Poland Patients with arteriographieally normal coronary arteries and exertional angina have per fusion abnormalities on the thallium scanning. It has red to the suggestion, that defects of thallium uptake may reflect myocyte dysfunction. 23 patients with entirely normal coronary angiogral~y, but abnormal post exercise thallium scans (TI'~'), undeLwent exercise perfusion scanning using teelmetium (To~ in) labelled MIBI, a flow marker not taken up into myocardium and functionally comparable to microspheres. Analysis was performed in 3 ways: visually, semiquantatively from polar plots and quantitatively. [ anterior septal inferior ] lateral

8__k4_k_

0_

quant 13 I 3 7 17 3~J~-~O Summary: Presence and site of peffusion defects for stress thallium and technetium perfusion agents show high concordance in patients with microvascular angina, supporting the view that they represent inducible perfusion defects, due by inference to microvascular ~tysfunction.

84,13

W E D N E S D A Y

A M A P R I L

9

Assessment of the rate of change of myocardial uptake under the exercise and resting condition on T c - 9 9 m Tetrofosmin myocardial SPECT N. Kinos hit a,H. $ ugihara, K. Ito, T. Maeda, M. Nakag awa. Kyoto Prefectural University of Medicine, Kyoto, Japan We designed the method to obtain the rate of change of myocardial Tc - 99m - Tetrofosmin (l-F) uptake by exercise, using exercise - rest TF SPECT imaging with a 1 - day protocol. Fifteen normal cases and 20 patients with coronary artery disease (CAD) were studied. A 370 MBq of TF was injected at peak exercise. Initial (TF-1) and delayed (TF-2) exercise SPECT images w e r e acquired 30 rain and 3 hours postinjection. A 740 MBq of TF was reinjected soon after TF-2 acquisition, and rest SPECT images(TF3)were taken 30 min postinjection .Bull's eye plots which was reconstructed by each SPECT image,was divided into 16 segments.Myocardial counts of TF-1,TF-2,TF-3 were calculated from each Bull's eye plot and defined C1,C2 and C3 respectively .Then, the rate of change of myocardial TF uptake of exercise to rest(AMTU : myocardial tetrofosmin uptake)was determined by the following formula. AMTU = [CI×FV(C3-C2)-I]xl00(%) (R: dose ratio) AMTU was 57.8+9.9% in normal cases and roughly correlates maximal heart rate(r=O.60, P<0.05).AMTU in ischemic regions was smaller than that in non-ischemic regions in CAD (>75% coronary stenosis : 20.1+-6.9%, >90% coronary stenosis : 15.1_+ 5.3%, non-ischemic : 36.6+ 7.3%,P<0.01). AMTU may be considered as an index which means the changeof rate of coronary flow to cardiac output at exercise. In conclusion, AMTU is a useful index to evaluate non-invasively coronary flow reserve.

18FDG PET CHARACTERISTICS OF DIFFERENT TYPES OF LEFT VENTRICULAR ANEURYSMS T.Sz(ik, Zs.K6szegi, L.Bajnok, L.Balkay. University Medical School Debrecen, Debrecen, Hungary. The authors examined the F-18-fluoro-deoxy-glucose ('"FDG) uptake of 10 patients (8 men, 2 woman, age: 53.2±9.3 years) with previous myocardial infarction, in lee ventricular segnents corresponding to the lee anterior descending artery (LAD). The anatomical aneurysms associated with a hump on the diastolic contour were differentiated from akinetic or dyskinetic fi.naetional aneurysms by ventriculography. The average ~SFDGuptake of the segments associated with the anatomical aneurysms was 20.8±4.1% as compared to the activity of the normal se~-oments, while corresponding value in functional ones was 37.8+ 14.5% (p=0.0045). A relative activity below 25% in more than one segment occured only in anatomical aneurysms. Assessment of the anterograde flow by coronary angiography in non-occluded LAD patients revealed a higher value in functional aneurysms as compared to anatomical ones (3:~0.71 vs. l±0). Examination of the metabolic and perfusion activities revealed that segments showing mismatch occured more freqently in functional than in anatomical aneurysms (37.5 vs. 21.4%). Conclusions: anatomical aneurysms usually develop in areas with an laFDG activity below 25% and low residual flow. A perfusion-metabolic mismatch is more frequent in cases with functional aneurysms.

84,15 THE ROLE OF SCINTtGRAPHIC LEFT VENTRICULAR AREA IN DIFFERENTIATION OF CAD FROM DCM Hiroaki Abe, Hiroshi Yamabe, Atsushi Yamamoto, Junichi Hanaoka, Takahiro Funakoshi, Mitsuhiro Yokoyama Kobe University School of Medicine, Kobe, JAPAN It is often difficult to distinguish coronary artery disease (CAD) with left ventricular dysfunction but no evidence of previous myocardial infarction from dilated cardiomyopathy (DCM). The aim of this study was to clarify the role of scintigraphic perfusion image in differentiating CAD from DCM Twenty- six patients underwent perfusion SPECT and coronary angiography. Defect score ( DS ) and scintigraphic LV area (LVA) were measured in all patients respectively. CAD group (n=10, EF 33+13%) revealed larger defect score and smaller ventricular area than those of DCM group (n=l 6, EF 28+" 11%, ns vs CAD) ( DS : 17-1-8 in CAD vs 10"1-5 in DCM, p<0.05, LVA : 275~60 in CAD vs 378+'90 in DCM0 p<0,05). We concluded that the ventricular enlargement assessed by scintigraphic LV area as well as defect size is useful for differential diagnosis between CAD end DCM.

Journal of Nuclear Cardiology V o l u m e 4, Number 1, Part 2

Abstracts Wednesday morning, April 9, 1997

$89

84.16

84.18

COMPARISON BETWEEN REST T H A L L I U M 201 AND TECHNETIUM 99M-LABELED T E T R O F O S M I N IMANGING FOR A S S E S S M E N T OF D E F E C T SEVERITY AFTER MYOCARDIAL INFARCTION. V. Bourgeois, J. Lipiecki, B. Citron, D. Scellier, J. Maublant, A. Veyre, J. Ponsonnaille. University of Clermont-Ferrand, FRANCE.

PREDICTION OF FINAL LEFT VENTRICULAR EJECTION FRACTION AFTER PRIMARY PTCA FOR ACUTE MYOCARDIAL INFARCTION: PERFUSION SPECT VERSUS DOBUTAMINEECHOCARDIOGRAPHY. R. Sciagr~t, L. Bolognese, P. Buonamici, S. Sestini, P.F. Fazzini. Nuclear Medicine, University of Florence ; Florence, Italy.

We p r o s p e c t i v e l y compared in a s y m t o m a t i c patients after myocardial infarction (MI), the myocardial uptake of thallium-201 (201TI) at rest w i t h rest t e c h n e t i u m - 9 9 m tetrofosmin (99mTc) uptake in the territory of infarct related artery (IRA-TR), using quantitative single-photon emission c o m p u t e d t o m o g r a p h y (SPECT). At inclusion 15 days after MI, each patient had (i) a contrast ventriculocoronarography (2) 201TI SPECT (3) rest 99mTc SPECT 48 h later. SPECT data were analysed quantitatively (18 sectors/pt). The values of each sector were normalized respectively to a normal 201TI and 99mTc data base, expressed in standard deviation (SD) and average for the IRA-TR. Thirteen patients (59.38±14 years) had completed the overall protocol. In IRA-TR the mean uptake at rest is statisticaly different between 201TI and 99mTc, respectively (SD) : -2.35 ± 3.35 vs -3.61 ± 2.19 (p<0.05). In conclusion: the defect in the IRA-TR is more severe with Tc-99m-Tetrofosmin than 201Thallium SPECT.

The left ventricular ejection fraction (EF) is a main prognostic indicator in acute myocardial infarction (AMI), but early EF may be underestimated because of myocardial stunning in salvaged areas. We tested whether early perfusion imaging and low-dose dobutamine echocardiography (LDD Echo) by detecting stunned myocardium may estimate LVEF outcome in AMI treated with primary PTCA. Within 1 week of successful PTCA (TIMI grade 3), 58 patients underwent Sestamibi SPECT and LDD Echo. Tracer activity (A) was expressed as % of myocardial peak A and wall motion was scored from 1 (normal) to 4 (dyskinesis) using a 16-segment model. Infarct zone (IZ) mean A, baseline and LDD wall motion score index (WMSI) were then calculated. EF was measured early after AMI and at 1-month follow up. Data were evaluated using multiple regression analysis. Early EF was significantly related to IZ baseline WMSI ([~ = -.67, p < 0.00005) and IZ mean A ([3 = ,41, p < 0.0002), but not to IZ LDD WMSI. At l-month, EF was significantly related to IZ mean A (I] = .60, p < 0.000001) and I Z L D D WMSI (13 = -.27, p < 0.01), but not to baseline WMSI. The EF improvement from early to l-month value was significantly related to LDD induced WMSI changes (~ = .34, p < 0.01). These data suggest that in AMI treated with primary PTCA, late EF is more closely related to IZ myocardial perfusion than to LDD WMS], although the LDD-induced WMSI changes may help predicting the EF improvement.

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84.19

99mTc-M{8I UPTAKE AND ~EST GATED-SPET DATA !N iNFARCTED MYOCARD!U11

QUANTIFICATION OF INFARCT SIZE. 99mTc-MIBi SPECT VERSUS PEAK SERLLM CPK COMPARISON WITH ENDSYSTOLIC VOLUME. JA Valcnti, A Martinez, M Castell6n, F Castillo, JA Nu~o de la Rosa. Hospital Virgen de la Arrixaca. Marcia. Spain. The aim of this study was to evaluate two methods of qnantificafion myocardial infarct size and to compare with enzymatic determination of Crcatin Kinase (CPK), and to correlate to the major predictor of survival: cod-systolic volume (ESV) index. Thirty consecutive patiens (24 males), ~ t h a mean age of 57 years (range 36 to 73), was admitted to the Coronary. Unit with diagnosis of acute myocardial infarction of anterior location, without previous myocardial infarCtion. All of them undenvent ~Te-MIBI-SPECT at rest between 5°-?° day, and two mctheds of quantification perfusion defect were obtained. Method A used all transaxial myocardial tomograms and obtained a percentage of infarct size respect to the total left ventricular mass by adding several ROls. Method B used a polar map generated of the short axis tomograms and obtained a percentage of infarct size by only ROt. Both methods used a 55 % threshold of maximal counts because of the results of the nom~al control group (n=10). Peak serum CPK aetivib, and ESV angiographic index was determinated. By method A, mean oi'infaret size was 27 -+ 15 %, and by method B was 25 + 16 (1"=0.88; p<0.001). The mean peak CPK aetivi~- was 2671 +_ 1722 Lq and had a weak correlation with A (r'=0.4g; p<0.007) and B (r=0.46; p<0.01). In relation to ESV index, method A correlated better (r=0.64; p<0.001), than B (r~ 0.58; p<0.001) ai~tdCPK peak (r-~0,49; 15<0.005). lfi stu~a~]ary.,both methods OFquantification, A and B, are comparable to measure acute myocardial inl~ction of location anterior, but there was weak correlation between perfusion defect size and enz3anatie method. In oar group, method A was found the best closely related to prognostic index.

G. Rubini, C. Memmota~, F. Lauriero, D, Rubini, G. Di ~iovine, L. Sorgente', M. Lepera°, P. ~izzon °, A. D'Addabbo. Dept. of Nuclear Medidne and Dept. of Cardiolagy°, 8ari University, iTALY The aim of" this study was to compare the counts variation measured by rest G-SPET in infarcted rnyocardiaI segments to the 99mTc-IIIBI uptake evaluated on rest no-Gated-SPET. We studied 23 Pts (mean age: 62 years) with prwious II1, Rest G-SPET was performed by a singie head gamma-camera (acquisition at 1.5 h afLer injection, llO0 MBq 99mTc-Sestamibi, LEHP.. collimator, orbix 180", 64x64 matrix, :32 steps, 50 seclstep, 8 Frames/tide). No-Gated data was obtained by adding the 8-frame data. The regional analysis (anterior, lateral, inferior and septet waY,) of counts variation between systolic and diastoiic phases was performed on mid-ventricuiar short axis slices. TEE thickening data was obtained by same mid-ventricular section as a mean of five heart cicles. We distinguished the myocardial segments by a MIBI uptake greater or less than 50% of maximum ventricular activity, The first shows always a good kinetic and significant counf, increase, The 18% of myocardial segments with a MIBi uptake less than 50~ also showed a significantcount,increase on GaLed-SPET and residualfunctionto TEE. In conclusion, 6ated-SPET data could be uset'ull to recognize myocardia! segments hypoperfused but with a good function. The 50% PtlBI uptake lreshOd must be considered cautiously to define as infarcted myocardia! segrnent.

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Abstracts Wednesday morning, April 9, 1997

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84.22

DIFFERENT PROGNOSTIC VALUE OF FIXED TL-201 DEFECTS THAT IMPROVE AFTER REINJECTION (Rj) IN P T S W I T H RECENT A N D C H R O N I C M.I. W I T H P R E S E R V E D L.V. FUNCTION.

PROGNOSIS A S S ' E ~ ~ U/fCOldlq,ICKl'~l MYOCARDIAL INFARCI"IO.N:Vd~AT~AS CHA~G]~DIN ~ '~I"HROMBOLY'I'ICI~.A"? G ~/ta, SK Protosido, M Falcidieno, E Casati, C Vecchio. Divisione di Cardiologia, E.O. Ospedali Gallier% Oenova, Italy.

P.L. Pieri, A. Tisselli, M. Pretolani, G. Moscatelli, G. Sarti, C. Mazzotti. "Bufalini" Hospital, Cesena, Italy. To assess the prognostic value of fixed T1 defects (F) that become reversible (R) after Rj (F-->R) we studied 95 pts with recent M.I. (f.u. 8 mo; 24 cardiac events) and 124 pts with chronic M.I. (f.u. 4 yrs; 22 cardiac events) with Stress/Rd/Rj. All pts had a preserved L.V. function. Event free Kaplan-Meier survival curves were compared, in both groups, in pts with and without F-->R. Results: While in recent M.I. the presence of segments showing F-->R was related to a higher incidence of cardiac events (p<0.01), in chronic M.I. such a correlation was not found. conclusions: The presence of F-->R after Rj may have a different prognostic value in pts with recent M.I. vs pts with chronic M.I., all with a preserved L.V. function.

W E D N E S D A Y A M A P R I L 9

Journal of Nuclear Cardiology January/February 1997, Part 2

To evaluate the incidence of cardiac events, after en uncomplicated acute myocardial infarction (AMI) /rested with /hrombolysi% we studied 391 cousecutive patients (l~ts) followed up t~r 3 yesrs: 183 Ireated in the "pre-lhrombolytic era" (1983-85) (gr. A); 208 l ~ treated with thrombolysis in the acute phuse (1991-94) (gr. B). The mmual iacidence of curdiec deeth was 1.5% verses 1.o% ( p ~ ) . The incidence of severe ischemic events ('Ill-IV Cmmdien angina, need for reveaeulariz~ion, reinfarction) was 6% versus 9.9% (p<0.025). The incidence of heart failtare was 1.5% versus 0% (p<0.0I). In gr..4., mortality was predicted by exercise induced dyspnoea (p=0.001), rest end exercise left vealricular ejection fraction (LVEF) (p<0.005), ST segment elevatioa (t ST) in ECGruphic infarction area (1~0.001) a,d late eneurismal evolution (p-~.01). At Cox multiple regression (COX), rite only indipondeatly signifleent variable was exercise LVEF (p< 0.005). In gr. B, mortality was predicted by age (p<0.025), previous AMI (p<0.025), late mleurismal evolution (p<0.025), blood pressure response to exercise (p<0.001), 4'ST (I",<0.00025). At COX, t'ST was file only indipondeatly significaut variable (p=0.05). All the cardiac events were indipendently predicted in gr. A by the presence of both LVEF decrease and #ST (p--~.002); in group B, by t-CPK (p<0.002). Conclusions: Pts treated with itwombolysis show a greater incidence of ischemic events and a lower incidence of heart failure. LV dyffunction is the best predictor of death in the conlrol group, but its

import~ce is decreased in Its heated with lhrombolysis: they liequently suffer ischemic events depending on the prompt reperfasion

intheacutephase.

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84.23

ONE YEAR PREDICTION OF THE PATIENT OUTCOME AFTER A FIRST INFARCTION: VALUE OF THE BLOOD POOL GSPECT O. Demonceau, C. Vanhove, J. De Vuyst, D. Bladt, S. Diericlc~. St Elisabeth Hospital, Zottegem, Belgium.

QUANTIFICATION OF INFARCT SIZE BY 9~Tc-MIBI SPECT. COMPARISON OF TWO METHODS. A Martinez, JA Valenti, R Florenciano, F Mulero, J Galeera, JA Nufio de la Rosa. Hospital Virgen de la Anixaca. Murcia. Spain.

The gated bloodpool tomograp~' (GSPECT) gives the ability, not only to aocurately measure the ejection fraction and the volumes of the 4 cavities, but also to evaluate the extent and the depth of a dyskinesia. We evahuate the place of these parameters in the evaluation of the 1year prognosis of the patient~ medically treated alter a first myocardial inli'~rction. Eight' seven patients underwent during the first 15 days after infarction a GSPECT, an echocardiography, a SPECT at rest with Tc-MIBI and a bicycle elNometric proof Their results as well as the clinical and enzymatic data were analysed. The prediction was made on the outcome of major as well as of global cardiac events during the first year following the infarction. The GSPECT were analysed using a 4D-automatic processor, eventually ton'coted by the experimentator. The best multivariate Cox model to predict the total cardiac events included the standard deviation of the intensity of the contraction of the LV on a pixel base (p= 0.01 ), the presence of diabetes (p= 0.02), the surface of the detect on the RV (p= 0.03), the active flow of the am'icles (p= 0.08) and the depth of the phase abnormality on the LAD ten-itory of the left ventricle (,p=0,08). For the major events, the best predictors were again the standm'd deviation of the intensity of the contraction (p= 0.01 ) and the contractility of the apex of the RV (p= 0.007). ]'he intbrmations coming from the other imaging techniques cannot be satistilctoD' included in the model, due to their weak c,on'elations and/or double use. This stud}, thus emphasises the importance of the asynchreny as well as the 4 cavities analysis for the prognostic of patients medically treated after ird'aretion.

The aim of this study,was to compare two methods in determining infarct size (IS) by quantification of Tc-MIBI-Spect and to correlate them with the usual predictors of sun,ival, left ventficu/ar ejection fraction (LVEF) and left venlrieular end-systolic volume index (ESVI). 27 consecutive patients admitted with a first acute rayocadial infarction (AMI) of anterior location in the first 24 hours of evolution underwent 99mTe-MIBI-SPECTat rest betaveen5th and 7th day, and two methods of quantification perfusion defect were performed. Method A used all trans&xial myocardial tomograrns and obtained a percentageof IS respect to the total left vuntricular mass by, adding several ROls, Method B used a polar map generated of the short axis tomograms and obtained a percentage of IS by only ROL Both methods used 55% threshold of maximal counts aecording to results of the normal control group (n=10). ESVI was obtained from angiographyand LVEF from radionuclide ventricnlograp~,. Mean of IS by method A was 264-14 % and by method B was 24~15 % (r=0.89, p<0.O01). Mean LVEF was 434-11% and ESVI was 474-27ml/m2. Correlation between A and B with LVEF was r= -0.69 (p<0.001) and r= -0.55 (p<0.0OS). Correlation betwecn A and B with ESVI was r-= -0.75 (p<0.001) and r= -0.68 (p
Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday morning, April 9, 1997

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84.26

RISK OF ISCHEMIC EVENI'S Attt.K UNCOMPLICATED TI[RObH3OLYSIS. MYOCARDIALINFARCTIONTREATED~ SK lh-otosido,G M~zotta, M Falcidieno, A C~merini, E. Casati, C Vecchio. Divisione di Cerdiologia,E.O. Ospedali Galliera, Oenova,Italy.

PROGNOSTIC VALUE OF REVERSE REDISTRIBUTION (liaR) ON TL-201 SPECT OF PATIENTS WITH MYOCARDIAL INFARCTION F.Faccio; F.Vigoni; A.Blasco; P.Wagniart; F.Achard. Centre Cardiologique du Nord. Paris. France.

Aim of this investigationwas to identify subgroupsof patients (lqs) at risk of ischemic eventsafler an aneomplicated acute myocardial infarction (AMI) treated with thrombolysis: we evaluated 208 consecutive t~ts (182 males). Mean age was 58+10 years, mean leR ventricularejectionfraction (LVEF) at rest was 50-213%;the follow-up lasted 3.25+2 years. We analyzed: a) severe angina 0R-IV Canadian; 121R) + non fatal A.MI(18 Pt) + one severe, fatal isehemiceverY,b) all the previous ones + necessityof myocardialrevescularization(361R). Results: at univarinted analysis, the following variables revealed a significantassociationwith the end-point a): female gender (p<0.025), ECGrafie site ofAMI (p<0.05), inducible angina (p<0.025) and the time fi'omthe onset ofsimptom to CPK peak valne (t-CPK) (p<0.025). At Cox multipleregression, the only indipeadeatlysignificantvariabile was t-CPK (p<0.05). At univariated analysis, the following variables were associated with the end-point b): inducible angina and ST segraentdepression(p<0.0025,p<0.0025), blood presslfe response to exercise (p<0.025), rest and exercise L ~ (p<0.0025, p<0.005) and the t-CPK(p<0.001). At multiple regression, two variables were indipendently significant:inducible angina and t-CPK (p<0.001, p<0.002). Ischemicevents occured in the territory of the infarctrelated~ artery in 95% of the Pts Conclusions: i~hemic events are predicted hy simple and cheap variables: t-CPK and exercise inducible anginawith lack of additional predicted value of LVEF.

Our objective was to determine the frequency and prognostic value of RR pattern, on TL-201 SPECT restredistribution, of patients (pts) with myocardial infarction (MI), with patency of the infarct-related coronary artery. We selected 44 pts (39 male, 5 female), aged 544-11 with first acute MI, with catheterization whithin 24 h aRer the onset of chest pain. A rest-redistribution TL-201 SPECT was performed within a mean of 3.2±1.7 days post-MI. Quantitative analysis was used. All pts were classified into 3 groups, according to the redistribution pattern: I-RR; IIfixed (F); III-redistribution (RD). The 3 groups were comparable in terms of ejection fraction, extent of CAD and MI size. Mean pts followed up was 14.64-10.1 months. Myocardial revascularization, reinfarction and death were considered as events. The frequency of patterns was 45% for RIL 34% for F, and 20% for RD. Events-free survival was 73%, 53% and 23% for RR, F and RD respectively (p<0.'02 for RR vs RD). Thus, the RR pattern is frequent (45%); and it is associated with a lower cardial events rate.

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84.27

MUL'IIVARIATI~ APPROACH TO RISK STRATIFICATION OF MYOCARDIALINFARCTION~ ' I ' E D wn-H JFHROIVIBOLYSIS. O Mazz.otta,SK th'otosido,M Falcidieno, E Casnti, C Vecehio. Divisione di Cardiologi~ E.O. Ospeduli Gallier~ Genova, Italy.

COMPARISON OF 1-123 BMIPP, Tc-99m MIBI AND TI201 SPECT FOR PREDICTION OF LATE LEFT VENTRICULAR FUNCTION IN ACUTE MYOCARDIAL INFARCTION. Kouichi Sano~ Shigeyuki Nishimura, Kenichi Katoh, Toshiko Ohta, Kimitsu Central Hospital, Kisarazu, Japan.

Aim of this studywas to identifypatients (Pts) at risk of cardiac death or cardiac events tiler an uncomplicatedmyocardial infarcion (AMI) heated with thrombolysis. We evaluated 208 coasecative Pts (182 males) followed up for 3.25+2yeefs. Mean age was 58+10 years. Results: a) 11 ~ died for cardiac reasons and at univariated analysis the following variables were associated with death:previous AMI (F<0.025), late aneurismal evolntion (p<0.025), blood pressure response to exercise(IK0.001), ST segment elevation (! ST) with exercise (p<0.01). At Cox multiple regression (COX), the only independentlysignificantvariablewastST with exercise (p--~.05)A'ST was correlated with anterior infarction (p<0.001, r---0.24),late aneurismal evolution (p
To determine which agent accurately predicts the late left ventricular function in patient with acute myocardial infarction(AMI), We prospectively evaluated 1-123 betamethyliodophenylpentadecanoic acid (BMIPP), Tc-99m MIBI(MIBI) and TI-201(TI) SPECT images in 25 patients. In all cases, the infarct vessel was revascularized by thrombolysis or primary PTCA. These three SPECT imagings were separately performed 15__.6 days after onset. Polar map images were quantitatively compared to normal data bank. Late left ventrieular ejection fraction (EF) was calculated by contrast ventriculography at 4 months. The mean defect sizes (>2SD below the mean count for normal data bank) by early BMIPP, early TI, delayed TI, and early MIBI SPECT were 41%, 31%, 34%, and 35%, respectively. There were the good corrrelation between EF and the defect size by early BM1PP (r=0.79,p<0.0001), early T1 (r=0.73, p=0.0002), delayed TI (r=-0.66,p=0.0017), and MIBI (r=0.69,p=0.0007). In conclusion, BMIPP imaging at subacute phase of AMI is superior to rest MIBI and T1 imaging for prediction of late left ventricular function in patients with successful reperfusion therapy.

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Abstracts Wednesday morning, April 9, 1997

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84.30

Impact of cardiac performance at discharge after AMI on subsequent increase in pulmonary blood volume.

THE SCINTIGRAPHICAL EVALUATION OF THE EFFECT OF PREINFARCTION ANGINA ON THE AMOUNT OF MYOCARDIAL SALVAGE BY REPERFUSION THERAPY. Y. Hashimoto, S. Watanabe, K. Watanabe, I. Murata, K. Hayakawa, S. Tanihata, H. Matsuo, T. Matsubara, Y. Matsuno, H. Oda, Y. Kotoo, H. Ohashi, M. Ishiguro*, Division of Cardiology, Gifu Prefectural Hospital, Hirano General Hospital*, Gifu, Japan

Petersen CL, Appel J, WiinbergN, Haedersdal C. Dept. of ClinicalPhysiology& NuclearMedicine, FrederiksbergHospital, University of Copenhagen, Denmark. AIM: To determine the impact of ventricular performance at discharge after acute myocardial infarction on subsequent increase in pulmonary blood volume. Patients: 14 patients with AMI and subsequent clinical sign of heart failure were included in the study. Patients received medical treatment according to the regimen in the medical department including diuretics, digoxin and ACE-inh. Methods and design: Left and right ventrieular ejection fractions (LVEF & RVEF) and cardiac stroke volume (SV) were determined by radionuclide ventriculography by the countbased principle, with correction for the individual loss of radiation dependent on the depth of left ventricle. Determination of pulmonary blood volume (PBV) was based on cardiac volumes and with measurement of mean pulmonary transit time of first pass bolus in LAO projection. Measurements were performed at discharge and after 6 months. According to measured values of PBV, patients were grouped as "increased PBV" or "not increased PBV" after 6 months. Results: (median values) Baseline cardiac characteristics LVEF: RVEF: Stroke volume (ml): Increased PBV: 0.28 0.52 52 Not increased PBV: 0.30 0.48 96 * (* P<0.05) Conclusion: Based on results of measured pulmonary blood volume, post AMI patients could be categorized as "increased PBV" or "not increased PBV'. Patients who developed increased pulmonary blood volume had a significant lower cardiac stroke volume at discharge of AMI, whereas no difference in left and right ventdcular ejection fraction between the groups was observed.

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Journal of Nuclear Cardiology January/February 1997, Part 2

RENIN PLASMA LEVELS .aND EJECTION FRACTION IN ACUTE MYOCARDIAL INFARCTION WITH AND WITHOUT HEART FAILURE D. Sobid-~aranovi~, I. Ul"o~evid S. Pavlovid, M. Ostojid, N. Kozarevid, Institute of Nuclear Medicine and Institute of Cardiovascular Disease, CCS, Belgrade, YU The purpose of this study was to compare the extent of roninangiotensin system activation (RASA) in pts with first acute myocardial infarction (AMI) without heart failure (HF) and in those with AMI and HF; to assess the relation of extent of RASA to the ejection fraction (EF) as an important parameter of left ventrieular function in AMI. The study included 44 pts with AMI, 33 men and 1i women, mean age 53 years. According to the Killip classification, all pts were divided in 2 groups: Group 1, consisted of 32 pts without symptoms of HF (Killip=l) and Group 2, 12 pts with HF (Killip>2). In both groups Plasma renin activity (PRA) were determined by ILIA method during the first three days of onset of AMI, and on day 7. EF at rest was assessed by radionuelide ventriculography on day 7. Results: Parameters Group 1 Group 2 p PRAin first 72h(nglmlda) 2.54+0.20 [ 3.77±0.28 <0.01 PRA on day7(ng/ml/h) 1.97±0.30 [ 7.09-+0.28 <0.01 EF (%) 48.5-+ 2.5 38.0--±2.3 <0.05 Our results show significantly higher PRA in pts with AMI and HF (Group 2),than in pts without HF (Group l ), especially on day 7. EF was significantly lower in Group 2 than in Group 1. Hyperbolic relation (PRA=0.00054/EF 10) between EF and PRA was t:bund, that implicate more prominent RASA in pts with AMI and EF of 45% and less,

Ba.ckqround. The patients with preinfarction angina tends to have smaller infarct size than that of the patients without preinfarction angina. We retrospectively studied the relation between preinfarction angina and the scintigraphically estimated size of the salvaged myocardium. Method. The 30 patients with preinfarction angina were compared with 23patients without preceding angina. The size of the salvaged myocardium was quantitatively assessed by perfusion defect size of 9S~Tc-tetrofosmin. Result. The %improvement of severity score with preinfarction angina was 71.6 +/- 50.1%, but that without preinfarction angina was 37.8 +/- 28.9%. (p = 0.0019) Conclusion. When a myocardial infarction is preceded by angina, the amount of salvaged myocardium may be smaller than ; the case without preinfarction angina,suggesting the favorable effect of angina as ischemic preconditioning.

84.31 SIMPLE EXERCISE TESTING VERSUS SPECT EXERCISE THALLIUM SCINTIGRAPHY AFTER rrHROMBOLYTIC THERAPY IN ACUTE MYOCARDIAL INFARCTION: CORRELATION WITH ANGIOGRAPHYC DATA SanfmsV, MachadoI, QuelhasI, Sc~a F, FernandesJ; ReisF, Louren~A, GeacraloI,, CorreiaL*, Amorim1",PereiraA, ALmetdaJ Servi~ de Cardiologia,Hospitalda SP da Olivcira,Guimar[les- Portugal *Ser~i~de Medici~aaNuclearda Casade Safld¢da Boavisla,Porto-Portugat Objectives: The value of non invasive methods in risk stratification aRer successful thrombelysis in acute myocardial infarction (AMI) isn't yet validated. The authors evaluated two non-invasivemethods,exercise testing in treadmill (ExT) and exercise thallium SPECT (T1201), in the detection of significant coronary artery disease (CAD) and related there findings with angingraphycdata. Material and methods: Prospective study, evolving 65 patients (P), consecutively admitted in the Coronary Care Unit, between April/95 and January/96, with AMI and treated with thrombelytic therapy. We determined the sensibility and the accuracy of these two methods in the detection of significant CAD, as stablished with coronaryangiogmphy.All tests were performed within the first three weeks after AMI, with no therapy, aRer maximal exercise tests. Results: ExT, when abnormal,had a sensibilityof 48,8% and an accuracyof 32,3%. If the inconclusive tests where considered along with the positive ones, the sensibility was 67,2% and the accuracy xs~s67,7%, T1201 had a sensibility of 98,4% and an accuracy of 95,4%. The statistical difi~ance between the two lasts was significant(Io<0,001 e p< 0,0l respectively). Condusions: In these patients, ExT had a very low ability, to detect significant CAD, even when considered positive the inconclusive tests. Th201 added important information to ExT, and we think it should be porformed in allpatientswhen ExT is normal or inconclusive.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday morning, April 9, 1997

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84.42

SESTAMIBI SCINTIGRAPHY FOR EVALUATION OF TRANSMYOCARDIAL LASER REVASCULARIZATION (TMLR) - PRELIMEqARY RESULTS. T Grtining, J Kropp. S Wiener. WG Franke, B W~itzig, S Schiller. Dept Nuclear Medicine, University of Dresden, Germany

REVASCULARIZATION OF VIABLE MYOCARDIUM F A V O U R A B L Y I N F L U E N C E S L O N G TERM OUTCOME OF PATIENTS WITH END-STAGE ISCHEMIC LEFT VENTRICULAR DYSFUNCTION. A. Gimelli, P. Marzullo. CNR Clinical Physiology, Pisa, Italy on behalf of the VIP Study, Working Group on Nuclear Cardiology and Magnetic Resonance, ESC.

TMLR is a novel treatment in patients with coronary artery disease. It comprises the creation of transmyocardial channels during open heart surgery. To assess TMLR induced perfusion changes gated Tc-99m sestamibi scans were carried out after stress and at rest prior to and 1, 3, 6, and 12 months after treatment. Perfusion of lased segments was compared to that of reference segments.

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We found two different patterns of perfusion changes: a temporarily improved perfusion at I month after TMLR (A) and a steadily declining pcrfusion (B). These results need to be confirmed in a larger number of patients.

Little is know about the effect of coronary revascularization in patients with end-stage left ventrieular dysfunction. To this aim 53 patients (50 male, mean age 60+_7 yrs) with documented coronary artery disease and angiographic ejection fraction <.25 were followed-up for an average of 24-+11 months. Twenty patients were revascularized (group 1) either by angioplasty (11 patients) or by-pass graft (9 patients) and 33 were treated medically (group 2). The 2 groups were matched for age, ejection fraction, number of diseased vessels and number of dyssynergic segments. Both groups showed a similar uptake of Thallium-201 in dyssynergic areas (62~:20 vs 57_+18% of the peak, p=ns for all values). During the follow-up, eventfree survival was 100% in patients of group 1 while 5 patients of group 2 died of cardiac causes and t had non fatal myocardial infarction (event rate 21%). In conclusion, in patients with severe ischemic left ventricular dysfunction, revascularization significantly improved long-term outcome. In these patients, revascularization of viable, dysfunctioning myocardium represents a reliable alternative to orthotopic heart transplantation.

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84.43

DETECTION OF RESTENOSIS AFTER PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY BY DOBUTAMINE MIBI SPECT IMAGING.

AbdouELheudy,MarcelL Geleijnse,Ron T van Domburg, Jos RTC Roelandt, Jan H Cornel, Galal M El-Said, M Mobsen Ibrahim, Medhat El-Reface, Peter R Nierop, Paolo M Fioretti. Thoraxcenter, and Departmentof Nuclear Medicine, Rotterdam,The Netherlands.

LOW-DOSE DOBUTAMINE RADIONUCLIDE ANGIOGRAPHY PREDICTS IMPROVEMENT OF FUNCTION OBSERVED IN VIABt.E MYOCARDIUM AFrER CORONARY REVASCULARIZATION. A. Gimelli, P. Marzullo. CNR Clinical Physiology, Pisa, Italy on behalf of the VIP Study, Working Group on Nuclear Cardiology and Magnetic Resonance, ESC.

Non invasiveevaluationof patients after PTCA is importantfor the detection of restenosis and selection of patients for coronary augiography.The role of dobutamineperfusionscintigraphyin this clinical setting has not been studied. Methods. We studied 40 patients with limited exercise capacity 185 ± 80 days after successful PTCA with high dose dobutamine(up to 40 #g/kg/min) stress test in conjunction with 99m technetium MIBI SPECT. Significant restenosis was defined as >50% luminal diameter stenosis. Results. Reversible perfnsion defects occurred in the distributionof 20 of 29 arteries with and in 4 of 17 arteries without restenosis. The sensitivityof dobutamine MIBI for the detectionof restenosis in arteries with previous PTCA was 69%; CI 56-82, specificity = 76%; CI 64-89 and accuracy = 72%; CI 59-85. Overall sensitivityof MIBI SPECT for the diagnosisof significant coronary stenosis (including arteries without previous PTCA) on patient basis was 79%; C167-92, specificity = 82%; C170-94, and accuracy = 80%; CI 68-92. Sensitivityof MIBI SPECT was higher than electrocardiography(79% vs 38%, p<0.005). Conclusion. DobutamineMIBI SPECT is a useful method for the detectionof restenosisafter PTCA in patients unable to perform an adequate exercise stress testing.

In patients with iscbemic left ventricular dysfunction, little is known about the response of global systolic and diastolic parameters to coronary revascularization. To this aim, we studied 12 patients (1 female, mean age 59_+8 yrs) with previous myocardial infarction and an ejection fraction ( E F ) below .40 by rest/dobutamine (5-10 mcg/Kg/min) radionuclide angiography. An average of 1.8 vessel per patient was successfully revascularized by angioplasty or surgery in 7 and 5 patients, respectively. Follow-up studies were obtained 4 weeks after revascularization. EF at rest was .28_+.9, increased at .36_+.12 during dobutamine (p<.01) and was .37___.10 at follow-up study (p=ns vs dobutamine). Similarly, PFR averaged 2.2+ t .3, 2.9+_1.7 and 3.1+_1.6 EDV/see in the same conditions (p values as EF). End-diastolic volume was reduced by 9% during dobutamine and by 14% at follow-up study. In conclusion, in patients with ischemic left ventricular dysfunction associated to maintained viability, improvement of function can be predicted by low-dose dobutamine radionuclide angiography. The prediction of global parameters allows the preoperative selection of patients in whom a significant improvement of ventricular dynamics is expected.

Regional nwocardial perfusion after TMLR (before=100) GrOup stress Rest lmo. 3 6 12 l m o . I 3 [ 6 112

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101l 911 941 92 1111 97 / 1031 92 771 78/ 731 -

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84.44

84.46

SCINTIGRAPHIC EVALUATION OF PATIENTS AFTER CORONARY ARTERY STENTING IN SINGLE VESSEL DISEASE. Victor Gil, /ultdnio Ventosa, Jogo Calqueiro, Armindo Mesquite, Graqa Caires, Jos6 Baptista, Rieardo Seabra-Gomes Hospital de Santa Cruz. Carnaxide. Portugal.

THALLIUM-201 REST-REDISTRIBUTION SPECT TO PREDICT IMPROVEMENT OF GLOBAL VENTRICULAR FUNCTION AFTER REVASCULARIZATION.

We studied 35 patients (57 + 9 yrs, 28 male) with thallium-201 SPECT 4.7 + 2.5 month after coronary artery stenting in single-vessel disease. Eighteen pts had a previous myocardial infarction and in 20 chronic angina was present. LAD was involved in 20 pt, RCA in 12 pt and LCX in 3 pt. After stenting, chest pain was present in 14 pt and stress testing (dypiridamole in 9, treadmill exercise in 26) was positive in 10 pt. Reversible perfusion defects (RP) in the stent-related myocardial areas were observed in 12 pt. Among patients with chest pain, RP were present in 50%; assymptomatic patients presented RP in 24%. In 17 pt, a recatheterization was performed. SPECT demonstrated a negative predictive value of 100%. Three of the four false positives occurred in pt with previous myocardial i~ffarctionin related area. In conclusion: l-Tomoscintigrapby with thaUium-201 appears to be an excellent tool for the non invasive assessment of coronary stent patency. 2 - The valorization of perfusion defects in areas with previous myocardial infaetion should be done with caution. 3 - Clinical parameters are poor predictors of stent stenosis

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Journal of Nuclear Cardiology January/February 1997, Part 2

Jeroen J Bax, Jan H Cornel*, Frans C Visser**, Paolo M Fioretti#, Abdou Elhendy#, Cees A Visser**. Leiden, *Alkmaar **Amsterdam, #Rotterdam. The Netherlands. Thallium-201 rest-redistribntion (T1 RR) imaging has been used to predict improvement of regional left ventricular (LV) function following coronary revascularization. This study was pertbrmed to evaluate whether TI RR SPECT can predict improvement of global LV function after revasculanzation. Patients (n=31) with contractile dysfunction underwent TI RR SPECT and resting echocardiography before revascularization. The echocardiographic and SPECT images were analyzed using a 13-segment model. Various patterns on TI RR were used as markers of residual viability in dysfunctional segments (1.normal perfusion, 2.mild fixed reduction of TI uptake and 3.significant redistribution). Improvement of global LV function was assessed by echocardiography/radionuclide ventriculography, performed before and 3 months after revascularization. Improvement of LVEF >5% was considered significant. Patients with >3 dysfunctional but viable segments on T1 RR were classified viable. All 8 (t00%) patients with >3 dysfunctional, viable segments improved in LVEF. In contrast, only 4 of 17 (24%) patients with _<3 dysfunctional, viable segments improved in LVEF. In addition, a linear relation existed between the number of dysfunctional, viable segments and the improvement in LVEF (y=l.36*x-l.7, r=0.70). These data suggest that substantial viability (>3 segments) on T1 RR may predict improvement of global LV function after revascularization.

84.45

84.47

CAN DIPYRIDAMOLE THALLIUM-201 SPECT ACCURATELY PREDICT RESTENOSIS IN ASYMPTOMATIC PATIENTS ONE YEAR AFTER SINGLE VESSEL PTCA? B'Palagi'A'Bell°ni*'A'C°l°mb°*'S'B°cc°lari'AP°lese*'R'Picozzi Nuclear Medicine Laburator.'-Hospital of Saronno;*Dix4sion of Cardiology Hospital "L.Sacco" -Milan- Italy

IMPLICATION OF TC-P9M TETROFOSMIN REVERSE REDISTRIBUTION IN REPERFUSION MYOCARDIUM. T. Kajiya, Y. Yasaka, A. Takarada, T. Hayashi, A. Yoshida, M, Mori, T.Itagaki, H. Kurogane, Y. Yoshida. Himeji Cardiovascular Center, Himeji, Japan

Background:foUowing percutaneous translunfinal angioplasty(PTCA) thallium stress imaging can predict restenosis in asymptomatic patients with fairly good sensiti~4ty,but low specificity. However,the source of such a low specificity has not yet been studied. Methods: 58 consecutive patients(mean age 57+9 years) who remained asymptomatic aider a successful PTCA of single vessel coronary artery disease(CAD) were studied by dipytidamole thallium201 SPECT(DIP-SPECT) as well as by coronary angiography 11±3 months after revascularization.Prior to PTCA, of 58 patients, 27(47%0) had had an acute myocardial infaretion(AMI) in the supply region of the dilated vessel(Group A),while 31(53%) did not(Group B). Results: Group A and Group B did not differ significantly with respect to both pre-PTCA and post-PTCA stenoses. Residual ischemia as detected by DIP-SPECT was observed in 18(67%) of 27 Group A patients,but in only 7(23%) of 31 Group B patients(jy=0.001g).The accuracy of DIP-SPECT for predicting asymptomatic restenosis is summarized as follows: Patients Sensitivity Specifici~- PPV NPV Accuracy Overall(n=5g) 73% 64% 32% 91% 66% Group A(n=27) 78% 39% 39% 78% 52% Group B(n=31 ) 50% 79% 14% 96% 77% Conclusions:DIP-SPECT predicts asymptomatic restenosis with lower specificity in those patients who,ptior to PTCA, had had an: AMI in the supply region of the dilated vessel.

The uptake of Tc-99m tetrofosmin (TF) into heart mitochondria is related to plasma and mitochondrial membrane potential in a energy dependent manner. We tested that myocardial TF kinetics can be used as a marker of mitochondrial metabolic status. We studied 54 patients (pts) with acute myocardial infarction treated by direct PTCA without restenosis. In 22 pts, TF SPECT belbre reperfusion was done to determine myocardium at risk. Before discharge, TF was administered at rest, and SPECT was obtained at 15 min. (initial) and 3 hours (delayed) SPECT images were divided and graded from normal (0) to background (3). On TF initial image that indicates myocardial flow, 21pts (group A) revealed prcserved [low (grade0, 1) and 33 pts(group B) revealed intermediate or severe ischemia (grade 2,3). The amount of myocardial salvage (salvage/risk area) of group A was greater than that of group B (78% vs. 22% p<0. 05). On delayed image that indicates mitochondria[ membrane fnnction, new defect, defect worsening and/or extension occurred more frequently in group A compared to in group B (95% vs. 45%, p<0.05). In conclusion, viable myocardium alter ischemia-reperfusion shows prolonged disturbance in TF retention that may indicate disturbed mitochondrial membrane integrity and abnormal metabolic status.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday morning, April 9, 1997

84.50

84.48 MYOCARDIAL PERFUSION AFTER REVASCLrLARISATION: IMMEDIATE AND LATER EVALUATION A.Teresifiska, B.Szumilak, E.Gosiewska, Z.Juraszyfiski, Z.Slipko, A.D~bski National Institute of Cardinlogy, Warsaw, Poland In our research we study the myocardial perfusion history, by means of stress-rest Tc99m-MIBI SPECT, in pts submitted to cardiac mvaseularisation (re',,). Perfu~ion studies are perfomaed 3 times: before rex' (we-rev), as soon as exercise is allowed a:Rer rev (postearly), and a few months later (post-late). The aim of the research is to optimize : (1) patient selection for rev (viability evaluation), and (2) time point for post-rev perfusion evaluatio~ This is a continuation 0fthe work presented preliminary in [1]. In 6010ts with pre-rev SPECT, CABG was performed in 39 pts (27 with MI) and PTCA in 21 pts (I6 with MI). Post-early SPECT was performed 10(3-28) d alter PTCA or 33 (13-65) d otter CABG. Post-late SPECT was performed g7 (60-11 g) d after PTCA or 120(g%174)d ~ CABG. SPECT studies were assessed qualitatively mad quantitatively by 3 experiancod observers. In comparisen to pre-rev study: in 15 of 18 pts with persistent defects only, no perfusion improvement was detected in post-rev (early nor late) studies; in 40 oi"42 patients with tramieat perfusion defects, perfusion improvement in underperfused areas was detected in post-rev studies. In 40 (67%) pts, the same perfuslon pattern was found in post-e.a-rly and post-late studies. In 12 (20%) pts, perfusion improvement between post-early and postulate studies was observed (but in l0 of these 12 pts qualitative results in post-late study were close to post-early results). In other 8 (13%) pts, perfusion deterioration in post-late study was obselrvedin comparison to post-early study, In conclusion: (1) In pts with persistent perfusinn defects in pre-rev study, post-rev peffvsien improvement is very rare (15118=83% of studied cases) and in pts with lransiant perfusion defects perfusion improvement is very high (40/42=95% of eases) what proves high usefulness of stress-rest Tc-99m-MIBI SPECT in viability evaluation. (2) Results of post--early and post-late studies are comparable in most pts (50/60=g3% o f studied pts) - what proves high usefulness of stress-rest Te-99m-MIBI SPECT in very early evaluation of revaseularisation effectiveness (during post-rev hospitalisation). [lJ Teresihska A, et aL Tc-99m-M[BI SPECT perfus¢on evaluation immediately after cardiac revaseularisation and three months later [Abstract]. Eur J Nucl Med 1995; 22: 797,

EFFECT OF REPERFUSION THERAPY BY PYP/TL DUAL SPECT AND BMIPP IN ANTERIOR ACUTE MYOCARDIAL INFARCTION Y.Nakazawa, H.Suyama, T.Kaneda, S.Hirai, Y.Goto, K.Inoue, N.Nakamura, K.Masui, Y.Isoda, H.Kato. Matsue Red Cross Hospital, Matsue, Japan Aim of the study was to assess the effects of primary PTCA using PYP/TI and BMIPP SPECT in anterior MI. Nineteen patients underwent PYP/TI, BMIPP SPECT and LVG during the acute phase, and TI SPECT and LVG 1 and 3 me after reperfusion. Each SPECT study was scored using a 18 segment, 0 (normal)-4(no uptake) point system. Salvage score was calculated as; (BMIPP score - Tt score)/BMIPP score in acute phase. During acute phase, BMIPP, TI and salvage score was 14.1, 6.2 and 0.60, respectively. TI score 1 and 3 me after reperfusion was 6.8, 4.9. Salvage score had a significant negative correlation with peak CK, TI score 1 and 3 me after reperfusion. Salvage score was higher in the group without PYP accumulation. We suggest that the salvage score provide a useful marker of myocardial viability and salvage in the acute stage of MI.

84.49

84.51

Incidence of i~hemia after balloon angioplasty versus stenting assessed by sestamibi-Tc99m.

RELATIONOF SEPTALUPTAKEOF 99mTc-SestaMIBIIN LB.B.B. TO SEPUM-TO-LATERALWALL SYSTOLICPHASE-DIFFERENCE ON GATEDPLANARMYOCARDIALPERFUSIONSCINTIGRAPHY D.R.Jangid ;EscortsHeart Inst.& Res. Cntr., New Delhi-25. INDIA

Osvaldo Masoli, Daniel Cragnolino, Carlos Rapallo, Gustavo Calderon, Alejandro Meretta, Nestor Perez Balifio, Horacio Talione, Nestor Blanco. Institute Cradiovascular de Buenos Aires, Argentina. Background: The use of stenting probably reduce the incidence of reestenosis compared with balloon angioplasty., but is not well known which is the incidence of myocardial ischemia with each procedure. We analyzed the incidence of ischemia in the first control post procedure in 57 patients enrolled prospectively and consecutively, 19 patients were treated by. balloon, 29 patients by stenting and 9 patients by balloon in one artery and stenting in other. We performed stress perfusion SPECT imaging with sestamibi-Tc99m 2 days protocol. We classified the results as ischemic and non-ischemic and it was correlated with the involved arte~. There were 28 arteries with balloon angioplasty (Group A) and 38 Stenting arteries (Group B). Ag~ Da~s~er Rest rka 9aess Saess Weddeod

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SBP

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55.7+7 60+_26 74+12 126+14 1405:18 177+_21 664_+191

C_ao~B 56.8+8 83.-k52 71:t:8 128-+16 138~.14 179+_22 671:1:141 * pns ** p = .0529 (by Xi square) Ischemic response in the sanle treated artery territory, were: in Group A: 11/28 (39.3%) and in Group B: 15/38 (39.5%), pns. Only 2 patients in each group developed angina during the stress test. Conclusion: There were no differences between both procedures in the incidence of ischemia in their first control perfusion studies.

Although left bundle branch block (LBBB) is known to reduce septal myocardial uptake (SMU) of 99mTc-SestaMIBI, yet the relation of septal-to-lateralwall (S-L) myocardial uptake rafio (Ur) to $-L phase difference (AC(s.i);using Fourier analysis of gated planar myocardialperfusionscintigraphy)has not been studiedpreviously. A regressionrelation between Ur and A~(s.i) (n=18open dots in the Figure) has been obtained; Ur=-0.009A~(s.I)_+0.88.Fromthis relation it is possibleto differentiate reduced SMU due to LBBBfrom that due to myocardialinfarction/hibernation (MI/MH). An S-L Ur which is 2 S.D. (2c) less than the mean (m) trend expected from LBBB would suggest MI/MH. 9 patients with normal and 16 patients with hemodynamically significant of left anterior descendingcoronaryartery disease(LAD-CAD)were studied. LBBB patients with normal 1.00, , .17=Normals coronary artedes were clustered . ~_ Io= LBBB around Ur=0.8 and AC(s.i)=20°. However, 13 patients (out of 16: 81.25%) with angiographically proved LAD-CADhad their S-L Ur well below 2~ of the LBBB range. In the remaining 3 o.oo-" " patients low SMU was 'falsely' 20 Aes4 70 i ascribed to LBBB.

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84.53

W E D N E S D A Y A M A P R I L 9

Journal of Nuclear Cardiology January/February 1997, Part 2

84.55

QUANTITATION OF THALLIUM LUNG UPTAKE & WASHOUT KINETICS USING DYNAMIC SPECT. B.K. McCandless and J.A. Cooper, Albany Medical College, Albany, NY, USA

USEFULNESS OF THALLIUM 201 WASHOUT AND UPTAKE IN PATIENTS WITH SYNDROME X FMulem,M.I.Castell6n,J.A. Valeutt,J.A.Ruiz-Ros,J.A.Nufiede ta Rosa.Hospital Virgen de la Arrixaca, Mureia, Spain

Pulmonary thallium-201 uptake is an important finding during myocardial perfusion. Following stress, thallium clears rapidly from the lungs but the physiology of thallium washout kinetics and its clinical relevance remains unclear. Furthermore SPECT imaging makes assessment of lung uptake and its clearance more difficult. We developed a method to quantitate the rate of lung thallium washout during SPECT imaging. Dynamic SPECT was performed using three 180° acquisition performed in rapid sequence using a standard single head camera. Acquisitions alternated between clockwise and counter-clockwise camera rotations. Regions of interest were drawn around the lungs in the projections of the first acquisition and copied onto the projections of the second and third acquisitions. Lung washout was calculated from an exponential fit of the ratios of lung activity from the first/second acquisitions and second/third acquisitions. Patients with severe CAD or LV dysfunction had washout rates that were 2 to 3 times that patients without CAD whereas patients with one or two vessel disease had intermediate rates of washout despite having lung:heart ratios that were less than 0.50.

Syndrome X defines a group of patients who present typical angina pccturis,positive exercise test and normal corona~ arteriogram.Iu studies with ThaUium 201 in these patients,incidence of appearance of reversible deflects showing a reduction in blood flow reserve is less than 20%.The purpose of this study is to asses the result of Thallium scan and washout in subjects with S)~adrome X.24 patients salected from those undergoing diagnostic angiography for .typical angina who had normal artefiograms were studied with Thallium 201 SPET to evaluate uptake and washout.Washout was calculated appl)~ng the formula stress uptake-redistribution uptake / stress uptake. Thallitml defects were found in 3/24 and washout defects in 22/24. There is a statistically significative reduction ( p<0,0.5 ) in thallium uptake and washout in patients with syndrome X compared to a control group. Thallimn scans Syndrome X Controls Mean Stress counts 83.72 111.99 Mean Redistribution counts 86.2 108.13 Washout -3.11 3.44 Conclusion the visual analysis of Tallium-201 slices is of limited value in patients with syndrome X.Analysis of Thallium 201 washout provides additional information.

84.54

84.56

WEIGHT-BASED DOSING OF Tc-99m SESTAMIBI FOR STRESS MYOCARDIAL TOMOGRAPHY: A REGIMEN FOR MORE EQUITABLE IMAGE QUALITY. G.A.Hurwitz, G.J.Morrissey, S.M.Quirk and P.Slomka. Victoria Hospital, London, Canada.

ARTERIAL CONCENTRATION OF TC-99m-SESTAMIBI DURING THE EARLY PHASE AFTER VENOUS BOLUS INJECTION.

Standardizing count statistics on image acquisitions might improve the results of myocardial tomography (MT). We retrospectively evaluated a protocol in which Tc-99m sestamibi was targeted for injection in doses (MBq/Kg body weight) of (i) 12 for stress MT, (ii) 3 for rest MT prior to same-day stress, and (iii) 5 for separate-day rest studies. Peak myocardial activity (ACT) was outlined on immediate post-stress anterior oblique planar images (IMM) and on corresponding tomo-acquisitions at 1 hour post-stress (DEL) in a series of 1600 consecutive MT studies; stress doses were within 20% of target in 94% &cases. ACT was higher on same-day studies (by 14% for IMM, and 18% for DEL, p<0.0001) compared to separate-day studies. On the latter (n=720), ACT showed 2- to 3-fold interindividual variation, but was independent of body weight. Variability for a fixed-dose (1000MBq) protocol in the same population was calculated to be greater (by 44% for IMM, 34% for DEL), with inverse relationships to weight (r>0.6). These data suggest that the uniformity of MT images in a clinical setting could be enhanced by weight-based dosing.

The aim of this study was to characterize the early phase of the sestamibi time-activity curve. Bolus injection of 700 MBq Tc-99msestamibi was performed in 11 patients with one-vessel disease during PTCA. Blood samples of 1 ml were collected from the leR femoral artery every 5 sec. during the first 5 minutes post injection. The time-activity curve for Tc-99m-sestamibi is shown:

N.P.R. Sand, L. Thuesen, J.P. Bagger, C. FI~, T.T. Nielsen, M. Rehling. Departments of Nuclear Medicine and Cardiology. Skejby University Hospital, Denmark.

Time-ectivity curve for Tc-99m-sestamibi in arterial blood

50% 0% 0

1

2

3

4

5

Time after injection, min

The relative amount of sestamibi available for uptake was calculated as the area under the curve (AUC) by numeric integration and by exponential extrapolation. The pmcentual part of the AUC from injection to 1, 2, 3, 4 and 5 min. in relation to the whole AUC from injection to imaging were as follows: 55%, 76%, 85%, 90% and 93%. Evaluation of myocardial perfusion during brief episodes of ischaemia by sestamibi-SPECT requires careful consideration of the timing of injection in relation to the length of the ischaemic stimulus.

Journal of Nuclear Cardiology Volume 4, Number l, Part 2

Abstracts Wednesday morning, April 9, 1997

84.57

84.59

QUANTIFICATION OF REGIONAL LUNG DENSITY

Y.FUKUMOTO M.SUZUKI, Mite Kyoudou General Hospital, Mite, Japan.

AND BLOOD VOLUME W I T H T O M O G R A P H I C AND BLOOD POOL IMAGING. Luis I. Araujo, Ronald Kern, Joseph Maffei, Abass Alvai, Joseph R. McClellan. University of Pennsylvania, Philadelphia, P A Extravascular lung water was previously assessed with PET and transmission images (T). Regional lung density may also be deten-nined during SPECT with T and attenuation correction. SPECT T and blood volume images (BP) were obtained in 10 patients without known cardiopulmonary disease. Studies were acquired with a Picker 3000 X P scanner with Gad 153 (T) source. Total lung density (TLD) and blood volume (BVol) were obtained by analyzing ROI in the anterior and posterior lung segments in T and BP. The T and BP were normalized and extravascular density (EVD) was calculated by subtracting B Vol from TLD. Differences were assessed with the Student T test. R e s u l ts: TLD B Vol EVD Postlung 0.43+0.15" 0.20-L-_0.07 + 0 . 2 3 + 0 . ! 2 # Ant lung 0.34+0.12 0.13+0.04 0.21+0.10 Po/A ratio 1.36+0.17 1.61+0.50 1.09+0.40 *p=0.02; +p=0.0003; #p=NS C o n c l u s i o n : SPECT transmission and blood pool images allows quantification of regional lung density and noninvasive assessment of lung water.

REST-PRECEDED 1-HOUR METHOD.

Rest-prsceded exemise-stressed myocardial SPECT with 99mTc-tetrofosmlo (99mTc) was investigated for the purpose of completing the entire examination in less than 1 hour. Method: The following 3 parameters were examined. (1) Dose ratio : A balloon, which was inserted into the inferior wall of a head phantom, was used to represent a defect during exemise. (2) Acquisition time : Scans of the myocardial region of a phantom were obtained by changing the acquisition time per view. (3) Timing of the start of imaging : Count ratios d organs surrounding 1he heart in the planar scans were examined, Results: (1) The site of ~ balloon was unclear at the 3 limes higher dose, but appeared as a definite defect at the 4-fold Ngher dose, (2) The circumferential profile curve obtained at an estimated dose of 222MBq and an acquisition time of 20 seconds per view during rest was almost equal to that obtained at an estimated dose of 740MBq and an acquisition time of 30 seconds. {3) During rest, the liver/hsert count ratio {L/H) reached a maximum after 10 minutes. During exercise, L/H reached a maximum after 20 minutes. The protocol of the real-preceded l-heur method was as follows : Resting scans were obtained starting 15 minutes after intravenous administration of 99mTc at 222MBq during rest (20 seconds per view), After completion of scanning at rest, exercise was stalted immediately, 99mTc B88MBq was administered, and then exemise-alressed scans were obtained (5 seconds per view). When SPECT was performed by the rest-preceded 1-hour method in 75 patients undergoing CAG, the sensitivity was 79% in the LAD, 64% in the LCX, and 82% in the RCA, and the specificity was 89%, 94% and 79%, respectively. Conclusion: The rest-preceded 1-hour method of myocardial SPECT reduced the duration of the patient's restriction, while preserving a conventlorlal method.

84.58

84.60

Tc-99mfrl-201 M'YOCARDIAL COUNT RATES : INFLUENCE OF' PATIENT HEIGHT / WEIGHT AND TYPE OF STRESS M.K. O'Connor, E. Bothun, R.J. Gibbons, Mayo Clinic, Rochester, MN, USA.

DELETERIOUS EFFECT OF CORONARY BYPASS SURGERY ON RIGHT VENTRICULAR FUNCTION S Woldman, G McCurrach, W Martin, I Hutton, Department of Medical Cardiology, Glasgow Royal Infirmary.

This study examined the variability in myocardial activity with 99mTC sestamibi (S) and 2°lTl (T) SPECT imaging, as a function of patient anthropometric data and type of stress. Methods : SPECT acquisitions were performed in 249 patients (155 S, 84 T). Normal myocardium • was identified in 3 short axis tomographic slices between the base and mid-ventricle by excluding all myocardial counts below an 85% threshold. Data were normalized to a collimator sensitivity of 300 cts / min/uCi, corrected for decay and expressed as counts per pixel per unit activity injected (ct/pix/mCi). Results : For rest S studies, the average myocardial count density was 31.4+11.0 ct/pix/mCi. This showed no significant increase with pharmacologic stress (29.6+10.0 ct/pix/mCi), but increased significantly (P < 0.005) to 42.4__+15.2with exercise. T studies averaged 94.1+31.9 cffpix/mCi with exercise and 112.5+53.0 with pharmacological stress (P=NS). Delayed studies (1 mCi reinjection) averaged 61+23.5 ct/pix/mCi. For S studies and stress T studies in males, there was an inverse correlation (R =0.7 and 0.5) between myocardial count density and patient weight. No correlation was found for T studies in females. Conclusions : Knowledge of rite mean values of myocardial activity as a function of administered dose may be useful in the optimization of rapid imaging procedures for 99mTcbased perfusion agents. The gain obtained from the significantly higher injected dose of S (15-30 mCi) compared to T (3 mCi), is partly offset by the smaller absolute uptake in the myocardium. Marked inter-patient variability in the count density of both agents in normal myocardium is only weakly correlated with body size.

This study was a detailed investigation of right ventricular (RV) and left ventricular (LV) function in ninety three patients undergoing routine coronary artery bypass grafting. All patients were studied approximately one week prior, then 6-9 weeks and nine months post surgery by equilibrium radionuclide ventriculography. LV ejection fraction (LVEF) and RV ejection fraction (RVEF) were calculated in all studies using a single, manual, region of interest method. Overall there was no change in LV function: mean LV function was 33% (_+I0) pre-operatively, 34% (_+13) at 6-9 weeks and 33% (_+13) at 9 months after the procedure. However there was a significant fall in RV function from a mean of 32% (__.8) to 27% (_+7) at 6 weeks and 26% (+7) at nine months (p<0.001 for the change in RV function at 6 weeks and nine months). Thirty patients (32%) showed a deterioration in RVEF of 10% or more at nine months post surgery. This finding was not related to pre-operative LV function, total bypass time or cross clamp time. In summary there is no change in LV function for the population undergoing coronary bypass surgery. RV function deteriorates significantly following myocardial revascularisation surgery. This requires further intensive investigation.

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Abstracts Wednesday morning, April 9, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

86.1

86.3

THE RELATIONSHIP BETWEEN RESOURCE USE AND OUTCOME IN STABLE ANGINA PATIENTS. Leslee J. Shaw, Ami E. Iskandrian, Jack Heo, Mark I. Travin, Gary V. Heller, Duke University, Durham, NC

ECONOMICSOF MYOCARDIALPERFUSIONIMAGING- EMPIRESTUDY SR Underwood, B Godman, S Salyani,J Ogle, U Sechtem, PJ Ell National Heart & Lung Institute, Imperial College, London, UK

CONCLUSION. Post-test cost and resource use may be appropriately guided by evidence of hypoperfusion on stress peffusion imaging.

We have audited 50 patients newly presenting to each of 8 hospitalsfor the diagnosis or exclusion of CAD. The hospitals were regular users or non-users of MPI with one of each in 4 countries (F, D, l, UK). Patientswere followed 2 years after presentation in order to assessclinical outcome. Pre- and post test probabilities of CAD were computed for tests and diagnostic strategies defined were I: Ex-ECG/angio, 2: Ex-ECG/MPI/angio, 3: MPl/angio, 4 anglo. Primary outcome measures were the cost and accuracy of diagnosis, the cost of subsequent management, and the clinical outcome. Mean diagnostic costs per patient were: Strategy I £333,2 £339,3 £288,4 £975 (P<0.00 I). Mean diagnostic cost in the MPI user centres was £373 and in the non-users £519 (P <0.001). Mean probability of the presence of CAD when the final diagnosis was positive/negative were: Strategy I 0.89/0.22, 2 0.91/0.1 I, 3 0.95/0.12, 4 0.97/0.05 (P<0.01 ). Thus quality of diagnosis for the scintigraphic strategies (2 and 3) was higher than strategy I and almost equal to the angiographic strategy (4). Prognostic power at diagnosis was higher (P=0.001) and normal coronary angiography rate was lower (P=0.0 I) in the scintigraphic centres and strategies. We conclude that diagnostic strategies routinely using MPI are cheaper and at least equally effective. Further analysiswill allow the influence of MPI on clinical outcome and the influence of local pricing policies to be assessed

86.2

86.4

EUROPEAN NUCLEAR CARDIOLOGY DATABASE TRIAL 1: MYOCARDIALPERFUSIONSTUDIESWITH 99mTc-MIBI. M.H.Bourguignon (F), R.Giubbini(I), E.Busemann Sokole (NL), PR.Franken (13), A.Ai-Saadi (U.K.), MTBenoit (B), O.Zoccarato (t), B.E.Jones(U.K), J.Kuikka(SF), M.P.Larroek(B), MTh.Pakbiers(NL), &Palmer(S), YRicard(E), G.Schultz(D), J.Verdenel (F), B.Hesse (DK).

ACUTE MYOCARDIAL PERFUSION IMAGING REDUCED LENGTH OF CARDIAC WORK-UP M.D. Duca, A.W. Ahtberg, G.M Cyr, A. Russell, and G.V. Heller. Hartford Hospital, Hartford, CT, USA

The complex interrelationship between resource use and cardiac outcome has not been elucidated. We compm'ed diagnostic catheterization_<90 days (Cath) to the extent of ischemia on stress perfusion imaging (by X2) in 2,613 stable angina patients. The % of patients with 0-3 ischemic peffusion areas (figure) ranged from 68-3%, yearly cardiac death=0.4-3%. Cath rates ranged 23-57% for 0-3 ischemic areas (p<0.001). Diagnostic yield (2.75% stenosis) was highly correlated with the extent of ischemia (r=+0.75, p<0.00I) as was cost. With >1 area,cost= $156, 843. eo

Number of I¢,chemte PeCfu~on A r e s

CardJa~ ~a~osUe ~ Cath=t,=rcato l n Yiald

70

~I =~ 5° 6OI

20

o

W E D N E S D A Y A M A P R I L 9

o

1

2

3

The ENCD project was developed to promote quality assurance of Nuclear Cardiology in Europe. Aims of this study were the evaluation of the effecfiveness of 'lnterfile 3.3' for file exchange, the assessment of variability between centres and of the diagnostic accuracy of 99mTcSestamibi SPECT interpretation for CAD diagnosis throughout Europe.Transaxial slices of 30 stress-rest Sestamibi perfusion studies were distributed to 18 participants recruited from 10 Counlries. Each center was asked to process the data and to evaluate the perfusion in the3 main vascular territories by a 5 point score (normal, probably normal, equivocal, probably abnormal, abnormal). 6 different software packages from 5 manufactures were used. The readers were totally blinded to patient history, sex and body size. Data could be read by 7/18 centres. Among these the evaluation of nega~ity vs positMty (scores 1&2 vs scores 4&5) for Sestamibi SPECT by insfitufion was quite homogeneous (max. disagreement=20%). Sensi~ity and specificity for CAD detection in the 3 main vascular territories in the 7 centreswere 90.'/_7%and 84+9%, respectively. Thus only few centres were able to read Interfile 3.3 diskettes; among these high homogeneity of interpretation and diagnostic accuracy was observed. Efforts w$ be made to provide an easier exchange of data and to promote ENCD lrials throughout Europe.

Acute myocardial perfllsion imaging (MPI) during chest pain correlates well with stress MPI, but its impact upon cost and len~h &cardiac work-up (LCW) is not known. Thus, 33 patients admitted with a moderate or high probability of myocardial ischemia were randomized to usual care or acute Tc-99m sestamibi SPECT imaging during or within 2 hours of chest pain. Acute image results were immediately reported to the physician who managed the subsequent work-up. LCW and associated hospital charges were compared between the 2 groups. n Acute MPI

17

LCW days/pt 2.0 + 1.2 tJ

No MPI

16

3.2 + 1~7

Pts in ICU 5

Charges $/pt 3555 + 1396

2

3467 + ! 879

Up = 0.02 vs no MPI C o n c l u s i o n : Acute MPI significantly reduced the LCW by 1.2 days in patients with at least moderate probability of myocardial ischemia. In addition, despite more ICU admissions in that group, there was no significant increase in charges with acute MPI.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday morning, April 9, 1997

86.5

87.2

~PECT IN ASYMPTOM ATIC PATIENF S: IN~ENTAL PROGNOSTIC VALUE AND RISK STRATIFICATION. Rory Hacl-m~vitch, Druid S. Ben'nm, Leslee J. Sha% Hosen Kia, Ishac C o h ~ John Friedrrm. Gmtge A. Dimxmck Cedas -Sinai Medial Center,, LA, CA, USA

SIGNIFICANCE OF CAVITY DILATATION VERSUS ELEVATED LUNG HEART RATIO AFTER DIPYR1DAMOLE SPECT THALLIUM Christopher L. Hansen, David Travis Temple University Hospital, Philadelphia, PA

Patients (pts) who ae asymptormticbut have rruk~le risk factors are often referred to SPFCT, but the hcrarent al prognostic value of 5t~ECThas yet to be defined inthis popuhtbrk Thus, we evaluated 2502 pts (71% male, Risk Factors 2.0, ag~ 64)who underwera stress sestarNbi ~ E L ~ (1945 e~ercise,481 adenosine) ard had no cardiac symptoms at rest c~ w ~ e~rdse SPECT was visually scored ushg20 segn~-Is on a 5 point s ~ e (0=nomaal,4=no uptake). The strn of the scores of the stress segnmts was calculated for eazh patient (summed stress scorg SSS).Pts were folbwed up for arrean of 22 months for hard events [HE, cardiac death (40),myocardial iffarct b n (32); ov~.ll rate 3,0%] and 76 pts with early revasmlafization (<60 days) were emhdad from prog~sis malysis (3.0%). Coxp mportional ~ r d s maly sis revealed that after ac~usthagfor fikehhoodofCAD, history of CAD, md type of stress used, SSS added significantinfomaaion (~: 19 to 46, p <0.0001). (N) Conc. Stress SPECT yields incremental p rognostic valueand permits risk stratiticatbn inpts without symptorm with both exercise~:1 adenosine stress.

We have shown that Cavity dilatation (CD) and an elevated lung/hem ratio (LH) rarely occur together after exercise and have different clinical con'elates implying different pathophysiologic etiologies. To study their implications after dipyridamole (D), we identified 771 consecutive patients (Pts) (53% female mean age 65+11 years) undergoing D with SPECT thallium without severe motion artifact or dose infiltration. Eleven percent of the Pts demonstrated LH alone, 21% had CD alone and 3% had both. There no significant correlation between LH and CD (r=0.03). LH was abnormal more frequently in males than CD (64% vs. 48% p=0.02) and in patients with a history of heart disease (78% vs. 46% p<0.0001), especially history of CHF (34% vs. 12% p<0.0001) or history of MI (25% vs. 10%, p= 0.003). Pts with CD had borderline greater average ST segment depression (0.3 vs. 0.2 mm; p=0.056) and borderline more positive EKGs (13% vs. 5%, p=0.057) despite having smaller thallium defect size (15% vs 26%, p < 0.0001) and lower severity scores (p < 0.000I) on thallium. We conclude that with D, LH and CD reflect different pathophysiologic events. Pts with LH are more likely to have a history of heart disease, especially MI and CHF and more severe coronary disease as reflected by defects on thallium.

87.1

87.3

THE PROGNOSTIC ROLE OF NORMAL THALLIUM MYOCARDIAL IMAGING IN ASYMPTOMATIC PATIENTS WITH ABNORMAL EXERCISE STRESS TEST. G.Carini, G.Labanti, G.Di Pasquale, S.Urbinati, C.Corbdli, N.Monetti, G.Pinelli. Div. of Cardiology, Bellaria Hospital, Bologna, Italy. Exercise stress test (EST) has a high prevalence of false positive results and therefore a low predictive value in pts without angina. The aim was to assess tile incremental prognostic role of a normal exercise TI-201 myocardial imaging (TMI) in pts with asymptomatic abnom~al EST. I37 consecutive pts (98M, 39F), mean age 53±8 yrs, without history of heart disease or abnormal resting ECG were enrolled and followed-up for 6.4 yrs (range 3-13 yrs). Indications for EST were: awpical chest pain in 56, check-up in 52, sport practice in 29. All pts had a maximal symptom-limited EST. EST was discontinued for fatigue in 129 (94%) cases and for ST-segment depression >_3mm in 8 (6%). Exercise TMI was normal in all pts. During the follow-up, no subject died for cardiac causes. 9 pts had a non fatal cardiac event (l%/yr): a non fatal myocardial infarction in 4 cases, unstable angina in 3 and stable angina in 2. Three pts had a non-cardiac death. In conclusion, in apparently healthy pts with a positive asymptomatic EST, a normal TMI identifies subjects with a very low risk of future coronary events. In these pts coronary angiography should not be indicated.

PROGNOSIS OF PATIENTS WITH ABNORMAL TREADMILLS AND NORMAL SPECT PERFUSION. J. Milavetz, T. Miller, D. Hodge, R. Gibbons. Mayo Clinic, Rochester, MN, USA. Clinical guidelines recommend that patients with highrisk exercise tests (Duke score) undergo cardiac catheterization. The management of patients with intermediate-risk treadmill scores is less clear. Our hypothesis was that a normal SPECT perfusion scan would be associated with a favorable prognosis for patients with intermediate or high-risk treadmill scores. Prior to January, 1994, 1388 patients with intermediate (n=1369) or high-risk (n=19) treadmill scores had normal or near normal exercise SPECT perfusion scans. Followup was 93.5% complete (median 4.7 yrs).There was no association between treadmill score and survival (p>0.5). Results:

Yearsll

13

I

$99

8 I

Survival 99% 97% 95% 89% Patients with high or intermediate-risk exercise test results, but with a normal or near normal myocardial perfusion scan, have a favorable prognosis. A larger multicenter trial to confirm these results is underway.

S 100

Abstracts Wednesday morning, April 9, 1997

87.4

88.1

DOBUTAMINE 201 -THALLIUM SPECT FOR THEi ASSESSMENT OF PERI-INFARCTION AND REMOTE ISCHEMIA IN PATIENTS WITH LEFr VENTRICULAR DYSFUNCTION LATE ~WER MYOCARDIAL INFARCTION. Abdou Elhendy, Jan H Cornel, Jos RTC Roelandt, Ron T van Domburg, Galal M El-Said, Medhat El-Reface, M Mohsen Ibrahim, Paolo M Fioretti. Thoraxcenter, Rotterdam, The Netherlands.

INFLUENCE OF PROLONGED EXERCISE ON M Y O C A R D I A L DISTRIBUTION OF MIBG. M.Estorch, A.Flotats, R. Serra, A. Lizarraga, LI.Bern~, A.Catafau, C,Mari, I.Carri6. Hospital Sam Pau. Barcelona, Spain.

Background. Dobntamine 201-TI SPECT is an accurate method for the diagnosis of coronary artery disease in patients (pts) without previous myocardial infarction (MI). However, its diagnostic value after MI has not been established. Methods. Dobutamine (up to 40 #g/kg/min) stress-reinjectiou 201-T1 SPECT was performed in 71 symptomatic pts with left ventricular dysfunction > 3 months after MI. Ischemia was defined as reversible perfusion detects (RPD). Results. Significant coronary stenosis (>50% diameter stenosis) was detected in all pts. Sensitivity of reversible RPD for the diagnosis of coronary stenosis was 80% in all pts, 70% in l-vessel and 82 % in multivessel disease. Sensitivity for infarct-related artery stenosis was 71% and specificity = 83 %. Those for remote stenosis were 74% and 80% respectively. The severity of fixed perfusion abnormalities derived quantitatively was significantly lower in true positive versus false negative studies in the LCX and R.CA (p<0.01) but not in the LAD territories. Conclusion. dobutamine T1 SPECT is a useful method for the diagnosis of coronary stenosis on basis of RPD late after MI. The severity of fixed perfusion abnormalities influences the occurrence of peri-infarction ischemia only in the LCX and RCA territories probably due to a smaller myocardial mass compared to LAD territories.

W E D N E S D A Y A M A P R I L

Journal of Nuclear Cardiology January/February 1997, Part 2

To assess the influence of prolonged exercise in cardiac sympathetic innervation, nine healthy ultramarathon male runners (age 34+ 11 years) were studied after a four hours race and at baseline with MIBG. After injection of 185 MBq of 123I-MIBG, the athletes were running during four hours, covering 455:8 Kin. Planar and SPECT images of the thorax were acquired at the end of race. Two weelcs later, basal studies were perfi)rmed. A heart to mediastinum ratio (HMR) was calculated to quantity M1BG uptake. Plasmatic m)repinephrine (NE)concentration was measured before and after the race. Basal MIBG studies showed normal myocardial tracer uptake. and HMR was 1.84 + . 16. After the 4-hour race, MIBG studies showed decreased and heterogeneous myocardial tracer uptake, and HMR was 1.70_+.18 (p<0.005). The distance covered correlated with the percentage of decrease of HMR after the race (r=.91, p<0.001). Plasmatic NE at rest was 142+68 pg/ml and after the race was 156+49 pg/ml (p=NS). We conclude that myocardial M1BG uptake is decreased by proh)nged exercise. Intensity of exercise, as measured by distance covered, correlates with the percentage of decrease of MIBG. Prolonged exercise, as sustained sympathetic stimulus, may altere myocardial distribution of MIBG.

87.5

88.2

PROGNOSTIC SIGNIFICANCE OF DOBUTAMINEATROPINE TECHNETIUM-99M IMAGING IN PATIENTS WITH CHEST PAIN LATE AFTER Q-WAVE MYOCARDIAL INFARCTION. M.L. Geleijnse, IL Rambaldi, A. Elhendy, R.T. van Domburg, A. EM. Reijs, D. Pnldermans, P.M. Fioretti. Thoraxcenter, Rotterdam, The Netherlands.

....i-MIBG MYOCARDIAL SCiNTIGRAPHY IN SYNDROME X (S;'0 A. Giordano, G. Lanza*, M.L Calcagni, G. Meduri, A. Fe', C. Pristipino*, C. Trani', R. Franceschir, i**, M. Massaro, L. Troncone and A. Maseri*. Depts of Nuclear Medicine and *Cardiology, Catholic Univ Rome, **Sor[n Biomedica, italy.

Aim of the study. To assess the prognostic value of dobutamineatropine stress technetium-99m perfusion imaging (DAST) in patients with chest pain late after Q-wave myocardial infarction. Methods. Ninety-four patients (mean age 60 years, 68 men) with fixed perfusion defects and chest pain late after Q-wave myocardial infarction underwent DAST and were followed-up for 22 J: 13 months. Outcome events were hard cardiac events (cardiac death or nonfatal myocardial infarction) and any cardiac event (hard events or revascularization). Analysed scintigraphic variables were the extent of fixed perfusion defects and the presence of reversible perfusion defects. Additionally, these latter defects were subdivided into infarct-zone and remote defects. Results. Sixleea patients (17%) had hard cardiac events, 27 patients (29%) had any event. Multivariate models demonstrated that of the clinical and stress test variables only the extent of fixed perfusion defects (OR 3.7, 95% CI I. 1-13.3) and the presence of infarct-zone reversible perfusion defects (OR 4.4, 95% CI 1.3-15.2) had independent predictive value for hard cardiac events. A history of! typical angina (OR 3.0, 95% CI 1.1-8.3) and the presence of reversible perfusion defects (OR 3.3, 95% CI 1.3-8.2) had independent predictive value for any' cardiac event. Conclusions. Both the extent of fixed perfusion defects and the presence of (infarct-zone) reversible perfusion defects at DAST! provide useful prognostic infornmtion in patients with chest pain late after Q-wave myocardial infarction.

in order to assess myocardial [;euroadrenergic function in SX, 12 pts with anginai pain, exercise induced ST depression, normal CORO, and 12 control subjects matched for sex and age, were submitted to planar and SPET myocardial scintigraphy with high specific activity -~-MIBG (100mC~,mg by Sorin Biomedica, Italy). The pts also underwent stress/redist. ~°lT[ SPET. The following results were obtained: mean MIBG heartfmediastinum (H/M) ratio was 1.67 =~.*n56 in SX pts, 2.'12 _+0.35 in control subjects (p=0.026); 7112 pts showed regional uptake defects at SPET; the segments constantly involved were antero-septal, an[ero-basaJ and in[ero-septai (in 7,7 pts). An highly significant correlation was found between the HIM ratio and a SPET regional uptake index (r= 0.98, p<0.00i). 2°~Ti SPET showed reversible defects in 6/i2 pts with global and or regional MiBG abnormalities. In ai! pts lung and salivary glands MfBG uptake was normal. Reproducibility of H/M ratio and of regional uptake index was high in 7 pts who repeated MIBG study after 5 -~* months (r= 0.96, p= 0.001 and r= 0.99, p<0.001, respectively). In conclusion: global and regional myocardial abnorma{ities of neuroadrenergic function are dernonstrated in SX. This finding may be heipfut in clarifying the pa[hephysiology of this "elusive disease".

Journal of Nuclear Cardiology Volume 4, Number l, Part 2

Abstracts Wednesday morning, April 9, 1997

S i01

88.3

88.5

TOTAL DEFECT OF METAIODOBENZYLGUANIDINE (MIBG) IMAGING ON HEART IN PARKINSON'S DISEASE (PD) T. Serita, A. Satoh, M.Tanigawa, M. Seto, S. Sere, M. Tsujihafa, K. Yano. Nagasaki Kita Hospital, Nagasaki, Japan

DELAYED LOCAL DEPOLARISATION AND REPOLARIZATION IN POSTINFARCTION PATIENTS CAUSED BY IMPAIRMENT OF SYMPATHETIC INNERVATION G. Schmidt, P. Barthel, I. Matsunari, R. Schneider, M. Schwaiger, A. Sch6mig. Deutsches Herzzentrum and 1. Med. Klinik, Technische Universit~t M0nchen, Germany.

This study was conducted 1) to evaluate sympathetic cardiac innervation using MIBG imaging in PD, which frequently shows autonomic dysfunction, 2) to examine the relation between the clinical severity of PD rated on the Hoehn-Yahr scale (HY) and abnormalities of MIBG imaging. Uptake of MIBG was measured in 35 PD patients and 29 age-matched controls including patients with cerebral infarction, angina pectoris and neuro-degenerative diseases. Although normal MIBG uptake was observed in PD patients with HY stage1, PD with stage3-5 revealed a total defect of visual MIBG imaging on heart area. Wide variations of MIBG uptake were shown in PD with stage2. Quantitative measurements of MIBG uptake assessed by the radioactivity ratio o! cardiac tissue to mediastinal tissue (H/M) in early imaging was associated with the clinical severity of PD (control; 2.0-Z_03, stage1; 2.0+0.1, stage2; 1.6+0.4, stage3-5; 1.3+0.1). These differences were more intensified in delayed imaging. Washout rate was significantly higher in stage3-5 than in controls and stage1 (0.45+0.06 vs 0.31+0.09 and 0.31+0.08, p<0.0001). In conclusion, homogeneous impairment of sympathetic cardiac innervation was observed in PD patients and this abnormality was associated with the clinical severity of PD, indicating that MIBG imaging of heart is useful not only for the diagnosis but also for the evaluation of severity of PD.

Regional cardiac denervation was defined scintigraphicaily by mismatch between 201TI and 1231-MIBG defect. The goal of this study was to determine whether there is a correlation between mismatch size and electrophysiologic abnormalities in post-MI patients. Methods: 67 consecutive patients who survived the coronaryphase of acute myocardial infarction were included. 2°1TI and 1231-MIBG images were measured in the 2rid week after infarction, using a threshold of 50% of peak counts based on a semiquantitative polar map approach. QT interval, QTc and spatial QT-dispersion were derived from the resting ECG. The frequency of ventricutar premature complexes (VPC's), couplets, salvos and heart rate variability measures were quantified in the Holter ECG. Terminal LAS, terminal RMS and QRS width were measured in the signal averaging ECG. Results: The 201TI[1231-MIBG mismatch size was positively cor~with QTc (p<0.01) and negatively correlated with the terminal RMS signal (p<0.01). There was no significant correlation of the mismatch size with the number of VPC's, couplets and salvos, heart rate variability measures, terminal LAS, QRS width, non-correlated QT and spatial QT dispersion. Conclusion: Lower terminal RMS signals and longer QTc are correlated with the size of 201TI and 1231-MIBG mismatch. These findings suggest relatively slow depolarisation and repolarisation processes within the denervated but viable myocardium, which could contribute to the genesis of late potentials.

88.4

89.1

IS "['HERE A CRITICAL LEVEL IN CARDIAC SYMPATHET[C NERVE DYSFUNCTION ASSESSED BY METAIODOBENZYLGUANIDINE TO PREDICT PATIENT PROGNOSIS. T. Nakata, K. Miyamoto, H. Sasa~, A. Dot, H. Ogata, K. Tsuchihashi, K. Shinmmoto. Sapporo Medical University, Sapl)~m~, Japan.

ESTIMATION OF LEFr VENTRICULAR ELECTION FRACTION (ED BY GATED T c - 9 9 m MIBI SPECT (GSPECT): COMPARISON OF EF AFFER EXERCISE AND AFTER DIPYRIDAMOLE (DPD).

Although cardiac sympathetic nerve function is impaired in patients with cardiac disorders, the prognostic implicatkm has not been established. To determine cardiac sympathetic nerve function level with a predictive prognostic value, 1-123metaiodobenzylguankliue, MIBG, imaging was perthrmed in 414 cardiac patients. Myocardial MIBG uptake was quantified as a heart-to-mediastinum t-arid, H/M, using early and late scans then patients were followed up for 22 months. Cardiac dimensions and functions were evaluated by echocardiography and radionuclidc ventriculography. During followup, 36 cardiac, including 23 due to heart lhilure and 8 to sudden cardiac death, and 17 non-cardiac deaths were observed. Of 15 parameters, age, presence of myocardial infarctiou, late H/M, and NYHA functi(mal class were selected as an independent predictor by Cox-Hazard model but LV ejection fraction, dimension, or early I I/M was not. Late H/M of 1.74 or less, age of mnre than 61) years, presence of myocardial infarction, and NYIIA functional classes 3/4 strongly indicated a poor prognosis and late I[/M was a most powerful predictor ; relative risks were 14.tl5 vs 1.05 vs 2.84 vs 2.12, respectively. Thus, cardiac sympathetic nerve dysfunction assessed by MIBG ilnaging can contribute to assessing cardiac patient prognosis and cardiac MIBG uptake as late H/M of 1.74 or less may be a critical level to determine the probability of poor patient survival due to heart failure or sudden cardiac death.

A. t)'krle, 13. I,fischer, M. Fleisch, S. Lou~_ _ns~J.A.lO'nser lnselspjlal, Unjvcrsi~.of Berne, CH-3010 ~rnv, Switzerland

The a i m o~ this study w a s to compare the rust-stress EF(S-EF) and the rest £F(R-ED assessed b~r GSPECT using (i)exer.cise stress(Ex) a n d (ii)DPD. W e performed a 2-da~ stress/rest protocol in 375 p ts. The EF was obtained by GSPECT pe~rformed 30 nfin. atter stress MIBI-inj. [.266 pts after Ex, I 0 9 pts after DPD (0.84 mg/k_S)] a n d on the tollo',~ing day, 60 min; after MIBI-inj. at rest. 'tlle £F determination was p e r t o r m e a using 3DPerfusion/Motion M a p TM Picker Soflw.are. The pts were divided in 4 groups: A= n o r m a l stress a n d rest scin.tig r a m s without m yocardml infarction (MI); B = p t s > 3 m o n t h s after MI with a fixed defect without revers.ibility; C=pts alter MI with both a fixea aeieet a n n reyersibility~ D = p t s with evidence of stress/rest reversibility without MI. Within D, the DPD lots were subdivided: pts with a n d without ECG evidence of isc'hemia. Of the 375 pts, contrast left ventriculography (CV() w a s performed in 5 7 within 2 weeks of the scinti~rap Lic study. The correlation coefficient CVG-EF vs. S-EF was 0.8"I CVG-EF vs. R-EF 0.87. The results (EF in%) are tabulated: DIPYRIDAMOLE (.=109) IEXErCiSE (n=266) G oup, A B C, D

n 125 57 56 28

S-EF 61--.4 45±11 47 ± 9 56±7

R-EF p 59±4 <0.05: 48±10 n,s, 51 ± 8 <0,05 60±5 <0,05 I D (ECG neg,) D (ECG pus.)

n 50 18 21 20 13 7

S-EF 58±7 41±12 40 ± 11 53±5 55 ± 6 50 ± 4

R-EF 59±6 40±14 44 ± 12 55±6 55 ± 7 54 ± 5

p n.s. n.s. <0.05 n.s. n.s. <0,05

The S-EF is not a l w a ' s the same as t~ R-EF. In ,,normal" ~ts S-EF after Ex was sig~ ificantly higher t h a n R-EF, b u t after E 'D no sig.n.if.icant difference was~found. In g r o u p s Wi.'th stress/rest reversibility, the S-EF atter Lx was si~,nincantly lower t h a n R-EF, but affer DPD only in pts with ECG evidence of iscnemia. The estimation of EF with GSPE.CF reveals good correlation with CVG, a l t h o u g h it systematically underestamates the Lr.

S102

Abstracts Wednesday morning, April 9, 1997

89.2

89.4

LEFT VENTRICULAR VOLUMES AND EIECTION FRACTION FROM GATED SPECT MYOCARDIAL PERFUSION STUDIES. H Everaert, PR Franken, P Flamen, A Momen, A Bossuyt. Free University of Brus~ls (AZ VUB), Belgium.

IA N E W M E T H O D F O R Q U A N T I F I C A T I O N OF REGIONAL AND TEMPORAL WALL THICKENING ON GATED SPECT Michael Y.H. Shen, Robert Fetterman, W e n d y Brunt, Eduardo Paixao, Albert J. Sinusas, Barry L. Zaret, Frans J. Th. Wackers, Yale University, N e w Haven, CT, USA.

Two basically different algorithms both operating in 3-D space, one dependent on surface detection developped at Cedars Sinai' (CS) and another, dependent on statistical parameters devclopped at Stanford University (SU), were compared in the same patients to assess the left ventricular volumes (LVV) and the left ventricle ejection fraction (LVEF) fi'om gated-SPECT myocardial peffusion images. Perfusion SPECT images gated in 8 time bins were recorded in 40 patients with CAD 60 rain after the injection of 740 MBq 99mTcTetrotbsmin at rest. The LVEF-values were validated against planar gated 99mTc blood pool studies (RNA). The software success-rates were 95% (38/411 pts) for CS and 100% Ibr SU. Linear regression analysis showed an excellent correlation between the LVV obtained by CS and SU (r=0.98). The LVEF obtained by RNA ranged from 12 to 88%. Agreement between CS and SU and agreement between both methods and RNA were excellent (CS= 0.9 SU + 6.5, r= 0.93; CS= 0.9 RNA + 4.0, r= 0.93 and SU= 0.9 RNA + 0.9, r= 0.94). Bland-Airman plots showed that differences between LVEFs were similar over the complete range of LVEF values and were not affected by the ped'usion defect severity. We conclude that both CS and SU algorithms can be used to assess LVV and LVEF from gated SPECT myocardial perfusion images, even in patients with severe perfusion defects. Although the CSmethod failed in 5% of the cases, the !najor advantages of this algorithm are its fully automatic character and short processing time.

W E D N E S D A Y A M A P R I L

Journal of Nuclear Cardiology January/February 1997, Part 2

G a t e d S P E C T (GSPECT) imaging has been used to e n h a n c e diagnostic accuracy of SPECT by assessing regional contraction. Analysis of G S P E C T is generally performed visually, and m a y lack accuracy. W e developed a new method to quantify regional wall thickening (WT) from G S P E C T . Sector W T index (I) is c o m p u t e d as (ES-ED)/ED from maximal circumferential profiles for 72 sectors in short axis slices. W T I intra- and interobserver reproducibility was r=0.99 and r=0.97, respectively. W T temporal delay (WTD) was defined as percent of sectors with a temporal delay in sector maximal counts relative to global ES. The method was tested in 20 normal (NL) pts with low likelihood of C A D and 20 pts with MI. First pass L V E F was 6 2 + 6 % in NLs, and 48_+t2% in MI pts. M e a n G S P E C T W T I in NLs was 47+6%. In 19/20 M I pts, WTI was below lower limit of NL (mean-2SD) in MI regions. Minimal W T I was 11_+9% (p<0.001 vs. NL). W T occurred simultaneously in all 72 sectors in 19/20 NLs. In contrast, in 15/20 M I pts temporal h o m o g e n e i t y was disturbed in 14 + 1 2 % of sectors. Thus, this new method allows reproducible quantification o f regional and temporal W T on G S P E C T . MI pts are not only distinguished fi'om NLs by decreased WTI, but also by delayed temporal W T in pert-infarct area.

89.3

89.5

99mTc-SESTAM1BI GATED SPECT PERFUSION STUDY tN DETECTION OF CORONARY ARTERY DISEASE IN WOMEN: COMPARISON BETWEEN THE END-DIASTOLIC IMAGES AND THE SUMMED IMAGES. R. Taillefer, E.G. DePuey, J.E. Udelson, G.A. Belier, L. Giering, C. Benjamin, A. Gagamn, HrteI-Dieu de Montrral, Montrral, Canada. End-diastolic images (EDI) can be easily derived fi'om 99mTe-Sestamibi gated SPECT perfusion study (SGS). This may reduce the effect of myocardial wall thickening during systole and potentially improve the sensitMty especially in patients with small hearts. This prospective study was conducted ha 53 female patients in order to compare the diagnostic accuracy of EDI to lhat of the sunamed images (SI) of SGS.Fifty-tba'ee patients with suspected CAD, scheduled tbr coronmT angiography were evaluated with SGS. Treadmill stress testing was used in 28 patients and dipyridamole in the remaining 25 patients. A two-day protocol was used as follo~: stres,s test with 25-30 mCi of M1Bl and a rest study performed 24 hours later with the same dose. Sixteen ti'ames/cardiac cycle were acquhed lbr both rest and stress studies. Tlu-ee end-diastolic frames were used lbr EDI mad all the 16 fi'ames were stulamed for SI. SI and EDI were interpreted by 3 blinded observers (consensus reading) during two distinct sessions. Coronm3' angiogn'aphyshowed > 50% stenoses in 38 patients and was normal in 15 patients. The sensitivity was 73.7% (28/38) and 84.2% (32/38) respectively for SI and EDI. Three out of 4 patients with CAD not detected by SI but seen wish EDI were considered to have relatively small hearts. The specificity was 86.7% (13/15) and 80~0% (12/15) for SI and EDI respectively. On a total of 90l segmenk% 106 ischemie defects were detected by SI and 173 by EDI (p = 0.001). The segmental agreement between the two teclmiques was 88.6% (798/901 segments). In conclusion, EDI showed more ischemic defects and a slightly better sensitivity than SI in detectiou of coronm 3, artcl3, disease in women, especially in patients with small hearts.

REGIONAL THICKENING ON GATED TOMOGRAPHY FOR DETECTION OF REVERSIBLE ISCHEMIA IN SEVERE STRESS PERFUSION DEFECTS: A COMPARISON WITH RESTING AND 24-HOUR REDISTRIBUTION THALLIUM IMAGES. K. A. Williams, C. M. Schneider. The University of Chicago, Chicago, IL, USA.

Myocardial thickening, a potential index of defect reversibility (REV), was assessed in segments with severe hypoperfnsion on stress Te-99m-sestamibi (MIBI) images by an increase in regional count density during systole on gated SPECT (GSPECT). Methods: GSPECT polar maps were generated for each of 8 fi'ames accluired after stress MIBI injection in 47 patients with coronary artery disease and at least one severe perfusion defect (PD) on summed SPECT images. Using Fourier amplitude (AMP) images, regional m) ocardial systolic thickening was assessed by quantifying the stress MIBI activity in regions of interest which contained _<50% of maximal regional activity, and comparing this with activity in the corresponding AMP,. resting thallium-201 (REST) and 24-hour redistribution (24HR) images. Results: In 53 severe stress PDs, there was a significant correlation between AMP and the regional tracer activity at REST, stress and 24HR (r = 0.46, 0.39 and 0.30, p=0.0002, 0.0027 and 0.0232, respectively), showing the correlation ofperfusion and thickening. Using a cut-off of 10% tmprovement on either REST or 24HR images, 42 PD's were reversible (40 by 24HR vs. only 18 by REST, p = 0.0002) and 11 nonreversible PD's. U s i n g the 24HR defect REV as the standard, AMP criteria of>20% normal thickening had only 38% sensitivity and 54% specificity (ROC curve area = 0.56 ± 0.08). Conclusions: 24HR images delineate a greater degree of PD REV in severe stress MIBI defects than do REST thalliunl-201 images, most likely due to detection of hyp,operfused, hibernating non-contractile mvocardium. In severe PD s regional thickening by GSPECT MIBI'AMP images is an insensitive index o f P D REV, when compared with 24HR amages.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday morning, April 9, 1997

S 103

90.1

90.3

POLAR MAP DISPLAY OF %SYSTOLIC WALL THICKENING IN GATED ~r>'I'c-SESTAMIBI SPECT: IMPROVEDACCURACY BY MINIMIZING ERROR DUE TO CARDIAC TWIST Y. Ishida, S. Kawano, Y. Hirose, N. Yoshimura, Y. Shimotsu, H. Nonogi, National Cardiovascular Center, Osaka, Japan

EVALUATION OF LEFT VENTRICULAR FUNCTION BY RESTGATEDSTRESSTc-99m SESTAMIBIMYOCARDIALPEP,FUSION SPECT IMAGING IN PATIENTS WITH SEVERE CORONARY ARTERY DISEASE. M. Mazzanti, G. Cianci, A. Baldinelli*, V. Viozzi* S. Tonnarelli*. Lancisi Heart Hospital Ancona and Villa Serena Jesi*, Italy.

For generating the polar map of count-based %systolic wall thickening (%SWT) in gated ~Tc-sestamibi SPECT, the disorientation of the target region from diastole to systole due to cardiac twist should be corrected. For the correction, we developed a new soft-ware program moving the position of the end-systolic (ES) circumferential profile curve to correspond the pattern with the end-diastolic (ED) curve in each short-axis slice by utilizing a cross correlation method. Also, considering that %SWT normalizedfor ED countsin each pixel overestimates contractile function in regions with reduced perfusion, we normalized %SWT in each pixel for mean ES counts in all the pixels. We used this new method to analyze the functional recovery after reperfusion therapy in 12 patients with acute myocardial infarction. When wall motion (WM) abnormalities in LVG and %SWT were compared in the corresponding segments, %SWT showed a significant decrease with WM abnormalities progressing (p<0.01): 29:t6% in normokinesis, 22+7% i n hypokinesis and 13±6% in akinesis. In 22 segments with the improvement of WM from 1 to 3 month after the onset, %SWT showed a significant increase from 18±7% to 23±8%, but in 16 segments without the improvement it remained the same (17.d:9% to 17:1:8%). Thus, this new method improved accuracy in calculating %SWT on the polar map and contributed to the estimation of changes in regional contractile function.

Gatedacquisitionis usuallyperformedwiththe post-stress study, beginning approximately 15 to 30 minutes after the injection of 99mTc-sestamibi (MIBI) at peak stress. Thus the post-stress gated SPECT acquisition provides information about stress perfusion and resting ventrieular function. Inclusionof resting gated tomographicimages in the evaluation of stress sestamibi pert'usion defects appears to significantly improve specificityfor detectionof coronary artery disease(CAD)by the evidence ofassociation of wall motionabnormalities(WMA) and ischemia. In this study, 167 patients (pts) with known CAD, without history of previous miocardialinfarction,underwent rest-gated(R-g)stress MIBI myocardial perfusion studies (SMP).The post-stressacquisitionswere performed 25 minutes (25') and 60 minutes (60') after the injection of MIBI at peak stress. The myocardium was divided in 20 segments and scored on a 5point scale lbr pedhsion score (S) of 0 to 4 with 0 being normal and 4 absent uptake and for wall motion score (WMS) of -I to 3 being -I dyskineticand 3 normal.We used the sum orS (SSS)to assess the severity ofCAD and the sum ofWM S (SWMS)to assess the extent ofmyocardium with WMA. Resting globalleft ventricularejection traction (LVEF) was also calculated for both 25' and 60' R-g. 70 patients (57%) showed SSS of 12+1.7 and post stress WMA at 25' R-g analysis (SWMS 38+6.1 ). At 60' R-g, 66 of 70 revealed significantreduction of WMA with SWMS of 55_3.1 (p<0,01). This probably reflect significant amount of post-stress stunned myocardium. Furthermore, the LVEF at 25' R-g was 0.45+0.12 and 0.56+_0.11 at 60' R-g (p<0,0t). The findings strongly support the use of R-g at 1 hour after the injection of M1BIat peak stress in patients with large amount of myocardiuln at risk to avoid errors in the evaluation of rest left ventricular function.

90.2

90.4

VALIDATION OF A NOVEL, AUTOMATIC, COUNTSQUANTITATING LEFI' BASED METHOD OF VENTRICULAR SYSTOLIC FUNCTION USING GATED SPECT Tc-99m SESTAMIBI PERFUSION IMAGES D.A. Calnon, R.J. Kastner, W.H. Smith, G.A. Belier, D.D. Watson, University of Virginia, Charlottesville, U.S.A.

THE PREVALENCE OF NON-UNWORM SOFT TISSUE ATTENUATION IN MYOCARDIAL SPECT PERFUSION IMAGING AND THE IMPACT OF GATED SPECT Thomas A. Holly, Michele A. Parker, Robert C. Hendel. Northwestern Univ. Medical School, Chicago, Illinois

During systolic contraction, the myocardium thickens and the endocardial surface moves inward, although detection of this endocardial motion relies on the relatively limited spatial resolution of the SPECT system. On ECG-gated perfusion images, maximal myocardial counts are related to instantaneous wall thickness via the partial volume effect, providing a quantifiable measure of systolic wall thickening independent of edge-detection. A counts-based method of automatically computing the left ventricular ejection fraction (LVEF) from regional thickening in 14 myocardial segments was correlated with equilibrium radionuclide angiography (RNA) in 22 patients. The correlation between tests was excellent (slope=0.98, R=0.93). In 5 other patients, repeated LVEF measures on separate days were highly reproducible, with a root-mean-square deviation of 4%. Thus, this new counts-based method of measuring global left ventricular systolic function on ECG-gated SPECT sestamibi perfusion images correlates well with RNA, is reproducible, and has theoretical advantages over edge-detection methods.

In order to determine the frequency in which attenuation (A) artifacts (art) are suspected, we examined 1496 consecutive pts (58% men) over a 7 mo period. Review of studies included a cine display of rotating planar projections. Diaphragmatic (D) A was suspected in 44% of studies in men and 13% in women; breast (B) A was suspected in 2 men. However, B tissue was possibly/probably related to art production in 8% and 45% of women, respectively. B A artifacts were highly correlated to body size, as those with suspected art had higher body weight ratios (1.44 vs. 1.26; p<0.0001). No such relationship was noted in men with D A. Gated SPECT imaging was performed in 437 patients and did not increase the frequency of B art interpretation. However, recognition of D A art increased from 29% to 35% in men with the use of a gated acquisition (p<0.05). In conclusion, soft tissue A is frequently suspected as causing art in a general patient population. Additional recognition of this D A art in men was achieved with the use of gated SPECT. These data e m p h a s i z e the importance of gated SPECT and rotating projection data to enhance recognition of nonuniform A.

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Abstracts Wednesday morning, April 9, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

90.7

90.5 TRANSMISSION SCANNING IN OBESE PATIENTS

FOR

ATTENUATION

CORRECTION

E Prvulovich, AHR Lonn, JB Bomanji, PH Jarfitt, PJ Ell University College London Medical School, UK For attenuation correction (AC) of SPET myocardial perfusion images an accurate attenuation map is required. This study investigates whether prolonged transmission scamaing is required in obese compared to slim patients. Methods Over 200 days 29 obese patients (mean body mass index 34 kg/m2 (range 25-48 kg/m2) underwent sequential emission/transmission imaging for AC using an L-shaped dual headed camera (GE Optima) fitted with two 18.5 GBq ~3Gd (half-life 242 days) scanning line sources. Transmission data were acquired for 5 seconds/view (protocol for slim patients) and for 10 seconds/view (s/w~). Images (AC5 and AC 10) were reconstructed using both sets of transmission data in turn. Tracer distribution was qualitatively assessed by two observers blinded to study type. Polar plots were generated for each data set and count density assessed in 17 myocardial segments. For assessment of transmission scan count density regions of interest were selected over the heart. Results No significant differences in tracer distribution were seen between AC5 and AC10 images and these were reported identically. No significant difference (p > 0.05) in count density was observed between corresponding segments of AC5 and AC10 studies. This despite the fact that mean transmission count density through the heart for 5 s/vw transmission searming was low, varying between 3 (range 0.5-13) counts/pixel (c/p) for posterior views to 7 (range 3-14) c/p for lateral views. The same protocol for transmission scanning can be used in slim and obese patients. There is no need to prolong transmission scanning in obese patients.

90.6 WHAT IS THE INFLUENCE OF RESTORATIVE OR SMOOTHING POSTFILTERING ON THE ACCURACY OF MYOCARDIAL SCINTIGRAPHIES USING NONHOMOGENEOUS ATTENUATION CORRECTION ? A. Tausig, R. Walser, P.Knesewitsch, D. Slotty, N. Win, K. Theisen, K. Tatsch, K. Hahn. Dept. of Nuclear Medicine, University of Munich, Germany

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Recently simultaneous transmission-emission (T/E) protocols have been established in myocardial scintigraphy (MS). Users can choose between different postfilters for further processing. Aim of our study was to analyze the differences between two filters recommended by the manufacturor: a Wiener (Wnr) and a Butterworth (Low Pass [LOP]) filter, conceming sensitivity (SN), specificity (8P) and accuracy of T/E-MS. We included 34 controls, 18 patients with myocardial infarction (MI) and 17 patients with coronary artery stenosis >75% (S) in our study, TIE-MS was performed according our one-dayo protocol using a triple head camera (PRISM 3000, Cardio Fan, PICKER). In addition all patients of the study group received a diagnostic cardiac catheter within 3 months. A Gd-153-1inesource was used to establish the transmission projections. Raw-data were iterativly reconstructed and postfiltered as well with Wnr as LoP. A 16-segment semiquantitativ analysis was performed and a segment-specific (SSP) cut-off was used. The optimized SSP-threshold values were obtained by ROCanalysis and came out as SSP-mean minus the 2,2 to 3,0-fold standard deviation (dependent on study type (rest, stress, stress/rest-ratio) and filter selection). LoP Wnr Conclusion: Semiquantitafivly anaSP 91% 94% lyzed T/E-MS using Wnr or LoP postfiltering is highly accurate to SN(S) 92% i 86% :liscdminate MI and S from normal SN(MI) 93% 83% findings. At a comparable specificity Accuracy 92% 90% evel LoP seems to be supedor to Wnr postfiltedng, where SPP-thresholds are mostly lower.

DIFFERENCES BETWEEN WOMEN AND MEN IN THE HETEROGENEITY OF MYOCARDIAL PERFUSION IMAGES: SPECT TL-201, TC-99M SESTAMIBI AND PET RB-82 Robert Eisner and Randolph Patterson. Emory University System of Health Care, Atlanta, GA Women (W) have special issues compared to men (M) due to attenuation artifacts on SPECT myocardial peffusion imaging(MPI) of T1-201. Tc-99m sestamibi(Mibi)for SPECT and Rb-82 for PET have been proposed to decrease attenuation problems. We compared the spatial heterogeneity of MPI in subjects with low clinical probability of CAD: 25M and 25W for PET Rb-g2 and 25M and 29W for tread-mill stress Mibi and rest T1-201. The same computer software was used to generate average and standard deviation polar maps (PMs) from short axis slices. PMs were segmented into 13 regions for quantitative comparisons. PET Rb-g2 MPI showed little heterogeneity with only small differences between M and W. Stress Mibi PMs were virtually identical to rest TI-201 PMs[p=NS for 13 segments, Mibi vs TI-201(M and W)]. Count ratios between different myocardial wall segments: PET-W Mibi-W Tl-W PET-M Mibi-M TI-M S/L L0t*.05 .87_+.06"# .86_~.07" 1.05_+.07 .88t.06"# .87-+.08" A/I 0.97±.08 1.05_+.09"#+ L05±.09"+ 1.01±.08 1.17~.09"#+1.19-+.13"+ where S/L=(Septal/Lateral)wall eounts;A/l=(AnteriorB-nferior)wall ents; *p<0.01 vs PET (same gender);#p=NS vs TI (stone geader);+p<0.01 vs S/L. In summary, PET MPI was tmiform and eliminated the following uncertainties caused by attenuation on SPECT:(I) differences between W and M on stress MPI, (2) the inferior wall "defect" in M, and the lateral wall "hot spot" in W and M. Of note, there was no difference between rest T1-201 and stress Mibi for SPECT in either W or M.

90.8 REVERSE REDISTRIBUTIONIN TL-201 REST-REDISTRIBUTIONSPECT : USEFULFINDINGOR IMAGINGODDITY.'? R. Sciagrb., M.Matteini, P. Pedenovi, G.M. Santoro, G.Bisi, P.F. Fazzini. Nuclear Medicine, University of Florence; Florence, Italy. Reverse redistribution (RR) is a most debated finding in T1-201 scintigraphy. Using planar rest-redistribution (Rest-Red) imaging, RR segments with normal Rest activity were reported to be probably viable, and those with abnormal Rest to be scarred. Aim of the study was to verify this hypothesis in Rest-Red SPECT. We studied with Rest-Red TI-201 SPECT and echocardiography (Echo) 26 patients with previous infarction and left ventricular dysfunction; viability of asynergic segments was evaluated by postrevascularization Echo. RR was defined as a -> 10% decrease of Red activity compared to Rest and was detected in 40/338 segments (12%). According to both baseline and follow up Echo, 75% of no-RR segments and 60% of RR segments were viable (p < 0.05). Among RR segments, 11/12 (92%) segments with normal (> 80%) Rest activity were viable, versus 15/28 (54%) of those with abnormal Rest (p < 0.05). Segments were then grouped according to the Red activity using a 60% cut off value for viability : 88 had Red activity < 60% ; of them 27/61 no-RR (44%) and 12/27 RR (44%) were viable (ns). Conversely, of the 250 segments with > 60% Red activity, 197/237 no-RR (83%) and 12/13 RR (92%) were viable (ns). In other words, although there is an apparent difference between RR segments with normal or abnormal Rest activity, the likelihood of being viable is similar in RR or no-RR segments if Red activity is considered. Thus, RR detection in TI-201 Rest-Red SPECT does not add any useful piece of information to those achievable from the quantitative analysis of Red activity.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday afternoon, April 9, 1997

90.9

Wednesday PM, April 9, 1997

REVERSE REDISTRIBUTION OF STRESS Tc-99m SESTAMIBI IN DUAL ISOTOPE MYOCARDIAL PERFUSION SPECT AS A MARKER OF MYOCARDIAL VIABILITY. F..Alexandcrson.A. Puente.V.Ancona,1). Victoria,DBialostozky,A.Arrnyo. Instimto Nacioinal de Cardiologia 'Ignacio Chfivez". Mexico City,MEXICO. Thalliunt-201 myocardial nptake in late 24 hour redistribution imaging or after reil~iection arc considered the best nuclear protocol to recognize myocardial viability. The significance of reverse redistribution of sestamibi in dual isotope protocol (rest thallium-stress sestamibi.) is uncertain. The aim of this stud}' is evaluate if a better stress sestamibi perfusiou in rest thallium abnormal segments represent viable myocardium, comparing with the findings of 24 hours thallium images. METHOD: We studied 40 censecutive patients with myocardial inlhrctioa. Coronary angiography was perlbnned in all the patients. We used a 3mCi rest "1"I-201 SPECT followed by dipyridamole or physical stress and 25 mCi Sestamibi injection. Patients returned next day lbr 24 bears thallimn redistribution images. Seintigraphic data were read by 2 blinded exports using 20 SPI'CT segment analysis aud each segment was scored using 5 poims scoring system (O=normal, 4=absent uptake)RESULTS: We compare Ihe segments were we found reverse rcdistribufien seslamibi changes (314 segments) with the tindings of late Iedistribatinn thallium images ht the same segments, w'ith a very good concordance (95%). We also analyzed the agreement between reverse redistribution MIBI and 24 hour thallium redistribution based in score

Sessions 95-100

hnprovement:

~

']'lCd:.SSM]I?I .< 2

SCORb 2 IMPROVEMENT Exact n~reement - 9~-% 24 HOUP,S "r[L*~LLIUMREDIS'rRIBLrrION <2 ] Z'2 lS6 25

I "? 2

ID

1;~3

CONCLUSIONS: Tc-99m stress sestamibi in dual isotope protocol is a good metlmd to identil},' viable myocardium in segmeats with reverse redistributien changes.

95.1 TEMPORAL VARIATION IN EFFECTIVENESS OF PROGNOSTIC SPECT Rcry Hachm~ovit&, LesleeJ. Shaw, Howard L~win, Kaen Kesler, Hosen Kiat, Ishac Cobra, Daniel S. Bem~n. CedarsShai Medical Center, L& CA, USA. Although the prognostic value of SPECT is well defix~ed, v~riation in its proglostic p erforrnmceover time is tmdear. We e~mimd the temp oral v ~ t i ~ in the effectiveness of stratification, as measuredby the risk adjusted odds raio (OR) ofabmmaal vs. nl scans. SPECr was vismlly scored using20 myocardialsegnents used a 5 poiat scale (0=hi, 4=absent tracer upt ake).We identified 5183 patients (pts) who underwent stress sestarNbi SPECI'[4104 exerdse (ex), 1079 adenosine (ad)]. Pts were followedup for a mean of 22 m~ths for hard events [HE; cardiac death (72), myo~dial hfarction (48)] and exzluded for early revascuhrization. Lo~stic regressbn was performed in p t subsets using follow-up daa at 3,6,12,18~and24 month tknepoints. At 6 months, ORwas 23 inad and 11 in ex, at 18 months values of both were 5. In exwith no previous CAD, these values were 31 and 20. Condusion: risk adjusted effectiveness o f ~ E C T decreases brine and varies with type of stress and p t history. This has knpticatbns for time ofp t rctesting,

90.10

S105

95.2

THE CLINICAL VALUE OF "REST DEFECTS" IN TECHNETIUM-99m SESTAMIBI: ARTEFACTS OR CORONARY ARTERY DISEASE? J.M Schroeder-Tanka, E.E. van der Wall, M.M.C. Tiel-van Buul, K.I. Lie, E.A. van Royen. Academic Medical Center, Amsterdam, the Netherlands.

ADDITIVE PREDICTIVE VALUE OF SPECT-TL OVER CLIKfCAL PARAMETERS FOR THE OCCURRE.NCE OF CARDb'~C EVENTS IN DIABETIC PATIENTS. G. Vanzetto, O. Ormezzano,T. Hammoud, D. Fagret, S. Halimi, P.Y. Benhanlou, D. Cordolmier, P, Deqnemle, J. Machecolm. University Hospital, Grenoble, France.

Introduction: Rest defects (RD) after exercise Tc-99m Sestamibi SPECT were defined as normal uptake on stress and decreased uptake on rest imaging is interpreted as an artefact. However, since RD has been associated with coronary artery disease, we studied the cardiac event rate in patients with RD and no additional ischemia. Methods: We studied 460 consecutive patients with known or suspected coronary artery disease who underwent diagnostic or prognostic Tc-99m Sestamibi SPECT. The SPECT images were visually and semi-quantitatively analyzed. Results: 161 rest defect segments were noted in 30 pts (6.5%): 67% inferior posterior wall (~:o" = 1:6); 30% anterior wall (;:o" = 2:1) and 13% septal wall (~:e = 1:1). RD was more frequently present in men than in women (2:1). 12 pts. had no cardiac history of myocardial infarction, CABG or PTCA. Follow-up was 18 + 8 months. Based on follow-up, RD was assiociated with: • Hard cardiac event (cardiac death/infarction) 3,3% • Soft cardiac event (CABG, PTCA) 9,9% - PTCA in other segment 6,6% - PTCA in segment of RD: 3,3% Conclusion: Rest defects without additional ischemia is not uncommon (6,5%). Localization and sex-distribution of RD was similar to that of previously reported "artefacts". This study supports the relation between RD and coronary artery disease in a small group of patients.

The aim of this stu@ was to assess if SPECT thalhmn has an additive value lbr the prediction of futare CV evems hi an ash~:nptomaticby high risk selected cohort of diabetic patients. 202 pts (137 males, 65 fen~tes, age 59_+11 3qcs) were pmslx~tively screened with stress-RI-lq SPECT (exercise n=103, dip}ridamole 1l=99). r)~e I diabetes meltims was present in 46 pts mid t}pe Ii hi 156 pts, 40 of them being under insulin therapy. 163 pts (76%) had no histo~' of CV disease, but all pts had 2 risk factors or more; 56% presented a diabetic nephropaNy and 32% a micmalbuminuria. They were tbllowed lbr an average period of 25 months (range 4-74 mouths) with a systematic clinical and ECG control at the end of the follow up. Kaplan-Meyer survival analysis was pertbrmed. Results : The major eveut rate was 6.8% / year (10 pts CV deaths, 18 pts non fatal MI). Other CV events (unstable angina, cougestive heart thilure, need for myocardial revasculanzation) eccured in 25 other pts. In univariate analysis, the clinical predictors of fataI outcome were age > 60, a low body ~veight, a Insmry of coronary, artery disease, film presence of miemalbumimwia, an abnormal rest ECG, the presence of three or more abnormal seoonents on SPECT-T1. However, tour patieats died during Ibllow up in spite of an initial normal SPECT-T1. In multivariate analysis, only two independmlt predictors were significant for occurrence of major events : age over 60, and the presence of more than two abnormal detect on SPECT-TI. Conclusion : SPECT-T1 has an additive predictive value over elininal parameters. However, only the presence of a large defect is of predictive value watever the t~l~e of defect reversible or fixed defect. Morever the negative predictive value is lower than in the general population.

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Abstracts Wednesday afternoon, April 9, 1997

95.3 PROGNOSTIC VALUE OF ABNORMAL MYOCARDIAL SPECT IN DIABETICS W I T H NORMAL EPICARDIAL CORONARY ARTERIES D Groat, Y America, ZX He, JJ Mahmarian, MS Verani. Baylor College of Medicine, Houston, TX, USA We evaluated the prognostic value of stress myocardial SPECT in diabetic patients (pts) with angiographically normal coronary arteries. Thirty-nine such pts (21 males, 18 females, mean age 58+12 years) were included. Pts with previous coronary bypass surgery or angioplasty were excluded. Fourteen pts had a normal stress SPECT, whereas 25 pts had an abnormal SPECT study. Among the latter, perfusion defects were totally reversible in 14, partially reversible in 5 and persistent in 6 pts. The defect size (% LV) measured 16-+8%. Thirty-five pts were followed-up for a mean period of 25+18 months, and 4 were lost to follow-up. A total of 10 cardiac events were observed: cardiac death (n=2), nonfatal myocardial infarction (n=2), heart failure (n=3) and unstable angina (11=3). The cardiac event rate was 39% (9/23) in pts with an abnormal SPECT, compared to 8% (1/12) in pts with a normal SPECT (p=0.05). Thus, despite having normal epicardial coronary arteries, diabetic pts with an abnormal stress SPECT study are at increased risk for cardiac events.

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Journal of Nuclear Cardiology January/February 1997, Part 2

95.5 Exercise Technetium 99m Sestamibi SPECT after Coronary Artery Bypass Surgery. A.Desideri,G. Candelpergher, P.Zanco,G. Suzzi,N.Borsato, G.Fedin oL.Celegon. S.Giacomo Hospital, Castelfranco Veneto (TV), Italy We assessed the prognostic in_formation obtained with exercise sestamibi SPECT scintigraphy performed for routinary follow up or reappearance of symptoms atter Coronary Artery Bypass Surgery (CABG). We studied 75 patients (pts) referred to our Center at a mean of 38+-53 months from the revascularization procedure and prospectively followed them for 38+-24 months. Fifteen pts (20%) had events(CE) : there were 4 cardiac deaths, 3 nonfatal AMI, 8 late revasculafization procedures (4 PTCA and 4 repeat CABG). Univariate analysis identified a history of typical angina (p=0.001), a clinically positive ergometric test (p=0.009), peak exercise heart rate (p=0.0003) and scintigraphie summed reversibility score (p=0.014) as predictors of CE. Using multivariate logistic regression analysis, the best and only significant predictor of CE was the summed reversibility score (p=0.008).We conclude that exercise sestamibi SPECT scintigraphy provides optimal prognostic information after clinical and ergometric parameters in patients with previous CABG.

95.4

96.1

Transient lschemic Dilation Identifies Risk of Subsequent Cardiac Events TJ Fisher, RG Schwartz, C Thompson, T van Geel, J Carleo, J Leon. University of Rochester, Rochester, NY

P R E D I C T I O N OF P O S T - R E V A S C U L A R I Z A T I O N F U N C T I O N A L RECOVERY W I T H SIMULTANEOUS, COMI]INED D O B U T A M I N E E C H O C A R D I O G R A P H Y A N D PERFUSION I M A G I N G l.Vassiliadis, A.Fountos,A. Papademetriou,K.Dimas,l.Kallikazaros, E. Sbortias, P. Strembelas,A. Koroneos.Athens Naval Hospital,Athinai, Greece

Transient ischemic dilation (TID) by SPECT myocardial perfusion imaging (MPI) accurately identifies severe and extensive coronary artery disease (CAD), and limited data suggest its prognostic utility. To evaluate further its prognostic value, we compared cardiac death + nonfatal MI (HARD), and revascularization (CABG, PTCA) events for > 1 year after MPI in t54 patients (pts) with TID and in case matched controls (CMC) with abnormal scans but no TID studied between 7/1/93 and 6/30/95. MPI N= HARD CABG PTCA TID 154 15 (9.7%) 45 (29%) 15 (10%) CMC 154 7(4.5%) 12 (7.8 %) 7(4.5%) WNL 331 2 (0.6%) 5 (1.5%) 5 (1.5%) Compared to CMC, pts with TID had higher mean LV volume ratios by quantitative 3-D wall parameterization method (1.21 +/- 0.14 vs. 1.10 +/- 0.13, P<0.001), and more frequent cardiac events (P<0.001, McNemar's test), despite similar LVEF (45 +/- 17% vs. 44 +/- 18%) and exercise duration. We conclude TID by SPECT MPI identifies risk of morbid isehemic events.

Thallium Perfusion Imaging with reinjection (SPECT-R) and Dobutamine Stress Echocardiography (DSE) are currently applied to identify myocardial viability. We compared these two methods in their ability to detect post-infarction viability and their accuracy to predict post-revaseularization recovery. Thirty pts with prior myocardial infarction and impaired left vcntricular funetinn were assessed with simultaneous,combined SPECT-R and DSE. Sixteen pts were allocated Io receive interventional treatment (PTCA = 9,CABG = 7) based on viability criteria:wall motion improvement/worsening o f systolic thickenning by DSE and thallium re-uptake o f more than 5007o by SPECT-R. Of the 150 segments with persistent defect,58(37~0) demonstrated re-uptake. A positive response to Dobulamine infusion was detected in 48(83%) of the 58 segments by DSE. Dobulamine had no effect in 46(49°70) of the 94 segments, characterized by thallium-as non-viable. O f the 44 snccesfuUy reperfused segments,IS(41%) demonstrated functional recovery on the follow-up study.The prediction of reversible isehemic dysfunction by SPECT-R and DSE demonstrated respectively and sensitivity of 93070 vs7807e,specificity of 7707o vs 86070 and predictive accuracy of 86% vs 60%. A moderate agreement (K = 0.52) was achieved by the two methods, assessing the concordant results on viability, while a better correlation (r =-0.75) was found in the prediction of segments demonslrating post-revascularization recovery . Our data suggest that SPECT-R and DSE exeibiled a satisfactory degree of sensitivity in predicting the revascularization outcome of the hibernating myocardium. SPEC"r-R appears to be more accurate in assessing the extent of viability.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday afternoon, April 9, 1997

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96.4

DOBUTAMINE ECHOCARDIOGRAPHY VERSUS THALLIUM-201 SPECT FOR DETECTION OF VIABLE MYOCARDIUM AFTER ACUTE INFARCTION GK. Lurid, RM. Ht~ppner, V.M. Heinrichs*, M. Ltibeck*, CA. Nienaber. Dep. of Cardiology and *Dep. of Nuklear Medicine, UKE, Hamburg, Germany

COMPARISON OF MRI AND SPECT WITH RESPECT TO WALLMOTION AND GLOBAL LEFT VENTRICULAR FUNCTION S. Nekolla, J. Neverve, J. Stollfut3, M. Schwaiger Technische Universit~.t Menchen, Germany The assessment of regional and global parameters of W-function has become possible. We developed an automated method and validated global and regional LV-function by comparison by gated MRI. Ten normal volunteers and 15 patients with coronary artery disease (EF=33+15%) were investigated. Endo- and epicardial boundaries from MR data were delineated manually by two observers. The corresponding boundaries from SPECT were extracted by an geometrical analysis of the myocardial walls using threshold techniques and spatial and temporal constraints. Regional parameters were determined in 4 LV segments excluding the apex. There was a good correlation of global parameters and and an acceptable relationship between regional parameters.

Dobutamine echocardiography (DE) and thallium-201 SPECT (T1-201) reflect two different concepts for assessing viable myocardium; however, the diagnostic impact of both methods early after acute myocardial infarction (AMI) is unknown. We prospectively investigated 48 parents (age: 55 +11, 6 f, 42 m) 10 +4 days after AMI (peak CK: 1165 _+940 IU/mL) by DE and rest-redistribution (4 h) TI-201 SPECT imaging. In all cases the infarct vessel was revascularized by thrombolysis or staged PTCA. Results: Calculation of test accuracy was based on 193 akinetic segments at baseline, of whom 108 segments (56%) revealed improved contraction at follow-up echocardiogramm 5.9 +_3.7 months after AMI. Sensitivity Specificity Accuracy DE 81 87 83 TI-201 90 49* 72 (*p<.0l) Conclusion: Due to its superior specificity low dose DE should be favoured for identification of viable myocardium in the early post-MI period.

Ejection fraction LV Mass Endocardial shortening Myocardial thickening

slope 1.05 1.12 1,03 0.87

r 0.85 0.82 0.78 0.73

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p <0.05 <0.05
Thus, an integrated analysis approach for SPECT pertusion studies yields accurate parameters of LV=function. Furthermore, regional wall motion can be quantified by geometrical means, which may offer advantage in the presence of perfusion defects over count-based techniques.

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96.5

COMPARISON OF DOBUTAMINE STRESS ECHOCARDIOGRAPHY AND MIBI SPECT IMAGING FOR THE DIAGNOSIS OF CORONARY ARTERY DISEASE IN HYPERTENSIVE PATIENTS WITH AND WITHOUT LEFT VENTRICULAR HYPERTROPHY. Abdou Elhendy, Jos RTC Roelandt, Marcel L Geleijnse, Peter R Nierop, Galal M El-Said, M Mohsen Ibrahim, Medhat El-Reface, Paolo M Fioretti. Thoraxcenter, Rotterdam, The Netherlands.

TOMOGRAPHICGATED BLOODPOOL$PECT (G-SPECT) FOP, ASSESSMENTOF REGIONALLEFTVENTRICULARFUNCTION IN COMPARISONTO ECHOCARDIOGRAPHY. A.Terzi, A.Vignati°, E.Milan, O.Zoccarato§, A.Vaccari, L.Facchetti, G.La Canna, R.Giubbini. Nuclear MedicineServices, Civic Hospitals of Brescia, Busto-Arsizio° and Veruno MedicalCenter§.

Background. Stress echocardiography was reported as an accurate method for the diagnosis of coronary artery disease (CAD) in hypertensive patients (pts). In contrast, the specificity of myocardial perfusioa scintigraphy in these pts was questioned. However, these imaging modalities have not been compared in hypertensive pts. Methods. Dobutamine (up to 40/~g/kg/min) stress echocardiography (DSE) in conjunction with MIBI SPECT was performed in 84 hypertensive pts. Ischemia was defined as new wall motion abnormalities at DSE and reversible perfusion defects at SPECT. Results. 66 pts had significant CAD (->50% diameter stenosis). Sensitivity, specificity and accuracy of ischemia at DSE for the diagnosis of CAD were 73%, 83% and 75%. Those for MIBI were 67%, 83 % and 70% resi)ectively. Significant CAD was detected in 123 (49%) of the 252 analyzed arteries. Sensitivity, specificity and accuracy of DSE for the regional diagnosis of CAD were 63%, 90% and 77%. Those for MIBI were 58%, 91% and 75% (p = NS vs DSE). Left ventficular hypertrophy (LVH) was detected in 59 pts and did not influence the overall or regional specificity of DSE or SPECT. Conclusion. DSE and MIBI SPECT have a comparable accuracy for the diagnosis of CAD in hypertensive pts. These pts should not be considered as unsuitable candidates for stress myocardial perfusion scintigraphy in presence or absence of LVH.

The assessmentof regional wall motion (RWM) by planar equilibrium radionuclide venldculography is cdfdcal due to two-dimensional imaging and its clinical use is progressively declining in favour of ECHO. Aim of this studywas to compare G-SPECTand lrans-thoracic ECHO for the evaluationof RWM. G-SPECTwas acquired over 180° at 16 frames per cardiac cycle, after Tc-99m-pyrophosphate in rive labellingof red blood cells. Short, ve~cal and horizontallong axis slices were exlractedfrom fransaxial tomograms. A 16 segment model was adoptedfor the comparison with ECHO RWM, gradedaccordingto a 4 grade score. For each one of the 16 segmenls the normal range of GSPECT EF was quantified and a normal data file was defined; the average value -2.5 SD was used as a lower threshold to identify abnormal segments. In addition amplitude images from Fourier analysiswere quan~ed and consideredabnormalwhen below 50% of the max. In a study group of 27 consecutive pts, the regional EF normal data base and the amplitude analysis allowed correct identificalion of 132/146 and 109/146 asynergic segments by ECHO, and of 256•286 and 232/286 normal segments, respectively. Therefore sensi~ty, specificity and overall accuracy to detect RWM abnormalities were 90%,89%,90% and 74%,80%,79% for regional EF and amplitude analysis, respectively.G-SPECTis a reliable tool for RWM evaluation,well correlated to ECHO, less subjec~e and able to provide quantita~e data.

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97.1 EXERCISE AND VASODILATOR STRESS MYOCARDIAL PERFUSION SPECT IMAGING FOR THE DETERMINATION OF NORMALCY RATE AND THE EFFECTS OF ATTENUATION CORRECTION Robert C. Hendet, William P. Follansbee, Daniel S. Berman. Northwestern U. Med. Sch., Chicago, IL The impact of the method of stress testing on the normalcy rate of myocardial perfusion SPECT and the interaction with attenuation correction (AC) techniques is unknown. Accordingly, we examined 164 pts with a <5% likelihood of CAD; the mean age was 52+12 years. Treadmill exercise testing (Ex) or vasodilator stress testing with either dipyridamole or adenosine (Vaso) was performed in 130 and 34 pts, respectively. Perfusion imaging with and without AC was performed following the injection of Tc-99m sestamibi at peak stress. Image quality was good or excellent in more pts with Ex than with Vaso, for both uncorrected images (91% vs 78%; p<0.05) and with AC (98% vs. 91%; p<0.05). The concordance between uncorrected and AC scans in the anterior region was greater for Ex (81% ) than with Vaso (65%; p<0.05). The normalcy rates for uncorrected Vaso and Ex was 74% and 88% (p<0.05), with AC Ex also higher than with Vaso (95% vs 79%; p<0.005). Conclusion: Image quality and normalcy rates are superior with Ex compared with Vaso, irrespective of whether or not AC is applied. Additionally, AC improves the normalcy rate when using either Ex or Vaso testing.

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Journal of Nuclear Cardiology January/February 1997, Part 2

97.3 IMPROVED DIAGNOSTIC ACCURACY OF SPECT BY ATTENUATION CORRECTION IN PATIENTS WITH LARGE BODY HABITUS ZX He, NM LakkJs, Y America, D G-root, SM Badruddin, AA Ahmad, JJ Mahmarian, MS Verani. Baylor College of Medicine, Houston, TX, USA Photon attenuation in patients (pts) with a large body habitus or large breasts hampers SPECT accuracy. Accordingly, we evaluated whether attenuation correction (AC) improves the accuracy of SPECT in 77 such pts who also had coronary angiography (52 with and 25 without significant [>50%] coronary stenoses). There were 44 men (weight 230+_34 lbs) and 33 women (weight 187+44 lbs; bra size 32c-44dd). Stress sestamibi SPECT was performed with simultaneous acquisition of emission and transmission data. Tomograms without AC were assessed first without (strategy A), then with • clinical information (strategy B). Tomograms were later interpreted alter AC (strategy C). The sensitivity of SPECT was similar with all 3 strategies (82%, 73%, and 79%, respectively). The specificity improved slightly with strategy B vs A (48% vs 32%, p=ns), and further improved with Strategy C (76%, p=0.042 vs strategy B). Thus, AC improves the specificity of SPECT in pts with a large body habitus without decreasing its sensitivity.

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97.4

NON-TRANSMISSIVE ATTENUATION AND SCATTER C O R R E C T I O N (ASC) O F ~'=Tc C A R D I A C S P E C T IN N O R M A L S AND P A T I E N T S W I T H ADVANCED CAD G.Schulz, J.Kupferscld~ger, H.J.Kaiser, J.v.Dahl, U.BueU. Aachen University of Technology, Germany

IMPROVED 2°~TLUNIFORMITYWITH ATTENUATIONCORRECTION IN PATIENTSWITHLOWRISKFORCAD E Prvulovich, AHR Loire, 1 Bomanji, PH Jarritt, PJ Ell University College London Medical School, UK

To evaluate the clinical use of an ASC method without transmission measurement as it was developed in this laboratory, two groups were examined at rest: (i) 44 patients with angiographically proven CAD and (ii) 10 normals. 40 minutes alter injection of 400 MBq ~ c MIBI SPECT was performed using triple-energy window acquisition for primary, scatter and backseatter photons, 2x180", matrix 1282. Following filtered backprojectiun (Butterworth 5~ order, cutoff 0.3) with and without ASC, counts of 33 left ventficular regions were normalized to the region with highest perfusion. We compared relative MIBI uptake with/without ASC according to myocardial topegraphy and supplying coronary artery, subelassified depending on MIBI uptake (normal ~70%, severely reduced <50%). ASC increased counts in all regions of both groups. In normals, the highest effect was observed in the RCA territory. Uptake values were increased in posterior wall regions by 4.8 +9.9%, whereas in apical regions values were decreased by 4.2 :k5.6%. In patients with CAD, effects of ASC were more depending on perfiasiun conditions as on topography: uptake values were increased in normal regions by 1.8 +9.6% and decreased in regions with severe reduced perfnsion by 6.2 +8.6% independently of the supplying coronary artery. The developed ASC method improved homogeneity of SPECT imaging in normals but enimneed the contrast between peffusian defects and remaining myocardium. Thus, ASC improved discrimination between reduced and normal perfnsion by SPECT.

Regional variation of tracer distribution is seen in uncorrected (NC) 2°1T1 SPET images of normal hearts. This study evaluates the effect of attenuation correction (AC) using sequential emission/transmission imaging on myocardial 2°3Tldistribution in 36 patients (14 M, 22 F) with low (< 5%) risk of coronary artery disease (CAD). Methods. Pharmacological stress and delay data were acquired using an L-shaped dual headed camera (GE, Optima) fitted with two mGd scanning line sources. Images were reconstructed with and without AC. Polar plots were generated for each data set and count density assessed in 17 myocardial segments. Results. Population % standard deviation (sd) for each segment of AC data was smaller (p < 0.001) than that for NC data. In addition, AC studies had improved anterior : basal inferior activity ratios compared to NC studies (p < 0.05 in all cases) suggesting compensation for basal attenuation. men

NC

women

AC NC AC % sd of segmental counts stress 8.2 3.9 6.7 3.1 delay 8.4 4.1 5.3 2.8 Mean anterior : basal inferior ratio stress 1.18 0.97 1.05 0.97 de]ay 1.19 0.99 1.06 0.95 Attenuation correction leads to improved homogeneity of myocardial tracer distribution in patients with low risk of CAD.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday afternoon, April 9, 1997

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98.2

ATTENUATION CORRECTION OF MYOCARDIAL SPET IMPACT ON DIAGNOSTIC ACCURACY R. Kluge, W. H. Knapp. Dept. of Nuclear Medicine, University of Leipzig, Germany. Irregular photon attenuation may limit the accuracy of myocardial SPET. The aim of the study was to assess the benefit of attenuation correction (AC) for the detection of CAD and for the identification of the involved coronary artery territories. 30 male patients with single-vessel disease (10 patients for each group with >_ 50 % stenosis of RCA, LCX and LAD) were investigated with and without AC. Stress studies were performed with 400 MBq Tc-99m-tetrofosmin and an A D A C Vertex camera equipped with two scanning Gd153-line sources.Results were quantified using circumferential count rate profiles. Normal range was determined by SPET analysis of 25 male patients with a likelihood for C A D o f < 5 %. In AC studies, extent and severity of defects were more clearly represented. ROC-analysis of CAD-detection revealed at a sensitivity-level of 95 % speeificities of 82 % (NC) and 95 % (AC) in the RCA-region and 65 % (NC) and 100 % (AC) in the LCX region. Thus, AC improves the detection o f CAD in quantitatively evaluated SPET studies, in particular in the RCA- and LCX-territories.

INCREASED STRESS RIGHT VENTRICULAR (RV) A C T M T Y ON DUAL ISOTOPE SPECT: A SIGN OF MULTIVESSEL AND/OR LEFT MAIN CORONARY ARTERY DISEASE (CAD). K. A. Williams, C. M. Schneider. The University of Chicago, Chicago, IL, USA. In patients (pts) with multivessel CAD, SPECT peffusion imaging without absolute quantification of regional flow, evaluates relati~,,;~e left ventricular (LV) tracer uptake and may give "false negative" results with global hypoperfusion or in the distribution of a vessel • which is less diseased than contralateral vessels. We hypothesized that in pts without proximal fight CAD, RV tracer uptake could serve as an indicator of relative global LV hypoperfusion. Rest thallium-201 (REST) and exercise (EX) 99~Tc-sestamibi or 99~Tetetrofosmin SPECT peffusion images analyzed for peak RV and LV activity. (RV:LV) in 37 pts with multivessel and/or left main (LM) CAD and in 37 pts with no evidence of CAD. Results: The normal values of RV:LV was 0.32±0.07 at REST and 0.34:t:0.06 with EX. In pts with CAD, the REST values were similar (mean 0.34:t:0.08, p=NS) but mean EX RV:LV was significantly higher (0.43-~0.10, -p<0.001, Figure 1). Pts with the highest EX RV:LV were those with severe (270%) LMCAD with a lesser degree of or absent proximal right CAD (0.52-40.5, n=8, p<0.001 vs. normal and other CAD pts); the criteria of EX RV:LV >0.42 with a EX:REST ratio > 1.2 was 100% sensitive for this pattern of CAD, with no false positives in the normal group. Conclusions: Increased EX RV:LV, especially if reversible, is indicative high-risk CAD, particularly Figure 2. NonnalRI~'LVat high grade LM with absent or less severe rest, inctvased at swess, proximal fight CAD.

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98.3

QUANTIFICATION OF DEFECT SIZE AND SEVERITY IN A THREE - STE~ MYOCARDIAL IMAGING PROTOCOL. M. Gabain, S. Guedira, L. Bontemps, tL Itd, T. Benoit, P. Rigo. Cardiovascular Hospital, Lyon, France and University Hospital, Liege, Belgium.

MYOCARDIAL VIABILITY AFTER THROMBOLYSIS BY 99M-TC-TETROFOSMIN SPECT" COMPARISON WITH 201-TL REST AND DELAYED (LATE) REST IMAGING. M. Gyongyosi, M. Haddad, P. Yang, A. Hassan, M. Gottsauner, D. GIogar, H. Sochor Dept. of Cardiology, University of Vienna, Austria Myocardial uptake of 201-TI and 99m-Tc-Tetrofosmin (99mTc-Tetro) was compared in patients post AMI and thrombolysis to evaluate 99m-Tc-Tetro perfusion imaging for assessement of myocardial viability. Results were also correlated with quantitative coronary angiography (QCA). 12 patients (51_7 y) underwent rest and 3 h late rest 201-TI SPECT and 99m-Tc-Tetro-Dipyridamole stress-rest SPECT 7_+3days after AMI. Quantitative data of myocardial uptake (UPT) of both tracers by polar map analysis (PM) were compared. Total myocardium from PM in 72 sectors in 6 short-axis slices, and % UPT was calculated in 3456 sectors and extent of perfusion defects expressed as numbers of sectors with <80% UPT. Average % UPT in perfusion defects was determined as mean_+SEM UPT in abnormal sectors. In spite of the 81_+5% area stenosis of the infarct-related artery by QCA, only 3 pts displayed stress-induced perfusion defects by 99m-Tc-Tetro. 6/12 pts exhibited improved % UPT in the late 201-TI scan, while 4 pts demonstrated paradox redistribution. In summary, 8/12 patients suggested residual viability based on >50% 201-Tt UPT at the late rest image. Quantitative 99m-Tc-Tetro resting uptake data indicated a better correlation with delayed rest 201-T1 uptake (r=0.835, p<0.05), vs early rest 201-T[ uptake (r=0.797, p<0.05) for all myocardial sectors. Extent of resting perfusion defects by 99m-TcTetro correlated only with the extent of delayed resting 201-TI perfusion defect (r=0.73, p<0.05) but not with that of early rest 201-TI defect (r=0.37). Mean % UPT in the region of resting defects for initial 201-TI, delayed 201-13 and 99m-Tc-Tetro was 65~_2,67_+2and 67_+2%, respectively. In 22/29 sectors with early 201-TI % UPT <50% (severe defect), late TI-rest was unchanged. 22/26 segments were identical by 99m-Tc-Tetro rest. Thus, 99m-Tc-Tetro can provide comparable information to 201-TI uptake for the assessment of myocardial viability pts after reperfusion therapy.

Combining rest redistribution thallium with stress MIBI myocardial imaging seems to be optimal for assessment of both isehemia and viability after myocardial infarction. This protocol has been evaluated in retain of fixed defects, partially reversible defects and reverse redistn'bution, using a quantification software fIB and PR) in a group of 36 patients in which the question of viability was raised. SPECT acquisitions were performed 15 rain after thallium-201 rest injection, 4 hours later (redistribution) and 1 hour after stress teclmetium-99mMIBI injection. Defect size and severity, expressed in %, were computed from a polar map constructed using long axis pieslices. Patients were classified in 3 groups : fixed defects (F= llpts), partially reversible defects indicating isehemia (I = 16pts) and reverse redistribution (R = 9pts) : group l (F) group 2 (I) group 3 (R) stless 23.7+/-15.6 34.0+/-13.4 21.1+/-11.0 rest 24.0+/-14.4 25.0+/-12.1 21.6+/-10.2 redistribution 23.6+/-14.8 23.1+/-10.0 25.8+/-10.8 These results demonstrate the technical feasability of a quantitative analysis of tomograms obtained with biologically different tracers and different gamma energies. This protocol may be adequate for myoc~dial tissue characterization, with quantification of the different components such as normal myoeardium, stress or resting ischemia, cellular viability and myocardial thallium clearance, in partially infarcted territories.

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Abstracts Wednesday afternoon, April 9, 1997

98.4 ASSESSMENT OF MYOCARDIAL VIABILITY BY DOBUTAMINE STRESS ECHO AND SIMULTANEOUS TC99M-TETROFOSMIN/18-FLURODEOXY-GLUCOSE SPECT

Riccardo Rambaldi, Don Poldermans, Jeroen Bax, Paolo M. Fioretti, Eric P. Krenning, Roelf Valkema. Thoraxcentre and Department of Nuclear Medicine, Erasmus University, Rotterdam, The Netherlands. Aim of the study: To compare dobutamine-atropine stress echoeardiography (DSE) and simultaneous perfusion/metabolism SPECT imaging for the assessment of myocardial viability in pts with severe left ventricular dysfunction prior to coronary revascularization. Methods: 41 pts with a mean ejection fraction of 30% (range 11 to 49%) were evaluated by DSE and Tc99m-tetrofosmin/18-flurodeoxyglueose SPECT at rest. A 16-segments/5 point scoring model (normal wall motion, mild or severe hypnkinesis, akinesis, dyskinesis) was applied to DSE. Only segments with severe dyssynergy at rest Were scored for viability according to: I) biphasic pattern (initial improvement and worsening at peak dose); 2) decreased wall thickening at any dobutamine dose; 3) improved wall thickening at any dobutamine dose. An accordingly 16 segments/5 point scoring model was applied to SPECT. Severely dyssynergic segments were considered viable in presence of simultaneous perfusion/metabolism mismatch, normal perfusion/metabolism and mild matched defects. Results: 267 of 656 segments (41%) had severe hypokinesis at rest. Myocardium was judged viable in 54/267 (20%) segments by low dose DSE, in 65/267 (24%) by full dose DSE and in 67/267 (25%) by SPECT. 11/65 (17%) viable segments were recognised only by full DSE. The agreement for myocardial viability between LDDE and SPECT was 71% (kappa: 0.24) and between full DSE and SPECT 73% (kappa 0.28). Conclusions: 1) Myocardial viability in severely dyssynergic segments was detected by DSE and perfusion/metabolism SPECT with a poor correlation. 2) The inclusion of segments with ischemia and delayed improvement during full dose of dobutamine-atropine allowed the detection .of an additional 17% viable segments.

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Journal of Nuclear Cardiology January/February 1997, Part 2

99.1 EXTENT OF MYOCARDIAL DENERVATION DETECTED WITH I123-MIBG CORRELATES WITH DECREASED HEART RATE VARIABILITY IN THE EARLY POSTINFARCT PERIOD ABentrup,HD.Esperer,E.Hecht,S.Braune,H.J.Otto,H.Klein Otto-von-Ouericke tJniversi~ Magdeburg, Germany The integrity of sympathetic myocardial innervation has: previously been shown an independent risk factor in patients following myocardial infarction (MI). Our study' tested the hypothesis, whether reduced regional 1-123-MIBG-uptake in hibernating myocardium correlared with heart rate variabiliy (HRV) reduction. We performed double nuclide SPECT i,aaging with T1-201 and 1-123-MIBG 4 h p.i. in 25 patients aged 64-+11 ys 2 to 3 weeks post MI. Segmental mismatch of uptake in TI/MIBG images was graded as absent/slight (S) and moderate/extended (E).In each patient coronary angiography was performed and 24-hour HRV assessed. In 1 l patients with mismatch category E HRV was significantly reduced compared to 14 patients with mismatch category S (R-Rcycle variability: 76+19ms vs 1 13+20ms, p<0.05; root mean square of successive R-R differences:16+ 4 vs 29_+ 9 mps, p=0.03). Single vessel disease was present in 90% of the pts, with S whereas only in 20% of the pts with E (p<0.05). There were no significant differences regading LVEF, age and infarct localisation.We conclude, that 1) segmental mismatch in delayed Tt/MIBG images is strongly correlated with HRV reduction and 2) the severity of coronary artery disease seems to be a major determinant of sympathetic denervation.

98.5

99.2

DOES STRESS AND REST PEP.FUSION IMAGING PREDICT CULPRIT VESSEL STATUS POST MYOCARDIAL INFARCTION. M. Freeman, S. Goodman, T. Hsia, J. Sloninko, C. Hill, A. Langer. St. Michael's Hospital, Toronto, Canada

GENDER UNIFORMITY WITH SPECT IMAGES OBTAINED WITH ATTENUATION C O R R E C H O N (AC) AND E N H A N C E D ACQUISITION METHODS. J,R. McClellan, J. Viggiano, A. Alavi, L.I. Araujo University of Pennsylvania, Philadelphia, PA.

To non-hwasivelypredict culprit vessel (CV).status early following acute myocardial infarction (MI) we performed coronm'yangiography and TcsestaMIBI (MtBI) at rest (R) and with dipyridamole (Dip) and R and 24 Ill"redistribution(Red) thallium (TL) imaging in 131 consecutive pts. The CV was identified by angioga'aphyand stenoses ga'adedas <50%, 50 to 99%, and 100%. Each SPECT perfasion study was scored in 13 segments (0-normal to 4-no uptake) with 2 observers blinded to clincial and angiographic data. 133' comparison to Dip MIBI, we defined reversibility (REV) as a decrease in segmental score in the CV territory (TER) of :'2, worsening (WOR) if score increased by ~2, nonrev~,msibilib,(NR) as no change:, 1 and normal (NL) as Dip score of 0. In 8 pts flteRED stu&,couldnot I.~ haterpreted. The results according to CV stenosis are shoran in the table: Dip MIBI- R MIBI Dip MIBI- R TL Dip MIBI- Red T 1 CV to99%1 <50%5000% <50% 501099% 100% <$0% 50to99% 100',4 NL 6(52%)14(15%)2(10%) 6(32%) 12(13%) 1(5%) 6(32%) 12(14%) 1(6%) WOR I(5%) 5(5%) 0(0%) 3(16%) 3(3%) 1(5%) 5(26%) 16(1~¢,) 3(17%) NR 9(47%)36(39%)6(30%) 4(2I%) 20(22%) 5(25%) 4(21%) 20(23%) 3(17%) REV 3(16%)37(..~)%)12(60%) 6(32%) 57(62%) 13(65%) 4(21%) 38(44%)10(56",.) REV of dip MIBI defect was more common with R TL (76/131,58%) than with R MIBI (52/131, 40%) or Red TL (52/123, 42%), p<0.05. WOR was most colmnon with Red TL (24/123,18%) than with R MIBI or R TL (6/131 and 7/131, 5%) p
Enhanced procedures may improve the accuracy of SPECT imaging. R e s t Tc-99m s e s t a m i b i s t u d i e s w e r e a n a l y z e d i n 39 p a t i e n t s (pt) (20 w o m e n ) w i t h <5% l i k e l i h o o d of C A D u s i n g a 3 - h e a d e d P i c k e r 3000xp w i t h a G a d - 1 5 3 s o u r c e for A C w i t h 360 ° orbit and reconstruction with an expectation maxm i n l i k e l i h o o d a l g o r i t h m . I n e a c h pt, 8 r e g i o n s o f i n t e r e s t (ROI's) o n 3 s h o r t axis slices w e r e a n a l y z e d w i t h a n d w i t h o u t AC. In t h e 936 R O I ' s a n a l y z e d , t h e s t a n d a r d d e v i a t i o n for A C r e g i o n s w a s l o w e r t h a n n o n - A C r e g i o n s (9.9 vs. 12.5, p =0.02) w i t h s i m i l a r f r e q u e n c y i n m e n a n d w o m e n . In n o n - A C i m a g e s , 121 (12.9%) w e r e <85% o f t h e m e a n i n inferior and septal basal regions and AC improved t h e s e a r e a s ( m e n 0.78 to 0.87, w o m e n 0.75 tO 0.86, p<0.001). O f t h e R O I ' s >1.15 of m e a n , 73% w e r e a n t e r o l a t e r a l a n d i m p r o v e d w i t h A C ( m e n 1,18 to 1.09, w o m e n 1.14 to 1.10, p<0.001). I n m e n a n d w o m e n , c o u n t u n i f o r m i t y is i m p r o v e d with AC and current acquisition protocols.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday afternoon, April 9, 1997

S 111

99.3

99.5

DETERMINANTS OF INCREASED Te-99m SESTAMIBI LUNG UPTAKE G. DePuey, A. Rozanski, K. Nichols, H. Salensky. St. Luke's-Roosevelt Hospital and Columbia Univ., New York, NY

SYMPTOMS VS EXERCISE-INDUCED DEFICIENCY

To evaluate the relative importance of resting LV dysfunction and stress induced myocardial ischemia as determinants of Te-99m sestamibi lung uptake, 4 patient (pt) groups were studied: 1) 76 pts with a < 10% likelihood of coronary disease with normal stress and rest perfusion scans and normal LVEF (normals); 2) 75 pts with prior MI, fixed perfusion defects only, and LVEF > 35% (MI-I); 3) 67 pts with prior MI, fixed defects only, and LVEF < 35% (MI-II); 4) 24 pts without prior MI, LVEF > 45%, reversible 0schemie) defects, and oath documented CAD (ISCH). Resting LVEFs were calculated from gated SPECT perfusion scans. A L/[-I ratio was calculated from 30-40 min post-stress anterior planar projection images. Group n LVEFf+ISD) L/It(pvs.Normals) Normals 76 65+9 .32+.05 MM 75 44+13 .37+.08 (p=4xlO 4) MMI 67 30+15 .40+.+.09 (p<10 "6) ISCH 24 55+8 .37+.07 (p=2xlO "4) Thus, both in MI pts with resting dysfunction and no isehemia as well as in pts with normal resting function and stress-induced ischemia the L/H ratio was higher than in normal pts. The L/H ratio was higher in MI-II than MI-I pts (p=.03). In all groups L/H ratios for exercise versus pharrnacologie stress were nearly identical. We conclude that both stress-induced ischemia and the degree of resting LV dysfunction independently contribute to increased sestamibi lung uptake.

IN D I A S T O L I C A N D S Y S T O L I C P E R F O R M A N C E IN CHRONIC AORTIC REGURGITATION N. L e b o w i t z , M. Szulc, D. F i s h m a n , E. M. Herrold, J. S. Borer. Cornell Medical Center, N e w Y o r k , N Y , U S A

Experimentally, fibrosis and myocytolysis develop together in chronic aortic regurgitation(AR), suggesting that systolic (myocyte loss) and diastolic (fibrosis) dysfunction should occur simultaneously. Since exercise(ex) intolerance may result from systolic or diastolic dysfunction, symptoms(s×) should relate to their concurrent development. To test this hypothesis, 49 pts (18 NYHA class _>II [sxl, 3l asymptomatic[asy]) with severe chronic isolated AR were studied with rest(r) and ex radionuclide cineangiography. LV ejection fraction(EF) at r was lower in sx pts (47%) vs asy pts (55%, p<.05) while peak diastolic filling rates (PDFR) were similar (asx=2.4, sx=2.3,NS). However, during ex, PDFR and LVEF were reduced similarly in both groups (LVEFxasy =51% vs sx =38 % [25 % +], p < .01; PDFRx-asy =2.4 vs sx = 1.8 [25 % ,~ I,P < .02). Thus (1) systolic and diastolic dysfunction develop in parallel in AR; (2) both are importantly related to sx development, possibly parallelling development of myocytolysis and fibrosis.

99.4

99.6

A QUALITY CONTROL PROJECT IN NUCLEAR CARDIOLOGY. R.Campini*, R.GiubbinV,P.L.Pieri^for the Italian Group of Nuclear Cardiology - *Fondazione Maugeri Centro Medico di Veruno, °Spedali Civili Brescia, ^ Ospedale Bufalini Cesena

EFFECTS OF ct 1 BLOCKADE ON MYOCARDb-kL BLOOD FLOW IN PATIENTS WITH CARDIAC SYNDROME X. SD Rosen, R Lorenzoni, *J-C Kaski & PG Camici. MRCCSC/RPMS, ttammersmith & *St George's Hospitals, London, UK.

A survey of the actual situation in the country aimed to promote an improvement in homogeneity of the standard of interpretation of the scintigraphic studies was developed on the basis of a common feeling that satisfactory quality of acquisition procedure was achieved, while a wide variability of processing, reading and reporting was still persisting. 49 nuclear labs equipped with instruments from 6 different manufactories joined the project. In a first phase 2 studies including planar thallium stress/rest scintigrams, clinical history, EKG were sent to participants, with Elscint,GE or Sopha cameras. Each centre was asked to produce a report according to the lab standard. 22 centres sent back their results, The analysis of the available reports took into account the general fashion of the clinical report and specific nuclear cardiology contents. 73% of the centres reported the stress testing; 27% included EKG, 86% scintigraphic images, 45% evaluated and 27% quantified the lung uptake, 86% the ventricular volumes, 54% performed a quantitative analysis and 18% referred perfusion defects to specific vascular territories. 25% variability was observed concerning the definition of normal-abnormal studies, maybe related to the absence of "easy to catch" abnormalities in these studies. Ongoing studies will provide further experience.

The chest pain in cardiac syndrome X [SX, angina, ischaemic-like stress electrocardiogram (ECG) and a normal coronary arteriogram], has been thought to be due to coronary mierovaseular constriction, possibly adrenergically mediated. A preliminary study in SX patients treated with o~1 blockade showed increased myocardial blood flow (MBF, ml/mirug) after i.v. dip~cidamole "(D). Itowever, a similar increase has been reportedin normals. Thereafter,we investigated MBF in SX, at rest (R) andafterD (0.56mg/kg over 4 rain), using positron emission tomography (pEr) with H2JsO and fouhd it to be comparable to tlaat of matched controls. We have now proceeded to measure MBF (R&D) in 28 SX (I7 female, age 55±6), half (,4.) randomisedto l0 days' treatment with doxazosin (Dox), 2rag/day p.o. and half 03) to placebo. Heven normal subjects (C, 5 female, age 55±10) were also studied after Dox. Coronary vasodilator reserve (CVR) was derived as MBF(D)/MBF(Rcst); MBF(Rest) was corrected for resting heart rate (HR) x systolic blood pressure (SBP) as: MBF(Cor)= MBF(Rest)xl04/(H1LxSBP). CVR corrected (Cot) was cal culated as CVR(Cor)= MBF(D)tMBF(Cor). R e s u l t s :

MBF(~) MBF(D~ CVR

!I

MB~'(Co~I CRV(CoO

A 1.13±0.27 2.99±1.31 2.66_+0.98 1.43±0.35 2.14±0.92 1.20±0,26 3.65_+I.13 3.05±0.81 1.44±0.38 2.644-0.85 1.15±0.22 3.50±0.75 3.09±0,56 1.52±0.22 2.32±0.56 NS NS NS NS NS In conclusion, the effect of ct 1 blockade with doxazosin on MBF is comparable between SX patients and normal controls.

S 112

Abstracts Wednesday afternoon, April 9, 1997

99,7

99.9

R I G H T ATRIAL SESTAMIBI UPTAKE IN PATIENTS WITH PAROXYSMAL SUPRAVENTRICULAR ARRHYTHMIAS C.Marcassa, M.Galli, R.Campini, F.Fringuelli. S. Maugeri Foundation IRCCS, Veruno, Italy.

EVALUATION OF WOLFF- PARKINSON-WHITE (WPW) PATIENTS BEFORE AND AFTER RADIOFREQUENCY (RF) ABLATION OF ACCESSORY PATHWAYS. L. Bontemps, H. Ben Brahim. T. Kralem, P. Chevalier, G. Kirkorian, P. Touboul, R. Itti. Cardiovascular Hospital, Lyon, France.

Paroxysmal supraventricular tachiarrhythmias (PSVA: supraventricular tachicardia and, occasionally, atrial fibrillation), have been observed in patients with no organic heart disease. In a consecutive cohort of 216 patients referred for a stress-rest sestamibi SPECT for the evaluation of suspected or known C A D and without signs of cardiac disease, other than CAD, at clinical and t r a n s t h o r a c i c 2 D - E C H O , history of P S V A was documented in 14 (6%) patients. A clear right atrial sestamibi uptake was observed in 20/216 patients (9%). At ECG-gated images, the right atrial tracer uptake was diffuse in 12 patients (60%) and localized in the remaining 8 (40%), Out of 20 patients with abnormal right atrial uptake, 10 (50%) had history of P S V A (atrial fibrillation in 7 patients, SV tachicardia in 3 patients); the right atrial uptake was diffuse in 7/10. Conversely, out of 202 patients without PSVA, only 10 (5%) had right atrial sestamibi uptake (p<0.001) (RR for PSVA of right atrial tracer uptake =24.5, (21 6.5-91.9). Some structural abnormality of the atrial wall (otherwise undetected at conventional noninvasive screening) may be responsible for the unusual right atrial tracer uptake. Such structural abnormalities may be the trigger, in some cases, of "lone" supraventricular arrhythmias.

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Journal of Nuclear Cardiology January/February 1997, Part 2

In order to demonstrate the effects of radiofmqueacy (RF) ablation of accessory pathways in WPW patients (pts) on the left (LV) and fight (RV) ejection fractions (EF) and on Fourier phase variables, a group of 40 consecutive patients has been evaluated before and after RF. According to electrophyslology, the patients have been classified into : right sidedWPW = 13 pts and left sided WPW = 27 pts. From gated blood pool SPECT, perfumed shortly before and after RF, left a~l fight ejection fractions have been measured as well as mean phases (MP, expressed in degrees) and phase standaxd deviations (PSD). LVEF RVEF left WPW before RF afterRF fight WPW before RF afterRF

LVMP

RVMP LVPSD RVPSD

62+/-8 36+/-7 141+/-17 144+/-19 13+/-3 21+/-9 64+/-7 38+•-9 143+/-15 141+1-14 13+/-2 21+/-8 60+/-8 36+/-10 145+/-21 132+/-18 15+/-6 27+/-12 59+1-8 40+/-9 144+/-18 143+/-12 12+/-3 19+/-4

Results indicate that RF preserves or slightly improves cardiac function, in right sided WPW, phase analysis clearly demonslrates the disappearance of preexcitation associated with a significant reduction of phase dispersion, ie conlraction heterogeneity. In left WPW, the phase differences are smaller, specially in postero-iateral locations of the pathways, and pre and post RF changes are more difficult to quantify.

99.8

99.10

MENTAL-STRESS INDUCED LEFT VENTRICULAR DYSFUNCTION: REPRODUCIBILITYWITH DIFFERENT MENTAL STRESSORS Diwakar dain, Matthew Burg, Robert Soufer, Barry L Zaret. Yale University, New Haven CT

A B N O R M A L M Y O C A R D I A L 1-123-MIBG U P T A K E IN PATIENTS

Mental Stress (MS) provokes myocardial ischemia in patients (pts) with coronary artery disease (CAD). A number of different tasks are used to induce MS. The relative potency, reproducibility & agreement between different MS tasks are not known. Twenty CAD pts with exercise induced ischemia underwent a battery of MS tests [Mental Arithmetic (MA), Color Stoop test (CS) and Anger Recall (AR)] while undergoing continuous ambulatory left ventricular (LV) function monitoring. Ten Lotsdeveloped LV Dysfunction (Dys) (_>5%fall in LVEF) with _>1stressor(s). These 10 pts underwent second MS 4-8 weeks later with no change in medication or clinical status. The frequency of LV Dys on the first (#1) and second occasion (#2), reproducibility of the responses and increase in HR (AHR) and systolic blood pressure (ASBP) in these 10 patients were: MA LVDys#1 70% LVDys#2 60% Reproducibility 50%

CS62% 75% 62%

AR ;:1test AHR ASBP 90% 100% +7+5 +27+10 80% 90% +7±4 +24__.10 90% 90%

In CAD pts with MS induced LV Dys, AR produces LV Dys with highest frequency (90%) & is most reproducible (90%). MA & CS induce LV Dys less frequently and are less reproducible. Overall, on retesting 90% of the pts had reproducible response with at least I stressor. HR and SBP changes were not different between two studies. Response to repeat MA & CS may be influenced by conditioning. In contrast, response to AR remains highly reproducible since it uses a different kind of life situation to elicit anger. Protocols evaluating treatment effects should employ either AR alone or a battery of MS tasks.

WITH ACQUIRED LONG QT SYNDROME (LQTS). L. Bontemps, P. Chevalier, A. Dacosta, E. Bonnefoy, G. Kirkorian, P. Touboul, R. Itti. Cardiovascular Hospital, Lyon, France. Acquired LQTS may be a variant of inherited LQTS, and therefore could be associated with cardiac sympathetic innervation disorders, as it has been previously demonstrated in congenital LQTS, using non invasive imaging. The purpose of this study was to evaluate semiquantitatively the pattern of myocardial uptake of 1-123-MIBG in a group of patients with acquired LQTS. After exclusion of coronary artery disease using coronary angiography or thallium stress sciatigrnphy, seven patients (aged 70 +1'- 8 years) have been selected for planar MIBG scintigmphy acquired in anterior projection four hours after tracer injection. Five healthy volunteers were the reference. Regional MIBG uptake was expressed in counts per pixel in several regions of interest and heart/mediastinal ratios w~e calculated for the most active part of the myocardium (A1), the less active region in cases where a localizeddefect was present (A2) and the total left ventricular area (A3). Compared to normals, the results are : AI A2 A3

1.53 +/- 0.23 1.30 +I- 0.10 1.39 +/- 0.15

vs

1.97 +/- 0.24

(p < 0,05)

vs

1.98 +/- 0.17

(p < 0.05)

From these results it can be considered that an abnormal cardiac sympathetic innervation can be documented in patients with acquired LQTS on the basis of 1-123-MIBG seintigraphy.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday afternoon, April 9, 1997

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100.3

100.1 ARAZOLOL AS A RADIOLIGAND FOR THE G OF CARDIAC [3-ADRENOCEPTORS USING

SPECT. E.A. Dubois, G.A.Somsen, J.C. van den Bos, A.G.M. Janssen, M. Pfaffendorf, P.A. van Zwieten, E.A. van Royen. Academic Medical Centre, Amsterdam, The Netherlands.

In patients with heart failure sympathetic activity is increased and cardiac [3-adrenoceptors (IS-AR) are downregula.ted. Reduction ot this neurohormonal activation is related to improved prognosis. Therefore, it would be of clinical importance to measure cardiac [3-ARdensity non-invasively. The present study was designedto developa radioligand to i~age IS-ARusing SPECT; (SI-4-(3-(1,1-Dimethyl-3-iodoztz-propenylammo)-z-nyoroxypropoxy)carnazole (CYBL8E), an iodinated derivative of carazolol, was evaluated both in vitro and in vivo. Using homo~enates of cardiac left ventricular tissue (LV) of male New ~ealand White rabbits, the Ki-value of this compound for the receptor was determined at 0.31 _+ 0.03 nM, versus 0.76 + 0.10 for CGP12177 (mean + S.E.M. n=3-5). Subsequently, the biodistribution and specific ~inding in vivo was studied. Rabbits received 50 g Ci CYBL8E (specific .activity >. 5000 Ci/mmol), intravenously. Animals were killed at several time points after injection. Radioactivity levels were measured in Iung (L) and LV. In additional experiments animals were pretreated with 0.1 gmol of the antagonists ICIl18,551, atenolol, CGP 12177,. o.r -(-)propranolol,. 1.0 n)inu~sp..ri£r t£ the administration o~ tl~e raaio'ligand. AtenomJ, t~ut-~z~H and -(-)propranolol significantly reduced LV uptake by 36%, 64%, and 59%, respectively. ICI118,551 slightly increased Ly.uptake. ICI.118,551, atenolol,. C,GP12177, and(-)propranoml s~gnincantly recluced L uptake ny 43%, 64%, 66%, and 55%, respectively. These data demonstrate that CYBL8E may be a suitable SPECT radioligand.

EVALUATION OF FLOW AND METABOLISM IN RAT HEART USING "PINHOLE" SPECT SYSTEM T.Hirai,R.Nohara,R.Hosokawa,Y.Fujibayasi,M.Tanaka, S.Sasayama. Kyoto University Hospital, Kyoto, Japan Pinhole SPECT is a new system to evaluate the regional properties of radiopharmaceuticals in small laboratory animal in vivo. In order to visualize the myocardial flow and metabolism in rat heart, 2°1Tt(n=10) and ~23I-BMIPP (n=6) image was taken just before and 3 weeks after LAD occlusion/reperfusion. Image was reconstructed by filtered backprojection algorithm after fan-beam-to-parallel-beam data conversion. Then the percentage of 2°~T1-SPECTinfarct size (SI) and the defect score(DS) were assessed, and compared to the histological infarct size(HI) (A.D. Weiss, Circulation 1977;55:66-73). Both SI and DS correlated well with HI (r=0.97 in and 0.74 in , respectively). 80[ ~ 40,

60

%S140 x-12.8 20[ / I (r = 0.97) 20 40 6070 %HI

DS

3ot

- / ,,:

•

20[ .~'~oye=O.62x_ 4.26 I0 ~ . l . "f (r = 0.74) 20 40 60 70 %HI

Abnormal region of mI-BMIPP was larger than that of 2°lTI in reperfused rat heart(mismatch), which indicates the rectaboric insulance at the marginal area of the infarction, Thus, serial SPECT using pinhole collimators permits estimates of myocardial flow and metabolism non-i'nvasively in vivo.

100.2

100.4

INTRAINDIVIDUAL COMPARISON OF 3(R)BMIPP AND 3(S)-BMIPP ISOMERS IN HUMANS. V Caveliers, PR Franken, FF Knapp Jr, FT Mokler, Q Lin, H Luo, A Bossuyt. Free University Brussels (AZ VUB), Belgium; Oak Ridge Nat. Lab., TN, USA.

BACK DIFFUSION OF BMIPP PLAYS AN IMPORTANT ROLE IN PERFUSION/METABOLISM MISMATCH ON SPECT IMAGES WITH ISCHEMIA R Hosokawa, R Nohara, Y Fujibayashi, T Hata, M Fujita, S Sasayama Kyoto University Hospital, Kyoto, JAPAN

Racemic (3-R,S) 1-123 BMIPP is used at several centers for myocardial SPECT. Recent animal studies have shown that 3(R)-BMIPP has a more favourable biodistribution than the 3(S)-isomer (higher myocardial and lower hepatic uptake). To evaluate their respective distribution in humans, each 1-123 labeled isomer was injected at rest, on 2 separate days, in six patients with myocardial infarction. Dual-head total body scanning was performed 20 rain and 3 hrs after injection. Myocardial SPECT was obtained 60 min after injection. Heart uptake averaged (% injected dose + sd) 2.60 +0.49 vs 2.48+0.47 at 30 rain, and 2.23+0.29 vs 2.04+0.36 at 3 hrs, for the R- and S- isomers, resp (p=NS). Liver uptake averaged 7.59+1.22 vs 7.53 +0.79 at 20 min, and 5.33_+0.64 vs 5.43+0.66 at 3 hrs, resp (p=NS). SPECT showed no difference in the distribution of the two isomers between normal and infarcted tissue. We conclude that there is no difference in the heart - liver distribution of the 3(R)- and 3(S)-BMIPP isomers in humans.

1-123 BMIPP is a novel tracer for fatty acids metabolism with unique property of perfusion/metabolism mismatch on SPECT images in patients with ischemia(IS). However, the reason is still unclear. Metabolites in effiux and tissue analytical-studies were performed. Using open-chest dogs, LAD was occluded for 30 min with following reperfusion(RP). Blood samplings from artery and great cardiac vein (6 dogs), or serial biopsies from LAD region (5 dogs) were performed, and compared to the control (5 dogs each). HPLC and TLC techniques were introduced. Extraction (30 sec) and retention (30 min) of BMIPP were unchanged, however, early washout (8 min) increased (50% to 61%, p<.05) on IS. The metabolites from the myocardium consisted of BMIPP back diffusion (BD), c~, intermediate, and full oxidized metabolites. Among these, BD increased (25.1% to 34.7%, p<.05) especially in the early phase on IS. In tissue, BMIPP and (z oxidized metabolite significantly decreased in the early phase with IS (T=I min, 23.7% to 14.5%, p<.05). Myocardial blood flow recovered after 20 min of RP. These results indicate the increased BD and decreased tissue BMIPP might play an important role in perfusion / metabolism mismatch.

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Abstracts Wednesday afternoon, April 9, 1997

1 00.5

100.7

IMPROVED IMMUNOASSAY FOR THE DETECTION OF INTRACELLULAR CARDIAC ANTIGEN: MODEL ASSAY USING BISPECIFIC ANTI-MYOSIN, ANTI-DTPA ANTIBODY

EFFECTS OF POTASSIUM CHANNEL OPENER ON THE KINETICS OF THALLIUM-201 IN IN-VITRO AND IN-VIVO. J Lee, EJ Kim, BC Alan, SC Chae, JH Ha, KB Lee. Kyungpook National University Hospital, Taegu, Korea

B.A. Khaw, L. Wu, and J. Narula. Northeastern University, Boston, MA, USA. We have previously demonstrated that a polyDTPA-polylysine polymer coupled to antimyosin (AM) antibody (Ab) permitted incorporation of very high specific radioactivity on very small concentration of Ab. This modification of Ab helps to substantially enhance the target image quality. To evaluate if this strategy could be exploited to improve the sensitivity of in vitro immunoassay, a bispecific antibody (BAb) was developed. Monoclonal AMAb (R11D10) was covalenUy linked to Ab specific for DTPA (4G41D5). For ELISA, the detection probe (DP) consisted of polyDTPA-polylysine (28:1 molar ratio) covalently linked to horse-radish peroxidase (HRP, 6-7 moles/mole polylysine)(DP-HRP). Serial dilution of rat cardiac myosin (0.0001 to 10 p.g/ml) coated to microtiter wells, were incubated with a constant BAb concentration (0.1 ~tg/ml). The immune complexes were recognized by goat anti-murine IgGHRP, or DP-HRP followed by the dinitrobenzedine. PolyDTPApolylysine polymer was labeled with 1111n as DP for radioimmunoassay. The affinity and sensitivity of the BAb were 2.5x101° IJM and 0.001 pg/ml, respectively which were about 100-fold greater than those of the RI 1D10 (5x108 and 0.1 I~g/ml). The maximum signal intensity was approximately 2-fold greater even at 100-fold less BAb. This BAb technology should enable development of other in vitro assays with enhanced sensitivity for the detection of myocardial necrosis.

Y

P M A P R I L

Potassium channel opener (K-opener) opens membrane ATP-sensitive K+-channel and induces an increase in Kefflux from cell. To evaluate the effect of pinacidil(a potent K-opener) on TI-20I biokinetics, we have performed uptake/washout studies in cultured myocyte and mice biodistribution study. Pinacidil was co-incubated with TI-20I in HBSS buffer to evaluate its effect on cellular uptake, or challenged to myocyte preparations preincubated with TI-201 for washout study. Pinacidil was injected into mice simultaneously or at 10 min after TI injection, and organ uptake was measured. Co-incubation of pinacidil with TI-201 resulted in a decrease in T1 uptake into myocytes by 1.6 to 2.5 times. Pinacidil injection resulted in mild decreases in blood and liver uptake in mice, but renal and heart uptake was mildly decreased in a dose dependent manner. These results suggest that the pinacidil alters TI kinetics and may potentially affect the interpretation of TI-201 myocardial imaging.

100.6

100.8

THREE MONOCLONAL ANTIMYOSIN ANTIBODIES: SAME SPECIFICITY, DIFFERENT AFFINITIES ON IN VlVO MYOCARDIAL INFARCT IMAGING

CARDIAC SYMPATHETIC ACTIVITY IN HEART FAILURE; A COMPARISON BETWEEN CARDIAC MIBG SCINTIGRAPHY AND HEART RATE VARIABILITY. G.A. Somsen, B.M. Szab6, P.A.R. de Milliano, A de Groot, D.J. van Veldhuisen, E.A. van Royen. Academic Medical Centre, Amsterdam, the Netherlands.

B.A. Khaw, A. Petrov, and J. Narula. Northeastern University and Massachusetts General Hospital, Boston, MA., USA.

W E D N E S D A

Journal of Nuclear Cardiology January/February 1997, Part 2

To determine whether specificity is the sole determinant of the efficacy of the in vivo use of monoclonal antibodies (MAb) for gamma imaging of acute myocardial infarction, 3 MAb specific for human cardiac myosin with different affinities were studied. Fab fragments of R11D10 (0.5-1x10g L/mole), 2G42D7 (0.5x 9, 10 ] and 3H3 (5x106) were radioiabeled with either 1-123, 1-125 or In-111 and injected into dogs with reperfused acute myocardial infarction. Serial left lateral gamma images were performed for 5 h. The infarct to blood activity (I/B) ratios were determined from the 5 h left lateral images by computer planimetry, liB for R11D10 (1.51+0.16 mean+SD, n =13) was not significantly different from that of 2G42D7 (1.50+0.27, n = 13, p = 0.91). liB ratios of R11D10 and 2G42D7 were significantly higher than the liB ratio of 3H3 (0.85+0.12, n = 3, p = 0.0001 and 0.001, respectively). The control I/B ratio of a non-specific Fab in canine reperfused infarct was 0.75. Infarcts were visualized by 5 h with either R11D10 or 2G42D7, but not with 3H3 nor non-specific MAb. The low affinity 3H3 which has specificity for cardiac myosin in vitro was unable to delineate the infarct in vivo. Therefore, although specificity is a necessary condition, sufficiently high affinity of the antibody is essential for in vivo detection of acute MI by gamma imaging.

Introduction: In patients with chronic heart failure (CHF)

increased sympathetic activity is related to mortality. Therefore, non-invasive methods to detemaine cardiac sympathetic activity may have important clinical applications. 123I-metaiodobenzylguanidine (MIBG) scintigraphy can be used to determine cardiac sympathetic neuronal function. Whether this technique p r o v i d e s 0.6information on cardiac sympathetic activity, as can be measured by heart ~ t / " rate variability (HRV) is unknown. ~ 0.4Methods: In 10 CHF patients, after injection of 185 MBq MIBG, cardiac ~" washout (from lh to 3h) and uptake .~ 0.2(after 4h) was determined. HRV during 24h ECG monitoring was calculated. The normalized low ~ o.o. frequency power calculated from ,o o 10 20 so HRV power spectrum was used as a CardiacMlBGwashout(%) measure of sympathetic activity. Results: MIBG washout correlated significantly with the normalized low frequaney power (r=0.7, p=0.02) (fig.) while MIBG uptake at 4h did not correlate with this parameter. Conclusion: Cardiac MIBG washout is a sensitive indicator of cardiac sympathetic activity in CHF patients and may therefore have clinical value as a prognostic marker in these patients.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday afternoon, April 9, 1997

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QUANTIFICATION OF MYOCARDIAL BLOOD FLOW WITH CONTRAST ECHOCARDIOGRAPHY USING VENOUS INFUSION OF CONTRAST

COMPARISON OF Tc-99 TETROFOSMIN AND 511 keV COLLIMATED MYOCARDIAL PERFUSION SPECT -- THE EFFECT OF COLLIMATOR RESPONSE CORRECTION. S. Miller, P. Maniawski, Picker Int. Cleveland OH. USA., L. Zeng Univ. of Utah USA, E. Krenning Univ. Hospital, Rotterdam, The Netherlands.

S o r o o s h Firoozan, K e v i n Wei, A n a n d a J a y a w e e r a , D a n n y

Skyba, Norman C. Goodman, Sanjiv KauL University of Virginia, Charlottesville, VA, USA We hypothesized that ultrasound-induced microbubble destruction can be used for quantifying myocardial perfusion during venous administration of microbubbles. If microbubbles are administered as a continuous infusion, then destroying them in the myocardium and measuring their myocardial reappearance rate will provide a measure of mean myocardial microbubble velocity. In 6 dogs the left anterior descending coronary artery was cannulated and its flow was set at 5-6 different rates using a roller-pump. The ultrasound pulsing interval was randomly varied at each flow rate. Background-subtracted video intensity was plotted against the pulsing interval and the relation was fit to an exponential function y=A( 1- e 4~" ), where y is video intensity at a pulsing interval t, A is the peak video intensity, and B is the rate constant that determines the initial rate of rise of video intensity. An excellent correlation was found between coronary blood flow and B (average r=0.91, n=33), It is concluded that myocardial perfusion can be quantified during venous infusion of contrast with a novel approach that utilizes the destruction ofmicrobubbles with ultrasound.

We demonstrate a novel iterative reconstruction technique which reduces the collimator blur associated with 511-keV ultrahigh energy parallel (UHEP) hole collimation and yields SPECT results comparable to that of non-blur compensated low energyhigh resolution parallel (LEHRP) hole collimation. Prior to this, the spatial resolution of collimated 511 keV gamma photon cardiac SPECT has been questionable. Patient studies were acquired on a Picker P3000 utilizing a standard stress/rest low energy (Tc-99) tetrofosmin protocol. The studies were reconstructed with filtered backprojection (FB), and reformatted to display the short, vertical long, and horizontal long axes. Following this study, the same patients were injected with FDG (F-18) and imaged using UHEP collimators. These studies were processed with FB ,and again with a modified OS-EM reconstruction algorithm. Distance dependent blur due to the collimator is modeled within the OS-EM algorithm and is iteratively removed in 3-D. These blur compensated images illustrate a dramatic improvement in spatial resolution over the uncon'ected images and compare favorably with their non-blur con'ected low energy counterparts. These results demonstrate significantly improved diagnostic quality for 511 keV collimated SPECT images.

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MYOCARDIAL VIABILITY BY INTRACORONARY INJECTION: PRELIMINARY RESULTS

C.Corbelli, F.Fallani, F.Tartagni, M.Levorato, F.Grigioni, A.Marzocchi, C.Marozzini, S.Fanti, P.L.Guidalotti, M.Dondi, N.Monetti. Depts of Nuclear Medicine, Ospadale par gli Infermi, Faenza and Polidinico S.Orsola-Malpighi, Bologna, Italia. Rest-redistdbuUon 201-TI imaging after i.v, injection is widely accepted to asess myocardial viability. However, because of its relatively low myocardial uptake, heart-to-background (H/BK) ratio of TI-201 is low. To assess myocardial viability, we compared standard TI-201 rest-redistribution 8PECT after i.v. (IV) injection (120 MLx:I) and TI-201 8PECT after intracoronary (1(3) injection (8-10 Mix]), performed during diagnostic angiography when TI-201 was slowly delivered into the left main (8 pts), right coronary (4 pts) or beth vessels ( 3 pts). No adverse reactions were observed after IC injection and image quality was excellent in all cases. Blood and 24 hrs udne samples were obtained to evaluate circulating and urinary activity, H/BK ratio was 7.3+1.5 and 1.5+_0.2, after IC and IV injection, respactively (p<0.001). In 1 patient myocardial uptake was detected in akinetic segments with IC but not IV injection. In the remaining cases, we failed to see any difference between the two studies. Serum and 24 hrs udne radioactivity was by far lower with IC than with IV route (23+_15 vs 292_+35 Bqlcc and 165+_25 vs 2231+57, p<0.001). In conclusion, IC-TI-201 injection may safely and effectively performed during diagnostic coronary angiography. Radiation exposure and images quality indicate that IC route may represent a valid approach for the assessment of myocardial viability in patients undergoing coronary angiography.

SIMULTANEOUS PERFUSION AND METABOLIC IMAGING USING DYNAMIC CARDIAC SPECT. G. Gullberg, E. DiBella, S. Ross. University of Utah, Salt Lake City, UT, USA. A new and exciting area of nuclear cardiology is the simultaneous imaging of perfusion (with ~Te-sestamibi) and metabolism (with 18FDG) using SPECT. Dynamic cardiac SPECT may allow for the simultaneous measure of perfusion and metabolism with the injection of only one tracer. Dynamic three-dlmensional reconstructions are obtained from serial tomographic projection sets of the 3D distribution with a temporal resolution as fine as 5 seconds. From the reconstructed data, compartment modeling techniques are used to estimate kinetic parameters reflecting the changing distribution of the radiopharmaceutical through the blood and tissue of regions in the heart. Three models will be presented: a one compartment model for the perfusion of a T e teboroxime, a two compartment model that models the distribution and metabolism of 18FDG, and a three-compartment model that models the distribution and metabolism of the fatty acid 1~l-labelled iodophenylpentadecanoic acid (IPPA). Each model will be compared as to its feasibility to measure simultaneously myocardial tissue perfusion and metabolism.

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100.13 COST-EFFECTIVE PREPARATION OF 99mTcTETROFOSMIN BY REFORMULATION AND FRACTIONATION OF MYOVIEW® KIT INTO MULTIDOSE COLD KITS. Ouhayoun, E.; Leconte, V.;. Coca, F.; Bastir, D.; Coulais, Y.; Esquerrr, J.P. and Tafani, J.A.M. Service central de Mrdecine Nuclraire. Hrpital Purpan. Toulouse. France. 99mTc-Tetrofosminis a new powerful radioligand especially used for myocardial perfusion SPECT imaging. In order to use the expensive Myoview® kit in a more costeffective manner, we developped an original splitting method. Using aseptic techniques, the lyophilized components of the original kit were dissolved in 3,5 ml of 20 ~g/ml N2-purged SnCI2 in bicarbonate buffer solution (pH 8). The kit was then splitted into 0,5 ml aliqnots in six separate vials, overlayed with nitrogen. The fmctionated kits were frozen at -20°C during a four weeks evaluation period. Each of them was reconstituted with 1,5-2,5 ml of 100-250 mCi (3,70-9,25 GBq) 99mTcfor a multi-dose use. The RCP of the fractionated kits was determined by two thin layer chromatography systems on silica gel plates using acetone/dichloromethane (35/65,v/v) and methanol/H20/TFA (70/30/0,1,v/v) as mobile phases. Over the four weeks period, the average RCP of fractionated 99mTc-Tetrofosmin preparations was maintained at 96,4+2,5% (n=12) and all bacteriological controls were negative. Moreover, image quality with fraetionated kits was equivalent to original kit.

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100.15 3D PERFUSION STUDIES USING A MOBILE GAMMA CAMERA BASED ON ECTOMOGRAPHY S.Dale, D.Bone, L-A Brodin, H.Elmqvist, M.Holmberg, C.Lindstrrm, M.Persson, T.Ribbe, L. Jorfeldt Karolinska Institute, Stockholm, Sweden A mobile tomographic gamma camera has been developed to enable three-dimensionai perfusion studies in the emergency room and in the intensive care environment. The system, Cardiotom, is based on the limited view angle method Ectomography and comprises a modem detector head equipped with a rotating slant hole collimator, and specially developed hardware and sot~ware for data acquisition, processing and display. The mobile system is PCbased running Windows 3.1 and is totally self-contained. The collimator has different projection directions, so that several simultaneous projections are obtained. The acquisition time is reduced with a factor equal to the number of projection directions; with a 4 segment collimator, the acquisition time is typically 6 rain for a myocardial perfusion study using Te-99m sestamibi. System volume resolution depends on the collimator slant angle and increases from 0.8 em3 at 5 cm to 7.2 cm3 at 20 cm for a slant angle o f 40 degrees. The system, with a total weight of 350 kg, is currently in use at the Karolinska hospital for a blind comparative study with SPECT and for infarction treatment assessment.

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PERFORMANCE COMPAR/SON ON A DIGITAL GAMMA CAMERA MODIFIED FOR POSITRON IMAGING: 3/8 INCH VS 1/2 INCH CRYSTAL T. Hill, D. Wagenaar, Beth Israel-Deaconess Medical Center, Harvard Medical School, Boston, USA

IMPROVED NORMAL DISTRIBUTIONS IN ATTENUATION CORRECTED TC-99M-SESTAMIBI CARDIAC SPECT WITH GD-153 TRANSMISSION SCANNING AND DOWNSCATTER CORRECTION SJ Cullom, MW Groch, WK Braymer, J Ye, SM Spies and RC Hendel, Emory University, Atlanta GA, U.S.A. Attenuation correction (AC) of Tc-99m-sestamibi (MIBI) SPECT using simultaneous Gd-153 line source scanning (SC) significantly improves the specificity of cardiac SPECT. However, attenuation map errors may result from downscatter ( D S ) o f Tc-99m photons into the Gd-153 transmission window leading to suboptimal attenuation correction. A DS compensation algorithm we previously described and evaluated in phantoms was evaluated in 20 individuals (10M,10F) with less than 5% pretest likelihood of coronary artery disease. Stress MIBI studies acquired with SC were reconstructed with FBP only, Maximum Likelihood (ML) with AC (VantageTM,ADAC Labs Milpitas, CA) and ML with AC and DS correction (DSC). Anterior/inferior (A/l), septal/lateral (S/L)wall ratios and % maximal nonuniformity between regions (NU) were extracted from a 9 region segmentation of the LV polar map. Males Females Method %NU A/I S/L %NU A/I S/L FBP 34 1.22 0.81 22 1.08 0.93 AC 24 1.07 0.84 16 1.07 0.93 ACw/DSC 15 1 . 0 1 0.94 12 1.02 0.98 Downscatter compensation provides additional improvement in the uniformity of MIBI distributions in both male and female low-likelihood patients. Further evaluation is ongoing to establish the diagnostic accuracy of this method and the validity of gender-independent normal files.

Cardiac viability studies using F-18 Huorodeoxyglucose (FDG) have become widely available with the use of gamma cameras modified with high energy collimators for positron imaging. The modifications of the fast generation camera systems were focused around the collimator. The second generation cameras are now including modifications such as changing the crystal thickness to improve the sensitivity of the imaging device. We compared performance measurements on a dual headed digital gamma camera with a 3/8 inch crystal and a modified version with 1/2 inch crystal. The sensitivity for 511 key improved by approximately 30%. Contribution from septal penetration in the sensitivity measuremeut were evaluated. Intrinsic spatial resolution was degraded to 3.4mm FWHM at 140 key from 2.7mm. Lesion visibility data for 511 key photons have been acquired for both crystals and gain in sensitivity enhanced lesion detection. Improvements in digital gamma camera design with thicker crystals can improve system performance for 511 key imaging without compromising its performance as a general purpose nuclear medicine gamma camera.

Journal of Nuclear Cardiology Volume 4, Number l, Part 2

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EFFECT OF MISALIGNMENT BETWEEN TRANSMISSION AND EMISSION SCANS ON ATTENUATIONCORRECTED SPECT I. Matsunari, G. B6ning, S. Ziegler, S. Nekolla, J, I. Kosa, E. Ficaro, M. Schwaiger. Technische Universitdt Miinchen, Germany

CLINICAL TOOL FOR AUTOMATED QUANTIFICATION OF MYOCARDIAL PER.FUSION SPECT.

Misalignment between transmission and emission scans on attenuation-corrected (AC) cardiac SPECT can introduce errors in measured activity. However, the severity of these errors has not yet been fully elucidated. The aim of this study was therefore to assess the effect of misalignment between transmission and emission scans on AC SPECT images. A cardiac phantom with technetium-99m was studied using a triple-head SPECT system (Multi-SPECT3, Siemens) with a collimated Am-241 line source and an off-set fan-beam collimator. The left ventticnlar myocardium was divided into 5 segments and the mean regional activities were calculated for each segment using a semiquantitative polar map approach. Misalignment between transmission and emission data was created by shiRing the emission projection data along the x, y or z axis. A shift between the transmission and emission data, regardless of its direction, produced a decrease or increase in relative regional activity in all 5 segments. A 1 pixel (7.1 mm) shift produced up to 15% change in relative regional activity. Thus, even a small misalignment between transmission and emission data can produce serious errors in measured activity, suggesting that geometrical precision is essential for accurate diagnosis in AC SPECT imaging.

PJ Slomka, P Radau, GA Hurwitz, JA Stephenson London Health Sciences Centre, London, Ontario, Canada. We developed PERFIT - a clinical tool for automated quantification of myocardial perfusion SPECT based on voxel comparisons of patient images to 3-dimensional normal templates. We devised a robust fitting scheme with automated masking of external activity before final fitting of size, position and angles. Templates were also adjusted to individual ventricles by the template erosion technique. The speed of algorithms is op: timised by specialised trilinear interpolation and other techniques; the processing time is 35 sec. on a SUN Ultrasparc. PERFIT was tested on Tc-99m sestamibi images of 120 angiographically correlated cases including normal, single, double and triple vessel disease, infarction, dilated ventricles, and left main artery stenosis. No manual angle adjustnnent was done. The algorithm was successful in 237 out of 240 (99%) stress and rest images as assessed visually by 2 observers. Manual masking of external activity allowed autonnated fitting of the remaining 3 studies. PERFIT outlined abnormal areas consistently with visual interpretation and with angiographic findings. PERFIT found defects in 2/29 normal patients (stenosis < 50%) and 90/91 abnormal patients (stenosis >=70%). PERFII~ is a robust and automated tool tbr aiding clinicians in interpretation of myocardial perfusion tomography and it can be applied to the whole spectrum of clinical images.

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INFLUENCE OF THE PARTIAL VOLUME EFFECT ON MYOCARDIAL 8PECT IMAGING. P.LRossini, E.Milan, R.Campini, OZoccarato, ATerzi, R.Giubbini. Nuclear MedicineDpts, Spedali CMli, Brescia& FondazioneSMaugeri, Veruno(No) Italy.

ASSESSMENT OF 1-125 BETA-METHY-BRANCHED FATTY ACID(BMIPP) AND THALLIUM(TI)-201 UPTAKE IN RATS WITH RIGHT VENTRICULAR FAILURE(RVF) BY USING AUTORADIOGRAPHY

The partial volume effect (PVE) affects scintigraphicimaging if the size of the object is below the resolution of the system. To evaluate the effects of the PVE on myocardial SPECT imaging we realized a phantom constituted of 2 cylinders eccentricallyfixed one inside the other.The chamber (A-B) between the two cylinders, simulatingthe LV wall, ranging 0-30 mm, was filled with a homogeneous solution of 99mTc. Nter lransaxialrecons~uctionof transversesections,the circumferential profile (cp) of the peak activity was displayed. Being the solution homogeneous the cp should be a slralght line unless the PVE. The use of 2 differentback-projectionfilters (BPF), Wiener ONR) (dumping factor=&& FWHM=11mm) and Butterworth (BT) (cut off freq=O.35, order=-5) was also taken into account. The relationship between wall thikness and recovered counts (% of the max) is summarizedin the followingtable: Thikness(mm) 30 2"/ 24 21 18 15 12 9 6 3 Wiener 92 96 98 100 100 97 92 78 63 39 Butterworth 98 100 99 97 92 84 77 62 49 31 The integralsof the recovered counts were significanttydifferent using WR and BT BPF(p<.O01). The max. count density was registered at 18mm ONR)and 27 mm(BT), respectively.Thus the PVE determines a significant,arlifactualcount loss when the size of the wall is below 1 cm, averaging6.5%h'nm between 3 and 9 ram, partiallydependingon BPF.

Y Nomura, K Matsumura, K Takeda, K Maruyama and T Nakagawa. Mie University School of Medicine, Mie, Japan In patients with pulmonary hypertension (PH), evaluation of RVF is important. We evaluated myocardial fatty acid metabolism using I-125 BMIPP and T1 perfusion in rats with RVF. S.D. rats were given a single subcutaneous injection of the toxin monocrotaline (40 mg/kg). At 3 weeks after treatment, mean puhnonary arterial pressure was significantly higher than that in age matched control rats (n=9). 1-125 BMIPP (0.37 MBq) was injected to the treated rats(n=6) and control(n=6) via the tail vein. TI-201 was injected to the the treated rats(n=3) and control (n=3). The hearts were excised at 30 rain after injection, weighed and counted. Autoradiography was performed using BMIPP and T1. The BM1PP uptake ratios of RV/LV and Septum/LV show as follows: Control : Treat BMIPP R V / L V 0.77--+0.08 ~<0.01 1.06±0.18 geplum/LV 0.82±0.07 ~<0.01 0.98±0.05 TI RVt'LV ]0.95±0.07 NS 0.97±0.10 I .~eptum/LV 19.964--0.03 0.95-----0.05 Autoradiography sho'ved decrease of BMIPP accumulation at RV and septum, in treated rats, but no decrease of T1 was shown. These results suggest that 1-123 BMIPP is a suitable tracer for evaluation of RVF in patients with PH.

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EFFECTS OF ATTENUATION CORRECTION ON CARDIAC EDGE DETECTION IN AN ANTHROPOMORPHIC PHANTOM Noera Ayaz, Lorraine Nott, Michael W. Campanella, Lynne L. Johnson. Rhode Island Hospital, Brown University, Providence, USA

HIGHER HEART UPTAKE OF 3(R)-BMIPP IN RATS BUT SIMILAR LIPID POOL DISTRIBUTION SUGGESTS DIFFERENCES IN ISOMER MEMBRANE TRANSPORT. 1F. F KnapD 1F. T. Mokler, 1Q. Lin 1H. Luo, 1A. L. Beets, 2j. Kropp, ~P. Franken, 1Oak Ridge Nat. Lab. (ORNL) , Oak Ridge~TN, 37831, USA, ZNucl. Med., Univ. Dresden, Germany, Free Univ. Hospital, Brussels, Belgium.

To investigate whether attenuation correction (AC) improves edge detection using threshold methods, an anthropomorphic torso phantom with cardiac insert (filled with Tc-99m) was imaged w and w/o AC; then a 5.7 ml mild (30%) defect was placed first in the anterior wall and then in the inferior wall and imaged using a dual detector camera with moving Gd-153 source. Ct profile analysis was performed on the reconstructed SA slices and slopes of the edges for both the myocardium and defects were calculated for the non-AC and AC slices. Slices were background subtracted and thresholds of 30% and 60% applied to non-AC and AC slices to size the myocardium. Slopes -AC +AC Anterior defect (cts/pixel) 11 14 Inferior defect (cts/pixel) 6.7 11 Myocardium (cts/pixel) 74 106 30% 60% diff. 30% 60% diff. -AC -AC +AC +AC Vol 171cc 100c 71cc 1 5 6 c c 97cc 59cc AC improves the resolution for defining defects and sizing the myocardium.

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•

i

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t

.

We have resolved and characterized 3(R)-BMIPP and 3(S)BMIPP. In rats (15-240 min), 3(R)- has 20-25 % higher heart uptake, 3(S)- has 10-12 % higher liver uptake, but other tissues are similar (J. Nucl. Med., 37, P6, 1996). Dual-label [1-125]-3(I=I)/[1-131]-3(S)-BMIPP studies have permitted an evaluation if differences in metabolism correlate with relative organ uptake. Folch extracts of heart, blood, liver, kidneys and lungs of rats (15, 60 and 180 rain) showed similar organic/aqueous distribution patterns for both radioisotopes and the same [I-125]/[I131] ratio of lipids by TLC and HPLC. HPLC analysis of free fatty acids and acids released by basic hydrolysis of purified triglycerides (30 min) showed identical HPLC profiles (C18 column) with several components. Acidhydrolyzed urine showed a single radioactive p(iodophenyl)acetic acid metabolite by HPLC. The results suggest that higher myocardial uptake of 3(R)-BMIPP may result from differences in transport into myocytes. • Research at ORNL supported by OHER/U.S. DOE

100.22

100.24

RHENIUM-188 ATTRACTIVE PROPERTIES FOR INTROVA$CULAR BRACHYTHERAPY FOR INHIBITION OF CORONARY ARTERY RESTENOSlS AFTER PTCA. 1F. F. (Russ) Knapp, Jr., iS. Guhlke, 1A. L Beets, 2H. Amols and 2J. Weinbercler, Nuclear Medicine Group, IORNL, Oak Ridge, TN and 2Columbia University, NY, NY.

IN VIVO STABILITY STUDIES OF THE NEUTRAL TECHNETIUM-99m NITRIDO DITHIOCARBAMATE COMPLEX TcN-NOET AFTER INJECTION IN RATS V.Comazzi, C. Guillaud, F. Joubert, R. Pasqualini. CIS bio international, Gif sur Yvette, France.

Costs associated with restenoses therapy after PCTA are estimated to be > $1 Billion in the U.S. Use of ionizing radiation offers potential as a simple, inexpensive, and effective tool to inhibit neointimal proliferation. Rhenium188 (tl/2 16.9 h, 2.1 MeV ,8] is obtained from decay of tungsten-188. (t112 69 d) " The W-188/Re-188 generator has a shelf-hfe of several months and Re-188 is eluted with 0.9% NaCI. Simple ion column methods have been developed to concentrate to > 100 mCi/mL. Balloon inflation with an NaCl solution of Re-188-perrhenate is an intriguing alternative for more uniform vascular dose distribution compared to radioactive wires. Perrhenate is excreted via the urinary bladder (tl/.2 10 h in humans) in the event of the worst case scenario of < 0.1% rupture incidence. Estimates indicate a target coronary artery region dose of 8.4 rad/mCi/min/mL, resulting in > 400 cGy dose for about 10 mCi Re-188 for 5 min. Studies are in progress in a swine model to evaluate the expected effectiveness of Re-188 for inhibition of restenosis. * Research at ORNL sponsored for OHER/U.S. DOE.

[Bis(N-ethoxy,N-ethyl dithiocarbamato)nitrido Technetium99m (V)], TcN-NOET is a new myocardial perfusion imaging agent which has displayed post-stress redistribution pattern like TI-201. The aim of this study was to determine whether chemical changes of TcN-NOET occur in vivo. This has been accomplished by HPLC analysis of radioactivity extracted from homogenized organs, after injection of the tracer in rats. We found that TcN-NOET remains chemically unchanged in heart, lungs and kidneys, whereas it is degraded in the liver. In this organ three principal metabolites have been identified. Only one metabolite, corresponding to the most hydrophilic HPLC component, has been found in the urine and bile. This metabolite, isolated by HPLC, was proved still to bear the (Tc-=N)2+ core present in the injected TcN-NOET complex. No pertechnetate as final degradation product was detected in the explored organs or in lood and urine. These results indicate that the uptake of TcN-NOET in the heart is not followed by chemical modifications of the tracer and that (Tc~N)2+ core in TeN dithiocarbamate complexes displays a remarkable chemical and biochemical inertness.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

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R E E V A L U A T I O N OF 360- AND 180-DEGREE ROTATION ACQUISITION WITH TL-201, TC-99M AND I- 123 LABELED MYOCARDIAL IMAGING AGENTS. K. Nakajima, J. Taki, W. Yamamoto, E. Hwang, N. Tonami, Kanazawa University Hospital, Kanazawa, Japan

ANTIMYOSIN IMAGING IN RADIO-INDUCED MUSCULAR NECROSIS. J-L. Albrrini, J-L. Lefaix, P. Bourguet. E Marquis Institute, Rennes, France.

Both 360 ° and 180° acquisition methods have been performed even after multidetector SPECT became available. The aim of this study is to evaluate the visual and quantitative difference of rotation angle using currently used radiopharrnaceuticals, i.e., T1-201, Tc-99m MIBI, 1-123 BMIPP and MIBG. Patients with normal, anterior defect and inferior defect were selected as typical models. Using 360 ° projection images, 180 ° data were reconstructed with starting angles of anterior, RAO 30°, RAO 6(7 and right lateral and quantified by polar map. Effect of lung and liver activity and elevated right hemidiaphragm were also evaluated. The results of simulation indicated that moderate defect with 50-60% of peak myocardial count was calculated up to 10 % higher in 360 ° rotation than in 180 ° rotation. In patients with a severe defect, the difference of up to 20% in defect count was observed. Specific polar map pattern was observed depending on the starting angle of 180 ° arc. Generally 180 ° collection created higher defect contrast, but even a difference of 30 ° in the starting angle could be a cause of quantitative distortion irrespective of radionuclide types. Whereas 360° methodology provided more stable results. We should notice the range of rotation for evaluating myocardial viability with quantitative analysis.

An experimental model of radio-induced muscular necrosis after localized irradiation was studied by scintigraphy using antimyosin antibody (AAb). Four rabbits were irradiated on the back (right muscle) by single doses o f 192Ir y rays of' 120 Gy (skin surface dose). Planar scintiscans (posterior views) were performed 48 hours after injection of AAb labelled with 18 MBq of rain (Myoscint ®) each week after irradiation during 2 months. Uptake in irradiated muscle is observed 5 weeks after irradiation, in according to results of histopathology and CT (muscular necrosis). Regions of interest (ROI) were determined around uptake on the irradiated muscle (right) and on the safe muscle (left) and permit to calculate a ratio [ROI right muscle / (ROI right muscle + ROI left muscle)], which is significantly higher (p<0.02) for irradiated animals than for safe animals. Antimyosin antibodies used in nuclear cardiology for ischemic heart disease, myocarditis or heart transplant rejection could be proposed to evaluate the importance of muscular necrosis after injuries (traumatisms, radiation accidents).

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100.40

THE SUPERIORITY OF T E C H N E T I U M I M A G I N G CHARACTERISTICS O V E R T H A L L I U M : M Y T H OR REALITY ?

CARDIOTOXICITY OF CHEMOTHERAPEUTIC A G E N T S IN CHILDREN. J. Kropp*, U. BOd~**, H.J. Biersacl~* , W.G. Franl(e Depts. of Nucl. Med. Univs. of Dresden* and Bonn*" and Dept. of Pediatrics Univ. of Bonn***; Germany We investigated 39 children (pts, mean age 8.3 years; range: 0.5-18.5 years) under therapy with anthracyclines (A) with 56 radionuclide ventriculographies (RNVG). EF, PFR and PER were evaluated. Other therapeutic modalities were: radiation therapyof the chest and cyclophosphamid therapy. We correlated our findings with chest x-ray, ECG, CK-MB, CK-MB/CK and the total dose of A. There was a trend to increasing values of EF and PER with age. There was no significant change of any RNVG-parameter up to 1380 rag/ m 2 but a trend of decreasing values with increasing dose. Additional radiation and/or cyclophosphamid showed no effect. We divided our pts into a low- and high-risk group. EF, PER, and PFR were sigfnificantly (p < 0.3) lower in the high risk group within four days after the last application of A. We conclude that RNVG is not a very suitable method to evaluate cardiotoxicity of A in children. But a subclinical toxic reaction early after application of the drugs could be substantiated with a reversible impaired function of the left ventricle. If other diagnostic modalities are taken into account low- and high-risk groups could be delineated.

G.McCurrach, G.Wright, S.Woldman, W.Martin, I.Hutton Dept. Nuclear Cardiology, Glasgow Royal Infirmary, Scotland This study was designed to assess the detection of simulated myocardial perfusion defects using both T1-201 and Tc-99m. Tc-99m compounds are of increasing interest for use in myocardial perfusion imaging, partly due to its claimed enhanced imaging characteristics. Typical counts from TI-201 and Tc-99m tetrofosmin clinical studies were obtained. In the study 212 images per radionuclide were acquired with each image being subdivided into 5 segments giving 1060 segments. Objects were defined by randomly choosing the position and size of defects in two phantoms of different wall thickness. Images were acquired at different depths and orientations, with scatter, for fixed times. Two observers reported each segment using a 5 point scale and then ROC analysis was carried out. The area under the curves plotted for each radionuclide were compared and Tc-99m was found to be larger by 0.047 (p=0.0011). The clinical significance of this is not yet clear. Measurements of system resolution with depth using both radionuclides showed a maximum improvement of 13%. In conclusion, similar resolution was obtained with both radionuclides with Tc-99m giving greater detectibility of lesions, possibly due to the increased count statistics.

I I

S120

Abstracts Wednesday afternoon, April 9, 1997

100.41

100.43

LEFT VENTRICULAR WALL MOTION ASSESSMENT: COMPARISON BETWEEN GATED SPECT VENTRICULOGRAPHY AND ECHOCARDIOGRAPHY

DOBUTAMINE RADIONUCLIDE VENTR1CULOGRAPHY: Prediction of Ventricular Function Improvement After Bypass SurgeD' in Patients with Ischemic Cardiomyopathy N.Zafrir, B.Vidne, R.Basse~4tch, SSclarovsky, E.Lubin, Rabin Medical Center, Beilinson Campus, Israel Ventricular function may improve after coronary B'pass surgeD' (CABG) in patients (pts) ~4th ischemic cardiomyopathy (IC) depending on the amount of contractile myocardial reserve. The use of low-dose dobutamine (DOB) radionuclide ventriculography (RNY) in the assessment of functional contractile reserve has not been criticaUy evaluated. We prospectively studied 35 pts with IC (mean EF 23+5%) and triple vessel disease one month prior to CABG. All underwent a 2-day protocol: day 1 - Tc 99m sestamibi (SM) (25mci) SPECT imaging at rest, performed for viabili~" scoring (15 segments); day 2 - RNV prior to and during infusion of 5 and 10 gg/kg/min of DOB. An increase of global EF from rest to DOB was calculated and value of 10% was considered as cutoff for predictive value. Two pts died within one month of CABG. The rest (33 pts) were followed for 12+5 months. Of these, 16 showed improvement (AEF >5% mean 10+5%) and 17 did not (AEF <5% mean -1+3%). An increase of DOB EF was demonstrated as the most uni~ariate predictor for EF improvement after CABG. The sensitivity, Specificity, positive and negative predictive values of DOB RNV were 65%, 92%, 92% and 67%, r e ~ v e l y . Conclusions: DOB RNV is a useful method to assess and predict functional improvement after CABG in pts with IC. However, a low negative predictive value may be a result of severe ischemia provoked by a low-dose DOB.

CIOGLIA G, SCHINTU B, CHERCHI A ; Institute of Cardiology, University of Cagliari, Italy The study compared gated spect ventriculography (GSV) and echocardingraphy (ECHO) in the evalutation of left ventricular wall motion. GSV and ECHO was performed at rest, in the same day, in 15 subjects with ventricular dysfunction and alterations of contractility secondary to ischemic and idiopathic cardiomyopathy, clinically stable. The patients underwent contrast ventriculograph), (CV) and angiography within 1 week. No significant differences were found between mean score of regional contractility given to each segment by GSV and ECHO. Abnormal regional wall motion was observed by both the tecniques in 2 of 3 patients with single vessel disease and in 2 of 3 with double vessel disease, GSV has pointed out alterations in 4 of 5 and ECHO in 5 of 5 subjects with triple vessel disease. Abnormal regional contractility was detected in 8 of 11 patients with significant coronary stenosis by GSV and in 9 of 11 by ECHO. Abnormal global contractility was observed by both the tecniques too, in 2 of 4 patients without coronary disease, but with dilatative cardiomiopathy and decreased ejection fraction (EF). A significant linear correlation was found between EF measured by GSV ( mean value 40 +/- 22% ) and ECHO ( 44+/- 17% ), R 0,89 , P<0,001. Moreover a significant correlation was calculated between EF measured by GSV and CV ( 48+/-21% ), R 0,87 P<0,001. GSV correlates with echoeardiographic assesment of regional and global function and with angiographyc findings.

W E D N E S D A Y P M A P R I L

Journal of Nuclear Cardiology January/February 1997, Part 2

100.42

100.44

COMPARISON OF THE VALUE BETWEEN RADIONUCLIDE ANGIOGRAPHY AND ELECTRON-BEEM CT IN A S S E S S I N G LEFT V E N T R I C U L A R F U N C T I O N ST.Li, XJ.Liu, RP.Dai, RF.Shi, SX.Zhang, ZM.Yao, Yz.Liu.Fu Wai Hospital, CAMS & PUMC, Beijing, China.

RELATION OF EJECTION F R A C T I O N C H A N G E WITH E X E R C I S E TO EJECTION F R A C T I O N AT REST IN C O R O N A R Y ARTERY DISEASE P.G. Supino, E.M. Herrold, J.P. Teevan, J.S. Borer. Cornell Medical Center. New York, NY, USA

To compare the radionuelide angiography(RNA) and EBCT in assessing LV function, 23 pts (60-+ 8yrs,22M,1F) with CAD were studied. R N A was performed using Siemens multiSPECT system with LEAP collimator by Tc-99m labeling o f RBC(in vivo)at ANT, 30°LAO and 70°LAO views. L V function was measured by Imatron C-150 EBCT system at the views o f ANT, 30°LAO.Student's paired t-test and C o h e n ' s Kappa test were used to identify the difference and agreement between RNA and EBCT. The results were showed following: RNA EBCT ,/ EF 55.4 +- 19.4% 46.9+- 11.8% 0:85 abn.WM 41 segments 38 segments K=0.584, P<0.05 In conclusion: There was a significant correlation between R N A and E B C T in assessment o f LV function and regional wall motion.

Change (A) in LV ejection fraction(EF) from rest(r) to exercise(ex) is a primary prognostic index in pts with coronary artery disease(CAD) but discrepancies have been reported in its independent value, possibly resulting from a systemic relation between the magnitude and variation in ALVEF and absolute LVEFr. To test this hypothesis, we analyzed data from 2764 clinically stable, non-operated pts who underwent r and ex radionuclide cineangiography for CAD, substratified tbr LVEFr: < 3 0 % ( n = 2 1 4 ) , 3040 %(n = 5 9 5 ) , 60-75 %(n = 3 3 6 ) and > 75 %(n = 3 4 ) . For all pts, LVEFr=48.3___ 11.7% and LVEFex=48.7_+ 15.6%. Standard deviation of A L V E F (ASD) in pts with L V E F r < 3 0 % was 4.1%, substantially less than in other subgroups (ASD 7.8% to 9.9% [ p < . 0 0 0 1 , L V E F r < 3 0 % vs. other subgroups]). Also, absolute magnitude of av ALVEF was substantially smaller (p < . 0 0 0 1 ) in pts with L V E F r < 3 0 % than others. Thus, LVEFex is strongly dependent on LVEFr and is more closely tied to L V E F r in the markedly subnormal range.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

100.45 ASSESMENT OF MYOCARDIAL VIABILITY WITH LOW DOSE DOBUTAMINE RADIONUCLIDE VENTRICULOGRAPHY. COMPARISON WITH REST THALLIUbl- 201/STRESS MIBI DUAL ISOTOPE MYOCARDIAL PERFUSION SPECT.

E. Alexanderson, M.L6pez, A. Puente, D. Victoria, D. Bialostozky. Instituto National de Cardiologia "iguaeio Chfivez" M~xice City,

M~X]CO.

Abstracts Wednesday afternoon, April 9, 1997

100.47 ANGIOSCINTIGRAPI-IY IN ARHYTHMOGENIC RIGHT VENTRICULAK CARDIOMYOPATHY

(ARVC) : C O M P A R I S O N

OF FACTOR

ANALYSIS

TO F O U R I E R A N A L Y S I S . D. Daou, R. Lebtahi, Y. Petegnief, M. Faraggi, D. Le Guludec, Nuclear Medicine Deparmaent, Biehat Hospital, Paris, France.

Rest Thallinm-201/stress Tc-99m Sestarnibi dual isotope protocol with late thallium redistribution images is a well accepted teclmique for assesment of myocardial viability. The aim of this study is to asses the utility of low dose dobutamine radionuclide ventriculography(RVG) in identifying viable myocardiem. METHOD: We studied 14 consecutive patients with a previous myocardial infarction. We used a 3mCi rest T1201 SPECT followed by dipyridamole stress and 25 mCi sestamibi inyectien. When it was necessary patients returned next day for 24 hours thallium redistribution images . RVG was performed 3 days after perfusion study using Tc-99m RBC in vivo technique obtaining images in 3 positions (left anterior oblique, anterior and left lateral) at basal state and after 5 and 10 mcg/Kg/mindabutamine infusion. Perfusion data view read using 20 SPECT segments analysis and each segment was scored using 5 points scoring system(0---normal,4=absent uptake). For wall motion analysis, we divided the heart in 10 segmants. RESULTS: We studied a total of 280 perfusion segments, 168 of them with abnormalities(60%). 128 of 168 abnomml segments were considered viables(76%), 40(24%) were fixed. Abnormal wall motion was found in 91/140(65%)segments. 70/91(77%)segmentsimproved wall motion after tow dose dobutamine. 82/128(64%) of viable segments improved after dobutamineinfusion; while only 4/40(10%) of fixed defects improved. In patients with 10 or more abnormal perfusien seo~,nentswith improvement of wall mofiou after dobutmnine global ejection fraction (EF) increased ftom 4 to 18% while in those without improvementof wall motion, global EF ottly increased from l to 4%. CONCLUSIONS:low dose dobutamine RVG is aal useful alternative non invasive procedure for assessing myocardial viability.

The value o f Fourier analysis in the diagnosis o f A R V C has been reported previously. The value o f factor analysis in the detection o f wall motion abnormality ( W M A ) has been reported. W e compared in 14 patients with A R V C , factor analysis to Fourier analysis. E a c h patient had an E C G - g a t e d acquisition in the right a n d left anterior oblique (RAO, L A O ) and left lateral (LL) views : 16 frames/cycle, 600 kcounts/frame, matrix 64x64. The right ventricle (RV) was divided into 4 segments : apical, outflow tract, free and inferior wall. In terms o f patients, factor analysis was discordant with Fourier analysis in respectively 7/14, 1/14 and 3/14 pts on the LL, L A O and R A O views (NS). In terra o f views, the discordance rate was 11/42 (26 %): 9/42 views w e r e abnormal with Fourier phase analysis and 2/42 views were abnormal with factor analysis , p=0.056. A m o n g segments with abnormalities on Fourier analysis, factor analysis was abnormal in : 8/12 pts, 6/11 pts, 5/9 pts and 10/12 p t s in respectively the inferior wall, the outflow tract, the apex and the free wall. Thus, factor analysis provides different information from Fourier phase analysis: it seems to present more W M A in the apex but less in the outflow tract and inferior wall.

100.46

100.48

Age and left ventricular ejection fraction identify Patients with advanced breast cancer at high risk of development of epirubicin induced heart failure

STUDY OF SYSTOLIC AND DIASTOLIC LEFT VENTRICULAR FUNCTION IN RESPONSE TO DIFFERENT DOSES OF DOBUTAMINE A. Maceira, A. Cabrera, MJ. Garcia-Velloso, V. Albaladejo, A. Villas, J. Richter, I. Coma-Canella. University Hospital of Navarra. Pamplona. Spain.

B. Schaadt, H. Kelboek.Department of Clinical Physiology and Nuclear Medicine, Rigshospitalet, Denmark. To evaluate the possibility of predicting developmentof heart failure we monitored left ventrieular ejection fraction (LVEF) in addition to demographicdata in patients with advanced breast cancer treated with epirubiein. Consecutivepatients with metastatic or mtresectable progressive breast cancer were included in the study. LVEF determined by mulfigated radionuclide cardiograph),was performed serially before, during and after treatment with 130 mg epirubiein/m2 body weight every 3 weeks until a cumulative dose of 1,000 mg/m2, without knowledgeof the LVEF values during treatment. Of 89 patients 8 developed heart failure, 7 of these 3-8 months after the last dose of epirubicin. The age was 5-8 years higher and baseline LVEF 7% lower (95% coufidens intervals (CI) 3% to 13%) in patients with heart failure than in the remaining patients. LVEF was slighly reduced in all patients irrespective of later heart failure. Receiver operating characteristic curves demonstrated an intermediate diagnostic value of the milfimal LVEF and a low diagnostic value of the LVEF decrease of the serial determinations of LVEF during treatment from 0% to 90% of the maximal cumulative epirubiein dose, as predictors of heart failure. Three combinedcriteria, age > 50 years, baseline LVEF < 60%, and a decrease in LVEF to < 50% had a predictive value of a positive test 0f75% (95% CI 35% to 97%) end a predictive value of a negative test of 98% (90% to 100%) with regard to developementof heart failure. ConventionalLVEF criteria had no predicdictive value for developementof heart failure. Our results indicate that age and baseline LVEF determination identify a group of patients with advanced breast cancer at high risk of developing epirubiein induced heart failure, in wbom monitoring of serial LVEF during treatment is indicated, but is of no value in the other patients. Discontinuationof chemotherapyshould be considered in patients with a decline in LVEF to a value < 50%.

Ten healthy volunteers (aged 22 _+ 2.), were submitted to a dobutamine (DB) infusion x~4th increasing doses. Three equilibrium ventriculographies were taken, baseline (BA), at 101ag/K/min (DBI0) and at 40lxg/K/min (DB40). Ejection fraction (EF), EF in the first third o f systole (EF3) mad peak filli~ ?FR) were studied. EF EF3 PFR BA 64_-24 22_46 5+_2 DB 10 77+_3 3746 6-2-_1 DB 40 8 L+4 35~ 7+_2 Significant differences ~ r e found for all the variables among the three measurements (p<0.001, p<0.001, p=0.027). Baseline EF and EF3 were significantly lower than DB10 (p<0,001,p<0.0l) and DB40 values (p<0.001). Baseline PFR was only significantly different from DB40 PFR (p=0,033). Between the two doses of dobutamine, only EF was significantly higher at the maximal dose. We conclude than low dose dobutamine leads to enhanced EF, EF3 and PFR, whereas a higher dose only modifies global EF, with no difference either in the first third o f systole or in diastole.

S121

S 122

Abstracts Wednesday afternoon, April 9, 1997

Journal of Nuclear Cardiology January/February 1997, Part 2

100.49

100.51

~

CARDIAC ABNORMALITIES IN ASYMPTOMATIC HUMAN IMMUNODEFICIENCY VIRUS CARRIERS: AN ECHOCARDIOGRAPHIC AND RADIONUCLIDE ANGIOGRAPHIC FOLLOW-UP. C. Morillon, J. Sztajzel, M. JeanprStre, R. Lerch, O. Hubmann, A. Righetti. Cardiology Center, University Hospital, Geneva, Switzerland. We have previously shown that cardiac abnormalities, especialy right ventricular involvement, are frequent in asymptomatic patients (pts) human immunodeficiency virus (HIV) infected. 53 asymptomatic pts were initially studied by both RNA and echocardiography. At rest, 62 % of these pts had cardiac abnormalities including right ventricular impairment (43%), left ventricular abnormalities (4%), and dysfunction of both cavities (15%). Are these cardiac abnormalities transient or persistent? In order to answer this question, we investigate 36 pts. During the follow-up (FU) of 31+10 months, 9 died, 9 refused iterative investigations and 18 (15 males, mean age 38+6, 3 pts with AIDS) were reinvestigated. Of these 18 pts, 15 had fight ventricular impairment (dilatation and/or dysfunction), at the first RNA, persisting in 13 pts during FU. Moreover, diastolic left ventficular function is pathologic in 8 of these 13pts. Left ventricular ejection fraction decreases (63+4.7 vs 60+6.5, NS) during FU. No pt had pulmonary hypertension on echocardiography. In conclusion, these preliminary data show that the frequent right ventricular abnormalities, detected by RNA in earlier stage of disease are in the great majority persistent, in the absence of pulmonary involvement.

ROGNOSTIC SIGNIFICANCE OF RESTING LEFT NTRICULAR EJECTION FRACTION IN BONE MARROW TRANSPLANT PATIENTS. A.F. Jacobson. VA Medical Center, Seattle, WA, USA. Although patients (pts) undergoing bone marrow transplantation (BMT) often have previously received chemotherapy with potential myocardial toxicity, the prognostic utility of pre- and post-BMT determination of resting left ventricular ejection traction (EF) has received limited attention. During a ten-year period, Tc-99m-labeled red blood cell radionuclide ventriculography (RNVG) (normal (nl) EF _>50%) was performed on 310 pts (mean age 36, range 19-63) prior to BMT. 207 pts who survived to 3 months post-BMT also had a second RNVG 21-139 (mean-75) days post-BMT. One-year survival (1YS) was examined relative to pre- (EF1) and post-BMT EF (EF2). EF1 range was 36% to 86%, being normal in 254 pts (82%). 1YS was 55% both in pts with nl and low EF1. Among all EF1 groups, only pts with EF1 >70% had significantly poorer 1YS ((3/12; 25% vs 168/298; 56%) p<0.025). Results were similar for EF2 (range 30%-78%); 1YS was 70% in pts with nl EF2, 67% in pts with EF2<50% (p=ns). 1YS was lower in EF2_>70% pts (6/11;55%) compared with the others (137/196;70%), but the difference did not reach significance (p=0.15). In BMT pts, high EF (270%) is associated with a poorer prognosis, while 1YS is similar for those with lower nl (5069%) and moderately reduced EF (30-49%).

W E D N E S D A

Y P M A P R I

L 9

100.50

100.52

EJECTION FRACTION CHANGES WITH DIFFERENT FORMS OF STRESS. STUDY IN HEALTHY VOLUNTEERS I. Coma-Canella, MJ. Garcia-Velloso, A. Maeeira, A. Cabrera, V. Albadalejo, A. Villas, JA. Richter. Chnica Universttaria de Navarra, Pamplona, Spain.

MONITORING OF THE LEFT VENTRICULAR FUNCTION WITH A MULTIDETECTOR NUCLEAR PROBE. IN VIVO TEST/NG A. Millaire, J. Rousseau, C. Foucher-Hossein,H. Bedoni, P. de Groote, X. Marehandise, G. Ducloux.Universityof Lille, France.

Pharmacologic stress tests are widely used instead of physical exercise. It is assumed that an increase in eiection fraction (EF) <5 units is abnormal, but no study has compared the EF response among different forms of stress. For this reason 40 healthy volunteers (aged 22_+1.5) were submitted to equilibrium radionuclide angiography in baseline conditions (b) and during different stress tests (s). Four groups with 10 persons each were established : 1supine bicycle ergometry (EX); 2- dobutamine (DB); 3adenosine triphosphate (ATP) and 4-dipyridamole (i)P). NS difference amon~ grouos was found in age, baseline EF, heart rate and-systolic blood pressure. The EF increased significantly with each form of stress. Comparative values among groups are shown in the table :

We have developped an original ambulatory nuclear probe for monitoringthe left ventricular ejectionfraction (EF). The probe is made of 5 iodide cesium detectors (D). The central D (area 2.25 cm2) is designedfor assessing the global EF and the 4 peripheral D (area 1 cm2) are designed for detecting artifactual probe displacements and assessing regional EFs. Twenty five patients were investigated(20 males, 5 females, age 55 ,t: 15 years). Data acquisition was performed at rest after labeling red blood ceils with 20 mCi 99~1"cand after positioning the probe under gamma camera. The data of each D were compared to those obtained x~qth the ganama camera (global EF and regional EF by sectorial analysis). An artifactual probe displacementwas then performed with a further return to the correct position. Correlations concerning global EF (r = 0.71) and regional EFs (anterior region : r = 0.60 ; lateral region : r = 0.51 ; inferior region : r = 0.52 ; septal region : r = 0.52) were significant (p<0.01). The artifactual probe displacement could be blindly detected by 2 independent observers and was diagnosed by the occurrence of a backgroundlike signal in at least 1 peripheral D. In conclusion, our study suggests that our probe provides an accurate tool to assess the left ventricularcontractilityin patients. The multidetectordesign is an advantageby allowingdetectionof artifactual probe displacements and could allow the detectionof regional contractilitydisorders.

b EF s EF A EF

EX 6~+4 76+_.3 13+5

DB 65+4 81+4' 16_+6'

ATP 62+_5 7i+4 9+_.3

DP 63+_4 67+4 4+-3

~qS <0.05 <0.05

The EF reached higher values with DB vs : EX, ATP and DP. It also reached higher values with EX vs DP. The increment in EF (AEF) was si~ificantly hi daer with EX vs DP. It was also higher witli DB vs D P a n d ATP. In conclusion, the EF increases with every form of stress, but the highest values occur with DB and the lowest with DP.

Journal of Nuclear Cardiology Volume 4, Number 1, Part 2

Abstracts Wednesday afternoon, April 9, | 997

100.53

100.55

ICRF-187 PREVENT C A R D I O T O X I C I T Y : A R A D I O N U C L I D E V E N T R I C U L O G R A P H Y STUDY.

RADIONUCLIDE VENTRICULOGRAPHY EVALUATION OF RIGHT AND LEFT VENTRICULAR PERFORMANCE IN PATIENTS REFERED FOR LUNG TRANSPLANTATION.

M.L.DeRimini,M.Orditura,D.Capobianco, L.Mansi-II Italy.

University

of

Naples-

ICRF-187 (I) has been p r o p o s e d to prevent Doxorubicin (D) induced c a r d i o t o x i c i t y . w e p e r f o r m e d RNV Rest/ Stress(R/S) in 16 o n c o l o g i c a l pts u n d e r g o i n g p o l i c h e m o t h e r a p y including D without CAD and with normal LV function. Studies were performed a f t e r 3 ( T l ) a n d 8(T2) cycles. I0 pts received only D(Grl), 6 pts (Gr2)underwent a 1000 mg/sqm standard dose of I before CT.In G r l at T2 R EF was normal, PFR(EDV/s) and P F R / P E R were d e c r e a s e d in 3 pts and TPFR was prolonged in 5pts. At T2 S 3 pts with septal h y p o k i n e s i a were observed. No a b n o r m a l i t i e s both at T1 and T2 were observed in Gr2. We confirm the role of I in c a r d i o p r o t e c t i o n in pts with CT and d i a s t o l i c function indexes as early m a r k e r of LV dysfunction.

S123

N Valli. C. Dromer, JL. Barat, L. Labbr, L. Bordenave, D. Ducassou, Bordeaux University hospital, departments of nuclear medicine and eardio thoracic surgery. If right ventricular (RV) dysfunction is common in patients with chronic lung disease, left ventricular (LV) dysfunction is still controversial. Nevertheless this alteration has to be considered in patients referred for lung transplantation (LT) to envisage a possible left catheterization and associated heart transplantation (HT). In 27 patients with lung parenchymal disease who were refered for ruT, we used radionuclide ventriculography (first pass and equilibrium) from which RV and LV ejection fraction (EF) and LV diastolic parameters were measured. The mean RVEF was significantly lower than the normal value and there was a significant inverse linear correlation between RVEF and right ventricular afterload. Mean LVEF was normal but we find a reduced LV diastolic function (LVDF). These data suggest that radionuclide ventriculography is a safe and reproducible mean to estimate PAP in patients refferred for LT and may contribute to the indication of associated HT in patients with elevated PCP and LV diastolic dysfunction.

100.54

100.56

DIABETES MELLITUS DETERIORATE LEFT VENTRICULAR FUNCTIONS UNDER LOW-DOSE DOBUTAMINE STRESS IN CAD PATIENTS: AN ASSESSMENT WITH RADIONUCLIDE ANGIOGRAPHY. SP Yang, CY Cheng, WL Chen, DA Wu, DJ Wang. TriSePcice General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC.

CONTINUOUS MONITORING OF LEFT VENTRICULAR FUNCTION (LVF) USING MOBILE GAMMA CAMERA (MGC) IN PATIENTS(PTS)UNDERGOING NONCARDIAC SURGERY J. Tian, M.Imbriaco, S.DJ. Yeh, A.H.Freiman, SM. Larson. Memorial Sloan-Kettering Cancer Center, New York, USA

Diabetes-induced abnormalities in the myocardium are well accepted. This study is to evaluate the superimposed effect of diabetes mellitus (DM) on LV performance under pharmacologic stress in CAD patients. Fifteen normal subjects (N) and 30 CAD patients (18 without DM, C-DM; 12 with DM, C+DM) were included and underwent low-dose dobutamine stress (O, 5, 10, 15, and 20 i~g/kg/m!n) radionuclide angiography (RNA). The parameters of LV systolic function (ejection fraction, EF; peak ejection rate, PEF) and diastolic function (peak filling rate, PFR) at 0 (basal) and 20 p.glkg/min of dobutamine infusion were: N basal

20

C-DM basal 20

CAD+DM basal 20

EF 56+7 69+8a 56+5 55+_9 50+_7 52+_11 PER 3.1_+0.3 5.2+0.6b 2.6+_0.4 3.6+0.6a 2,5+-0.7 !3.0+0.9 PFR 2.7+0.5 4.0+0.7b 2.5+0.5 2.7_+0.8 2.3_+0.4 2.4+_0.8 a
General anesthesia and major surgical interventions are known to cause significant cardiac stress that may induce acute myocardial ischemia in pts with coronary artery disease (CAD). This study was to assess the value of MGC for the monitoring of LVF as a marker of myocardial ischemia in pts undergoing noncardiac surgery. Thirty-three pts ( 27 M, 6 F, mean age 70 + 9 yr ) underwent the monitoring of LVF for mean 4.2 -+ 1.4 hr (range 2 to 7 hr) and Holter electrocardiogram (ECG) for 24 hr within mean 14.8 + 4.9 (range 1 to 21)hr after noncardiac surgical procedures. MGC and Holter ECG were nermal in 9 pts with no history of CAD. In 24 pts with CAD, 17 pts had resting LV ejection fraction (EF) >- 50%. Fifteen of them showed no obvious changes during the monitoring of LVEF and ST segments. Two pts developed three asymptomatic episodes of transient decrease (12-14%) in LVEF associated with apical or global hypokinesis. One of these 3 episodes suggestive of ischemia was accompanied by ST segment depression on ECG. The remaining 7 pts had resting LVEF between 25-45% but no significant changes in serial LVEF and ST segments during the monitoring period. Our preliminary data shows that MGC identifies transient ischemic events in a small population of patients with CAD in the early hrs after surgery. Further studies are needed to determine whether the MGC is an useful imaging tool for the detection of perioperative myocardial dysfunction following major noncardiac surgery.

S124

Abstracts Wednesday afternoon, April 9, 1997

100.57

100.59

LEFT VENTRtCULAR FUNCTION UNDER LOW-DOSE DOBUTAMINE STRESS IN DIABETIC PATIENTS WITH MYOCARDIAL PERFUSION DEFECTS: AN ASSESSMENT WITH RADIONUCLIDE ANGIOGRAPHY. CY Cheng, SP Yang, DA Wu, WL Chen, DJ Wang. TriService General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC.

DETECTION OF LEFT AND RIGHT VENTRICULAR KINETICS ABNORMALITIES B Y GATED BLOOD POOL SPECT, IN MITRAL VALVE PROLAPSE. D. Casset-Senon, V. Eder, C. Delhomme, L. Fauchier, L. Philippe, JP. Fauchier, JM. Pottier, P. Cosnay. Trousseau Hospital, Tours, France. Patients with mitral valve prolapse (MVP) frequently have ventricular rhythm disorders. In 36 patients (19 M, 47 ± 15 years), gated blood pool SPECT with Fourier phase analysis was performed and results were analyzed in relation with ventricutar arrhythmia observed on 24H ambulatory continuous ECG recording. Isolated premature beats (I and II Lown gradings)were found in 21 pts and severe arrhythmias (> III Lown grading) in 15 ones. The results showed right ventricular (RV) ejection fraction alteration, RV kinetics disorders, but also ventricular asynchronisms in phase images and delayed phase abnormalities in RV but even in left ventricle (LV). These disorders were more marked in pts with mitral regurgitation but especially in pts with severe arrhythmias.. So that, gated blood pool SPECT with Fourier analysis allow to assess both kinetics disorders and activation - contraction spreading abnormalities, in mitral valve prolapse. These abnormalities, more marked in RV, seem to suggest the presence of organic or functional lesions areas which importance was close related with the ventricular arrhythmia severity.

Diabetic cardiomyopathy is one of the noncoronary diseases that can induce thallium-201 myocardial perfusion defects. To study the left ventricular (LV) systolic function (ejection fraction, EF; peak ejection rate, PEF) and diastolic function (peak filling rate, PFR) in patients with diabetic mellitus (DM), rest radionuclide angiography (RNA) and low-dose dobutamine stress (5, 10, 15, and 20 i~g/kgtmin) RNA were performed for 9 normal subjects (N) and 16 diabetic patients with angiographicaily normal coronary arteries. Of the 16 diabetics, 9 revealed normal stress thallium-201 myocardial perfusion (DMn) and 7 had perfusion defects (DMpd), In N, DMn and DMpd, dobutamine stress could increase the LVEF and LVPER significantly. PFR in N revealed significantly increased, from 3.0_+0.6 to 4.3+_0.6 end-diastolic volumes (EDV)/sec. In contrast to N, DMn demonstrated similar PFR (2.8_+0.4 to 3.0_+0.6 EDV/sec, NS) and DMpd revealed a decreasing trend of PFR (2.7_+0.4 to 2.5_+0.6 EDV/sec, NS) during dobutamine infusion. It is therefore concluded that DM may deteriorate the LV diastolic function and aggravate it when DM is accompanied by myocardium abnormalities.

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RADIONUCLIDE METHODS IN PROGNOSIS OF EARLY PERIOD AFTER CARDIOMYOPLASTY Lishmanov Yu, Chernov V., Akhmedov Sh., Kiselev V., Vesnina J. Departments of Nuclear Medicine and Cardiac Surgery, Tomsk Institute of Cardiology, Russia

W E D N E S D A Y P M A P R I L 9

Journal of Nuclear Cardiology January/February 1997, Part 2

The aim of study was to estimate the prognostic value of gated equilibrium radionuclide ventriculography and dipyridamole thallium-199 myocardial scintigraphy in early period after cardiomyoplasty (CMP). 24 pts with hard cardiac failure were studied 2-3 weeks before CMP. Ejection fraction (EF), persistent (PDV) and reversible (RDV) myocardial perfusion defect volumes were estimated. On results of supervision of pts in early period a~er CMP all of them were divided into 3 Groups: Gr. 1 - 9 pts with heavy condition, Gr.2 - 8 pts with midheaw condition and Gr.3 - 7 pts with satisfactory condition. The results are as follows: Gr. 1 Gr.2 Gr.3 EF, % 18.6+2.2 27.6_+2.3* 34.3+2.3** RDV, % 4.0+4.1 7.6+1.8 12.3_+3.2" PDV, % 41.1_+4.4 33.0+4.6 24.5+4.8** *-p<0.05; **-p<0.01 vs Gr. 1 Thus, severe PDV, low EF and small RDV are predictors of risk of heavy condition in pts after CMP.