Comparison of gated sestamibi myocardial perfusion imaging between upright solid state and standard supine gamma systems

S14 Abstracts Friday, October 1, 2004 Journal of Nuclear Cardiology July/August 2004 St. Francis Hospital, Stony Brook University, State University of New York, Roslyn, NY; Long Island Jewish Medical Center, New Hyde Park, NY Background: Ischemic left ventricular (LV) dysfunction may occur after exercise, but is regarded as uncommon after vasodilator stress. We evaluated the prevalence of LV dysfunction post-adenosine (ado) in relation to the extent of reversible perfusion defects (PD) and angiographic coronary artery disease (CAD). Methods: 86 patients (pts.) referred for adenosine dual-isotope gated SPECT were studied: 43 with ⱖ 1 reversible PD, and 43 age and sex matched controls without CAD who had normal LV perfusion and function. Extent of reversible PD was defined by 20-segment/5-point summed difference score (SDS), and SDSⱖ 8 defined severe PD. LV ejection fraction (EF) and segmental wall thickening (WT) were quantified at rest and 60 minutes post-adenosine by QGS (Cedars-Sinai Medical Center, Los Angeles, CA). Coronary angiography was performed in 36/43 pts. with PD. Results: See Table. LAD stenosis ⱖ 50% (% pts) Extent PD EF ado Drop in WT ado vs. rest Stenosis Vessels with stenosis ⱖ 50% SDS  8 (n  18) SDS ⱖ 8 (n  25) p 55
12% 3
13% 38
33% 1.1
1.1 38% 44
15% 13
16% 69
28% 2.5
1.1 82% 0.02 0.04 0.01 0.01 0.02 LAD  left anterior descending. SD  standard deviation. Conclusion: Global and segmental LV dysfunction indicative of stunning was observed in pts. with severe reversible PD post-adenosine, and identified pts. with more extensive CAD. 31.45 EFFECT OF PRONE POSITION AND ATTENUATION CORRECTION ON TEST CHARACTERISTICS OF MYOCARDIAL PERFUSION IMAGING IN FEMALE PATIENTS WITH BREAST SHADOW ARTIFACTS RS Druz, KJ Nichols, K Ngai, R Dim, OA Akinboboye, N Reichek St. Francis Hospital, State University of New York at Stony Brook, Roslyn, NY; Long Island Jewish Medical Center, New Hyde Park, NY Background: Anterior wall defects due to breast decrease specificity of myocardial perfusion imaging (MPI) in female patients (pts.). We compared prone position uncorrected (PRN), supine uncorrected (NO AC), and attenuation corrected (AC) MPI for perfusion scores, sensitivity, specificity, and diagnostic accuracy in women. Methods: 68 female pts. (70
12 yrs) with () or without (-) left anterior descending (LAD) coronary artery stenosis ⱖ 70% underwent rest TL-201/ stress Tc-99m sestamibi MPI as follows: NO AC  simultaneous AC. 45/68 pts. also had PRN. All pts. had: breast shadow on the raw data; anterior, anteroseptal, or apical defects in the LAD distribution as per AHA/ASNC position statement; no anterior wall infarct; diagnostic angiography within 30 days of MPI. Summed stress perfusion scores were based on a 5-point/17-segment model, and % myocardium in the LAD territory perfusion defects (% LV) was calculated from the scores. Friedman rank test was used for %LV, and McNemar’s test for statistical significance (p0.05) between tests’ results. Results: See Table. %LV % LV %LV ALL LAD() LAD() Sensitivity PRN (n  45) NO AC (n  68) AC (n  68) p 4% 3% 6% (n33) (n12) 6% 4% 9% (n46) (n22) 8% 5% 12% (n46) (n22) 0.0001 0.005 0.007 Sensitivity Accuracy 50% 94% 82% 86% 61% 68% 83% ns 79% 80% 0.001 PRN 0.02 PRN and AC vs. and AC vs. NO AC NO AC Conclusion: %LV was lowest with PRN, and highest with AC MPI. Compared with NO AC, AC and PRN MPI had increased specificity and accuracy but a trend to a lower sensitivity was observed for PRN. 31.46 PROGNOSTIC UTILITY OF TC-TETROFOSMIN DIPYRIDAMOLE STRESS STUDIES IN PATIENTS WITH END-STAGE RENAL DISEASE (ESRD) ON CHRONIC DIALYSIS K-T Ho 1, S Pary 2 Cardiac Department, National University Hospital, Singapore Department of Renal Medicine, National University Hospital, Singapore Background: Patients with end-stage renal disease (ESRD) have a higher prevalence of and mortality from coronary artery disease (CAD) than the general population. The prognostic utility of SPECT Technetium-tetrofosmin dipyridamole stress myocardial perfusion imaging (MPI) in this population is unknown. Previous studies have also cast doubts on the efficacy of dipyridamole-stress in this scenario. Methods: A consecutive series of 226 patients with ESRD on chronic dialysis underwent dipyridamole stress Tc-99m tetrofosmin SPECT imaging over 3.6 years (Jan 2000 Aug 2003) at the National University Hospital, Singapore. This represents 9% of all patients in Singapore (population 4 million) on chronic dialysis. Uniform methods of data collection and standardized epidemiologic methods for follow-up were employed. Follow-up was complete in 99% of patients at 2 years. Results: The average age was 58 years (range 20 80 years), 120 were male. 138 patients (61%) had diabetes, 193 (85%) hypertension. 176 patients had normal scans. None of these patients with normal scans underwent angiography within 3 months of the index MPI study. At 1.97 years of follow-up, 2 (1%) patients with normal scans had experienced a cardiac event (myocardial infarction / cardiac death), and a total of 21 patients had died (12%). No patients had undergone revascularization. The annualized cardiac event rate was 0.5%. 52 patients had abnormal scans. Of these, 5 patients underwent angiography within 3 months of imaging, 3 then had bypass surgery and 1 angioplasty. 2 patients sustained non-fatal MI. 11 patients died over the follow-up period, of which 2 were due to myocardial infarction. The cardiac event rate (cardiac death/MI/revascularization) in patients with abnormal scans was 15% (annualized rate 8%). Conclusions: 1)The negative predictive value of a normal Tc-tetrofosmin dipyridamole stress test was high and conferred good cardiac prognosis in this population. 2)Dipyridamole-stress is an effective modality in stratifying cardiac risk in patients with ESRD on chronic dialysis. 31.47 COMPARISON OF GATED SESTAMIBI MYOCARDIAL PERFUSION IMAGING BETWEEN UPRIGHT SOLID STATE AND STANDARD SUPINE GAMMA SYSTEMS. SU Ahmed, A Ahlberg, G Cyr, PJ Vitols, A Mann, L Alexander, J Rosenblatt, J Mieres, SJ Cullom, GV Heller Hartford Hospital, Hartford, CT Background: There are no data directly comparing myocardial perfusion imaging (MPI) with upright solid state and standard supine gamma for imaging characteristics and clinical interpretation. Methods: A series of 54 patients underwent clinically indicated upright solid state and standard supine gamma MPI, respectively, in a randomized fashion. Image acquisition time, for both systems, was 25 seconds/projection at rest and 30 seconds/ projection at stress, for 64 projections. Images were interpreted for the presence or absence of coronary artery disease (CAD) and ventricular function by a consensus of 3 expert readers blinded to patient identifiers. Results: There was moderate agreement for the detection of coronary artery disease. Perfusion Supine normal Supine CAD Upright Normal Upright CAD 31 7 5 11 Agreement  78% Kappa  0.486 Total  54 Among patients identified as having CAD by both systems (n11), upright solid state imaging resulted in higher summed stress scores [12.3
8.7 versus 18.1
11.7 (p0.009)] and summed difference scores [4.0
3.2 Journal of Nuclear Cardiology Volume 11, Number 4;S1-S18 Abstracts Friday, October 1, 2004 versus 8.8
6.4 (p0.02)] than standard supine imaging. There was excellent agreement for left ventricular function. Function Supine  50% Supine  50% Upright 50% Upright 50% 38 2 1 8 Agreement  94% Kappa  0.804 Total  49 Conclusion: Upright solid state imaging is equivalent to supine standard gamma MPI for the diagnosis of CAD utilizing myocardial perfusion and function. 31.48 RISK STRATIFICATION OF PATIENTS WITH LEFT BUNDLE BRANCH BLOCK: EXERCISE VERSUS VASODILATOR SU Ahmed, AW Ahlberg, G Cyr, S Navare, D O’Sullivan, GV Heller Hartford Hospital, Hartford, CT Background: ACC/ASNC guidelines recommend vasodilator stress for the diagnosis and risk stratification of patients with left bundle branch block (LBBB) regardless of exercise capacity. There are no data comparing exercise and vasodilator gated stress myocardial perfusion imaging (MPI) for risk stratification of patients with LBBB. Methods: A consecutive series of 418 patients with LBBB underwent exercise (n230) or vasodilator (n188) stress MPI based upon physician perception of exercise capacity. Images were interpreted by a blinded consensus of 2 readers, using a standard 17 segment model. Abnormal perfusion and function were defined as summed stress score (SSS) 3 and ejection fraction (EF) 50%, respectively. Functional capacity, measured in metabolic equivalents (METS), was determined for patients completing Bruce protocol (n223). Follow-up for myocardial infarction (MI) or cardiac death (CD), obtained by letters, telephone contact, review of medical records and social security death index, was 94% complete (mean30.2 months
15.2 months). Results: The rate of MI or CD was 8.6% (20/230) and 13.8% (26/188) with EX and VASO, respectively (p0.089). Patients with abnormal perfusion or function had a significantly higher event rate than those with normal perfusion or function with either EX or VASO. Ex Vaso SSS  3 SSS  3 P value EF  50% EF  50% P value 6.2% 12.3% 17.9% 18.0% 0.006 0.027 1.6% 7.2% 17.0% 19.0% 0.001 0.02 Patients achieving 7 METS had an event rate of 2.3% (2/87) versus 12.5% (17/136) for ⱕ7 METS (p0.016). For risk stratification, a model was constructed to classify patients as low- or high-risk for CD or MI using the following criteria: Low Risk EX with either: SSSⱕ3 or EF ⱖ50% or  7 METS High RiskAll VASO and EX with either SSS3 or EF50% or 7METS Event rates were 4.0%% (7/175) versus 18.2% (55/302) in patients classified as low- or high-risk, respectively (p0.001). Conclusion: In patients with LBBB, exercise MPI should be the first consideration as this stressor modality allows a highly effective risk stratification for subsequent cardiac events using a combination of myocardial perfusion and function data, in addition to functional capacity. 31.49 SIGNIFICANTLY HIGHER PREVALENCE OF CAD IN ASYMPTOMATIC MALE SMOKERS AS COMPARED WITH THEIR FEMALE COUNTERPARTS S Chiadika, M Lue, DK Blood, SR Bergmann, S Bokhari College of Physicians & Surgeons Columbia University, NY, New York. Objective: The incidence of coronary artery disease (CAD) as detected by myocardial perfusion imaging (MPI) in asymptomatic smokers is unknown. The objective was to compare the prevalence of CAD among male and female smokers who underwent dobutamine (DBA) stress test with MPI. Methods: We performed a retrospective cohort study on 192 smokers (99 males, mean age 70  11 years and 93 females, mean age 72  10 years) with severe COPD and no history of CAD, referred for DBA stress MPI for non-vascular elective surgeries. Clinical risks score for CAD were similar in both groups except more women had diabetes and hyperlipidemia than men. There was no significant difference in the number of pack years of cigarettes S15 smoked. All patients achieved  85% of predicted maximal heart rate with DBA infusion. Results: Overall 64 /192 (33%) had myocardial perfusion defects. The prevalence of defects among males was 53/99 (55%) versus 11/93 (12%) among females, p 0.001. The relative risk of CAD in males was 4.5 times compared to females. The prevalence of multi-vessel disease was higher in men than in women (30% vs 9%), p0.001. Conclusion: In this study, we found a high prevalence of CAD among male asymptomatic COPD patients with extensive smoking history, compared with age and risk factor matched female asymptomatic COPD patients. Pulmonary limitations in males with severe COPD may mask their CAD. 31.50 POST-STRESS TO REST VENTRICULAR VOLUME RATIOS IN DIABETICS COMPARED TO NON-DIABETICS USING GATED SPECT TF Heston Northwest Molecular Imaging, Kellogg, Idaho. Background: Diabetic patients are more likely to suffer a myocardial infarction or cardiac death than non-diabetics. Even among patients with equal myocardial perfusion defect and reversibility scores, diabetics still have a higher risk than non-diabetics. This study was undertaken to see if post-stress to rest left ventricular volume ratios could help explain the higher risk diabetics face. Methods: 188 consecutive outpatients undergoing one day rest-stress Tc-99m sestamibi or tetrofosmin gated SPECT were evaluated using either treadmill (n122) or dipyridamole (n66) stress. Images were obtained using a single head camera. Ventricular volumes were calculated using the Cedars-Sinai QGS program. Post-stress to rest end systolic, end diastolic, average ventricular volume, and left ventricular ejection fraction ratios (ESVr, EDVr, VOLr, LVEFr) were calculated. The summed stress score (SSS), summed rest score (SRS), summed difference score (SDS), and post-stress wall motion score (WMS) was determined semi-quantitatively. Scans were interpreted by a certified nuclear cardiologist. Statistical analysis was performed using the SPSS statistical package. Results: Patients were 51% male, 21% diabetic, 63
13 years of age (mean
std), and had a body mass index of 31
7.4 m/kg2. Diabetic compared to non-diabetic patients were significantly more likely to have a higher ESVr (0.95 vs 0.85, p0.012), EDVr (0.99 vs 0.93, p0.007), and VOLr (0.98 vs 0.91, p0.004). The LVEFr was not significantly different (1.05 vs 1.06, p0.71). Perfusion and wall motion scores were not significantly different in the two groups. Resting and post-stress ESV, EDV, and LVEF values also were not significantly different. After controlling for stress type, diabetics continued to have a significantly higher VOLr (p0.039) and ESVr (p0.023), however, the EDVr (p0.81) became nonsigificant, and the LVEFr (p0.50) continued to show a nonsigificant difference. Conclusion: Diabetics have a significantly higher VOLr and ESVr in spite of equivalent perfusion scores, wall motion scores, and LVEF. These findings may help justify the rationale for gating rest in addition to post-stress images. 31.51 ECG-GATED SPECT MYOCARDIAL PERFUSION IMAGING USING ADENOSINE PHARMACOLOGIC STRESS: DOES CHOICE OF RADIONUCLIDE MATTER? TM Bateman, GV Heller, MD Cerqueira, PG Jones, JR Bryngelson, KL Moutray, LL Gegen, GK Hertenstein, K Moser, JA Case Mid America Heart Institute and CVIT, Kansas City, MO. Introduction: Opinions vary as to whether Tc-99m radionuclides are superior for myocardial perfusion (P) imaging based on their imaging characteristics, or Tl-201 is better because of its uptake kinetics and less problem with inferior wall scatter from splanchnic organs. We designed this study to compare these 2 agents in patients imaged after pharmacologic stress using adenosine (Adenoscan®). Methods: 3 expert reviewers blinded to all clinical data interpreted in random sequence and by consensus the non-gated and gated rest and post-stress SPECT scans of 233 pts (52% male): 116 Tl-201/Tl-201 and 117 Tc-99m-Sestamibi (MIBI)/MIBI. 183 pts had coronary angiography ⱕ 90 days (26%0 CAD; 33%1 VD; 41%MVD) and 50 had low CAD likelihood. Average age was 68 yrs; mean body mass index (BMI) was