962-62 The Use of Exercise-Rest Same Day SPECT Sestamibi Imaging Protocol in Coronary Artery Disease Detection

Abstract

There are several sestamibi imaging protocols, each with certain perceived advantages and limitations. Most published reports are on patients (pts) in clinical trials which may have a hidden bias in pt selection. This study examined our clinical experience using the exercise (10 mCi)/rest (30 mCi) same day SPECT protocol with sestamibi in 132 pts with coronary artery disease (CAD) by angiography and 61 pts with low pre-test probability of CAD. There were 670 pts studied during the same time period but not included because they did not meet the above two criteria. The rest study was combined with first-pass RNA using the Sim-minus;400 gamma camera in 72 pts. There were 112 men and 20 women aged 60 ± 11 years. The pts weight was 179 ± 27 Ibs and height was 68 ± 3 inches. The exercise was adequate (≥ 85% of maximum predicted heart rate or positive S-T response) in 85 pts and submaximal in 47 pts. The overall sensitivity of SPECT was 88% (compared to 27% for S-T depression, P = 0.0001); it was 76% in one-vessel, 84% in two- and 98% in three-vessel disease (P = 0,006). The normalcy rate in 61 pts with low probability of CAD was 95%. The perfusion defects in 116 pts with abnormal images were reversible (complete or partial) in 80 pts and fixed in 36 pts. The left ventricular ejection fraction was 50 ± 12% in pts with reversible and 39 ± 9% in pts with fixed defects (P = 0.0003). In the 72 pts with RNA, there were 15 segments with fixed defects. The wall motion was normal in 2 segments, and abnormal in 13. In 129 segments with no fixed defects, the wall motion was normal in 97 (75%). Thus, the exercise-rest same day sestamibi protocol provides a high diagnostic accuracy for CAD detection and high quality functional studies. The protocol may also eliminate the need for rest studies in pts whose exercise studies are normal.