Prognostic significance of dipyridamole Tc-99m sestamibi SPECT imaging for the evaluation of ischemic heart disease

While the prognostic value of dipyridamole (DIP) planar thallium-201 imaging is well established, no prognostic studies of DIP Tc-99m sestamibi (MIBI) SPECT imaging have been reported. Accordingly, the imaging results of 138 sequential, un-selected patients (pts) referred for DIP MIBI SPECT studies were characterized as demonstrating ischemia (IS) of no IS. The presence or absence of IS was compared with subsequent cardiac events during an average follow-up period of 8.5 months. Events included cardiac death in 2 pts, MI in 1, admission for unstable angina pectoris in 2 and need for revascularization in 20. Cardiac events occurred in 24/64 pts (38%) with IS and only 2/74 (3%) with no IS (p<0.001). There was no cardiac death or MI in the no IS group. The 26 pts with events and 112 pts. without events were compared with regard to age, sex, history or diabetes mellitus, hypertension, prior MI, prior revascularization and the presence of IS on DIP MIBI. Only age (71 vs 66 years, p<0.001) and the presence of IS (92% vs 36%, p<0.001) were significantly different between the groups. The presence of ischemia with dipyridamole Tc-99m sestamibi SPECT imaging has prognostic value in predicting future cardiac events in patients referred for pharmacologic stress testing. (author). 1 fig