INDEPENDENT PROGNOSTIC VALUE OF INTRAVENOUS DIPYRIDAMOLE WITH TC-99M SESTAMIBI TOMOGRAPHIC IMAGING IN PREDICTING CARDIAC EVENTS AND CARDIAC-RELATED HOSPITAL ADMISSIONS

Objectives. This study sought to establish the prognostic value of int ravenous dipyridamole technetium-99m (Tc-99m) sestamibi single-photon emission computed tomographic (SPECT) myocardial perfusion imaging. Ba ckground. Optimal management of patients with coronary artery disease involves strategies designed to reduce the risk of myocardial infarcti on and cardiac death. The role of myocardial perfusion imaging using n ewer clinical techniques to determine risk and possible benefit from t herapy has not been evaluated.Methods. Myocardial imaging results were classified as normal or abnormal (fixed or reversible defects; small, moderate or large). Follow-up evaluation of all patients included the occurrence of cardiac death or nonfatal myocardial infarction and oth er cardiac-related hospital admissions. Results. During a mean (+/-SD) follow-up period of 12.8 +/- 6.8 months in 512 patients, 25 had a car diac event. Patients with abnormal perfusion had significantly more ca rdiac events than those with normal perfusion (22 vs, 3, p < 0.01). Pa tients with reversible defects had the highest event rates (8.6%), and those with normal study results had a very low event rate (1.4%). Lar ge defects were strongly associated with more cardiac events and hospi tal admissions than either normal scan results or abnormal results sho wing small defects. Conclusions. Patients with normal study results or a small defect after intravenous dipyridamole Tc-99m sestamibi SPECT imaging had an excellent short-term prognosis. Those with abnormal res ults (reversible or large defect) had an increased risk of subsequent cardiac death, nonfatal myocardial infarction and other cardiac-relate d hospital admissions.