PREDICTION OF LATE CARDIAC EVENTS BY DIPYRIDAMOLE-THALLIUM SCINTIGRAPHY IN PATIENTS WITH INTERMITTENT CLAUDICATION AND OCCULT CORONARY-ARTERY DISEASE

Concomitant coronary artery disease often occurs in patients with peri pheral vascular disease, but it may be asymptomatic. Despite being asy mptomatic, cardiovascular events are the main source of morbidity and mortality in this group of patients, Dipyridamole thallium scintigraph y has been shown to be of prognostic value in patients with peripheral vascular disease and symptomatic coronary artery disease, but its eff ect on the long-term outcome in the asymptomatic group of patients is less defined. Eighty-four consecutive patients with peripheral vascula r disease and pro symptoms of coronary artery disease were therefore e valuated by clinical assessment, dipyridamole thallium imaging, radion uclide ventriculography, and cardiac catheterization and followed for a mean of 66 months, Abnormal perfusion patterns were found on thalliu m scintigraphy in 48 patients (57%); fixed, mixed, and reversible defe cts were present in 14 (17%), 11 (13%), and 23 (27%) patients, respect ively. Significant coronary artery disease was present in 52 patients (69%) and mean left ventricular ejection fraction was 44%. During the follow-up period, 23 patients had a cardiac event (nonfatal myocardial infarction or cardiac death). Univariate analysis of 15 clinical, sci ntigraphic, radionuclide, and angiographic variables revealed that age , angiographic extent of coronary artery disease, and an abnormal thal lium scan were significant predictors of subsequent cardiac events. Mu ltivariate stepwise logistic regression analyses selected fixed and mi xed thallium defects and diffuse coronary artery disease as the only s ignificant independent predictors of outcome. Thus, the present study shows the value of dipyridamole thallium scintigraphy as a valuable pr ognostic indicator for long-term event-free survival in a cohort of pa tients with peripheral vascular disease and no history or symptoms of coronary artery disease.