The clinical and angiographic findings of 17 resuscitated victims of exercise-related sudden ischemic death are reported in an attempt to elucidate the mechanism(s) of these deaths. Ten survivors developed cardiac arrest during or after sporting activities (group A) and 7 others during or after an exercise stress test (group B). There were 15 men and 2 women. The mean age of group A was 46 years and of group B 55 years. Coronary risk factors, as well as previous angina and myocardial infarction, were more frequent in group B. Only 3 of the 17 survivors had anginal symptoms before sudden death. Sudden death in group A was associated with acute myocardial infarction in 8 and unstable angina in 2 and was associated in group B with acute myocardial infarction in 2, unstable angina in 3 and silent ischemia in 2. Coronary angiography was acutely performed in 15 patients. In most patients the ischemia-related coronary artery was totally or subtotally occluded. Clinical and angiographic findings indicate that exercise-related sudden ischemic death was due to an acute coronary event--in most cases unexpected and unpredictable. It is suggested that exercise-induced intracoronary changes were probably responsible for the development of acute coronary (sub)occlusion and sudden death.