Since our initial report in 1984 of six patients with AMI temporally related to cocaine use, we have observed 19 additional patients in whom ischemic chest pain syndromes occurred shortly after intranasal or IV use of cocaine or after smoking the drug. Seventeen patients (89 percent) developed non-Q wave infarction and two had Q-wave infarction. One patient manifested angina with striking ST-segment elevation. None of the patients had diabetes or hypertension, and all but one were cigarette smokers. The serum cholesterol level was 162 +/- 7 mg/dl. Four of the five patients who consented to coronary angiographic studies displayed normal coronary arteries, and one showed proximal stenosis of the right coronary artery. The cold pressor test was performed in seven patients; none had angina or ECG changes induced by cold stimulation. We conclude that T-wave infarction is a common form of an acute cardiac event related to cocaine abuse, and its pathogenesis may involve that of the cocaine-induced coronary vasospasm.