Coronary Artery Spasm Producing Prinzmetal's Angina and Myocardial Infarction in the Absence of Coronary

This report describes a patient with typical Prinzmetal's variant angina, myocardial infarction, ventricular arrhythmias, and complete heart block who had a single left coronary artery and no coronary atherosclerosis. At the time of coronary arteriography, spasm was documented in the midportion of the dominant circumflex vessel. Saphenous vein bypass grafting was accom- plished to the distal circumflex artery with temporary relief of all symptoms. There was, however, a recurrence of typical Prinzmetal's variant angina, and on restudy the vein graft anastomosis was seen to be closed at the area where competitive flow would be expected. Saphenous vein bypass grafting appears not to be the treatment of choice in patients with Prinzmetal's variant angina in the absence of high-grade atherosclerotic lesions. lthough vasospasm is frequently seen in normal coronary arteries at the time of arteriography (3), the role of spasm in producing A symptomatic myocardial ischemia at other times has not been clearly shown. Numerous cases have been reported of myocardial infarction without coronary atherosclerosis. In a recent report (2), Prinzmetal's variant angina occurring at rest and associated with ST-segment elevation is described in patients without coronary atherosclerosis. Could coronary artery spasm be the explanation for some of these episodes? Coronary artery bypass grafting has recently been advocated for patients with Prinzmetal's angina and significant atherosclerotic lesions (6). The purpose of this paper is to report a case that gives strong support to the idea that coronary artery spasm may be responsible for acute myocardial infarction in the absence of