Coronary spasm as a cause of coronary thrombosis and myocardial infarction.

A 63-year-old man with an acute anterior myocardial infarction demonstrated an intracoronary nonocclusive thrombus distal to the organic stenosis of the left anterior descending coronary artery. One month after the infarction the thrombus was completely dissolved, and spontaneous and provoked spasm occurred overlying the organic stenosis of the coronary artery. Thus coronary spasm superimposed on the atherosclerotic stenosis was suggested as a cause of the thrombus formation that led to myocardial infarction.