Prinzmetal's angina.

This syndrome is due to focal spasm of an epicardial coronary artery, leading to severe myocardial ischemia. Although it is frequently thought that the spasm occurs in arteries without stenosis, many Prinzmetal patients have spasm adjacent to atheromatous plaques. The exact cause of the spasm has not been well defined, but it may be related to the hypercontractility of the vascular smooth muscle due to vasoconstrictor mitogens, leukotrienes, or serotonin. In some patients, it is a manifestation of a vasospastic disorder and it is associated with migraine, Raynaud's phenomenon, or aspirin-induced asthma. We present a case associated with transient ST-segment depression.