Coronary artery spasm.

Coronary artery spasm is a transient reduction in lumen diameter of an epicardial coronary artery of sufficient degree to produce objective evidence of myocardial ischemia in the absence of any significant increase in heart rate or blood pressure. In this article are summarized pathophysiological observations, the coronary angiographic anatomy of patients with coronary spasm, etiologic considerations, methods to provoke coronary artery artery spasm and their clinical usefulness, the role of coronary artery spasm in patients with clinical angina pectoris and myocardial infarction, and finally, the role of coronary artery spasm in patients undergoing coronary artery surgery.