Coronary artery slow flow associated with angina pectoris and hypotension--a case report.

A 56-year-old woman with a history of angina pectoris developed substernal chest pressure and hypotension during coronary angiography. Her baseline coronary angiogram appeared normal. During this episode, injection of contrast medium into the left coronary artery demonstrated coronary artery slow flow in the left anterior descending artery and branches of the circumflex coronary artery, which normalized following the sublingual administration of nitroglycerin. There were no focal areas of coronary artery spasm. This phenomenon may represent a heretofore undescribed mechanism for myocardial ischemia and its sequelae.