Right Coronary Arterial Spasm Causing Prinzmetal's Variant Angina

Severe spasm of the right coronary artery was documented daring the second of three injections during coronary arteriography in a 42-year-old man with a five-year history of Prinzmetal's variant angina. Only mild atherosclerosis (< 25 percent narrowing) of the artery before and after the spasm was noted. Repeat coronary arteriography two years later confirmed the minimal disease in the right coronary artery, despite continued occasional severe disability from angina. Nitroglycerin invariably relieved the pain and isosorbide dinitrate taken prophylactically has been very effective in preventing episodes of nocturnal angina. These observations support the concept that coronary spasm is one etiology of ischemic pain in variant angina.