Frequency of provoked coronary vasospasm in patients undergoing coronary arteriography with spasm provocation test of acetylcholine

This study examines the incidence of spasm by intracoronary injection of acetylcholine in Japanese patients who underwent coronary angiography. The subjects were 685 consecutive patients (477 men, mean age 63.2 ± 7.5 years) who were studied with an acetylcholine test. Acetylcholine was injected in incremental doses of 20, 50, and 80 μg into the right coronary artery and 20, 50, and 100 μg into the left coronary artery. Spasm was defined as total or subtotal occlusion. Coronary vasospasm was determined in 221 patients (32.3%). Spasm occurred often during effort and rest in patients with angina (25 of 51, 49.0%), exertional angina (25 of 74, 33.8%), recent myocardial infarction (30 of 80, 37.5%), healed myocardial infarction (14 of 37, 37.8%), and especially in patients with rest angina (83 of 124, 66.9%), whereas spasm was relatively uncommon in patients with nonischemic heart disease (23 of 252, 9.1%). Spasm was superimposed on significant atherosclerotic lesions in 35.9% of patients as well as on nonfixed atherosclerotic lesions in 30.8% of patients. We conclude that >9% of Japanese patients may have coronary vasospasm with intracoronary injection of acetylcholine and recommend the provocation test for evaluating coronary vasospasm if coronary angiography is undertaken.