A study on coronary hemodynamics during acetylcholine-induced coronary spasm in patients with variant angina: Endothelium-dependent dilation in the resistance vessels

• Published in: Journal of the American College of Cardiology Vol. 19; no. 7; pp. 1426 - 1434
• Main Authors: Okumura, Ken, Yasue, Hirofumi, Matsuyama, Kozaburo, Ogawa, Hisao, Kugiyama, Kiyotaka, Sakaino, Naritsugu, Yamabe, Hiroshige, Morita, Etsuo
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.06.1992; Elsevier Science
• Subjects: Acetylcholine; Angina Pectoris, Variant - physiopathology; Biological and medical sciences; Cardiac Catheterization; Cardiology. Vascular system; Coronary Circulation - physiology; Coronary heart disease; Coronary Vasospasm - chemically induced; Coronary Vessels - physiology; Endothelium, Vascular - physiology; Female; Heart; Humans; Male; Medical sciences; Middle Aged; Nitric Oxide - physiology; Vasoconstriction - drug effects; Vasodilation - drug effects; Vasodilation - physiology; Exercice ECG stress test; Human; Vasomotricity; Coronary artery; Vasoconstriction; Spasm; Cardiovascular disease; Exploration; Acetylcholine; Prinzmetal angina; Hemodynamics; Coronary heart disease
• ISSN: 0735-1097; 1558-3597
• DOI: 10.1016/0735-1097(92)90598-H

The epicardial coronary artery of patients with variant angina is hyperreactive to the constrictive effect of acetylcholine, but it is not known whether the coronary microvasculature also constricts in response to acetylcholine. Incremental doses of acetylcholine were injected into the left coronary artery of 57 patients with variant angina and with spasm in this artery. By measuring coronary sinus blood flow, coronary hemodynamic status just before angiographic documentation of spasm was examined. Acetylcholine induced spasm in the left coronary artery in all patients. It also decreased the diameter of the nonspasm artery by 36 ± 19% from baseline. For all patients, coronary sinus blood flow was 89 ± 38 ml/min at baseline and increased to 104 ± 61 ml/min during an acetylcholine-induced anginal attack (p < 0.01). In 10 patients with spasm in both the left anterior descending and left circumflex arteries (that is, multivessel spasm), corortary sinus blood flow decreased from 84 ± 21 to 52 ± 26 ml/min (p < 0.01). In the other 47 patients with spasm in only one of these two arteries (that is, single-vessel spasm), coronary sinus blood flow increased from 90 ± 41 to 115 ± 61 ml/min (p < 0.01) without change in the rate-pressure product. It is concluded that in patients with variant angina, acetylcholine induces spasm and constriction in the epicardial coronary artery, whereas it dilates the resistance vessels presumably through the release of the endothelium-dependent relaxing factor.