The Characteristics and Risk Factors of Coronary Artery Spasm Induced by Acetylcholine

ABSTRACT

BACKGROUND: Although there have been many studies on the risk factors for coronary artery disease, the etiology and risk factor of coronary artery spasm has not yet been determined. The objective of this study was to examine the risk factors for coronary vasospasm through a comparison of patients with angiographically determined vasospastic angina and patients without vasospasm and normal coronary artery. METHODS: Intracoronary injection of acetylcholine in order (20microg, 50microg, 100microg) were administered to all patients (Total 8134 males, 47 females mean age 50 years) who had a history of chest pain with normal or near normal coronary arteriographic fingings. After documentation of vasospasm in major epicardial coronary arteries by acetylcholine (Ach)-provocated dcoronary angiography, various risk factors (smoking, hypertension, diabetes, drinking and hyperlipidemia) were compared between patients with vasospasm and patients without vaspasm. RESULTS: 24 patients showed significant luminal narrowing (> or =75%)(Vasospasm group) and 57 patients showed no significant change (Control). Vasospasm group were suffered from typical chest pain in 92% of patients but control complained typical chest pain in 51% of subjects. The sites of vasoconstriction induced by Ach were LAD (11 cases), LCX (4 cases), RCA (11 cases) and vasoconstriction occurred 2 vessels (LAD and LCx) at the same time in two cases. The amount of Ach to provocate vasoconstriction was 20~50microg (90%) and there were no difference between left and right coronary arteries. The ratio of smoker was more frequent in the vasospasm group than control (58.3% vs 30.4%, p=0.046). But total cholesterol, low density lipoprotein, high density lipoprotein, triglycerides, apolipoprotein A, apolipoprotein B, lipoprotein (a), diabetes and body mass index, drinking were not statistically significant between two groups. CONCLUSION: Smoking appears to be a major risk factor for vasospastic angina by endotheilal dysfunction without significant coronary artery narrowing. But other fisk for coronary artery disease may not contribute to coronary vasospasm.