Impact of Smoking and Smoking-Related Parameters on Acetylcholine-Induced Coronary Artery Spasm

ABSTRACT

BACKGROUND AND OBJECTIVES: Smoking has been known to be an independent risk factor of the coronary morbidity induced by coronary artery endothelial dysfunction, but its detailed impact, including the duration and amount of smoking on coronary artery spasm, has not been clarified yet. We investigated the incidence of acetylcholine (Ach)-induced coronary artery spasm according to smoking and the smoking-related parameters. SUBJECTS AND METHODS: The study consisted of 306 patients (163 males, age 56.1+/-11.2 years), without significant coronary artery disease underwent Ach provocation testing by injecting incremental doses of 20, 50 and 100 ug Ach into the left coronary artery. Significant coronary artery spasm was defined as focal or diffuse severe transient luminal narrowing (>75%) with/without chest pain or ST-T change of the EKG. The impact of conventional risk factors, including smoking and the smoking-related parameters, on coronary artery spasm was analyzed. RESULTS: The conventional risk factors of coronary atherosclerosis, including hypertension, DM and hyperlipidemia, were numerically higher in the provocation (+) group, but the differences were not statistically different between the two groups. Only smoking itself was significantly higher in the provocation (+) group whereas the smoking duration, amount and the duration of quitting smoking were not different between the two groups. CONCLUSION: Smoking is known to be an independent risk factor of coronary artery spasm, but smoking-related parameters such as the smoking duration, the amount and the duration of quitting smoking were not associated with coronary artery spasm.