The effect of coronary vasospasm on the direction of ST-segment deviation in patients with both hypertrophic cardiomyopathy and vasospastic angina

Background: There has been no report of ECG changes during anginal attacks in patients with coexistent hypertrophic cardiomyopathy (HCV) and vasospast ic angina. Study objectives: To elucidate the change in ST-segment during anginal atta cks in patients with coexistent HCM and vasospastic angina (the HCM group) in comparison with that of patients with vasospastic angina and no left ven tricular hypertrophy (the non-HCM group). Design: Retrospective study, Patients: Twelve patients in the HCM group, an d 28 patients in the non-HCM I group, Measurements: The direction of ST seg ment shift, either ST-segment elevation or depression, on the ECGs recorded during vasospastic anginal attacks with severe vasoconstriction in the epi cardial coronary artery after intracoronary injection of acetylcholine. Results: Age, male gender, and distribution of coronary arteries in which t he vasospasm occurred were similar between the two groups, Collateral circu lation to the affected arteries was absent in all the study patients, The p revalence of anginal attacks associated,vith ST-segment elevation was 2.7 t imes higher in the non-HCM group than in the HCM group (51.5% [17 of 33 att acks] vs 18.8% [3 of 16 attacks], respectively; p = 0.03). Conclusions: In the HCM group, myocardial ischemia associated with a transm ural injury pattern seen on the EGG, which is represented as ST-segment ele vation, seldom develops during vasospastic anginal attacks because of marke d left ventricular hypertrophy.