Background: There has been no report of ECG changes during anginal attacks in patients with coexistent hypertrophic cardiomyopathy (HCM) and vasospastic angina.
Study objectives: To elucidate the change in ST-segment during anginal attacks in patients with coexistent HCM and vasospastic angina (the HCM group) in comparison with that of patients with vasospastic angina and no left ventricular hypertrophy (the non-HCM group).
Design: Retrospective study.
Patients: Twelve patients in the HCM group, and 28 patients in the non-HCM group.
Measurements: The direction of ST segment shift, either ST-segment elevation or depression, on the ECGs recorded during vasospastic anginal attacks with severe vasoconstriction in the epicardial coronary artery after intracoronary injection of acetylcholine.
Results: Age, male gender, and distribution of coronary arteries in which the vasospasm occurred were similar between the two groups. Collateral circulation to the affected arteries was absent in all the study patients. The prevalence of anginal attacks associated with ST-segment elevation was 2.7 times higher in the non-HCM group than in the HCM group (51. 5% [17 of 33 attacks] vs 18.8% [3 of 16 attacks], respectively; p = 0.03).
Conclusions: In the HCM group, myocardial ischemia associated with a transmural injury pattern seen on the ECG, which is represented as ST-segment elevation, seldom develops during vasospastic anginal attacks because of marked left ventricular hypertrophy.