Comparison of ECG Findings between Hypertrophic Obstructive Cardiomyopathy and Hypertension with Disproportionate Septal Thickening

ABSTRACT

Electrocardiographic findings in 18 cases of hypertrophic obstructive cardiomyopathy(HOCM) were compared with those in 20 hypertensives with disproportinate septal hypertrophy(DSH) and in 20 normal controls. In conventional 12 leads electrocardiograms, abmormal Q waves were seen only in 6 cases of HOCM and none in the remadinder. The R waves were tallest in leads V4 in 6 cases(33%) of HOCM, 3(15%) hypertensives with DSH, and 4(20%) of the controls. The correlations of the QRS voltages with echocardiographically measured left ventricular dimension, interventricular septal thickness and left ventricular mass were significant in the hypertensives with DST and normal controls, but insignificant in patients with HOCM. We conclude that these electrocardiographic differences in patients with HOCM from the others would be caused by uneven distribution of hypertrophied muscle mass in the left ventricule and/or by the altered depolarization in hypertrophied cardiac muscles.