Effect of hypertension on asymmetrical septal hypertrophy: an echocardiographic study

The effect of hypertension on asymmetrical septal hypertrophy was studied by echocardiography to differentiate idiopathic asymmetrical septal hypertrophy (ASH) from ASH with hypertension. One hundred eight patients with ASH proven by echocardiography were categorized in two groups; 53 patients with hypertension (greater than 160 systolic, greater than 95 diastolic) (hypertensive group: HT) and 55 patients with normal blood pressure (normotensive group: NT). Septal hypertrophy was classified as mid-portion (M-type), diffuse (D-type), and basal (B-type) hypertrophy by the long-axis view, and also diffuse (I-type), anterolateral (II-type), anteroseptal (III-type), and anterior septal (IV-type) by the short-axis view, respectively. Endomyocardial biopsy and left ventriculography were performed in 50 patients (18 hypertensives and 32 normotensives). In the hypertensive group, 45%, 30%, and 25% of cases had diffuse, basal and mid-portion hypertrophy, respectively. There was no case in the basal hypertrophy whose biopsy findings were compatible with hypertrophic cardiomyopathy. In the normotensive group, 78% and 22% of patients had midportion and diffuse hypertrophy, respectively, but none of them had the basal hypertrophy. Type IV was seen in only six patients in the normotensive group.