Cardiac involvement in adolescent hypertension. Echocardiographic determination of myocardial hypertrophy.

We measured left ventricular chamber dimension and wall thickness using M-mode echocardiography in 61 adolescents with systolic or diastolic blood pressures above the 90th percentile for age and sex and in 49 normotensive adolescents. Left ventricular posterior wall and ventricular septal thickness indexed to body surface area were significantly greater (p less than 0.001) in the hypertensive group than in the normotensive controls. Left ventricular chamber diastolic and systolic dimensions were not different in the hypertensive group when compared to normotensive adolescents with comparable body size. Left ventricular diastolic and systolic volumes as well as left ventricular function did not differ between the hypertensive and control groups. Calculated parameters of left ventricular hypertrophy, namely, the radius-to-wall-thickness ratio, cross-sectional muscle area, and left ventricular mass, in the hypertensive adolescents were all significantly different (p less than 0.001) from those in the control groups. The finding of myocardial hypertrophy in young, mildly hypertensive subjects suggests early myocardial involvement in the hypertensive process.