Systolic time intervals and echocardiographic findings in borderline hypertension.

Systolic time intervals, echocardiographic dimensions and hemodynamic parameters were determined in 42 borderline hypertensive patients with high cardiac output and 33 normal subjects. In borderline hypertensive patients, the preejection period was significantly reduced (P less than 0.001) and was negatively correlated to cardiac index (P less than 0.001). The interventricular septum thickness (IVS) was significantly increased (P less than 0.001) while the posterior wall thickness (PW) was within normal values. The IVS/PW ratio was significantly elevated (P less than 0.001) and was correlated negatively with the cardiac index (P less than 0.01) and positively with the preejection period (P less than 0.01). These findings suggest that (i) myocardial hypertrophy and increased left ventricular performance exist in borderline hypertension, (ii) myocardial contractility is reduced as myocardial hypertrophy increases.