The effects of mibefradil and enalapril on 24-hour blood pressure control and left ventricular mass in patients with mild to moderate hypertension: double-blind, randomized trial

In this prospective, double-blind, monocenter drug trial, 48 primary care patients with mild to moderate essential hypertension were randomized to mibefradil, 50 mg, titrated to 100 mg, or enalapril, 20 mg, titrated to 2 x 20 mg. Ambulatory 24-h blood pressure measurements (ABPM) and echocardiography were performed at baseline and after 12 weeks' treatment. Complete data from 43 patients were analyzed. Mibefradil (n = 22; titration, 13 patients) reduced mean 24-h ABP from 159+/-14/102+/-7 mm Hg to 140+/-10/89+/-7 mm Hg after 12 weeks. Enalapril (n = 21; titration, six patients) reduced baseline ABP from 156+/-12/100+/-9 mm Hg to 140+/-17/89+/-10 mm Hg (12 weeks). Trough-to-peak ratios in DBP were 86% for mibefradil and 75% with enalapril. Left ventricular mass (LVM) decreased from 199+/-65 to 193+/-62 g M-mode modified American Society of Echocardiography (ASE)] and from 184+/-65 to 173+/-50 g (truncated ellipsoid method) after 12 weeks in response to mibefradil (p > 0.2), and from 212+/-50 to 196+/-57 g and from 182+/-39 to 170+/-40 g (mean +/- SD, p < 0.02) with enalapril. Mibefradil matched enalapril in 24-h ABP control. Enalapril reduced LVM significantly after 12 weeks (p < 0.02). Mibefradil did not significantly reduce LVM after 12 weeks.