To assess left ventricular (LV) structural and functional changes, 45 hypertensive patients were studied by echocardiography after 2 weeks of placebo and 6 months of isradipine monotherapy. Although LV cavity size did not change, LV wall thickness decreased dramatically (P < .0001), producing a significant decrease in LV mass index (from 158 g/m2 to 136 g/m2; P < .0001). In addition, LV fractional shortening (FS) did not change (1.2%; P = NS) whereas the cardiac index increased (6.4%; P = .0007) due to a modest tachycardia accompanied by a reduction in total peripheral resistance (-22.1%; P < .0001). The magnitude of the reduction of LV mass was related to the degree of FS increase (r = -0.70; P < .0001), an indication of beneficial LV remodeling. It can be concluded that isradipine antihypertensive therapy leads to regression of LV hypertrophy without depression of LV pump function.