There have been no studies of the possibility of reversing the left ventricular hypertrophy (LVH) of chronically hemodialyzed hypertensive uremics (HDH) with long-term antihypertensive therapy. We have measured left ventricular sizes of eight (6 male, 2 female, aged 29 to 61 years) HDH with M-mode echocardiography, before and 12, 18 and 24 months after the start of a combined antihypertensive therapy which included ACE-inhibitors, beta-blockers and calcium-antagonists. Pre-treatment values for mean blood pressure (MBP), 116.6 +/- 2.9 mm Hg, end diastolic diameter (EDD), 62.6 +/- 6.6 mm, interventricular septum (IVS), 14.2 +/- 3.0 mm, and left ventricular mass index (LVMi) , 239 +/- 61 g/m2, were all significantly higher than those for nine sex- and age-matched hemodialyzed normotensive subjects (HDN) with comparable hemoglobin (Hb) levels. During the antihypertensive treatment, both the systolic and diastolic BP decreased steadily (P = 0.0001; P = 0.0003; ANOVA) and significantly by the third month (P < 0.05; P < 0.01), reaching levels comparable to those of the HDN group after 12 months. At this time the LVMi (204 +/- 67) and the IVS (13.1 +/- 2.7), although both significantly lower than baseline, were still higher than in the HDN group, while the EDD was similar. After 24 months, however, both the IVS (12.3 +/- 3.1) and the LVMi (161 +/- 65 ) were no longer different from those of the HDN group. Thus, this study is the first to demonstrate that prolonged antihypertensive therapy with strict blood pressure control is able to considerably reduce the LVH of chronically hemodialyzed uremic patients, indicating the key role of arterial hypertension in inducing pathological growth of the LVM in these subjects.