The aim of this study was to assess the effects of chronic antihypertensive treatment with verapamil and nifendipine on left ventricular (LV) anatomy and function, also in relation to adrenergic activity and beta-adrenergic sensitivity. In fact, it is known that, during antihypertensive treatment, changes of LV mass and function may be affected also by the level of adrenosympathetic tone. Blood pressure (BP), heart rate (HR), plasma catecholamines (pCA), beta-adrenergic responsiveness to isoproterenol (dose that increased HR by 25 beats/min = CD25), LV mass as well as systolic function (2D-guided M-mode echo), at rest and during stress (handgrip test [HG], 30% max, for 3 min), were measured on placebo, after 1 and 6 months of monotherapy with verapamil (VER, 240 mg/day, 9 patients) or nifedipine (NIF, 40 mg/day, 10 patients). Both treatments significantly reduced BP (p less than 0.05 at least). HR, pCA, and cardiac output did not change during treatment with VER, whereas they were slightly but significantly increased during treatment with NIF (p less than 0.05 at least). CD25 was significantly increased during treatment with VER (p less than 0.05) but not during treatment with NIF. Both treatments induced a significant reduction of LV mass after 6 months (p less than 0.01 with VER and p less than 0.05 with NIF).(ABSTRACT TRUNCATED AT 250 WORDS)