Chronic left ventricular hypertrophy (LVH) is associated with depressed contractile performance, abnormal compliance of the chamber, and ultimately, the development of a left ventricular failure. Thus the presence of LVH carries a particularly ominous prognosis in patients with essential hypertension. Finally, regression of LVH appears to be a worthwhile goal of an antihypertensive therapy along with blood pressure control. Of particular importance, is whether the functional derangements associated with hypertrophy will also be reversed. The present study was undertaken to determine whether antihypertensive therapy reduced ventricular mass, and whether these changes were accompanied by improved diastolic function. 47 patients with mild-to-moderate essential hypertension were divided into two groups. Group I--included 21 patients whose blood pressure responded to nifedipine monotherapy. Group II--included 26 patients whose normalization of blood pressure required combined therapy with nifedipine and metoprolol. 40 healthy volunteers comprised a control group. To assess the effects of antihypertensive therapy on the heart, left ventricular mas (LVM), systolic and diastolic function, by M-mode, 2-D and pulsed wave Doppler echocardiography had been evaluated. Measurements were performed before therapy and every 3rd month during first year, and every 40th month during the second year of observation. RESULTS. At baseline all hypertensive patients had significantly increased LVM compared to the controls. Indexes of systolic function in studied patients were normal, while indexes of LV diastolic filling were significantly abnormal compared to the controls. In the group treated with nifedipine, starting from the 9th month of observation, small but significant decrease in posterior wall thickness was noted but LVM did not change during the whole time of the observation. Similarly, there was no significant change in indexes of left ventricular diastolic filling. Contrary to patients treated with nifedipine, in group of patients treated with combination of nifedipine and metoprolol, significant reduction of LVM and improvement of LV diastolic filling was observed. Of particular interest was the fact, that improvement in diastolic, performance appeared earlier, and preceded regression of LVM. Most striking was the improvement in Ev/Av ratio which increased by 16% after 6 months and by 35% after 24 months of the therapy. CONCLUSION. 1. Combined therapy with nifedipine and metoprolol contrary to monotherapy with nifedipine alone, results in the regression of left ventricular mass and the improvement of left ventricular diastolic function. 2. Improvement of left ventricular diastolic function appears earlier, preceding the regression of left ventricular hypertrophy.