[Regression of myocardial hypertrophy in hypertensives on chronic beta-receptor block].

25 patients (24 males, 1 female; mean age 43.7 years), with previously untreated essential hypertension and echocardiographically proven left-ventricular hypertrophy, received metoprolol 200 mg daily over a period of 12.7 months, five of them additionally hydrochlorothiazide 25 mg. After four weeks, resting recumbent blood pressure had decreased from 157 +/- 18 systolic and 106 +/- 9 diastolic to 128 +/- 11 and 85 +/- 9, respectively; after 12.7 months to 123 +/- 12 and 83 +/- 8 mm Hg (P less than 0.001). On 100 W exercise the blood pressure fell from initially 206 +/- 13 and 117 +/- 9 168 +/- 12 and 97 +/- 9, after 12.7 months to 170 +/- 14 and 98 +/- 9 mm Hg. Left-ventricular mass fell from 147.0 +/- 26 g/m2 by 14% after 6.1 months, by 22.5% after 12.7 months (P less than 0.001). While the left-ventricular diameter in enddiastole and endsystole remained unchanged, septal thickness decreased from 15.5 +/- 2.1 to 14.2 +/- 2.2 mm after 6.1 months and 13.1 +/- 1.9 mm after 12.7 months (reduction of 15.5%). The corresponding values for the left-ventricular posterior wall were 11.9 +/- 1.6 before and 10.8 +/- 1.8 after 6.1 months and 10.1 +/- 1.4 mm after 12.7 months (reduction of 16%). Thus long-term administration of metoprolol resulted in a significant reduction in myocardial hypertrophy without impairment of ventricular function.