36 patients with previously untreated essential hypertension and left ventricular hypertrophy were treated with a fixed dose combination of atenolol 50 mg and sustained release nifedipine 20 mg once daily for a mean period of 12.1 months. Echocardiography showed a significant decrease after a mean period of 7.9 months in interventricular septal thickness (13.6%, p less than 0.01), posterior wall thickness (12.6%, p less than 0.001) and left ventricular mass index (18.3%). After 12.1 months the reductions were 20.7% (p less than 0.001), 22.5% (p less than 0.001) and 30.8% (p less than 0.001), respectively. Posterior wall thickness was significantly reduced, but left ventricular end-systolic and end-diastolic dimensions and fractional shortening remained unchanged. Treatment significantly reduced resting blood pressure from 153/105 mm Hg to 122/79 mm Hg (p less than 0.001), and exercise blood pressure at 100W from 189/109 to 157/93 mm Hg (p less than 0.001). Thus, nifedipine in combination with atenolol produces significant blood pressure reduction accompanied by regression of left ventricular hypertrophy without noticeable changes in left ventricular function.