Left ventricular systolic function after marked reduction of ventricular hypertrophy induced by 5 years' enalapril...

To determine the effects of long-term treatment of essential hypertension with an angiotensin-converting enzyme inhibitor as regards arterial pressure at rest and during exercise, left ventricular mass and functional sequelae.

Twenty-six patients with previously untreated essential hypertension took enalapril 20 mg twice daily for 5 years. Cardiovascular parameters were determined by two-dimensionally guided M-mode echocardiography in a pre-treatment placebo phase, 8 weeks and 1, 3 and 5 years after the start of therapy, and 8 weeks after drugs were discontinued.

Therapy reduced resting arterial pressure from 156/105 to 128/84 mmHg (P < 0.001) and arterial pressure during exercise from 205/113 to 172/94 mmHg (P < 0.0011). After 1, 3 and 5 years' therapy, left ventricular mass index had decreased by 15, 28 and 39% respectively (P < 0.001 in each case). Eight weeks after treatment was halted, arterial pressure at rest and during exercise had returned to pre-treatment values, but decreased left ventricular mass was maintained. Left ventricular pump function had improved after 5 years' treatment, and this improvement was maintained during the 8 weeks without treatment.

Significant reductions in arterial pressure at rest and during exercise were achieved by 8 weeks' treatment with enalapril and maintained during 5 years' further treatment, while a marked reduction in left ventricular mass took place progressively throughout the 5 year period. Reduction of myocardial hypertrophy by enalapril appeared to be beneficial rather than detrimental to cardiac pump performance.