Long-term effects of benazepril on ambulatory blood pressure, left ventricular mass, diastolic filling and aortic flow in essential hypertension.

We investigated the long-term effects of benazepril, a new non-sulfydryl angiotensin converting enzyme inhibitor, on ambulatory blood pressure (BP) and left ventricular (LV) anatomy and function in 13 never treated hypertensive patients (mean age 55 years--SD 9). Non-invasive ambulatory BP monitoring (Spacelabs 90202, a reading every 15 min for 24 hours) and standard and pulsed Doppler echocardiography were performed basally and after 12 months of therapy. Echocardiography was performed also at the end of 18th month of treatment. Eleven patients required a single daily dose of benazepril 10 (n = 9) or 20 (n = 2) mg, and two patients of 20 mg plus chlorthalidone 25 mg, to achieve clinical BP control. Average 24 h systolic/diastolic BP was 156/100 mmHg (SD 17/5) basally and 144/90 mmHg (SD 16/7) at the end of the 12th month of treatment (all p less than 0.01), LV mass index was 133 g/m2 basally and 113 g/m2 at the 12th month (p less than 0.01), early transmitral flow velocity (peak E) was 0.43 m/s (SD 0.11) basally and 0.62 (SD 0.13) m/s at the 12th month (p less than 0.01), and late transmitral flow velocity (peak A) did not change [0.67 (SD 0.10) m/s basally and 0.64 (SD 0.11) m/s at the 12th month]. Peak A/peak E ratio decreased from 1.69 (SD 0.57) to 1.31 (SD 0.37) (p less than 0.01). Peak aortic velocity, aortic acceleration time and aortic acceleration did not change. The per cent reduction of LV mass index was more closely related to the reduction of average 24 h systolic (r = 0.66, p = 0.013) and diastolic (r = 0.72, p = 0.005) BP than to the reduction of casual systolic (r = 0.37, p = NS) and diastolic (r = 0.42, p = NS) BP. None of the echocardiographic indices changed between the 12th and 18th month of treatment. In a control group of 13 age- and sex-matched healthy normotensive volunteers who underwent 24 h ambulatory BP monitoring and echocardiography twice, 12 months apart, there were no statistically significant BP or echographic changes. In summary, long-term antihypertensive treatment with benazepril provided and effective 24 h BP control, associated with regression of LV hypertrophy and improvement in LV diastolic filling, without changes in LV systolic function.