Effects of lisinopril vs hydralazine on left ventricular hypertrophy and ambulatory blood pressure monitoring in essential hypertension

In order to compare the long-term effects on ambulatory blood pressure and left ventricular hypertrophy of hydralazine and lisinopril we studied 30 patients, all males, still hypertensive (diastolic blood pressure > or = 95 mm Hg) despite combined beta-blocker/diuretic therapy and with echocardiographic evidence of left ventricular hypertrophy (left ventricular mass index > or = 1.31 g.m(-1)). They wer randomized to receive hydralazine slow release 50 mg/ chlorthalidone 12.5 mg) for 6 months. Casual blood pressure, non-invasive ambulatory blood pressure monitoring (ABPM), M-mode echocardiogram, plasma renin activity and plasma catecholamines were evaluated before the randomization and after 6 months of treatment. Both drugs significantly reduced casual as well as daytime systolic and diastolic blood pressure, without statistical differences between the two treatments. Lisinopril was significantly more effective than hydralazine in reducing night-time systolic and diastolic blood pressure. Plasma norepinephrine was significantly reduced by lisinopril and increased by hydralazine. Left ventricular mass was significantly reduced by lisinopril but not by hydralazine. The results of linear regression and multiple regression analysis suggested that the lisinopril-induced decrease in both day- and night-time blood pressure might account for the regression of left ventricular hypertrophy, whereas the lack of left ventricular hypertrophy regression during hydralazine treatment could be due mainly to the reflex sympathetic activation induced by the drug.