Relationship between the regression of left ventricular hypertrophy and the changes in circadian blood pressure after long-term treatment with enalapril in hypertensive patients.

The ambulatory blood pressure (BP) was recorded for 24 hours in 28 untreated hypertensive patients, and mean values of systolic (SBP) and diastolic BP (DBP) were measured over 24 hours, during the day-time (6:00 to 19:30), and during the night-time (20:00 to 5:30). M-mode echocardiography was performed and several parameters of left ventricular size were calculated. In addition, 13 men of 18 patients with left ventricular hypertrophy (LVH) received long-term treatment with enalapril, and ambulatory BP monitoring and echocardiographic measurement were performed in 10 of these patients 6 months after active treatment ended. In all 28 patients, left ventricular mass index (LVMI) was significantly related to 24-hour, day-time and night-time SBP. Other parameters of hypertrophy were correlated with 24-hour and/or night-time BP, but not with day-time BP. In patients with LVH, night-time DBP was significantly higher and the night-time decline in DBP was significantly less than in those without LVH. The 6-month treatment with enalapril clearly decreased casual and ambulatory BP and reduced LVMI. The reduction of LVMI was strongly correlated with the decrease in night-time SBP and DBP compared with the decrease in day-time BP. These observations indicate that LVH is related to 24-hour BP (especially night-time BP) and that the regression of this condition may be related to a decline in night-time BP.