Effects of amlodipine and fosinopril on heart rate variability and left ventricular mass in mild-to-moderate essential hypertension

The differences between long-acting dihydropyridines and angiotensin-converting enzyme inhibitors with regard to their long-term effects on 24-h heart rate variability (HRV) and left ventricular (LV) mass are less clear in mild-to-moderate essential hypertension. We studied the long-term effects of amlodipine and fosinopril on 24-h HRV and LV mass in mild-to-moderate essential hypertension. In this study, 27 patients with never treated mild-to-moderate essential hypertension were randomised to receive either amlodipine or fosinopril once daily as monotherapy. At baseline and at the end of the third and sixth months, each of the patients underwent 24-h HRV and ambulatory systolic (SBP) and diastolic (DBP) blood pressure analysis. LV mass index was calculated from echocardiographic examination at baseline and at the end of the sixth month. In amlodipine group (n = 14), 24-h SBP/DBP (mmHg) decreased from 144 +/- 8/94 +/- 4 to 128 +/- 6/83 +/- 3 at the end of the third month and to 125 +/- 5/81 +/- 2 at the end of the sixth month (p < 0.0001). In fosinopril group (n = 13), the respective changes were 143 +/- 9/97 +/- 7, 132 +/- 6/87 +/- 5 and 127 +/- 6/82 +/- 3 (p < 0.0001). At the end of the sixth month, LV mass index (g/m(2)) decreased from 122 +/- 26 to 105 +/- 21 in amlodipine group (p < 0.0001) and from 118 +/- 23 to 101 +/- 14 in fosinopril group (p < 0.0001). There were no significant changes in HRV parameters in both the groups. It was concluded that both drugs caused significant decrease in SBP and DBP, and LV mass in patients with mild-to-moderate essential hypertension did not have significant long-term effects of either amlodipine or fosinopril on 24-h HRV parameters reflecting sympathetic or parasympathetic activity in these patients.