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Objective: Antihypertensive agents of different classes may have profound effects on heart rate variability (HRV). HRV changes in patients with essential hypertension were evaluated after pharmacological treatment by time domain (TD) analysis on 24-hour electrocardiographic (ECG) recordings. Design and Patients: In this randomised block single-blind trial, 45 patients with essential hypertension were randomly assigned to either atenolol, a cardioselective β-blocker, carvedilol, a β-blocker with vasodilator properties, or lacidipine, a long-acting dihydropyridine calcium antagonist, and underwent simultaneous 24-hour ECG and ambulatory blood pressure monitoring before and after 8 weeks' treatment. TD measures were calculated. Results: During treatment with atenolol and carvedilol, the 24-hour average normal RR [mean normal to normal intervals (NN)] was significantly increased (p < 0.0001 and p < 0.0002, respectively). Measures of tonic vagal activity were increased significantly only with atenolol: increase of 64.3% for the percentage of differences >50msec between adjacent NN intervals and increase of 45.2% for root mean square successive differences. By contrast, standard deviations (SD) of all NN over a 24-hour period and SD of means of 5-minute blocks of NN related to total and diurnal HRV were significantly increased by lacidipine (13.4 and 18.9%, respectively) and decreased by carvedilol (-12.0% and -22.0%, respectively) but not significantly modified by atenolol. Modifications in TD parameters were unrelated to the degree of 24-hour blood pressure reduction. Conclusions: HRV, assessed by TD, is modified differently according to the specific type of antihypertensive monotherapy used. These modifications could have prognostic importance. TD measures of HRV may be a practical and powerful instrument for the evaluation of the effect of antihypertensive drugs. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the differential response in left ventricular mass and resistive index (RI) of renal and carotid arteries in mild to moderate essential hypertensive patients after 1 year of ACE inhibitor therapy. Twenty-six patients (mean age 42.9 ± 10.9 years) underwent 24-hour ambulatory blood pressure monitoring, echocardiography and renal and carotid echo-Doppler (by measuring RI, as an expression of arterial impedance) after a placebo period and 12 months of fosinopril treatment (20 mg/day). Our study showed a significant decrease in 24-hour BP (p < 0.05), left cardiac mass (p < 0.05) and RI of common carotid and hilum renal arteries (p < 0.05). In contrast, there were no significant reductions in the interlobar renal RI (as an expression of unchanged intrarenal resistance) and in the internal carotid artery RI. While the 24-hour BP decrease was strongly correlated with the left cardiac mass modifications (r = 0.73, p < 0.005), no significant relationship was observed with the renal and carotid artery parameters. In conclusion, the present study demonstrated that long-term treatment with fosinopril produced a differential response in left ventricular mass and arterial RI in patients with mild to moderate essential hypertension. In addition, the arterial impedance modifications of common carotid and hilum renal artery were largely unrelated to the 24-hour BP reduction. [ABSTRACT FROM AUTHOR]