Effects of Antihypertensive Drugs on Central Blood Pressure in Humans: A Preliminary Observation

BACKGROUND: Central blood pressure (BP) is considered a better predictor of cardiovascular events than brachial BP. Modifications of central, beyond brachial BP, can be assessed by pressure amplification, a potential new cardiovascular risk factor. Comparison between drugs' effect on central hemodynamics has been poorly studied. Our aim was to assess the hemodynamic effect of a 12-week treatment with amlodipine 5mg, or candesartan 8mg, or indapamide sustained-release 1.5mg, in comparison with placebo. METHODS: We analyzed 145 out-patients with essential hypertension in primary prevention enrolled in the Natrilix SR Versus Candesartan and Amlodipine in the Reduction of Systolic Blood Pressure in Hypertensive Patients (X-CELLENT) study, a multicenter, randomized, double-blinded, placebo-controlled trial. Arterial stiffness, central BP, pressure amplification, and wave reflection were measured by applanation tonometry. RESULTS: Baseline characteristics of patients were homogeneous between groups. After treatment, we found that active drugs produced similar reduction of both central and peripheral BPs, with no significant interdrug differences (all P < 0.05; excluded peripheral pulse pressure, compared with placebo). Second, amlodipine (1.9% \ub1 15.3%), candesartan (3.0% \ub1 14.6%) and indapamide (4.1% \ub1 14.4%) all increased pulse pressure amplification, but only indapamide was statistically different from placebo (P = 0.02). Finally, no significant changes were observed on pulse wave velocity, heart rate, and augmentation index. CONCLUSIONS: The 3 antihypertensive drugs similarly reduced peripheral and central BP, as compared with placebo, but a significant increase in pulse pressure amplification was obtained only with indapamide, independently of arterial stiffness modifications