Effect of antihypertensive monotherapy and combination therapy on arterial distensibility and left ventricular mass

Abstract

Background Angiotensin-converting enzyme (ACE) inhibitors and calcium channel blockers (CCBs) increase arterial compliance and decrease left ventricular mass in hypertensive patients. This study examined whether combined therapy has greater arterial and cardiac effects than doubled doses of the individual drugs. Methods This prospective, randomized, open-label study enrolled 106 patients aged ≥18 years with mild-to-moderate hypertension. Patients were randomized to 5 mg of amlodipine or 20 mg of benazepril for 2 weeks; then, depending on randomization assignment, they were force-titrated to 10 mg of amlodipine or 40 mg of benazepril monotherapy, or to combination amlodipine (5 mg) and benazepril (20 mg) treatment for 22 weeks. Arterial distensibility was assessed using the DynaPulse ambulatory system, and left ventricular mass was assessed by echocardiography. Results Combination therapy (0.71% ± 0.51% mL/mm Hg) increased arterial distensibility more than amlodipine (0.28% ± 0.69% mL/mm Hg; P = .008) or benazepril (0.39% ± 0.62% mL/mm Hg; P = .03) monotherapies. Left ventricular mass decreased more with combination treatment (65 ± 56 g) than with amlodipine (28 ± 4 g; P < .02); the difference from benazepril (42 ± 50 g) was not significant. Conclusions Combined ACE inhibitor and CCB treatment was more efficacious than high doses of the individual agents in increasing arterial compliance and reducing left ventricular mass. These findings indicate that appropriately selected combinations of antihypertensive drugs might have enhanced cardioprotective effects.