Effect of carvedilol on coronary flow reserve in patients with hypertensive left-ventricular hypertrophy.

OBJECTIVE Patients with hypertensive left-ventricular hypertrophy (LVH) have lower coronary flow reserve (CFR). Whether carvedilol can improve CFR of patients with hypertensive LVH is unknown. We aimed to investigate the effects of carvedilol on CFR in patients with hypertensive LVH. METHODS Sixty-three patients were randomly divided into two groups for treatment with carvedilol or metoprolol. The peak diastolic coronary flow velocity in the left anterior descending coronary artery at rest and at maximal vasodilation with dipyridamole infusion was recorded by transesophageal echocardiography (TEE), then CFR was calculated at baseline and at the end of 6 months of therapy. Left-ventricular mass index (LVMI) was calculated by 2-D echocardiography. Endothelium-dependent and -independent reactivity of the brachial artery was measured. Levels of plasma endothelin-1 (ET1), nitric oxide (NO) and other metabolites were monitored and analyzed before and after 6-month therapy. RESULTS Both blood pressure and heart rate decreased significantly in the two treatment groups after therapy (p<0.05). With carvedilol treatment, LVMI was lower (p<0.05), endothelium function of the brachial artery was higher (p<0.05), and peak diastolic coronary flow velocity at rest and at maximal vasodilation after dipyridamole infusion was significantly higher (p<0.05) than with metoprolol treatment, which led to a significantly higher CFR (p<0.05). Changes in CFR and LVMI with carvedilol treatment were inversely correlated (R(2)=0.474, p=0.036). With carvedilol treatment, plasma level of ET-1 was lower, but that of NO was significantly higher than with metoprolol treatment (both p<0.05). CONCLUSIONS The CFR of patients with hypertensive LVH but not coronary artery disease could increase with 6-month carvedilol therapy.