Irbesartan and atenolol improve diastolic function in patients with hypertensive left ventricular hypertrophy

OBJECTIVES AND DESIGN: An abnormal diastolic filling is common in hypertensive left ventricular (LV) hypertrophy, a condition that may lead to heart failure and death. The renin-angiotensin-aldosterone system has been implicated in the development of LV hypertrophy. This study examines the effects of 48 weeks of double-blind treatment with the AT1 receptor blocker irbesartan and the beta-blocker atenolol on diastolic function. METHODS: Diastolic function was evaluated in 115 hypertensive patients with LV hypertrophy by Doppler echocardiography mitral inflow velocities calculated from the peak of early (E) and peak of late (A) diastolic velocities (E/A ratio), the E-wave deceleration time, the isovolumic relaxation time, the pulmonary venous flow velocity, and by the atrioventricular valve plane displacement method. RESULTS: By similar reductions in blood pressure both groups progressively reduced the LV mass index, with a greater reduction in the irbesartan group (P = 0.024). Diastolic function was improved similarly by irbesartan and atenolol; for example, the E/A ratio by 12 and 14% (P = 0.022 and P < 0.001), and the pulmonary venous flow velocity by 10 and 7% (P = 0.036 and P = 0.001), respectively. The isovolumic relaxation time was improved by irbesartan (P = 0.040) only, and was related to changes in LV geometry (P < 0.001). For atenolol, improvement in diastolic function was associated only with the reduction in blood pressure (P = 0.048). An improvement in diastolic function appeared greater in concentric LV hypertrophy than in eccentric LV hypertrophy. CONCLUSIONS: Treatment based on atenolol or irbesartan improves diastolic function in patients with hypertensive LV hypertrophy to the same degree, but through different mechanisms.