Tissue Velocity Echocardiography Shows Early Improvement in Diastolic Function With Irbesartan and Atenolol Therapy in Patients With Hypertensive Left Ventricular Hypertrophy: Results From the Swedish Irbesartan Left Ventricular Hypertrophy Investigation vs Atenolol (SILVHIA)

Abstract

Abnormal diastolic function is common in hypertensive left ventricular hypertrophy (LVH). Early identification and treatment may prevent future cardiovascular events. We examined 58 hypertensive patients with LVH, 38 with hypertension but no LVH, and 38 normotensive subjects. The effects of the AT1 receptor blocker irbesartan and the beta1 blocker atenolol on diastolic function during 48 weeks of treatment were evaluated in the LVH group by tissue velocity echocardiography (TVE). We measured basal septal and lateral wall velocities of early (Em) and late (Am) diastolic myocardial wall motion, Em velocity deceleration time (E-decm), and isovolumic relaxation time (IVRTm). For comparison, diastolic function was assessed by conventional mitral pulse wave Doppler echocardiography. Diastolic function was impaired in both hypertensive groups. Irbesartan and atenolol (week 48, septal wall) improved IVRTm (-44%, P<.001, and -19%, P<.001; P<or=.001 between groups), E-decm (+56%, P<.001, and +53%, P<.001), and Em/Am (+11%, P=.396, and +20%, P=.010). Only irbesartan improved E/Em (-4%, P=.052 v +2%, P=.041). For irbesartan, relative changes in IVRTm and in septum thickness were related (P=.017), whereas relative changes in the Em/Am ratio and in heart rate were related for atenolol (P=.027). Alterations in diastolic dysfunction were greater and detected earlier with TVE than with conventional echocardiography. The TVE is more sensitive than conventional echocardiography in detecting alterations in diastolic function. Both irbesartan and atenolol improve diastolic function, but through different mechanisms. The improvement in IVRTm was greater with irbesartan, and only irbesartan improved E/Em. This may have implications on the treatment of high risk hypertensive patients.