Efficacy of irbesartan on left ventricular mass and arterial stiffness in hypertensive patients

Background: Increased aortic stiffness measured by pulse wave velocity (PWV) and left ventricular hypertrophy (LVH) are independent risk factors of cardiovascular events in hypertensive patients. We have conducted a prospective study to examine the effects of the angiotensin II receptor antagonist (irbesartan) on PWV and LVH in hypertensive patients. Methods: A total of 52 untreated hypertensive patients (age:53.3±8.0 yrs) were enrolled; they had no evidence of associated cardiovascular complications. Blood pressure, heart rate, aortic PWV and left ventricular mass index (LVMI) by 2-D echocardiography were measured at baseline and after irbesartan treatment (150 mg or 300 mg/day) at 12 weeks and 24 weeks. Results: Blood pressure was significantly decreased after 12 weeks and 24 weeks of treatment compared to baseline (SBP: 134.6±13.3 mmHg, 134.0±11.0 mmHg vs 163.7±13.8 mmHg p<0.001, DBP: 86.0±10 mmHg, 83.07 mmHg vs 102.4±9.6 mmHg p<0.001, respectively) without significant change in heart rate. LVMI decreased at 12 weeks and at 24 weeks after treatment compared to baseline (from 145.5±35.1 g/m² at baseline to 137.5±35.4 g/m² at 12 weeks, p=0.017 and 135.3±35.4 g/m² at 24 weeks, p=0.008). Aortic PWV was decreased after irbesartan treatment at 12 weeks (from 9.6±2.8 m/sec to 8.7±3.1 m/sec at 12 weeks, p=0.064) and at 24 weeks (from 9.6±2.9 m/sec to 7.7±2.1 m/sec at 24 weeks, p=0.007). Conclusions: Long-term treatment with irbesartan may reduce arterial stiffness and regression of LVH in hypertensive patients. The pleiotropic effects of irbesartan, further decreasing PWV without change of BP between 12 and 24 weeks of treatment, may have favorable vascular effects on arterial stiffness and LVH.