Possible beneficial effect of olmesartan medoxomil on left atrial function in patients with hypertension : noninvasive assessment by acoustic quantification

Hypertension alters the diastolic properties of the left ventricle and results in deterioration in the structure and function of the left atrium. We aimed to evaluate whether olmesartan medoxomil has an effect on left atrial function in hypertensive patients.

Fifty hypertensive patients and 20 controls were included in the study. Hypertensive patients were treated with olmesartan medoxomil for 8 weeks. Before and after treatment, study participants were examined by acoustic quantification and tissue Doppler imaging. Left atrial reservoir function was assessed by end-diastolic volume (EDV), end-systolic volume (ESV), reservoir volume (RV) and peak filling rate (PFR). Left atrial booster pump function was assessed by atrial emptying volume (AEV), atrial emptying fraction (AEF) and peak atrial emptying rate (PAER). Left atrial conduit function was assessed by rapid emptying volume (REV), rapid emptying fraction (REF), REV/AEV ratio, and the ratio of peak rapid emptying rate and PAER (PRER/PAER).

Atrial RV and PFR were significantly increased in hypertensive subjects (48.30 +/- 19.28 mL vs 34.35 +/- 14.26 mL, p < 0.001; 267.26 +/- 126.52 mL/s vs 206.81 +/- 107.17 mL/s, p < 0.05) compared with controls, while the REV/AEV ratio was decreased in hypertensive patients compared with controls (2.86 +/- 0.85 vs 3.69 +/- 2.13, p < 0.001). After therapy with olmesartan medoxomil, atrial RV (48.30 +/- 19.28 mL vs 40.50 +/- 17.59 mL) and PFR decreased (267.26 +/- 126.52 mL/s vs 220.40 +/- 108.56 mL/s, p < 0.05) and the REV/AEV ratio increased (2.86 +/- 0.85 vs 3.14 +/- 0.43, p < 0.05) in hypertensive patients.

Our novel findings indicate that left atrial function is impaired in hypertensive patients, and that olmesartan medoxomil can improve left atrial function in this context. Our study also showed that acoustic quantification is useful for non-invasive evaluation of the benefits of treatment on left atrial function.