140: Left atrial remodeling after successful ballon mitral valvuloplasty

Abstract

Left atrium (LA) remodeling has a crucial adverse impact on outcome and prognosis in mitral stenosis. Few studies have reported the effect of balloon mitral valvuloplasty (BMV) on LA volume and function. The aim of this study was to assess the evolution of LA volume and compliance 1 and 6 months after successful BMV in patients in sinus rhythm. 95 consecutive patients (70% women; age 31±8 years; range 19-45) with severe mitral stenosis (mitral valve area ≤14 cm(2)) who underwent successful BMV were included prospectively. Using-dimensional echocardiography, and according to the prolate ellipse method, LA volume, area and compliance (The maximum and the minimum LA volume were calculated from apical four- and two-chamber zoomed views of the LA, using the biplane method of discs. The difference between maximum and minimum LA volume divided by the minimum LA volume was used as an index of atrial compliance) were determined before BMV, and 1 month and 6 months after BMV. LV global systolic function was evaluated by EF, by the biplane Simpson method. Longitudinal left ventricular annular velocities were quantified by spectral pulsed wave Doppler tissue velocity imaging Mitral valve area increased from 0.88±0.2 to 1.8±0.26 cm(2) (P<0.0001). Mean mitral valve gradient (MVG) decreased from 14±6 to 6±2 mmHg (P<0.0001) immediately after BMV. Indexed LA volume fell from 66±14 to 52±12 mL/m (2) (P=0.02) after BMV and to 45±13 mL/m (2) at 6 month (P<0.01) and an increase 0f the atrial index. Only patients with a median LA volume ≥55 mL/m (2) before BMV had a significant reduction in LA volume (P=0.0001). Decrease in LA volume was correlated with decreases in PA-RV peak diastolic gradient (r=0.45, P=0.008) and MVG (r=0.35, P=0.04). In patients with mitral stenosis in sinus rhythm, successful BMV results in an immediate decrease in LA volume. This reduction, maximal immediately after BMV, correlates with decreases in MVG and PA-RV peak diastolic gradient, and is significant only when LA volume before BMV is severely enlarged.