Left atrial electromechanical conduction time predicts atrial fibrillation in patients with mitral stenosis: a 5-year follow-up speckle-tracking echocardiography study
BACKGROUND The aim of this study was to assess systolic left atrial (LA) reservoir function in patients with mitral stenosis (MS) using two-dimensional (2D) strain (ε) and strain rate imaging and its prognostic value in predicting atrial fibrillation (AF) at 4-year follow-up. METHODS One hundred one asymptomatic patients with pure rheumatic MS and 70 healthy controls were evaluated using standard Doppler echocardiography (mitral valve area, mean gradient, systolic pulmonary pressure, LA width, LA volumes, and LA ejection fraction) and 2D speckle-tracking. RESULTS LA width, volumes, and systolic pulmonary pressure were significantly increased (P < .0001), and LA 2D ε and strain rate were significantly impaired in patients with MS (P < .0001). At 4-year follow-up, 20 patients (20%) showed AF on standard electrocardiography or 24-hour Holter electrocardiography. Patients with MS who had AF were older than those who did not, without significant differences in LA dimensions, volumes, ejection fraction, and compliance index. Instead, atrial myocardial systolic 2D ε was significantly impaired in patients with events. On multivariate analysis (age, LA volume, planimetric mitral area, average annular Ea, and LA strain) the best predictor of AF was average LA peak systolic ε (coefficient, 0.43; SE, 0.098; P < .01), with an area under the receiver operating characteristic curve of 0.761 (SE, 0.085; 95% confidence interval, 0.587-0.888, P = .002) for a cutoff value of 17.4%. CONCLUSIONS The results of 2D ε imaging are abnormal in patients with asymptomatic MS and predict AF at 4-year follow-up.