Atrioventricular reverse remodeling after valve repair for chronic severe mitral regurgitation: 1-year follow-up

Background: Chronic severe mitral regurgitation is associated with poor clinical outcome because chronic volume overload leads to hemodynamic changes and left ventricular and left atrial remodeling. Few data are available regarding left atrial volume index regression (LAVIR) and left ventricular mass index regression (LVMIR) after valve surgery for mitral regurgitation. We aimed to identify predictive correlates of LAVIR and LVMIR and to assess the relationship between these regressions. Hypothesis: Volume overload in chronic severe mitral regurgitation may influence left atrial and ventricular remodeling and reverse remodeling. Methods: Eighty-five patients who underwent valve repair for severe chronic mitral regurgitation were consecutively enrolled. Plasma N-terminal fragment of the prohormone brain natriuretic peptide (NT-proBNP) and echocardiographic measurements were performed before surgery, before discharge, and at 12 months after surgery. LAVIR and LVMIR were assessed using serial echocardiography. Results: There were significant decreases in left ventricular mass index (LVMI; from 125.9 ± 31.3 g/m² to 94.8 ± 28.6 g/m², P = 0.001) and left atrial volume index (LAVI; from 75.3 ± 33.5 mL/m² to 41.7 ± 16.0 mL/m², P = 0.001) after surgery. Preoperative LAVI positively correlated with preoperative LVMI (r = 0.437, P = 0.001) and LAVIR positively correlated with LVMIR (r = 0.347, P = 0.001). In multivariate stepwise linear regression analysis, preoperative LAVI, age, hypertension, and atrial fibrillation were independently predictive of LAVIR, and preoperative LVMI, hypertension, and NT-proBNP were independently predictive of LVMIR. Conclusions: Volume overload in chronic severe mitral regurgitation may influence left ventricular remodeling and reverse remodeling, as well as left atrial remodeling and reverse remodeling. Preoperative lower LAVI, younger age, absence of hypertension, and absence of atrial fibrillation may predict LAVIR, and preoperative lower LVMI, lower NT-proBNP levels, and absence of hypertension may predict LVMIR after surgery for chronic severe mitral regurgitation.