Clinical and Prognostic Impact of a New Left Ventricular Ejection Index in Primary Mitral Regurgitation Because of Mitral Valve Prolapse

<jats:sec> <jats:title>Background—</jats:title> <jats:p>To prevent left ventricular dysfunction (LVD), surgery is recommended in patients with severe primary mitral regurgitation as soon as ejection fraction (EF) ≤60% or LV end-systolic diameter ≥40 mm. However, LVD may be concealed behind preoperative normal LVEF and LV end-systolic diameter. We sought to identify whether a new composite echocardiographic Doppler marker of the LV ejection according to the LV dilatation may predict postoperative LVD and outcome after mitral valve repair in patients with primary mitral regurgitation.</jats:p> </jats:sec> <jats:sec> <jats:title>Methods and Results—</jats:title> <jats:p> Between 1991 and 2010, patients who underwent mitral valve repair for primary mitral regurgitation were studied. From preoperative echocardiography, we calculated LV ejection index (LVEI) using following formula: LVEI=indexed LV end-systolic diameter/LV outflow tract time–velocity integral. In the 278 patients included, the best correlation with postoperative LVEF was found with LVEI ( <jats:italic>r</jats:italic> =−0.40; <jats:italic>P</jats:italic> <0.0001), even in patients with preoperative LVEF≥60% ( <jats:italic>r</jats:italic> =−0.46; <jats:italic>P</jats:italic> <0.0001). In multivariable analysis, LCEI>1.13 was an independent predictor of postoperative LVD ( <jats:italic>P</jats:italic> <0.0001). During a mean follow-up of 10±4.6 years, 67 (29%) deaths occurred. When compared with patients with preserved LVEI, those with LVEI>1.13 had significantly lower both survival and cardiac death–free survival ( <jats:italic>P</jats:italic> =0.017 and <jats:italic>P</jats:italic> =0.008, respectively). Similar results were found in patients with preoperative LVEF≥60% ( <jats:italic>P</jats:italic> =0.049 and <jats:italic>P</jats:italic> =0.016, respectively). In Cox proportional hazard model, after meticulous adjustment for cofactors, LVEI>1.13 remains independently associated with death (hazard ratio, 1.64; <jats:italic>P</jats:italic> =0.039) and cardiac-related death (hazard ratio, 3.27; <jats:italic>P</jats:italic> =0.026). </jats:p> </jats:sec> <jats:sec> <jats:title>Conclusions—</jats:title> <jats:p>After mitral valve repair for primary mitral regurgitation, the preoperative LVEI is a new and simple composite parameter of both LV dilatation and LV forward flow able to accurately predict postoperative LVD and outcome.</jats:p> </jats:sec>