Echocardiographic Indices for Optimal Timing of Mitral Valve Repair in Degenerative Mitral Regurgitation in Japanese Patients

Abstract

Background: Left ventricular (LV) dysfunction after mitral valve (MV) repair for degenerative mitral regurgitation (DMR) is a poor prognostic factor. Preoperative LV end-systolic diameter (LVESD) and LV ejection fraction (LVEF) are used in guidelines as indices for LV dysfunction, with cut-off values of 60% for LVEF and 40 mm for LVESD. However, these factors have received little validation in Japanese patients.

Methods and Results: We evaluated preoperative echocardiographic data in 322 Japanese patients who underwent MV repair for DMR to identify factors associated with postoperative LV dysfunction. Postoperative LV dysfunction was observed in 31 (10%) patients, who had greater LVESD (39±6 mm vs. 33±5 mm; P<0.001) and lower LVEF (62±5% vs. 67±5%; P<0.001) preoperatively, compared with the non-LV dysfunction group. The optimal threshold of preoperative LVESD and LVEF for predicting postoperative LV dysfunction in receiver operating characteristic curve analysis was 36 mm (AUC=0.819; P<0.001) and 61% (AUC=0.706; P<0.001), respectively. Kaplan–Meier analysis showed a significantly lower rate of avoided adverse cardiac events in the LV dysfunction group (P<0.001).

Conclusions: The criteria for LVESD in MV repair in patients with DMR should be lower than the values indicated by the guidelines. Adoption of these revised criteria may improve prognosis after surgery in Japanese patients.