Mitral valve surgery for atrial functional mitral regurgitation: predicting recurrent mitral regurgitation and mid-term outcome

OBJECTIVES: This study aimed to elucidate the mid-term outcomes and risk factors for recurrent mitral regurgitation after mitral valve (MV) surgery for atrial functional mitral regurgitation (AFMR). METHODS AND RESULTS: We retrospectively analyzed data of 50 consecutive patients (median age 74 years; 29 men) who underwent mitral valve surgery for AFMR between January 2001 and January 2019. Mean atrial fibrillation duration was 12 years. During the follow-up period of 4.6 ± 4.4 years, 5 cardiac-related deaths were identified. Five- and 10-year freedom from cardiac-related death rate for all patients was 88.4% and 78.6%. In total, 42 patients underwent MV repair with mitral annuloplasty and 8 underwent MV replacement. Five- and 10-year freedom from cardiac-related death rate in patients who underwent MV repair was 93.1% and 82.7%, which was better than MV replacement (log rank p = 0.04). During the follow-up period, MR recurrence rate was 16.8% at 5 and 10 years for the patients who underwent MV repair. Univariate analysis showed that partial band annuloplasty and preoperative elevated left ventricular end-systolic volume index were risk factors for recurrent MR after MV repair. Multivariate analysis identified partial band annuloplasty as the independent predictor for recurrent MR during long-term follow-up after MV repair for AFMR. CONCLUSION: Patients who underwent MV repair for AFMR could have an acceptable mid-term outcome. However, MVR might not improve the mid-term outcome in patients with AFMR. The use of partial bands for mitral annuloplasty would not be recommended in terms of recurrent MR mid-term. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11748-022-01793-8.