Mitral Surgery after Transcatheter Edge-to-Edge Repair: Society of Thoracic Surgeons Database Analysis.

Background Transcatheter edge-to-edge (TEER) mitral repair may be complicated by residual or recurrent mitral regurgitation. Increasing need for surgical reintervention has been reported but operative outcomes are ill-defined. Objectives This study evaluated national outcomes of mitral surgery after TEER. Methods The Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database was used to identify 524 adults who underwent mitral surgery after TEER between July 2014 and June 2020. Emergencies (5.0%, n=26), previous mitral surgery (5.3%, n=28) or open implantation of transcatheter prostheses (1.5%, n=8) were excluded. The primary outcome was 30-day or in-hospital mortality. Results In the study cohort of 463 patients median age was 76 years (interquartile range (IQR) 67-81 years), median left ventricular ejection fraction 57% (IQR 48-62%), and 177 (38.2%) patients had degenerative disease. Major concomitant cardiac surgery was performed in 137 (29.4%) patients: in patients undergoing isolated mitral surgery median STS predicted mortality was 6.5% (IQR 3.9-10.5%), observed mortality was 10.2% (n=23/225) and the ratio of observed to expected mortality was 1.2 (95% CI 0.8-1.9). Predictors of mortality included urgent surgery (odds ratio (OR) 2.4, 95% confidence interval (CI) 1.3-4.6), non-degenerative / unknown etiology (OR 2.2, 95% CI 1.1-4.5), creatinine >2.0mg/dl (OR 3.8, 95% CI 1.9-7.9) and age >80 (OR 2.1, 95% CI 1.1-4.4). In a volume outcomes analysis in an expanded cohort of 591 patients at 227 hospitals, operative mortality was 2.6% (n=2/76) in 4 centers that performed >10 cases versus 12.4% (n= 64/515) in centers performing fewer (p=0.01). The surgical repair rate after failed TEER was 4.8% (n=22), and 6.8% (n=12) in degenerative disease. Conclusion This study indicates mitral repair is infrequently achieved after failed TEER, which may have implications for treatment choice in lower-risk and younger patients with degenerative disease. These findings should inform patient consent for TEER, clinical trial design and clinical performance measures.