Mitral valve repair rates correlate with surgeon and institutional experience

Mitral valve (MV) repair rates have lagged despite reported superior outcomes in patients with mitral regurgitation. The purpose of the present study was to evaluate the relationship between procedure volume and the propensity for MV repair in a multi-institution, regional patient cohort.

Society of Thoracic Surgeons-certified patient records of those undergoing MV repair or MV replacement (MVR) for moderate or severe mitral regurgitation were evaluated from 17 different centers (2001-2011). The relationship between the annual hospital and surgeon volume and the propensity for MV repair over MVR was analyzed using multivariable, mortality risk-adjusted models with restricted cubic splines.

A total of 4194 patients were evaluated (MV repair, 2516; MVR, 1662). The median annual mitral procedure volume was 54 operations for hospitals and 13 operations for surgeons. The overall MV repair rate was 60%, with significant variations among hospitals (range, 35%-70%) and surgeons (range, 0%-90%). The MVR patients presented with higher Society of Thoracic Surgeons Predicted Risk of Mortality scores (6% vs 2%, P < .001). After adjustment for Predicted Risk of Mortality score, both annual hospital (P = .04) and surgeon (P < .0001) procedure volume were associated with the probability of MV repair. The likelihood for MV repair correlated with an operative volume of ≥ 20 procedures annually. Among surgeons and hospitals performing ≥ 20 mitral operations annually, MV repair rates were greater (73% vs 26% and 62% vs 37%, respectively, P < .001 for both).

Significant variation in the performance of MV repair over MVR for mitral regurgitation persists in the modern surgical era. Average annual surgeon volume was more significantly associated with MV repair rate than institutional volume, with an increased likelihood for performance of MV repair among surgeons performing >20 procedures annually. In the upcoming era of percutaneous MV repair, surgeon volume and expertise as a gatekeeper should dictate access to this technology and the decisions for the best approach to MV repair.