Durable Robotic Mitral Repair of Degenerative Primary Regurgitation With Long-Term Follow-Up.

BACKGROUND: Variation in degenerative mitral morphology may contribute to suboptimal repair rates. This study evaluates outcomes of a standardized mitral repair technique. METHODS: An institutional clinical registry was used to identify 1036 consecutive patients undergoing robotic mitral surgery between 2005 and 2020: 87% (n = 902) had degenerative disease. Calcification, failed transcatheter repair, and endocarditis were excluded, leaving 582 (68%) patients with isolated posterior leaflet and 268 (32%) with anterior or bileaflet prolapse. Standardized repair comprised triangular resection and true-sized flexible band in posterior leaflet prolapse. Freedom from greater than 2+ moderate mitral regurgitation stratified by prolapse location was assessed using competing risk analysis with death as a competing event. Median follow-up was 5.5 (range 0-15) years. RESULTS: Of patients with isolated posterior leaflet prolapse, 87% (n = 506) had standardized repairs and 13% (n = 76) had additional or nonresectional techniques vs 24% (n = 65) and 76% (n = 203), respectively, for anterior or bileaflet prolapse (P < .001). Adjunctive techniques in the isolated posterior leaflet group included chordal reconstruction (8.6%, n = 50) and commissural sutures (3.4%, n = 20). Overall, median clamp time was 80 (interquartile range, 68-98) minutes, 17 patients required intraoperative re-repair, and 6 required mitral replacement. Freedom from greater than 2+ regurgitation or reintervention at 10 years was 92% for posterior prolapse (vs 83% for anterior or bileaflet prolapse). Anterior or bileaflet prolapse was associated with late greater than 2+ regurgitation (hazard ratio, 3.0; 95% confidence interval, 1.3-7.0). CONCLUSIONS: Posterior leaflet prolapse may be repaired in greater than 99% of patients using triangular resection and band annuloplasty, with satisfactory long-term durability. Increased risk of complex repairs and inferior durability highlights the value of identifying anterior and bileaflet prolapse preoperatively.