Population-Based Analysis of Late Outcomes of Mitral Valve Repair for Degenerative Mitral Valve Regurgitation

Background: Population-based analyses may reduce uncertainty related to referral bias and/or incomplete follow-up.

Objectives: This study analyzed long-term mortality and durability of mitral valve repair in a geographically defined population with clinical and echocardiographic follow-up.

Methods: We used the Rochester Epidemiology Project to identify 153 Olmsted County patients who underwent mitral valve repair for degenerative regurgitation from 1993 to 2018. Survival was compared to a gender- and age-matched U.S. population using the Kaplan-Meier method. Cumulative incidence and repeat operation rates were estimated, accounting for the completing risk of death.

Results: The median age of the cohort was 61 years (IQR: 53-73 years), 112 patients (73%) were men, and the left ventricular ejection fraction was 65% (IQR: 60%-69%). Triangular resection of the P2 scallop combined with a 63 mm posterior band annuloplasty was performed in 108 (71%) patients. The median clinical follow-up was 13.8 years (IQR: 11.5-16.2 years), while echocardiography follow-up was available in 152 (99%) patients at 6.6 years (IQR: 1.3-12.8 years). The probability of developing severe mitral regurgitation was 4% (IQR: 3%-7%) in 9 years. Cumulative incidence of repeat mitral valve operation was 8% (n = 10) at 20 years. The probability of developing severe tricuspid regurgitation was 5% (IQR: 4%-8%) in 10 years, but no subsequent tricuspid valve operation was performed. Survival following mitral valve repair was superior to an age- and sex-matched control population (P < 0.001).

Conclusions: Mitral valve repair for degenerative disease is durable with exceedingly low repeat operation and mortality up to 20 years of follow-up. There was also a low rate of subsequent development of significant tricuspid valve regurgitation.