Incidence and factors associated with mitral valve reoperation in patients undergoing surgery for mitral regurgitation: A nationwide cohort study.

BACKGROUND

When patients undergo surgery for mitral regurgitation, risk of reoperation is of concern.

AIMS

To examine the incidence and factors associated with mitral reoperation following surgery for mitral regurgitation according to type of surgery.

METHODS

Patients undergoing first-time surgery for mitral regurgitation, 1996-2021, were identified from nationwide registries. According to index surgery, the population was categorized into 1) mitral repair; 2) mechanical prostheses; 3) bioprostheses. Patients were followed from discharge with a maximum of 15 years of follow-up and cumulative incidence of reoperation was examined. Multivariable Cox analysis was used to examine factors associated with reoperation.

RESULTS

We identified 6958 patients: 4624 with mitral repair (72 % male, median age 66), 1250 with mechanical prosthesis (52 % male, median age 59), and 1084 with bioprosthesis (57 % male, median age 74). Cumulative incidence of reoperation was 7.3 % for repair (median 7.2 years follow-up), 6.1 % for mechanical prostheses (median 10.9 years follow-up), and 7.1 % for bioprostheses (median 4.5 years follow-up). Within first year, 22.6 % of reoperations were preceded by infective endocarditis. In long-term follow-up, bioprosthetic replacement was associated with a higher reoperation rate, while increasing age, male sex and mechanical prosthesis were associated with lower reoperation rate.

CONCLUSIONS

In patients operated for mitral regurgitation, reoperation was infrequent at approximately 7 % for all intervention types during a maximum of 15-year follow-up. In adjusted analysis, bioprosthetic replacement was associated with a higher rate of reoperation, while increasing age, male sex and mechanical prosthesis was associated with a lower rate of reoperation.