Survival and outcomes following bioprosthetic vs mechanical mitral valve replacement in patients aged 50 to 69 years

Abstract

Importance: In nonelderly patients with mitral disease requiring valve replacement, deciding between bioprosthetic and mechanical prosthetic valves is challenging because long-term survival and morbidity are not well defined.

Objective: To quantify survival and major morbidity after mitral valve replacement in patients aged 50 to 69 years.

Design, setting, and participants: Retrospective cohort analysis of 3433 patients (aged 50-69 years) who underwent primary, isolated mitral valve replacement in New York State hospitals from 1997-2007. Follow-up ended November 30, 2013; median duration was 8.2 years (range, 0-16.8 years). Propensity score matching for 19 baseline characteristics yielded 664 patient pairs.

Exposures: Bioprosthetic vs mechanical prosthetic mitral valve replacement.

Main outcomes and measures: All-cause mortality, stroke, reoperation, and major bleeding events.

Results: No survival difference was observed between use of mechanical prosthetic and bioprosthetic mitral valves in patients aged 50 to 69 years matched by propensity score or in a subgroup analysis of age by decade. Among patients matched by propensity score, the incidences of stroke and bleeding events were both significantly higher in those who received mechanical prosthetic mitral valves compared with those who received bioprosthetic mitral valves; however, the incidence of reoperation was lower in the mechanical prosthesis group compared with the bioprosthesis group. [table: see text]

Conclusions and relevance: Among patients aged 50 to 69 years undergoing mitral valve replacement in New York State, there was no significant survival difference at 15 years in patients matched by propensity score who underwent mechanical prosthetic vs bioprosthetic mitral valve replacement. Mechanical prosthetic valves were associated with lower risk of reoperation but greater risk of bleeding and stroke. Even though these findings suggest bioprosthetic mitral valve replacement may be a reasonable alternative to mechanical prosthetic valve replacement in patients aged 50 to 69 years, the 15-year follow-up was insufficient to fully assess lifetime risks, particularly of reoperation.