Long-term outcomes of mitral valve replacement in patients with systemic autoimmune disease: a nationwide retrospective cohort study

Late outcomes among patients with systemic autoimmune disease (SAD) who underwent heart valve replacement are not well established. This study aimed to compare the long-term outcomes after an initial, isolated mitral valve replacement (MVR) with either a bioprosthesis or a mechanical prosthesis in patients with SAD.

In this nationwide retrospective cohort study, we retrieved longitudinal data from the National Health Insurance Research Database for patients with SAD undergoing primary MVR from 1 January 2001, to 31 December 2018.

A total of 34,563 patients undergoing heart valve replacement for the first time between January 2001 and December 2018 were identified. After applying exclusion criteria and propensity-score matching, we included 273 bioprosthesis recipients and 273 mechanical prosthesis recipients, and the median duration of follow-up was 5.98 years and 7.44 years, respectively. There was no significant difference between the bioprosthesis group and the mechanical prosthesis group in the incidences of all-cause mortality (hazard ratio [HR]: 1.26, 95% confidence interval [CI]: 0.97 to 1.64) and the composite outcome of major adverse prosthesis-related events (MAPE) (HR: 0.91, 95% CI: 0.75 to 1.10). The risk of ischemic stroke was lower in the bioprosthesis group (HR: 0.60, 95% CI: 0.42 to 0.87). Subgroup analyses showed that bioprostheses were associated with a lower risk of MAPEs (10-year restricted mean survival time [RMST] difference: 1.25 years, 95% CI: 0.28 to 2.21) and major bleeding (10-year RMST difference: 1.11 years, 95% CI: 0.03 to 2.19) in male patients.

Among patients with SAD undergoing MVR, there was no significant difference between bioprostheses and mechanical prostheses in all-cause mortality and the composite outcome of MAPEs. However, bioprostheses showed a lower risk of ischemic stroke. In male patients, bioprostheses were linked to fewer MAPEs and major bleeding.