Infective endocarditis after surgical aortic or mitral valve replacement: A nationwide population-based study

Objective: Evidence regarding the incidence of prosthetic valve endocarditis and its association with the use of mechanical or biologic prosthetic valves is limited. Methods: Patients who underwent aortic or mitral valve replacement in the years 2000 to 2017 were identified from Taiwan's National Health Insurance Research Database and grouped according to the type of prosthesis used (mechanical or biologic). Propensity score matching was performed to reduce confounding. Results: A total of 22,844 patients were included, with 11,950 (52.2%) and 10,934 (47.8%) in the mechanical prosthesis and biologic prosthesis groups, respectively. After matching, each group contained 5441 patients. During follow-up, patients with a biologic prosthesis had a significantly higher risk of infective endocarditis (IE) than those with a mechanical valve (3.4% vs 1.9%; subdistribution hazard ratio, 1.78; 95% CI, 1.40-2.26). Moreover, biologic prostheses were associated with greater risks of all-cause mortality and redo valve surgery, but lesser risks of ischemic stroke, hemorrhagic stroke, major bleeding, and gastrointestinal bleeding. In subgroup analysis, biologic prostheses were consistently associated with a greater risk of IE in all subgroups, specifically single-valve replacement–aortic, single-valve replacement–mitral, double-valve replacement, active IE (IE diagnosed during index hospitalization), any IE (active or old), and not having a history of IE. Conclusions: In this nationwide population-based retrospective cohort study, biologic prosthesis use was associated with a greater risk of IE during follow-up compared with mechanical valve use. However, mechanical valve use was associated with a greater risk of ischemic stroke and hemorrhagic complications.