Aims: Patients with left-sided heart valve replacement are considered at high-risk of infective endocarditis (IE). However, data on the incidence and risk factors associated with IE are sparse.

Methods and results: Through Danish administrative registries, we identified patients who underwent left-sided heart valve replacement from January 1996 to December 2015. Patients were categorized in mitral and aortic valve replacement (MVR and AVR) and followed until: 12 years after valve surgery, end of study, death, emigration, or hospitalization due to IE, whichever came first. Multivariable adjusted Cox proportional hazard analysis was used to investigate which baseline characteristics were associated with IE. A total of 18 041 patients were included. The cumulative IE risk at 10 years follow-up was 5.2% in both MVR and AVR patients. In patients with MVR, male sex [hazard ratio (HR) = 1.68, 95% confidence interval (95% CI) 1.06-2.68], bioprosthetic valve (HR = 1.91, 95% CI 1.08-3.37), and heart failure (HR = 1.69, 95% CI 1.06-2.68) were among factors associated with an increased risk of IE. In AVR patients, male sex (HR = 1.59, 95% CI 1.33-1.89), bioprosthetic valve (HR = 1.70, 95% CI 1.35-2.15), and cardiac implantable electronic device (CIED) (HR = 1.57, 95% CI 1.19-2.06) were among factors associated with an increased risk of IE.

Conclusion: Infective endocarditis after left-sided heart valve replacement is not uncommon and occurs in about 1/20 over 10 years. Male, bioprosthetic valve, and heart failure were among factors associated with IE in MVR patients while male, bioprosthetic valve, and CIED were among factors associated with IE in AVR patients.