Infective endocarditis in a university hospital without on-site cardiac surgery: temporal trends over 37 years

The clinical spectrum and management of infective endocarditis (IE) in non-referral centers are poorly characterized. We aimed to analyze long-term trends in IE in a university hospital without on-site cardiac surgery.

Retrospective analysis of prospectively collected population-based data from IE patients across four time periods (1988-2024) at Hospital Universitario Lucus Augusti.

698 episodes were included (86.5% definite IE). 75.4% occurred in men. Median age was 72.5 years (IQR 63-80) and increased significantly over time (63 to 77 years; p < 0.001). Incidence rose from 3.5 to 16.9 cases per 100 000 inhabitants (overall 9.2/100 000). Age-adjusted Charlson Comorbidity Index (CCI) increased from 3 (IQR 1-4) to 6 (IQR 4-7) (p < 0.001). Degenerative valvular disease-related IE and prosthetic valve IE increased significantly. The Streptococcus bovis group was the most frequent etiology (23.1%), with a rise in Enterococcus spp. and coagulase-negative staphylococci (p < 0.001). Non-paravalvular complications occurred in 76.2%, with increasing rates of heart failure. Transfer to a referral center remained stable (20.5%) and was more frequent in younger, less comorbid patients. Cardiac surgery was indicated in 31% and performed in 15.6%; overall in-hospital mortality was 19.9%, unchanged over time.

The incidence of IE increased markedly in parallel with aging, rising comorbidity, and degenerative and prosthetic valve disease. Despite these changes, surgical rates and mortality remained stable, suggesting that referral patterns and local population characteristics should be considered when interpreting the clinical spectrum and outcomes of IE.