Clinical Presentation of Native Mitral Valve Infective Endocarditis Determines Long-Term Outcome after Surgery

BACKGROUND AND AIM: Surgery is performed in up to half of all cases of active infective endocarditis (IE) but the associated mortality remains high. The aim was to examine the effect of the preoperative clinical presentation on long-term survival of patients undergoing surgery for isolated native mitral valve infective endocarditis. METHODS: A retrospective study was conducted on 100 patients who had undergone mitral valve surgery from 1998 to 2014 for ongoing isolated, native valve IE. Patients were stratified depending on preoperative symptoms: clinical stroke due to septic cerebral embolism, congestive heart failure, and uncontrolled bacteremia. Group A had none of the clinical symptoms, Group B had one of the above clinical symptoms, and Group C had ≥2 symptoms. Follow-up was 100% complete for survival (median 3.8 years, IQR 0.8-7.7). Event rates were estimated with the Kaplan-Meier method and Cox-regression was performed. RESULTS: Overall 30-day mortality was 5% (n = 5); 0% in Group A; 8% in Group B (n = 4); and 8% in Group C (n = 1), p = 0.24. Five-year survival was 87.0 ± 6.1% in Group A, 62.6 ± 7.1% in Group B, and 33.8 ± 15.2% in Group C. Grouping by clinical presentation was found to be an independent predictor of mortality (Group B, HR 2.37, 95% CI 1.02-5.50; Group C, HR 4.07, 95% CI 1.56-10.6). CONCLUSIONS: Long-term survival after surgery for native mitral valve IE was independently influenced by the presence of preoperative embolic stroke, congestive heart failure or uncontrolled bacteremia alone, or in combination.