Outcomes of surgical intervention for isolated active mitral valve endocarditis

Objective: Although several studies have examined the outcomes of mitral valve repair for infective endocarditis, no studies have documented the long-term outcomes of surgical intervention for active endocarditis confined to the mitral valve. Methods: One hundred four patients underwent surgical intervention for active infective endocarditis confined to the mitral valve over a 27-year period (mean age, 50 +/- 18 years; 52% female). The infected valve was native in 81 patients, previously repaired 6 patients, and prosthetic in 17 patients. Staphylococcus aureus was the most commonly isolated (32%) source of infection. Twenty-eight (27%) patients had annular abscesses. Surgical intervention consisted of valve repair or replacement for limited infection and radical resection, annular patch reconstruction, and valve replacement for annular abscess. Mean follow-up was 5.6 +/- 4.4 years (range, 0-20 years) and was complete. Results: There were 9 (8.7%) in-hospital deaths and 28 (27%) late deaths. Overall survival at 5, 7, and 10 years was 73% +/- 5%, 68% +/- 5%, and 58% +/- 6%, respectively. At 7 years, freedom from recurrent endocarditis was 89% +/- 4% and freedom from reoperation was 94% +/- 3%. Event-free survival at 7 and 10 years was 60% +/- 6% and 46% +/- 7%, respectively, and was significantly higher in patients with native endocarditis versus those with nonnative endocarditis (ie, prosthetic or previously repaired; 7 years: 63% +/- 7% vs 50% +/- 12%, P<.005). Preoperative shock, S aureus infection, and bioprosthesis insertion were independent predictors of death from all causes. The patients in the bioprosthesis group were older (57 +/- 20 years vs 44 +/- 15 years in the mechanical group and 46 +/- 12 years in the repair group, P = .003). Conclusions: Surgical intervention for isolated active mitral valve endocarditis remains difficult, with high morbidity and mortality in the long term. Event-free survival is worse in those who have nonnative mitral valve endocarditis.