Determinants of Early Mortality and Late Survival in Mitral Valve Endocarditis

Abstract

Background Infective mitral valve endocarditis continues to be a significant surgical challenge. The objective of this study was to examine our experience with mitral valve endocarditis surgery and identify determinants of early mortality and late survival. Methods and Results Over a 24-year period, mitral valve surgery was performed in 96 patients for infective mitral valve endocarditis. Patient age ranged from 20 to 78 years (median age, 52 years). There were 44 women (46%), and 48 of the 96 patients (50%) were in New York Heart Association functional class IV before surgery. Native valve endocarditis (NVE) and prosthetic valve endocarditis (PVE) were present in 72 patients (75%) and 24 patients (25%), respectively. Surgery during the active phase of endocarditis (AE) was required in 60 patients (62%) and during the healed phase (HE) in 36 (38%). The main indications for surgery in the AE group were congestive heart failure (60%), active sepsis (67%), peripheral emboli (47%), and acute renal failure (20%), and for the HE group the main indication was progressive congestive heart failure (69%). The overall operative mortality was 5.2%. Multivariate logistic regression analysis identified PVE (odds ratio [OR] 22.5; ±95% confidence interval, CI, 1.9 to 268; P =.014) and an associated procedure (OR 13.3; ±95% CI, 1.5 to 120; P =.021) to be independent predictors for early mortality. Follow-up was 97% complete, with a median of 3.5 years. Overall 5- and 10-year survivals were 83±4% and 63±8%, respectively. Multivariate analysis for late mortality identified PVE to be a significant predictor of late mortality (hazards ratio=3.1, ±95% CI, 1.4 to 6.8, P =.006). There were no significant differences in long-term morbidity results among the various subsets of mitral valve endocarditis. Conclusions Mitral valve surgery for infective endocarditis is a significant high-risk procedure for PVE and when combined with associated procedures. The activity of endocarditis does not appear to have any influence on early mortality or long-term survival.