Native infective endocarditis: Which determinants of outcome remain after surgical treatment?

Summary Surgical therapy of native infective endocarditis is still considered as a particular challenge, due to remaining morbidity and mortality up to 20%. Further risk analysis and characterization of clinical features is of great importance for further improvement of surgical results. The aim of this retrospective study was a risk analysis concerning clinical features of the pre–, intra– and postoperative period. Between 02/1997 and 12/2003, 165 patients (130 male, 35 female, age 55.5 ± 13.8 years) were referred for surgical therapy of infective endocarditis at our institution. Preoperative, intraoperative and postoperative features were evaluated for their influence on the early postoperative course and the mid–term follow–up. In the majority of patients (pts) the aortic valve was infected (n = 83, 50.3% of pts), followed by mitral valve (n = 33; 20.0%), tricuspid valve (n = 10, 6.0%) and pulmonary valve (n = 2; 1.2%). Double valve affection was recorded in 37 pts (22.4%). Streptococci (n = 66, 40.0%) and staphylococci (n = 66, 40.0%) were the most common pathogens. The overall hospital mortality rate was 10.9% (n = 18), during follow–up (mean follow–up 3.3 ± 2.5 years) a further 20 pts (12.1%) died. Main predictors for hospital mortality in multivariate analysis were older age (p = 0.01), prolonged ICU stay, prolonged intubation (p = 0.03; p = 0.02) and the continuous postoperative need of alpha–catecholamine medication (p < 0.01). Significant predictors of overall mortality were older age (> 70 years) and diabetes (p = 0.03; p = 0.03). Reinfection occurred in 6.1% of patients (n = 10). Actuarial freedom from recurrent infection was 97% at 1 year and 93.9% at 5 years. Surgical therapy of infective endocarditis is associated with good clinical results in the early and mid–term follow–up. Predictors of outcome particular include preoperative risk constellation or comorbidity (age, diabetes) and variables of the immediate postoperative course.