Risk factors for sepsis and endocarditis and long-term survival following coronary artery bypass grafting

We sought to determine risk factors for sepsis and/or endocarditis (S/E) and to identify their impact on long-term survival after coronary artery bypass grafting (CABG). We studied 3760 consecutive patients who underwent isolated CABG from 1992 to 2002. Patients with CABG without S/E were compared with those who developed S/E. Long-term survival data (mean follow-up 5.2 years) were obtained from the National Death Index. Groups were compared by Cox proportional hazard models and Kaplan-Meier survival plots. The propensity for S/E was determined by logistic regression analysis and each patient with S/E was matched to one patient without S/E. Thirty-six patients (0.96%) developed S/E. Independent predictors for S/E were increased age (odds ratio [OR] 1.05 per year, 95% Confidence interval [95% CI] 1.00-1.09; p = 0.040) and the development of other major complications after CABG such as deep sternal wound infection (OR 30.80, 95% CI 9.50-99.82; p < 0.001), gastrointestinal complications (OR 19.48, 95% CI 7.14-53.18; p < 0.001), renal failure (OR 15.18, 95% CI 4.42-52.06; p < 0.001), intraoperative stroke (OR 13.11, 95% CI 4.81-35.69; p < 0.001) and respiratory failure (OR 12.95, 95% CI 5.69-29.45; p < 0.001). After adjustment for pre-, intra- and postoperative factors, the adjusted hazard ratio of long-term mortality for patients with S/E was 3.33 (95% CI 2.17-5.10; p < 0.001). There was no difference in 30-day mortality between matched groups (25.0% vs. 19.4% in patients without S/E, p = 0.778), however patients without S/E had better 5-year survival rate (52.7 +/- 8.7% vs. 16.2 +/- 6.2%; p = 0.0004). We have identified risk factors for S/E following CABG and we found that there was increased mortality in patients with S/E during a 10-year follow-up period.