Abstract P131: Postoperative Atrial Fibrillation is Not Associated With Hospital Mortality or Early 30-day Mortality After Coronary Artery Bypass Graft Surgery
Background: Postoperative atrial fibrillation (AF) is the most common arrhythmia after coronary artery bypass surgery (CABG) and is associated with an increased morbidity. Recently, it has been suggested that postoperative AF is also associated with increased postoperative mortality.
Aim: to investigate whether postoperative AF after isolated CABG was associated with a higher hospital mortality and 30-day mortality.
Methods: We reviewed data from our prospective cardiac surgery database of all patients (n=2791) undergoing isolated CABG from January 2003 through December 2006 at a large university medical center. The Mann-Whitney test was used to test for differences in continuous variables between the AF and non-AF groups, while the Chi-square test was used for categorical variables. Stepwise logistic regression analysis was used to identify independent predictors of hospital mortality, and 30-day mortality.
Results: The mean age was 68±9.1yrs, and mean EuroSCORE was 6.91±3.18. The overall incidence of postoperative AF was 32.3%. The AF group was older (70.5±7.8 vs 66.8±9.5, p<0.0001). There was a significant difference in the EuroSCORE, (AF: 7.6±3.2 vs non-AF: 6.6±3.1, p<0.0001), indicating that the AF group was at greater risk for postoperative mortality. Although there was a significant association between EuroSCORE and postoperative AF (p<0.0001), there was no significant difference in hospital and 30-day mortality between the AF and non-AF groups. The overall hospital mortality was 1.9%, with no difference between the two groups (AF1.88% vs non-AF1.9%, p=0.91). The thirty-day mortality was 1.2%, again with no significant difference between the groups (AF1.33% vs non-AF1.13%, p=0.89). Furthermore, postoperative AF was not predictive of either hospital mortality or 30-day mortality after CABG on either univariate or multivariate analysis.
Conclusion: Postoperative AF is associated with a higher EuroSCORE, but is neither associated with, nor predictive of, hospital mortality or 30-day mortality after CABG.