Early recurrence in patients with post-CABG atrial fibrillation not a risk factor for mortality

In patients with new-onset postoperative atrial fibrillation (POAF) following coronary artery bypass grafting (CABG), early AF recurrence is common but not associated with death, according to a study.

For the study, researchers used prospectively collected data from the SWEDEHEART (Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies) registry and three other mandatory national registries.

A total of 35,329 patients were identified, among whom 10,609 (30.0 percent) had POAF following CABG and were included in the analysis. The median age of the study population was 71 years, and most patients were men (81.6 percent).

Over a median follow-up of 7.1 years, early AF recurrence (defined as an episode of AF leading to hospital care within 3 months after discharge) occurred in 6.7 percent of patients.

The primary outcome of all-cause mortality was more common among patients with versus without early AF recurrence (2.21 vs 2.03 per 100 patient-years). The same was true for the secondary outcomes of heart failure hospitalization (3.94 vs 2.79 per 100 patient-years) and major bleeding within 2 years of discharge (3.97 vs 2.74 per 100 patient-years).

However, multivariable Cox regression models showed no significant association between early AF recurrence and all-cause mortality (adjusted hazard ratio [AHR], 1.17, 95 percent confidence interval [CI], 0.80–1.74; p=0.41). Exploratory analyses, on the other hand, indicated that early AF recurrence contributed to an 80-percent increase in the risk of heart failure hospitalization (AHR, 1.80, 95 percent CI, 1.32–2.45; p=0.001) and a 92-percent increase in the risk of major bleeding within 2 years of discharge (AHR, 1.92, 95 percent CI, 1.42–2.61; p<0.001).