Real-world anticoagulant use and clinical outcomes in postoperative atrial fibrillation after coronary artery bypass grafting: a nationwide practice-based cohort from The Netherlands Heart Registration

AIMS: Postoperative atrial fibrillation (POAF) occurs in 15-40% of patients following coronary artery bypass grafting (CABG). Existing risk scores are unsuited to its transient nature, and evidence for long-term oral anticoagulation (OAC) remains limited. Although guidelines suggest balancing thromboembolic and bleeding risk, unclear recommendations and limited real-world data drive practice variation. This study evaluated OAC use and outcomes in a national POAF cohort after CABG.

METHODS AND RESULTS: This retrospective study included adults undergoing isolated CABG (2013-2022) from the Netherlands Heart Registration, linked to mortality and pharmacological data from Statistics Netherlands. Patients with prior atrial fibrillation or preoperative OAC were excluded. Outcomes included short-term complications and long-term cause-specific mortality, comparing OAC with antiplatelets. Among 44 601 CABG patients, 11 054 (24.8%) developed POAF. Of these, 10 750 were successfully linked. Mean age was 68.9 years; 81.7% were male. OAC therapy was initiated in 43.6% of patients, rising from 38.7% (2013) to 53.7% (2022). Within 30 days, mortality was 1.6%, cerebrovascular events 1.3%, and bleeding reintervention 5.4%. Most discontinued OAC after 1 year, while 10.3% continued for 10 years. Crude thromboembolic mortality was lower among OAC users (0.04 vs. 0.42 per 100 patient-years), while bleeding-related mortality remained low (0.00 vs. 0.08). However, survival analyses from 30 days postoperatively showed no significant differences between groups.

CONCLUSION: Among POAF patients after CABG, crude mortality was lower in OAC users, but no survival benefit was observed from 30 days onward. Low long-term OAC continuation without excess thromboembolic mortality suggests the potential value of time-limited anticoagulation strategies.