Association of atrial fibrillation and oral anticoagulant use with perioperative outcomes after major noncardiac surgery

Background — We examined the association of atrial fibrillation (AF) and oral anticoagulant use with perioperative death and bleeding among patients undergoing major noncardiac surgery.

Methods and Results — A population‐based study of patients aged 66 years and older who underwent elective (n=87 257) or urgent (n=35 930) noncardiac surgery in Ontario, Canada (April 2012 to March 2015) was performed. Outcomes were compared between AF groups using inverse probability of treatment weighting using the propensity score. Of 4612 urgent surgical patients with AF, treatments before surgery included warfarin (n=1619), a direct oral anticoagulant (DOAC) (n=729), and no anticoagulation (n=2264). After urgent surgery, the death rate within 30 days was significantly higher in patients with AF compared with patients with no AF (hazard ratio [HR], 1.28; 95% confidence interval [CI], 1.12–1.45). In contrast, among 4769 elective surgical patients with AF treated with warfarin (n=1453), a DOAC (n=1165), or no anticoagulation (n=2151), prior AF was not associated with higher mortality. Comparing patients with AF who were or were not anticoagulated, there was no difference in 30‐day mortality after urgent (HR, 0.95; 95% CI, 0.79–1.14) or elective (HR, 0.65; 95% CI, 0.38–1.09) surgery. There was no difference in 30‐day mortality between patients with AF treated with a DOAC or warfarin after urgent (HR, 0.91; 95% CI, 0.70–1.18) or elective (HR, 1.64; 95% CI, 0.77–3.53) surgery. Bleeding and thromboembolic rates did not differ significantly among patients with AF prescribed a DOAC or warfarin.

Conclusions — Prior AF was associated with 30‐day mortality among patients undergoing urgent surgery. In patients with AF, neither the preoperative use of oral anticoagulants, nor the type of agent (either a DOAC or warfarin) were associated with the rate of 30‐day mortality.