Direct Oral Anticoagulant Use Early After Cardiac Surgery: A Retrospective Cohort Study

Background: There is limited literature guiding the prescribing of direct oral anticoagulants (DOACs) early after cardiac surgery as this population has been excluded from landmark randomized controlled trials. This study aims to determine the rate of in -hospital DOAC use compared with warfarin early after cardiac surgery, evaluate factors associated with DOAC use, determine difference in postoperative length of stay, and characterize bleeding events. Methods: A retrospective cohort study was conducted in adult patients with indications for anticoagulation and receiving either a DOAC or warfarin after cardiac surgery during their index hospitalization. Patients were excluded if they had any contraindications to DOAC use. The primary outcome was the proportion of patients discharged on a DOAC compared with warfarin. Results: Of included 210 patients, 30% received DOACs and 70% received warfarin on discharge. The most common DOAC used was apixaban (74.6%), and median postoperative day of initiation was 5 days. Patients receiving DOACs were older (70.8 vs 68.0 years), had less valvular heart disease (38.1% vs 63.9%), were more likely to be on DOACs preoperatively (50.8% vs 31.3%), and were more likely to have undergone coronary artery bypass graft alone (54.0% vs 24.5%) compared with those on warfarin. Postoperative length of stay (7 vs 9 days; P = 0.59) and in-hospital bleeding (1.6% vs 2.0%; P = 1.00) did not differ between DOAC and warfarin groups. Conclusions: At a quaternary referral centre for cardiac surgery, DOACs were used in approximately one-third of patients with an indication for anticoagulation early after cardiac surgery.