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 due to this population being excluded from landmark randomized controlled trials. This study aims to determine the rate of in-hospital DOAC use compared to warfarin early after cardiac surgery, evaluate factors associated with DOAC use, determine difference in post-operative length of stay, and characterize bleeding events. Methods A retrospective cohort study was conducted in adult patients with an indication 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 to warfarin. Results Of included 210 patients, 30% received a DOAC and 70% received warfarin on discharge. The most common DOAC used was apixaban (74.6%) and median post-operative day of initiation was 5 days. Patients receiving a DOAC were older (70.8 versus 68.0 years), had less valvular heart disease (38.1% versus 63.9%), more likely to be on a DOAC pre-operatively (50.8% versus 31.3%), and more likely to have undergone coronary artery bypass graft alone (54.0% versus 24.5%) compared to those on warfarin. Post-operative length of stay (7 versus 9 days, p=0.59) and in-hospital bleeding (1.6% versus 2.0%, p=1.00) did not differ between DOAC and warfarin groups. Conclusion At a quaternary referral center for cardiac surgery, DOACs were used in approximately one-third of patients with an indication for anticoagulation early after cardiac surgery.