Anticoagulation in patients with atrial fibrillation undergoing inpatient total knee arthroplasty: A matched analysis

Background: Patients with atrial fibrillation (AF) often require lifetime anticoagulation using drugs such as Warfarin and Direct-acting Oral Anticoagulants (DOAC). It is important to assess the impact that prior anticoagulant use has on the post-operative complications in patients with AF undergoing TKA. Methods: This is a retrospective analysis of the PearlDiver database querying all patients who underwent an inpatient TKA. Patients who had AF and filled a prescription for at least 30 days of either Warfarin or a DOAC were matched to control cohorts. Medical and surgical complications 30 and 90 days post-operatively were compared between the two groups. Results: 4396 patients made up the group with AF on warfarin, while 5383 patients made up the cohort with AF on DOAC and their corresponding controls. Patients on anticoagulation had more AKI (OR 2.70, OR: 2.37), pneumonia (OR: 2.89, OR: 2.46), MI (OR: 2.70, OR: 3.14), transfusion (OR: 6.94, OR: 3.16), sepsis (OR: 2.47, OR: 1.96), and aseptic loosening at 90 days (OR: 17.06, OR:7.01). However, PE (OR: 3.32) and hematoma (OR: 1.71) were only higher in the warfarin cohort. TKA instability was higher in the DOAC cohort (OR: 6.00). Conversely, patients in the control group exhibited more wound dehiscence compared to the warfarin group (OR: 0.28), and higher rates of revision surgery compared to both the DOAC (OR:0.27) and Warfarin (OR:0.31) groups at 90 days. Conclusion: Patients on DOAC and Warfarin for AF, and undergoing TKA are exposed to a higher risk of post-operative complications.