Differences in Coagulation Responses to Vascular Injury Between Uninterrupted Dabigatran and Apixaban - a Clinical Prospective Randomized Study

Background The coagulation response during vascular injury with uninterrupted administration of direct oral anticoagulants (DOACs) has not been elucidated. Objective Our aim was to evaluate differences in coagulation responses after vascular injury between uninterrupted direct thrombin inhibitor and direct factor Xa inhibitor recipients. Methods Patients scheduled for catheter ablation for atrial fibrillation were randomly assigned to receive dabigatran or apixaban in this prospective, randomized, comparative, parallel-group study. Venous blood was collected three times: 180 minutes after taking the anticoagulant on the day before the procedure, before vascular punctures of the ablation procedure, and 10–15 minutes after the start of vascular punctures. Results Forty-two patients were enrolled. The prothrombin fragment 1+2 (F1+2) level, the primary endpoint, was much larger after vascular puncture in the uninterrupted dabigatran recipients (median: 83 pmol/L; interquartile range: 56–133 pmol/L) than in the uninterrupted apixaban recipients (median: 1 pmol/L; interquartile range: −3–19 pmol/L; P < 0.001). Antithrombin levels decreased after vascular puncture in dabigatran recipients, and both protein C and antithrombin levels decreased after vascular puncture in apixaban recipients. Conclusions Unlike uninterrupted apixaban, uninterrupted dabigatran does not inhibit thrombin generation in response to vascular injury.