Implementation of a Simplistic Bivalirudin-Warfarin Transition Protocol Is Associated With Improved Achievement of INR Values Within the Therapeutic Range

Abstract

Background: Transition from bivalirudin to long-term warfarin therapy is often difficult to execute due to bivalirudin prolongation of the international normalized ratio (INR), and literature to help guide this transition is extremely limited. Objective: To assess the transition from bivalirudin to warfarin after implementation of an institution-wide transition protocol. Methods: In this retrospective quasiexperimental study, adult patients receiving bivalirudin directly followed by warfarin for nonprocedural systemic anticoagulation were evaluated to determine the frequency of successful transition to warfarin. Participants were compared before (preprotocol) and after (postprotocol) the implementation of the transition protocol. Results: A total of 39 patients met inclusion criteria and were included in the analysis (preprotocol = 19; postprotocol = 20). The percentage of patients achieving a successful transition was significantly higher in the postprotocol group compared with the preprotocol group (80.0% vs 42.1%, P = 0.015). Bleeding events were similar between the 2 groups (23.1% vs 16.7%, P = 0.689). Withholding of warfarin doses or the use of anticoagulant reversal agents or blood transfusions for supratherapeutic INR levels, surgical procedures, or drop in hemoglobin was numerically lower in the postprotocol group compared with the preprotocol group (16.7% vs 46.2%, P = 0.202). Conclusion: Implementation of a simplistic bivalirudin-warfarin transition protocol significantly increased the frequency of therapeutic INR results on bivalirudin discontinuation. Additionally, patients treated according to this protocol were less likely to have warfarin doses withheld or require reversal agents. Larger studies testing this transition strategy are warranted.