Dabigatran Timing After Neuroendovascular Procedures and Clotting Outcomes

Background Patients undergoing complex neuroendovascular procedures often require direct oral anticoagulants (DOACs) in addition to antiplatelet therapy to mitigate thrombotic risk. To minimize bleeding risk post‐procedure, the 2023 Society of NeuroInterventional Surgery guidelines recommend resuming anticoagulation when thrombotic risk exceeds bleeding risk. European Society of Cardiology/European Heart Rhythm Association 2021 recommendations take a time‐based approach supporting a 24‐48 hour delay to DOAC initiation. The focus is on initiation rather than the time required to achieve therapeutic anticoagulation. Methods We prospectively enrolled patients undergoing planned neuroendovascular aneurysm repair, mostly with flow diverter stent, or intracranial venous stenting and started on dabigatran post‐procedure. We evaluated the time required for dabigatran to achieve therapeutic anticoagulation in this population. Individual clotting times were measured using ClotChek (Perosphere Technologies, Danbury, CT, USA), a point‐of‐care device sensitive to DOACs. Measurements occurred at discharge (≈2 days after the first dabigatran dose) and again between 5 to 60 days post‐administration. Results Fifteen patients (mean age 61 years; majority intracranial aneurysm repair with flow diverter stents) were included in the analysis. Most received dabigatran 150 mg twice daily. At 2 days, the median clotting time was 238 seconds and below the therapeutic threshold (291 seconds). At 6‐9 and 14 days, clotting times were 423 and 469 seconds respectively, all consistent with therapeutic anticoagulation. Furthermore, linear regression indicates that patients would only exceed the upper limit of normal following day 3, post‐administration (Figure 1; arrow indicates intersection of best fit line and upper limit of normal clotting times). Conclusion DOAC pharmacokinetic steady state research has guided recommendations around post‐procedural initiation. To date, time to DOAC anticoagulation effect has not been available to guide clinical decisions. Given that patients are not achieving therapeutic anticoagulation for >2 days after dabigatran initiation, starting dabigatran earlier post‐procedure may be reasonable. This may ensure patients are properly anticoagulated before discharge and therefore protected from ischemic stroke risk. Individual clotting time measurement may help clinicians balance the risk of bleeding and thrombotic events post‐procedure. Further studies are warranted to refine periprocedural anticoagulation strategies in this high‐risk population.