Introduction: Edoxaban, alongside other non-vitamin K antagonist oral anticoagulants (NOAC), is increasingly used for stroke prevention in patients with atrial fibrillation. Despite treatment, stroke rate in these patients remains one to two percent per year. In this growing population of edoxaban/NOAC-treated stroke patients, rapid assessment of coagulation would be useful to guide the decision for thrombolysis or reversal therapy in case of a neurovascular emergency. However, no data exists on the effect of edoxaban on available point-of-care test (POCT) systems.
Hypothesis: Test assays of the commercially available CoaguChek® (CC) and Hemochron® are able to detect clinically relevant concentrations of edoxaban in a blood sample.
Methods: We studied patients receiving their first dose of edoxaban. Subjects receiving other anticoagulants were excluded. Six blood samples were collected from each patient: before drug intake, 30 minutes, one, two, and eight hours after intake, as well as before the next dose. Coagulation-POCT and mass spectrometry for gold standard-determination of edoxaban plasma concentration were performed at each time point.
Results: 120 blood samples from 20 edoxaban-treated patients were analyzed. Edoxaban concentrations ranged from 0 to 302ng/mL. CC-INR ranged from 0.9 to 2.3. Pearson’s correlation coefficient showed a strong correlation between CC-INR and edoxaban concentrations (r=0.73). Edoxaban concentrations > 30ng/mL (threshold for thrombolysis according to the European Stroke Organisation) were detected by CC-INR ≥ 1.1 with 96% sensitivity and 44% specificity (89% sensitivity and 88% specificity for CC-INR ≥ 1.2; AUC=0.92).
Conclusions: Our study represents the first systematic evaluation of coagulation POCT in edoxaban-treated patients. Available coagulation POCT devices may be able to reliably detect clinically relevant edoxaban concentrations in blood samples of stroke patients in the emergency setting. In addition to edoxaban-POCT analyses, we will present further data on NOAC-specific POCT from our SPOCT-NOAC study.