[Monitoring of Oral Thrombin Inhibitor].

Dabigatran etexilate is a prodrug that is converted into its active metabolite, dabigatran, by hydrolysis. Dabigatran is a selective thrombin inhibitor that has been approved for the prevention of stroke in patients with non-valvular atrial fibrillation in Japan. Laboratory monitoring is not needed, but an assessment of its anticoagulant effect in certain clinical settings, such as emergency surgery, suspected overdose, or the occurrence of bleeding, is desirable. We overview the special coagulation assays, such as Hemoclot Thrombin Inhibitor (HTI), the thrombin generation assay (TGA), ecarin clotting time (ECT), ecarin chromogenic assay (ECA), prothrombinase-induced clotting time (PiCT), and activated clotting time (ACT). We also examined the relationship between dabigatran levels as determined by HTI, and the activated partial thromboplastin time (APTT) and prothrombin time (PT). APTT and PT demonstrated a positive correlation with the dabigatran levels. APTT, PT, and the combination of APTT and PT may estimate the dabigatran levels in plasma.