Enhanced fibrinogenolysis after dabigatran in normal healthy volunteers
Rapina Ambarita, Zulfikar Lubis, Herman Hariman
Background: Dabigatran is an oral anticoagulant which differs from warfarin that it does not affect vitamin K dependent factors. It is grouped under the direct oral anticoagulant drug (DOAC) and acts as direct thrombin inhibitor. There is another DOAC which acts at different pathway and known as anti-factor X: a. Dabigatran as a direct thrombin inhibitor will theoretically not produce fibrinogenolysis. Itis therefore considered as safe from bleeding and does not need blood test for monitoring. Contradictory to this belief, there were reports that dabigatran produced severe bleeding in some cases. Objectives: The aim of the study is to find out whether dabigatranas it is claimed to be safe from bleeding is a true direct thrombin inhibitor and does not produces fibrinogenolysis. Materials and Methods: 15 normal volunteers were recruited in this study and venous blood samples were taken before dabigatran, 2 hours and 30 minutes after dabigatran, and 24 hours following its administration for the investigations of fibrinogen, thrombin time, and d-dimer. Results and Discussion: Mean ± SEMoffibrinogenbefore dabigatrantends to reduce2 hours and 30 minutes after its administration 341.5 ± 17.9 and 306.9 ± 32.2 mg/dl respectively p>0.05 and becomes significant after 24 hours, 284.6± 19.6 mg/dl, p<0.05.d-dimer remains unchanged during the whole period, p>0.05 whereas thrombin time shows a classical prolongation of the test during dabigatran administration. Conclusion: This study concludes that dabigatran produces enhanced fibrinogenolysis 24 hours after the administration but not fibrinolysis. In addition, thrombin time can not be used to detect the fibrinogenolysis. So, we recommend that fibrinogen should be measured for dabigatran monitoring.