Dabigatran enhances platelet reactivity and platelet thrombin receptor expression in patients with atrial fibrillation. (6th February 2017)

• Record Type: Journal Article
• Authors: Achilles, A.; Mohring, A.; Dannenberg, L.; Grandoch, M.; Hohlfeld, T.; Fischer, J. W.; Levkau, B.; Kelm, M.; Zeus, T.; Polzin, A.
• Is Part Of: Journal of thrombosis and haemostasis. Volume 15:Number 3(2017)
• Page Start: 473
• Page End: 476
• Publication Date: 2017-02-06
• Subjects: dabigatran -- myocardial infarction -- platelet -- protease activated receptors -- thrombin; Thrombosis -- Periodicals; Hemostasis -- Periodicals; Blood coagulation disorders -- Periodicals; 616.1
• DOI: 10.1111/jth.13595
• Languages: English
• ISSNs: 1538-7933

Abstract

Abstract : Essentials Whether or not dabigatran enhances the risk of myocardial infarction is under discussion. We measured platelet reactivity and thrombin receptor expression in dabigatran patients. Platelet reactivity and thrombin receptor expression is enhanced during dabigatran treatment. This should be considered when choosing the optimal direct oral anticoagulant for individuals. Summary: Background: The direct oral anticoagulant (DOAC) dabigatran is a direct thrombin inhibitor. Its landmark trial, the RE‐LY study, observed a trend towards a higher incidence of myocardial infarctions (MIs) in dabigatran‐treated patients. Since then, there have been discussions on whether dabigatran increases the risk of MI. Objective: In this study, we aimed to assess platelet reactivity and platelet thrombin receptor expression in dabigatran‐treated patients. Methods: We conducted a cross‐sectional study in 13 hospitalized patients with planned initiation of dabigatran medication. Platelet reactivity was measured by light‐transmission aggregometry and platelet thrombin receptor expression was measured by flow cytometry analysis. Results: Platelet reactivity was higher after initiation of dabigatran medication as compared with baseline (baseline 44 ± 24% vs. dabigatran 70 ± 25%). Accordingly, the density of both platelet thrombin receptors (protease activated receptor [PAR]‐1 and PAR‐4) on platelets increased during dabigatran treatment (PAR1, baseline 63 ± 11% vs. dabigatran 70 ± 10%; PAR4, baseline 1.1 ± 0.5% vs. dabigatran 1.6 ± 0.9%). Conclusions: Dabigatran increases platelet reactivity by enhancing the thrombin receptor density on platelets. This finding should be considered while choosing the optimal DOAC in individualized medicine.