Abstract Number: PB0975
Meeting: ISTH 2021 Congress
Theme: Platelets and Megakaryocytes » Platelet Function and Interactions
Background: Balancing the prevention of thrombotic events vs. the risk of bleeding associated with anticoagulant and antiplatelet therapies in patients with coexisting atrial fibrillation and coronary artery disease is controversial. Recent availability of direct oral anticoagulants and more potent antiplatelet agents has further increased the complexity of this challenge.
Aims: To evaluate the effects of apixaban (Apix), added at different concentrations to blood samples from patients under antiplatelet therapies on the hemostatic and prothrombotic functions of platelets.
Methods: Blood samples were obtained from: control healthy donors (n=24), and patients treated with aspirin (ASA, n=21), ASA and clopidogrel (ASA+CLOPI, n=8), or ASA and ticagrelor (ASA+TICA, n=20). Samples were incubated with Apix at 0, 40, and 160 ng/mL. We applied:
i) Thrombin generation assay, to analyze the contribution of platelets to thrombin generation;
ii) Rotational thromboelastometry (ROTEM), to evaluate clot formation;
iii) Microfluidic studies in perfusion devices to evaluate platelet and fibrin interactions with a collagen + tissue factor substrate.
Results: Thrombin generation decreased progressively with Apix concentrations, especially for Apix 160ng/mL with ASA+TICA (p<0.01). Apix caused dose-dependent alterations of the viscoelastic parameters in ROTEM (p<0.01 at Apix 160ng/mL for all groups). Microfluidic studies showed a reduction in the surface covered by platelets, platelet aggregates volumes and fibrin deposition for both Apix concentrations in all groups. Apix 40ng/mL showed moderate inhibitory antithrombotic actions on all the tests. At this concentration, Apix preserved better the hemostatic function of platelets with all antiplatelet regimes explored.
Conclusions: Combined presence of Apix with antiplatelet strategies showed inhibitory action on all parameters evaluated. The suppressed action on thrombin generation, fibrin and platelet aggregate formation was more evident at the highest Apix concentration. Apix 40ng/mL demonstrated a consistent antithrombotic action, but proved more respectful at preserving hemostatic parameters with all antiplatelet regimens.
Grants: BMS ERISTA, FIS PI19/00888.
To cite this abstract in AMA style:
Martinez-Sanchez J, Castrillo L, Jerez D, Torramade-Moix S, Palomo M, Mendieta G, Diaz-Ricart M, Roque M, Escolar G. Effects of Different Concentrations of Apixaban Combined with Antiplatelet Therapies on Platelet Hemostatic and Thrombogenic Functions. Ex-vivo Exploratory Study in Patients under Various Antiplatelet Regimens [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/effects-of-different-concentrations-of-apixaban-combined-with-antiplatelet-therapies-on-platelet-hemostatic-and-thrombogenic-functions-ex-vivo-exploratory-study-in-patients-under-various-antiplatelet/. Accessed December 6, 2023.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/effects-of-different-concentrations-of-apixaban-combined-with-antiplatelet-therapies-on-platelet-hemostatic-and-thrombogenic-functions-ex-vivo-exploratory-study-in-patients-under-various-antiplatelet/