Abstract 14685: The Antiplatelet Activity of Direct Oral Anticoagulants in Acute Ischemic Stroke Patients
Introduction: Recently, in addition to warfarin, direct thrombin and direct factor Xa inhibitors have been used as oral anticoagulants for prevention of embolic stroke. While in Japan, argatroban, also a direct thrombin inhibitor, is available for the treatment of atherothrombotic stroke patients, supported by the evidence of decreasing micro thrombus from fragile atheromatous plaque.
Hypothesis: We aimed to explore whether there is any differences between direct thrombin and direct factor Xa inhibitors regarding the inhibiting effect against thrombogenesis in acute ischemic stroke (AIS) patients.
Methods: Between January 2015 and May 2016, AIS patients newly prescribed anti-thrombotic agents were consecutively screened, and 36 patients were enrolled (average age 74.0 yo). Patients who had multiple anti-thrombotic agents, consciousness disturbance, dysphagia and complications such as pneumonia and active malignancy were excluded. Blood sampling was performed at 1 and 2 weeks after the medication started. Evaluated factors were platelet aggregation with ADP, pentraxin-3 (PTX), IL-6, prothrombin time, activated partial thromboplastin time, prothrombin fragment (F1+2) and thrombin antithrombin III complex. Patients with antiplatelets were used as control.
Results: Prescribed anti-thrombotics were dabigatran (group D: n=8), apixaban (group A: n=10) and antiplatelet agents (group P: n=18). Prevalence of stroke risks was not different between group D and A. Anticoagulation activity was equally observed in group D and A. PTX and IL-6 were declined during one week in both group D and A. However, the reduction of IL-6 was higher in group D compared with group A (p=0.295: 8.5 pg/ml and 2.2 pg/ml, respectively). While 88.9% of group P patients showed reduced platelet aggregation activity, 62.5% of group D and 40.0% of group A presented moderate reduction of platelet aggregation activity.
Conclusions: This is the first report which investigated the antiplatelet activity of direct oral anticoagulants in AIS patients. Although the effect of anticoagulation was the same between dabigatran and apixaban, there is value in continuing to investigate the difference of antiplatelet effects.
- Direct factor Xa inhibitor
- Direct thrombin inhibitor
- Inflammation and inflammatory markers
- Platelet receptor blockers
Author Disclosures: T. Nakase: None. A. Suzuki: None.
- © 2016 by American Heart Association, Inc.