011 Insights from endogenous thrombin generation in patients undergoing percutaneous coronary intervention. A cohort study

BackgroundDetermination of appropriate dosing of antithrombotic drugs is difficult, and clinical studies to define appropriate monitoring techniques are needed.ObjectiveWe compared the endogenous thrombin potential (ETP) in patients planning to undergo percutaneous coronary intervention (PCI) being pre-treated with a combination of two or three antiplatelet agents and with fondaparinux or unfractionated heparin (UFH). Pre-treatment was dependent upon clinical presentation. Calibrated Automated Thrombography was performed in voluntary blood donors and in patients submitted to PCI. Thrombin generation was studied in platelet poor plasma by a fluorimetric technique.Patients/MethodsA total of 152 patients were included. Group 1 patients were pre-treated with aspirin alone, group 2 were pre-treated with aspirin and clopidogrel, group 3 were treated with a combination of aspirin, clopidogrel, and 2.5 mg fondaparinux, group 4 were treated with aspirin, clopidogrel, 2.5 mg fondaparinux, and tirofiban, and group 5 received a bolus of 50 IU/kg UFH plus antiplatelet agents.ResultsCompared with voluntary blood donors, there was a significant decrease in ETP in group 2. The addition of fondaparinux (group 3) induceda 24% decrease in ETP; a further 25% decrease in ETP was observed between groups 3 and 4. No thrombin generation was observed after UFH treatment.ConclusionAssessment of thrombin generation is potentially very useful in the setting of PCI, where a combination of antiplatelet agents and an anticoagulant is mandatory