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Dinkelaar J.,Haematology and Clinical Chemistry Laboratory | Patiwael S.,Sanquin Research | Harenberg J.,University of Heidelberg | Leyte A.,Haematology and Clinical Chemistry Laboratory | Brinkman H.J.M.,Sanquin Research
Clinical Chemistry and Laboratory Medicine | Year: 2014

Background: Specific mass spectrometry and direct activated factor X (Xa)- and thrombin inhibition assays do not allow determination of the reversal of anticoagulant effects of non-vitamin K direct oral anticoagulants (NOACs) by prothrombin complex concentrate (PCC). The objective of this study was the evaluation of the applicability of a variety of commercially available global coagulation assays in analyzing the reversal of NOAC anticoagulation by PCC.Methods: Plasma and whole blood were spiked with apixaban or dabigatran and PCC was added to these samples. Prothrombin time (PT), modified PT (mPT), activated partial prothrombin time (APTT), thrombography (CAT method) and thromboelastography (ROTEM, TEG) were performed.Results: Assays triggered by contact activation (APTT, INTEM) did not show inhibitor reversal by PCC. Assays triggered by tissue factor (TF) showed NOAC type and NOAC concentration dependent anticoagulation reversal effects of PCC ranging from partial normalization to overcorrection of the following parameters: clotting or reaction time (PT, mPT TEG-TF, EXTEM, FIBTEM); angle in thromboelastography (TEG-TF); thrombin generation (CAT) lag time, endogenous thrombin potential (ETP) and peak thrombin. Extent of reversal was assay reagent dependent. ETP (5 pM TF) was the only parameter showing complete reversal of anticoagulation by PCC for all NOACs ranging from 200 to 800 μg/L.Conclusions: ETP fits with the concept that reversal assessment of NOAC anticoagulation by PCC should be based on measurements on the clotting potential or thrombin generating potential of the plasma or whole blood patient sample. Low sensitivity of ETP for NOACs and its correlation with bleeding are issues that remain to be resolved.

Dinkelaar J.,Haematology and Clinical Chemistry Laboratory | Molenaar P.J.,Haematology and Clinical Chemistry Laboratory | Ninivaggi M.,Maastricht University | de Laat B.,Maastricht University | And 3 more authors.
Journal of Thrombosis and Haemostasis | Year: 2013

Background: Rivaroxaban has been approved as an antithrombotic agent for prevention of venous thromboembolism with specific indications. At present no antidote is appointed and no guidelines have been formulated for the measurement of Rivaroxaban reversal. Objectives: In the present study, we have evaluated the influence of prothrombin complex concentrate (PCC) on the anticoagulant effects of Rivaroxaban as measured by prothrombin time (PT) and thrombin generation tests (TGTs). Methods: Plasma and whole blood samples from healthy volunteers were spiked with Rivaroxaban (up to 800 μg L-1) and PCC was added to these samples in concentration ranges as used clinically to reverse the effects of vitamin K antagonists. PT, endogenous thrombin potential (ETP) and calibrated automated thrombography (CAT) assays were performed with varying tissue factor (TF) concentrations. Results: Addition of PCC to Rivaroxaban-spiked samples did not result in normalization of PT and TGT lag time/T-Lag in ETP and CAT, respectively. In contrast, normalization of ETP and CAT area under the curve did occur. However, the response to PCC addition was strongly TF concentration dependent and in whole blood less PCC was required for Rivaroxaban reversal as compared with plasma. Conclusions: Prothrombin complex concentrate does not neutralize the lengthening effect on PT and TGT lag time/T-Lag of Rivaroxaban anticoagulated blood in vitro; however, total thrombin potential could be normalized. Response of the different TGTs in this respect is assay condition dependent. Therefore, prospective studies are needed to clarify which assay condition and parameter describes in vivo hemostasis best in patients on Rivaroxaban who are treated with PCC. © 2013 International Society on Thrombosis and Haemostasis.

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