Abstract Number: PB0343
Meeting: ISTH 2021 Congress
Background: Reversal of anticoagulation by vitamin K antagonists (VKAs) is obtained by administration of four-factor prothrombin complex concentrates (4F-PCCs). Thrombin generation assay (TGA) has been shown to be suitable for the in vivo evaluation of the hemostatic potency of 4F-PCCs. Commercially available 4F-PCCs contain heparin at different levels. Consequently, TGA results obtained for in vitro samples will be biased and may not fully reflect the clinical efficacy of 4F-PCCs observed. Removal of heparin by anion exchange adsorption has been described but this procedure could potentially alter the complex composition of 4F-PCCs. Heparin neutralization with protamine sulphate requires exact titration in order not to interfere with the determination of the hemostatic potency.
Aims: Description of a robust method to remove the inhibitory heparin effect on the TGA.
Methods: A heparin-containing 4F-PCC sample was mixed with Heparinase and incubated for 5 min at room temperature. Then, the Technothrombin TGA (Technoclone) was done using the fully automated coagulation analyzer Ceveron® (Technoclone). Normal and VKA anticoagulated plasma was used at a final heparinase concentration of 1.25 U/mL at two trigger levels. The adequate heparinase concentration was determined by investigating a concentration series of heparinase, ranging from 0.25 to 2.5 U/mL.
Results: Heparinase at a final concentration of 1.25 U/mL completely removed the heparin interference. At this heparinase level, there was only moderate influence on the characteristic TGA readouts lag time, peak thrombin, endogenous thrombin potential and velocity index for all conditions tested. After heparinase treatment, the heparin-containing 4F-PCC concentrate demonstrated dose-dependent TGA response, which was not the case when this treatment was omitted.
Conclusions: Enzymatic breakdown of heparin by heparinase efficiently removed the heparin interference observed during the in vitro TGA testing of 4F-PCCs. Heparinase treatment can easily introduced in existing test procedures and will increase the significance of data generated with TGA.
To cite this abstract in AMA style:
Weber A, LLusa M, Gritsch H, B Binder N. Heparin Interference of the Thrombin Generation Assay Can Be Eliminated by Heparinase Treatment [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/heparin-interference-of-the-thrombin-generation-assay-can-be-eliminated-by-heparinase-treatment/. Accessed April 19, 2024.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/heparin-interference-of-the-thrombin-generation-assay-can-be-eliminated-by-heparinase-treatment/