%0 Journal Article
%T Anti
%A Luc Marie Joly
%A Marie H¨¦l¨¨ne Chr¨¦tien
%A Marielle Fresel
%A Paul Billoir
%A Virginie Barbay
%A V¨¦ronique Le Cam Duchez
%J Annals of Pharmacotherapy
%@ 1542-6270
%D 2019
%R 10.1177/1060028018811657
%X Background: Oral anti-Xa inhibitors have demonstrated noninferiority to vitamin K antagonists (VKAs) for the prevention of stroke in patients with atrial fibrillation and recurrent venous thromboembolism. They are associated with a decrease in major bleeding. In contrast with VKA, no coagulation monitoring is required. However, in clinical practice, determination of drug concentration is sometimes necessary. Objective: The objective of this study was to evaluate a low-molecular-weight heparin (LMWH) calibrated anti-Xa assay for the quantification of rivaroxaban and apixaban plasma concentration in emergency. Methods: The anti-Xa plasma concentration of rivaroxaban and apixaban were measured in emergency in 210 patients using STA anti-Xa liquid assay. For each plasma concentration <150 ng/mL of rivaroxaban or apixaban, an anti-Xa assay calibrated with LMWH was performed. Results: We demonstrated a significant correlation between LMWH anti-Xa activity and rivaroxaban (R2 = 0.947) or apixaban (R2 = 0.959) concentration and a significant correlation between rivaroxaban and apixaban plasma concentration (R2 = 0.972). A LMWH anti-Xa activity <0.50 IU/mL could exclude a plasma concentration of rivaroxaban and apixaban >30 ng/mL and indicate the feasibility of invasive procedure. Conclusion and Relevance: In the absence of a specific test, LMWH-calibrated anti-Xa assay could be used to determine the presence and evaluate the plasma concentration of oral anti-Xa inhibitors. However, these initial findings require confirmation using other chromogenic calibrated oral anti-Xa assays
%K factor Xa inhibitors
%K bleeding
%K drug screening
%K correlation between anticoagulant measurement
%K laboratory testing
%U https://journals.sagepub.com/doi/full/10.1177/1060028018811657