How to deal with interference on heparin anti-Xa activity caused by oral factor FXa inhibitors: communication from the ISTH SSC Subcommittee on Control of Anticoagulation
Nicolas Gendron 1),2),3); Adam Cuker 4); Robert C. Gosselin 5); Lana A. Castellucci 6); Jecko Thachil 7).
1) Paris Cité University, INSERM, Paris Cardiovascular Research Centre, Team Endotheliopathy and Hemostasis disorders, Paris, France
2) Hematology Department, Hôpital européen Georges Pompidou, Assistance Publique Hôpitaux de Paris-Centre Université Paris Cité (APHP-CUP), Paris, France
3) F-CRIN INNOVTE, Saint-Étienne, France
4) Department of Medicine and Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
5) Hemostasis and Thrombosis Center, University of California, Davis Health System, Sacramento, California, USA
6) Department of Medicine, Ottawa Hospital Research Institute at the University of Ottawa, Ontario, Canada
7) MAHSC, University of Manchester, Oxford Road, Manchester, United Kingdom
Abstract
Monitoring unfractionated heparin (UFH) to ensure effective anticoagulation may be performed using anti-factor Xa activity (anti-Xa) instead of the activated partial thromboplastin time. However, in patients who have been treated with oral factor (F)Xa inhibitors (apixaban, rivaroxaban, and edoxaban) while switching to UFH therapy, there is a risk that these oral anti-FXa drugs could interfere with UFH-calibrated anti-Xa monitoring. This may lead to inappropriate anticoagulation management. This report of the International Society on Thrombosis and Haemostasis (ISTH) Subcommittee on Control of Anticoagulation summarizes the evidence on the risk of interference from previous treatment with oral FXa inhibitors and UFH anti-Xa after heparin initiation. This communication provides pragmatic recommendations for UFH initiation and management with anti-Xa monitoring after switching from oral FXa inhibitors.