Transitioning of patients from direct acting oral anticoagulant to heparin: impact on laboratory testing
File(s)
Published version
Author(s)
Jayakody Arachchillage, Deepa
Vinayagam, Saravanan
Parsons, Annie
Karawitage, Nilanthi
Laffan, Mike
Type
Journal Article
Abstract
Direct oral anticoagulants (DOACs), including direct thrombin inhibitors (dabigatran) and direct factor Xa inhibitors (apixaban, rivaroxaban, edoxaban), have transformed anticoagulant management in recent years due to their predictable pharmacodynamics, rapid onset of action, and fixed dosing without the need for routine laboratory monitoring. Unfractionated heparin (UFH) remains the anticoagulant of choice for patients who are acutely unwell and treated in intensive care units due to its short half-life, reversibility, ease of dose titration, and nonrenal dependent excretion. It is therefore not uncommon for an individual's anticoagulation management to require rapid changing from DOAC to UFH. Due to UFH's complex pharmacokinetics, including nonspecific binding to acute phase proteins and dose-dependent clearance, careful laboratory monitoring, generally with activated partial thromboplastin time (APTT) or anti-factor Xa (anti-Xa) activity, is necessary. When transitioning from a DOAC to UFH, overlapping pharmacologic effects can significantly interfere with coagulation assays, particularly if residual DOAC levels persist at the time UFH is initiated. DOACs can prolong the APTT and elevate anti-Xa activity, leading to overestimation of UFH activity, inappropriate dose adjustments, and increased risk of bleeding or thromboembolic events. Here, we examine the laboratory implications of transitioning from DOAC therapy to UFH, with a focus on the performance and interpretation of APTT and anti-Xa assays in the presence of residual DOAC levels and how to overcome the interference of DOAC in UFH monitoring. We suggest an algorithm to follow during this transition.
Date Issued
2025-11-13
Date Acceptance
2025-09-12
Citation
Seminars in Thrombosis and Hemostasis, 2025
ISSN
0094-6176
Publisher
Thieme Gruppe
Journal / Book Title
Seminars in Thrombosis and Hemostasis
Copyright Statement
© 2025. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/)
License URL
Identifier
10.1055/a-2734-2293
Publication Status
Published online
Date Publish Online
2025-11-13