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Updated: Jan 2, 2026

Rapid Point-of-Care Assay of Enoxaparin Anticoagulant Efficacy in Whole Blood
Published on: October 12, 2012
Heparins: A Shift of Paradigm
H Coenraad Hemker1, Raed Al Dieri1, Suzette Béguin1
1Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands.
Heparins primarily inhibit thrombin generation via anti-thrombin (aIIa) activity, not anti-factor Xa (aXa). Measuring endogenous thrombin potential (ETP) could personalize heparin dosing to reduce thrombosis and bleeding risks.
Area of Science:
- Pharmacology
- Hematology
- Biochemistry
Background:
- Heparins are crucial anticoagulants.
- Their efficacy is linked to inhibiting thrombin generation.
- Current understanding emphasizes anti-thrombin (aIIa) activity over anti-factor Xa (aXa) activity for unfractionated heparin (UFH) and low molecular weight heparin (LMWH) with low aXa/aIIa ratios.
Purpose of the Study:
- To investigate the role of endogenous thrombin potential (ETP) in heparin therapy.
- To explore the potential for individualizing heparin dosage based on ETP.
- To highlight the importance of aIIa activity in determining heparin's therapeutic potency.
Main Methods:
- Measurement of endogenous thrombin potential (ETP).
- Assessment of heparin's anti-thrombin (aIIa) and anti-factor Xa (aXa) activities.
- Analysis of the concentration of the high-affinity antithrombin-binding pentasaccharide (HA5) domain.
Main Results:
- Heparin's inhibition of ETP is mainly due to aIIa activity.
- A direct relationship exists between ETP and risks of thrombosis and bleeding.
- Individual plasma responses to heparin vary significantly.
Conclusions:
- Heparin dosage individualization based on ETP may improve safety and efficacy.
- Laboratory methods for ETP and active domain concentration can characterize heparin and guide therapy.
- Wider adoption of these robust tests is needed to advance heparin therapy.
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