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Updated: May 30, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Persistent high factor VIII activity leading to increased thrombin generation - a prospective cohort study.
J K Ryland1, A S Lawrie, I J Mackie
1Haemostasis Research Unit, Department of Haematology, University College London, London, UK.
Elevated factor VIII (FVIII) and increased thrombin generation (TG) are linked to recurrent venous thromboembolism (VTE). These markers appear sustained, suggesting prolonged anticoagulation may benefit high-risk patients.
Area of Science:
- Hematology
- Thrombosis Research
- Vascular Medicine
Background:
- Persistently elevated factor VIII (FVIII) is a known risk factor for venous thromboembolism (VTE).
- The precise role of thrombin generation (TG) in VTE pathophysiology requires further elucidation.
- Understanding the dynamics of FVIII and TG in VTE patients is crucial for risk stratification.
Purpose of the Study:
- To investigate the relationship between factor VIII (FVIII) levels, thrombin generation test (TGT) parameters, and D-dimer in VTE patients.
- To determine if elevated FVIII and increased TG in VTE patients are transient or sustained phenomena.
Main Methods:
- Recruitment of 91 VTE patients and 52 healthy controls post-anticoagulation.
- Measurement of factor VIII (FVIII) using one-stage clotting (FVIII:C) and chromogenic (FVIII:Ch) assays.
- Assessment of thrombin generation potential using the Calibrated Automated Thrombogram (CAT) and D-dimer levels via immuno-turbidometric assay.
Main Results:
- Good agreement was observed between FVIII:C and FVIII:Ch assays (rs=0.94).
- FVIII:Ch significantly correlated with TGT Peak Thrombin (rs=0.30; p=0.004).
- Peak Thrombin was significantly higher in patients with FVIII > 200 iu/dL (p=0.04), and elevated FVIII and TG parameters were consistent over time.
Conclusions:
- High factor VIII (FVIII) levels and associated increased thrombin generation (TG) significantly elevate the risk of recurrent VTE.
- These findings suggest that elevated FVIII and TG are sustained in VTE patients.
- Prolonged anticoagulation therapy may be beneficial for VTE patients with high FVIII and increased TG.
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