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Updated: Jun 2, 2026
03:53
Extracellular Vesicle Tissue Factor Activity Assay
Published on: December 29, 2023
Activated factor XI and tissue factor in aortic stenosis: links with thrombin generation
Joanna Luszczak1, Anetta Undas, Matthew Gissel
1Institute of Cardiology, Jagiellonian University School of Medicine, Krakow, Poland.
Summary
Active tissue factor (TF) and factor (F)XIa were found in patients with aortic stenosis, particularly severe cases. These factors correlate with increased thrombin generation and disease severity.
Area of Science:
- Cardiovascular Medicine
- Hemostasis and Thrombosis
Background:
- Previous studies identified active tissue factor (TF) and factor (FXIa) in cardiovascular disease patients.
- The presence and significance of these factors in aortic stenosis were previously unevaluated.
Purpose of the Study:
- To assess plasma TF and FXIa activity in patients with aortic stenosis.
- To determine the relationship between TF/FXIa activity and aortic stenosis severity.
Main Methods:
- Evaluated 54 consecutive aortic stenosis patients (38 severe, 16 moderate).
- Measured plasma TF and FXIa activity using clotting assays with inhibitory monoclonal antibodies.
- Assessed prothrombin fragment 1.2 as a marker of thrombin generation.
Main Results:
- TF activity was detected in 25.9% of patients (34.2% severe AS), FXIa in 22.2% (primarily severe AS).
- All patients with FXIa also had detectable TF.
- Severe AS patients with TF showed higher transvalvular gradients and elevated thrombin generation markers (prothrombin fragment 1.2).
Conclusions:
- TF and FXIa activity are present in aortic stenosis patients for the first time, predominantly in severe cases.
- These activities correlate with increased thrombin generation in severe aortic stenosis.
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