Journal
BRITISH JOURNAL OF HAEMATOLOGY
Volume 142, Issue 6, Pages 946-952Publisher
WILEY-BLACKWELL
DOI: 10.1111/j.1365-2141.2008.07279.x
Keywords
atrial fibrillation; warfarin; thrombin generation; International Normalized Ratio
Categories
Funding
- British Heart Foundation Funding Source: Medline
Ask authors/readers for more resources
Atrial fibrillation (AF) is a common cardiac arrhythmia with a 5-20% annual risk of stroke. Warfarin reduces this risk by at least 60%. Despite adequate anticoagulation within the target International Normalized Ratio (INR) range of 2.0-3.0, some patients still experience thrombotic and bleeding events. It is now possible to assess the intensity of anticoagulation with automated thrombin generation (TG) tests, such as the calibrated automated thrombogram (CAT). These tests were compared and an inverse relationship was found between the INR and CAT in 143 elderly AF patients. There was equally good correlation between the concentration of factors II, VII, IX and X and the INR and TG parameters. The peak thrombin was most strongly associated with the concentration of prothrombin fragment 1 + 2 in plasma. There was wide variability in TG parameters in patients with identical INR values, sometimes up to a fourfold difference. This TG variability in individuals with the same INR is not due to inflammation, at least when the latter is measured as the concentration of factor VIII coagulant activity, von Willebrand factor antigen, high sensitivity C-reactive protein and fibrinogen. It was concluded that, although the TG and INR were closely correlated there was wide variability in peak thrombin and endogenous thrombin potential in patients within the INR therapeutic range, the cause of which remains unclear.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available