ReviewThrombosis journal2021
Replacement of traditional prothrombin time monitoring with the new Fiix prothrombin time increases the efficacy of warfarin without increasing bleeding. A review article.
Review in Thrombosis journal, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
6 citing papers in PubMed, 7 citations in OpenAlex.
- Challenges in PT/INR harmonization across the total testing process.Biochemia medica · 2026Review
- FIIX-based vitamin K antagonist monitoring: the promise of improved anticoagulation stability and clinical outcomes in mechanical heart valve patients.Thrombosis journal · 2026Article
- Reply: factor II/X-guided warfarin monitoring for congenital factor VII deficiency after mechanical valve replacement.Thrombosis journal · 2026Article
- Low incidence of thromboembolism with Fiix-monitored warfarin compared to conventional warfarin and DOACs in patients with AF.Blood vessels, thrombosis & hemostasis · 2025Article
- Innovative Diagnostic Solutions in Hemostasis.Diagnostics (Basel, Switzerland) · 2024Review
- Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 4 institutions in 2 countries.
Funding
Abstract
The antithrombotic effect of vitamin K antagonists (VKA) depends on controlled lowering of the activity of factors (F) II and X whereas reductions in FVII and FIX play little role. PT-INR based monitoring, however, is highly influenced by FVII, which has the shortest half-life of vitamin K-dependent coagulation factors. Hence, variability in the anticoagulant effect of VKA may be partly secondary to an inherent flaw of the traditional monitoring test itself. The Fiix prothrombin time (Fiix-PT) is a novel test that is only sensitive to reductions in FII and FX and is intended to stabilize the VKA effect. Two clinical studies have now demonstrated that when warfarin is monitored with the Fiix-PT based normalized ratio (Fiix-NR) instead of PT-INR, anticoagulation is stabilized and less testing and fewer dose adjustments are needed. Furthermore, the relative risk of thromboembolism was reduced by 50-56% in these studies without an increase in major bleeding.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.