0000000000583422
AUTHOR
Sylvia Haas
Prothrombinase-Induced Clotting Time Assay for Determination of the Anticoagulant Effects of Unfractionated and Low-Molecular-Weight Heparins, Fondaparinux, and Thrombin Inhibitors
The prothrombinase-induced clotting time assay (PiCT, Pentapharm, Basel, Switzerland) is a clotting assay sensitive to factor Xa and factor IIa inhibitors. It is based on the addition of factor Xa and snake venom RVV-V (Russell viper venom factor V activator) specifically activating factor V and phospholipids to platelet-poor plasma. Following an incubation time, the mixture is recalcified and the clotting time is determined. An almost linear dose-response and high sensitivity of the assay for unfractionated heparin (UFH), low-molecular-weight heparins (LMWHs), r-hirudin, and argatroban was found. Fondaparinux showed a nonlinear dose-response. By using ex vivo samples, the following Pearson…
Predictive value of venous thromboembolism (VTE)-BLEED to predict major bleeding and other adverse events in a practice-based cohort of patients with VTE: results of the XALIA study
Summary Venous thromboembolism (VTE)‐BLEED, a decision tool for predicting major bleeding during chronic anticoagulation for VTE has not yet been validated in practice‐based conditions. We calculated the prognostic indices of VTE‐BLEED for major bleeding after day 30 and day 90, as well as for recurrent VTE and all‐cause mortality, in 4457 patients enrolled in the international, prospective XALIA study. The median at‐risk time was 190 days (interquartile range 106–360). The crude hazard ratio (HR) for major bleeding after day 30 was 2·6 [95% confidence interval (CI) 1·3–5·2] and the treatment‐adjusted HR was 2·3 (95% CI 1·1–4·5) for VTE‐BLEED high (versus low) risk patients: the correspondi…