Statins decrease thrombin generation in patients with hypercholesterolemia.

Objective: Statins are cholesterol-lowering agents with antithrombotic effect possibly unrelated to their lipid-lowering properties. Traditional global coagulation tests failed, however, to reveal clinically relevant change after treatment. We therefore sought to investigate whether statins were able to modify thrombin generation in hypercholesterolemia.

Global coagulation in myeloproliferative neoplasms.

In spite of their recognized risk of thrombosis, patients with myeloproliferative neoplasms (MPN) show little or no abnormalities of traditional coagulation tests, perhaps because these are unable to represent the balance between pro- and anticoagulants nor the effect of platelets and blood cells. We investigated whether global tests such as thrombin generation in platelet-rich plasma (PRP) or thromboelastometry in whole blood were able to detect signs of procoagulant imbalance in MPN. The endogenous thrombin potential (ETP) of 111 patients and 89 controls was measured in PRP with platelet count adjusted to the original patient- or control-count.

Evidence that low protein C contributes to the procoagulant imbalance in cirrhosis.

Background & Aims: Cirrhosis is associated with a plasmatic procoagulant imbalance, detected in vitro by thrombin generation tests performed in the presence vs. absence of such activators of protein C as thrombomodulin or Protac. This imbalance is thought to be due to decreased protein C and increased factor VIII, but this has never been directly demonstrated.

Global hemostasis tests in patients with cirrhosis before and after prophylactic platelet transfusion.

Background/aims: Cirrhosis presents with variable degrees of thrombocytopenia that might cause bleeding during invasive procedures. Transfusion of one standard adult platelet dose is often employed to prevent bleeding in thrombocytopenia, but the threshold platelet count that is clinically effective is not well established because clinical studies and laboratory tools to judge on efficacy are insufficient. However, in vitro studies showed that patients with cirrhosis generate as much thrombin as healthy individuals provided that their platelet count is at least 100 × 10(9) /L.

Detection of the imbalance of procoagulant versus anticoagulant factors in cirrhosis by a simple laboratory method.

Unlabelled: Patients with cirrhosis possess an imbalance in procoagulant versus anticoagulant activity due to increased factor VIII and decreased protein C. This imbalance can be detected by thrombin-generation assays performed in the presence/absence of thrombomodulin (predicate assay) that are not readily available in clinical laboratories. We sought to assess this hypercoagulability with a simpler thrombin-generation assay performed in the presence/absence of Protac, a snake venom that activates protein C in a manner similar to thrombomodulin (new assay).

Abnormal Protac-induced coagulation inhibition chromogenic assay results are associated with an increased risk of recurrent venous thromboembolism.

Evaluation of the risk of recurrent venous thromboembolism (VTE) is required to determine the optimal duration of secondary prophylaxis. Application of global assays reflecting the pro- versus anti-coagulant balance in vivo would be desirable. We aimed at investigating the relationship between recurrent VTE and the Protac-induced coagulation inhibition (PICI) assay, which is based on tissue factor-induced thrombin generation measured by a chromogenic substrate.