E. Moisescu *, L Ardelean *, V. Bumbea *, L. Simian **, A. Muresan *, H. Bumbea ***
* Department of Intensive Care, Emergency Hospital, Bucharest
** N. Gh. Lupu Hospital, Bucharest
*** Department of Hematology, Colțea Hospital, Bucharest
Abstract
Recombinant Factor Vlla (NovoSeven®) occurred as a treatment option for patients with hemophilia who developed inhibitors against clot1ing factors Vlll and/or IX. It ensures effective haemostasis at the site of injury, independent of the presence of FVlll and/or FIX, by forming complexes with exposed tissue factor (I’F). Tissue Factor is a membrane bound glycoprotein expressed on cells in the sub endothelium. It has a high affinity for FVlla with whom it forms complexes with important proteolytic activity. The TF: FVIIa complex activates FX to FXa leading of the generation of small amounts of thrombin (Ila)· This limited amount of thrombin subsequently activates the co factors factor V (FV) and FVIII, as well as platelets accumulated at the site of injury. The activated platel_ets expose Phosphatidyl serine on their membrane and proVIde the template for further thrombin generation.
