title: Relationship between factor XII, von Willebrand factor and postoperative deep vein thrombosis.
abstract: The development of postoperative deep vein thrombosis (DVT) was studied in 45 patients subjected to major abdominal surgery, 17 of whom showed signs of DVT as defined by 125I-fibrinogen test. The preoperative levels of von Willebrand factor (F VIII RAg) and platelets were higher in these 17 patients than in those remaining free from DVT. A contributing factor in DVT development thus may be more active primary haemostasis. Preoperative F XII levels were similar in the two groups, but the post-operative drop in F XII was more pronounced in the DVT group. An inhibitor of plasminogen activation behaved similarly in both groups. C1-inhibitor, the main inhibitor of the F XII-dependent clotting and fibrinolytic pathways, showed a typical acute-phase response postoperatively, without intergroup difference. The study suggested that F XII-dependent pathways play a role in the genesis of venous thrombi, at least in the postoperative period, though whether the postoperative F XII drop was due to a role in clotting or to fibrinolysis activation remains unclear.
mesh_terms: D003172:Complement C1 / Q000032:analysis; D013505:Digestive System Surgical Procedures; D005174:Factor XII / Q000032:analysis*; D006023:Glycoproteins / Q000032:analysis; D006801:Humans; D010960:Plasminogen Activators / Q000037:antagonists & inhibitors; D015849:Plasminogen Inactivators; D011183:Postoperative Complications / Q000097:blood*; D013924:Thrombophlebitis / Q000097:blood* / Q000209:etiology; D014841:von Willebrand Factor / Q000032:analysis*
chemical_list: D003172:Complement C1; D006023:Glycoproteins; D015849:Plasminogen Inactivators; D014841:von Willebrand Factor; D005174:Factor XII; D010960:Plasminogen Activators