Willebrand Factor
Also written as VWF.
Clotting: Factors V, VII, VIII, IX, X, XII, von Willebrand factor and fibrinogen (doubles) rise; antithrombin III and protein S fall; fibrinolysis is reduced — A hypercoagulable state: protects against postpartum haemorrhage but raises the risk of venous thromboembolism
What our notes say
- Clotting: Factors V, VII, VIII, IX, X, XII, von Willebrand factor and fibrinogen (doubles) rise; antithrombin III and protein S fall; fibrinolysis is reduced — A hypercoagulable state: protects against postpartum haemorrhage but raises the risk of venous thromboembolism (Physiological changes in pregnancy)
- The final step is platelet the detection of transient ST-segment elevation with rest\naggregation (3), in which fibrinogen (or von Willebrand factor)\npain. (Harrisons Pulmonary and Critical Care Medicine)
- Other forms of HUS/TTP are related to a decrease in should always be managed with the lowest FIO2 that is sufprocessing of von Willebrand factor by a protease called ficient to maintain hemoglobin saturation. (Harrisons Pulmonary and Critical Care Medicine)
- VWD is caused by a defect in or deficiency of von Willebrand factor (VWF). (Haemostasis)
- Platelet adhesion: platelets stick to exposed collagen through von Willebrand factor (GPIb). (Internal Medicine End of Semester CAT (MBChB 4): haematology and renal, 30 MCQs )
- Endothelium (von Willebrand factor): Mediates platelet adhesion under shear (Thrombocytopenia and platelet disorders)
Study material on Willebrand Factor
- Haemostasis
- Haemostasis
- Platelet Disorders — Notes
- Bleeding Disorders
- 3a bleeding disorders
- Harrisons Pulmonary and Critical Care Medicine
- Coagulation disorders
- Haemostasis & Coagulation: Platelet Function & Bleeding Disorders — Notes
- Harrisons Cardiovascular Medicine 2nd Edition 2
- DIC
Practice questions on Willebrand Factor
Main function of von Willebrand factor?
- Binds platelets to collagen
- Inhibits thrombin
- Activates fibrinogen
- Cross-links fibrin
Answer: A. vWF acts as a bridge between exposed subendothelial collagen and platelet GPIb receptors, initiating primary haemostasis.
Von Willebrand factor (vWF) has two main functions
- Platelet adhesion to subendothelium and Factor VIII carrier
- Activating thrombin and fibrin crosslinking
- Fibrinolysis activation and platelet aggregation
- Factor X activation and fibrinogen binding
Answer: A. vWF bridges platelet GPIb receptors to exposed collagen and protects Factor VIII from degradation in plasma.