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Updated: Dec 12, 2025
08:30
Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation
Published on: August 14, 2017
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[Acquired von Willebrand syndrome]
Masaki Hayakawa1, Masanori Matsumoto1
1Department of Transfusion Medicine, Nara Medical University.
Summary
Acquired von Willebrand syndrome (AVWS) is a rare bleeding disorder linked to various conditions. Cardiovascular diseases, particularly aortic valve stenosis and LVADs, are increasingly associated with AVWS due to shear stress mechanisms.
Area of Science:
- Hematology
- Internal Medicine
- Cardiology
Background:
- Von Willebrand disease (VWD) is a common inherited bleeding disorder.
- Acquired von Willebrand syndrome (AVWS) is less frequent but associated with numerous conditions, including lymphoproliferative, cardiovascular, myeloproliferative, neoplastic, and autoimmune disorders.
- Recent studies highlight AVWS in aortic valve stenosis (AS) and left ventricular assist devices (LVADs).
Purpose of the Study:
- To explore the mechanisms and associations of acquired von Willebrand syndrome (AVWS).
- To investigate the role of immune and non-immune pathways in AVWS development.
- To highlight the significant link between cardiovascular conditions and AVWS.
Main Methods:
- Review of immune-mediated mechanisms involving autoantibodies to VWF, particularly targeting high molecular weight-VWF multimers (HMW-VWFMs).
- Analysis of non-immune mechanisms, including VWF adsorption onto malignant cells and shear stress-induced proteolysis.
- Examination of shear stress in AS and LVADs, and its effect on HMW-VWFMs cleavage by ADAMTS13.
Main Results:
- Autoantibodies to VWF are implicated in AVWS associated with monoclonal gammopathies, lymphoid neoplasms, and autoimmune diseases.
- VWF can be adsorbed onto malignant cells or paraproteins, reducing its circulation.
- High shear stress in AS and LVADs increases susceptibility of HMW-VWFMs to cleavage by ADAMTS13, leading to AVWS.
Conclusions:
- AVWS can result from immune mechanisms (autoantibodies) or non-immune mechanisms (adsorption, shear stress).
- Cardiovascular diseases, especially AS and LVADs, are significant contributors to AVWS due to mechanical stress on VWF.
- A substantial number of AVWS cases are expected to be related to cardiovascular diseases.
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