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Patients on continuous flow ventricular assist devices (CF-VADs) are at high risk for the development of Acquired von-Willebrand Syndrome (AVWS) and non-surgical bleeding. von Willebrand Factor (vWF) plays an essential role in maintaining hemostasis via platelet binding to the damaged endothelium to facilitate coagulation. In CF-VAD patients, degradation of vWF into low MW multimers that are inefficient in facilitating coagulation occurs and has been primarily attributed to the supraphysiological shear stress associated with the CF-VAD impeller. Methods In this review, we evaluate information from the literature regarding the unraveling behavior of surface-immobilized vWF under pulsatile and continuous flow pertaining to: (A) the process of arterial endothelial vWF production and release into circulation, (B) the critical shear stress required to unravel surface bound versus soluble vWF which leads to degradation, and (C) the role of pulsatility in on the production and degradation of vWF. Results and Conclusion Taken together, these data suggests that the loss of pulsatility and its impact on arterial endothelial cells plays an important role in the production, release, unraveling, and proteolytic degradation of vWF into low MW multimers, contributing to the development of AVWS. Restoration of pulsatility can potentially mitigate this issue by preventing AVWS and minimizing the risk of non-surgical bleeding.
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This content will become publicly available on May 28, 2026
Understanding the role of vascular stretch on modulation of VWF and ANGPT-2 in continuous flow left ventricular assist device (CF-VAD) patients
Non-surgical bleeding is a common complication in patients on continuous flow left ventricular assist device (CF-VAD) support. Angiopoietin-2 (ANGPT-2) and von Willebrand Factor (VWF) are important contributors to non-surgical bleeding.
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- Award ID(s):
- 2004475
- PAR ID:
- 10618252
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Lab on a Chip
- Volume:
- 25
- Issue:
- 11
- ISSN:
- 1473-0197
- Page Range / eLocation ID:
- 2722 to 2731
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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