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  • von Willebrand Factor and Angiopoietin-2 are Sensitive Biomarkers of Pulsatility in Continuous-Flow Ventricular Assist Device Patients
Title: von Willebrand Factor and Angiopoietin-2 are Sensitive Biomarkers of Pulsatility in Continuous-Flow Ventricular Assist Device Patients
Nonsurgical bleeding occurs in a significant proportion of patients implanted with continuous-flow ventricular assist devices (CF-VADs) and is associated with nonphysiologic flow with diminished pulsatility. An in vitro vascular pulse perfusion model seeded with adult human aortic endothelial cells (HAECs) was used to identify biomarkers sensitive to changes in pulsatility. Diminished pulsatility resulted in an ~45% decrease in von Willebrand factor (vWF) levels from 9.80 to 5.32 ng/ml (n = 5, p < 0.05) and a threefold increase in angiopoietin-2 (ANGPT-2) levels from 775.29 to 2471.93 pg/ml (n = 5, p < 0.05) in cultured HAECs. These changes are in agreement with evaluation of patient blood samples obtained pre-CF-VAD implant and 30-day postimplant: a decrease in plasma vWF level by 50% from ~45.59 to ~22.49 μg/ml (n = 15, p < 0.01) and a 64% increase in plasma ANGPT-2 level from 7,073 to 11,615 pg/ml (n = 8, p < 0.05). This study identified vWF and ANGPT-2 as highly sensitive to changes in pulsatility, in addition to interleukin-6 (IL-6), IL-8, and tumor necrosis-α (TNF-α). These biomarkers may help determine the optimal level of pulsatility and help identify patients at high risk of nonsurgical bleeding.  more » « less
Award ID(s):
2004475
PAR ID:
10416597
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Wolters Kluwer
Date Published:
Journal Name:
ASAIO Journal
Volume:
Publish Ahead of Print
ISSN:
1058-2916
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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