Numerical modeling of platelet margination and its impact on left ventricular assist device thrombogenicity

ORAL

Abstract

We investigate platelet margination and activation, and their role in the thrombogenicity of Left Ventricular Assist Device (LVAD) therapy. Using a novel model of platelet margination that accounts for the exclusion forces exerted by the spatial gradient of red blood cell concentration, we explore the impact of margination on the thrombogenicity in LVAD outflow graft as well as in the aortic arch region. Platelet microenvironment hemodynamics (instantaneous shear exposure, shear stress history, residence time) has been shown to be a dominant factor contributing to thrombogenesis in LVAD patients. Margination has been experimentally observed to occur in vessels with millimeter-size diameters and at shear rates relevant to LVAD flows. We elucidate the impact that platelet-red blood cell interactions have in platelet transport in the ascending aorta and the great vessels towards the brain to understand the high incidence of thromboembolic stroke in LVAD patients compared to thrombosis in other distal vessels, such as the renal or hepatic arteries. This investigation provides a validated model to be used on patient-specific vasculature reconstructions, as part of a wider effort to discover minimally thrombogenic LVAD implantation configurations and flow control strategies.

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Presenters

  • Rodrigo Osuna Orozco

    Univ of Washington, Mechanical Engineering Department, University of Washington, University of Washington

Authors

  • Rodrigo Osuna Orozco

    Univ of Washington, Mechanical Engineering Department, University of Washington, University of Washington

  • Venkat Keshav Chivukula

    Department of Mechanical Engineering, University of Washington, Department of Mechanical Engineering, University of Washington, Seattle, WA, USA, University of Washington, Department of Mechanical Engineering, University of Washington

  • Alberto Osuna Aliseda

    University of Washington, Department of Mechanical Engineering, University of Washington, Department of Mechanical Engineering, University of Washington, Seattle, WA, USA, Department of Neurological Surgery, University of Washington, Seattle, WA, USA, Mechanical Engineering Department, University of Washington, Department of Mechanical Engineering, University of Washington, Seattle, WA, USA, Mechanical Engineering, University of Washington, Seattle, USA