A Novel Hybrid Membrane VAD as First Step Toward Hemocompatible Blood Propulsion

Ann Biomed Eng. 2021 Feb;49(2):716-731. doi: 10.1007/s10439-020-02590-1. Epub 2020 Sep 8.

Abstract

Heart failure is a raising cause of mortality. Heart transplantation and ventricular assist device (VAD) support represent the only available lifelines for end stage disease. In the context of donor organ shortage, the future role of VAD as destination therapy is emerging. Yet, major drawbacks are connected to the long-term implantation of current devices. Poor VAD hemocompatibility exposes the patient to life-threatening events, including haemorrhagic syndromes and thrombosis. Here, we introduce a new concept of artificial support, the Hybrid Membrane VAD, as a first-of-its-kind pump prototype enabling physiological blood propulsion through the cyclic actuation of a hyperelastic membrane, enabling the protection from the thrombogenic interaction between blood and the implant materials. The centre of the luminal membrane surface displays a rationally-developed surface topography interfering with flow to support a living endothelium. The precast cell layer survives to a range of dynamically changing pump actuating conditions i.e., actuation frequency from 1 to 4 Hz, stroke volume from 12 to 30 mL, and support duration up to 313 min, which are tested both in vitro and in vivo, ensuring the full retention of tissue integrity and connectivity under challenging conditions. In summary, the presented results constitute a proof of principle for the Hybrid Membrane VAD concept and represent the basis for its future development towards clinical validation.

Keywords: Endothelialization; Hyperelastic membrane; VAD; Wall deformation; Wall shear stress.

MeSH terms

  • Animals
  • Cells, Cultured
  • Coronary Circulation
  • Endothelial Cells / physiology
  • Equipment Design
  • Heart-Assist Devices*
  • Hydrodynamics
  • Membranes, Artificial
  • Sheep

Substances

  • Membranes, Artificial