In-vitro and In-vivo testing of the BiVACOR Rotary BiVAD/TAH

摘要

BiVACOR is a novel rotary Bi-Ventricular Assist Device / Total Artificial Heart (BiVAD/TAH) undergoing development to treat global end stage heart failure. The design includes left and right vanes positioned on a shared rotating hub to form a double-sided magnetically and hydro-dynamically suspended centrifugal impeller. The performance of the device was assessed in a pulsatile mock circulation loop replicating end stage bi-ventricular heart failure, and was shown to restore flow-from pathological (2L/min) to normal levels (5L/min). A subsequent series of 9 acute in-vivo trials successfully tested the functional response of the device to a number of clinical conditions during bi-ventricular assistance and total heart replacement. The unique ability of the device to mimic the frank-starling effect and prevent ventricular collapse, by altering the left/right chamber outflows with impeller axial displacements in response to changing venous return, has also been evaluated. The systemic and pulmonary circulation of each sheep was successfully supported during conditions of normal, failing and absent heart function. Simultaneous alteration of the left/right outflow was successful in matching the flow requirements of both circulatory systems and maintaining adequate atrial filling pressures. This device will provide a suitably miniature and relatively inexpensive long term rotary device for patients who require bi-ventricular support and/or total heart replacement.