Pediatric Implantable Low-Shear Pulsatile Blood Pump with Physiologic Sensing and Control

Project SummaryAbstract The goal of this project is to develop high level physiological controlimprove low level dynamic piston controland develop hemodynamic sensing capabilities for the pediatric TORVADTMa unique ventricular assist system that delivers low shearsynchronouspulsatile flowusing controlled piston motion within a torus shaped pumping chamberThe pediatric TORVAD is intended for patients with a body surface area fromtombut the design can be scaled to adapt to a wide variety of patient sizes and needsLow shear in the pumped blood is managed by the relatively low speed of the pistons which are supported by hydrodynamic bearings that maintain a fixed piston torus gapThe primary operating mode delivers amL counterpulse ejectionbut the pump can also operate asynchronously to deliver full cardiac support up toL minThe system synchronizes with the heart to preserve aortic valve flow and maintains autoregulation of cardiac output by the Frank Starling mechanismThe design of the TORVAD also enables determination of differential pump pressurewithout additional sensorsThis inherent sensing capability can be used to inform patient medications and optimal pump supportThese device advantages have been confirmed in benchtop studies and acute and chronic animal experiments with an adult TORVADand results have indicated preservation of high molecular weight von Willebrand FactorThe pediatric TORVAD has been designed to exhibit these same advantagesand thus has the potential to reduce bleedingthrombus formationand strokes that are associated with the use of other pediatric ventricular assist devicesSpecific aims for Phase I areImprove the dynamic piston controlImplement dynamic pressure sensing during pump actuationandDevelop systemic vascular resistanceSVRestimationSpecific aims for Phase II areImplement physiologic control of VAD flowFabricate devices for acute and chronic animal experimentsPerform four acute animal studies to assess control algorithmspressure signal sensingand SVR estimationPerform six chronic animal studies to assess long term viability of the pediatric TORVAD and algorithms Project Narrative Clinicians are commonly faced with a life sustaining struggle between an increasing need for mechanical circulatory support in pediatric patients but devices with outcomes that are sub optimalComplications related to currently available pediatric circulatory support devices are devastatingand serious adverse event rates associated with these devices are unacceptably highThe pediatric TORVAD has the potential to significantly reduce the complications associated with ventricular assist devices including the incidence of major bleedingneurological dysfunctionand strokesits success will provide beneficial patient outcomes and allow for more widespread as well as longer term use of ventricular assist devices in pediatric patients