Series Multiblood Pump Design With Dual Activation for Pediatric Patients With Heart Failure

Abstract

The translational development of pediatric ventricular assist devices (VADs) lags years behind adult device options, negatively impacting pediatric patient outcomes. To address this need, we are developing a novel, series-flow, double-blood pump VAD that integrates an axial and centrifugal pump into a single device. The axial pump is used for initial circulatory assistance in younger patients; then, an internal activation mechanism triggers the centrifugal pump to activate in line with the axial pump, providing additional pressure and flow to match pediatric patient growth cycles. Here, we focused on the design and improvement of the device flow paths through computational analysis and in vitro hydraulic testing of a prototype. We estimated pressure-flow generation, fluid scalar stresses, and blood damage levels. In vitro hydraulic tests correlated well with shear stress transport (SST) predictions, with an average deviation of 4.5% for the complex, combined flow path. All data followed expected pump performance trends. The device exceeded target levels for blood damage in the blade tip clearances, and this must be both investigated and addressed in the next design phase. These study findings establish a strong foundation for the future development of the Drexel Double-Dragon VAD.