Design of an Implantable Blood Pump for Mechanical Circulatory Support in Pediatric Patients

Abstract

While the use of pulsatile- and continuous-flow ventricular assist devices (VADs) has become widely accepted as an acceptable treatment for end-stage heart failure in adults over the last three decades, the technology development for pediatric-specific patients is lagging behind that of adult devices. Only one pulsatile-flow VAD has been approved for use in pediatric patients in the U.S., just five years ago [1]. One continuous-flow device was approved specific to this population under Humanitarian Device Exemption (HDE), but is not in clinical use today [2]. As continuous-flow rotary blood pumps (RBPs) have become commonplace for mechanical circulatory support (MCS) in adults due to smaller size and greater reliability, significant resources have gone into the development of RBPs for pediatric use [3]. Further, RBPs designed for adult MCS have been used off-label in pediatric patients [4]. Development of an implantable device specific to a pediatric population includes challenges of anatomic placement and fixation. We have developed a RBP for adult MCS specific to right heart failure using computational fluid dynamics (CFD) and flow visualization [5]. The miniaturized device includes a rotating impeller and a vaned-diffuser in a 7 mm axial hydraulic diameter. As seen in Figure 1, the hydrodynamic characteristics suitable for a right-VAD (RVAD) may also be suitable for pediatric patients. Currently, the only approved device is placed extracorporeal due to size constraints in the intended population [1]. This report shows results of computational simulations for anatomic fit and fluid flow studies of our device geometry in pediatric patients.