Pierce-Donachy pediatric VAD: Progress in development

Background. Despite the successful use of ventricular assist devices in adults over the past 15 years, relatively little has been done to develop similar devices for pediatric patients. Consequently, no such device is currently available. A review of clinical data suggests that the majority of patients in need of a pediatric ventricular assist device, either for postcardiotomy cardiogenic shock or as a bridge to cardiac transplantation, are neonates weighing 3 to 5 kg. Attempts to ''scale down'' an adult blood pump to make an appropriate device for these patients have been difficult due to the lack of sufficiently small, commercially available valves and the tendency for thrombus to develop in these small pumps. Methods. We report on progress in the development of the Pierce-Donachy pediatric ventricular assist device, which incorporates 10-mm-diameter bileaflet valve prototypes. Particle image velocimetry is used to quantify the velocity field inside the pump. Results and Conclusions. Particle image velocimetry velocity maps demonstrate the complexity of the flow patterns in these pumps and suggest that improved flow patterns may result from the use of valves with improved hemodynamic performance. Animal tests to determine whether improved flow patterns and better ''washing'' of the pump's blood-contacting surfaces will reduce thrombus formation are underway.