HIGH-RESOLUTION FLUORESCENT PARTICLE-TRACKING FLOW VISUALIZATION WITHIN AN INTRAVENTRICULAR AXIAL-FLOW LEFT-VENTRICULAR ASSIST DEVICE

Flow visualization is typically applied in blood pump development to b oth confirm the design expectations and identify regions that may be p redisposed to blood element deposition and trauma. Rotary pumps, in pa rticular, place high demands on the technique chosen to visualize the flow given the limited visual accessibility of the flow path and the h igh impeller speeds. Fluorescent image-tracking velocimetry currently is used at the University of Pittsburgh Medical Center to visualize fl ow accurately inside of these pumps both qualitatively and quantitativ ely. Flow patterns under steady conditions within an intraventricular axial flow, left ventricular assist pump (prototype No. 7, SUN Medical Technology Research Corporation, Nagano, Japan) were investigated usi ng this technique. The flow fields at the impeller-stator interface an d at the pump outlet were given specific attention. This allowed the a ssessment of the fluid dynamics throughout the hydrodynamic design lim its of the pump.