CORRELATION OF RADIONUCLIDE AND OPTICAL TRACER ASSESSMENTS OF FLUID-FLOW IN ARTIFICIAL VENTRICLES

Characterization of Bow properties for an artificial ventricle may aid development of designs to minimize thrombosis. Techniques for determi ning two such Bow properties, viz ventricular clearance rate and eject ion fraction, are compared and validated here for polyurethane and sil icone rubber ventricles operated in a mock circulatory loop at various stroke volumes and pulse rates. Ventricular clearance rates were meas ured both by clinical radionuclide tracer techniques and by an optical tracer method. Ejection fractions were measured by radionuclide imagi ng and validated by direct measurements of Bow rate and ventricular vo lume. Results from the two methods for ventricular clearance are in cl ose agreement. The optical tracer method is superior in spatial resolu tion, convenience and economy, but the radionuclide tracer method for ejection fraction gives excellent agreement with the absolute measurem ents.