Approaching comparability and results of pulsatile flow in vitro testing of prosthetic heart valves

The testing of prosthetic heart valves under pulsatile conditions is still a subject for debate among researchers and competent standardization bodies. The laboratory of Biomedical Engineering, of the Istituto Superiore di Sanità in Rome, has reproduced the current inter-laboratory situation with several test apparatuses, focusing on the definition of significant measurement parameters and procedures to obtain reasonably comparable data. The laboratory is also equipped with a Laser Doppler Anemometer (LDA) and a High-Speed Cinematographic system (HSC). A 29 mm tilting disc valve model, was mounted in the aortic position. Under tightly controlled system conditions the analyses performed on two pulse duplicators (PDs) may be deemed consistent for the valve model tested. Useful results, on the same valve specimen, are reported concerning velocity profiles and turbulent shear stress values (TSS). Furthermore valve motion on the Sheffield PD was monitored during the closing phase, and related cinematic data reported. The applied methodologies can provide relevant data to support surgeon decision making.