Hydrodynamics Of The Mechanical Heart Valve Prostheses

The testing of the hydrodynamic characteristics of prosthetic heart valves is the most important phase in which the valves was designed, developed and used in clinic. The performance of the prosthetic heart valves is not based on the design, material and manufacture of itself, but was affected by the characteristic of the pulsatile duplicator.This study aimed to assess the hydrodynamic function of the Jiuling bileaflet heart valve prostheses, and discuss the affecting factors on the testing results.The pulsatile circulatory system was made for testing and estimating newly Jiuling bileaflet heart prostheses. The experiment was carried out in accordance with the requirements recommended by the ISO 5840-96 (E) and GB 12279-90 for testing of prosthetic heart valves.The pulsatile duplicator has a good design, simplified structure. The working procedure of the system was easily standardized. The rig used a DC-motor controlled system can produce a physiological flow waveform through the valve.Jiuling valves have been tested in a pulsatile flow simulator in the aortic position. The testing condition were set at the cardiac output of 2.0, 3.0, 4.0, and 5.0 L/min and a constant pulsatile frequency of 75 beats/min, or at the pulsatile frequency of 55, 75, and 100 beats/min and a constant cardiac output. The mean pressure differences, leakage volumes and closing volumes across each valve, and the effective orifice areas have been analyzed. The testing condition was changed for canvassing factors associated with the performances of the heart valve prosthesis. The motion of closing and opening of the...