Abstract
A mechanical circulatory system which can simulate the hemodynaic functioning as well as cardiac valve functioning in real world conditions is currently under development. This system consists of a cone-shaped left ventricle (LV) and leaflet valves, both of which were made from segmented polyurethane. A globeshaped left atrium (LA) and a U-shaped aorta (Ao) were made of silicone. Supplementary compliance tanks and servo-controlled valves were incorporated in the circulatory model. Then, natural aortic waveforms including peaking and steepening phenomena could be obtained in the model. After the modification of the software of the pneumatially-operated heart driver, the artificial atrium could be slightly collapsed prior to the contraction of the ventricle. Consequently, similar behavior of the valve implanted at the mitral position could be simulated. After several trials to simulate cardiac failure in the model, it was noted that the Emax curve obtained from the current model was very similar to that of the natural heart. As the Emax curve simulated by the new system gave a better understanding of clinical hemodynamic data, the true valve function can be deferentiated from the cardiac function findings obtained through the simulation data on heart valves. This ability to simulate natural cardiac fanctioning is the main advantage this system has over other simulation systems, including mathematical or electrical models.
