| Nowadays, with the increasing number of heart disease suffers, heart trouble has become one of the main diseases that threaten human's health in the modern society. More seriously, traditional therapy of organ transplants is far from meeting the demands of the patients suffering from the most serious congestive heart failure, because of the shortage of donor organs. Therefore, total artificial heart (TAH), especially the electric total artificial heart (ETAH) of second generation, which has the completely implantable characteristics, has gained concerns of international researchers. For example, since the beginning of the 1990s, the National Institutes of Health (NIH) has given special support to the research on the system (ETAH), and some companies started to carry out clinical trials in 2004. In August 2006, FDA first approved to allow the 4,000 "AbioCor" artificial hearts for heart transplantation annually, which are produced by Abiomed Company in Denver City of Massachusetts of U.S.A. . However, in our country, apart from a few scattered studies of mechanical circulatory support systems, such research has not been reported in China yet. Moreover, prior to the animal experiments on TAH, it is necessary to test the overall system performance of the TAH prototype by the use of Total Artificial Heart testing system. So far, there are only a few reports on the foreign TAH testing systems, while the domestic TAH testing system and the related investigation have not been reported.This project aims to design and implement a TAH testing system applicable to the electric reciprocating plate-pushing TAH. In the thesis, a mathematical model of the TAH testing system, the modeling method, the hardware structures of the data acquisition system and the data collection programs were described in detail. Such an investigation has not been reported in China before and belongs to the same technical generation as the existing research system abroad.Its major features are as follow: 1) Bases on elastic chamber model, we have showed a new model which is an overall characteristics with the lumped parameter model of the human blood circulation system. The resistances and capacitances in the original two components model are replaced by the elastic chambers and damp valves with the corresponding parameters, and the new model is built up in the way similar to that of the original two components model. The model has the following features: the blood circulatory system is treated as an independent system in the model; the interaction between the internal organs and the overall responses of circulatory system is emphasized; the descriptions of the characteristics of the various components are simplified so that fewer parameters and less calculation are required to develop the physical model with more explicit physiologic significance. In comparison with the ordinary two components model or Frank lumped parameter model that used by the resistance, capacitor modeling, this new model simulates the paths of blood flow directly. As a result, a better approximation of the true physical testing system is realized. 2) The TAH testing system, which is made of polymethyl and has the split-type structure, allows more convenient experimental observations and the easier installation, maintenance, upgrade of assistive devices and various sensors. This lays the foundation for the miniaturization and standardization of the entire system. 3) The testing system with a wide range of adjustable parameters and many kinds of methods to adjust parameters can simulate not only the normal human blood circulation system, but also human hypertension or hypotension state. Consequently, the application of the system can be expanded. 4) The combination of testing procedures and control procedures makes it possible to monitor the horizontal displacements in real time and enhance the straightforwardness and convenience of detection and monitoring of the TAH, in addition to achieve real-time detection and records of the path flow and pressureThe experimental results have proved that the system is easy to operate and the data are accurate, credible and reproducible. The present study gives a new reference for the further investigation in the TAH and related fields at home and abroad.
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