Non-invasive Central Aortic Pressure Monitoring System Based On Two Peripheral Pulse Waves

Cardiovascular disease has become the number one killer of human health.The central aortic pulse pressure wave has its unique and irreplaceable significance in predicting and evaluating cardiovascular disease.However,due to the special physiological location of aorta,how to measure center aortic pressure in clinical has always been a problem to people.The accuracy of invasive detection method is high,but it can bring patients pain and risk,and is difficult and expensive.On the contrary,the accuracy and degree of individualization of current noninvasive method is not satisfactory.Aiming at this situation,a noninvasive monitoring system of center aortic pressure based on two peripheral arterial pulse waves was designed in this thesis.The system which was based on the blind identification technology and the embedded electronic technology measures the peripheral arterial blood pressure and pulse waves from two different ways by using cuffs.This thesis implemented the noninvasive and individual monitoring of center aortic pressure,provided new ideas for the research and development of central aortic pressure noninvasive measuring device.The thesis first discussed the background and significance of this research,introduced domestic and foreign research situation of noninvasive detection of center aortic pressure,given the contrast analysis of center aortic pressure measurement products in the current market.Then the basic theory and modeling on the cardiovascular system was introduced.In the thesis,the SIMO blind system identification theory and the principle of Cross-Relation algorithm were expounded,provided a theoretical basis for the application of blind identification algorithm in the cardiovascular system.The thesis took advantage of the embedded hardware and software collaborative design method,deeply analyzed the system's functional requirements,and determined the system structure and implementation platform.Then,around the demand of the system,the thesis made a detailed introduction of the design and implementation process of the two subsystems respectively.First,the circuit design process of the peripheral blood pressure measurement and the two-way pulse wave acquisition subsystem and variable amplitude coefficient blood pressure measurement method based on peak fitting were discussed.Then the thesis discussed the design of the drive program of center aortic pressure reconstruction subsystem based on ARM,made detailed instructions of embedded implementation of blind identification Cross-Relation algorithm.In the process of design and implementation,by means of mutual adjustment and cooperation of the hardware and software,by means of system integration and debugging,the thesis completed the overall implementation of the system.Comprehensive test of the center aortic pressure noninvasive monitoring system was conducted by means of the experiment.System accuracy of blood pressure measurement and the feasibility of the reconstruction of center aortic pressure function were confirmed.Finally,the shortcomings of the system were analyzed.Further tests and improvements need to be done to optimize the equipment.