呼吸与心跳运动干扰下的消融导管定位信号仿真分析及试验研究

发布时间：2018-05-23 12:34

本文选题：导管定位 + 包络解调　；参考：《郑州大学》2012年硕士论文

【摘要】：研究目的：研究一种消融导管定位信号处理方法,消除呼吸与心跳干扰,获得导管的位置信息。研究方法：首先根据定位原理研究了呼吸与心跳运动对于导管定位的影响,据此提出受到呼吸与心跳运动干扰的导管定位信号数学模型及其信号处理方法。采用了软件仿真分析结合硬件实验的研究路线,分别提出了两种信号处理方案。软件仿真分析采用Matlab数学软件来模拟定位信号及其信号处理过程,然后设计出相应的硬件电路来实现信号处理。在硬件设计方面采用模块化设计思想,按照EDA仿真、面包板实验、焊接电路板实验三步走的循序渐进的设计方法进行设计。实施体外胸腔电场模拟实验,检验硬件电路的稳定性和可靠性。为了获得最接近于人体的胸腔环境,课题组先后开展了二期动物实验,通过两期动物实验来验证所提出的定位信号数学模型与定位信号处理方案是否正确。研究结果：1、将受到干扰的定位信号看作是呼吸与心跳信号对于电场激励信号调幅的结果,调幅信号包络的中值就是导管在体内相对于体表电极的位置信息,这就是本研究提出的定位信号数学模型。2、提出了一种新的获取导管空间位置信息的方法：先将导管采集到的定位信号经过一个带通滤波器后变为某一个电场方向的定位信号,之后提取出定位信号包络线,然后再取其中值,这个中值就是导管电极在某一电场方向上相对于体表电极的位置信息。3、软件仿真部分采用了Hilbert变换法、平方检波法、极值曲线拟合法三种包络解调方法完成包络提取；采用低通滤波、median函数两种中值提取方法完成中值提取。4、硬件方面,带通滤波模块采用三级联DABP结构实现,包络解调模块采用模拟乘法器来完成,中值提取模块采用3阶MFB结构来实现。各个模块通过EDA仿真、面包板实验、焊接板实验三重测试均达到了比较理想的效果。5、通过体外胸腔电场模拟实验验证了本研究提出的定位信号数学模型以及定位信号处理方法是正确的,硬件电路在实际工作中稳定可靠；通过动物实验进一步证明了导管在活体生物体内的定位信号与我们所提出的模型是一致的,而且定位信号处理方案也是正确可行的。研究结论：通过软件仿真分析、硬件实验、模拟胸腔电场实验和动物实验等循序渐进的研究,实验结果验证了本研究提出的定位信号数学模型及其信号处理方案是正确的,能够消除定位信号中的呼吸与心跳干扰而得到正确的导管位置信息,可以作为进一步研究的理论基础。
[Abstract]:Objective: to study a method of ablation catheter location signal processing to eliminate respiratory and heartbeat interference and obtain catheter location information. Methods: firstly, according to the principle of location, the influence of respiration and heartbeat motion on catheter location was studied, and the mathematical model of catheter location signal and its signal processing method were put forward, which were interfered by breathing and heartbeat motion. Two kinds of signal processing schemes are proposed by software simulation and hardware experiment. Matlab is used to simulate the positioning signal and its signal processing process, and the corresponding hardware circuit is designed to realize the signal processing. In the aspect of hardware design, the modular design idea is adopted. According to the three-step design method of EDA simulation, bread board experiment and welding circuit board experiment, the design is carried out step by step. The external thoracic electric field simulation experiment was carried out to test the stability and reliability of the hardware circuit. In order to obtain the closest thoracic environment to the human body, the second phase animal experiment was carried out, and the mathematical model of the localization signal and the processing scheme of the localization signal were verified by the two-phase animal experiment. The result of the study: 1, the disturbed location signal is regarded as the result of the amplitude modulation of the respiratory and heartbeat signals to the electric field excitation signal. The median value of the amplitude modulation signal envelope is the position information of the catheter relative to the body surface electrode in the body. This is the mathematical model of location signal proposed in this study. A new method to obtain the location information of the catheter is proposed: firstly, the location signal collected by the catheter passes through a band-pass filter and then becomes the location signal in a certain electric field direction. Then the envelope of the location signal is extracted, and then the value is obtained. The median value is the position information of the catheter electrode relative to the body surface electrode in a certain electric field direction. The software simulation part uses the Hilbert transform method and the square detection method. Three envelope demodulation methods are used to extract the envelope, the median filter median function is used to extract the median value. 4. In the hardware aspect, the bandpass filter module is implemented with the three-level DABP structure. The envelope demodulation module is accomplished by analog multiplier, and the median extraction module is implemented by 3 order MFB structure. Each module through EDA simulation, bread board experiment, The triple test of welding plate has achieved the ideal effect. The mathematical model of the localization signal and the method of processing the positioning signal are proved to be correct by the external thoracic electric field simulation experiment. The hardware circuit is stable and reliable in practical work, and it is further proved by animal experiments that the localization signal of the catheter in vivo is consistent with the model proposed by us, and that the localization signal processing scheme is also correct and feasible. Conclusion: through software simulation analysis, hardware experiment, chest electric field simulation experiment and animal experiment, the experimental results show that the mathematical model and the signal processing scheme proposed in this study are correct. It can be used as the theoretical basis for further research, which can eliminate the interference of respiration and heartbeat in the location signal and obtain the correct location information of the catheter.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R318.6;TH776

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