心阻抗检测及其信号分析方法研究

发布时间：2018-11-19 17:53

【摘要】：随着社会的快速发展、生活节奏生活方式的改变、人口老龄化现象的加剧，心血管疾病成为人类健康的最大威胁。如今，心血管类疾病严重影响了人们的生活质量，面对心血管疾病高发的情况，全面评价心功能、对心血管疾病做出前瞻性预警有着十分重要的现实意义。心阻抗法（Impedance Cardiogram, ICG）是一种评价心血管功能的无创性方法，心阻抗信号作为一项心脏功能评估参数，它从血流动力学方面评价心功能，对心血管疾病诊查具有重要的研究意义和临床价值。但是心阻抗信号微弱，易受呼吸等干扰，制约了该技术的临床应用。本文基于心阻抗信号的特点，提出了一种心阻抗和心电信号同步采集和处理的方法。首先基于四电极法搭建采集心阻抗并配合同步采集心电信号的采集系统。其次对胸腔阻抗信号进行噪声和频谱分析，然后基于小波变换设计了心阻抗提取方法，从胸腔混合阻抗中提取心阻抗信号，并结合心电信号标校，获取心阻抗一阶微分信号特征点，完成心功能参数的计算。针对肺部对胸腔阻抗信号的影响，本文设计了自然呼吸、屏息状态、呼吸率10次/分、呼吸率6次/分四种呼吸状态，采集32位受试者在四种呼吸状态下的胸腔阻抗信号及同步心电信号，总计256组数据。结果表明胸腔阻抗信号完全符合实验方案的设定，验证了信号采集方法的可靠性；心功能参数处于正常范围内，验证了心阻抗信号提取、特征点提取算法的准确性。本研究验证了该系统用于准确、客观、全面地分析心功能的可行性，也为利用该系统进行进一步样本扩大实验和研究奠定基础。
[Abstract]:With the rapid development of society, the change of life rhythm life style and the aggravation of population aging, cardiovascular disease has become the biggest threat to human health. Nowadays, cardiovascular diseases seriously affect people's quality of life. In the face of high incidence of cardiovascular disease, comprehensive evaluation of cardiac function, cardiovascular disease to make a forward-looking warning of cardiovascular disease has a very important practical significance. Cardiac impedance method (Impedance Cardiogram, ICG) is a noninvasive method for evaluating cardiovascular function. As a parameter of cardiac function evaluation, cardiac impedance signal can be used to evaluate cardiac function in terms of hemodynamics. It is of great significance and clinical value for the diagnosis and examination of cardiovascular diseases. However, the clinical application of this technique is restricted by weak impedance signal and easily disturbed by respiration. Based on the characteristics of impedance signal, a method of synchronous acquisition and processing of cardiac impedance and ECG signal is presented in this paper. Firstly, based on the four-electrode method, the acquisition system of the impedance of the heart and the synchronous acquisition of ECG signal is built. Secondly, the noise and spectrum of the thoracic impedance signal are analyzed, and then the method of heart impedance extraction is designed based on wavelet transform. The impedance signal is extracted from the mixed impedance of the thoracic cavity, and the ECG signal is calibrated. The characteristic points of the first order differential signal of cardiac impedance were obtained and the cardiac function parameters were calculated. Aiming at the influence of lung on thoracic impedance signal, the author designed the natural breathing, holding breath, breathing rate 10 times per minute, breathing rate 6 times per minute, four breathing states. A total of 256 sets of thoracic impedance signals and synchronous ECG signals were collected from 32 subjects in four breathing states. The results show that the pleural impedance signal is completely in accordance with the experimental scheme, and the reliability of the signal acquisition method is verified, and the cardiac function parameters are within the normal range, which verifies the accuracy of the heart impedance signal extraction and the feature point extraction algorithm. This study verifies the feasibility of the system for accurate, objective and comprehensive analysis of cardiac function, and lays a foundation for further sample expansion and research using the system.
【学位授予单位】：沈阳工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R318.04

【参考文献】