【作者】 陈国豪；

【导师】 林土胜；

【作者基本信息】 华南理工大学 ， 信号与信息处理， 2011， 硕士

【摘要】 心房颤动(房颤)是指心房肌纤维出现每分钟250次到500次的不协调、不规则乱颤,是最常见的心律失常疾病之一。目前由于难以有效地跟踪房颤的状态变化和治疗效果,致使房颤的诊断准确率较低,治疗的效率和效果也都不高。采集体表心电图(Electrocardiogram,ECG)是获取患者心脏状态信息最重要的方式之一。房颤患者的ECG主要表现为正常的窦性P波被紊乱的f波(即房颤信号)取代。f波的幅度、频谱和峰度等特征量可以从不同角度与程度上反映房颤的生理特征和机制,因此从ECG中提取f波成为房颤的计算机辅助诊疗中至关重要的一步。根据适用范围的不同,房颤信号的提取方法可分为多导联提取和单导联提取两类,适用于不同的临床情况。本文尝试将现代信号处理技术应用于房颤信号的提取中,希望能够提出综合性能更好的新的提取方法。本文主要的研究内容如下。提出一种可从多导联ECG中提取房颤信号的方法。该方法基于盲信号分离技术,将提取过程分为两步处理,分别采用独立成分分析和二阶盲辨识算法,不仅具有其它多导联提取方法的优点,而且提取出来的房颤信号中包含的高斯噪声成分更少。提出一种可从单导联ECG中提取房颤信号的方法。该方法基于独立成分分析和心搏相关性,对心室波的去除更加彻底,更重要的是它消除了其它单导联提取方法的固有缺陷,即易受伪迹和异位心搏的影响。通过实验检验这两种方法的可行性和有效性,并且与其它方法的提取效果进行对比,证明这两种方法的效果更优。更多还原

【Abstract】 Atrial fibrillation (AF) is one of the most common sustained arrhythmias in which the atrial fibrillate randomly 250~500 times per minute. It is hard to track the natural history of arrhythmia and its response to treatment, so the diagnostic accuracy is very low, and the effect of therapy is poor and inefficient.Acquiring electrocardiogram (ECG) is one of the most important ways to get the patient’s health condition of heart. Turbulent f wave appears in AF patient’s ECG instead of Sinus P wave. The physiological characteristic and mechanism of AF can be reflected from the amplitude, spectrum, and kurtosis of f wave. The ways to extract AF signal can be divided into two types according to different applicability: extracting AF signal from single lead ECG and from multi-lead ECG. It is intended to propose a new method of AF signal extraction in this paper, by applying modern signal processing technique.The main contributions of this thesis are as follows:Propose a method of extracting AF signal from multi-lead ECG. This method which is based on blind signal separation divides the processing into two steps using Independent Components Analysis and Second Order Blind Identification respectively. Besides the advantages that other multi-lead extraction methods have, there is less gaussian noise in the AF signal extracted by this method.Propose a method of extracting AF signal from single lead ECG. This method which is based on Independent Components Analysis and heart beat correlation can cancel ventricular signal thoroughly. What’s more, it eliminates the inherent defects of other single lead extracting methods: it is easily affected by artifact and ectopic beat.Test the feasibility and effectiveness of two methods proposed in this paper through experiment, and prove the effect of two methods is better than that of other methods.更多还原