高介神经网络用于心电信号的识别

心电图（ＥＣＧ）的自动识别用分类长期以来一直是较难解决问题，特别是当截取ＥＣＧ信号的起点不同（相当于信号发生平移）及有基线漂移（相当于信号发生旋转）时，在不作预处理情况下要求仍能正确识别及分类，即要求识别过程具有平移不变性和旋转不变性，更是困扰生物医学工程工作者的困难问题之一。作者采用高阶神经网络（二阶）、对五类（正常类，高Ｒ波类、高Ｔ波类、Ｔ波倒置类及心律不齐类）具有平移及旋转的ＥＣＧ信号进行分     

ECG自动分析技术的发展

本文对ＥＣＧ主要特征参数的自动分析技术进行了综述。在ＱＲＳ波检测中，介绍了基本信号处理的方法、基于图象识别的方法以及最近的子波变换、神经网络方法。同时介绍了Ｐ波、Ｔ波和ＳＴ段检测中的主要方法与存在的问题。     

ECG自动分析技术的发展

本对ＥＣＧ主要特征参数的自动分析技术进行了综述。在ＱＲＳ波检测中，介绍了基本信号处理的方法、基于图象识别的方法以及最近的子波变换、神经网络方法。同时介绍了Ｐ波、Ｔ波和ＳＴ段检测中的主要方法与存在的问题。     

高阶神经网络用于心电信号的识别

心电图（ＥＣＧ）的自动识别及分类长期以来一直是较难解决的问题，特别是当截取ＥＣＧ信号的起点不同（相当于信号发生平移）及有基线漂移（相当于信号发生旋转）时，在不作预处理情况下要求仍能正确识别及分类，即要求识别过程具有平移不变性和旋转不变性，更是困扰生物医学工程上作者的困难问题之一。作者采用高阶神经网络（二阶），对五类（正常类、高Ｒ波类、高Ｔ波类、Ｔ波倒置类及心律不齐类）具有平移及旋转的ＥＣＧ信号进行分类识别。结果表明，本网络具有较好的分类效果。平移信号不受任何限制，可任意平移，旋转信号最大旋转幅度为原信号的２０％。本工作全部在微机上完成，而且本网还具有灵敏度高，学习时间短等特点，而有较大的临床实用价值。     

用移动平均幅值微分算法检测胎儿R波

用移动平均幅值微分算法检测胎儿Ｒ波［英］／Ｐａｒｋ　ＹＣ…／／ＩＥＥＥＴｒａｎｓＢＭＥ．－１９９２，３９（８）．－８６８胎儿ＥＣＧ信号处理问题包括从腹导ＥＣＧ信号中去除母体ＱＲＳ复合波增强胎儿ＱＲＳ复合波，检测胎儿Ｒ波计算胎儿心率。ＡＭＤＦ（ａｖｅｒ...     

心电信号数据压缩技术的发展

心电数据压缩是心电信号计算机处理技术的一个重要组成部分，ＥＣＧ压缩算法一般可分成：直接压缩法、变换压缩法和特征参量提取法。文献「１」是篇重要的ＥＣＧ压缩技术综述，归纳了ＥＣＧ压缩原理及在９０年代之前的发展状况；本则简要描述九十年代以来有关ＥＣＧ压缩算法工，主要侧重于周期压缩法，小波变换压缩法和神经网络方法。     

64例癫痫患者脑Holter动态脑电图监测报告

６４例癫痫患者脑Ｈｏｌｔｅｒ动态脑电图监测报告张翼麟，张均森，杜丽红，李志芳２４小时动态脑电监测技术（ＡＥＥＧ），应用于临床能提高癫痫疾病诊断阳性率。我院１９９３年用脑Ｈｏｌｔｅｒ实时记录２４ｈ脑电图（ＥＥＧ）检测癫痫及可疑癫痫发作共６４例，与自身的...     

使用神经网络检测心电图(ECG)“左心室劳损”

使用神经网络检测心电图（ＥＣＧ）“左心室劳损”［英］／ＢｅｖｉｎｅＢ…／／ＭｅｄＢｉｏｌＥｎｇＣｏｍｐｕｔ．－１９９３，Ｊｕｌｙ．－３４３本文研究了利用人工神经网络对ＥＣＧ的ＳＴ—Ｔ段异常的分类。我们从１０５例ＥＧＣ中选出３５６个侧导联的数据组成训练...     

心电信号数据压缩技术的发展

心电数据压缩是心电信号计算机处理技术的一个重要组成部分，ＥＣＧ压缩算法一般可分成：直接压缩法、变换压缩法和特征参量提取法。文献〔１〕是篇重要的ＥＣＧ压缩技术综述，系统地归纳了ＥＣＧ压缩原理及在９０年代之前的发展状况；本文则简要描述九十年代以来有关ＥＣＧ压缩算法的发展，主要侧重于周期压缩法、小波变换压缩法和神经网络方法。     

同步EEG—ECG检查的临床应用

癫　或拟诊癫　患者在发作时或发作间期的心电图（ＥＣＧ）异常较常见。近年来，随着检查手段的发展，同步脑电图─心电图（ＥＥＧ—ＥＣＧ）描记在临床上的应用，对癫　或拟诊癫　患者的异常ＥＣＧ的认识水平亦在不断提高。本文着重概述同步ＥＥＧ—ＥＣＧ在癫　诊治过程中的作用和重要性，主要用于以下几个方面。１ 主要表现为ＥＣＧ异常的植物神经性发作 癫　病人发作中ＥＣＧ异常明显增多。Ｓｈｐｒａｋｈ等［１］对５１例１６～３２岁经心脏超声、ＥＣＧ、动态心电图（Ｈｏｌｔｅｒ）检查后确认无任何心脏疾病的癫　患者作ＥＥＧ—ＥＣ…     

三通道动态心电记录分析系统

作者介绍中心研制的一种三通道Ｈｏｌｔｅｒ系统，用于和时间动态心电图的记录和分析。此系统在硬件线路中采用了专门的校正技术，以补偿记录器因带速不稳带来的误差，该系统的记录器功耗十分低，可以连接记录７２小时的动态心电图，系统软件内容丰富，功能完善，整个系统性能稳定可靠，具有较高的性能价格比。     

嵌入动态心电图的人体运动强度检测

目的：人体的很多生理状态与运动强度或运动能耗相关,人体运动强度的测量在许多领域都有重要的意义。在便携式动态心电图仪中增加检测和记录实时人体运动强度的功能,以一种简便的方法实现心电图以及运动强度的同步检测,能够以更加全面的数据反映心脏机能,为发现冠心病提供手段。方法：基于ARM核的STM32F103微处理器构建动态心电图仪,嵌入MMA7260Q三轴加速度计检测人体躯干的加速度。运用振动检测算法将其转化为反映实时人体运动强度的数值。该仪器可提供24 h的数据采集和存储,数据可上传至PC进行进一步分析和处理。结果：经过样机测试,实现了对人体心电信号和运动强度的同步采集、处理、存储和在LCD上显示。该方法能够有效检测人体运动强度,对不同运动强度的人体活动有明显的区分。结论：该方法进行人体运动强度检测能满足测量的实时性、客观性、准确性及可靠性的要求。具有结构简单、体积小巧、经济耐用的优点。结合动态心电图功能,可广泛应用在多种实际需求中,具有很好的应用前景。     

Clinical evaluation of a wireless ECG sensor system for arrhythmia diagnostic purposes

In a clinical study, a novel wireless electrocardiogram (ECG) recorder has been evaluated with regard to its ability to perform arrhythmia diagnostics. As the ECG recorder will detect a “non-standard” ECG signal, it has been necessary to compare those signals to “standard” ECG recording signals in order to evaluate the arrhythmia detection ability of the new system. Simultaneous recording of ECG signals from both the new wireless ECG recorder and a conventional Holter recorder was compared by two independent cardiology specialists with regard to signal quality for performing arrhythmia diagnosis. In addition, calculated R–R intervals from the two systems were correlated. A total number of 16 patients participated in the study. It can be considered that recorded ECG signals obtained from the wireless ECG system had an acceptable quality for arrhythmia diagnosis. Some of the patients used the wireless sensor while doing physical sport activities, and the quality of the recorded ECG signals made it possible to perform arrhythmia diagnostics even under such conditions. Consequently, this makes possible improvements in correlating arrhythmias to physical activities.     

Holter electrocardiogram network system to support regional medical care

To support regional medical care, the clinical laboratory of Kochi Medical School Hospital developed a Holter electrocardiogram (ECG) network system with regional hospitals. Holter ECG data are received from the regional hospitals and reports are sent back using the Internet. When Holter ECG shows recordings which need immediate attention such as ventricular tachycardia or ischemic ST changes, a medical technologist contacts the regional hospital immediately. The reports are checked and approved by a cardiologist who also gives advice to doctors concerning the treatment of patients. By using the medical facilities and personnel of the university hospital, this system provides rapid and appropriate medical care for patients in our area. Moreover, improvement in the skills and knowledge of the technologists in our hospital was achieved using the Holter ECG network system.     

异常心电图的自动分析与诊断

目的当前自动诊断系统中,专家系统不具备学习功能,神经网络系统由于"黑箱"特性缺乏可解释性,因此提出一种结合专家系统和神经网络优势的心电图自动诊断算法。方法本系统包含有特征提取模块、诊断矩阵模块和诊断推理模块等主要模块。在诊断系统的实现过程中,首先从心电信号中提取语义特征,然后结合描述语义特征与病类关系的诊断矩阵计算出该患者患每种疾病的可能性概率,最后根据阈值判断患者所患的疾病。在实验验证部分,利用系统以前没有诊断过的数据进行了测验,通过分析诊断的准确率对系统进行了验证。结果从Physio Bank数据库提取了1200条数据进行预测和结果分析,平均准确率为95.2%。结论本文提出的心电图自动诊断算法,以语义特征作为诊断依据,结合了神经网络和专家系统二者的优势,在各种病类的诊断上准确率都较高。     

Design,implementation and evaluation of amicrocomputer-based portable arrhythmia monitor

The design of a portable, battery-operated microcomputer-based monitor for ambulatory ECG recording and analysis is described. Designed for real-time cardiac arrhythmia analysis, it is suitable for use on ambulator, patients for several weeks, and is about the size and weight of a Holter recorder. The device differs from a Holter recorder in that is does not store normal complexes but recognises and alarms on significant arrhythmias. It sotres 16 s of the arrhythmic event, which it can transmit by telephone to a central receiving station for immediate appraisal by a cardiologist. The monitor uses a CMOS microcomputer and has 2kbytes of program memory and 2kbytes of data memory. The arrhythmia monitor program recognises tachycardia, bradycardia, asystole, dropped beats, and PVCs. The alarm limits are physician programmable. The performance of the monitor was evaluated with standard annotated ECG tapes provided by MIT/BIH. This device should be useful for applications such as antiarrhythmic drug studies, for pacemaker and postsurgery evaluations, and for detecting premonitory as well as life-threatening arrhythmias.     

The clinical application and limitation of electrocardiography

Electrocardiography (EGG) is one of the most useful methods for diagnosis of the heart diseases, including ischemic heart disease, cardiomegaly and arrhythmias. However, image methods such as echocardiography, CT-scan and MRI for diagnosis of heart diseases developed in the recent several years gave rise to some conflictions between the findings obtained by ECG and the imaging methods. Therefore, the diagnostic criteria of ECG had to be re-examined. The body Surface Map (MAP) with 87 leads on the body surface revealed more circumstantial electric phenomena of the heart than the standard 12-lead ECG and vectorcardiography. However, the MAP needs a lot of time for recording and diagnosis because of its many electrodes. Computer diagnosis adequately developed, and simplification and abbreviation of recording are required. Morphologic disorders of the heart can be diagnosed more adequately by imaging methods such as echocardiography and CT-scan than ECGs. However for the study of arrhythmias, ECGs including standard 12-lead, vector and Holter electrocardiographies, and MAP are almost the only methods now available. Each method of ECG has different characteristics and is widely accepted not only for clinical diagnosis but also research of arrhythmias. In the near future, noninvasive examination from the body surface to reveal a minute electric change of the heart will be expected instead of invasive examinations as His-bundle ECGs.     

Recording of ECG signals on a portable MiniDisc recorder for time and frequency domain heart rate variability analysis

Analysis of heart rate variability (HRV) is a non-invasive technique useful for investigating autonomic function in both humans and animals. It has been used for research into both behaviour and physiology. Commercial systems for human HRV analysis are expensive and may not have sufficient flexibility for appropriate analysis in animals. Some heart rate monitors have the facility to provide inter-beat interval (IBI), but verification following collection is not possible as only IBIs are recorded, and not the raw electrocardiogram (ECG) signal. Computer-based data acquisition and analysis systems such as Po-Ne-Mah and Biopac offer greater flexibility and control but have limited portability. Many laboratories and veterinary surgeons have access to ECG machines but do not have equipment to record ECG signals for further analysis. The aim of the present study was to determine whether suitable HRV data could be obtained from ECG signals recorded onto a MiniDisc (MD) and subsequently digitised and analysed using a commercial data acquisition and analysis package. ECG signals were obtained from six Thoroughbred horses by telemetry. A split BNC connecter was used to allow simultaneous digitisation of analogue output from the ECG receiver unit by a computerised data acquisition system (Po-Ne-Mah) and MiniDisc player (MZ-N710, Sony). Following recording, data were played back from the MiniDisc into the same input channel of the data acquisition system as previously used to record the direct ECG. All data were digitised at a sampling rate of 500 Hz. IBI data were analysed in both time and frequency domains and comparisons between direct recorded and MiniDisc data were made using Bland-Altman analysis. Despite some changes in ECG morphology due to loss of low frequency content (primarily below 5 Hz) following MiniDisc recording, there was minimal difference in IBI or time or frequency domain analysis between the two recording methods. The MiniDisc offers a cost-effective approach to intermediate recording of ECG signals for subsequent HRV analysis and also provides greater flexibility than use of human Holter systems.     

Clinical evaluation of ECG at the onset subjective symptoms using real-time analysis electrocardiograph (event recorder)

Examination of patient complaining of palpitation, chest pain and chest discomfort is usually performed by 12-lead electrocardiograph. However, the recording time is short and there are few opportunities to capture an ECG demonstrating conditions during subjective symptoms. To investigate the cause, we need to obtain an ECG during subjective symptoms. Thus, we frequently use a Holter ECG, which can be recorded for 24 hours. However, some patients have a low frequency of subjective symptoms, which may not appear during a 24-hour examination. We used a real-time electrocardiograph (Event Recorder CG-6106 made by Card Guard Scientific Survival Limited) as a monitor during subjective symptoms. Thereafter, ECG findings at the onset of subjective symptoms could be analyzed in 30 patients who did not have a clear cardiac disease. In this examination, arrhythmia was recorded in 25 of 30 cases. Although in these cases ECG during subjective symptoms could not be captured even when Holter examination was performed several times ECG during subjective symptoms was captured using an Event Recorder. This method using an Event Recorder is simple and convenient, moreover, is considered very useful for investigation of subjective symptoms. In the future, the use of an Event Recorder for heart-health-care in the daily life of healthy people and/or cardiac disease patient is highly anticipated.