A High-definition Recording Method of Electrocardiogram / 中国医疗器械杂志

In order to improve the clarity of ECG waveforms and the anti-interference ability of ECG acquisition under abnormal conditions, this study proposes a high-definition ECG recording method based on superimposed averaging algorithm. The results show that the proposed method can more clearly reflect the details of the ECG. Meanwhile, it has a significant inhibitory effect on EMG interference. As a result, the proposed method has a positive significance for improving the anti-interference ability of ECG equipment.

Efficient QRS complex detection algorithm based on Fast Fourier Transform

An ECG signal, generally filled with noise, when de-noised, enables a physician to effectively determine and predict the condition and health of the heart. This paper aims to address the issue of denoising a noisy ECG signal using the Fast Fourier Transform based bandpass filter. Multi-stage adaptive peak detection is then applied to identify the R-peak in the QRS complex of the ECG signal. The result of test simulations using the MIT/BIH Arrhythmia database shows high sensitivity and positive predictivity (PP) of 99.98 and 99.96% respectively, confirming the accuracy and reliability of proposed algorithm for detecting R-peaks in the ECG signal.

The research of sleep staging based on single-lead electrocardiogram and deep neural network

The polysomnogram (PSG) analysis is considered the golden standard for sleep staging under the clinical environment. The electroencephalogram (EEG) signal is the most important signal for classification of sleep stages. However, in-vivo signal recording and analysis of EEG signal presents us with a few technical challenges. Electrocardiogram signals on the other hand, are easier to record, and can provide an attractive alternative for home sleep monitoring. In this paper we describe a method based on deep neural network (DNN), which can be used for the classification of the sleep stages into Wake (W), rapid-eye-movement (REM) and non-rapid-eye-movement (NREM) sleep stage. We apply the sleep stage stacked autoencoder to constitute a 4-layer DNN model. In order to test the accuracy of our method, eighteen PSGs from the MIT-BIH Polysomnographic Database were used. A total of 11 features were extracted from each electrocardiogram recording The experimental design employs cross-validation across subjects, ensuring the independence of the training and the test data. We obtained an accuracy of 77% and a Cohen's kappa coefficient of about 0.56 for the classification of Wake, REM and NREM.

Electrocardiogram (ECG) patterns of left anterior fascicular block and conduction impairment in ventricular myocardium: a whole-heart model-based simulation study / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Left anterior fascicular block (LAFB) is a heart disease identifiable from an abnormal electrocardiogram (ECG). It has been reported that LAFB is associated with an increased risk of heart failure. Non-specific intraventricular conduction delay due to the lesions of the conduction bundles and slow cell to cell conduction has also been considered as another cause of heart failure. Since the location and mechanism of conduction delay have notable variability between individual patients, we hypothesized that the impaired conduction in the ventricular myocardium may lead to abnormal ECGs similar to LAFB ECG patterns. To test this hypothesis, based on a computer model with a three dimensional whole-heart anatomical structure, we simulated the cardiac exciting sequence map and 12-lead ECG caused by the block in the left anterior fascicle and by the slowed conduction velocity in the ventricular myocardium. The simulation results showed that the typical LAFB ECG patterns can also be observed from cases with slowed conduction velocity in the ventricular myocardium. The main differences were the duration of QRS and wave amplitude. In conclusion, our simulations provide a promising starting point to further investigate the underlying mechanism of heart failure with LAFB, which would provide a potential reference for LAFB diagnosis.

Effect of intensified electrocardiogram identification by using spectrogram for the enhancing of monitoring and nursing capacity / 中国医学装备

Objective:To explore the effect of intensified electrocardiogram (ECG) identification by using spectrogram for the monitoring and nursing ability of nurses who worked in department of cardiology.Methods: Monitoring and nursing capacity of 120 nurses of cardiology who had been trained on the intensified ECG identification by using spectrogram were researched by retrospective analysis. The 120 nurses were divided into control group (60 cases) and intervention group (60 cases) as the random number table. The nurses of control group only received routine training of ECG identification, while the nurses of intervention group received the training of using spectrogram for ECG identification on basic routine training of control group. A series of indicators, including the scores of ECG comprehensive application ability, identification ability of abnormal electrocardiogram, and the number of the identified abnormal malignance ECG and successfully treated patients, between the two groups were compared and analyzed.Results: After the training, the scores of basic theory, abilities of description and recording, and analysis ability in field operation of the intervention group were significantly higher than those of the control group, respectively (t=11.896,t=8.596,t=8.283,P<0.05). The identified ability including room speed, atrial flutter, ventricular flutter and other abnormal ECG of intervention group were significantly better than these of control group, respectively (x2=18.836,x2=17.698,x2=16.773,P<0.05). Besides, the discovery rate of abnormal malignance ECG (73.3%) and the successful rate of treatment (100.0%)of intervention group were significantly higher than that (31.7% and 81.7%) of control group, respectively (x2=19.184,x2=10.484,P<0.05). Conclusion:The training of intensified ECG identification by using spectrogram for nurse of cardiology can effectively enhance the capacities of identification for ECG and comprehensive application for nurses, and can faster confirm the situation of patient, and can contribute to achieve precision diagnosis for doctors.

A study of cardiovascular involvement in Hypothyroidism

Background: Cardiac abnormalities associated with hypothyroidism attracted great deal of investigational effort. There are only few studies done in our country to asses CVS parameters in hypothyroid patients. Hypothyroidism is known to cause reversible cardiac dysfunction in humans. Aim: This study was aimed at studying the cardiovascular involvement in hypothyroidism. Materials and methods: The data for this study was collected from 40 hypothyroid patients by clinical examination and by performing ECG and Echocardiogram who came to Malla Reddy Medical College and Hospital, Hyderabad which included both outpatients and inpatients. Results: On systemic examination, diminished heart sound was found in 25 % patients. Lipid analysis showed increase of TOT.CHOL, LDL, VLDL, TGL and decrease of HDL. Normal ECG was found in 30% of patients, Bradycardia was most common finding seen in 16 patients counting for 40%. Low voltage complexes were seen in 35% patients. Echo findings were normal in 32.5% cases. Pericardial effusion was next common finding seen in 11 cases accounting to 27.5%. Diastolic dysfunction was seen in 27.5%, majority of them being mild dysfunction. No cases were found to have severe diastolic dysfunction. IVS thickness was found only in 2 cases. Conclusion: Among 40 new cases of hypothyroidism, pericardial effusion was found in 27.5% patients. Diastolic dysfunction was seen in 27.5 % patients. All the patients diagnosed with hypothyroidism are to be screened for pericardial effusion and other cardiac complications

Effect of lead aVR on recent prognosis in patients with non -ST -elevation acutecoronary syndrome / 中国基层医药

Objective To investigate the effect of lead aVR on recent prognosis in patients with non -ST -elevation acutecoronary syndrome(NSTE -ACS).Methods 195 patients with NSTE -ACS were divided into ST segment elevation in lead aVR group(n =54 cases)and non -ST segment elevation in lead aVR group(n =141 ) according to ST segment elevation in lead on admission;clinical data,laboratory index and coronary artery lesion were recorded,and major adverse cardiac (MACE)in hospitalization time were also recorded.Results Compared with non -ST segment elevation in the lead aVR group,the heart rate of ST segment elevation in the lead aVR group was faster[(85.4 ±12.0)beats per minute vs.(79.3 ±13.2)beats per minute,t =2.959,P <0.05],systolic blood pressure and diastolic blood pressure were higher[(145.0 ±20.3)mmHg vs.(136.0 ±19.4)mmHg,t =2.874,P <0.05];NT -proBNP[(743.9 ±125.8)pg/mL vs.(416.4 ±95.3)pg/mL,t =19.625,P <0.05],cTnI[(3.4 ± 1.0)ng/mL vs.(1.2 ±0.4)ng/mL,t =21.994,P <0.05],CK -MB[(31.5 ±9.8)ng/mL vs.(19.8 ±6.5)ng/mL, t =9.682,P <0.05]were higher (P <0.05);LVEF were lower[(50.1 ±5.2)% vs.(53.8 ±5.7)%,t =4.153, P <0.05];the rate and amplitude of low ST segment in outside lead aVR also was higher[(9.5 ±3.8)mm vs. (7.4 ±2.8)mm,t =4.224,P <0.05];the rate of left main and three -vessel disease in ST segment elevation in lead aVR group were higher (P <0.05).Compared with non -MECE group,proportion of ST segment elevation in lead AVR on admission was higher (P <0.05).Logistic regression analysis showed that heart rate(OR =1.472),NT -proBNP(OR =1.732),cTnI(OR =1.893),left main coronary artery(OR =2.478)and three -vessel disease (OR =2.310)were risk for ST segment elevation in lead AVR(P <0.05).Logistic regression analysis also showed that ST segment elevation in lead AVR were risk for MACE(OR =1.474).Conclusion ST segment elevation in lead AVR has close relationship with large area of myocardial ischemia,and patients prognosis is poorer,which may be independ-ent risk factor for the recent outcomes of patients with NSTE -ACS.Early record of the change in the case of aVR lead ECG ST segment NSTE -ACS patients is of important value in evaluation of the condition and prognosis.

Transvenous Permanent Pacemaker Implantation in 14 Month Old baby with Congenital Complete Heart Block.

Congenital Complete Heart Block in utero has been diagnosed more frequently with the clinical use of fetal echocardiography. The fetus with complete heart block may remain asymptomatic or develop congestive heart failure. Pacemaker therapy in children involves unique issues regarding patient size, growth, development and possible presence of congenital heart disease. Historically, epicardial pacing was more common in children. As technology has improved, generators and leads have become smaller and more advanced, allowing transvenous pacing system in children. Pacemaker therapy is even technically feasible in infants and neonates. We present a 14mth old baby of just 7.5kg who presented to us with Adams Stokes and subtle signs of congestive heart failure that after stabilization was implanted a transvenous MRI compatible permanent pacemaker (VVIR).

Análise comparativa de desempenho das transformadas Wavelet e Hilbert na detecção do QRS em ECG / Performance comparison analysis of Wavelet and Hilbert transforms for QRS detection in ECG

O processo de detecção do complexo QRS é o primeiro passo de um processo de extração de parâmetros do sinal eletrocardiograma (ECG) em sistemas de auxílio ao diagnóstico médico. O presente trabalho apresenta resultados detalhados de comparação da aplicação de duas transformadas matemáticas, Wavelet e Hilbert, em um algoritmo de detecção de QRS em termos de taxas de detecções corretas (sensibilidade e preditividade positiva) e de uma medida de frequência de recorrência a processos de filtragem (pré-processamento). Uma abordagem inovadora é implementada, na qual as rotinas de filtragem são inseridas dentro do estágio de decisão, ou seja, é realizada a supressão da etapa de pré-processamento. As transformadas são aplicadas no algoritmo, que é baseado em um limiar adaptativo, com o objetivo de realçar, apenas quando necessário, os picos (pontos fiduciais)do QRS. Em uma primeira abordagem, apenas a transformada Wavelet é utilizada neste realce e, numa segunda abordagem, a transformada de Hilbert é inserida em série à aplicação da Wavelet em dois possíveis arranjos. São realizados experimentos dos algoritmos sobre os exames da base de dados Arrhythmia Database, pertencente ao conjunto de bases de dados do MIT-BIH. É composta por 48 gravações de ECG com duração de trinta minutos, amostrados a uma frequência de 360 Hz com resolução de 4,88 μV sobre uma faixa de variação de 10 mV. Ao todo, contabilizam-se 109.662 complexos QRS. Taxas de 98,85% de sensibilidade e 95,10% de preditividade positiva são obtidas com a aplicação exclusiva da transformada Wavelet, enquanto que 98,89% de sensibilidade e 98,52% de preditividade positiva são obtidas com aaplicação em série das transformadas Wavelet e de Hilbert.

The process of QRS detection is the first stage of a greater process: the feature extraction in the electrocardiogram (ECG). This work presents detailed results on the performance of two mathematical transforms, Hilbert and Wavelet, which are applied in QRS detection. The evaluation parameters are the detection rates and a measure of frequency of recurrence to filtering processes. An innovative approach is implemented: the filtering routines are inserted in the decision stage, i.e. the preprocessing stage is removed. The algorithm is based on adaptive threshold technique and the two transforms are applied in order to emphasize, only when necessary, the QRS fiducial points. In a first approach, only the Wavelet transform is applied, and in a second approach, the Hilbert transform is inserted before the Wavelet transform or after it. We evaluate these approaches on the well-known MIT-BIH Arrhythmia Database. It contains 48 half-hour recordings of annotated ECG with a sampling rate of 360 Hz and 4.88 μV resolution over a 10 mV range, totalizing 109,662 QRS complexes. Sensitivity rates of 98.85% and 98.89% are respectively attained when the Wavelet transform is applied in the filtering processes and both Hilbert and Wavelet transforms are applied. Predictability rates of 95.10% and 98.52% are also attained respectively using Wavelet transform and the simultaneous application of Hilbert and Wavelet transforms in the filtering processes.

Study on Regulation of ECG Cycle Fluctuation / 航天医学与医学工程

Objective To investigate the regulation of fluctuation of beat to beat cardiac cycle.Methods A cardio-electric cycle consists of cardio-electric activity called P-T interval and cardio-electric resting TP segment,P-R interval and Q-T interval constitute P-T interval.The cardiac cycles fluctuate along with the time span fluctuation of sub waves and segments.This paper firstly extracted sub waves and segments based on signal processing methods,then discussed the contribution ratio of all waves and segments toward cardiac cycle fluctuation according to statistics.Results Experimental results indicated that the cardiac cycle fluctuation was mainly consistent with the change of TP segment.The P-T interval varied consistently with P-R interval foremost.Conclusion It is revealed that rule of cardiac cycle fluctuation is very useful for further research to figure out the cardiac function and mechanism.

Applications designed for a tele-monitoring electrocardiogram system / 医疗卫生装备

This article introduces a new applications which is used in the central electrocardiogram monitoring system of a tele-monitoring system for electrocardiogram transmitted by telephone.The applications is composed of the components of database,real-time monitoring and signal processing.The paper is mainly about digital wave filter used to process real-time collected signals and the algorithm to measure the interval between R-R electrocardiograms.

effects of various degrees of coronary stenosis on Lyapunov exponents of ECG and R-R interval time series / 中国医学物理学杂志

Purpose:It has been shown that the heart is a chaotic oscillator. So it is appropriiate to use the Lyapunov exponent, an important parameter to identify the nature of non-linear dynamical systems, for identifying the state of human heart. Methods:Preliminary results are obtained in this paper using Wolf's algorithm for 8 normal and 107 abnormal ECG recordings. Results:Significant differences are found between the Lyapunov exponents of normal ECG and ECG with obvious coronary stenosis (OCS), but there is no significant difference between the Lyapunov exponents of normal ECG and ECG with mild coronary stenosis (MCS);Significant differences are also found between the Lyapunov exponents of R-R interval series of normal ECG、ECG with MCS and ECG with OCS. Conclusions:It is apparent that the R-R interval series can give us more messages about human heart, and the Lyapunov exponents of ECG and R-R interval series are the appropriate parameters for the identification of the physiological states of human heart. It is possible to use Lyapunov exponent for early diagnosis of Coronary Heart Disease.

Practical electrocardiographic interpretation

In summary, electrocardiographic interpretation is anchored on the objective reading of the ECG without the advantage of seeing and/or knowing the patient when the electrocardiographer is isolated in the heart station. When the electrocardiographer is the attending physician, the advantage of knowing the patient may create a favorable bias in the interpretation, leading to a clearer understanding of the ECG and correct diagnosisSeparating the normal from the abnormal tracing is of primary concern to any electrocardiographer. Sorting out the types of abnormalities is the second step. Done this way, the ECG becomes an important diagnostic tool in providing excellent cardiac care delivery.

Electrocardiography: II. Common electrocardiographic findings and the diseases associated with them: diagnostic guidelines for general practice

A resting ECG is not and never has been an absolute tool in establishing physical fitness. Note that no single ECG finding is associated with any single clinical entity. Each ECG finding must be correlated clinically, and further laboratory documentation is sometimes necessary so that a fair and justifiable clinical decision can be made. A TECG is additionally requested to determine functional capability of the cardiopulmonary system, while a CSG is additionally requested to confirm and document anatomic patterns. An ambulatory Holter ECG is additionally requested when documenting arrhythmias in relation to daily routine activities, or to document ischemia when prevailing conditions do not allow performance of a TECG. (Conclusion)

The heart function change in patients with acute cerebral hemorrhage / 重庆医科大学学报

Objective:To get the message ofthe cardiac dysfunction arises from the cerebral hemorrhage in CH patients by investigate the relationship among the Electrocardiographic abnormalities、the hemorrhagic location、the cerebral lesion degree and the outcome.Methods:Analysis the ECG of the 304 acute hemorrhagic stroke patients who made the final diagnosis by CT,without the history of heart disease.Results:There are evident change of the ECG in acute hemorrhagic stroke patients,the total incidence rate reach up to 67.1%(204/304),and these change keep close tothe cerebral lesion location that different fromthe relation between themand the cerebral lesion degree and link with the prognosis with the cerebral lesion degree,P