Electrocardiogram(ECG)is a low-cost,simple,fast,and non-invasive test.It can reflect the heart’s electrical activity and provide valuable diagnostic clues about the health of the entire body.Therefore,ECG has been wi...Electrocardiogram(ECG)is a low-cost,simple,fast,and non-invasive test.It can reflect the heart’s electrical activity and provide valuable diagnostic clues about the health of the entire body.Therefore,ECG has been widely used in various biomedical applications such as arrhythmia detection,disease-specific detection,mortality prediction,and biometric recognition.In recent years,ECG-related studies have been carried out using a variety of publicly available datasets,with many differences in the datasets used,data preprocessing methods,targeted challenges,and modeling and analysis techniques.Here we systematically summarize and analyze the ECGbased automatic analysis methods and applications.Specifically,we first reviewed 22 commonly used ECG public datasets and provided an overview of data preprocessing processes.Then we described some of the most widely used applications of ECG signals and analyzed the advanced methods involved in these applications.Finally,we elucidated some of the challenges in ECG analysis and provided suggestions for further research.展开更多
Aslanger’s sign,also known as the arterial pulse tapping artifact or electromechanical association artifact,is an electrocardiographic artifact caused by arterial pulsation at the site where the limb leads of the sta...Aslanger’s sign,also known as the arterial pulse tapping artifact or electromechanical association artifact,is an electrocardiographic artifact caused by arterial pulsation at the site where the limb leads of the standard 12-lead electrocardiogram near the radial or posterior tibial arteries are positioned,particularly in hyperdynamic states.[1–8]It occurs in every cardiac cycle with a constant coupling interval between the QRS complex and artifact.This synchronization with the underlying heart rhythm makes it less likely to be recognized as an artifact compared to unsynchronized artifacts,such as those caused by limb movement and inadequate contact between the electrode and skin.[1,2,7,8]Almost all reported cases of Aslanger’s sign exhibit an unusual waveform morphology in all 12 leads except one of the standard 12-lead electrocardiogram.This sign is often confused with an electrocardiographic finding commonly observed during acute coronary events.展开更多
Electrocardiogram(ECG)signal is a measure of the heart’s electrical activity.Recently,ECG detection and classification have benefited from the use of computer-aided systems by cardiologists.The goal of this paper is ...Electrocardiogram(ECG)signal is a measure of the heart’s electrical activity.Recently,ECG detection and classification have benefited from the use of computer-aided systems by cardiologists.The goal of this paper is to improve the accuracy of ECG classification by combining the Dipper Throated Optimization(DTO)and Differential Evolution Algorithm(DEA)into a unified algorithm to optimize the hyperparameters of neural network(NN)for boosting the ECG classification accuracy.In addition,we proposed a new feature selection method for selecting the significant feature that can improve the overall performance.To prove the superiority of the proposed approach,several experimentswere conducted to compare the results achieved by the proposed approach and other competing approaches.Moreover,statistical analysis is performed to study the significance and stability of the proposed approach using Wilcoxon and ANOVA tests.Experimental results confirmed the superiority and effectiveness of the proposed approach.The classification accuracy achieved by the proposed approach is(99.98%).展开更多
Arrhythmia has been classified using a variety of methods.Because of the dynamic nature of electrocardiogram(ECG)data,traditional handcrafted approaches are difficult to execute,making the machine learning(ML)solution...Arrhythmia has been classified using a variety of methods.Because of the dynamic nature of electrocardiogram(ECG)data,traditional handcrafted approaches are difficult to execute,making the machine learning(ML)solutions more appealing.Patients with cardiac arrhythmias can benefit from competent monitoring to save their lives.Cardiac arrhythmia classification and prediction have greatly improved in recent years.Arrhythmias are a category of conditions in which the heart's electrical activity is abnormally rapid or sluggish.Every year,it is one of the main reasons of mortality for both men and women,worldwide.For the classification of arrhythmias,this work proposes a novel technique based on optimized feature selection and optimized K-nearest neighbors(KNN)classifier.The proposed method makes advantage of the UCI repository,which has a 279-attribute high-dimensional cardiac arrhythmia dataset.The proposed approach is based on dividing cardiac arrhythmia patients into 16 groups based on the electrocardiography dataset’s features.The purpose is to design an efficient intelligent system employing the dipper throated optimization method to categorize cardiac arrhythmia patients.This method of comprehensive arrhythmia classification outperforms earlier methods presented in the literature.The achieved classification accuracy using the proposed approach is 99.8%.展开更多
Brugada phenocopies(BrP) are clinical entities that are etiologically distinct from true congenital Brugada syndrome. BrP are characterized by type 1 or type 2 Brugada electrocardiogram(ECG) patterns in precordial lea...Brugada phenocopies(BrP) are clinical entities that are etiologically distinct from true congenital Brugada syndrome. BrP are characterized by type 1 or type 2 Brugada electrocardiogram(ECG) patterns in precordial leads V1-V3. However, BrP are elicited by various un-derlying clinical conditions such as myocardial ischemia, pulmonary embolism, electrolyte abnormalities, or poor ECG filters. Upon resolution of the inciting underlying pathological condition, the BrP ECG subsequently nor-malizes. To date, reports have documented BrP in the context of singular clinical events. More recently, recur-rent BrP has been demonstrated in the context of re-current hypokalemia. This demonstrates clinical repro-ducibility, thereby advancing the concept of this new ECG phenomenon. The key to further understanding the pathophysiological mechanisms behind BrP requires experimental model validation in which these phenom-ena are reproduced under strictly controlled environ-mental conditions. The development of these validation models will help us determine whether BrP are tran-sient alterations of sodium channels that are not repro-ducible with a sodium channel provocative test or al-ternatively, a malfunction of other ion channels. In this editorial, we discuss the conceptual emergence of BrP as a new ECG phenomenon, review the progress made to date and identify opportunities for further investiga-tion. In addition, we also encourage investigators that are currently reporting on these cases to use the term BrP in order to facilitate literature searches and to help establish this emerging concept.展开更多
Early detection of sudden cardiac death may be used for surviving the life of cardiac patients. In this paper we have investigated an algorithm to detect and predict sudden cardiac death, by processing of heart rate v...Early detection of sudden cardiac death may be used for surviving the life of cardiac patients. In this paper we have investigated an algorithm to detect and predict sudden cardiac death, by processing of heart rate variability signal through the classical and time-frequency methods. At first, one minute of ECG signals, just before the cardiac death event are extracted and used to compute heart rate variability (HRV) signal. Five features in time domain and four features in frequency domain are extracted from the HRV signal and used as classical linear features. Then the Wigner Ville transform is applied to the HRV signal, and 11 extra features in the time-frequency (TF) domain are obtained. In order to improve the performance of classification, the principal component analysis (PCA) is applied to the obtained features vector. Finally a neural network classifier is applied to the reduced features. The obtained results show that the TF method can classify normal and SCD subjects, more efficiently than the classical methods. A MIT-BIH ECG database was used to evaluate the proposed method. The proposed method was implemented using MLP classifier and had 74.36% and 99.16% correct detection rate (accuracy) for classical features and TF method, respectively. Also, the accuracy of the KNN classifier were 73.87% and 96.04%.展开更多
Holter usually monitors electrocardiogram(ECG)signals for more than 24 hours to capture short-lived cardiac abnormalities.In view of the large amount of Holter data and the fact that the normal part accounts for the m...Holter usually monitors electrocardiogram(ECG)signals for more than 24 hours to capture short-lived cardiac abnormalities.In view of the large amount of Holter data and the fact that the normal part accounts for the majority,it is reasonable to design an algorithm that can automatically eliminate normal data segments as much as possible without missing any abnormal data segments,and then take the left segments to the doctors or the computer programs for further diagnosis.In this paper,we propose a preliminary abnormal segment screening method for Holter data.Based on long short-term memory(LSTM)networks,the prediction model is established and trained with the normal data of a monitored object.Then,on the basis of kernel density estimation,we learn the distribution law of prediction errors after applying the trained LSTM model to the regular data.Based on these,the preliminary abnormal ECG segment screening analysis is carried out without R wave detection.Experiments on the MIT-BIH arrhythmia database show that,under the condition of ensuring that no abnormal point is missed,53.89% of normal segments can be effectively obviated.This work can greatly reduce the workload of subsequent further processing.展开更多
Hyperkalemia is defined as serum potassium level of more than 5 mmol/L. Prompt identification of hyper-kalemia and appropriate management are critical, since severe hyperkalemia can lead to lethal cardiac dysrhythmias...Hyperkalemia is defined as serum potassium level of more than 5 mmol/L. Prompt identification of hyper-kalemia and appropriate management are critical, since severe hyperkalemia can lead to lethal cardiac dysrhythmias. There is a wide range of electrocardiogram (EKG) changes associated with hyperkalemia. The sequence of EKG changes has been previously described with limited information to correlate the level of potassium to a particular change in the EKG. This study aims to describe a correlation between the level of potassium and EKG changes in the presence or absence of certain diagnoses, to determine which EKG finding in the context of level of hyperkalemia, should be considered life-threatening and prompt emergency intervention. If a relationship between serum levels of potassium and EKG changes is significant, clinicians may be able to better monitor and treat hyperkalemic patients. This paper reviews the literature on hyperkalemia, potassium homeostasis and EKG changes attributed to elevated potassium.展开更多
AIM: To study the effects of low dose amitriptyline on cardiac conduction in children.METHODS: Secondary analysis of data obtained from a double-blind, randomized placebo-controlled trial, evaluating low dose amitript...AIM: To study the effects of low dose amitriptyline on cardiac conduction in children.METHODS: Secondary analysis of data obtained from a double-blind, randomized placebo-controlled trial, evaluating low dose amitriptyline in children with a diagnosis of functional abdominal pain, functional dyspepsia, and irritable bowel syndrome according to the Rome II criteria. Children 8-17 years of age were recruited from the pediatric gastroenterology clinics of 6 tertiary care centers in the United States. The electrocardiograms(EKGs) done prior to initiation of amitrityline and 1 mo after initiation of amitriptyline were examined. The changes in cardiac conduction were evaluated in patients and controls. RESULTS: Thirty children were included in the study. There were 12 patients, ages 9-17 years of both genders, in the amitriptyline treatment group and 18 patients, ages 9-17 years of both genders, in the placebotreatment group. None of the patients had any baseline EKG abnormality. Amitriptyline use was associated with an increase in heart rate(P = 0.024) and QTc interval(P = 0.0107) as compared to pre-EKGs. Children in the placebo group were also noted to present a statistically significant increase in QTc interval(P = 0.0498). None of the patients developed borderline QTc prolongation or long-QT syndrome after they were started on amitriptyline.CONCLUSION: The study findings suggest that once patients with functional gastrointestinal disorders have been screened for prolonged QTc interval on baseline EKG, they probably do not need a second EKG for reevaluation of cardiac conduction after starting low dose amitriptyline.展开更多
BACKGROUND:Post-infarct left ventricular free wall rupture(LVFWR)is not always an immediately catastrophic complication.The rupture can be subacute,allowing time for diagnosis and intervention.Accordingly,early recogn...BACKGROUND:Post-infarct left ventricular free wall rupture(LVFWR)is not always an immediately catastrophic complication.The rupture can be subacute,allowing time for diagnosis and intervention.Accordingly,early recognition of the entity may be lifesaving.METHODS:We present an electrocardiogram(ECG)change pattern in two cases,which was erroneously attributed to ischemia.Two women in their 80s were admitted to our institute after experiencing the sudden onset of chest pain.They were managed as anterior ST-segment elevation myocardial infarction without reperfusion treatment.Unfortunately,they experienced a recurrence of severe chest pain with cardiogenic shock during hospitalisation.The ECG recorded at that time showed a ST-segment re-elevation in infract-related leads.RESULTS:The two cases were regrettably received a misjudgement of reinfarction at first,and one of the patients even was administrated with tirofi ban.Afterwards the diagnosis of subacute LVFWR was made through antemortem echocardiography.CONCLUSION:New ST-segment elevation(STE)in infarct-associated leads,coupled with recurrence of chest pain and new-onset hypotension,may constitute the premonitory signs of a subacute LVFWR.展开更多
Background and Objective Cardiac pacing is an effective therapy in patients with bradycardia.Conventional right ventricular(RV)pacing is the source of ventricular dyssynchrony,leading to unfavorable clinical outcome.T...Background and Objective Cardiac pacing is an effective therapy in patients with bradycardia.Conventional right ventricular(RV)pacing is the source of ventricular dyssynchrony,leading to unfavorable clinical outcome.This study compared the electrocardiogram(ECG)characteristics during left bundle branch pacing(LBBP)with that during RV septal pacing(RVSP)which has been thought to be better than RV apical pacing.展开更多
A comprehensive study was conducted to differentiate cardiovascular disease (CVD) subjects from non-CVD subjects using short recording electrocardiogram (ECG) of 244 Malaysian adults in The MalaysianCohort project. An...A comprehensive study was conducted to differentiate cardiovascular disease (CVD) subjects from non-CVD subjects using short recording electrocardiogram (ECG) of 244 Malaysian adults in The MalaysianCohort project. An automated peak detection algorithm to detect nine fiducialpoints of electrocardiogram (ECG) was developed. Forty-eight features wereextracted in both time and frequency domains, including statistical featuresobtained from heart rate variability and Poincare plot analysis. These includefive new features derived from spectrum counts of five different frequencyranges. Feature selection was then made based on p-value and correlationmatrix. Selected features were used as input for five classifiers of artificialneural network (ANN), k-nearest neighbors (kNN), support vector machine(SVM), discriminant analysis (DA), and decision tree (DT). Results showedthat six features related to T wave were statistically significant in distinguishingCVD and non-CVD groups. ANN had performed the best with 94.44% specificity and 86.3% accuracy, followed by kNN with 80.56% specificity, 86.49%sensitivity and 83.56% accuracy. The novelties of this study were in providingalternative solutions to detect P-onset, P-offset, T-offset as well as QRS-onsetpoints using discrete wavelet transform method. Additionally, two out of thefive newly proposed spectral features were significant in differentiating bothgroups, at frequency ranges of 1–10 Hz and 5–10 Hz. The prediction outcomeswere also comparable to previous related studies and significantly importantin using ECG to predict cardiac-related events among CVD and non-CVDsubjects in the Malaysian population.展开更多
BACKGROUND Wellens syndrome is an electrocardiogram(ECG)pattern seen in high-risk patients with unstable angina pectoris.It is characterized by inverted or biphasic T-waves that change into positive or pseudo-normaliz...BACKGROUND Wellens syndrome is an electrocardiogram(ECG)pattern seen in high-risk patients with unstable angina pectoris.It is characterized by inverted or biphasic T-waves that change into positive or pseudo-normalized waves at precordial leads when the patient experiences an angina attack;however,the mechanism for this condition remains unclear.CASE SUMMARY A 47-year-old male patient experienced repeated,unprovoked episodes of chest pain for>20 d,with worsening during the previous day.On the day of admission,he experienced episodes of paroxysmal chest pain lasting more than 30 min,in addition to radiating pain to the left arm and exertional dyspnea.The patient presented to the emergency department with no chest pain or other discomfort at that time.ECG at presentation showed sinus tachycardia and Twave changes,which were identified as Wellens syndrome when combined with previous ECG findings.ECGs and myocardial enzymology examinations were normal when angina was present,but the ECG showed inverted or biphasic Twaves when angina was absent.After percutaneous coronary intervention,the ECGs demonstrated inverted or biphasic T-waves in the anterior precordial leads on days 0,1,and 2,but normal T-waves on day 3.The ECGs showed no subsequent ischemic ST-T-wave changes.CONCLUSION The Wellens syndrome pseudo-normalized T-waves likely reflect development of unstable angina pectoris into the hyperacute phase of ST-segment elevation myocardial infarction.展开更多
BACKGROUND: Comparison of different stroke locations had been focused in past researches in electrocardiogram (ECG) changes of cerebral stroke patients. Some researches neglected the heart disease in the illness histo...BACKGROUND: Comparison of different stroke locations had been focused in past researches in electrocardiogram (ECG) changes of cerebral stroke patients. Some researches neglected the heart disease in the illness history. OBJECTIVE: To discuss ECG changes in different infarction locations and size of acute cerebral infarction and compare with healthy people. DESIGN: Contrast observation. SETTING: Shanghai Ninth People’s Hospital. PARTICIPANTS: A total of 57 patients with cerebral infarction were selected from the Neurological Department of Ninth People’s Hospital of Shanghai from March 2003 to September 2005. They were diagnosed according to the criteria revised in the 4th National Cerebral Disease Conference and brain images. Patients who had heart disease were excluded. There were 32 males and 25 females, who were 65-84 years old. Among them, 23 cases were involved in right hemisphere, 34 cases in left one, 23 in base ganglion, 11 in brain stem, 9 in frontal lobe and 14 in other parts. According to their infarction size (plus size in every different scan), they were divided into three different groups: large-size group (n = 10) with size larger than 3.5 cm3, medium-size group (n = 13) with size between 1.5-3.5 cm3, and small-size group (n = 34) with size smaller than 1.5 cm3. Another 50 healthy subjects were regarded as control group. There were 29 males and 21 females aged 40-82 years. All these cases knew and agreed of the examination. METHODS: Patients received 12-lead ECG examinations within the first 6-24 hours of onset while control group received it at the same time. The HR, PR, QTc, QRS, T wave and ST changes were compared between the two groups. MAIN OUTCOME MEASURES: The ECG changes and differences in two hemispheres, in different infarction locations and sizes. RESULTS: All 57 patients and 50 healthy subjects were involved in the final analysis. ① ECG changes in infarction group and control group. There were no differences in HR, QRS time and cases with opposite T wave of infarction group compared with control group (P > 0.05). PR and QTc [(0.167±0.010), (0.383±0.029) s] in infarction group were longer than those in control group [(0.159±0.008), (0.361±0.022) s, t = 1.982, 2.363, P < 0.05, 0.01]. ST changes cases were 77% (44/57), which was more than those in control group [46% (23/50), χ2 = 11.072, P < 0.01]. ② Comparison of infarction in two hemispheres. HR, PR interval, QRS time, cases with opposite T wave and ST changes showed no differences (P > 0.05), and QTc interval in right hemisphere infarction was longer than left one [(0.391±0.054), (0.380±0.034) s, t =1.673, P < 0.05]. ③ ECG changes in different infarction locations. HR, PR interval, QTc interval, QRS time, cases with opposite T wave and ST changes showed no statistically significantly differences (P > 0.05). ④ ECG changes in different infarction sizes. HR, PR interval, QRS time showed no differences (P > 0.05). QTc interval in large size group was longer than the others [(0.399±0.044), (0.388±0.073), (0.378±0.124) s, F = 3.19, P < 0.05]. Cases with opposite T wave and ST changes in large size group were 80% (8/10), 100% (10/10), which were higher than those in medium size group [46% (6/13), 69% (9/13)] and small size group [44% (15/34), 35% (12/34), χ2 = 8.495, 10.538, P < 0.05, 0.01]. CONCLUSION: ① PR interval and QTc interval prolonged in cerebral infarction patients. Furthermore, QTc interval was more obvious in large size infarction group and right hemisphere infarction group. ② Infarction location did not affect the changes of ECG.展开更多
This paper presents a Novel Windowing Algorithm for Electrocardiogram Feature Extraction and Pattern Recognition. The work presented here deals with a simple and efficient way of detecting ECG features that are P, Q, ...This paper presents a Novel Windowing Algorithm for Electrocardiogram Feature Extraction and Pattern Recognition. The work presented here deals with a simple and efficient way of detecting ECG features that are P, Q, R, S and T waves. Windowing method is used to select these waves. Windows are based on varying R-R intervals. It has been tested on ECG simulator data and also on different records of the MIT-BIH arrhythmia database, producing satisfactory results. ECG timing intervals are also required for monitoring the cardiac condition of patients. Hence after feature detections ECG timing intervals like the PR interval, QRS duration, the QT interval, the QT corrected interval and Vent Rate are efficiently calculated using proposed Formulae.展开更多
Objective: To evaluate the treatment and prognostic value of 12-lead electrocardiogram in idiopathic pulmonary hypertension (IPAH). Methods: A total of 200 patients with initial diagnosis of IPAH were included to anal...Objective: To evaluate the treatment and prognostic value of 12-lead electrocardiogram in idiopathic pulmonary hypertension (IPAH). Methods: A total of 200 patients with initial diagnosis of IPAH were included to analyze the correlation between ECG variables and hemodynamics.Univariate and multivariate proportional hazards regression analysis (Cox regression analysis) were used to analyze the changes of ECG parameters and determine the ECG parameters related to IPAH patients. Results: Partial correlation analysis showed that the amplitude of R wave in V1 lead was correlated with mPAP(r=0.343, P<0.001), and the sum of the amplitude of R wave in V1 lead and S wave in V5 lead was correlated with mPAP(r=0.504, P<0.001). The amplitude of R wave in V1 lead was correlated with mortality (HR 3.154, P<0.001), and the sum of the amplitude of R wave in V1 lead and S wave in V5 lead was correlated with mortality (HR 5.056, P<0.001). After 3 months of treatment,ECG parameters and hemodynamic status were improved. Conclusion: The specific 12-lead ECG parameters can reflect the improvement of the treatment of patients with idiopathic pulmonary hypertension and help to evaluate the prognosis of patients with idiopathic pulmonary hypertension.展开更多
Brugada syndrome is a channelopathy that can be familial or sporadic. It is a major cause of sudden death in young people with no obvious heart structural abnormality. The electrocardiogram can be dynamic over time wi...Brugada syndrome is a channelopathy that can be familial or sporadic. It is a major cause of sudden death in young people with no obvious heart structural abnormality. The electrocardiogram can be dynamic over time with sometimes normalization. Several pathophysiological conditions are known to induce the electrocardiographic expression of the syndrome. We report here the case of a 65-year-old hypertensive man, without syncope or family sudden death history who was hospitalized for shigella gastroenteritis. Electrocardiogram during fever showed an incomplete block and ST segment elevation with negative T waves in V1 and V2 suggested type 1 Brugada syndrome. Troponin was negative. Electrocardiogram after fever recovered an incomplete right block and normalization of the ST segment. Electrocardiogram should be performed in patients admitted to the emergency unit for infectious syndrome in our countries. This may reveal a number of patients with Brugada syndrome abnormalities.展开更多
This report describes two cases of juvenile hypertrophic cardiomyopathy (HCM) in which prominent bi-atrial enlargement was observed on standard 12-lead electrocardiogram, suggesting inherent predis-position to extreme...This report describes two cases of juvenile hypertrophic cardiomyopathy (HCM) in which prominent bi-atrial enlargement was observed on standard 12-lead electrocardiogram, suggesting inherent predis-position to extreme enlargement and/or hypertrophy may exist in atrial myocardium in juvenile HCM. Comparative study between juvenile and adult HCM patients using a large sample size is required to confirm this hypothesis.展开更多
This paper presents an evaluation of a new biometric electrocardiogram (ECG) for individual authentication. We report the potential of ECG as a biometric and address the research concerns to use ECG-enabled biometric ...This paper presents an evaluation of a new biometric electrocardiogram (ECG) for individual authentication. We report the potential of ECG as a biometric and address the research concerns to use ECG-enabled biometric authentication system across a range of conditions. We present a method to delineate ECG waveforms and their end fiducials from each heartbeat. A new authentication strategy is proposed in this work, which uses the delineated features and taking decision for the identity of an individual with respect to the template database on the basis of match scores. Performance of the system is evaluated in a unimodal framework and in the multibiometric framework where ECG is combined with the face biometric and with the fingerprint biometric. The equal error rate (EER) result of the unimodal system is reported to 10.8%, while the EER results of the multibiometric systems are reported to 3.02% and 1.52%, respectively for the systems when ECG combined with the face biometric and ECG combined with the fingerprint biometric. The EER results of the combined systems prove that the ECG has an excellent source of supplementary information to a multibiometric system, despite it shows moderate performance in a unimodal framework. We critically evaluate the concerns involved to use ECG as a biometric for individual authentication such as, the lack of standardization of signal features and the presence of acquisition variations that make the data representation more difficult. In order to determine large scale performance, individuality of ECG remains to be examined.展开更多
Will exercise-induced cardiovascular workload be monitored by Electrocardiogram (ECG) waveform morphology? The discrimination ability of ECG morphology from 30 subjects was tested for distinguishing states between exe...Will exercise-induced cardiovascular workload be monitored by Electrocardiogram (ECG) waveform morphology? The discrimination ability of ECG morphology from 30 subjects was tested for distinguishing states between exercise and relaxation in terms of side lengths, lengths of high lines, angles, perimeters and areas of triangle QRS and triangle T. As a result, 4 characters from triangle QRS had significant differences (t test, p<0.05) for over 85% of subjects in distinguishing between exercise states and relaxation states, which were: ratio of QR side length to RS side length in triangle QRS, angle S and angle Q, as well as the ratio between them. Moreover, ratio of angle S to angle Q had significant differences (t test, p<0.05) for all subjects. In conclusion, triangle characters in ECG could be used to distinguish exercise states from relaxation states.展开更多
基金Supported by the NSFC-Zhejiang Joint Fund for the Integration of Industrialization and Informatization(U1909208)the Science and Technology Major Project of Changsha(kh2202004)the Changsha Municipal Natural Science Foundation(kq2202106).
文摘Electrocardiogram(ECG)is a low-cost,simple,fast,and non-invasive test.It can reflect the heart’s electrical activity and provide valuable diagnostic clues about the health of the entire body.Therefore,ECG has been widely used in various biomedical applications such as arrhythmia detection,disease-specific detection,mortality prediction,and biometric recognition.In recent years,ECG-related studies have been carried out using a variety of publicly available datasets,with many differences in the datasets used,data preprocessing methods,targeted challenges,and modeling and analysis techniques.Here we systematically summarize and analyze the ECGbased automatic analysis methods and applications.Specifically,we first reviewed 22 commonly used ECG public datasets and provided an overview of data preprocessing processes.Then we described some of the most widely used applications of ECG signals and analyzed the advanced methods involved in these applications.Finally,we elucidated some of the challenges in ECG analysis and provided suggestions for further research.
文摘Aslanger’s sign,also known as the arterial pulse tapping artifact or electromechanical association artifact,is an electrocardiographic artifact caused by arterial pulsation at the site where the limb leads of the standard 12-lead electrocardiogram near the radial or posterior tibial arteries are positioned,particularly in hyperdynamic states.[1–8]It occurs in every cardiac cycle with a constant coupling interval between the QRS complex and artifact.This synchronization with the underlying heart rhythm makes it less likely to be recognized as an artifact compared to unsynchronized artifacts,such as those caused by limb movement and inadequate contact between the electrode and skin.[1,2,7,8]Almost all reported cases of Aslanger’s sign exhibit an unusual waveform morphology in all 12 leads except one of the standard 12-lead electrocardiogram.This sign is often confused with an electrocardiographic finding commonly observed during acute coronary events.
文摘Electrocardiogram(ECG)signal is a measure of the heart’s electrical activity.Recently,ECG detection and classification have benefited from the use of computer-aided systems by cardiologists.The goal of this paper is to improve the accuracy of ECG classification by combining the Dipper Throated Optimization(DTO)and Differential Evolution Algorithm(DEA)into a unified algorithm to optimize the hyperparameters of neural network(NN)for boosting the ECG classification accuracy.In addition,we proposed a new feature selection method for selecting the significant feature that can improve the overall performance.To prove the superiority of the proposed approach,several experimentswere conducted to compare the results achieved by the proposed approach and other competing approaches.Moreover,statistical analysis is performed to study the significance and stability of the proposed approach using Wilcoxon and ANOVA tests.Experimental results confirmed the superiority and effectiveness of the proposed approach.The classification accuracy achieved by the proposed approach is(99.98%).
文摘Arrhythmia has been classified using a variety of methods.Because of the dynamic nature of electrocardiogram(ECG)data,traditional handcrafted approaches are difficult to execute,making the machine learning(ML)solutions more appealing.Patients with cardiac arrhythmias can benefit from competent monitoring to save their lives.Cardiac arrhythmia classification and prediction have greatly improved in recent years.Arrhythmias are a category of conditions in which the heart's electrical activity is abnormally rapid or sluggish.Every year,it is one of the main reasons of mortality for both men and women,worldwide.For the classification of arrhythmias,this work proposes a novel technique based on optimized feature selection and optimized K-nearest neighbors(KNN)classifier.The proposed method makes advantage of the UCI repository,which has a 279-attribute high-dimensional cardiac arrhythmia dataset.The proposed approach is based on dividing cardiac arrhythmia patients into 16 groups based on the electrocardiography dataset’s features.The purpose is to design an efficient intelligent system employing the dipper throated optimization method to categorize cardiac arrhythmia patients.This method of comprehensive arrhythmia classification outperforms earlier methods presented in the literature.The achieved classification accuracy using the proposed approach is 99.8%.
文摘Brugada phenocopies(BrP) are clinical entities that are etiologically distinct from true congenital Brugada syndrome. BrP are characterized by type 1 or type 2 Brugada electrocardiogram(ECG) patterns in precordial leads V1-V3. However, BrP are elicited by various un-derlying clinical conditions such as myocardial ischemia, pulmonary embolism, electrolyte abnormalities, or poor ECG filters. Upon resolution of the inciting underlying pathological condition, the BrP ECG subsequently nor-malizes. To date, reports have documented BrP in the context of singular clinical events. More recently, recur-rent BrP has been demonstrated in the context of re-current hypokalemia. This demonstrates clinical repro-ducibility, thereby advancing the concept of this new ECG phenomenon. The key to further understanding the pathophysiological mechanisms behind BrP requires experimental model validation in which these phenom-ena are reproduced under strictly controlled environ-mental conditions. The development of these validation models will help us determine whether BrP are tran-sient alterations of sodium channels that are not repro-ducible with a sodium channel provocative test or al-ternatively, a malfunction of other ion channels. In this editorial, we discuss the conceptual emergence of BrP as a new ECG phenomenon, review the progress made to date and identify opportunities for further investiga-tion. In addition, we also encourage investigators that are currently reporting on these cases to use the term BrP in order to facilitate literature searches and to help establish this emerging concept.
文摘Early detection of sudden cardiac death may be used for surviving the life of cardiac patients. In this paper we have investigated an algorithm to detect and predict sudden cardiac death, by processing of heart rate variability signal through the classical and time-frequency methods. At first, one minute of ECG signals, just before the cardiac death event are extracted and used to compute heart rate variability (HRV) signal. Five features in time domain and four features in frequency domain are extracted from the HRV signal and used as classical linear features. Then the Wigner Ville transform is applied to the HRV signal, and 11 extra features in the time-frequency (TF) domain are obtained. In order to improve the performance of classification, the principal component analysis (PCA) is applied to the obtained features vector. Finally a neural network classifier is applied to the reduced features. The obtained results show that the TF method can classify normal and SCD subjects, more efficiently than the classical methods. A MIT-BIH ECG database was used to evaluate the proposed method. The proposed method was implemented using MLP classifier and had 74.36% and 99.16% correct detection rate (accuracy) for classical features and TF method, respectively. Also, the accuracy of the KNN classifier were 73.87% and 96.04%.
文摘Holter usually monitors electrocardiogram(ECG)signals for more than 24 hours to capture short-lived cardiac abnormalities.In view of the large amount of Holter data and the fact that the normal part accounts for the majority,it is reasonable to design an algorithm that can automatically eliminate normal data segments as much as possible without missing any abnormal data segments,and then take the left segments to the doctors or the computer programs for further diagnosis.In this paper,we propose a preliminary abnormal segment screening method for Holter data.Based on long short-term memory(LSTM)networks,the prediction model is established and trained with the normal data of a monitored object.Then,on the basis of kernel density estimation,we learn the distribution law of prediction errors after applying the trained LSTM model to the regular data.Based on these,the preliminary abnormal ECG segment screening analysis is carried out without R wave detection.Experiments on the MIT-BIH arrhythmia database show that,under the condition of ensuring that no abnormal point is missed,53.89% of normal segments can be effectively obviated.This work can greatly reduce the workload of subsequent further processing.
文摘Hyperkalemia is defined as serum potassium level of more than 5 mmol/L. Prompt identification of hyper-kalemia and appropriate management are critical, since severe hyperkalemia can lead to lethal cardiac dysrhythmias. There is a wide range of electrocardiogram (EKG) changes associated with hyperkalemia. The sequence of EKG changes has been previously described with limited information to correlate the level of potassium to a particular change in the EKG. This study aims to describe a correlation between the level of potassium and EKG changes in the presence or absence of certain diagnoses, to determine which EKG finding in the context of level of hyperkalemia, should be considered life-threatening and prompt emergency intervention. If a relationship between serum levels of potassium and EKG changes is significant, clinicians may be able to better monitor and treat hyperkalemic patients. This paper reviews the literature on hyperkalemia, potassium homeostasis and EKG changes attributed to elevated potassium.
文摘AIM: To study the effects of low dose amitriptyline on cardiac conduction in children.METHODS: Secondary analysis of data obtained from a double-blind, randomized placebo-controlled trial, evaluating low dose amitriptyline in children with a diagnosis of functional abdominal pain, functional dyspepsia, and irritable bowel syndrome according to the Rome II criteria. Children 8-17 years of age were recruited from the pediatric gastroenterology clinics of 6 tertiary care centers in the United States. The electrocardiograms(EKGs) done prior to initiation of amitrityline and 1 mo after initiation of amitriptyline were examined. The changes in cardiac conduction were evaluated in patients and controls. RESULTS: Thirty children were included in the study. There were 12 patients, ages 9-17 years of both genders, in the amitriptyline treatment group and 18 patients, ages 9-17 years of both genders, in the placebotreatment group. None of the patients had any baseline EKG abnormality. Amitriptyline use was associated with an increase in heart rate(P = 0.024) and QTc interval(P = 0.0107) as compared to pre-EKGs. Children in the placebo group were also noted to present a statistically significant increase in QTc interval(P = 0.0498). None of the patients developed borderline QTc prolongation or long-QT syndrome after they were started on amitriptyline.CONCLUSION: The study findings suggest that once patients with functional gastrointestinal disorders have been screened for prolonged QTc interval on baseline EKG, they probably do not need a second EKG for reevaluation of cardiac conduction after starting low dose amitriptyline.
基金supported by National Natural Science Foundation of China General Program(81970298)the National Key R&D Project(2016YFC1301300,2016YFC1301303)
文摘BACKGROUND:Post-infarct left ventricular free wall rupture(LVFWR)is not always an immediately catastrophic complication.The rupture can be subacute,allowing time for diagnosis and intervention.Accordingly,early recognition of the entity may be lifesaving.METHODS:We present an electrocardiogram(ECG)change pattern in two cases,which was erroneously attributed to ischemia.Two women in their 80s were admitted to our institute after experiencing the sudden onset of chest pain.They were managed as anterior ST-segment elevation myocardial infarction without reperfusion treatment.Unfortunately,they experienced a recurrence of severe chest pain with cardiogenic shock during hospitalisation.The ECG recorded at that time showed a ST-segment re-elevation in infract-related leads.RESULTS:The two cases were regrettably received a misjudgement of reinfarction at first,and one of the patients even was administrated with tirofi ban.Afterwards the diagnosis of subacute LVFWR was made through antemortem echocardiography.CONCLUSION:New ST-segment elevation(STE)in infarct-associated leads,coupled with recurrence of chest pain and new-onset hypotension,may constitute the premonitory signs of a subacute LVFWR.
文摘Background and Objective Cardiac pacing is an effective therapy in patients with bradycardia.Conventional right ventricular(RV)pacing is the source of ventricular dyssynchrony,leading to unfavorable clinical outcome.This study compared the electrocardiogram(ECG)characteristics during left bundle branch pacing(LBBP)with that during RV septal pacing(RVSP)which has been thought to be better than RV apical pacing.
基金This study was supported by the Ministry of Education Malaysia’s Fundamental Research Grant Scheme FRGS/1/2019/TK04/UKM/02/4TMC research was funded by a top-down grant from the Ministry of Education Malaysia(Grant Number PDE48).
文摘A comprehensive study was conducted to differentiate cardiovascular disease (CVD) subjects from non-CVD subjects using short recording electrocardiogram (ECG) of 244 Malaysian adults in The MalaysianCohort project. An automated peak detection algorithm to detect nine fiducialpoints of electrocardiogram (ECG) was developed. Forty-eight features wereextracted in both time and frequency domains, including statistical featuresobtained from heart rate variability and Poincare plot analysis. These includefive new features derived from spectrum counts of five different frequencyranges. Feature selection was then made based on p-value and correlationmatrix. Selected features were used as input for five classifiers of artificialneural network (ANN), k-nearest neighbors (kNN), support vector machine(SVM), discriminant analysis (DA), and decision tree (DT). Results showedthat six features related to T wave were statistically significant in distinguishingCVD and non-CVD groups. ANN had performed the best with 94.44% specificity and 86.3% accuracy, followed by kNN with 80.56% specificity, 86.49%sensitivity and 83.56% accuracy. The novelties of this study were in providingalternative solutions to detect P-onset, P-offset, T-offset as well as QRS-onsetpoints using discrete wavelet transform method. Additionally, two out of thefive newly proposed spectral features were significant in differentiating bothgroups, at frequency ranges of 1–10 Hz and 5–10 Hz. The prediction outcomeswere also comparable to previous related studies and significantly importantin using ECG to predict cardiac-related events among CVD and non-CVDsubjects in the Malaysian population.
文摘BACKGROUND Wellens syndrome is an electrocardiogram(ECG)pattern seen in high-risk patients with unstable angina pectoris.It is characterized by inverted or biphasic T-waves that change into positive or pseudo-normalized waves at precordial leads when the patient experiences an angina attack;however,the mechanism for this condition remains unclear.CASE SUMMARY A 47-year-old male patient experienced repeated,unprovoked episodes of chest pain for>20 d,with worsening during the previous day.On the day of admission,he experienced episodes of paroxysmal chest pain lasting more than 30 min,in addition to radiating pain to the left arm and exertional dyspnea.The patient presented to the emergency department with no chest pain or other discomfort at that time.ECG at presentation showed sinus tachycardia and Twave changes,which were identified as Wellens syndrome when combined with previous ECG findings.ECGs and myocardial enzymology examinations were normal when angina was present,but the ECG showed inverted or biphasic Twaves when angina was absent.After percutaneous coronary intervention,the ECGs demonstrated inverted or biphasic T-waves in the anterior precordial leads on days 0,1,and 2,but normal T-waves on day 3.The ECGs showed no subsequent ischemic ST-T-wave changes.CONCLUSION The Wellens syndrome pseudo-normalized T-waves likely reflect development of unstable angina pectoris into the hyperacute phase of ST-segment elevation myocardial infarction.
文摘BACKGROUND: Comparison of different stroke locations had been focused in past researches in electrocardiogram (ECG) changes of cerebral stroke patients. Some researches neglected the heart disease in the illness history. OBJECTIVE: To discuss ECG changes in different infarction locations and size of acute cerebral infarction and compare with healthy people. DESIGN: Contrast observation. SETTING: Shanghai Ninth People’s Hospital. PARTICIPANTS: A total of 57 patients with cerebral infarction were selected from the Neurological Department of Ninth People’s Hospital of Shanghai from March 2003 to September 2005. They were diagnosed according to the criteria revised in the 4th National Cerebral Disease Conference and brain images. Patients who had heart disease were excluded. There were 32 males and 25 females, who were 65-84 years old. Among them, 23 cases were involved in right hemisphere, 34 cases in left one, 23 in base ganglion, 11 in brain stem, 9 in frontal lobe and 14 in other parts. According to their infarction size (plus size in every different scan), they were divided into three different groups: large-size group (n = 10) with size larger than 3.5 cm3, medium-size group (n = 13) with size between 1.5-3.5 cm3, and small-size group (n = 34) with size smaller than 1.5 cm3. Another 50 healthy subjects were regarded as control group. There were 29 males and 21 females aged 40-82 years. All these cases knew and agreed of the examination. METHODS: Patients received 12-lead ECG examinations within the first 6-24 hours of onset while control group received it at the same time. The HR, PR, QTc, QRS, T wave and ST changes were compared between the two groups. MAIN OUTCOME MEASURES: The ECG changes and differences in two hemispheres, in different infarction locations and sizes. RESULTS: All 57 patients and 50 healthy subjects were involved in the final analysis. ① ECG changes in infarction group and control group. There were no differences in HR, QRS time and cases with opposite T wave of infarction group compared with control group (P > 0.05). PR and QTc [(0.167±0.010), (0.383±0.029) s] in infarction group were longer than those in control group [(0.159±0.008), (0.361±0.022) s, t = 1.982, 2.363, P < 0.05, 0.01]. ST changes cases were 77% (44/57), which was more than those in control group [46% (23/50), χ2 = 11.072, P < 0.01]. ② Comparison of infarction in two hemispheres. HR, PR interval, QRS time, cases with opposite T wave and ST changes showed no differences (P > 0.05), and QTc interval in right hemisphere infarction was longer than left one [(0.391±0.054), (0.380±0.034) s, t =1.673, P < 0.05]. ③ ECG changes in different infarction locations. HR, PR interval, QTc interval, QRS time, cases with opposite T wave and ST changes showed no statistically significantly differences (P > 0.05). ④ ECG changes in different infarction sizes. HR, PR interval, QRS time showed no differences (P > 0.05). QTc interval in large size group was longer than the others [(0.399±0.044), (0.388±0.073), (0.378±0.124) s, F = 3.19, P < 0.05]. Cases with opposite T wave and ST changes in large size group were 80% (8/10), 100% (10/10), which were higher than those in medium size group [46% (6/13), 69% (9/13)] and small size group [44% (15/34), 35% (12/34), χ2 = 8.495, 10.538, P < 0.05, 0.01]. CONCLUSION: ① PR interval and QTc interval prolonged in cerebral infarction patients. Furthermore, QTc interval was more obvious in large size infarction group and right hemisphere infarction group. ② Infarction location did not affect the changes of ECG.
文摘This paper presents a Novel Windowing Algorithm for Electrocardiogram Feature Extraction and Pattern Recognition. The work presented here deals with a simple and efficient way of detecting ECG features that are P, Q, R, S and T waves. Windowing method is used to select these waves. Windows are based on varying R-R intervals. It has been tested on ECG simulator data and also on different records of the MIT-BIH arrhythmia database, producing satisfactory results. ECG timing intervals are also required for monitoring the cardiac condition of patients. Hence after feature detections ECG timing intervals like the PR interval, QRS duration, the QT interval, the QT corrected interval and Vent Rate are efficiently calculated using proposed Formulae.
基金This study was supported by Jiangsu Provincial Natural Science Foundation Project(BK20151355)Jiangsu Provincial Traditional Chinese Medicine Bureau Project(LB09041)Nanjing University of Chinese Medicine Project(NZYLCZX2015-01)
文摘Objective: To evaluate the treatment and prognostic value of 12-lead electrocardiogram in idiopathic pulmonary hypertension (IPAH). Methods: A total of 200 patients with initial diagnosis of IPAH were included to analyze the correlation between ECG variables and hemodynamics.Univariate and multivariate proportional hazards regression analysis (Cox regression analysis) were used to analyze the changes of ECG parameters and determine the ECG parameters related to IPAH patients. Results: Partial correlation analysis showed that the amplitude of R wave in V1 lead was correlated with mPAP(r=0.343, P<0.001), and the sum of the amplitude of R wave in V1 lead and S wave in V5 lead was correlated with mPAP(r=0.504, P<0.001). The amplitude of R wave in V1 lead was correlated with mortality (HR 3.154, P<0.001), and the sum of the amplitude of R wave in V1 lead and S wave in V5 lead was correlated with mortality (HR 5.056, P<0.001). After 3 months of treatment,ECG parameters and hemodynamic status were improved. Conclusion: The specific 12-lead ECG parameters can reflect the improvement of the treatment of patients with idiopathic pulmonary hypertension and help to evaluate the prognosis of patients with idiopathic pulmonary hypertension.
文摘Brugada syndrome is a channelopathy that can be familial or sporadic. It is a major cause of sudden death in young people with no obvious heart structural abnormality. The electrocardiogram can be dynamic over time with sometimes normalization. Several pathophysiological conditions are known to induce the electrocardiographic expression of the syndrome. We report here the case of a 65-year-old hypertensive man, without syncope or family sudden death history who was hospitalized for shigella gastroenteritis. Electrocardiogram during fever showed an incomplete block and ST segment elevation with negative T waves in V1 and V2 suggested type 1 Brugada syndrome. Troponin was negative. Electrocardiogram after fever recovered an incomplete right block and normalization of the ST segment. Electrocardiogram should be performed in patients admitted to the emergency unit for infectious syndrome in our countries. This may reveal a number of patients with Brugada syndrome abnormalities.
文摘This report describes two cases of juvenile hypertrophic cardiomyopathy (HCM) in which prominent bi-atrial enlargement was observed on standard 12-lead electrocardiogram, suggesting inherent predis-position to extreme enlargement and/or hypertrophy may exist in atrial myocardium in juvenile HCM. Comparative study between juvenile and adult HCM patients using a large sample size is required to confirm this hypothesis.
文摘This paper presents an evaluation of a new biometric electrocardiogram (ECG) for individual authentication. We report the potential of ECG as a biometric and address the research concerns to use ECG-enabled biometric authentication system across a range of conditions. We present a method to delineate ECG waveforms and their end fiducials from each heartbeat. A new authentication strategy is proposed in this work, which uses the delineated features and taking decision for the identity of an individual with respect to the template database on the basis of match scores. Performance of the system is evaluated in a unimodal framework and in the multibiometric framework where ECG is combined with the face biometric and with the fingerprint biometric. The equal error rate (EER) result of the unimodal system is reported to 10.8%, while the EER results of the multibiometric systems are reported to 3.02% and 1.52%, respectively for the systems when ECG combined with the face biometric and ECG combined with the fingerprint biometric. The EER results of the combined systems prove that the ECG has an excellent source of supplementary information to a multibiometric system, despite it shows moderate performance in a unimodal framework. We critically evaluate the concerns involved to use ECG as a biometric for individual authentication such as, the lack of standardization of signal features and the presence of acquisition variations that make the data representation more difficult. In order to determine large scale performance, individuality of ECG remains to be examined.
文摘Will exercise-induced cardiovascular workload be monitored by Electrocardiogram (ECG) waveform morphology? The discrimination ability of ECG morphology from 30 subjects was tested for distinguishing states between exercise and relaxation in terms of side lengths, lengths of high lines, angles, perimeters and areas of triangle QRS and triangle T. As a result, 4 characters from triangle QRS had significant differences (t test, p<0.05) for over 85% of subjects in distinguishing between exercise states and relaxation states, which were: ratio of QR side length to RS side length in triangle QRS, angle S and angle Q, as well as the ratio between them. Moreover, ratio of angle S to angle Q had significant differences (t test, p<0.05) for all subjects. In conclusion, triangle characters in ECG could be used to distinguish exercise states from relaxation states.
