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Sample records for surface electrocardiogram ecg

  1. ECG Electrocardiogram (For Parents)

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español ECG (Electrocardiogram) KidsHealth / For Parents / ECG (Electrocardiogram) Print en español Electrocardiograma (ECG) An electrocardiogram (ECG ...

  2. ECG-ViEW II, a freely accessible electrocardiogram database

    Science.gov (United States)

    Park, Man Young; Lee, Sukhoon; Jeon, Min Seok; Yoon, Dukyong; Park, Rae Woong

    2017-01-01

    The Electrocardiogram Vigilance with Electronic data Warehouse II (ECG-ViEW II) is a large, single-center database comprising numeric parameter data of the surface electrocardiograms of all patients who underwent testing from 1 June 1994 to 31 July 2013. The electrocardiographic data include the test date, clinical department, RR interval, PR interval, QRS duration, QT interval, QTc interval, P axis, QRS axis, and T axis. These data are connected with patient age, sex, ethnicity, comorbidities, age-adjusted Charlson comorbidity index, prescribed drugs, and electrolyte levels. This longitudinal observational database contains 979,273 electrocardiograms from 461,178 patients over a 19-year study period. This database can provide an opportunity to study electrocardiographic changes caused by medications, disease, or other demographic variables. ECG-ViEW II is freely available at http://www.ecgview.org. PMID:28437484

  3. Extraction of fetal electrocardiogram (ECG) by extended state ...

    Indian Academy of Sciences (India)

    Fetal electrocardiogram (ECG) gives information about the health status of fetus and so, an early diagnosis of any cardiac defect before delivery increases the effectiveness of appropriate treatment. In this paper, authors investigate the use of adaptive neuro-fuzzy inference system (ANFIS) with extended Kalman filter for fetal ...

  4. Electrocardiogram

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003868.htm Electrocardiogram To use the sharing features on this page, please enable JavaScript. An electrocardiogram (ECG) is a test that records the electrical ...

  5. Reliability of Computer Analysis of Electrocardiograms (ECG) of ...

    African Journals Online (AJOL)

    Background: Computer programmes have been introduced to electrocardiography (ECG) with most physicians in Africa depending on computer interpretation of ECG. This study was undertaken to evaluate the reliability of computer interpretation of the 12-Lead ECG in the Black race. Methodology: Using the SCHILLER ...

  6. Microprocessor-based simulator of surface ECG signals

    International Nuclear Information System (INIS)

    MartInez, A E; Rossi, E; Siri, L Nicola

    2007-01-01

    In this work, a simulator of surface electrocardiogram recorded signals (ECG) is presented. The device, based on a microcontroller and commanded by a personal computer, produces an analog signal resembling actual ECGs, not only in time course and voltage levels, but also in source impedance. The simulator is a useful tool for electrocardiograph calibration and monitoring, to incorporate as well in educational tasks and in clinical environments for early detection of faulty behaviour

  7. Electrocardiogram (ECG Signal Modeling and Noise Reduction Using Hopfield Neural Networks

    Directory of Open Access Journals (Sweden)

    F. Bagheri

    2013-02-01

    Full Text Available The Electrocardiogram (ECG signal is one of the diagnosing approaches to detect heart disease. In this study the Hopfield Neural Network (HNN is applied and proposed for ECG signal modeling and noise reduction. The Hopfield Neural Network (HNN is a recurrent neural network that stores the information in a dynamic stable pattern. This algorithm retrieves a pattern stored in memory in response to the presentation of an incomplete or noisy version of that pattern. Computer simulation results show that this method can successfully model the ECG signal and remove high-frequency noise.

  8. Extraction of fetal electrocardiogram (ECG) by extended state ...

    Indian Academy of Sciences (India)

    So by observing above characteristics appropriate treatment is usually performed (Deans &. Steer 1994). ... the low power of the fetal ECG signal which is contaminated by various sources of interference. These sources ... By using low noise electronic amplifiers with high common mode rejection ratio, the effect of the 50 Hz ...

  9. Use of electrocardiogram (ECG) electrodes for Bioelectrical Impedance Analysis (BIA)

    Science.gov (United States)

    Caicedo-Eraso, J. C.; González-Correa, C. H.; González-Correa, C. A.

    2012-12-01

    BIA is a safe, noninvasive, portable and relatively inexpensive method of estimating body composition that is practical and suitable for individual use and large-scale studies. However, the cost of the electrodes recommended by some BIA manufacturers is too high for developing countries; where very often the long and complicated process of importation reduces the time they can be used. The purpose of this study was to evaluate the use of two types of ECG electrodes (2290 and 2228 by 3M®) in BIA measurements to decrease the costs of the test. The results showed that the 2228 ECG electrodes can be used in BIA measurements for adult's body composition assessment. These electrodes are available in the domestic market and their costs are 92% lower than the electrodes recommended by manufacturer. The results show a new cost-benefit relation for BIA method and make this a more accessible tool for individual tests, large-scale researches and studies in the community.

  10. Design and Simulation of Electrocardiogram Circuit with Automatic Analysis of ECG Signal

    Directory of Open Access Journals (Sweden)

    Tosin Jemilehin

    2016-10-01

    Full Text Available An electrocardiogram (ECG is the graphical record of bioelectric signal generated by the human body during cardiac cycle, it tells a lot about the medical status of an individual. A typical ECG waveform consist of the P, Q, R, S and T wave. The automatic ECG signal analysis comprises of using computational method/approach in extracting important features and classification of ECG waveform. This paper presents a concise ECG circuit design using an instrumentation amplifier and a band-pass passive filter. It also present the process involved in analysis of ECG signal. The first stage is the pre-filtering stage, followed by feature extraction of the signal. QRS complex is first extracted followed by P and T wave detection, also the FFT of the signal is also extracted. These features are fed into the classifier for proper classification. A pattern recognition neural network is used for classification, prior to the full deployment of the neural network, it is trained by pre-recorded ECG signal downloaded from the MIT/BIH Arrhythmias database. The neural network gave a satisfactory result with accuracy of around 87%.The whole ECG signal analysis is packaged into a MATLAB GUI for ease of use

  11. An Investigation on the Effect of Extremely Low Frequency Pulsed Electromagnetic Fields on Human Electrocardiograms (ECGs)

    Science.gov (United States)

    Fang, Qiang; Mahmoud, Seedahmed S.; Yan, Jiayong; Li, Hui

    2016-01-01

    For this investigation, we studied the effects of extremely low frequency pulse electromagnetic fields (ELF-PEMF) on the human cardiac signal. Electrocardiograms (ECGs) of 22 healthy volunteers before and after a short duration of ELF-PEMF exposure were recorded. The experiment was conducted under single-blind conditions. The root mean square (RMS) value of the recorded data was considered as comparison criteria. We also measured and analysed four important ECG time intervals before and after ELF-PEMF exposure. Results revealed that the RMS value of the ECG recordings from 18 participants (81.8% of the total participants) increased with a mean value of 3.72%. The increase in ECG voltage levels was then verified by a second experimental protocol with a control exposure. In addition to this, we used hyperbolic T-distributions (HTD) in the analysis of ECG signals to verify the change in the RR interval. It was found that there were small shifts in the frequency-domain signal before and after EMF exposure. This shift has an influence on all frequency components of the ECG signals, as all spectrums were shifted. It is shown from this investigation that a short time exposure to ELF-PEMF can affect the properties of ECG signals. Further study is needed to consolidate this finding and discover more on the biological effects of ELF-PEMF on human physiological processes. PMID:27886102

  12. An Investigation on the Effect of Extremely Low Frequency Pulsed Electromagnetic Fields on Human Electrocardiograms (ECGs).

    Science.gov (United States)

    Fang, Qiang; Mahmoud, Seedahmed S; Yan, Jiayong; Li, Hui

    2016-11-23

    For this investigation, we studied the effects of extremely low frequency pulse electromagnetic fields (ELF-PEMF) on the human cardiac signal. Electrocardiograms (ECGs) of 22 healthy volunteers before and after a short duration of ELF-PEMF exposure were recorded. The experiment was conducted under single-blind conditions. The root mean square (RMS) value of the recorded data was considered as comparison criteria. We also measured and analysed four important ECG time intervals before and after ELF-PEMF exposure. Results revealed that the RMS value of the ECG recordings from 18 participants (81.8% of the total participants) increased with a mean value of 3.72%. The increase in ECG voltage levels was then verified by a second experimental protocol with a control exposure. In addition to this, we used hyperbolic T-distributions (HTD) in the analysis of ECG signals to verify the change in the RR interval. It was found that there were small shifts in the frequency-domain signal before and after EMF exposure. This shift has an influence on all frequency components of the ECG signals, as all spectrums were shifted. It is shown from this investigation that a short time exposure to ELF-PEMF can affect the properties of ECG signals. Further study is needed to consolidate this finding and discover more on the biological effects of ELF-PEMF on human physiological processes.

  13. Electrocardiogram (ECG) for the Prediction of Incident Atrial Fibrillation: An Overview.

    Science.gov (United States)

    Aizawa, Yoshifusa; Watanabe, Hiroshi; Okumura, Ken

    2017-12-01

    Electrocardiograms (ECGs) have been employed to medically evaluate participants in population-based studies, and ECG-derived predictors have been reported for incident atrial fibrillation (AF). Here, we reviewed the status of ECG in predicting new-onset AF. We surveyed population-based studies and revealed ECG variables to be risk factors for incident AF. When available, the predictive values of each ECG risk marker were calculated. Both the atrium-related and ventricle-related ECG variables were risk factors for incident AF, with significant hazard risks (HRs) even after multivariate adjustments. The risk factors included P-wave indices (maximum P-wave duration, its dispersion or variation and P-wave morphology) and premature atrial contractions (PACs) or runs. In addition, left ventricular hypertrophy (LVH), ST-T abnormalities, intraventricular conduction delay, QTc interval and premature ventricular contractions (PVCs) or runs were a risk of incident AF. An HR of greater than 2.0 was observed in the upper 5th percentile of the P-wave durations, P-wave durations greater than 130 ms, P-wave morpholyg, PACs (PVCs) or runs, LVH, QTc and left anterior fascicular blocks. The sensitivity , specificity and the positive and negative predictive values were 3.6-53.8%, 61.7-97.9%, 2.9-61.7% and 77.4-97.7%, respectively. ECG variables are risk factors for incident AF. The correlation between the ECG-derived AF predictors, especially P-wave indices, and underlying diseases and the effects of the reversal of the ECG-derived predictors on incident AF by treatment of comorbidities require further study.

  14. Electrocardiogram: his bundle potentials can be recorded noninvasively beat by beat on surface electrocardiogram.

    Science.gov (United States)

    Wang, Gaopin; Liu, Renguang; Chang, Qinghua; Xu, Zhaolong; Zhang, Yingjie; Pan, Dianzhu

    2017-03-15

    The micro waveform of His bundle potential can't be recorded beat-to-beat on surface electrocardiogram yet. We have found that the micro-wavelets before QRS complex may be related to atrioventricular conduction system potentials. This study is to explore the possibility of His bundle potential can be noninvasively recorded on surface electrocardiogram. We randomized 65 patients undergoing radiofrequency catheter ablation of paroxysmal superventricular tachycardia (exclude overt Wolff-Parkinson-White syndrome) to receive "conventional electrocardiogram" and "new electrocardiogram" before the procedure. His bundle electrogram was collected during the procedure. Comparative analysis of PA s (PA interval recorded on surface electrocardiogram), AH s (AH interval recorded on surface electrocardiogram) and HV s (HV interval recorded on surface electrocardiogram) interval recorded on surface "new electrocardiogram" and PA, AH, HV interval recorded on His bundle electrogram was investigated. There was no difference (P > 0.05) between groups in HV s interval (49.63 ± 6.19 ms) and HV interval (49.35 ± 6.49 ms). Results of correlational analysis found that HV S interval was significantly positively associated with HV interval (r = 0.929; P electrocardiogram. Noninvasive His bundle potential tracing might represent a new method for locating the site of atrioventricular block and identifying the origin of a wide QRS complex.

  15. An Accuracy Study of the Intracavitary Electrocardiogram (IC-ECG) Guided Peripherally Inserted Central Catheter Tip Placement among Neonates

    Science.gov (United States)

    Zhou, Lian-juan; Xua, Hong-zhen; Xu, Mei-fang; Hu, Yan; Lou, Xiao-Fang

    2017-01-01

    Abstract Objective To explore the clinical application of the intracavitary electrocardiogram (IC-ECG) guided Peripherally Inserted Central Catheter (PICC) tip placement among neonates. Background the ECGs of neonates are difficult to perform and their wave shapes are of doubtful accuracy due to various interfering factors Method 115 neonates were admitted to perform PICC guided by IC-ECG. Logistic regression was performed to analyze all possible influencing factors of the accuracy from the tip placement. The puncture site of the PICC, gestational age, height, weight, basal P/R amplitude and positioning P/R amplitude might be related to the accuracy of IC-ECG location. Result The accuracy in the lower extremity was higher than that in the upper extremity. Multivariate logistic regression analysis showed that the weight (Odds Ratio (OR)=1.93, 95%Confidence Interval(CI):1.06-3.50) and positioning P/R amplitude (OR=32.33, 95%CI: 2.02-517.41) are statistically significant risks to the accuracy PICC tip placement. Conclusions Possible methods to improve the accuracy might be Catheterizing through lower extremity, keeping the neonates calm, enhancing the electrocardiogram signal and strengthening technical training. Therefore it is practical to perfrom a tip placement by the dynamic change in the P waves from an electrocardiogram (ECG) guided PICC among neonates and as reliable as using X-rays. PMID:28730171

  16. Using the Surface ECG to Identify Right Ventricular Pacing Lead Position: A Cautionary Tale.

    Science.gov (United States)

    Kaye, Gerald C; Rowe, Matthew K; Gould, Paul A

    2017-09-01

    Chronic right ventricular (RV) apical pacing may lead to the development of heart failure in some patients. Although pacing of the RV septum has been proposed as an alternative, positioning a lead in the true septum has proven challenging. In addition to fluoroscopy at implant, it has been suggested that 12-lead surface electrocardiogram (ECG) can be used to determine septal lead position; however, studies show this may be inaccurate. We present a case where a change in the ECG QRS axis late after pacemaker insertion with an active fixation lead highlights the difficulties of ECG localization of pacing leads. © 2017 Wiley Periodicals, Inc.

  17. What adult electrocardiogram (ECG) diagnoses and/or findings do residents in emergency medicine need to know?

    Science.gov (United States)

    Patocka, Catherine; Turner, Joel; Wiseman, Jeffrey

    2015-11-01

    There is no evidence-based description of electrocardiogram (ECG) interpretation competencies for emergency medicine (EM) trainees. The first step in defining these competencies is to develop a prioritized list of adult ECG findings relevant to EM contexts. The purpose of this study was to categorize the importance of various adult ECG diagnoses and/or findings for the EM trainee. We developed a list of potentially important adult ECG diagnoses/findings and conducted a Delphi opinion-soliciting process. Participants used a 4-point Likert scale to rate the importance of each diagnosis for EM trainees. Consensus was defined as a minimum of 75% agreement at the second round or later. In the absence of consensus, stability was defined as a shift of 20% or less after successive rounds. A purposive sampling of 22 emergency physicians participated in the Delphi process, and 16 (72%) completed the process. Of those, 15 were from 11 different EM training programs across Canada and one was an expert in EM electrocardiography. Overall, 78 diagnoses reached consensus, 42 achieved stability and one diagnosis achieved neither consensus nor stability. Out of 121 potentially important adult ECG diagnoses, 53 (44%) were considered "must know" diagnoses, 61 (50%) "should know" diagnoses, and 7 (6%) "nice to know" diagnoses. We have categorized adult ECG diagnoses within an EM training context, knowledge of which may allow clinical EM teachers to establish educational priorities. This categorization will also facilitate the development of an educational framework to establish EM trainee competency in ECG interpretation.

  18. [Surface ECG characteristics of right and left atrial flutter].

    Science.gov (United States)

    Rostock, Thomas; Konrad, Torsten; Sonnenschein, Sebastian; Mollnau, Hanke; Ocete, Blanca Quesada; Bock, Karsten; Spittler, Raphael; Huber, Carola; Theis, Cathrin

    2015-09-01

    Atrial tachycardia in virtually all areas of both atria has become more important in the clinical management of patients with previous complex atrial fibrillation ablation. Accurate interpretation of surface electrocardiogram (ECG) characteristics is of paramount importance to localize the origin of atrial tachycardia, particularly for planning interventional treatment. This article highlights the ECG features of different types of right and left atrial tachycardia. Typical right atrial flutter through the cavotricuspid isthmus conducts septally in a cranial direction and demonstrates sawtooth-like flutter waves which start negative in II, III and aVF and then show a steep slope upwards to the isoelectric line. The flutter rate typically ranges between 240-250 beats/min. In contrast, right atrial flutter in a clockwise rotation, flutter around the vena cava inferior or superior and around a scar (e.g. after cardiac surgery) show positive or biphasic flutter waves (lower or upper loop reentry). Left atrial flutter waves (e.g. around the mitral valve or around the pulmonary veins) are very heterogeneous and are typically positive in V1 as the left atrium is located in the posterior mediastinum. Specific knowledge of flutter wave morphology in surface ECG facilitates planning and performance of the ablation strategy.

  19. Wavelet-based unsupervised learning method for electrocardiogram suppression in surface electromyograms.

    Science.gov (United States)

    Niegowski, Maciej; Zivanovic, Miroslav

    2016-03-01

    We present a novel approach aimed at removing electrocardiogram (ECG) perturbation from single-channel surface electromyogram (EMG) recordings by means of unsupervised learning of wavelet-based intensity images. The general idea is to combine the suitability of certain wavelet decomposition bases which provide sparse electrocardiogram time-frequency representations, with the capacity of non-negative matrix factorization (NMF) for extracting patterns from images. In order to overcome convergence problems which often arise in NMF-related applications, we design a novel robust initialization strategy which ensures proper signal decomposition in a wide range of ECG contamination levels. Moreover, the method can be readily used because no a priori knowledge or parameter adjustment is needed. The proposed method was evaluated on real surface EMG signals against two state-of-the-art unsupervised learning algorithms and a singular spectrum analysis based method. The results, expressed in terms of high-to-low energy ratio, normalized median frequency, spectral power difference and normalized average rectified value, suggest that the proposed method enables better ECG-EMG separation quality than the reference methods. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  20. Use of the Surface Electrocardiogram to Define the Nature of Challenging Arrhythmias.

    Science.gov (United States)

    Singh, David K; Peter, C Thomas

    2016-03-01

    Despite unprecedented advances in technology, the electrocardiogram (ECG) remains essential to the practice of modern electrophysiology. Since its emergence at the turn of the nineteenth century, the form of the ECG has changed little. What has changed is our ability to understand the complex mechanisms that underlie various arrhythmias. In this article, the authors review several important principles of ECG interpretation by providing illustrative tracings. The authors also highlight several important concepts that be can used in ECG analysis. There are several fundamental principles that should be considered in ECG interpretation. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. [The surface ECG in the diagnosis of cardiac arrhythmias: the value of the right precordial leads].

    Science.gov (United States)

    Richter, S

    2007-03-01

    The surface electrocardiogram (ECG) is a simple noninvasive method to assess the electrical activity of the heart and provides important information to identify patients with cardiac arrhythmias and increased arrhythmic risk. This brief review highlights cardiac conditions in which the right precordial leads recorded on the surface ECG during sinus rhythm or tachycardia are of important diagnostic and prognostic value. Epsilon waves seen in the right precordial ST segments are the electrocardiographic hallmark of arrhythmogenic right ventricular cardiomyopathy. The diagnosis of Brugada syndrome and risk stratification of affected patients are based on a coved-type >or=2 mm ST-segment elevation in the right precordial leads. This typical ECG pattern may be present persistently, intermittently or only after administration of sodium-channel blockers. The early repolarization syndrome, most commonly seen in healthy young individuals, is characterized by a ST-segment elevation of 1 to 4 mm in the mid-precordial leads with a notched and elevated J point in lead V4. The precordial ECG T-wave repolarization pattern may be helpful in identifying the genotype in patients with suspected long QT syndrome. In patients with overt preexcitation, the surface leads V1 and V2 play a key role in localizing the site of bypass-tract insertion. Finally, the right precordial lead V1 is often crucial in the diagnosis of narrow and broad QRS-complex tachycardias.

  2. Utility of the surface electrocardiogram for confirming right ventricular septal pacing: validation using electroanatomical mapping.

    Science.gov (United States)

    Burri, Haran; Park, Chan-Il; Zimmermann, Marc; Gentil-Baron, Pascale; Stettler, Carine; Sunthorn, Henri; Domenichini, Giulia; Shah, Dipen

    2011-01-01

    When targeting the interventricular septum during pacemaker implantation, the lead may inadvertently be positioned on the anterior wall due to imprecise fluoroscopic landmarks. Surface electrocardiogram (ECG) criteria of the paced QRS complex (e.g. negativity in lead I) have been proposed to confirm a septal position, but these criteria have not been properly validated. Our aim was to investigate whether the paced QRS complex may be used to confirm septal lead position. Anatomical reconstruction of the right ventricle was performed using a NavX® system in 31 patients (70 ± 11 years, 26 males) to validate pacing sites. Surface 12-lead ECGs were analysed by digital callipers and compared while pacing from a para-Hissian position, from the mid-septum, and from the anterior free wall. Duration of the QRS complex was not significantly shorter when pacing from the mid-septum compared with the other sites. QRS axis was significantly less vertical during mid-septal pacing (18 ± 51°) compared with para-Hissian (38 ± 37°, P = 0.028) and anterior (53 ± 55°, P = 0.003) pacing, and QRS transition was intermediate (4.8 ± 1.3 vs. 3.8 ± 1.3, P < 0.001, and vs. 5.4 ± 0.9, P = 0.045, respectively), although no cut-offs could reliably distinguish sites. A negative QRS or the presence of a q-wave in lead I tended to be more frequent with anterior than with mid-septal pacing (9/31 vs. 3/31, P = 0.2 and 8/31 vs. 1/31, P = 1.0, respectively). No single ECG criterion could reliably distinguish pacing the mid-septum from the anterior wall. In particular, a negative QRS complex in lead I is an inaccurate criterion for validating septal pacing.

  3. Surface ECG and Fluoroscopy are Not Predictive of Right Ventricular Septal Lead Position Compared to Cardiac CT.

    Science.gov (United States)

    Rowe, Matthew K; Moore, Peter; Pratap, Jit; Coucher, John; Gould, Paul A; Kaye, Gerald C

    2017-05-01

    Controversy exists regarding the optimal lead position for chronic right ventricular (RV) pacing. Placing a lead at the RV septum relies upon fluoroscopy assisted by a surface 12-lead electrocardiogram (ECG). We compared the postimplant lead position determined by ECG-gated multidetector contrast-enhanced computed tomography (MDCT) with the position derived from the surface 12-lead ECG. Eighteen patients with permanent RV leads were prospectively enrolled. Leads were placed in the RV septum (RVS) in 10 and the RV apex (RVA) in eight using fluoroscopy with anteroposterior and left anterior oblique 30° views. All patients underwent MDCT imaging and paced ECG analysis. ECG criteria were: QRS duration; QRS axis; positive or negative net QRS amplitude in leads I, aVL, V1, and V6; presence of notching in the inferior leads; and transition point in precordial leads at or after V4. Of the 10 leads implanted in the RVS, computed tomography (CT) imaging revealed seven to be at the anterior RV wall, two at the anteroseptal junction, and one in the true septum. For the eight RVA leads, four were anterior, two septal, and two anteroseptal. All leads implanted in the RVS met at least one ECG criteria (median 3, range 1-6). However, no criteria were specific for septal position as judged by MDCT. Mean QRS duration was 160 ± 24 ms in the RVS group compared with 168 ± 14 ms for RVA pacing (P = 0.38). We conclude that the surface ECG is not sufficiently accurate to determine RV septal lead tip position compared to cardiac CT. © 2017 Wiley Periodicals, Inc.

  4. REPEATED TREATMENTS WITH DOXORUBICIN CAUSES ELECTROCARDIOGRAM (ECG) CHANGES AND INCREASED VENTRICULAR PREMATURE BEATS IN WISTAR-KYOTO (WKY) RATS

    Science.gov (United States)

    Doxorubicin (DOX) is a widely used anthracycline anti-neoplastic drug used to treat tumors. However it has been implicated in irreversible cardiac toxicity via the generation of a proxidant semiquinone free radical, which often results in cardiomyopathy and changes in the ECG. Ac...

  5. Software design for analysis of multichannel intracardial and body surface electrocardiograms

    NARCIS (Netherlands)

    Potse, Mark; Linnenbank, André C.; Grimbergen, Cornelis A.

    2002-01-01

    Analysis of multichannel ECG recordings (body surface maps (BSMs) and intracardial maps) requires special software. We created a software package and a user interface on top of a commercial data analysis package (MATLAB) by a combination of high-level and low-level programming. Our software was

  6. Localization of accessory pathway in patients with wolff-parkinson-white syndrome from surface ecg using arruda algorithm

    International Nuclear Information System (INIS)

    Saidullah, S.; Shah, B.

    2016-01-01

    Background: To ablate accessory pathway successfully and conveniently, accurate localization of the pathway is needed. Electrophysiologists use different algorithms before taking the patients to the electrophysiology (EP) laboratory to plan the intervention accordingly. In this study, we used Arruda algorithm to locate the accessory pathway. The objective of the study was to determine the accuracy of the Arruda algorithm for locating the pathway on surface ECG. Methods: It was a cross-sectional observational study conducted from January 2014 to January 2016 in the electrophysiology department of Hayat Abad Medical Complex Peshawar Pakistan. A total of fifty nine (n=59) consecutive patients of both genders between age 14-60 years presented with WPW syndrome (Symptomatic tachycardia with delta wave on surface ECG) were included in the study. Patient's electrocardiogram (ECG) before taking patients to laboratory was analysed on Arruda algorithm. Standard four wires protocol was used for EP study before ablation. Once the findings were confirmed the pathway was ablated as per standard guidelines. Results: A total of fifty nine (n=59) patients between the age 14-60 years were included in the study. Cumulative mean age was 31.5 years ± 12.5 SD. There were 56.4% (n=31) males with mean age 28.2 years ± 10.2 SD and 43.6% (n=24) were females with mean age 35.9 years ± 14.0 SD. Arruda algorithm was found to be accurate in predicting the exact accessory pathway (AP) in 83.6% (n=46) cases. Among all inaccurate predictions (n=9), Arruda inaccurately predicted two third (n=6; 66.7%) pathways towards right side (right posteroseptal, right posterolateral and right antrolateral). Conclusion: Arruda algorithm was found highly accurate in predicting accessory pathway before ablation. (author)

  7. Non-Invasive Fetal Monitoring: A Maternal Surface ECG Electrode Placement-Based Novel Approach for Optimization of Adaptive Filter Control Parameters Using the LMS and RLS Algorithms.

    Science.gov (United States)

    Martinek, Radek; Kahankova, Radana; Nazeran, Homer; Konecny, Jaromir; Jezewski, Janusz; Janku, Petr; Bilik, Petr; Zidek, Jan; Nedoma, Jan; Fajkus, Marcel

    2017-05-19

    This paper is focused on the design, implementation and verification of a novel method for the optimization of the control parameters (such as step size μ and filter order N ) of LMS and RLS adaptive filters used for noninvasive fetal monitoring. The optimization algorithm is driven by considering the ECG electrode positions on the maternal body surface in improving the performance of these adaptive filters. The main criterion for optimal parameter selection was the Signal-to-Noise Ratio (SNR). We conducted experiments using signals supplied by the latest version of our LabVIEW-Based Multi-Channel Non-Invasive Abdominal Maternal-Fetal Electrocardiogram Signal Generator, which provides the flexibility and capability of modeling the principal distribution of maternal/fetal ECGs in the human body. Our novel algorithm enabled us to find the optimal settings of the adaptive filters based on maternal surface ECG electrode placements. The experimental results further confirmed the theoretical assumption that the optimal settings of these adaptive filters are dependent on the ECG electrode positions on the maternal body, and therefore, we were able to achieve far better results than without the use of optimization. These improvements in turn could lead to a more accurate detection of fetal hypoxia. Consequently, our approach could offer the potential to be used in clinical practice to establish recommendations for standard electrode placement and find the optimal adaptive filter settings for extracting high quality fetal ECG signals for further processing. Ultimately, diagnostic-grade fetal ECG signals would ensure the reliable detection of fetal hypoxia.

  8. Play the Electrocardiogram Game

    Science.gov (United States)

    ... Related Blood Typing Control of the Cell Cycle Diabetes and Insulin DNA - RNA - Protein DNA - the Double Helix Ear Pages ECG/Electrocardiogram Immune System Immune Responses Malaria MRI Nerve Signaling Pavlov's Dog Split Brain Experiments The Cell and its Organelles ...

  9. Arrhythmia Identification with Two-Lead Electrocardiograms Using Artificial Neural Networks and Support Vector Machines for a Portable ECG Monitor System

    Directory of Open Access Journals (Sweden)

    Shing-Hong Liu

    2013-01-01

    Full Text Available An automatic configuration that can detect the position of R-waves, classify the normal sinus rhythm (NSR and other four arrhythmic types from the continuous ECG signals obtained from the MIT-BIH arrhythmia database is proposed. In this configuration, a support vector machine (SVM was used to detect and mark the ECG heartbeats with raw signals and differential signals of a lead ECG. An algorithm based on the extracted markers segments waveforms of Lead II and V1 of the ECG as the pattern classification features. A self-constructing neural fuzzy inference network (SoNFIN was used to classify NSR and four arrhythmia types, including premature ventricular contraction (PVC, premature atrium contraction (PAC, left bundle branch block (LBBB, and right bundle branch block (RBBB. In a real scenario, the classification results show the accuracy achieved is 96.4%. This performance is suitable for a portable ECG monitor system for home care purposes.

  10. [Advances of portable electrocardiogram monitor design].

    Science.gov (United States)

    Ding, Shenping; Wang, Yinghai; Wu, Weirong; Deng, Lingli; Lu, Jidong

    2014-06-01

    Portable electrocardiogram monitor is an important equipment in the clinical diagnosis of cardiovascular diseases due to its portable, real-time features. It has a broad application and development prospects in China. In the present review, previous researches on the portable electrocardiogram monitors have been arranged, analyzed and summarized. According to the characteristics of the electrocardiogram (ECG), this paper discusses the ergonomic design of the portable electrocardiogram monitor, including hardware and software. The circuit components and software modules were parsed from the ECG features and system functions. Finally, the development trend and reference are provided for the portable electrocardiogram monitors and for the subsequent research and product design.

  11. Knowledge and Utilization of Electrocardiogram among Resident ...

    African Journals Online (AJOL)

    Background: Electrocardiogram (ECG) is a simple, readily affordable, and noninvasive tool for the evaluation of cardiac disorders. There is a dearth of information on the utility of ECG in general practice in Nigeria. We assessed the knowledge and utilization of ECG among family medicine residents in Nigeria. Materials and ...

  12. Interpretation of the Electrocardiogram in Athletes.

    Science.gov (United States)

    Prakash, Keerthi; Sharma, Sanjay

    2016-04-01

    Regular intensive participation in sport results in electrical and structural alterations within the heart that can manifest on the surface electrocardiogram (ECG). In addition to the actual sporting discipline and the volume and intensity of exercise being performed, other factors play a role in the development of certain ECG patterns including sex, age, and ethnicity. In some instances, large male endurance athletes and those of African or Afro-Caribbean origin (black athletes), might exhibit ECG patterns that overlap with those seen in patients with cardiomyopathy and channelopathies, which are recognized causes of exercise-related sudden cardiac death. The ability to distinguish accurately between benign physiological electrical alterations and pathological ECG changes is crucial to prevent the unnecessary termination of an athlete's career and to minimize the risk of sudden death. Several recommendations currently exist to aid the physician in the interpretation of the athlete's ECG. In this review we discuss which ECG patterns can safely be considered benign as opposed to those that should prompt the physician to consider cardiac pathology. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  13. QRS duration and QRS fractionation on surface electrocardiogram are markers of right ventricular dysfunction and atrialization in patients with Ebstein anomaly.

    Science.gov (United States)

    Egidy Assenza, Gabriele; Valente, Anne Marie; Geva, Tal; Graham, Dionne; Pluchinotta, Francesca Romana; Romana Pluchinotta, Francesca; Sanders, Stephen P; Autore, Camillo; Volpe, Massimo; Landzberg, Michael J; Cecchin, Frank

    2013-01-01

    Ebstein anomaly is a rare and heterogeneous congenital heart defect affecting the tricuspid valve and right ventricular (RV) myocardium. Few studies have analysed the electrocardiographic features of Ebstein anomaly and none has addressed correlations with disease severity. Patients with Ebstein anomaly who had undergone electrocardiography and cardiac magnetic resonance (CMR) within 6 weeks between 2001 and 2009 were included. Exclusion criteria were: associated congenital cardiac defect, previous RV myoplasty and/or reduction surgery, class I anti-arrhythmic drug therapy, and paced/pre-excited QRS. Standard electrocardiogram (ECG) findings were correlated with CMR-based RV measures and clinical profile. The mean age of the 63 study patients was 22 ± 13 years. An RV conduction delay (rsR' pattern in right precordial leads) was present in 45 patients (71%). The QRS duration correlated with anatomic RV diastolic volume (r = +0.56, P surface ECG identifies a subset of patients with Ebstein anomaly with mild morphological and functional abnormalities and better clinical profile.

  14. Reconstruction of an 8-lead surface ECG from two subcutaneous ICD vectors.

    Science.gov (United States)

    Wilson, David G; Cronbach, Peter L; Panfilo, D; Greenhut, Saul E; Stegemann, Berthold P; Morgan, John M

    2017-06-01

    Techniques exist which allow surface ECGs to be reconstructed from reduced lead sets. We aimed to reconstruct an 8-lead ECG from two independent S-ICD sensing electrodes vectors as proof of this principle. Participants with ICDs (N=61) underwent 3minute ECGs using a TMSi Porti7 multi-channel signal recorder (TMS international, The Netherlands) with electrodes in the standard S-ICD and 12-lead positions. Participants were randomised to either a training (N=31) or validation (N=30) group. The transformation used was a linear combination of the 2 independent S-ICD vectors to each of the 8 independent leads of the 12-lead ECG, with coefficients selected that minimized the root mean square error (RMSE) between recorded and derived ECGs when applied to the training group. The transformation was then applied to the validation group and agreement between the recorded and derived lead pairs was measured by Pearson correlation coefficient (r) and normalised RMSE (NRMSE). In total, 27 patients with complete data sets were included in the validation set consisting of 57,888 data points from 216 full lead sets. The distribution of the r and NRMSE were skewed. Mean r=0.770 (SE 0.024), median r=0.925. NRMSE mean=0.233 (SE 0.015) median=0.171. We have demonstrated that the reconstruction of an 8-lead ECG from two S-ICD vectors is possible. If perfected, the ability to generate accurate multi-lead surface ECG data from an S-ICD would potentially allow recording and review of clinical arrhythmias at follow-up. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. The acquisition and retention of ECG interpretation skills after a standardized web-based ECG tutorial

    DEFF Research Database (Denmark)

    Rolskov Bojsen, Signe; Räder, Sune Bernd Emil Werner; Holst, Anders Gaardsdal

    2015-01-01

    BACKGROUND: Electrocardiogram (ECG) interpretation is of great importance for patient management. However, medical students frequently lack proficiency in ECG interpretation and rate their ECG training as inadequate. Our aim was to examine the effect of a standalone web-based ECG tutorial...

  16. WaveformECG: A Platform for Visualizing, Annotating, and Analyzing ECG Data.

    Science.gov (United States)

    Winslow, Raimond L; Granite, Stephen; Jurado, Christian

    2016-01-01

    The electrocardiogram (ECG) is the most commonly collected data in cardiovascular research because of the ease with which it can be measured and because changes in ECG waveforms reflect underlying aspects of heart disease. Accessed through a browser, WaveformECG is an open source platform supporting interactive analysis, visualization, and annotation of ECGs.

  17. Flexible Capacitive Electrodes for Minimizing Motion Artifacts in Ambulatory Electrocardiograms

    Directory of Open Access Journals (Sweden)

    Jeong Su Lee

    2014-08-01

    Full Text Available This study proposes the use of flexible capacitive electrodes for reducing motion artifacts in a wearable electrocardiogram (ECG device. The capacitive electrodes have conductive foam on their surface, a shield, an optimal input bias resistor, and guarding feedback. The electrodes are integrated in a chest belt, and the acquired signals are transmitted wirelessly for ambulatory heart rate monitoring. We experimentally validated the electrode performance with subjects standing and walking on a treadmill at speeds of up to 7 km/h. The results confirmed the highly accurate heart rate detection capacity of the developed system and its feasibility for daily-life ECG monitoring.

  18. Evaluation of an electrocardiogram on QR code.

    Science.gov (United States)

    Nakayama, Masaharu; Shimokawa, Hiroaki

    2013-01-01

    An electrocardiogram (ECG) is an indispensable tool to diagnose cardiac diseases, such as ischemic heart disease, myocarditis, arrhythmia, and cardiomyopathy. Since ECG patterns vary depend on patient status, it is also used to monitor patients during treatment and comparison with ECGs with previous results is important for accurate diagnosis. However, the comparison requires connection to ECG data server in a hospital and the availability of data connection among hospitals is limited. To improve the portability and availability of ECG data regardless of server connection, we here introduce conversion of ECG data into 2D barcodes as text data and decode of the QR code for drawing ECG with Google Chart API. Fourteen cardiologists and six general physicians evaluated the system using iPhone and iPad. Overall, they were satisfied with the system in usability and accuracy of decoded ECG compared to the original ECG. This new coding system may be useful in utilizing ECG data irrespective of server connections.

  19. Effective Electrocardiogram Steganography Based on Coefficient Alignment.

    Science.gov (United States)

    Yang, Ching-Yu; Wang, Wen-Fong

    2016-03-01

    This study presents two types of data hiding methods based on coefficient alignment for electrocardiogram (ECG) signals, namely, lossy and reversible ECG steganographys. The lossy method is divided into high-quality and high-capacity ECG steganography, both of which are capable of hiding confidential patient data in ECG signals. The reversible data hiding method can not only hide secret messages but also completely restore the original ECG signal after bit extraction. Simulations confirmed that the perceived quality generated by the lossy ECG steganography methods was good, while hiding capacity was acceptable. In addition, these methods have a certain degree of robustness, which is rare in conventional ECG stegangraphy schemes. Moreover, the proposed reversible ECG steganography method can not only successfully extract hidden messages but also completely recover the original ECG data.

  20. Application of Wavelet Entropy to Predict Atrial Fibrillation Progression from the Surface ECG

    Directory of Open Access Journals (Sweden)

    Raúl Alcaraz

    2012-01-01

    Full Text Available Atrial fibrillation (AF is the most common supraventricular arrhythmia in clinical practice, thus, being the subject of intensive research both in medicine and engineering. Wavelet Entropy (WE is a measure of the disorder degree of a specific phenomena in both time and frequency domains, allowing to reveal underlying dynamical processes out of sight for other methods. The present work introduces two different WE applications to the electrocardiogram (ECG of patients in AF. The first application predicts the spontaneous termination of paroxysmal AF (PAF, whereas the second one deals with the electrical cardioversion (ECV outcome in persistent AF patients. In both applications, WE was used with the objective of assessing the atrial fibrillatory (f waves organization. Structural changes into the f waves reflect the atrial activity organization variation, and this fact can be used to predict AF progression. To this respect, results in the prediction of PAF termination regarding sensitivity, specificity, and accuracy were 95.38%, 91.67%, and 93.60%, respectively. On the other hand, for ECV outcome prediction, 85.24% sensitivity, 81.82% specificity, and 84.05% accuracy were obtained. These results turn WE as the highest single predictor of spontaneous PAF termination and ECV outcome, thus being a promising tool to characterize non-invasive AF signals.

  1. Dry Electrode Harness System For Wireless 12-LEAD ECG

    Data.gov (United States)

    National Aeronautics and Space Administration — Human spaceflight requires the ability to obtain diagnostic quality 12-lead electrocardiograms (ECGs). Current systems require significant upmass, volume, and crew...

  2. Electrocardiographic intricacies clarified by echocardiography--should the electrocardiogram be interpreted echocardiographically?

    Science.gov (United States)

    Ker, James

    2012-07-12

    During the past century the electrocardiogram (ECG) has established itself as an integral part of the cardiovascular examination. Since the first direct recordings of cardiac potentials by Waller in 1887, to the invention of the string galvanometer by Willem Einthoven in 1901, to use in the clinic by 1910, the electrocardiogram has become the most widely used clinical tool in the diagnosis of virtually every type of heart disease. Currently up to 20 million ECGs are performed annually in the United States alone. However, in this era of readily available echocardiography, an important caveat in the interpretation of the electrocardiogram has emerged: variants of intracardiac structures which might mimic disease on the ECG. In this perspective various structural variants of intracardiac structures, specifically variants of papillary muscles and subaortic muscular bands, will be shown, together with their associated electrocardiographic changes, mimicking disease. It is concluded that in this era of readily available echocardiography, the electrocardiogram should be interpreted echocardiographically in instances where intricate variations are seen on the surface electrocardiogram. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  3. The prevalence and relevance of the Brugada-type electrocardiogram in the Danish general population: data from the Copenhagen City Heart Study

    DEFF Research Database (Denmark)

    Pecini, Redi; Cedergreen, Pernille Kallerup; Theilade, Simone

    2010-01-01

    The prevalence of the Brugada-type electrocardiogram (ECG) in the Danish population is not known.......The prevalence of the Brugada-type electrocardiogram (ECG) in the Danish population is not known....

  4. Prevalence and associated factors of resting electrocardiogram abnormalities among systemic lupus erythematosus patients without cardiovascular disease

    OpenAIRE

    Al Rayes, Hanan; Harvey, Paula J.; Gladman, Dafna D.; Su, Jiandong; Sabapathy, Arthy; Urowitz, Murray B.; Touma, Zahi

    2017-01-01

    Background Electrocardiogram (ECG) cardiovascular disease (CVD) abnormalities (ECG-CVD) are predictive of subsequent CVD events in the general population. Systemic lupus erythematosus (SLE) patients are vulnerable to CVD. We aimed to determine the prevalence of ECG-CVD in SLE patients and to examine the risk factors associated with ECG-CVD. Methods A 12-lead resting supine ECG was performed on consecutive adult patients attending the clinic. One cardiologist interpreted the ECGs. ECG-CVD were...

  5. A novel noninvasive surface ECG analysis using interlead QRS dispersion in arrhythmogenic right ventricular cardiomyopathy.

    Science.gov (United States)

    Hsieh, Wan-Hsin; Lin, Chin-Yu; Te, Abigail Louise D; Lo, Men-Tzung; Wu, Cheng-I; Chung, Fa-Po; Chang, Yi-Chung; Chang, Shih-Lin; Lin, Chen; Lo, Li-Wei; Hu, Yu-Feng; Liao, Jo-Nan; Chen, Yun-Yu; Jhuo, Shih-Jie; Raharjo, Sunu Budhi; Lin, Yenn-Jiang; Chen, Shih-Ann

    2017-01-01

    This study investigated the feasibility of using the precordial surface ECG lead interlead QRS dispersion (IQRSD) in the identification of abnormal ventricular substrate in arrhythmogenic right ventricular cardiomyopathy (ARVC). Seventy-one consecutive patients were enrolled and reclassified into 4 groups: definite ARVC with epicardial ablation (Group 1), ARVC with ventricular tachycardia (VT, Group 2), idiopathic right ventricular outflow tract VT without ARVC (Group 3), and controls without VT (Group 4). IQRSD was quantified by the angular difference between the reconstruction vectors obtained from the QRS-loop decomposition, based on a principal component analysis (PCA). Electroanatomic mapping and simulated ECGs were used to investigate the relationship between QRS dispersion and abnormal substrate. The percentage of the QRS loop area in the Group 1-2 was smaller than the controls (P = 0.01). The IQRSD between V1-V2 could differentiate all VTs from control (Psurface ECG precordial leads successfully differentiated ARVC from controls, and could be used as a noninvasive marker to identify the abnormal substrate and the status of ARVC patients who can benefit from epicardial ablation.

  6. Arm and wrist surface potential mapping for wearable ECG rhythm recording devices: a pilot clinical study

    Science.gov (United States)

    Lynn, W. D.; Escalona, O. J.; McEneaney, D. J.

    2013-06-01

    This study addresses an important question in the development of a ECG device that enables long term monitoring of cardiac rhythm. This device would utilise edge sensor technologies for dry, non-irritant skin contact suitable for distal limb application and would be supported by embedded ECG denoising processes. Contemporary ECG databases including those provided by MIT-BIH and Physionet are focused on interpretation of cardiac disease and rhythm tracking. The data is recorded using chest leads as in standard clinical practise. For the development of a peripherally located heart rhythm monitor, such data would be of limited use. To provide a useful database adequate for the development of the above mentioned cardiac monitoring device a unipolar body surface potential map from the left arm and wrist was gathered in 37 volunteer patients and characterized in this study. For this, the reference electrode was placed at the wrist. Bipolar far-field electrogram leads were derived and analysed. Factors such as skin variability, 50Hz noise interference, electrode contact noise, motion artifacts and electromyographic noise, presented a challenge. The objective was quantify the signal-to-noise ratio (SNR) at the far-field locations. Preliminary results reveal that an electrogram indicative of the QRS complex can be recorded on the distal portion of the left arm when denoised using signal averaging techniques.

  7. A Portable ECG Recorder for Shipboard Use

    National Research Council Canada - National Science Library

    Ryack, Bernard L

    1989-01-01

    ...) that would serve as a medical consultant to the Independent Duty Corpsman. The system was designed for use on submarines where such common tools as x-rays and electrocardiograms (ECGs) are not available...

  8. Surface ECG interatrial block-guided treatment for stroke prevention: rationale for an attractive hypothesis.

    Science.gov (United States)

    Bayés de Luna, Antoni; Martínez-Sellés, Manuel; Bayés-Genís, Antoni; Elosua, Roberto; Baranchuk, Adrian

    2017-07-31

    Atrial fibrillation (AF) is the most common sustained arrhythmia and is associated with stroke, cognitive impairment, and cardiovascular death. Some predisposing factors - as aging, diabetes, hypertension - induce and maintain electrophysiological and ultrastructural remodeling that usually includes fibrosis. Interatrial conduction disturbances play a crucial role in the initiation of atrial fibrosis and in its associated complications. The diagnosis of interatrial blocks (IABs) is easy to perform using the surface ECG. IAB is classified as partial when the P wave duration is ≥120 ms, and advanced if the P wave also presents a biphasic pattern in II, III and aVF. IAB is very frequent in the elderly and, particularly in the case of the advanced type, is associated with AF, AF recurrences, stroke, and dementia. The anticoagulation in elderly patients at high risk of AF without documented arrhythmias is an open issue but recent data suggest that it might have a role, particularly in elderly patients with structural heart disease, high CHA 2 DS 2 VASc (Congestive heart failure/left ventricular dysfunction, Hypertension, Age ≥ 75 [doubled], Diabetes, Stroke [doubled] - Vascular disease, Age 65-74, and Sex category [female]), and advanced IAB. In this debate, we discuss the association of surface ECG IAB, a marker of atrial fibrosis, with AF and stroke. We also present the rationale that justifies further studies regarding anticoagulation in some of these patients.

  9. ECG artifact cancellation in surface EMG signals by fractional order calculus application.

    Science.gov (United States)

    Miljković, Nadica; Popović, Nenad; Djordjević, Olivera; Konstantinović, Ljubica; Šekara, Tomislav B

    2017-03-01

    New aspects for automatic electrocardiography artifact removal from surface electromyography signals by application of fractional order calculus in combination with linear and nonlinear moving window filters are explored. Surface electromyography recordings of skeletal trunk muscles are commonly contaminated with spike shaped artifacts. This artifact originates from electrical heart activity, recorded by electrocardiography, commonly present in the surface electromyography signals recorded in heart proximity. For appropriate assessment of neuromuscular changes by means of surface electromyography, application of a proper filtering technique of electrocardiography artifact is crucial. A novel method for automatic artifact cancellation in surface electromyography signals by applying fractional order calculus and nonlinear median filter is introduced. The proposed method is compared with the linear moving average filter, with and without prior application of fractional order calculus. 3D graphs for assessment of window lengths of the filters, crest factors, root mean square differences, and fractional calculus orders (called WFC and WRC graphs) have been introduced. For an appropriate quantitative filtering evaluation, the synthetic electrocardiography signal and analogous semi-synthetic dataset have been generated. The examples of noise removal in 10 able-bodied subjects and in one patient with muscle dystrophy are presented for qualitative analysis. The crest factors, correlation coefficients, and root mean square differences of the recorded and semi-synthetic electromyography datasets showed that the most successful method was the median filter in combination with fractional order calculus of the order 0.9. Statistically more significant (p ECG peak reduction was obtained by the median filter application compared to the moving average filter in the cases of low level amplitude of muscle contraction compared to ECG spikes. The presented results suggest that the

  10. The prediction of the in-hospital mortality of acutely ill medical patients by electrocardiogram (ECG) dispersion mapping compared with established risk factors and predictive scores--a pilot study.

    LENUS (Irish Health Repository)

    Kellett, John

    2011-08-01

    ECG dispersion mapping (ECG-DM) is a novel technique that analyzes low amplitude ECG oscillations and reports them as the myocardial micro-alternation index (MMI). This study compared the ability of ECG-DM to predict in-hospital mortality with traditional risk factors such as age, vital signs and co-morbid diagnoses, as well as three predictive scores: the Simple Clinical Score (SCS)--based on clinical and ECG findings, and two Medical Admission Risk System scores--one based on vital signs and laboratory data (MARS), and one only on laboratory data (LD).

  11. Removing ECG Artifact from the Surface EMG Signal Using Adaptive Subtraction Technique

    Science.gov (United States)

    Abbaspour, S; Fallah, A

    2014-01-01

    Background: The electrocardiogram artifact is a major contamination in the electromyogram signals when electromyogram signal is recorded from upper trunk muscles and because of that the contaminated electromyogram is not useful. Objective: Removing electrocardiogram contamination from electromyogram signals. Methods: In this paper, the clean electromyogram signal, electrocardiogram artifact and electrocardiogram signal were recorded from leg muscles, the pectoralis major muscle of the left side and V4, respectively. After the pre-processing, contaminated electromyogram signal is simulated with a combination of clean electromyogram and electrocardiogram artifact. Then, contaminated electromyogram is cleaned using adaptive subtraction method. This method contains some steps; (1) QRS detection, (2) formation of electrocardiogram template by averaging the electrocardiogram complexes, (3) using low pass filter to remove undesirable artifacts, (4) subtraction. Results: Performance of our method is evaluated using qualitative criteria, power spectrum density and coherence and quantitative criteria signal to noise ratio, relative error and cross correlation. The result of signal to noise ratio, relative error and cross correlation is equal to 10.493, 0.04 and %97 respectively. Finally, there is a comparison between proposed method and some existing methods. Conclusion: The result indicates that adaptive subtraction method is somewhat effective to remove electrocardiogram artifact from contaminated electromyogram signal and has an acceptable result. PMID:25505766

  12. ECG De-noising

    DEFF Research Database (Denmark)

    Kærgaard, Kevin; Jensen, Søren Hjøllund; Puthusserypady, Sadasivan

    2015-01-01

    proposes two adaptive techniques, namely the EEMD-BLMS (Ensemble Empirical Mode Decomposition in conjunction with the Block Least Mean Square algorithm) and DWT-NN (Discrete Wavelet Transform followed by Neural Network) methods in minimizing the artifacts from recorded ECG signals, and compares......Electrocardiogram (ECG) is a widely used noninvasive method to study the rhythmic activity of the heart and thereby to detect the abnormalities. However, these signals are often obscured by artifacts from various sources and minimization of these artifacts are of paramount important. This paper....... Results clearly show that both the methods works equally well when used on Type-I signals. However, on Type-II signals the DWTNN performed better. In the case of real ECG data, though both methods performed similar, the DWT-NN method was a slightly better in terms of minimizing the high frequency...

  13. Ventricular Repolarization Evaluation From Surface ECG for Identification of the Patients With Increased Myocardial Electrical Instability

    National Research Council Canada - National Science Library

    Lass, Jaanus

    2001-01-01

    In order to reveal the possible correlation between the level of myocardial electrical instability assessed at Holter monitoring and certain ECG parameters characterizing ventricular repolarization...

  14. Evaluation of a novel portable capacitive ECG system in the clinical practice for a fast and simple ECG assessment in patients presenting with chest pain: FIDET (Fast Infarction Diagnosis ECG Trial)

    OpenAIRE

    Rasenack, Eva C. L.; Oehler, Martin; Els?sser, Albrecht; Schilling, Meinhard; Maier, Lars S.

    2012-01-01

    Background Electrocardiogram (ECG) assessment plays a crucial role in patients presenting with chest pain and suspected acute coronary syndrome (ACS). In a pilot study, we previously evaluated a capacitive ECG system (cECG) as a novel ECG technique for a fast and simple ECG assessment in patients with ST-elevation myocardial infarction (STEMI). In a next step, the sensitivity and specificity of this novel ECG technique have to be assessed in patients with ACS. Hypothesis The Fast Infarction D...

  15. The Normal Electrocardiogram: Resting 12-Lead and Electrocardiogram Monitoring in the Hospital.

    Science.gov (United States)

    Harris, Patricia R E

    2016-09-01

    The electrocardiogram (ECG) is a well-established diagnostic tool extensively used in clinical settings. Knowledge of cardiac rhythm and mastery of cardiac waveform interpretation are fundamental for intensive care nurses. Recognition of the normal findings for the 12-lead ECG and understanding the significance of changes from baseline in continuous cardiac monitoring are essential steps toward ensuring safe patient care. This article highlights historical developments in electrocardiography, describes the normal resting 12-lead ECG, and discusses the need for continuous cardiac monitoring. In addition, future directions for the ECG are explored briefly. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Effects of Malaria on Blood Pressure, Heart Rate, Electrocardiogram ...

    African Journals Online (AJOL)

    The effect of malaria on blood pressure, heart rate, electrocardiogram and the cardiovascular responses to postural change were studied in malaria patients. Blood pressure was measured by the sphygmomanometric-auscultatory method. Standard ECG machine was used to record the electrocardiogram. Heart rate was ...

  17. [New knowledge of the modifiability of QRS amplitudes of the surface electrocardiogram of the transplanted human heart].

    Science.gov (United States)

    Kriehuber, E A

    1987-01-15

    Applying immunosuppressive therapy with Ciclosporin A, the myocardium shows only little or no oedema in the cardiac rejection process. Thus the usefulness of electrocardiographic diagnosis using QRS-amplitudes of the surface electrocardiogram (unipolar precordial chest leads) for the early recognition of the (acute) cardiac rejection process, is considerably limited if not questionable when compared with the pre-ciclosporin period (63 cases with heart transplants). In a heart-lung transplant for instance a massive accumulation of fluid in the lungs (erroneously) can influence the QRS-amplitudes. In addition, the cardiac rejection index (KRI) obtained by unipolar chest leads and other electrocardiographic alterations should be watched continuously. With a high degree of reliance, the intra-myocardial electrogram (IMEG) permits a better diagnosis of the acute cardiac rejection process. For the early clinical diagnosis the use of additional noninvasive methods of examinations is advisable.

  18. The asymptomatic teenager with an abnormal electrocardiogram.

    Science.gov (United States)

    Singh, Harinder R

    2014-02-01

    Use of medications for attention-deficit hyperkinetic disorder and preparticipation sports physical examination has led to an increase in number of electrocardiograms (ECG) performed during adolescence. Interpreting ECGs in children and young adults must take into account the evolutionary changes with age and the benign variants, which are usually not associated with heart disease. It is crucial for primary-care providers to recognize the changes on ECG associated with heart disease and risk of sudden death. In this article, the significance, sensitivity, specificity, and the diagnostic workup of these findings in the asymptomatic teenager are discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. [Analysis of pacemaker ECGs].

    Science.gov (United States)

    Israel, Carsten W; Ekosso-Ejangue, Lucy; Sheta, Mohamed-Karim

    2015-09-01

    The key to a successful analysis of a pacemaker electrocardiogram (ECG) is the application of the systematic approach used for any other ECG without a pacemaker: analysis of (1) basic rhythm and rate, (2) QRS axis, (3) PQ, QRS and QT intervals, (4) morphology of P waves, QRS, ST segments and T(U) waves and (5) the presence of arrhythmias. If only the most obvious abnormality of a pacemaker ECG is considered, wrong conclusions can easily be drawn. If a systematic approach is skipped it may be overlooked that e.g. atrial pacing is ineffective, the left ventricle is paced instead of the right ventricle, pacing competes with intrinsic conduction or that the atrioventricular (AV) conduction time is programmed too long. Apart from this analysis, a pacemaker ECG which is not clear should be checked for the presence of arrhythmias (e.g. atrial fibrillation, atrial flutter, junctional escape rhythm and endless loop tachycardia), pacemaker malfunction (e.g. atrial or ventricular undersensing or oversensing, atrial or ventricular loss of capture) and activity of specific pacing algorithms, such as automatic mode switching, rate adaptation, AV delay modifying algorithms, reaction to premature ventricular contractions (PVC), safety window pacing, hysteresis and noise mode. A systematic analysis of the pacemaker ECG almost always allows a probable diagnosis of arrhythmias and malfunctions to be made, which can be confirmed by pacemaker control and can often be corrected at the touch of the right button to the patient's benefit.

  20. The electrocardiogram in traumatic right atrial rupture

    NARCIS (Netherlands)

    van Veldhuisen, DJ; van den Berg, MP

    1999-01-01

    We:report the case of a previously healthy 20-year-old man who had a traumatic rupture of the right atrium. On admission an electrocardiogram (ECG) was recorded which is highly remarkable and, retrospectively, suggestive for the diagnosis. The patient died soon after the EGG, and the diagnosis was

  1. Characterization of post MI electrocardiogram using power ratio ...

    African Journals Online (AJOL)

    Myocardial infarction (MI) is the irreversible necrosis of heart muscles caused by prolonged ischemic condition. Subsequently the presence of damaged tissues in post-MI patients is expected to have an effect on their electrocardiogram (ECG). Hence, this paper proposes characterization of post-MI ECG from bipolar and ...

  2. Gender differences in the electrocardiogram screening of athletes

    NARCIS (Netherlands)

    Bessem, Bram; de Bruijn, Matthijs C.; Nieuwland, Wybe

    Objectives: Gender-related differences are frequently used in medicine. Electrocardiograms are also subject to such differences. This study evaluated gender differences in ECG parameters of young athletes, discussing the possible implications of these differences for ECG criteria used in the

  3. Electrocardiogram de-noising based on forward wavelet transform ...

    Indian Academy of Sciences (India)

    Abstract. In this paper, we propose a new technique of Electrocardiogram (ECG) signal de-noising based on thresholding of the coefficients obtained from the appli- cation of the Forward Wavelet Transform Translation Invariant (FWT_TI) to each. Bionic Wavelet coefficient. The De-noise De-noised ECG is obtained from the ...

  4. Advanced ECG in 2016: is there more than just a tracing?

    Science.gov (United States)

    Reichlin, Tobias; Abächerli, Roger; Twerenbold, Raphael; Kühne, Michael; Schaer, Beat; Müller, Christian; Sticherling, Christian; Osswald, Stefan

    2016-01-01

    The 12-lead electrocardiogram (ECG) is the most frequently used technology in clinical cardiology. It is critical for evidence-based management of patients with most cardiovascular conditions, including patients with acute myocardial infarction, suspected chronic cardiac ischaemia, cardiac arrhythmias, heart failure and implantable cardiac devices. In contrast to many other techniques in cardiology, the ECG is simple, small, mobile, universally available and cheap, and therefore particularly attractive. Standard ECG interpretation mainly relies on direct visual assessment. The progress in biomedical computing and signal processing, and the available computational power offer fascinating new options for ECG analysis relevant to all fields of cardiology. Several digital ECG markers and advanced ECG technologies have shown promise in preliminary studies. This article reviews promising novel surface ECG technologies in three different fields. (1) For the detection of myocardial ischaemia and infarction, QRS morphology feature analysis, the analysis of high frequency QRS components (HF-QRS) and methods using vectorcardiography as well as ECG imaging are discussed. (2) For the identification and management of patients with cardiac arrhythmias, methods of advanced P-wave analysis are discussed and the concept of ECG imaging for noninvasive localisation of cardiac arrhythmias is presented. (3) For risk stratification of sudden cardiac death and the selection of patients for medical device therapy, several novel markers including an automated QRS-score for scar quantification, the QRS-T angle or the T-wave peak-to-end-interval are discussed. Despite the existing preliminary data, none of the advanced ECG markers and technologies has yet accomplished the transition into clinical practice. Further refinement of these technologies and broader validation in large unselected patient cohorts are the critical next step needed to facilitate translation of advanced ECG technologies

  5. Diagnostic accuracy of pace spikes in the electrocardiogram to diagnose paced rhythm

    DEFF Research Database (Denmark)

    Andersson, Hedvig Bille; Hansen, Marco Bo; Thorsberger, Mads

    2015-01-01

    OBJECTIVE: To determine how often cardiac resynchronization therapy (CRT) pacing systems generate visible pace spikes in the electrocardiogram (ECG). METHODS: In 46 patients treated with CRT pacing systems, we recorded ECGs during intrinsic rhythm, atrial pacing and ventricular pacing. ECGs were...

  6. A Correction Formula for the ST Segment Measurements for the AC-coupled Electrocardiograms

    DEFF Research Database (Denmark)

    Schmid, Ramun; Isaksen, Jonas; Leber, Remo

    2017-01-01

    Goal: The ST segment of an electrocardiogram (ECG) is very important for the correct diagnosis of an acute myocardial infarction. Most clinical ECGs are recorded using an AC-coupled ECG amplifier. It is well known, that first-order high-pass filters used for the AC coupling can affect the ST...

  7. Teaching electrocardiogram basics using dance and movement.

    Science.gov (United States)

    Schultz, Karen K; Brackbill, Marcia L

    2009-07-10

    To implement and assess an innovative approach to teaching electrocardiogram (ECG) rhythms using dance and movement. Recognition of ECG rhythms was taught to a group of third-year pharmacy students using dance and movement via collaboration with a dance faculty member. A control group was taught using traditional pharmacy lecture and PowerPoint slides. A pretest and posttest were administered to both groups. There was a trend in test score improvement in the dance and movement group. After the sessions, a focus group was held to assess student perceptions using qualitative methods. Students thought the addition of dance helped them with speed of retention and recognition of ECG rhythms. Some students reported feeling out of their comfort zone. Interprofessional collaboration between pharmacy and dance faculty members resulted in an innovative teaching methodology for ECG rhythms that increased test scores.

  8. Improvement of electrocardiogram by empirical wavelet transform

    Science.gov (United States)

    Chanchang, Vikanda; Kumchaiseemak, Nakorn; Sutthiopad, Malee; Luengviriya, Chaiya

    2017-09-01

    Electrocardiogram (ECG) is a crucial tool in the detection of cardiac arrhythmia. It is also often used in a routine physical exam, especially, for elderly people. This graphical representation of electrical activity of heart is obtained by a measurement of voltage at the skin; therefore, the signal is always contaminated by noise from various sources. For a proper interpretation, the quality of the ECG should be improved by a noise reduction. In this article, we present a study of a noise filtration in the ECG by using an empirical wavelet transform (EWT). Unlike the traditional wavelet method, EWT is adaptive since the frequency spectrum of the ECG is taken into account in the construction of the wavelet basis. We show that the signal-to-noise ratio increases after the noise filtration for different noise artefacts.

  9. [The electrocardiogram in the paediatric age group].

    Science.gov (United States)

    Sanches, M; Coelho, A; Oliveira, E; Lopes, A

    2014-09-01

    A properly interpreted electrocardiogram (ECG) provides important information and is an inexpensive and easy test to perform. It continues to be the method of choice for the diagnosis of arrhythmias. Although the principles of cardiac electrophysiology are the same, there are anatomical and physiological age-dependent changes which produce specific alterations in the paediatric ECG, and which may be misinterpreted as pathological. The intention of this article is to address in a systematic way the most relevant aspects of the paediatric ECG, to propose a possible reading scheme of the ECG and to review the electrocardiograph tracings most frequently found in the paediatric age group. Copyright © 2013 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.

  10. Preoperative study of the surface ECG for the prognosis of atrial fibrillation maze surgery outcome at discharge

    International Nuclear Information System (INIS)

    Hernández, Antonio; Rieta, José Joaquín; Alcaraz, Raúl; Hornero, Fernando

    2014-01-01

    The Cox-maze surgery is an effective procedure for terminating atrial fibrillation (AF) in patients requiring open-heart surgery associated with another heart disease. After the intervention, regardless of the patient's rhythm, all are treated with oral anticoagulants and antiarrhythmic drugs prior to discharge. Furthermore, patients maintaining AF before discharge could also be treated with electrical cardioversion (ECV). In view of this, a preoperative prognosis of the patient's rhythm at discharge would be helpful for optimizing drug therapy planning as well as for advancing ECV therapy. This work analyzes 30 preoperative electrocardiograms (ECGs) from patients suffering from AF in order to predict the Cox-maze surgery outcome at discharge. Two different characteristics of the AF pattern have been studied. On the one hand, the atrial activity (AA) organization, which provides information about the number of propagating wavelets in the atria, was investigated. AA organization has been successfully used in previous studies related to spontaneous reversion of paroxysmal AF and to the outcome of ECV. To assess organization, the dominant atrial frequency (DAF) and sample entropy (SampEn) have been computed. On the other hand, the second characteristic studied was the fibrillatory wave (f-wave) amplitude, which has been demonstrated to be a valuable indicator of the Cox-maze surgery outcome in previous studies. Moreover, this parameter has been obtained through a new methodology, based on computing the f-wave average power (fWP). Finally, all the computed indices were combined in a decision tree in order to improve prediction capability. Results for the DAF yielded a sensitivity (Se), a specificity (Sp) and an accuracy (Acc) of 61.54%, 82.35% and 73.33%, respectively. For SampEn the values were 69.23%, 76.00% and 73.33%, respectively, and for fWP they were 92.31%, 82.35% and 86.67%, respectively. Finally, the decision tree combining the three parameters

  11. Individual identification via electrocardiogram analysis.

    Science.gov (United States)

    Fratini, Antonio; Sansone, Mario; Bifulco, Paolo; Cesarelli, Mario

    2015-08-14

    During last decade the use of ECG recordings in biometric recognition studies has increased. ECG characteristics made it suitable for subject identification: it is unique, present in all living individuals, and hard to forge. However, in spite of the great number of approaches found in literature, no agreement exists on the most appropriate methodology. This study aimed at providing a survey of the techniques used so far in ECG-based human identification. Specifically, a pattern recognition perspective is here proposed providing a unifying framework to appreciate previous studies and, hopefully, guide future research. We searched for papers on the subject from the earliest available date using relevant electronic databases (Medline, IEEEXplore, Scopus, and Web of Knowledge). The following terms were used in different combinations: electrocardiogram, ECG, human identification, biometric, authentication and individual variability. The electronic sources were last searched on 1st March 2015. In our selection we included published research on peer-reviewed journals, books chapters and conferences proceedings. The search was performed for English language documents. 100 pertinent papers were found. Number of subjects involved in the journal studies ranges from 10 to 502, age from 16 to 86, male and female subjects are generally present. Number of analysed leads varies as well as the recording conditions. Identification performance differs widely as well as verification rate. Many studies refer to publicly available databases (Physionet ECG databases repository) while others rely on proprietary recordings making difficult them to compare. As a measure of overall accuracy we computed a weighted average of the identification rate and equal error rate in authentication scenarios. Identification rate resulted equal to 94.95 % while the equal error rate equal to 0.92 %. Biometric recognition is a mature field of research. Nevertheless, the use of physiological signals

  12. Extraction of fetal ECG signal by an improved method using extended Kalman smoother framework from single channel abdominal ECG signal.

    Science.gov (United States)

    Panigrahy, D; Sahu, P K

    2017-03-01

    This paper proposes a five-stage based methodology to extract the fetal electrocardiogram (FECG) from the single channel abdominal ECG using differential evolution (DE) algorithm, extended Kalman smoother (EKS) and adaptive neuro fuzzy inference system (ANFIS) framework. The heart rate of the fetus can easily be detected after estimation of the fetal ECG signal. The abdominal ECG signal contains fetal ECG signal, maternal ECG component, and noise. To estimate the fetal ECG signal from the abdominal ECG signal, removal of the noise and the maternal ECG component presented in it is necessary. The pre-processing stage is used to remove the noise from the abdominal ECG signal. The EKS framework is used to estimate the maternal ECG signal from the abdominal ECG signal. The optimized parameters of the maternal ECG components are required to develop the state and measurement equation of the EKS framework. These optimized maternal ECG parameters are selected by the differential evolution algorithm. The relationship between the maternal ECG signal and the available maternal ECG component in the abdominal ECG signal is nonlinear. To estimate the actual maternal ECG component present in the abdominal ECG signal and also to recognize this nonlinear relationship the ANFIS is used. Inputs to the ANFIS framework are the output of EKS and the pre-processed abdominal ECG signal. The fetal ECG signal is computed by subtracting the output of ANFIS from the pre-processed abdominal ECG signal. Non-invasive fetal ECG database and set A of 2013 physionet/computing in cardiology challenge database (PCDB) are used for validation of the proposed methodology. The proposed methodology shows a sensitivity of 94.21%, accuracy of 90.66%, and positive predictive value of 96.05% from the non-invasive fetal ECG database. The proposed methodology also shows a sensitivity of 91.47%, accuracy of 84.89%, and positive predictive value of 92.18% from the set A of PCDB.

  13. Pharmacokinetics of intravenously and orally administered sotalol hydrochloride in horses and effects on surface electrocardiogram and left ventricular systolic function.

    Science.gov (United States)

    Broux, B; De Clercq, D; Decloedt, A; De Baere, S; Devreese, M; Van Der Vekens, N; Ven, S; Croubels, S; van Loon, G

    2016-02-01

    Arrhythmias are common in horses. Some, such as frequent atrial or ventricular premature beats, may require long-term anti-arrhythmic therapy. In humans and small animals, sotalol hydrochloride (STL) is often used for chronic oral anti-arrhythmic therapy. STL prolongs repolarization and the effective refractory period in all cardiac tissues. No information on STL pharmacokinetics or pharmacodynamics in horses is available and the aim of this study was to evaluate the pharmacokinetics of intravenously (IV) and orally (PO) administered STL and the effects on surface electrocardiogram and left ventricular systolic function. Six healthy horses were given 1 mg STL/kg bodyweight either IV or PO. Blood samples to determine plasma STL concentrations were taken before and at several time points after STL administration. Electrocardiography and echocardiography were performed at different time points before and after IV STL administration. Mean peak plasma concentrations after IV and PO administration of STL were 1624 ng/mL and 317 ng/mL, respectively. The oral bioavailability was intermediate (48%) with maximal absorption after 0.94 h, a moderate distribution and a mean elimination half-life of 15.24 h. After IV administration, there was a significant increase in QT interval, but no significant changes in other electrocardiographic and echocardiographic parameters. Transient transpiration was observed after IV administration, but no adverse effects were noted after a single oral dose of 1 mg/kg STL in any of the horses. It was concluded that STL has an intermediate oral bioavailability in the horse and might be useful in the treatment of equine arrhythmias. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Applicability of initial optimal maternal and fetal electrocardiogram combination vectors to subsequent recordings

    Science.gov (United States)

    Yan, Hua-Wen; Huang, Xiao-Lin; Zhao, Ying; Si, Jun-Feng; Liu, Tie-Bing; Liu, Hong-Xing

    2014-11-01

    A series of experiments are conducted to confirm whether the vectors calculated for an early section of a continuous non-invasive fetal electrocardiogram (fECG) recording can be directly applied to subsequent sections in order to reduce the computation required for real-time monitoring. Our results suggest that it is generally feasible to apply the initial optimal maternal and fetal ECG combination vectors to extract the fECG and maternal ECG in subsequent recorded sections.

  15. Competency in ECG Interpretation Among Medical Students

    Science.gov (United States)

    Kopeć, Grzegorz; Magoń, Wojciech; Hołda, Mateusz; Podolec, Piotr

    2015-01-01

    Background Electrocardiogram (ECG) is commonly used in diagnosis of heart diseases, including many life-threatening disorders. We aimed to assess skills in ECG interpretation among Polish medical students and to analyze the determinants of these skills. Material/Methods Undergraduates from all Polish medical schools were asked to complete a web-based survey containing 18 ECG strips. Questions concerned primary ECG parameters (rate, rhythm, and axis), emergencies, and common ECG abnormalities. Analysis was restricted to students in their clinical years (4th–6th), and students in their preclinical years (1st–3rd) were used as controls. Results We enrolled 536 medical students (females: n=299; 55.8%), aged 19 to 31 (23±1.6) years from all Polish medical schools. Most (72%) were in their clinical years. The overall rate of good response was better in students in years 4th–5th than those in years 1st–3rd (66% vs. 56%; pCompetency in ECG interpretation was higher in students who reported ECG self-learning (69% vs. 62%; pstudents who attended or did not attend regular ECG classes (66% vs. 66%; p=0.99). On multivariable analysis (pyears (OR: 2.45 [1.35–4.46] and self-learning (OR: 2.44 [1.46–4.08]) determined competency in ECG interpretation. Conclusions Polish medical students in their clinical years have a good level of competency in interpreting the primary ECG parameters, but their ability to recognize ECG signs of emergencies and common heart abnormalities is low. ECG interpretation skills are determined by self-education but not by attendance at regular ECG classes. Our results indicate qualitative and quantitative deficiencies in teaching ECG interpretation at medical schools. PMID:26541993

  16. Hypoglycemia-associated electroencephalogram and electrocardiogram changes appear simultaneously

    DEFF Research Database (Denmark)

    Larsen, Anine Poulsen; Højlund, Kurt; Poulsen, Mikael Kjær

    2013-01-01

    Tight glycemic control in type 1 diabetes mellitus (T1DM) may be accomplished only if severe hypoglycemia can be prevented. Biosensor alarms based on the body's reactions to hypoglycemia have been suggested. In the present study, we analyzed three lead electrocardiogram (ECG) and single-channel e......Tight glycemic control in type 1 diabetes mellitus (T1DM) may be accomplished only if severe hypoglycemia can be prevented. Biosensor alarms based on the body's reactions to hypoglycemia have been suggested. In the present study, we analyzed three lead electrocardiogram (ECG) and single...

  17. Systematic analysis of ECG predictors of sinus rhythm maintenance after electrical cardioversion for persistent atrial fibrillation.

    Science.gov (United States)

    Lankveld, Theo; de Vos, Cees B; Limantoro, Ione; Zeemering, Stef; Dudink, Elton; Crijns, Harry J; Schotten, Ulrich

    2016-05-01

    Electrical cardioversion (ECV) is one of the rhythm control strategies in patients with persistent atrial fibrillation (AF). Unfortunately, recurrences of AF are common after ECV, which significantly limits the practical benefit of this treatment in patients with AF. The objectives of this study were to identify noninvasive complexity or frequency parameters obtained from the surface electrocardiogram (ECG) to predict sinus rhythm (SR) maintenance after ECV and to compare these ECG parameters with clinical predictors. We studied a wide variety of ECG-derived time- and frequency-domain AF complexity parameters in a prospective cohort of 502 patients with persistent AF referred for ECV. During 1-year follow-up, 161 patients (32%) maintained SR. The best clinical predictor of SR maintenance was antiarrhythmic drug (AAD) treatment. A model including clinical parameters predicted SR maintenance with a mean cross-validated area under the receiver operating characteristic curve (AUC) of 0.62 ± 0.05. The best single ECG parameter was the dominant frequency (DF) on lead V6. Combining several ECG parameters predicted SR maintenance with a mean AUC of 0.64 ± 0.06. Combining clinical and ECG parameters improved prediction to a mean AUC of 0.67 ± 0.05. Although the DF was affected by AAD treatment, excluding patients taking AADs did not significantly lower the predictive performance captured by the ECG. ECG-derived parameters predict SR maintenance during 1-year follow-up after ECV at least as good as known clinical predictors of rhythm outcome. The DF proved to be the most powerful ECG-derived predictor. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  18. Accurate Interpretation of the 12-Lead ECG Electrode Placement: A Systematic Review

    Science.gov (United States)

    Khunti, Kirti

    2014-01-01

    Background: Coronary heart disease (CHD) patients require monitoring through ECGs; the 12-lead electrocardiogram (ECG) is considered to be the non-invasive gold standard. Examples of incorrect treatment because of inaccurate or poor ECG monitoring techniques have been reported in the literature. The findings that only 50% of nurses and less than…

  19. ECG Identification System Using Neural Network with Global and Local Features

    Science.gov (United States)

    Tseng, Kuo-Kun; Lee, Dachao; Chen, Charles

    2016-01-01

    This paper proposes a human identification system via extracted electrocardiogram (ECG) signals. Two hierarchical classification structures based on global shape feature and local statistical feature is used to extract ECG signals. Global shape feature represents the outline information of ECG signals and local statistical feature extracts the…

  20. Computational techniques for ECG analysis and interpretation in light of their contribution to medical advances.

    Science.gov (United States)

    Lyon, Aurore; Mincholé, Ana; Martínez, Juan Pablo; Laguna, Pablo; Rodriguez, Blanca

    2018-01-01

    Widely developed for clinical screening, electrocardiogram (ECG) recordings capture the cardiac electrical activity from the body surface. ECG analysis can therefore be a crucial first step to help diagnose, understand and predict cardiovascular disorders responsible for 30% of deaths worldwide. Computational techniques, and more specifically machine learning techniques and computational modelling are powerful tools for classification, clustering and simulation, and they have recently been applied to address the analysis of medical data, especially ECG data. This review describes the computational methods in use for ECG analysis, with a focus on machine learning and 3D computer simulations, as well as their accuracy, clinical implications and contributions to medical advances. The first section focuses on heartbeat classification and the techniques developed to extract and classify abnormal from regular beats. The second section focuses on patient diagnosis from whole recordings, applied to different diseases. The third section presents real-time diagnosis and applications to wearable devices. The fourth section highlights the recent field of personalized ECG computer simulations and their interpretation. Finally, the discussion section outlines the challenges of ECG analysis and provides a critical assessment of the methods presented. The computational methods reported in this review are a strong asset for medical discoveries and their translation to the clinical world may lead to promising advances. © 2018 The Author(s).

  1. Performance evaluation of carbon black based electrodes for underwater ECG monitoring.

    Science.gov (United States)

    Reyes, Bersain A; Posada-Quintero, Hugo F; Bales, Justin R; Chon, Ki H

    2014-01-01

    Underwater electrocardiogram (ECG) monitoring currently uses Ag/AgCl electrodes and requires sealing of the electrodes to avoid water intrusion, but this procedure is time consuming and often results in severe irritations or even tearing of the skin. To alleviate these problems, our research team developed hydrophobic electrodes comprised of a mixture of carbon black powder (CB) and polydimethylsiloxane (PDMS) that provide all morphological waveforms without distortion of an ECG signal for dry and water-immersed conditions. Performance comparison of CB/PDMS electrodes to adhesive Ag/AgCl hydrogel electrodes was carried out in three different scenarios which included recordings from a dry surface, water immersion, and post-water immersion conditions. CB/PDMS electrodes were able to acquire ECG signals highly correlated with those from adhesive Ag/AgCl electrodes during all conditions. Statistical reduction in ECG amplitude (pelectrodes when compared to Ag/AgCl electrodes sealed with their waterproof adhesive tape. Besides this reduction readability of the recordings was not obscured and all morphological waveforms of the ECG signal were discernible. The advantages of our CB/PDMS electrodes are that they are reusable, can be fabricated economically, and most importantly, high-fidelity underwater ECG signals can be acquired without relying on the heavy use of waterproof sealing.

  2. A Real-Time Intrauterine Catheter Technique for Fetal Electrocardiogram Monitoring

    National Research Council Canada - National Science Library

    Horner, S

    2001-01-01

    ..., two sensors that include the invasive scalp electrode and intrauterine pressure catheter are used clink ally, Signal processing is required to obtain a FECG via the IC, Usually the maternal electrocardiogram (ECG...

  3. Design of portable electrocardiogram device using DSO138

    Science.gov (United States)

    Abuzairi, Tomy; Matondang, Josef Stevanus; Purnamaningsih, Retno Wigajatri; Basari, Ratnasari, Anita

    2018-02-01

    Cardiovascular disease has been one of the leading causes of sudden cardiac deaths in many countries, covering Indonesia. Electrocardiogram (ECG) is a medical test to detect cardiac abnormalities by measuring the electrical activity generated by the heart, as the heart contracts. By using ECG, we can observe anomaly at the time of heart abnormalities. In this paper, design of portable ECG device is presented. The portable ECG device was designed to easily use in the village clinic or houses, due to the small size device and other benefits. The device was designed by using four units: (1) ECG electrode; (2) ECG analog front-end; (3) DSO138; and (4) battery. To create a simple electrode system in the portable ECG, 1-lead ECG with two electrodes were applied. The analog front-end circuitry consists of three integrated circuits, an instrumentation amplifier AD820AN, a low noise operational amplifier OPA134, and a low offset operational amplifier TL082. Digital ECG data were transformed to graphical data on DSO138. The results show that the portable ECG is successfully read the signal from 1-lead ECG system.

  4. Assessment of the electrocardiogram in dogs with visceral leishmaniasis

    OpenAIRE

    Sousa, Marlos G.; Carareto, Roberta; Silva, Jeanna G.; Oliveira, Juliana

    2013-01-01

    As myocarditis and arrhythmias have been shown to occur in both human beings and dogs with leishmaniasis, electrocardiograms of 105 dogs serologically positive for this disease were assessed for rhythm disturbances and changes in ECG waves. A few expressive alterations were seen, including sinus arrest, right bundle branch block, and atrial premature beats in 14.3%, 4.8%, and 4.8% of the studied subjects, respectively. Also, the analysis of ECG waves showed changes suggestive of left atrium a...

  5. Improving electrocardiogram interpretation skills for medical students

    Directory of Open Access Journals (Sweden)

    Patel K

    2017-01-01

    Full Text Available Kunj Patel,1 Omar El Tokhy,1 Shlok Patel,2 Hanna Maroof31Department of Investigative Medicine, Faculty of Medicine, Imperial College London, 2Department of Medical Research, Faculty of Medicine, Barts and The London School of Medicine and Dentistry, 3GKT School of Medical Education, Faculty of Life Sciences and Medicine, King’s College of London, London, UKWe read with great interest the article by Zeng at al1 who propose a new electrocardiogram (ECG teaching method called the “graphics-sequence memory method”. An ECG is one of the most important diagnostic tests and is currently used as a gold standard for the diagnosis of a number of cardiac diseases. We appreciate that it can be a challenging concept to teach, often bringing frustration to the educators trained in ECG interpretation. Zeng et al1 highlight a deficiency in learning through the traditional Chinese disease-based teaching method, resulting in a relative inability to interpret ECGs where the diagnosis is not quite so straightforward. Accumulation of evidence2 has suggested that a significant proportion of undergraduate medical students do not feel competent in their interpretation of an ECG. Therefore, the authors are right to suggest a novel approach with the dual benefit of aiding teaching and improving learning and confidence when interpreting an ECG.View original paper by Zeng and colleagues.

  6. Is 10-second electrocardiogram recording enough for accurately estimating heart rate in atrial fibrillation.

    Science.gov (United States)

    Shuai, Wei; Wang, Xi-Xing; Hong, Kui; Peng, Qiang; Li, Ju-Xiang; Li, Ping; Chen, Jing; Cheng, Xiao-Shu; Su, Hai

    2016-07-15

    At present, the estimation of rest heart rate (HR) in atrial fibrillation (AF) is obtained by apical auscultation for 1min or on the surface electrocardiogram (ECG) by multiplying the number of RR intervals on the 10second recording by six. But the reasonability of 10second ECG recording is controversial. ECG was continuously recorded at rest for 60s to calculate the real rest HR (HR60s). Meanwhile, the first 10s and 30s ECG recordings were used for calculating HR10s (sixfold) and HR30s (twofold). The differences of HR10s or HR30s with the HR60s were compared. The patients were divided into three sub-groups on the HR60s 100bpm. No significant difference among the mean HR10s, HR30s and HR60s was found. A positive correlation existed between HR10s and HR60s or HR30s and HR60s. Bland-Altman plot showed that the 95% reference limits were high as -11.0 to 16.0bpm for HR10s, but for HR30s these values were only -4.5 to 5.2bpm. Among the three subgroups with HR60s 100bpm, the 95% reference limits with HR60s were -8.9 to 10.6, -10.5 to 14.0 and -11.3 to 21.7bpm for HR10s, but these values were -3.9 to 4.3, -4.1 to 4.6 and -5.3 to 6.7bpm for HR30s. As 10s ECG recording could not provide clinically accepted estimation HR, ECG should be recorded at least for 30s in the patients with AF. It is better to record ECG for 60s when the HR is rapid. Copyright © 2016. Published by Elsevier Ireland Ltd.

  7. Electrocardiogram artifact caused by rigors mimicking narrow complex tachycardia: a case report.

    Science.gov (United States)

    Matthias, Anne Thushara; Indrakumar, Jegarajah

    2014-02-04

    The electrocardiogram (ECG) is useful in the diagnosis of cardiac and non-cardiac conditions. Rigors due to shivering can cause electrocardiogram artifacts mimicking various cardiac rhythm abnormalities. We describe an 80-year-old Sri Lankan man with an abnormal electrocardiogram mimicking narrow complex tachycardia during the immediate post-operative period. Electrocardiogram changes caused by muscle tremor during rigors could mimic a narrow complex tachycardia. Identification of muscle tremor as a cause of electrocardiogram artifact can avoid unnecessary pharmacological and non-pharmacological intervention to prevent arrhythmias.

  8. 77 FR 6127 - Submission of Extended Digital Electrocardiogram Waveform Data; Notice of Public Meeting

    Science.gov (United States)

    2012-02-07

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2012-N-0084] Submission of Extended Digital Electrocardiogram Waveform Data; Notice of Public Meeting AGENCY: Food and... electrocardiogram (ECG) data gathered to assess a drug's adverse effects on heart function should be submitted for...

  9. Electrocardiogram Signal and Linear Time-Frequency Transforms

    Science.gov (United States)

    Krishna, B. T.

    2014-12-01

    The diagnostic analysis of non-stationary multi component signals such as electrocardiogram (ECG) involves the use of time-frequency transforms. So, the application of time-frequency transforms to an ECG signal is an important problem of research. In this paper, initially, linear transforms like short time Fourier transform, continuous wavelet transforms, s-transform etc. are revisited. Then the application of these transforms to normal and abnormal ECG signals is illustrated. It has been observed that s-transform provides better time and frequency resolution compared to other linear transforms. The fractional Fourier transform provides rotation to the spectrogram representation.

  10. Hypoglycemia-associated electroencephalogram and electrocardiogram changes appear simultaneously

    DEFF Research Database (Denmark)

    Larsen, Anine Poulsen; Højlund, Kurt; Poulsen, Mikael Kjær

    2013-01-01

    Tight glycemic control in type 1 diabetes mellitus (T1DM) may be accomplished only if severe hypoglycemia can be prevented. Biosensor alarms based on the body's reactions to hypoglycemia have been suggested. In the present study, we analyzed three lead electrocardiogram (ECG) and single-channel e...

  11. Evaluation of Routine Preoperative Electrocardiogram-A Lagos ...

    African Journals Online (AJOL)

    Introduction: Patients who are 40yrs and above are required to have routine preoperative electrocardiogram (ECG) prior to major elective surgery in our practice. This is aimed at detecting cardiac abnormalities that may contribute to peri- and post-operative morbidity and mortality. There is paucity of literature on this subject ...

  12. An Analysis Of QRS Interval Of The Electrocardiogram In ...

    African Journals Online (AJOL)

    Objectives: This cross-sectional study of the 12-lead electrocardiogram (ECG) was undertaken to establish the normal QRS interval of the adult Nigerian from Jos; to find significant correlation coefficients for QRS interval and the various anthropometric measurements and also to establish prediction equations for the QRS ...

  13. Cost-effectiveness of cardiotocography plus ST analysis of the fetal electrocardiogram compared with cardiotocography only

    NARCIS (Netherlands)

    Vijgen, Sylvia M. C.; Westerhuis, Michelle E. M. H.; Opmeer, Brent C.; Visser, Gerard H. A.; Moons, Karl G. M.; Porath, Martina M.; Oei, Guid S.; van Geijn, Herman P.; Bolte, Antoinette C.; Willekes, Christine; Nijhuis, Jan G.; van Beek, Erik; Graziosi, Giuseppe C. M.; Schuitemaker, Nico W. E.; van Lith, Jan M. M.; van den Akker, Eline S. A.; Drogtrop, Addy P.; van Dessel, Hendrikus J. H. M.; Rijnders, Robbert J. P.; Oosterbaan, Herman P.; Mol, Ben Willem J.; Kwee, Anneke

    2011-01-01

    To assess the cost-effectiveness of addition of ST analysis of the fetal electrocardiogram (ECG; STAN) to cardiotocography (CTG) for fetal surveillance during labor compared with CTG only. Cost-effectiveness analysis based on a randomized clinical trial on ST analysis of the fetal ECG. Obstetric

  14. Respiratory Information Extraction from Electrocardiogram Signals

    KAUST Repository

    Amin, Gamal El Din Fathy

    2010-12-01

    The Electrocardiogram (ECG) is a tool measuring the electrical activity of the heart, and it is extensively used for diagnosis and monitoring of heart diseases. The ECG signal reflects not only the heart activity but also many other physiological processes. The respiratory activity is a prominent process that affects the ECG signal due to the close proximity of the heart and the lungs. In this thesis, several methods for the extraction of respiratory process information from the ECG signal are presented. These methods allow an estimation of the lung volume and the lung pressure from the ECG signal. The potential benefit of this is to eliminate the corresponding sensors used to measure the respiration activity. A reduction of the number of sensors connected to patients will increase patients’ comfort and reduce the costs associated with healthcare. As a further result, the efficiency of diagnosing respirational disorders will increase since the respiration activity can be monitored with a common, widely available method. The developed methods can also improve the detection of respirational disorders that occur while patients are sleeping. Such disorders are commonly diagnosed in sleeping laboratories where the patients are connected to a number of different sensors. Any reduction of these sensors will result in a more natural sleeping environment for the patients and hence a higher sensitivity of the diagnosis.

  15. Sinabro: A Smartphone-Integrated Opportunistic Electrocardiogram Monitoring System

    Directory of Open Access Journals (Sweden)

    Sungjun Kwon

    2016-03-01

    Full Text Available In our preliminary study, we proposed a smartphone-integrated, unobtrusive electrocardiogram (ECG monitoring system, Sinabro, which monitors a user’s ECG opportunistically during daily smartphone use without explicit user intervention. The proposed system also monitors ECG-derived features, such as heart rate (HR and heart rate variability (HRV, to support the pervasive healthcare apps for smartphones based on the user’s high-level contexts, such as stress and affective state levels. In this study, we have extended the Sinabro system by: (1 upgrading the sensor device; (2 improving the feature extraction process; and (3 evaluating extensions of the system. We evaluated these extensions with a good set of algorithm parameters that were suggested based on empirical analyses. The results showed that the system could capture ECG reliably and extract highly accurate ECG-derived features with a reasonable rate of data drop during the user’s daily smartphone use.

  16. Using the 12-Lead Electrocardiogram in the Care of Athletic Patients.

    Science.gov (United States)

    Yeo, Tee Joo; Sharma, Sanjay

    2016-11-01

    This article summarizes the role of the 12-lead electrocardiogram (ECG) for the clinical care of athletes, with particular reference to the influence of age, gender, ethnicity, and type of sport on the appearance of the ECG, and its role in differentiating physiologic exercise-related changes from pathologic conditions implicated in sudden cardiac death (SCD). The article also explores the potential role of the ECG in detecting athletes at risk of SCD. In addition, the article reviews the evolution of ECG interpretation criteria and emphasizes the limitations of the ECG as well as the potential for future research. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Quality assessment of digital annotated ECG data from clinical trials by the FDA ECG Warehouse.

    Science.gov (United States)

    Sarapa, Nenad

    2007-09-01

    The FDA mandates that digital electrocardiograms (ECGs) from 'thorough' QTc trials be submitted into the ECG Warehouse in Health Level 7 extended markup language format with annotated onset and offset points of waveforms. The FDA did not disclose the exact Warehouse metrics and minimal acceptable quality standards. The author describes the Warehouse scoring algorithms and metrics used by FDA, points out ways to improve FDA review and suggests Warehouse benefits for pharmaceutical sponsors. The Warehouse ranks individual ECGs according to their score for each quality metric and produces histogram distributions with Warehouse-specific thresholds that identify ECGs of questionable quality. Automatic Warehouse algorithms assess the quality of QT annotation and duration of manual QT measurement by the central ECG laboratory.

  18. The design of heart sounds and electrocardiogram monitor system based Atmega 128L

    Science.gov (United States)

    Cao, Miao; An, Zhiyong; Zhang, Ying

    2006-11-01

    This paper introduces a realtime system which can acquire,process,store and display heart sounds and electrocardiogram(ECG) of the human body at the same time.It is composed of superior microprocessor--Atmega128L,large capacity Flash and the new type LCD.All hardwares adopt low power design and surface mounting package. The specialities of the system are low power, compact, and high intelligence. In consideration of transplant and solidity of the system, at the same time, it ensures that some complicated arithmetic can be realized.The system software applies mold construction and programs in C language. A model for automatic arithmetic is established for the feature extraction of ECG, realtime cardiotach ambulatory analysis is realized. The system is capable of recording ECG and heart sounds information in succession for 48 hours and it stores the no compression data synchronously. More than ten types of familiar heart diseases can be diagnosed in time by it automatically. The testing data achieved from this system is dependable, the diagnosing result is accurate and the waveform is no distortion. It solved a problem within the same kind of products effectively, that is, the dynamic ECG and heart sounds signal are acquired separately. The system do not affect the daily living and working of human being when it is used, so it is suited for clinical and family monitoring.

  19. Surface electrocardiogram detects signs of right ventricular pressure overload among acute-decompensated heart failure with preserved ejection fraction patients.

    Science.gov (United States)

    Martínez Santos, Paula; Vilacosta, Isidre; Batlle López, Elena; Sánchez Sauce, Beatriz; España Barrio, Elena; Jiménez Valtierra, Julia; de la Rosa Riestra, Adriana; Campuzano Ruiz, Raquel

    2016-01-01

    Pulmonary hypertension (PH) is a common finding among patients with heart failure and preserved ejection fraction (HFpEF) and contributes to develop right ventricular systolic dysfunction (RVSD). We evaluated the diagnostic accuracy of Flowers and Horan electrocardiographic criteria to detect significant right ventricular pressure overload. 123 patients were prospectively included. We used the Flowers and Horan (FH) ECG criteria to define RV enlargement (score >10). Echocardiographic measurements were performed blinded to the electrocardiographic results. Severe PH was found in 51.5%. Seventeen patients (16.5%) had a FH score >10 points. This was associated to RVSD (RR 2.66; 1.51-4.67 CI 95%, p=0.002), with 90.5% specificity and 34.4% sensitivity and to severe PH (RR 1.70; 1.16-2.50 CI 95%, p=0.028) with 91.9% specificity and 27.5% sensitivity. The ECG is a useful tool to classify HFpEF patients with echocardiographic signs of right ventricular pressure overload, in the absence of RBBB. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Wearable Textile Electrodes for ECG Measurement

    Directory of Open Access Journals (Sweden)

    Lukas Vojtech

    2013-01-01

    Full Text Available The electrocardiogram (ECG is one of the most important parameters for monitoring of the physiological state of a person. Currently available systems for ECG monitoring are both stationary and wearable, but the comfort of the monitored person is not at a satisfactory level because these systems are not part of standard clothing. This article is therefore devoted to the development and measurement of wearable textile electrodes for ECG measurement device with high comfort for the user. The electrode material is made of electrically conductive textile. This creates a textile composite that guarantees high comfort for the user while ensuring good quality of ECG measurements. The composite is implemented by a carrier (a T-shirt with flame retardant and sensing electrodes embroidered with yarn based on a mixture of polyester coated with silver nanoparticles and cotton. The electrodes not only provide great comfort but are also antibacterial and antiallergic due to silver nanoparticles.

  1. Exploring the Relationship Between Eye Movements and Electrocardiogram Interpretation Accuracy

    Science.gov (United States)

    Davies, Alan; Brown, Gavin; Vigo, Markel; Harper, Simon; Horseman, Laura; Splendiani, Bruno; Hill, Elspeth; Jay, Caroline

    2016-12-01

    Interpretation of electrocardiograms (ECGs) is a complex task involving visual inspection. This paper aims to improve understanding of how practitioners perceive ECGs, and determine whether visual behaviour can indicate differences in interpretation accuracy. A group of healthcare practitioners (n = 31) who interpret ECGs as part of their clinical role were shown 11 commonly encountered ECGs on a computer screen. The participants’ eye movement data were recorded as they viewed the ECGs and attempted interpretation. The Jensen-Shannon distance was computed for the distance between two Markov chains, constructed from the transition matrices (visual shifts from and to ECG leads) of the correct and incorrect interpretation groups for each ECG. A permutation test was then used to compare this distance against 10,000 randomly shuffled groups made up of the same participants. The results demonstrated a statistically significant (α  0.05) result in 5 of the 11 stimuli demonstrating that the gaze shift between the ECG leads is different between the groups making correct and incorrect interpretations and therefore a factor in interpretation accuracy. The results shed further light on the relationship between visual behaviour and ECG interpretation accuracy, providing information that can be used to improve both human and automated interpretation approaches.

  2. Making sense of the ECG: cases for self-assessment Making Sense of the ECG: Cases for Self-Assessment Houghton Andrew and Gray David Hodder Education £18.99 290pp 9780340946893 034094689X [Formula: see text].

    Science.gov (United States)

    2011-02-10

    This practical pocket-book approach to electrocardiogram (ECG) interpretation accompanies Making sense of the eCg by the same authors. it is also designed to be used alone to test knowledge of ECG interpretation and to make clinical decisions based on presented scenarios.

  3. Dynamic Changes in High-Sensitivity Cardiac Troponin I Are Associated with Dynamic Changes in Sum Absolute QRST Integral on Surface Electrocardiogram in Acute Decompensated Heart Failure.

    Science.gov (United States)

    Tereshchenko, Larisa G; Feeny, Albert; Shelton, Erica; Metkus, Thomas; Stolbach, Andrew; Mavunga, Ernest; Putman, Shannon; Korley, Frederick K

    2017-01-01

    A three-dimensional electrocardiographic (ECG) metric, the sum absolute QRST integral (SAI QRST), predicts ventricular arrhythmias in heart failure (HF) patients with implantable cardioverter defibrillator and mechanical response to cardiac resynchronization therapy. We hypothesized that there is an association between patient-specific changes in SAI QRST and myocardial injury as measured by high-sensitivity troponin I (hsTnI). Sum absolute integral QRST on resting 12-lead ECG and hsTnI were measured simultaneously, every 3 hours, and during 12-hour observation period in a prospective cohort of emergency department patients (n = 398; mean age 57.8 ± 13.2 years; 54% female, 64% black), diagnosed with acute coronary syndrome (ACS, n = 28), acutely decompensated HF (acute decompensated heart failure, n = 35), cardiac non-ACS (n = 19), or noncardiac condition (n = 316). Random-effects linear regression analysis assessed the association of SAI QRST and myocardial injury, with adjustment for demographics (age, sex, race), prevalent cardiovascular disease (myocardial infarction, history of revascularization, stroke, and HF), risk factors (diabetes, smoking, hypercholesterolemia, hypertension, and cocaine use), and left bundle branch block. Within the entire cohort, SAI QRST decreased by 3 (95%CI -5 to -1) mV*ms every 3 hours. A 10-fold increase in hsTnI was associated with a 7.7 (0.6-14.9) mV*ms increase in SAI QRST. In the subgroup of acutely decompensated HF patients (n = 35), a 10-fold increase in hsTnI was associated with a 61.0 (5.9-116.1) mV*ms increase in SAI QRST. Patient-specific time-varying changes in the surface ECG scalar measure of global electrical heterogeneity, as measured by SAI QRST, and in myocardial injury as measured by hsTnI, are independently and directly associated with each other, likely reflecting a common underlying mechanism. 2016 Wiley Periodicals, Inc.

  4. Coronary anatomy characteristics in patients with isolated right bundle branch block versus subjects with normal surface electrocardiogram.

    Science.gov (United States)

    Pakbaz, Marziyeh; Kazemisaeid, Ali; Yaminisharif, Ahmad; Davoodi, Gholamreza; Tokaldany, Masoumeh Lotfi; Hakki, Elham

    2013-03-01

    Isolated right bundle branch block is a common finding in the general population. It may be associated with variations in detailed coronary anatomy characteristics. The aim of this study was to investigate the coronary anatomy in patients with isolated right bundle branch block and to compare that with normal individuals. In this case-control study we investigated the coronary anatomy by reviewing angiographic films in two groups of normal coronary artery patients: patients with right bundle branch block (RBBB) (n = 92) and those with normal electrocardiograms (n = 184). There was no significant difference between the two groups in terms of diminutive left anterior descending artery, dominancy, number of obtuse marginal artery, diagonal, acute marginal artery, the position of the first septal versus diagonal branch, presence of ramus artery, and size of left main artery. The number of septal branches was higher in the case group (p-value right circulatory system was more common in both groups but cases showed more tendency to follow this pattern (p-value = 0.021). The frequency of the normal conus branch was higher in the cases versus controls (p-value = 0.009). Coronary anatomy characteristics are somewhat different in subjects with RBBB compared to normal individuals.

  5. A vector-based, 5-electrode, 12-lead monitoring ECG (EASI) is equivalent to conventional 12-lead ECG for diagnosis of acute coronary syndromes

    NARCIS (Netherlands)

    Wehr, Gabriele; Peters, Ron J.; Khalifé, Khalifé; Banning, Adrian P.; Kuehlkamp, Volker; Rickards, Anthony F.; Sechtem, Udo

    2006-01-01

    AIMS: The conventional 12-lead electrocardiogram (cECG) derived from 10 electrodes using a cardiograph is the gold standard for diagnosing myocardial ischemia. This study tested the hypothesis that a new 5-electrode 12-lead vector-based ECG (EASI; Philips Medical Systems, formerly Hewlett Packard

  6. Factors associated with failure to identify the culprit artery by the electrocardiogram in inferior ST-elevation myocardial infarction

    DEFF Research Database (Denmark)

    Tahvanainen, Minna; Nikus, Kjell C; Holmvang, Lene

    2011-01-01

    Right and left circumflex coronary artery occlusions cause inferior myocardial infarction. To improve the targeting of diagnostic and therapeutic measures individually, factors interfering with identification of the culprit artery by the electrocardiogram (ECG) were explored.......Right and left circumflex coronary artery occlusions cause inferior myocardial infarction. To improve the targeting of diagnostic and therapeutic measures individually, factors interfering with identification of the culprit artery by the electrocardiogram (ECG) were explored....

  7. Oyster Electrophysiology: Electrocardiogram Signal Recognition and Interpretation

    Directory of Open Access Journals (Sweden)

    Frederico M. Batista

    2015-06-01

    Full Text Available After 100 years of published recording traces pertaining to the oyster electrocardiogram (ECG, we revisited the original experiments of Eiger (1913, using state-of-the-art electrophysiology recorders. Our aim was to confirm that a recordable ECG, similar to that of higher vertebrates, is present in the oyster heart. Portuguese oysters Crassostrea angulata, collected from the Guadiana estuary, Portugal, were used. The oysters were drilled through the right valve to reveal the pericardium. Gold and silver electrodes were placed through the hole and electrophysiological recordings were obtained. Stimulation of the oyster heart was performed in vivo and in vitro using a constant current power supply. Placement of electrodes around the heart revealed a trace that very closely matched the published ECG of Eiger (1913. However, we were unable to confirm that the recording was an ECG of the oyster heart. Moreover, measurements on isolated oyster hearts revealed a low conductivity (0.10 S m‒1. We did, however, record a depolarization signal from what we believe to be the visceral ganglia, and this preceded contractions of the oyster heart. Our findings indicate that so-called ECGs, previously recorded by [2] in Ostrea edulis, but also the “ECG” recorded by [4] in C. virginica from oyster hearts, are in fact an artifact arising from relative movement of the recording electrodes, giving rise to a baseline shift that mimics in some ways the P and QRS features of a typical ECG. Nevertheless, such recordings provide information pertaining to heart rate and are not without importance.

  8. Atrial Fibrillation Predictors: Importance of the Electrocardiogram.

    Science.gov (United States)

    German, David M; Kabir, Muammar M; Dewland, Thomas A; Henrikson, Charles A; Tereshchenko, Larisa G

    2016-01-01

    Atrial fibrillation (AF) is the most common arrhythmia in adults and is associated with significant morbidity and mortality. Substantial interest has developed in the primary prevention of AF, and thus the identification of individuals at risk for developing AF. The electrocardiogram (ECG) provides a wealth of information, which is of value in predicting incident AF. The PR interval and P wave indices (including P wave duration, P wave terminal force, P wave axis, and other measures of P wave morphology) are discussed with regard to their ability to predict and characterize AF risk in the general population. The predictive value of the QT interval, ECG criteria for left ventricular hypertrophy, and findings of atrial and ventricular ectopy are also discussed. Efforts are underway to develop models that predict AF incidence in the general population; however, at present, little information from the ECG is included in these models. The ECG provides a great deal of information on AF risk and has the potential to contribute substantially to AF risk estimation, but more research is needed. © 2015 Wiley Periodicals, Inc.

  9. Teaching crucial skills: An electrocardiogram teaching module for medical students.

    Science.gov (United States)

    Chudgar, Saumil M; Engle, Deborah L; Grochowski, Colleen O'Connor; Gagliardi, Jane P

    2016-01-01

    Medical student performance in electrocardiogram (ECG) interpretation at our institution could be improved. Varied resources exist to teach students this essential skill. We created an ECG teaching module (ECGTM) of 75 cases representing 15 diagnoses to improve medical students' performance and confidence in ECG interpretation. Students underwent pre- and post-clerkship testing to assess ECG interpretation skills and confidence and also end-of-clinical-year testing in ECG and laboratory interpretation. Performance was compared for the years before and during ECGTM availability. Eighty-four percent of students (total n=101) reported using the ECGTM; 98% of those who used it reported it was useful. Students' performance and confidence were higher on the post-test. Students with access to the ECGTM (n=101) performed significantly better than students from the previous year (n=90) on the end-of-year ECG test. The continuous availability of an ECGTM was associated with improved confidence and ability in ECG interpretation. The ECGTM may be another available tool to help students as they learn to read ECGs. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Electrocardiogram signal denoising based on a new improved wavelet thresholding

    Science.gov (United States)

    Han, Guoqiang; Xu, Zhijun

    2016-08-01

    Good quality electrocardiogram (ECG) is utilized by physicians for the interpretation and identification of physiological and pathological phenomena. In general, ECG signals may mix various noises such as baseline wander, power line interference, and electromagnetic interference in gathering and recording process. As ECG signals are non-stationary physiological signals, wavelet transform is investigated to be an effective tool to discard noises from corrupted signals. A new compromising threshold function called sigmoid function-based thresholding scheme is adopted in processing ECG signals. Compared with other methods such as hard/soft thresholding or other existing thresholding functions, the new algorithm has many advantages in the noise reduction of ECG signals. It perfectly overcomes the discontinuity at ±T of hard thresholding and reduces the fixed deviation of soft thresholding. The improved wavelet thresholding denoising can be proved to be more efficient than existing algorithms in ECG signal denoising. The signal to noise ratio, mean square error, and percent root mean square difference are calculated to verify the denoising performance as quantitative tools. The experimental results reveal that the waves including P, Q, R, and S waves of ECG signals after denoising coincide with the original ECG signals by employing the new proposed method.

  11. 3-lead acquisition using single channel ECG device developed on AD8232 analog front end for wireless ECG application

    Science.gov (United States)

    Agung, Mochammad Anugrah; Basari

    2017-02-01

    Electrocardiogram (ECG) devices measure electrical activity of the heart muscle to determine heart conditions. ECG signal quality is the key factor in determining the diseases of the heart. This paper presents the design of 3-lead acquistion on single channel wireless ECG device developed on AD8232 chip platform using microcontroller. To make the system different from others, monopole antenna 2.4 GHz is used in order to send and receive ECG signal. The results show that the system still can receive ECG signal up to 15 meters by line of sight (LOS) condition. The shape of ECG signals is precisely similar with the expected signal, although some delays occur between two consecutive pulses. For further step, the system will be applied with on-body antenna in order to investigate body to body communication that will give variation in connectivity from the others.

  12. Motives for requesting an electrocardiogram in primary health care

    Directory of Open Access Journals (Sweden)

    Paulo Santos

    2015-05-01

    Full Text Available The management of requests for diagnostic exams presents its own inherent characteristics in primary health care and reflects the specific nature of the physician-patient relationship. The scope of the study was to identify the reasons for requesting an electrocardiogram (ECG in primary health care. A cross-sectional study was conducted in an urban region in Portugal, establishing the motives to ask for an ECG consecutively over two years, starting on 01/03/2007 using data retrieved from structured forms filled out by the physician at the moment of requesting the exam. A total of 870 ECGs of 817 patients were included. Symptoms manifested during the patient visit justified 48.5% of the ECGs, and follow-up of cardiovascular risk factors motivated 25.2%. A global health examination accounted for 22.8% of the requests. Multivariate analysis showed that the presence of symptoms (p

  13. Multi-purpose ECG telemetry system.

    Science.gov (United States)

    Marouf, Mohamed; Vukomanovic, Goran; Saranovac, Lazar; Bozic, Miroslav

    2017-06-19

    The Electrocardiogram ECG is one of the most important non-invasive tools for cardiac diseases diagnosis. Taking advantage of the developed telecommunication infrastructure, several approaches that address the development of telemetry cardiac devices were introduced recently. Telemetry ECG devices allow easy and fast ECG monitoring of patients with suspected cardiac issues. Choosing the right device with the desired working mode, signal quality, and the device cost are still the main obstacles to massive usage of these devices. In this paper, we introduce design, implementation, and validation of a multi-purpose telemetry system for recording, transmission, and interpretation of ECG signals in different recording modes. The system consists of an ECG device, a cloud-based analysis pipeline, and accompanied mobile applications for physicians and patients. The proposed ECG device's mechanical design allows laypersons to easily record post-event short-term ECG signals, using dry electrodes without any preparation. Moreover, patients can use the device to record long-term signals in loop and holter modes, using wet electrodes. In order to overcome the problem of signal quality fluctuation due to using different electrodes types and different placements on subject's chest, customized ECG signal processing and interpretation pipeline is presented for each working mode. We present the evaluation of the novel short-term recorder design. Recording of an ECG signal was performed for 391 patients using a standard 12-leads golden standard ECG and the proposed patient-activated short-term post-event recorder. In the validation phase, a sample of validation signals followed peer review process wherein two experts annotated the signals in terms of signal acceptability for diagnosis.We found that 96% of signals allow detecting arrhythmia and other signal's abnormal changes. Additionally, we compared and presented the correlation coefficient and the automatic QRS delineation results

  14. Pit-a-Pat: A Smart Electrocardiogram System for Detecting Arrhythmia.

    Science.gov (United States)

    Park, Juyoung; Lee, Kuyeon; Kang, Kyungtae

    2015-10-01

    Electrocardiogram (ECG) telemonitoring is one of the most promising applications of medical telemetry. However, previous approaches to ECG telemonitoring have largely relied on public databases of ECG results. In this article we propose a smart ECG system called Pit-a-Pat, which extracts features from ECG signals and detects arrhythmia. It is designed to run on an Android™ (Google, Mountain View, CA) device, without requiring modifications to other software. We implemented the Pit-a-Pat system using a commercial ECG device, and the experimental results demonstrate the effectiveness and accuracy of Pit-a-Pat for monitoring the ECG signal and analyzing the cardiac activity of a mobile patient. The proposed system allows monitoring of cardiac activity with automatic analysis, thereby providing a convenient, inexpensive, and ubiquitous adjunct to personal healthcare.

  15. Applicability of initial optimal maternal and fetal electrocardiogram combination vectors to subsequent recordings

    International Nuclear Information System (INIS)

    Yan Hua-Wen; Huang Xiao-Lin; Zhao Ying; Si Jun-Feng; Liu Hong-Xing; Liu Tie-Bing

    2014-01-01

    A series of experiments are conducted to confirm whether the vectors calculated for an early section of a continuous non-invasive fetal electrocardiogram (fECG) recording can be directly applied to subsequent sections in order to reduce the computation required for real-time monitoring. Our results suggest that it is generally feasible to apply the initial optimal maternal and fetal ECG combination vectors to extract the fECG and maternal ECG in subsequent recorded sections. (interdisciplinary physics and related areas of science and technology)

  16. [Research on electrocardiogram de-noising algorithm based on wavelet neural networks].

    Science.gov (United States)

    Wan, Xiangkui; Zhang, Jun

    2010-12-01

    In this paper, the ECG de-noising technology based on wavelet neural networks (WNN) is used to deal with the noises in Electrocardiogram (ECG) signal. The structure of WNN, which has the outstanding nonlinear mapping capability, is designed as a nonlinear filter used for ECG to cancel the baseline wander, electromyo-graphical interference and powerline interference. The network training algorithm and de-noising experiments results are presented, and some key points of the WNN filter using ECG de-noising are discussed.

  17. A randomized control trial comparing use of a novel electrocardiogram simulator with traditional teaching in the acquisition of electrocardiogram interpretation skill.

    Science.gov (United States)

    Fent, Graham; Gosai, Jivendra; Purva, Makani

    2016-01-01

    Accurate interpretation of the electrocardiogram (ECG) remains an essential skill for medical students and junior doctors. While many techniques for teaching ECG interpretation are described, no single method has been shown to be superior. This randomized control trial is the first to investigate whether teaching ECG interpretation using a computer simulator program or traditional teaching leads to improved scores in a test of ECG interpretation among medical students and postgraduate doctors immediately after and 3months following teaching. Participants' opinions of the program were assessed using a questionnaire. There were no differences in ECG interpretation test scores immediately after or 3months after teaching in the lecture or simulator groups. At present therefore, there is insufficient evidence to suggest that ECG simulator programs are superior to traditional teaching. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. ECG Sensor Card with Evolving RBP Algorithms for Human Verification.

    Science.gov (United States)

    Tseng, Kuo-Kun; Huang, Huang-Nan; Zeng, Fufu; Tu, Shu-Yi

    2015-08-21

    It is known that cardiac and respiratory rhythms in electrocardiograms (ECGs) are highly nonlinear and non-stationary. As a result, most traditional time-domain algorithms are inadequate for characterizing the complex dynamics of the ECG. This paper proposes a new ECG sensor card and a statistical-based ECG algorithm, with the aid of a reduced binary pattern (RBP), with the aim of achieving faster ECG human identity recognition with high accuracy. The proposed algorithm has one advantage that previous ECG algorithms lack-the waveform complex information and de-noising preprocessing can be bypassed; therefore, it is more suitable for non-stationary ECG signals. Experimental results tested on two public ECG databases (MIT-BIH) from MIT University confirm that the proposed scheme is feasible with excellent accuracy, low complexity, and speedy processing. To be more specific, the advanced RBP algorithm achieves high accuracy in human identity recognition and is executed at least nine times faster than previous algorithms. Moreover, based on the test results from a long-term ECG database, the evolving RBP algorithm also demonstrates superior capability in handling long-term and non-stationary ECG signals.

  19. Noninvasive recording of electrocardiogram in conscious rat: A new device.

    Science.gov (United States)

    Kumar, Pradeep; Srivastava, Pooja; Gupta, Ankit; Bajpai, Manish

    2017-01-01

    Electrocardiogram (ECG) is an important tool for the study of cardiac electrophysiology both in human beings and experimental animals. Existing methods of ECG recording in small animals like rat have several limitations and ECG recordings of the anesthetized rat lack validity for heart rate (HR) variability analysis. The aim of the present study was to validate the ECG data from new device with ECG of anesthetized rat. The ECG was recorded on student's physiograph (BioDevice, Ambala) and suitable coupler and electrodes in six animals first by the newly developed device in conscious state and second in anesthetized state (stabilized technique). The data obtained were analyzed using unpaired t -test showed no significant difference ( P < 0.05) in QTc, QRS, and HR recorded by new device and established device in rats. No previous study describes a similar ECG recording in conscious state of rats. Thus, the present method may be a most physiological and inexpensive alternative to other methods. In this study, the animals were not restrained; they were just secured and represent a potential strength of the study.

  20. Assessment of the electrocardiogram in dogs with visceral leishmaniasis

    Directory of Open Access Journals (Sweden)

    Marlos G. Sousa

    2013-05-01

    Full Text Available As myocarditis and arrhythmias have been shown to occur in both human beings and dogs with leishmaniasis, electrocardiograms of 105 dogs serologically positive for this disease were assessed for rhythm disturbances and changes in ECG waves. A few expressive alterations were seen, including sinus arrest, right bundle branch block, and atrial premature beats in 14.3%, 4.8%, and 4.8% of the studied subjects, respectively. Also, the analysis of ECG waves showed changes suggestive of left atrium and ventricle enlargements, and myocardial hypoxia in some animals. Although cardiac compromise has been previously reported in dogs with leishmaniasis, only a small subset of dogs showed any alteration in the electrocardiogram, which cannot support the occurrence of myocarditis in this investigation.

  1. Are ECG abnormalities in Noonan syndrome characteristic for the syndrome?

    NARCIS (Netherlands)

    Raaijmakers, R.; Noordam, C.; Noonan, J.A.; Croonen, E.A.; Burgt, C.J. van der; Draaisma, J.M.T.

    2008-01-01

    Of all patients with Noonan syndrome, 50-90% have one or more congenital heart defects. The most frequent occurring are pulmonary stenosis (PS) and hypertrophic cardiomyopathy. The electrocardiogram (ECG) of a patient with Noonan syndrome often shows a characteristic pattern, with a left axis

  2. Cardiac Electrophysiology: Normal and Ischemic Ionic Currents and the ECG

    Science.gov (United States)

    Klabunde, Richard E.

    2017-01-01

    Basic cardiac electrophysiology is foundational to understanding normal cardiac function in terms of rate and rhythm and initiation of cardiac muscle contraction. The primary clinical tool for assessing cardiac electrical events is the electrocardiogram (ECG), which provides global and regional information on rate, rhythm, and electrical…

  3. How to read an electrocardiogram (ECG). Part 2:Abnormalities of ...

    African Journals Online (AJOL)

    Ann Burgess

    Electrical conduction and its abnormalities. Contraction of the heart muscle occurs in response to electrical depolarisation – the rapid spread of electrical activity throughout the myocardium which is facilitated by specialised conduction tissue. This process normally begins with spontaneous depolarisation of cells in the sinus ...

  4. Extraction of fetal electrocardiogram (ECG) by extended state ...

    Indian Academy of Sciences (India)

    Fetal heart rate (FHR) monitoring is a routine work for obtaining significant information about the fetal condition during pregnancy and labor. During pregnancy, the motivation for monitoring the fetal is to recognize pathological conditions, typically asphyxia with sufficient warning to enable intervention by the clinician.

  5. A new algorithm to diagnose atrial ectopic origin from multi lead ECG systems--insights from 3D virtual human atria and torso.

    Directory of Open Access Journals (Sweden)

    Erick A Perez Alday

    2015-01-01

    Full Text Available Rapid atrial arrhythmias such as atrial fibrillation (AF predispose to ventricular arrhythmias, sudden cardiac death and stroke. Identifying the origin of atrial ectopic activity from the electrocardiogram (ECG can help to diagnose the early onset of AF in a cost-effective manner. The complex and rapid atrial electrical activity during AF makes it difficult to obtain detailed information on atrial activation using the standard 12-lead ECG alone. Compared to conventional 12-lead ECG, more detailed ECG lead configurations may provide further information about spatio-temporal dynamics of the body surface potential (BSP during atrial excitation. We apply a recently developed 3D human atrial model to simulate electrical activity during normal sinus rhythm and ectopic pacing. The atrial model is placed into a newly developed torso model which considers the presence of the lungs, liver and spinal cord. A boundary element method is used to compute the BSP resulting from atrial excitation. Elements of the torso mesh corresponding to the locations of the placement of the electrodes in the standard 12-lead and a more detailed 64-lead ECG configuration were selected. The ectopic focal activity was simulated at various origins across all the different regions of the atria. Simulated BSP maps during normal atrial excitation (i.e. sinoatrial node excitation were compared to those observed experimentally (obtained from the 64-lead ECG system, showing a strong agreement between the evolution in time of the simulated and experimental data in the P-wave morphology of the ECG and dipole evolution. An algorithm to obtain the location of the stimulus from a 64-lead ECG system was developed. The algorithm presented had a success rate of 93%, meaning that it correctly identified the origin of atrial focus in 75/80 simulations, and involved a general approach relevant to any multi-lead ECG system. This represents a significant improvement over previously developed

  6. ECG Signal Analysis and Arrhythmia Detection using Wavelet Transform

    Science.gov (United States)

    Kaur, Inderbir; Rajni, Rajni; Marwaha, Anupma

    2016-12-01

    Electrocardiogram (ECG) is used to record the electrical activity of the heart. The ECG signal being non-stationary in nature, makes the analysis and interpretation of the signal very difficult. Hence accurate analysis of ECG signal with a powerful tool like discrete wavelet transform (DWT) becomes imperative. In this paper, ECG signal is denoised to remove the artifacts and analyzed using Wavelet Transform to detect the QRS complex and arrhythmia. This work is implemented in MATLAB software for MIT/BIH Arrhythmia database and yields the sensitivity of 99.85 %, positive predictivity of 99.92 % and detection error rate of 0.221 % with wavelet transform. It is also inferred that DWT outperforms principle component analysis technique in detection of ECG signal.

  7. A Novel Automatic Detection System for ECG Arrhythmias Using Maximum Margin Clustering with Immune Evolutionary Algorithm

    Directory of Open Access Journals (Sweden)

    Bohui Zhu

    2013-01-01

    Full Text Available This paper presents a novel maximum margin clustering method with immune evolution (IEMMC for automatic diagnosis of electrocardiogram (ECG arrhythmias. This diagnostic system consists of signal processing, feature extraction, and the IEMMC algorithm for clustering of ECG arrhythmias. First, raw ECG signal is processed by an adaptive ECG filter based on wavelet transforms, and waveform of the ECG signal is detected; then, features are extracted from ECG signal to cluster different types of arrhythmias by the IEMMC algorithm. Three types of performance evaluation indicators are used to assess the effect of the IEMMC method for ECG arrhythmias, such as sensitivity, specificity, and accuracy. Compared with K-means and iterSVR algorithms, the IEMMC algorithm reflects better performance not only in clustering result but also in terms of global search ability and convergence ability, which proves its effectiveness for the detection of ECG arrhythmias.

  8. Limited Evidence for Risk Factors for Proarrhythmia and Sudden Cardiac Death in Patients Using Antidepressants: Dutch Consensus on ECG Monitoring

    NARCIS (Netherlands)

    Simoons, M. (Mirjam); K.A. Seldenrijk (Kees); H. Mulder (Hans); T.K. Birkenhäger (Tom); Groothedde-Kuyvenhoven, M. (Mascha); Kok, R. (Rob); C. Kramers; W. Verbeeck (Wim); Westra, M. (Mirjam); E.N. van Roon (Eric); Bakker, R. (Roberto); H.G. Ruhé (Henricus G.Eric)

    2018-01-01

    textabstractCurrently, there is a lack of international and national guidelines or consensus documents with specific recommendations for electrocardiogram (ECG) screening and monitoring during antidepressant treatment. To make a proper estimation of the risk of cardiac arrhythmias and sudden

  9. ECG telemetry in conscious guinea pigs.

    Science.gov (United States)

    Ruppert, Sabine; Vormberge, Thomas; Igl, Bernd-Wolfgang; Hoffmann, Michael

    2016-01-01

    During preclinical drug development, monitoring of the electrocardiogram (ECG) is an important part of cardiac safety assessment. To detect potential pro-arrhythmic liabilities of a drug candidate and for internal decision-making during early stage drug development an in vivo model in small animals with translatability to human cardiac function is required. Over the last years, modifications/improvements regarding animal housing, ECG electrode placement, and data evaluation have been introduced into an established model for ECG recordings using telemetry in conscious, freely moving guinea pigs. Pharmacological validation using selected reference compounds affecting different mechanisms relevant for cardiac electrophysiology (quinidine, flecainide, atenolol, dl-sotalol, dofetilide, nifedipine, moxifloxacin) was conducted and findings were compared with results obtained in telemetered Beagle dogs. Under standardized conditions, reliable ECG data with low variability allowing largely automated evaluation were obtained from the telemetered guinea pig model. The model is sensitive to compounds blocking cardiac sodium channels, hERG K(+) channels and calcium channels, and appears to be even more sensitive to β-blockers as observed in dogs at rest. QT interval correction according to Bazett and Sarma appears to be appropriate methods in conscious guinea pigs. Overall, the telemetered guinea pig is a suitable model for the conduct of early stage preclinical ECG assessment. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Electrocardiogram Signal Denoising Using Extreme-Point Symmetric Mode Decomposition and Nonlocal Means

    Directory of Open Access Journals (Sweden)

    Xiaoying Tian

    2016-09-01

    Full Text Available Electrocardiogram (ECG signals contain a great deal of essential information which can be utilized by physicians for the diagnosis of heart diseases. Unfortunately, ECG signals are inevitably corrupted by noise which will severely affect the accuracy of cardiovascular disease diagnosis. Existing ECG signal denoising methods based on wavelet shrinkage, empirical mode decomposition and nonlocal means (NLM cannot provide sufficient noise reduction or well-detailed preservation, especially with high noise corruption. To address this problem, we have proposed a hybrid ECG signal denoising scheme by combining extreme-point symmetric mode decomposition (ESMD with NLM. In the proposed method, the noisy ECG signals will first be decomposed into several intrinsic mode functions (IMFs and adaptive global mean using ESMD. Then, the first several IMFs will be filtered by the NLM method according to the frequency of IMFs while the QRS complex detected from these IMFs as the dominant feature of the ECG signal and the remaining IMFs will be left unprocessed. The denoised IMFs and unprocessed IMFs are combined to produce the final denoised ECG signals. Experiments on both simulated ECG signals and real ECG signals from the MIT-BIH database demonstrate that the proposed method can suppress noise in ECG signals effectively while preserving the details very well, and it outperforms several state-of-the-art ECG signal denoising methods in terms of signal-to-noise ratio (SNR, root mean squared error (RMSE, percent root mean square difference (PRD and mean opinion score (MOS error index.

  11. Electrocardiogram pearl: ST-T changes in patient with chest pain – Ischemia or infarction?

    Directory of Open Access Journals (Sweden)

    Parminder Singh Manghera

    2017-01-01

    Full Text Available Most common electrocardiogram (ECG findings of myocardial ischemia are ST segment deviations & T wave (ST-T alterations. However, multiple other conditions can cause ST-T changes mimicking ischemia including ventricular hypertrophy, bundle branch block, electrolyte imbalance, drugs, channelopathies, etc. Uncommonly, incorrect placement of limb leads can also produce ST-T changes leading to diagnostic dilemma. We report a case of erroneous limb-lead placement in a 45 years male mimicking ischemic ECG changes.

  12. Unmasking Brugada-type electrocardiogram on deep inspiration.

    Science.gov (United States)

    Yamawake, Noriyoshi; Nishizaki, Mitsuhiro; Shimizu, Masato; Fujii, Hiroyuki; Sakurada, Harumizu; Hiraoka, Masayasu

    2014-01-01

    Electrocardiogram (ECG) recorded at the upper intercostal lead positions is recommended as an additional diagnostic clue for Brugada syndrome (BrS), but similar recording conditions to unmask ECG signs have not been explored. We evaluated the diagnostic usefulness for unmasking ECG signs of BrS using recordings at the upper intercostal lead position, on deep inspiration and on standing. In 34 patients (mean age, 49±14 years; 30 male) with diagnosed and suspected BrS, ECG type and ST-elevation in leads V1-V3 recorded at a higher position by 1 rib from the standard position (3ICS), and at standard lead positions (4ICS) on deep inspiration (DI test) and on standing (Stand test) were compared with the conventional lead positions (baseline). While type 1 ECG had been documented in 17 of 34 patients on at least 1 occasion in the past, only 4 had the sign at baseline during the study. Twenty patients had type 1 on 3ICS recording, 18 on DI test, and 6 on Stand test. Among 17 patients without previous documentation of spontaneous type 1, 7 had type 1 on 3ICS recording, 6 on DI test, and 1 on Stand test. ECG recording on deep inspiration is useful to unmask diagnostic signs of BrS and has similar accuracy to 3ICS recording.  

  13. Dynamic conduction and repolarisation changes in early arrhythmogenic right ventricular cardiomyopathy versus benign outflow tract ectopy demonstrated by high density mapping & paced surface ECG analysis.

    Science.gov (United States)

    Finlay, Malcolm C; Ahmed, Akbar K; Sugrue, Alan; Bhar-Amato, Justine; Quarta, Giovanni; Pantazis, Antonis; Ciaccio, Edward J; Syrris, Petros; Sen-Chowdhry, Srijita; Ben-Simon, Ron; Chow, Anthony W; Lowe, Martin D; Segal, Oliver R; McKenna, William J; Lambiase, Pier D

    2014-01-01

    The concealed phase of arrhythmogenic right ventricular cardiomyopathy (ARVC) may initially manifest electrophysiologically. No studies have examined dynamic conduction/repolarization kinetics to distinguish benign right ventricular outflow tract ectopy (RVOT ectopy) from ARVC's early phase. We investigated dynamic endocardial electrophysiological changes that differentiate early ARVC disease expression from RVOT ectopy. 22 ARVC (12 definite based upon family history and mutation carrier status, 10 probable) patients without right ventricular structural anomalies underwent high-density non-contact mapping of the right ventricle. These were compared to data from 14 RVOT ectopy and 12 patients with supraventricular tachycardias and normal hearts. Endocardial & surface ECG conduction and repolarization parameters were assessed during a standard S1-S2 restitution protocol. Definite ARVC without RV structural disease could not be clearly distinguished from RVOT ectopy during sinus rhythm or during steady state pacing. Delay in Activation Times at coupling intervals just above the ventricular effective refractory period (VERP) increased in definite ARVC (43 ± 20 ms) more than RVOT ectopy patients (36 ± 14 ms, p = 0.03) or Normals (25 ± 16 ms, p = 0.008) and a progressive separation of the repolarisation time curves between groups existed. Repolarization time increases in the RVOT were also greatest in ARVC (definite ARVC: 18 ± 20 ms; RVOT ectopy: 5 ± 14, Normal: 1 ± 18, pSurface ECG correlates of these intracardiac measurements demonstrated an increase of greater than 48 ms in stimulus to surface ECG J-point pre-ERP versus steady state, with an 88% specificity and 68% sensitivity in distinguishing definite ARVC from the other groups. This technique could not distinguish patients with genetic predisposition to ARVC only (probable ARVC) from controls. Significant changes in dynamic conduction and repolarization are apparent in early ARVC before detectable RV

  14. An Algorithm for Filtering Electrocardiograms to Improve Nonlinear Feature Extraction

    Directory of Open Access Journals (Sweden)

    Mohammad Bahmanyar

    2007-04-01

    Full Text Available This paper introduces an algorithm for removing high frequency noise components from electrocardiograms (ECGs based on Savitzky-Golay finite duration impulse response (FIR smoothing filter. The peaks of R waves and the points at which Q waves end and S waves start are detected for all beats. These points are used to separate the low amplitude parts of the ECG in each beat, which are most affected by high frequency noise. The Savitzky-Golay smoothing algorithm is then applied to these parts of the ECG and the resultant filtered signals are added back to their corresponding QRS parts. The effect of high frequency noise removal on nonlinear features such as largest Lyapunov exponent and minimum embedding dimension is also investigated. Performance of the filter has been compared with an equiripple low pass filter and wavelet de-noising.

  15. Classification of hydration status using electrocardiogram and machine learning

    Science.gov (United States)

    Kaveh, Anthony; Chung, Wayne

    2013-10-01

    The electrocardiogram (ECG) has been used extensively in clinical practice for decades to non-invasively characterize the health of heart tissue; however, these techniques are limited to time domain features. We propose a machine classification system using support vector machines (SVM) that uses temporal and spectral information to classify health state beyond cardiac arrhythmias. Our method uses single lead ECG to classify volume depletion (or dehydration) without the lengthy and costly blood analysis tests traditionally used for detecting dehydration status. Our method builds on established clinical ECG criteria for identifying electrolyte imbalances and lends to automated, computationally efficient implementation. The method was tested on the MIT-BIH PhysioNet database to validate this purely computational method for expedient disease-state classification. The results show high sensitivity, supporting use as a cost- and time-effective screening tool.

  16. Validity of the surface electrocardiogram criteria for right ventricular hypertrophy: the MESA-RV Study (Multi-Ethnic Study of Atherosclerosis-Right Ventricle).

    Science.gov (United States)

    Whitman, Isaac R; Patel, Vickas V; Soliman, Elsayed Z; Bluemke, David A; Praestgaard, Amy; Jain, Aditya; Herrington, David; Lima, Joao A C; Kawut, Steven M

    2014-02-25

    The study aimed to assess the diagnostic properties of electrocardiographic (ECG) criteria for right ventricular hypertrophy (RVH) measured by cardiac magnetic resonance imaging (cMRI) in adults without clinical cardiovascular disease. Current ECG criteria for RVH were based on cadaveric dissection in small studies. MESA (Multi-Ethnic Study of Atherosclerosis) performed cMRIs with complete right ventricle (RV) interpretation on 4,062 participants without clinical cardiovascular disease. Endocardial margins of the RV were manually contoured on diastolic and systolic images. The ECG screening criteria for RVH from the 2009 American Heart Association Recommendations for Standardization and Interpretation of the ECG were examined in participants with and without left ventricular (LV) hypertrophy or reduced ejection fraction. RVH was defined using sex-specific normative equations based on age, height, and weight. The study sample with normal LV morphology and function (n = 3,719) was age 61.3 ± 10.0 years, 53.5% female, 39.6% Caucasian, 25.5% African American, 21.9% Hispanic, and 13.0% Asian. The mean body mass index was 27.9 ± 5.0 kg/m(2). A total of 6% had RVH, which was generally mild. Traditional ECG criteria were specific (many >95%) but had low sensitivity for RVH by cMRI. The positive predictive values were not sufficiently high as to be clinically useful (maximum 12%). The results did not differ based on age, sex, race, or smoking status, or with the inclusion of participants with abnormal LV mass or function. Classification and regression tree analysis revealed that no combination of ECG variables was better than the criteria used singly. The recommended ECG screening criteria for RVH are not sufficiently sensitive or specific for screening for mild RVH in adults without clinical cardiovascular disease. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  17. Designing ECG-based physical unclonable function for security of wearable devices.

    Science.gov (United States)

    Shihui Yin; Chisung Bae; Sang Joon Kim; Jae-Sun Seo

    2017-07-01

    As a plethora of wearable devices are being introduced, significant concerns exist on the privacy and security of personal data stored on these devices. Expanding on recent works of using electrocardiogram (ECG) as a modality for biometric authentication, in this work, we investigate the possibility of using personal ECG signals as the individually unique source for physical unclonable function (PUF), which eventually can be used as the key for encryption and decryption engines. We present new signal processing and machine learning algorithms that learn and extract maximally different ECG features for different individuals and minimally different ECG features for the same individual over time. Experimental results with a large 741-subject in-house ECG database show that the distributions of the intra-subject (same person) Hamming distance of extracted ECG features and the inter-subject Hamming distance have minimal overlap. 256-b random numbers generated from the ECG features of 648 (out of 741) subjects pass the NIST randomness tests.

  18. Design and validation of a three-instrument toolkit for the assessment of competence in electrocardiogram rhythm recognition.

    Science.gov (United States)

    Hernández-Padilla, José M; Granero-Molina, José; Márquez-Hernández, Verónica V; Suthers, Fiona; López-Entrambasaguas, Olga M; Fernández-Sola, Cayetano

    2017-06-01

    Rapid and accurate interpretation of cardiac arrhythmias by nurses has been linked with safe practice and positive patient outcomes. Although training in electrocardiogram rhythm recognition is part of most undergraduate nursing programmes, research continues to suggest that nurses and nursing students lack competence in recognising cardiac rhythms. In order to promote patient safety, nursing educators must develop valid and reliable assessment tools that allow the rigorous assessment of this competence before nursing students are allowed to practise without supervision. The aim of this study was to develop and psychometrically evaluate a toolkit to holistically assess competence in electrocardiogram rhythm recognition. Following a convenience sampling technique, 293 nursing students from a nursing faculty in a Spanish university were recruited for the study. The following three instruments were developed and psychometrically tested: an electrocardiogram knowledge assessment tool (ECG-KAT), an electrocardiogram skills assessment tool (ECG-SAT) and an electrocardiogram self-efficacy assessment tool (ECG-SES). Reliability and validity (content, criterion and construct) of these tools were meticulously examined. A high Cronbach's alpha coefficient demonstrated the excellent reliability of the instruments (ECG-KAT=0.89; ECG-SAT=0.93; ECG-SES=0.98). An excellent context validity index (scales' average content validity index>0.94) and very good criterion validity were evidenced for all the tools. Regarding construct validity, principal component analysis revealed that all items comprising the instruments contributed to measure knowledge, skills or self-efficacy in electrocardiogram rhythm recognition. Moreover, known-groups analysis showed the tools' ability to detect expected differences in competence between groups with different training experiences. The three-instrument toolkit developed showed excellent psychometric properties for measuring competence in

  19. Biometric and Emotion Identification: An ECG Compression Based Method

    Directory of Open Access Journals (Sweden)

    Susana Brás

    2018-04-01

    Full Text Available We present an innovative and robust solution to both biometric and emotion identification using the electrocardiogram (ECG. The ECG represents the electrical signal that comes from the contraction of the heart muscles, indirectly representing the flow of blood inside the heart, it is known to convey a key that allows biometric identification. Moreover, due to its relationship with the nervous system, it also varies as a function of the emotional state. The use of information-theoretic data models, associated with data compression algorithms, allowed to effectively compare ECG records and infer the person identity, as well as emotional state at the time of data collection. The proposed method does not require ECG wave delineation or alignment, which reduces preprocessing error. The method is divided into three steps: (1 conversion of the real-valued ECG record into a symbolic time-series, using a quantization process; (2 conditional compression of the symbolic representation of the ECG, using the symbolic ECG records stored in the database as reference; (3 identification of the ECG record class, using a 1-NN (nearest neighbor classifier. We obtained over 98% of accuracy in biometric identification, whereas in emotion recognition we attained over 90%. Therefore, the method adequately identify the person, and his/her emotion. Also, the proposed method is flexible and may be adapted to different problems, by the alteration of the templates for training the model.

  20. Biometric and Emotion Identification: An ECG Compression Based Method.

    Science.gov (United States)

    Brás, Susana; Ferreira, Jacqueline H T; Soares, Sandra C; Pinho, Armando J

    2018-01-01

    We present an innovative and robust solution to both biometric and emotion identification using the electrocardiogram (ECG). The ECG represents the electrical signal that comes from the contraction of the heart muscles, indirectly representing the flow of blood inside the heart, it is known to convey a key that allows biometric identification. Moreover, due to its relationship with the nervous system, it also varies as a function of the emotional state. The use of information-theoretic data models, associated with data compression algorithms, allowed to effectively compare ECG records and infer the person identity, as well as emotional state at the time of data collection. The proposed method does not require ECG wave delineation or alignment, which reduces preprocessing error. The method is divided into three steps: (1) conversion of the real-valued ECG record into a symbolic time-series, using a quantization process; (2) conditional compression of the symbolic representation of the ECG, using the symbolic ECG records stored in the database as reference; (3) identification of the ECG record class, using a 1-NN (nearest neighbor) classifier. We obtained over 98% of accuracy in biometric identification, whereas in emotion recognition we attained over 90%. Therefore, the method adequately identify the person, and his/her emotion. Also, the proposed method is flexible and may be adapted to different problems, by the alteration of the templates for training the model.

  1. Empirical mode decomposition of the ECG signal for noise removal

    Science.gov (United States)

    Khan, Jesmin; Bhuiyan, Sharif; Murphy, Gregory; Alam, Mohammad

    2011-04-01

    Electrocardiography is a diagnostic procedure for the detection and diagnosis of heart abnormalities. The electrocardiogram (ECG) signal contains important information that is utilized by physicians for the diagnosis and analysis of heart diseases. So good quality ECG signal plays a vital role for the interpretation and identification of pathological, anatomical and physiological aspects of the whole cardiac muscle. However, the ECG signals are corrupted by noise which severely limit the utility of the recorded ECG signal for medical evaluation. The most common noise presents in the ECG signal is the high frequency noise caused by the forces acting on the electrodes. In this paper, we propose a new ECG denoising method based on the empirical mode decomposition (EMD). The proposed method is able to enhance the ECG signal upon removing the noise with minimum signal distortion. Simulation is done on the MIT-BIH database to verify the efficacy of the proposed algorithm. Experiments show that the presented method offers very good results to remove noise from the ECG signal.

  2. Preoperative Electrocardiogram Score for Predicting New-Onset Postoperative Atrial Fibrillation in Patients Undergoing Cardiac Surgery.

    Science.gov (United States)

    Gu, Jiwei; Andreasen, Jan J; Melgaard, Jacob; Lundbye-Christensen, Søren; Hansen, John; Schmidt, Erik B; Thorsteinsson, Kristinn; Graff, Claus

    2017-02-01

    To investigate if electrocardiogram (ECG) markers from routine preoperative ECGs can be used in combination with clinical data to predict new-onset postoperative atrial fibrillation (POAF) following cardiac surgery. Retrospective observational case-control study. Single-center university hospital. One hundred consecutive adult patients (50 POAF, 50 without POAF) who underwent coronary artery bypass grafting, valve surgery, or combinations. Retrospective review of medical records and registration of POAF. Clinical data and demographics were retrieved from the Western Denmark Heart Registry and patient records. Paper tracings of preoperative ECGs were collected from patient records, and ECG measurements were read by two independent readers blinded to outcome. A subset of four clinical variables (age, gender, body mass index, and type of surgery) were selected to form a multivariate clinical prediction model for POAF and five ECG variables (QRS duration, PR interval, P-wave duration, left atrial enlargement, and left ventricular hypertrophy) were used in a multivariate ECG model. Adding ECG variables to the clinical prediction model significantly improved the area under the receiver operating characteristic curve from 0.54 to 0.67 (with cross-validation). The best predictive model for POAF was a combined clinical and ECG model with the following four variables: age, PR-interval, QRS duration, and left atrial enlargement. ECG markers obtained from a routine preoperative ECG may be helpful in predicting new-onset POAF in patients undergoing cardiac surgery. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Application of artificial neural networks for versatile preprocessing of electrocardiogram recordings.

    Science.gov (United States)

    Mateo, J; Rieta, J J

    2012-02-01

    The electrocardiogram (ECG) is the most widely used method for diagnosis of heart diseases, where a good quality of recordings allows the proper interpretation and identification of physiological and pathological phenomena. However, ECG recordings often have interference from noises including thermal, muscle, baseline and powerline noises. These signals severely limit ECG recording utility and, hence, have to be removed. To deal with this problem, the present paper proposes an artificial neural network (ANN) as a filter to remove all kinds of noise in just one step. The method is based on a growing ANN which optimizes both the number of nodes in the hidden layer and the coefficient matrices, which are optimized by means of the Widrow-Hoff delta algorithm. The ANN has been trained with a database comprising all kinds of noise, both from synthesized and real ECG recordings, in order to handle any noise signal present in the ECG. The proposed system improves results yielded by conventional techniques of ECG filtering, such as FIR-based systems, adaptive filtering and wavelet filtering. Therefore, the algorithm could serve as an effective framework to substantially reduce noise in ECG recordings. In addition, the resulting ECG signal distortion is notably more reduced in comparison with conventional methodologies. In summary, the current contribution introduces a new method which is able to suppress all ECG interference signals in only one step with low ECG distortion and a high noise reduction.

  4. [Synchronous playing and acquiring of heart sounds and electrocardiogram based on labVIEW].

    Science.gov (United States)

    Dan, Chunmei; He, Wei; Zhou, Jing; Que, Xiaosheng

    2008-12-01

    In this paper is described a comprehensive system, which can acquire heart sounds and electrocardiogram (ECG) in parallel, synchronize the display; and play of heart sound and make auscultation and check phonocardiogram to tie in. The hardware system with C8051F340 as the core acquires the heart sound and ECG synchronously, and then sends them to indicators, respectively. Heart sounds are displayed and played simultaneously by controlling the moment of writing to indicator and sound output device. In clinical testing, heart sounds can be successfully located with ECG and real-time played.

  5. Sequential Total Variation Denoising for the Extraction of Fetal ECG from Single-Channel Maternal Abdominal ECG.

    Science.gov (United States)

    Lee, Kwang Jin; Lee, Boreom

    2016-07-01

    Fetal heart rate (FHR) is an important determinant of fetal health. Cardiotocography (CTG) is widely used for measuring the FHR in the clinical field. However, fetal movement and blood flow through the maternal blood vessels can critically influence Doppler ultrasound signals. Moreover, CTG is not suitable for long-term monitoring. Therefore, researchers have been developing algorithms to estimate the FHR using electrocardiograms (ECGs) from the abdomen of pregnant women. However, separating the weak fetal ECG signal from the abdominal ECG signal is a challenging problem. In this paper, we propose a method for estimating the FHR using sequential total variation denoising and compare its performance with that of other single-channel fetal ECG extraction methods via simulation using the Fetal ECG Synthetic Database (FECGSYNDB). Moreover, we used real data from PhysioNet fetal ECG databases for the evaluation of the algorithm performance. The R-peak detection rate is calculated to evaluate the performance of our algorithm. Our approach could not only separate the fetal ECG signals from the abdominal ECG signals but also accurately estimate the FHR.

  6. Sequential Total Variation Denoising for the Extraction of Fetal ECG from Single-Channel Maternal Abdominal ECG

    Directory of Open Access Journals (Sweden)

    Kwang Jin Lee

    2016-07-01

    Full Text Available Fetal heart rate (FHR is an important determinant of fetal health. Cardiotocography (CTG is widely used for measuring the FHR in the clinical field. However, fetal movement and blood flow through the maternal blood vessels can critically influence Doppler ultrasound signals. Moreover, CTG is not suitable for long-term monitoring. Therefore, researchers have been developing algorithms to estimate the FHR using electrocardiograms (ECGs from the abdomen of pregnant women. However, separating the weak fetal ECG signal from the abdominal ECG signal is a challenging problem. In this paper, we propose a method for estimating the FHR using sequential total variation denoising and compare its performance with that of other single-channel fetal ECG extraction methods via simulation using the Fetal ECG Synthetic Database (FECGSYNDB. Moreover, we used real data from PhysioNet fetal ECG databases for the evaluation of the algorithm performance. The R-peak detection rate is calculated to evaluate the performance of our algorithm. Our approach could not only separate the fetal ECG signals from the abdominal ECG signals but also accurately estimate the FHR.

  7. Sequential Total Variation Denoising for the Extraction of Fetal ECG from Single-Channel Maternal Abdominal ECG

    Science.gov (United States)

    Lee, Kwang Jin; Lee, Boreom

    2016-01-01

    Fetal heart rate (FHR) is an important determinant of fetal health. Cardiotocography (CTG) is widely used for measuring the FHR in the clinical field. However, fetal movement and blood flow through the maternal blood vessels can critically influence Doppler ultrasound signals. Moreover, CTG is not suitable for long-term monitoring. Therefore, researchers have been developing algorithms to estimate the FHR using electrocardiograms (ECGs) from the abdomen of pregnant women. However, separating the weak fetal ECG signal from the abdominal ECG signal is a challenging problem. In this paper, we propose a method for estimating the FHR using sequential total variation denoising and compare its performance with that of other single-channel fetal ECG extraction methods via simulation using the Fetal ECG Synthetic Database (FECGSYNDB). Moreover, we used real data from PhysioNet fetal ECG databases for the evaluation of the algorithm performance. The R-peak detection rate is calculated to evaluate the performance of our algorithm. Our approach could not only separate the fetal ECG signals from the abdominal ECG signals but also accurately estimate the FHR. PMID:27376296

  8. Automatic QRS complex detection algorithm designed for a novel wearable, wireless electrocardiogram recording device

    DEFF Research Database (Denmark)

    Saadi, Dorthe Bodholt; Egstrup, Kenneth; Branebjerg, Jens

    2012-01-01

    We have designed and optimized an automatic QRS complex detection algorithm for electrocardiogram (ECG) signals recorded with the DELTA ePatch platform. The algorithm is able to automatically switch between single-channel and multi-channel analysis mode. This preliminary study includes data from 11...

  9. Availability of a baseline Electrocardiogram changes the application of the Sclarovsky-Birnbaum Myocardial Ischemia Grade

    DEFF Research Database (Denmark)

    Carlsen, Esben A; Bang, Lia E; Køber, Lars

    2014-01-01

    BACKGROUND AND AIMS: The electrocardiogram (ECG) based Sclarovsky-Birnbaum Ischemia Grade may be used to determine the prognosis of patients with ST-elevation myocardial infarction (STEMI). However, application of the method is based on assumption of the baseline QRS morphology. Thus, the aims of...

  10. Normal Limits of Electrocardiogram and Cut-Off Values for Left ...

    African Journals Online (AJOL)

    Gender difference exists in some cut-off values for LVH. This study defined the normal limits for electrocardiographic variables for young adult Nigerians. Racial factor should be taken into consideration in interpretation of ECG. Keywords: Normal limits, Electrocardiogram, Cut-off values, Left ventricular hypertrophy, Young ...

  11. Normal Limits of Electrocardiogram and Cut-Off Values for Left ...

    African Journals Online (AJOL)

    olayemitoyin

    Summary: This study assessed healthy young adults to determine the normal limits for electrocardiographic variables and cut-off values for left ventricular hypertrophy. It was a cross sectional descriptive study in which the participants were evaluated clinically by standard 12-lead resting electrocardiogram (ECG) at 25mm/s ...

  12. Electrocardiograms digitally processed for the investigation of new measures of cardiac diagnosis

    International Nuclear Information System (INIS)

    Gutierrez, Rafael M; Cerquera, Alexander

    2003-01-01

    The ECG F D 1 database that comprises electrocardiograms processed with digital filters is presented. The aim of this work is to build databases in order to perform high sensibility studies of new methods for electrocardiographic analysis based on statistical physics, actually on research. The changes in the original electrocardiograms generated by the digital filters used to build the ECG F D 1 database cannot be detected visually. The effect of these filters on the information, which escapes visual analysis, is actually object of study in order to develop its potential in the support of cardiac diagnosis using the electrocardiogram as the only source of information. The ECG F D 1 database may be very useful in the investigation directed to construct new diagnostic tools in cardiology, using simpler and less expensive electrocardiograms, obtained in more diverse conditions. the study of cardiac dynamics as a complex system starting from a source of information as simple as an electrocardiogram offers possibilities of creating new services that may improve the quality of human life and life expectancy at low costs and possibility of great coverage. One of the purposes of this publication is to draw the scientific community's attention to these investigative problems and its interdisciplinary applications

  13. Referral of patients with ST-segment elevation acute myocardial infarction directly to the catheterization suite based on prehospital teletransmission of 12-lead electrocardiogram

    DEFF Research Database (Denmark)

    Sillesen, Martin; Sejersten, Maria; Strange, Søren

    2008-01-01

    BACKGROUND: Time from symptom onset to reperfusion is essential in patients with ST-segment elevation acute myocardial infarction. Prior studies have indicated that prehospital 12-lead electrocardiogram (ECG) transmission can reduce time to reperfusion. PURPOSE: Determine 12-lead ECG transmission...

  14. ECG biometric identification: A compression based approach.

    Science.gov (United States)

    Bras, Susana; Pinho, Armando J

    2015-08-01

    Using the electrocardiogram signal (ECG) to identify and/or authenticate persons are problems still lacking satisfactory solutions. Yet, ECG possesses characteristics that are unique or difficult to get from other signals used in biometrics: (1) it requires contact and liveliness for acquisition (2) it changes under stress, rendering it potentially useless if acquired under threatening. Our main objective is to present an innovative and robust solution to the above-mentioned problem. To successfully conduct this goal, we rely on information-theoretic data models for data compression and on similarity metrics related to the approximation of the Kolmogorov complexity. The proposed measure allows the comparison of two (or more) ECG segments, without having to follow traditional approaches that require heartbeat segmentation (described as highly influenced by external or internal interferences). As a first approach, the method was able to cluster the data in three groups: identical record, same participant, different participant, by the stratification of the proposed measure with values near 0 for the same participant and closer to 1 for different participants. A leave-one-out strategy was implemented in order to identify the participant in the database based on his/her ECG. A 1NN classifier was implemented, using as distance measure the method proposed in this work. The classifier was able to identify correctly almost all participants, with an accuracy of 99% in the database used.

  15. Robust and Accurate Anomaly Detection in ECG Artifacts Using Time Series Motif Discovery

    Science.gov (United States)

    Sivaraks, Haemwaan

    2015-01-01

    Electrocardiogram (ECG) anomaly detection is an important technique for detecting dissimilar heartbeats which helps identify abnormal ECGs before the diagnosis process. Currently available ECG anomaly detection methods, ranging from academic research to commercial ECG machines, still suffer from a high false alarm rate because these methods are not able to differentiate ECG artifacts from real ECG signal, especially, in ECG artifacts that are similar to ECG signals in terms of shape and/or frequency. The problem leads to high vigilance for physicians and misinterpretation risk for nonspecialists. Therefore, this work proposes a novel anomaly detection technique that is highly robust and accurate in the presence of ECG artifacts which can effectively reduce the false alarm rate. Expert knowledge from cardiologists and motif discovery technique is utilized in our design. In addition, every step of the algorithm conforms to the interpretation of cardiologists. Our method can be utilized to both single-lead ECGs and multilead ECGs. Our experiment results on real ECG datasets are interpreted and evaluated by cardiologists. Our proposed algorithm can mostly achieve 100% of accuracy on detection (AoD), sensitivity, specificity, and positive predictive value with 0% false alarm rate. The results demonstrate that our proposed method is highly accurate and robust to artifacts, compared with competitive anomaly detection methods. PMID:25688284

  16. Real-time fetal ECG extraction from multichannel abdominal ECG using compressive sensing and ICA.

    Science.gov (United States)

    Gurve, Dharmendra; Pant, Jeevan K; Krishnan, Sridhar

    2017-07-01

    An improved method for separation of fetal electrocardiogram (fECG) from abdominal electrocardiogram (abdECG) is proposed in this paper. Proposed method combines two widely used techniques i.e. compressive sensing (CS) and independent component analysis (ICA). Separation of fECG is carried out by applying ICA directly on the compressed signal. The efficient improved ℓ p -regularized least-sqaures (ℓ p -RLS) algorithm is used for signal reconstruction, which provides better reconstruction quality and less processing time in comparison with other existing methods. The proposed algorithm is evaluated and tested on Physionet datasets which contain 75 records in set-A, 100 records in set-B and 6 records in Silesia dataset. The obtained outcomes reveal that proposed algorithm shows promising results (Sensitivity S=92%, Positive predictivity P+ = 93%, F1 measure = 92.5% with average percentage root-mean-square difference PRD =6.89% and Execution time= 2.91 sec.). The results also indicate that there is a substantial improvement in quality of reconstructed signal which is achieved by maintaining lowest PRD.

  17. Amplifier input impedance in dry electrode ECG recording.

    Science.gov (United States)

    Assambo, Cedric; Burke, Martin J

    2009-01-01

    This paper presents a novel approach for designing the front-end of instrumentation amplifiers for use in dry electrode recording of the human electrocardiogram (ECG). The method relies on information provided by the characterization of the skin-electrode interface and the analysis of low frequency ECG criteria defined by international standards. Marginal measurements of capacitive elements of the skin-electrode interface as small as 0.01 microF, suggest values of input impedance in the order of 1.3 GOmega. However, results in 99% of the data analyzed indicate that a recording amplifier providing an input impedance of 500 MOmega should ensure clear signal sensing without distortion.

  18. Learning electrocardiogram on YouTube: how useful is it?

    Science.gov (United States)

    Akgun, Taylan; Karabay, Can Yucel; Kocabay, Gonenc; Kalayci, Arzu; Oduncu, Vecih; Guler, Ahmet; Pala, Selcuk; Kirma, Cevat

    2014-01-01

    YouTube has become a useful resource for knowledge and is widely used by medical students as an e-learning source. The purpose of this study was to assess the videos relating electrocardiogram (ECG) on YouTube. YouTube was searched on May 28, 2013 for the search terms "AF ecg" for atrial fibrillation, "AVNRT" for atrioventricular nodal reentrant tachycardia, "AVRT" for atrioventricular reentrant tachycardia, "AV block or heart block" for atrioventricular block, "LBBB, RBBB" for bundle branch block, "left anterior fascicular block or left posterior fascicular block" for fascicular blocks, "VT ecg" for ventricular tachycardia, "long QT" and "Brugada ecg". Non-English language, unrelated and non-educational videos were excluded. Remaining videos were assessed for usefulness, source and characteristics. Usefulness was assessed with using a checklist developed by the authors. One hundred nineteen videos were included in the analysis. Sources of the videos were as follows: individuals n=70, 58.8%, universities/hospitals n=10, 8.4% and medical organizations n=3, 2.5%, health ads n=10 8.4%, health websites n=26, 21.8%. Fifty-six (47.1%) videos were classified as very useful and 16 (13.4%) videos were misleading. 90% of the videos uploaded by universities/hospitals were grouped as very useful videos, the same ratio was 45% for the individual uploads. There were statistically significant differences in ECG diagnosis among the groups (for very useful, useful and misleading, pYouTube has a substantial amount of videos on ECG with a wide diversity from useful to misleading content. The lack of quality content relating to ECG on YouTube necessitates that videos should be selected with utmost care. © 2013 Elsevier Inc. All rights reserved.

  19. Electrocardiogram interpretation and arrhythmia management: a primary and secondary care survey.

    Science.gov (United States)

    Begg, Gordon; Willan, Kathryn; Tyndall, Keith; Pepper, Chris; Tayebjee, Muzahir

    2016-05-01

    There is increasing desire among service commissioners to treat arrhythmia in primary care. Accurate interpretation of the electrocardiogram (ECG) is fundamental to this. ECG interpretation has previously been shown to vary widely but there is little recent data. To examine the interpretation of ECGs in primary and secondary care. A cross-sectional survey of participants' interpretation of six ECGs and hypothetical management of patients based on those ECGs, at primary care educational events, and a cardiology department in Leeds. A total of 262 primary care clinicians and 20 cardiology clinicians were surveyed via questionnaire. Answers were compared with expert electrophysiologist opinion. In primary care, abnormal ECGs were interpreted as normal by 23% of responders. ST elevation and prolonged QT were incorrectly interpreted as normal by 1% and 22%, respectively. In cardiology, abnormal ECGs were interpreted as normal by 3%. ECG provision and interpretation remains inconsistent in both primary and secondary care. Primary care practitioners are less experienced and less confident with ECG interpretation than cardiologists, and require support in this area. © British Journal of General Practice 2016.

  20. Correlation of Respiratory Signals and Electrocardiogram Signals via Empirical Mode Decomposition

    KAUST Repository

    El Fiky, Ahmed Osama

    2011-05-24

    Recently Electrocardiogram (ECG) signals are being broadly used as an essential diagnosing tool in different clinical applications as they carry a reliable representation not only for cardiac activities, but also for other associated biological processes, like respiration. However, the process of recording and collecting them has usually suffered from the presence of some undesired noises, which in turn affects the reliability of such representations.Therefore, de-noising ECG signals became a hot research field for signal processing experts to ensure better and clear representation of the different cardiac activities. Given the nonlinear and non-stationary properties of ECGs, it is not a simple task to cancel the undesired noise terms without affecting the biological physics of them. In this study, we are interested in correlating the ECG signals with respiratory parameters, specifically the lung volume and lung pressure. We have focused on the concept of de-noising ECG signals by means of signal decomposition using an algorithm called the Empirical Mode Decomposition (EMD) where the original ECG signals are being decomposed into a set of intrinsic mode functions (IMF). Then, we have provided criteria based on which some of these IMFs have been adapted to reconstruct de-noised ECG version. Finally, we have utilized de-noised ECGs as well as IMFs for to study the correlation with lung volume and lung pressure. These correlation studies have showed some clear resemblance especially between the oscillations of ECGs and lung pressures.

  1. Biomedical implementation of liquid metal ink as drawable ECG electrode and skin circuit.

    Science.gov (United States)

    Yu, Yang; Zhang, Jie; Liu, Jing

    2013-01-01

    Conventional ways of making bio-electrodes are generally complicated, expensive and unconformable. Here we describe for the first time the method of applying Ga-based liquid metal ink as drawable electrocardiogram (ECG) electrodes. Such material owns unique merits in both liquid phase conformability and high electrical conductivity, which provides flexible ways for making electrical circuits on skin surface and a prospective substitution of conventional rigid printed circuit boards (PCBs). Fundamental measurements of impedance and polarization voltage of the liquid metal ink were carried out to evaluate its basic electrical properties. Conceptual experiments were performed to draw the alloy as bio-electrodes to acquire ECG signals from both rabbit and human via a wireless module developed on the mobile phone. Further, a typical electrical circuit was drawn in the palm with the ink to demonstrate its potential of implementing more sophisticated skin circuits. With an oxide concentration of 0.34%, the resistivity of the liquid metal ink was measured as 44.1 µΩ·cm with quite low reactance in the form of straight line. Its peak polarization voltage with the physiological saline was detected as -0.73 V. The quality of ECG wave detected from the liquid metal electrodes was found as good as that of conventional electrodes, from both rabbit and human experiments. In addition, the circuit drawn with the liquid metal ink in the palm also runs efficiently. When the loop was switched on, all the light emitting diodes (LEDs) were lit and emitted colorful lights. The liquid metal ink promises unique printable electrical properties as both bio-electrodes and electrical wires. The implemented ECG measurement on biological surface and the successfully run skin circuit demonstrated the conformability and attachment of the liquid metal. The present method is expected to innovate future physiological measurement and biological circuit manufacturing technique in a large extent.

  2. Biomedical implementation of liquid metal ink as drawable ECG electrode and skin circuit.

    Directory of Open Access Journals (Sweden)

    Yang Yu

    Full Text Available BACKGROUND: Conventional ways of making bio-electrodes are generally complicated, expensive and unconformable. Here we describe for the first time the method of applying Ga-based liquid metal ink as drawable electrocardiogram (ECG electrodes. Such material owns unique merits in both liquid phase conformability and high electrical conductivity, which provides flexible ways for making electrical circuits on skin surface and a prospective substitution of conventional rigid printed circuit boards (PCBs. METHODS: Fundamental measurements of impedance and polarization voltage of the liquid metal ink were carried out to evaluate its basic electrical properties. Conceptual experiments were performed to draw the alloy as bio-electrodes to acquire ECG signals from both rabbit and human via a wireless module developed on the mobile phone. Further, a typical electrical circuit was drawn in the palm with the ink to demonstrate its potential of implementing more sophisticated skin circuits. RESULTS: With an oxide concentration of 0.34%, the resistivity of the liquid metal ink was measured as 44.1 µΩ·cm with quite low reactance in the form of straight line. Its peak polarization voltage with the physiological saline was detected as -0.73 V. The quality of ECG wave detected from the liquid metal electrodes was found as good as that of conventional electrodes, from both rabbit and human experiments. In addition, the circuit drawn with the liquid metal ink in the palm also runs efficiently. When the loop was switched on, all the light emitting diodes (LEDs were lit and emitted colorful lights. CONCLUSIONS: The liquid metal ink promises unique printable electrical properties as both bio-electrodes and electrical wires. The implemented ECG measurement on biological surface and the successfully run skin circuit demonstrated the conformability and attachment of the liquid metal. The present method is expected to innovate future physiological measurement and

  3. ECG abnormalities in patients with chronic kidney disease

    International Nuclear Information System (INIS)

    Shafi, S.; Saleem, M.; Anjum, R.; Abdullah, W.; Shafi, T.

    2017-01-01

    Chronic kidney disease (CKD) is associated with increased risk of cardiovascular disease. Electrocardiographic (ECG) abnormalities are common in CKD patients. However, there is variation in literature regarding frequency of ECG abnormalities in CKD patients and limited information in local population. Methods: The study design was cross-sectional in nature. All patients between ages of 20-80 years with CKD not previously on renal replacement therapy who were admitted to nephrology ward at a tertiary care facility over a 6-month period were included. All patients underwent 12 lead electrocardiograms (ECG). ECG abnormalities were defined based on accepted standard criteria. Results: Total number of patients included in the study was 124. Mean age of all patients was 49.9+-13.8 years, 106 (84.8%) had hypertension, 84 (70%) had diabetes mellitus, and 35 (29.9%) had known cardiovascular disease. Mean serum creatinine was 7.2+-3.4 mg/dl, mean eGFR was 10.6+-9.2 ml/min/1.73 m/sup 2/. Overall 78.4% of all CKD patients have one or more ECG abnormality. Left ventricular hypertrophy (40%), Q waves (27.2%), ST segment elevation or depression (23.4%), prolonged QRS duration (19.2%), tachycardia (17.6%) and left and right atrial enlargement (17.6%) were the most common abnormalities. Conclusion: ECG abnormalities are common in hospitalized CKD patients in local population. All hospitalized CKD patients should undergo ECG to screen for cardiovascular disease. (author)

  4. Diagnostic Role of ECG Recording Simultaneously With EEG Testing.

    Science.gov (United States)

    Kendirli, Mustafa Tansel; Aparci, Mustafa; Kendirli, Nurten; Tekeli, Hakan; Karaoglan, Mustafa; Senol, Mehmet Guney; Togrol, Erdem

    2015-07-01

    Arrhythmia is not uncommon in the etiology of syncope which mimics epilepsy. Data about the epilepsy induced vagal tonus abnormalities have being increasingly reported. So we aimed to evaluate what a neurologist may gain by a simultaneous electrocardiogram (ECG) and electroencephalogram (EEG) recording in the patients who underwent EEG testing due to prediagnosis of epilepsy. We retrospectively evaluated and detected ECG abnormalities in 68 (18%) of 376 patients who underwent EEG testing. A minimum of 20 of minutes artifact-free recording were required for each patient. Standard 1-channel ECG was simultaneously recorded in conjunction with the EEG. In all, 28% of females and 14% of males had ECG abnormalities. Females (mean age 49 years, range 18-88 years) were older compared with the male group (mean age 28 years, range 16-83 years). Atrial fibrillation was more frequent in female group whereas bradycardia and respiratory sinus arrhythmia was higher in male group. One case had been detected a critical asystole indicating sick sinus syndrome in the female group and treated with a pacemaker implantation in the following period. Simultaneous ECG recording in conjunction with EEG testing is a clinical prerequisite to detect and to clarify the coexisting ECG and EEG abnormalities and their clinical relevance. Potentially rare lethal causes of syncope that mimic seizure or those that could cause resistance to antiepileptic therapy could effectively be distinguished by detecting ECG abnormalities coinciding with the signs and abnormalities during EEG recording. © EEG and Clinical Neuroscience Society (ECNS) 2014.

  5. A micropower electrocardiogram amplifier.

    Science.gov (United States)

    Fay, L; Misra, V; Sarpeshkar, R

    2009-10-01

    We introduce an electrocardiogram (EKG) preamplifier with a power consumption of 2.8 muW, 8.1 muVrms input-referred noise, and a common-mode rejection ratio of 90 dB. Compared to previously reported work, this amplifier represents a significant reduction in power with little compromise in signal quality. The improvement in performance may be attributed to many optimizations throughout the design including the use of subthreshold transistor operation to improve noise efficiency, gain-setting capacitors versus resistors, half-rail operation wherever possible, optimal power allocations among amplifier blocks, and the sizing of devices to improve matching and reduce noise. We envision that the micropower amplifier can be used as part of a wireless EKG monitoring system powered by rectified radio-frequency energy or other forms of energy harvesting like body vibration and body heat.

  6. Design of a smart ECG garment based on conductive textile electrode and flexible printed circuit board.

    Science.gov (United States)

    Cai, Zhipeng; Luo, Kan; Liu, Chengyu; Li, Jianqing

    2017-08-09

    A smart electrocardiogram (ECG) garment system was designed for continuous, non-invasive and comfortable ECG monitoring, which mainly consists of four components: Conductive textile electrode, garment, flexible printed circuit board (FPCB)-based ECG processing module and android application program. Conductive textile electrode and FPCB-based ECG processing module (6.8 g, 55 mm × 53 mm × 5 mm) are identified as two key techniques to improve the system's comfort and flexibility. Preliminary experimental results verified that the textile electrodes with circle shape, 40 mm size in diameter, and 5 mm thickness sponge are best suited for the long-term ECG monitoring application. The tests on the whole system confirmed that the designed smart garment can obtain long-term ECG recordings with high signal quality.

  7. A new feature detection mechanism and its application in secured ECG transmission with noise masking.

    Science.gov (United States)

    Sufi, Fahim; Khalil, Ibrahim

    2009-04-01

    With cardiovascular disease as the number one killer of modern era, Electrocardiogram (ECG) is collected, stored and transmitted in greater frequency than ever before. However, in reality, ECG is rarely transmitted and stored in a secured manner. Recent research shows that eavesdropper can reveal the identity and cardiovascular condition from an intercepted ECG. Therefore, ECG data must be anonymized before transmission over the network and also stored as such in medical repositories. To achieve this, first of all, this paper presents a new ECG feature detection mechanism, which was compared against existing cross correlation (CC) based template matching algorithms. Two types of CC methods were used for comparison. Compared to the CC based approaches, which had 40% and 53% misclassification rates, the proposed detection algorithm did not perform any single misclassification. Secondly, a new ECG obfuscation method was designed and implemented on 15 subjects using added noises corresponding to each of the ECG features. This obfuscated ECG can be freely distributed over the internet without the necessity of encryption, since the original features needed to identify personal information of the patient remain concealed. Only authorized personnel possessing a secret key will be able to reconstruct the original ECG from the obfuscated ECG. Distribution of the would appear as regular ECG without encryption. Therefore, traditional decryption techniques including powerful brute force attack are useless against this obfuscation.

  8. Digitization of Electrocardiogram From Telemetry Prior to In-hospital Cardiac Arrest: A Pilot Study.

    Science.gov (United States)

    Attin, Mina; Wang, Lu; Soroushmehr, S M Reza; Lin, Chii-Dean; Lemus, Hector; Spadafore, Maxwell; Najarian, Kayvan

    2016-03-01

    Analyzing telemetry electrocardiogram (ECG) data over an extended period is often time-consuming because digital records are not widely available at hospitals. Investigating trends and patterns in the ECG data could lead to establishing predictors that would shorten response time to in-hospital cardiac arrest (I-HCA). This study was conducted to validate a novel method of digitizing paper ECG tracings from telemetry systems in order to facilitate the use of heart rate as a diagnostic feature prior to I-HCA. This multicenter study used telemetry to investigate full-disclosure ECG papers of 44 cardiovascular patients obtained within 1 hr of I-HCA with initial rhythms of pulseless electrical activity and asystole. Digital ECGs were available for seven of these patients. An algorithm to digitize the full-disclosure ECG papers was developed using the shortest path method. The heart rate was measured manually (averaging R-R intervals) for ECG papers and automatically for digitized and digital ECGs. Significant correlations were found between manual and automated measurements of digitized ECGs (p < .001) and between digitized and digital ECGs (p < .001). Bland-Altman methods showed bias = .001 s, SD = .0276 s, lower and upper 95% limits of agreement for digitized and digital ECGs = .055 and -.053 s, and percentage error = 0.22%. Root mean square (rms), percentage rms difference, and signal to noise ratio values were in acceptable ranges. The digitization method was validated. Digitized ECG provides an efficient and accurate way of measuring heart rate over an extended period of time. © The Author(s) 2015.

  9. Normal limits of the electrocardiogram derived from a large database of Brazilian primary care patients.

    Science.gov (United States)

    Palhares, Daniel M F; Marcolino, Milena S; Santos, Thales M M; da Silva, José L P; Gomes, Paulo R; Ribeiro, Leonardo B; Macfarlane, Peter W; Ribeiro, Antonio L P

    2017-06-13

    Knowledge of the normal limits of the electrocardiogram (ECG) is mandatory for establishing which patients have abnormal ECGs. No studies have assessed the reference standards for a Latin American population. Our aim was to establish the normal ranges of the ECG for pediatric and adult Brazilian primary care patients. This retrospective observational study assessed all the consecutive 12-lead digital electrocardiograms of primary care patients at least 1 year old in Minas Gerais state, Brazil, recorded between 2010 and 2015. ECGs were excluded if there were technical problems, selected abnormalities were present or patients with selected self-declared comorbidities or on drug therapy. Only the first ECG from patients with multiple ECGs was accepted. The University of Glasgow ECG analysis program was used to automatically interpret the ECGs. For each variable, the 1st, 2nd, 50th, 98th and 99th percentiles were determined and results were compared to selected studies. A total of 1,493,905 ECGs were recorded. 1,007,891 were excluded and 486.014 were analyzed. This large study provided normal values for heart rate, P, QRS and T frontal axis, P and QRS overall duration, PR and QT overall intervals and QTc corrected by Hodges, Bazett, Fridericia and Framingham formulae. Overall, the results were similar to those from other studies performed in different populations but there were differences in extreme ages and specific measurements. This study has provided reference values for Latinos of both sexes older than 1 year. Our results are comparable to studies performed in different populations.

  10. Comparison of Digital 12-Lead ECG and Digital 12-Lead Holter ECG Recordings in Healthy Male Subjects: Results from a Randomized, Double-Blinded, Placebo-Controlled Clinical Trial.

    Science.gov (United States)

    Wang, Duolao; Bakhai, Ameet; Arezina, Radivoj; Täubel, Jörg

    2016-11-01

    Electrocardiogram (ECG) variability is greatly affected by the ECG recording method. This study aims to compare Holter and standard ECG recording methods in terms of central locations and variations of ECG data. We used the ECG data from a double-blinded, placebo-controlled, randomized clinical trial and used a mixed model approach to assess the agreement between two methods in central locations and variations of eight ECG parameters (Heart Rate, PR, QRS, QT, RR, QTcB, QTcF, and QTcI intervals). A total of 34 heathy male subjects with mean age of 25.7 ± 4.78 years were randomized to receive either active drug or placebo. Digital 12-lead ECG and digital 12-lead Holter ECG recordings were performed to assess ECG variability. There are no significant differences in least square mean between the Holter and the standard method for all ECG parameters. The total variance is consistently higher for the Holter method than the standard method for all ECG parameters except for QRS. The intraclass correlation coefficient (ICC) values for the Holter method are consistently lower than those for the standard method for all ECG parameters except for QRS, in particular, the ICC for QTcF is reduced from 0.86 for the standard method to 0.67 for the Holter method. This study suggests that Holter ECGs recorded in a controlled environment are not significantly different but more variable than those from the standard method. © 2016 Wiley Periodicals, Inc.

  11. Development of new anatomy reconstruction software to localize cardiac isochrones to the cardiac surface from the 12 lead ECG.

    Science.gov (United States)

    van Dam, Peter M; Gordon, Jeffrey P; Laks, Michael M; Boyle, Noel G

    2015-01-01

    medical image data (pixel size software tool has been introduced, which is able to reconstruct accurate cardiac anatomical models from MRI or CT within only a few hours. This new anatomical reconstruction tool might reduce the modeling errors within the cardiac isochrone positioning system and thus enable the clinical application of CIPS to localize the PVC/VT focus to the ventricular myocardium from only the standard 12 lead ECG. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Specific circuit design: electrocardiogram amplifier

    International Nuclear Information System (INIS)

    Laribiere, Laurent

    1991-01-01

    The electrocardiogram amplifier is a specific integrated circuit. It is based on a linear array of Raytheon. This circuit is fitted with the following functions and characteristics: - electrocardiogram signals amplification, - pacemaker detection, - electrode un-sticking detection, - defibrillator overload protection, - battery-powered, - internal regulation 5 V, - low supply current 2.5 mA, - according to French norms on electrocardiogram surveillance devices - 28 pin package, available in CMS version It can be used for any surveillance device, requiring an analog processing of cardiac signals. (author) [fr

  13. Value of the 12-lead electrocardiogram to define the level of obstruction in acute anterior wall myocardial infarction: correlation to coronary angiography and clinical outcome in the DANAMI-2 trial

    DEFF Research Database (Denmark)

    Eskola, Markku J; Nikus, Kjell C; Holmvang, Lene

    2008-01-01

    BACKGROUND: Acute anterior myocardial infarction (MI) caused by proximal occlusion of the left anterior descending coronary artery (LAD), is associated with unfavourable outcome and should be recognized by simple noninvasive methods like the 12-lead electrocardiogram (ECG). METHODS: In a prospect......BACKGROUND: Acute anterior myocardial infarction (MI) caused by proximal occlusion of the left anterior descending coronary artery (LAD), is associated with unfavourable outcome and should be recognized by simple noninvasive methods like the 12-lead electrocardiogram (ECG). METHODS...

  14. The differences in electrocardiogram interpretation in top-level athletes.

    Science.gov (United States)

    Jakubiak, Agnieszka A; Burkhard-Jagodzińska, Krystyna; Król, Wojciech; Konopka, Marcin; Bursa, Dominik; Sitkowski, Dariusz; Kuch, Marek; Braksator, Wojciech

    2017-01-01

    The Ministry of Health in Poland recommends electrocardiogram (ECG)-based cardiovascular screening in athletes, but so far there has been a lack of guidelines on preparticipation assessment. We compared different criteria of ECG screening assessment in a group of top-level athletes. The aims were to evaluate the prevalence of ECG changes in athletes that necessitate further cardiological work-up according to three criteria in various age groups as well as to identify factors determining the occurrence of changes related and unrelated to the training. 262 high-dynamic, high-static Polish athletes (rowers, cyclists, canoeists) were divided into two age categories: young (≤ 18 years of age; n = 177, mean age 16.9 ± 0.8; 15-18 years) and elite (> 18 years of age; n = 85, mean age 22.9 ± 3.4; 19-34 years). All sports persons had a 12-lead ECG performed and evaluated according to 2010 European Society of Cardiology (ESC) recommendations, 2012 Seattle criteria, and 2014 Refined criteria. The Refined criteria reduced (p < 0.001) the number of training-unrelated ECG findings to 8.0% vs. 12.6% (Seattle criteria) and 30.5% (ESC recommendations). All three criteria revealed more training-related changes in the group of older athletes (76.5% vs. 55.9%, p = 0.001). Predictors that significantly (p < 0.005) affected the occurrence of adaptive changes were the age of the athlete, training duration (in years), and male gender. 1. The ESC criteria identified a group of athletes that was unacceptably large, as for the screening test, requiring verification with other methods (every fourth athlete). 2. The use of the Refined criteria helps to significantly reduce the frequency and necessity for additional tests. 3. The dependence of adaptive changes on training duration and athletes' age confirms the benign nature of those ECG findings.

  15. Quality Aware Compression of Electrocardiogram Using Principal Component Analysis.

    Science.gov (United States)

    Gupta, Rajarshi

    2016-05-01

    Electrocardiogram (ECG) compression finds wide application in various patient monitoring purposes. Quality control in ECG compression ensures reconstruction quality and its clinical acceptance for diagnostic decision making. In this paper, a quality aware compression method of single lead ECG is described using principal component analysis (PCA). After pre-processing, beat extraction and PCA decomposition, two independent quality criteria, namely, bit rate control (BRC) or error control (EC) criteria were set to select optimal principal components, eigenvectors and their quantization level to achieve desired bit rate or error measure. The selected principal components and eigenvectors were finally compressed using a modified delta and Huffman encoder. The algorithms were validated with 32 sets of MIT Arrhythmia data and 60 normal and 30 sets of diagnostic ECG data from PTB Diagnostic ECG data ptbdb, all at 1 kHz sampling. For BRC with a CR threshold of 40, an average Compression Ratio (CR), percentage root mean squared difference normalized (PRDN) and maximum absolute error (MAE) of 50.74, 16.22 and 0.243 mV respectively were obtained. For EC with an upper limit of 5 % PRDN and 0.1 mV MAE, the average CR, PRDN and MAE of 9.48, 4.13 and 0.049 mV respectively were obtained. For mitdb data 117, the reconstruction quality could be preserved up to CR of 68.96 by extending the BRC threshold. The proposed method yields better results than recently published works on quality controlled ECG compression.

  16. Electrocardiogram signal denoising based on empirical mode decomposition technique: an overview

    Science.gov (United States)

    Han, G.; Lin, B.; Xu, Z.

    2017-03-01

    Electrocardiogram (ECG) signal is nonlinear and non-stationary weak signal which reflects whether the heart is functioning normally or abnormally. ECG signal is susceptible to various kinds of noises such as high/low frequency noises, powerline interference and baseline wander. Hence, the removal of noises from ECG signal becomes a vital link in the ECG signal processing and plays a significant role in the detection and diagnosis of heart diseases. The review will describe the recent developments of ECG signal denoising based on Empirical Mode Decomposition (EMD) technique including high frequency noise removal, powerline interference separation, baseline wander correction, the combining of EMD and Other Methods, EEMD technique. EMD technique is a quite potential and prospective but not perfect method in the application of processing nonlinear and non-stationary signal like ECG signal. The EMD combined with other algorithms is a good solution to improve the performance of noise cancellation. The pros and cons of EMD technique in ECG signal denoising are discussed in detail. Finally, the future work and challenges in ECG signal denoising based on EMD technique are clarified.

  17. Development and significance of a fetal electrocardiogram recorded by signal-averaged high-amplification electrocardiography.

    Science.gov (United States)

    Hayashi, Risa; Nakai, Kenji; Fukushima, Akimune; Itoh, Manabu; Sugiyama, Toru

    2009-03-01

    Although ultrasonic diagnostic imaging and fetal heart monitors have undergone great technological improvements, the development and use of fetal electrocardiograms to evaluate fetal arrhythmias and autonomic nervous activity have not been fully established. We verified the clinical significance of the novel signal-averaged vector-projected high amplification ECG (SAVP-ECG) method in fetuses from 48 gravidas at 32-41 weeks of gestation and in 34 neonates. SAVP-ECGs from fetuses and newborns were recorded using a modified XYZ-leads system. Once noise and maternal QRS waves were removed, the P, QRS, and T wave intervals were measured from the signal-averaged fetal ECGs. We also compared fetal and neonatal heart rates (HRs), coefficients of variation of heart rate variability (CV) as a parasympathetic nervous activity, and the ratio of low to high frequency (LF/HF ratio) as a sympathetic nervous activity. The rate of detection of a fetal ECG by SAVP-ECG was 72.9%, and the fetal and neonatal QRS and QTc intervals were not significantly different. The neonatal CVs and LF/HF ratios were significantly increased compared with those in the fetus. In conclusion, we have developed a fetal ECG recording method using the SAVP-ECG system, which we used to evaluate autonomic nervous system development.

  18. Extraction of fetal electrocardiogram using adaptive neuro-fuzzy inference systems.

    Science.gov (United States)

    Assaleh, Khaled

    2007-01-01

    In this paper, we investigate the use of adaptive neuro-fuzzy inference systems (ANFIS) for fetal electrocardiogram (FECG) extraction from two ECG signals recorded at the thoracic and abdominal areas of the mother's skin. The thoracic ECG is assumed to be almost completely maternal (MECG) while the abdominal ECG is considered to be composite as it contains both the mother's and the fetus' ECG signals. The maternal component in the abdominal ECG signal is a nonlinearly transformed version of the MECG. We use an ANFIS network to identify this nonlinear relationship, and to align the MECG signal with the maternal component in the abdominal ECG signal. Thus, we extract the FECG component by subtracting the aligned version of the MECG signal from the abdominal ECG signal. We validate our technique on both real and synthetic ECG signals. Our results demonstrate the effectiveness of the proposed technique in extracting the FECG component from abdominal signals of very low maternal to fetal signal-to-noise ratios. The results also show that the technique is capable of extracting the FECG even when it is totally embedded within the maternal QRS complex.

  19. A Fixed-Lag Kalman Smoother to Filter Power Line Interference in Electrocardiogram Recordings.

    Science.gov (United States)

    Warmerdam, G J J; Vullings, R; Schmitt, L; Van Laar, J O E H; Bergmans, J W M

    2017-08-01

    Filtering power line interference (PLI) from electrocardiogram (ECG) recordings can lead to significant distortions of the ECG and mask clinically relevant features in ECG waveform morphology. The objective of this study is to filter PLI from ECG recordings with minimal distortion of the ECG waveform. In this paper, we propose a fixed-lag Kalman smoother with adaptive noise estimation. The performance of this Kalman smoother in filtering PLI is compared to that of a fixed-bandwidth notch filter and several adaptive PLI filters that have been proposed in the literature. To evaluate the performance, we corrupted clean neonatal ECG recordings with various simulated PLI. Furthermore, examples are shown of filtering real PLI from an adult and a fetal ECG recording. The fixed-lag Kalman smoother outperforms other PLI filters in terms of step response settling time (improvements that range from 0.1 to 1 s) and signal-to-noise ratio (improvements that range from 17 to 23 dB). Our fixed-lag Kalman smoother can be used for semi real-time applications with a limited delay of 0.4 s. The fixed-lag Kalman smoother presented in this study outperforms other methods for filtering PLI and leads to minimal distortion of the ECG waveform.

  20. A Precise Drunk Driving Detection Using Weighted Kernel Based on Electrocardiogram

    Directory of Open Access Journals (Sweden)

    Chung Kit Wu

    2016-05-01

    Full Text Available Globally, 1.2 million people die and 50 million people are injured annually due to traffic accidents. These traffic accidents cost $500 billion dollars. Drunk drivers are found in 40% of the traffic crashes. Existing drunk driving detection (DDD systems do not provide accurate detection and pre-warning concurrently. Electrocardiogram (ECG is a proven biosignal that accurately and simultaneously reflects human’s biological status. In this letter, a classifier for DDD based on ECG is investigated in an attempt to reduce traffic accidents caused by drunk drivers. At this point, it appears that there is no known research or literature found on ECG classifier for DDD. To identify drunk syndromes, the ECG signals from drunk drivers are studied and analyzed. As such, a precise ECG-based DDD (ECG-DDD using a weighted kernel is developed. From the measurements, 10 key features of ECG signals were identified. To incorporate the important features, the feature vectors are weighted in the customization of kernel functions. Four commonly adopted kernel functions are studied. Results reveal that weighted feature vectors improve the accuracy by 11% compared to the computation using the prime kernel. Evaluation shows that ECG-DDD improved the accuracy by 8% to 18% compared to prevailing methods.

  1. A Precise Drunk Driving Detection Using Weighted Kernel Based on Electrocardiogram.

    Science.gov (United States)

    Wu, Chung Kit; Tsang, Kim Fung; Chi, Hao Ran; Hung, Faan Hei

    2016-05-09

    Globally, 1.2 million people die and 50 million people are injured annually due to traffic accidents. These traffic accidents cost $500 billion dollars. Drunk drivers are found in 40% of the traffic crashes. Existing drunk driving detection (DDD) systems do not provide accurate detection and pre-warning concurrently. Electrocardiogram (ECG) is a proven biosignal that accurately and simultaneously reflects human's biological status. In this letter, a classifier for DDD based on ECG is investigated in an attempt to reduce traffic accidents caused by drunk drivers. At this point, it appears that there is no known research or literature found on ECG classifier for DDD. To identify drunk syndromes, the ECG signals from drunk drivers are studied and analyzed. As such, a precise ECG-based DDD (ECG-DDD) using a weighted kernel is developed. From the measurements, 10 key features of ECG signals were identified. To incorporate the important features, the feature vectors are weighted in the customization of kernel functions. Four commonly adopted kernel functions are studied. Results reveal that weighted feature vectors improve the accuracy by 11% compared to the computation using the prime kernel. Evaluation shows that ECG-DDD improved the accuracy by 8% to 18% compared to prevailing methods.

  2. Steganography in arrhythmic electrocardiogram signal.

    Science.gov (United States)

    Edward Jero, S; Ramu, Palaniappan; Ramakrishnan, S

    2015-08-01

    Security and privacy of patient data is a vital requirement during exchange/storage of medical information over communication network. Steganography method hides patient data into a cover signal to prevent unauthenticated accesses during data transfer. This study evaluates the performance of ECG steganography to ensure secured transmission of patient data where an abnormal ECG signal is used as cover signal. The novelty of this work is to hide patient data into two dimensional matrix of an abnormal ECG signal using Discrete Wavelet Transform and Singular Value Decomposition based steganography method. A 2D ECG is constructed according to Tompkins QRS detection algorithm. The missed R peaks are computed using RR interval during 2D conversion. The abnormal ECG signals are obtained from the MIT-BIH arrhythmia database. Metrics such as Peak Signal to Noise Ratio, Percentage Residual Difference, Kullback-Leibler distance and Bit Error Rate are used to evaluate the performance of the proposed approach.

  3. Electrocardiogram Scanner-System Requirements

    Science.gov (United States)

    1973-03-01

    An experimental and analytical study has been conducted to establish the feasibility for scanning and digitizing electrocardiogram records. The technical requirements and relative costs for two systems are discussed herein. One is designed to automat...

  4. The PLR-DTW method for ECG based biometric identification.

    Science.gov (United States)

    Shen, Jun; Bao, Shu-Di; Yang, Li-Cai; Li, Ye

    2011-01-01

    There has been a surge of research on electrocardiogram (ECG) signal based biometric for person identification. Though most of the existing studies claimed that ECG signal is unique to an individual and can be a viable biometric, one of the main difficulties for real-world applications of ECG biometric is the accuracy performance. To address this problem, this study proposes a PLR-DTW method for ECG biometric, where the Piecewise Linear Representation (PLR) is used to keep important information of an ECG signal segment while reduce the data dimension at the same time if necessary, and the Dynamic Time Warping (DTW) is used for similarity measures between two signal segments. The performance evaluation was carried out on three ECG databases, and the existing method using wavelet coefficients, which was proved to have good accuracy performance, was selected for comparison. The analysis results show that the PLR-DTW method achieves an accuracy rate of 100% for identification, while the one using wavelet coefficients achieved only around 93%.

  5. Automatic ECG quality scoring methodology: mimicking human annotators.

    Science.gov (United States)

    Johannesen, Lars; Galeotti, Loriano

    2012-09-01

    An algorithm to determine the quality of electrocardiograms (ECGs) can enable inexperienced nurses and paramedics to record ECGs of sufficient diagnostic quality. Previously, we proposed an algorithm for determining if ECG recordings are of acceptable quality, which was entered in the PhysioNet Challenge 2011. In the present work, we propose an improved two-step algorithm, which first rejects ECGs with macroscopic errors (signal absent, large voltage shifts or saturation) and subsequently quantifies the noise (baseline, powerline or muscular noise) on a continuous scale. The performance of the improved algorithm was evaluated using the PhysioNet Challenge database (1500 ECGs rated by humans for signal quality). We achieved a classification accuracy of 92.3% on the training set and 90.0% on the test set. The improved algorithm is capable of detecting ECGs with macroscopic errors and giving the user a score of the overall quality. This allows the user to assess the degree of noise and decide if it is acceptable depending on the purpose of the recording.

  6. ECG fiducial point extraction using switching Kalman filter.

    Science.gov (United States)

    Akhbari, Mahsa; Ghahjaverestan, Nasim Montazeri; Shamsollahi, Mohammad B; Jutten, Christian

    2018-04-01

    In this paper, we propose a novel method for extracting fiducial points (FPs) of the beats in electrocardiogram (ECG) signals using switching Kalman filter (SKF). In this method, according to McSharry's model, ECG waveforms (P-wave, QRS complex and T-wave) are modeled with Gaussian functions and ECG baselines are modeled with first order auto regressive models. In the proposed method, a discrete state variable called "switch" is considered that affects only the observation equations. We denote a mode as a specific observation equation and switch changes between 7 modes and corresponds to different segments of an ECG beat. At each time instant, the probability of each mode is calculated and compared among two consecutive modes and a path is estimated, which shows the relation of each part of the ECG signal to the mode with the maximum probability. ECG FPs are found from the estimated path. For performance evaluation, the Physionet QT database is used and the proposed method is compared with methods based on wavelet transform, partially collapsed Gibbs sampler (PCGS) and extended Kalman filter. For our proposed method, the mean error and the root mean square error across all FPs are 2 ms (i.e. less than one sample) and 14 ms, respectively. These errors are significantly smaller than those obtained using other methods. The proposed method achieves lesser RMSE and smaller variability with respect to others. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Live ECG readings using Google Glass in emergency situations.

    Science.gov (United States)

    Schaer, Roger; Salamin, Fanny; Jimenez Del Toro, Oscar Alfonso; Atzori, Manfredo; Muller, Henning; Widmer, Antoine

    2015-01-01

    Most sudden cardiac problems require rapid treatment to preserve life. In this regard, electrocardiograms (ECG) shown on vital parameter monitoring systems help medical staff to detect problems. In some situations, such monitoring systems may display information in a less than convenient way for medical staff. For example, vital parameters are displayed on large screens outside the field of view of a surgeon during cardiac surgery. This may lead to losing time and to mistakes when problems occur during cardiac operations. In this paper we present a novel approach to display vital parameters such as the second derivative of the ECG rhythm and heart rate close to the field of view of a surgeon using Google Glass. As a preliminary assessment, we run an experimental study to verify the possibility for medical staff to identify abnormal ECG rhythms from Google Glass. This study compares 6 ECG rhythms readings from a 13.3 inch laptop screen and from the prism of Google Glass. Seven medical residents in internal medicine participated in the study. The preliminary results show that there is no difference between identifying these 6 ECG rhythms from the laptop screen versus Google Glass. Both allow close to perfect identification of the 6 common ECG rhythms. This shows the potential of connected glasses such as Google Glass to be useful in selected medical applications.

  8. An automatic gain control circuit to improve ECG acquisition

    Directory of Open Access Journals (Sweden)

    Marco Rovetta

    2017-11-01

    Full Text Available Abstract Introduction Long-term electrocardiogram (ECG recordings are widely employed to assist the diagnosis of cardiac and sleep disorders. However, variability of ECG amplitude during the recordings hampers the detection of QRS complexes by algorithms. This work presents a simple electronic circuit to automatically normalize the ECG amplitude, improving its sampling by analog to digital converters (ADCs. Methods The proposed circuit consists of an analog divider that normalizes the ECG amplitude using its absolute peak value as reference. The reference value is obtained by means of a full-wave rectifier and a peak voltage detector. The circuit and tasks of its different stages are described. Results Example of the circuit performance for a bradycardia ECG signal (40bpm is presented; the signal has its amplitude suddenly halved, and later, restored. The signal is automatically normalized after 5 heart beats for the amplitude drop. For the amplitude increase, the signal is promptly normalized. Conclusion The proposed circuit adjusts the ECG amplitude to the input voltage range of ADC, avoiding signal to noise ratio degradation of the sampled waveform in order to allow a better performance of processing algorithms.

  9. Convolutional Neural Networks for patient-specific ECG classification.

    Science.gov (United States)

    Kiranyaz, Serkan; Ince, Turker; Hamila, Ridha; Gabbouj, Moncef

    2015-01-01

    We propose a fast and accurate patient-specific electrocardiogram (ECG) classification and monitoring system using an adaptive implementation of 1D Convolutional Neural Networks (CNNs) that can fuse feature extraction and classification into a unified learner. In this way, a dedicated CNN will be trained for each patient by using relatively small common and patient-specific training data and thus it can also be used to classify long ECG records such as Holter registers in a fast and accurate manner. Alternatively, such a solution can conveniently be used for real-time ECG monitoring and early alert system on a light-weight wearable device. The experimental results demonstrate that the proposed system achieves a superior classification performance for the detection of ventricular ectopic beats (VEB) and supraventricular ectopic beats (SVEB).

  10. ecg-kit: a Matlab Toolbox for Cardiovascular Signal Processing

    Directory of Open Access Journals (Sweden)

    Andrés Julio Demski

    2016-04-01

    Full Text Available The electrocardiogram kit ('ecg-kit' for Matlab is an application-programming interface (API developed to provide users a common interface to access and process cardiovascular signals. In the current version, the toolbox supports several ECG recording formats, most of them used by the most popular databases, which allows access to more than 7 TB of information, stored in public databases such as those included in Physionet or the THEW project. The toolbox includes several algorithms frequently used in cardiovascular signal processing, such as heartbeat detectors and classifiers, pulse detectors for pulsatile signals and an ECG delineator. In addition, it provides a tool for manually reviewing and correcting the results produced by the automatic algorithms. The results obtained can be stored in a Matlab (.MAT file for backup or subsequent processing, or used to create a PDF report.

  11. Common-mode noise cancellation circuit for wearable ECG.

    Science.gov (United States)

    Noro, Mutsumi; Anzai, Daisuke; Wang, Jianqing

    2017-04-01

    Wearable electrocardiogram (ECG) is attracting much attention for monitoring heart diseases in healthcare and medical applications. However, an imbalance usually exists between the contact resistances of sensing electrodes, so that a common mode noise caused by external electromagnetic field can be converted into the ECG detection circuit as a differential mode interference voltage. In this study, after explaining the mechanism of how the common mode noise is converted to a differential mode interference voltage, the authors propose a circuit with cadmium sulphide photo-resistors for cancelling the imbalance between the contact resistances and confirm its validity by simulation experiment. As a result, the authors found that the interference voltage generated at the wearable ECG can be effectively reduced to a sufficient small level.

  12. Combined electrocardiogram and photoplethysmogram measurements as an indicator of objective sleepiness

    International Nuclear Information System (INIS)

    Chua, Chern-Pin; McDarby, Gary; Heneghan, Conor

    2008-01-01

    There is considerable interest in unobtrusive and portable methods of monitoring sleepiness outside the laboratory setting. This study evaluates the usefulness of combined electrocardiogram (ECG) and photoplethysmogram (PPG) measurements for estimating psychomotor vigilance. The psychomotor vigilance test (PVT) was performed at various points over the course of a day, and one channel each of ECG and PPG was recorded simultaneously. Features derived from ECG and PPG were entered into multiple linear regression models to estimate PVT values. A double-loop, subject-independent validation scheme was used to develop and validate the models. We show that features obtained from the RR interval were reasonably useful for estimating absolute PVT levels, but were somewhat inadequate for estimating within-subject PVT changes. Combined ECG and PPG measurements appear to be useful for predicting PVT values, and deserve further investigation for portable sleepiness monitoring

  13. Developing a real time electrocardiogram system using virtual bio-instrumentation.

    Science.gov (United States)

    Elmansouri, Khalifa; Latif, Rachid; Nassiri, Boujamaa; Maoulainine, Fadel Mrabih Rabou

    2014-04-01

    Today bio-manufacturers propose various electrocardiogram (ECG) instruments that have addressed a wide variety of clinical issues. However, the discovery of new applications in ECG devices that provide doctors with the right information at the right time and in the right way will help them to provide a highest quality care possible. In this paper, we focus on the development of an accurate and robust virtual bio-instrument. The important goals of the described project is to provide online new diagnostic informations, an accurate analysis algorithm applied to the acquired signals, data capture from commercial monitors, fast real time ECG acquisition, real time data display and recording of real ECG signals which results in the improvement of data availability. The virtual bio-instrument is validated and tested on the level of robustness, diagnostic accuracy, diagnostic impact and Human - System Interface (HSI) functioning with collaboration of the cardiologists.

  14. Pruning-Based Sparse Recovery for Electrocardiogram Reconstruction from Compressed Measurements

    Directory of Open Access Journals (Sweden)

    Jaeseok Lee

    2017-01-01

    Full Text Available Due to the necessity of the low-power implementation of newly-developed electrocardiogram (ECG sensors, exact ECG data reconstruction from the compressed measurements has received much attention in recent years. Our interest lies in improving the compression ratio (CR, as well as the ECG reconstruction performance of the sparse signal recovery. To this end, we propose a sparse signal reconstruction method by pruning-based tree search, which attempts to choose the globally-optimal solution by minimizing the cost function. In order to achieve low complexity for the real-time implementation, we employ a novel pruning strategy to avoid exhaustive tree search. Through the restricted isometry property (RIP-based analysis, we show that the exact recovery condition of our approach is more relaxed than any of the existing methods. Through the simulations, we demonstrate that the proposed approach outperforms the existing sparse recovery methods for ECG reconstruction.

  15. Electrocardiogram Pattern Recognition and Analysis Based on Artificial Neural Networks and Support Vector Machines: A Review

    Directory of Open Access Journals (Sweden)

    Mario Sansone

    2013-01-01

    Full Text Available Computer systems for Electrocardiogram (ECG analysis support the clinician in tedious tasks (e.g., Holter ECG monitored in Intensive Care Units or in prompt detection of dangerous events (e.g., ventricular fibrillation. Together with clinical applications (arrhythmia detection and heart rate variability analysis, ECG is currently being investigated in biometrics (human identification, an emerging area receiving increasing attention. Methodologies for clinical applications can have both differences and similarities with respect to biometrics. This paper reviews methods of ECG processing from a pattern recognition perspective. In particular, we focus on features commonly used for heartbeat classification. Considering the vast literature in the field and the limited space of this review, we dedicated a detailed discussion only to a few classifiers (Artificial Neural Networks and Support Vector Machines because of their popularity; however, other techniques such as Hidden Markov Models and Kalman Filtering will be also mentioned.

  16. [ECG for non-competitive sports in childhood: strengths and disputes].

    Science.gov (United States)

    Poggi, Elena; Giannattasio, Alessandro; Bolloli, Sara; Beccaria, Andrea; Mezzano, Paola; Rocca, Paola; Del Vecchio, Cecilia

    2016-11-01

    Sport is very important for health promotion and conservation. Active lifestyle and regular exercise reduce cardiovascular disease incidence. The Italian Ministry of Health issued the Law Decree no. 243 (10/18/2014) concerning "guidelines for certification about non-competitive sports" to promote safety in sports. This regulation defines the activities for which a certificate is required, the professional actors involved and the clinical exams to be performed according to the patient's health status. In particular, the Law Decree recommends to perform an electrocardiogram (ECG) "at least once in a lifetime", introducing much greater news into pediatric practice. We proposed a survey evaluating frequency of ECG implementation for non-competitive sports and cardiovascular diseases incidence was administered to 7 Ligurian pediatricians. The number of ECG/year for pediatrician increased from 10 ECG/year to 50 ECG/year with an indication of suitability to non-competitive sports. One case of QT prolongation and 2 cases of type 1 Brugada ECG pattern were diagnosed. In addition, 3 patients had an atrial septal defect and 3 children had a ventricular septal defect. Forty-three percent of the pediatricians considered useful performing the ECG. ECG in children has enhanced the positive effects on the community health. However, it remains to be defined in agreement with scientific societies the age at which to perform ECG, the sports for which ECG is required and the cost-benefit ratio for the National Health System and families.

  17. Extended Kalman smoother with differential evolution technique for denoising of ECG signal.

    Science.gov (United States)

    Panigrahy, D; Sahu, P K

    2016-09-01

    Electrocardiogram (ECG) signal gives a lot of information on the physiology of heart. In reality, noise from various sources interfere with the ECG signal. To get the correct information on physiology of the heart, noise cancellation of the ECG signal is required. In this paper, the effectiveness of extended Kalman smoother (EKS) with the differential evolution (DE) technique for noise cancellation of the ECG signal is investigated. DE is used as an automatic parameter selection method for the selection of ten optimized components of the ECG signal, and those are used to create the ECG signal according to the real ECG signal. These parameters are used by the EKS for the development of the state equation and also for initialization of the parameters of EKS. EKS framework is used for denoising the ECG signal from the single channel. The effectiveness of proposed noise cancellation technique has been evaluated by adding white, colored Gaussian noise and real muscle artifact noise at different SNR to some visually clean ECG signals from the MIT-BIH arrhythmia database. The proposed noise cancellation technique of ECG signal shows better signal to noise ratio (SNR) improvement, lesser mean square error (MSE) and percent of distortion (PRD) compared to other well-known methods.

  18. Effect of electrocardiogram interference on cortico-cortical connectivity analysis and a possible solution.

    Science.gov (United States)

    Govindan, R B; Kota, Srinivas; Al-Shargabi, Tareq; Massaro, An N; Chang, Taeun; du Plessis, Adre

    2016-09-01

    Electroencephalogram (EEG) signals are often contaminated by the electrocardiogram (ECG) interference, which affects quantitative characterization of EEG. We propose null-coherence, a frequency-based approach, to attenuate the ECG interference in EEG using simultaneously recorded ECG as a reference signal. After validating the proposed approach using numerically simulated data, we apply this approach to EEG recorded from six newborns receiving therapeutic hypothermia for neonatal encephalopathy. We compare our approach with an independent component analysis (ICA), a previously proposed approach to attenuate ECG artifacts in the EEG signal. The power spectrum and the cortico-cortical connectivity of the ECG attenuated EEG was compared against the power spectrum and the cortico-cortical connectivity of the raw EEG. The null-coherence approach attenuated the ECG contamination without leaving any residual of the ECG in the EEG. We show that the null-coherence approach performs better than ICA in attenuating the ECG contamination without enhancing cortico-cortical connectivity. Our analysis suggests that using ICA to remove ECG contamination from the EEG suffers from redistribution problems, whereas the null-coherence approach does not. We show that both the null-coherence and ICA approaches attenuate the ECG contamination. However, the EEG obtained after ICA cleaning displayed higher cortico-cortical connectivity compared with that obtained using the null-coherence approach. This suggests that null-coherence is superior to ICA in attenuating the ECG interference in EEG for cortico-cortical connectivity analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. An MLP neural network for ECG noise removal based on Kalman filter.

    Science.gov (United States)

    Moein, Sara

    2010-01-01

    In this paper, application of Artificial Neural Network (ANN) for electrocardiogram (ECG) signal noise removal has been investigated. First, 100 number of ECG signals are selected from Physikalisch-Technische Bundesanstalt (PTB) database and Kalman filter is applied to remove their low pass noise. Then a suitable dataset based on denoised ECG signal is configured and used to a Multilayer Perceptron (MLP) neural network to be trained. Finally, results and experiences are discussed and the effect of changing different parameters for MLP training is shown.

  20. A low-power asynchronous ECG acquisition system in CMOS technology.

    Science.gov (United States)

    Hwang, Sungkil; Trakimas, Michael; Sonkusale, Sameer

    2010-01-01

    An asynchronous electrocardiogram (ECG) acquisition system is presented for wearable ambulatory monitoring. The proposed system consists of a low noise front-end amplifier (AFE) with tunable bandwidth, an asynchronous analog-to-digital converter (ADC), and digital signal processing (DSP). Data compression is achieved by the inherent signal dependent sampling rate of the asynchronous architecture. This makes the system attractive for compact wearable ECG monitoring applications. The AFE and ADC were fabricated in a 0.18 microm CMOS technology and consume a total of 79 microW. Measured results demonstrating ECG monitoring are presented.

  1. Three-dimensional surface reconstruction imaging for evaluation of congenital heart disease from ECG-triggered MR images

    International Nuclear Information System (INIS)

    Vannier, M.W.; Laschinger, J.; Knapp, R.H.; Gutierrez, F.R.; Gronnemeyer, S.A.

    1987-01-01

    Three-dimensional surface reconstruction images of the heart and great vessels were produced from contiguous sequences of electrocardiographically triggered MR images in 25 patients with congenital heart disease and in three healthy subjects. The imaging data were semiautomatically processed to separate the epicardial and endocardial surfaces and to define the outline of the enclosed blood volumes on a section by section basis. Images were obtained at 5-mm intervals in patients aged 3 months to 30 years with anomalies of the great vessels, tetralogy of Fallot, septal defects, pulmonary atresia, and other congenital heart malformations. The results were used to facilitate the surgical treatment of these patients and were compared with echocardiographic and cineradiographic studies, and with surgical findings or pathologic specimens. These surface reconstruction images were useful for communicating the results of diagnostic examinations to cardiac surgeons, for sizing and location of intracardiac defects, for imaging the pulmonary venous drainage, and for assessing regional and global function

  2. Biometrics for Emotion Detection (BED): Exploring the combination of Speech and ECG

    NARCIS (Netherlands)

    Schut, Marleen H.; Tuinenbreijer, Kees; van den Broek, Egon; Westerink, Joyce H.D.M.; Kim, Jonghwa; Karjalainen, Pasi

    2010-01-01

    The paradigm Biometrics for Emotion Detection (BED) is introduced, which enables unobtrusive emotion recognition, taking into account varying environments. It uses the electrocardiogram (ECG) and speech, as a powerful but rarely used combination to unravel people’s emotions. BED was applied in two

  3. Intrapartum fetal monitoring by ST-analysis of the fetal ECG

    NARCIS (Netherlands)

    Westerhuis, M.E.M.H.

    2010-01-01

    Objective Intrapartum fetal monitoring aims to identify fetuses at risk for neonatal and long-term injury due to asphyxia. To serve this purpose, cardiotocography (CTG) combined with ST-analysis of the fetal electrocardiogram (ECG), which is a relatively new method, may be used. The main aim of this

  4. The electrocardiogram of the Humpback Whale (Megaptera novaeangliae), with specific reference to atrioventricular transmission and ventricular excitation

    NARCIS (Netherlands)

    Meijler, F.L.; Wittkampf, Wittkampf, F.H.M.; Brennen, K.R.; Baker, V.; Wassenaar, C.; Bakken, E.E.

    1992-01-01

    The objective of the study was to record the electrocardiogram (ECG) of a large whale to obtain crucial data for comparative electrophysiologic analysis. The data were needed to establish the mismatch between heart size and PR interval and QRS duration in mammals. In the waters off the coast of

  5. Immediate rule-out of acute myocardial infarction using electrocardiogram and baseline high-sensitivity troponin I

    DEFF Research Database (Denmark)

    Neumann, Johannes Tobias; Sörensen, Nils Arne; Ojeda, Francisco

    2017-01-01

    AIMS: Serial measurements of high-sensitivity troponin are used to rule out acute myocardial infarction (AMI) with an assay specific cutoff at the 99th percentile. Here, we evaluated the performance of a single admission troponin with a lower cutoff combined with a low risk electrocardiogram (ECG...

  6. Physics-driven Spatiotemporal Regularization for High-dimensional Predictive Modeling: A Novel Approach to Solve the Inverse ECG Problem

    Science.gov (United States)

    Yao, Bing; Yang, Hui

    2016-12-01

    This paper presents a novel physics-driven spatiotemporal regularization (STRE) method for high-dimensional predictive modeling in complex healthcare systems. This model not only captures the physics-based interrelationship between time-varying explanatory and response variables that are distributed in the space, but also addresses the spatial and temporal regularizations to improve the prediction performance. The STRE model is implemented to predict the time-varying distribution of electric potentials on the heart surface based on the electrocardiogram (ECG) data from the distributed sensor network placed on the body surface. The model performance is evaluated and validated in both a simulated two-sphere geometry and a realistic torso-heart geometry. Experimental results show that the STRE model significantly outperforms other regularization models that are widely used in current practice such as Tikhonov zero-order, Tikhonov first-order and L1 first-order regularization methods.

  7. Characteristics of the reindeer electrocardiogram

    Directory of Open Access Journals (Sweden)

    Jouni Timisjärvi

    1982-05-01

    Full Text Available The electrocardiogram (ECG provides reliable information about heart rate, initiation of heart beat and also, to some degree, indirect evidence on the functional state of the heart muscle. A wide range of such information is readily obtainable from conventional scalar leads, even if the records are limited to a single plane. The present investigation deals with the normal reindeer ECG in the frontal plane. The technique used is the scalar recording technique based on the Einthovenian postulates. The P wave was positive in leads II, III and aVF, negative in lead aVL and variable in leads I and aVR. The direction of the P vector was 60 to 120°. The QRS complex was variable. The most common forms of QRS complex were R and rS in leads I and aVR; R, Rs and rS in lead aVL and Qr or qR in other leads. The most common direction of the QRS vector was 240 to 300°. The T wave was variable. The duration of various intervals and deflection depended on heart rate.Elektrokardiogram på ren.Abstract in Swedish / Sammandrag: Elektrokardiogramet (EKG ger tillförlitliga uppgifter om hjärtfrekvens, retledning och, indirekt, delvis även om hjärtmuskelns funktionell tillstånd. Största delen av denna information fås med normal skalar koppling även om registrering sker i ett plan. I detta arbete har renens normala EKG i frontalplanet undersökts. Kopplingarna har baserats på Einthovs postulat. P-vågen var riktad uppåt i koppling II, III och aVF, nedåt i koppling aVL och den varierade i koppling I och aVR. P-vektorns riktning var 60 - 120°. QRS-komplexet varierade. De vanligaste formerna var R och rS i koppling I och aVR; R, Rs och rS i koppling aVL och Qr eller qR i andra kopplingar. Vanligen var QRS-vektorns riktning 240 - 300°. T-vågen varierade. Awikelserna och intervallernas längd var beroende av hiärtfrekvenssen.Poron sydänsähkökäyrän ominaisuuksia.Abstract in Finnish / Yhteenveto: Sydänsähkökäyrästä saadaan luotettavaa tietoa syd

  8. Performance of human body communication-based wearable ECG with capacitive coupling electrodes.

    Science.gov (United States)

    Sakuma, Jun; Anzai, Daisuke; Wang, Jianqing

    2016-09-01

    Wearable electrocardiogram (ECG) is attracting much attention in daily healthcare applications, and human body communication (HBC) technology provides an evident advantage in making the sensing electrodes of ECG also working for transmission through the human body. In view of actual usage in daily life, however, non-contact electrodes to the human body are desirable. In this Letter, the authors discussed the ECG circuit structure in the HBC-based wearable ECG for removing the common mode noise when employing non-contact capacitive coupling electrodes. Through the comparison of experimental results, they have shown that the authors' proposed circuit structure with the third electrode directly connected to signal ground can provide an effect on common mode noise reduction similar to the usual drive-right-leg circuit, and a sufficiently good acquisition performance of ECG signals.

  9. ECG Signal Processing, Classification and Interpretation A Comprehensive Framework of Computational Intelligence

    CERN Document Server

    Pedrycz, Witold

    2012-01-01

    Electrocardiogram (ECG) signals are among the most important sources of diagnostic information in healthcare so improvements in their analysis may also have telling consequences. Both the underlying signal technology and a burgeoning variety of algorithms and systems developments have proved successful targets for recent rapid advances in research. ECG Signal Processing, Classification and Interpretation shows how the various paradigms of Computational Intelligence, employed either singly or in combination, can produce an effective structure for obtaining often vital information from ECG signals. Neural networks do well at capturing the nonlinear nature of the signals, information granules realized as fuzzy sets help to confer interpretability on the data and evolutionary optimization may be critical in supporting the structural development of ECG classifiers and models of ECG signals. The contributors address concepts, methodology, algorithms, and case studies and applications exploiting the paradigm of Comp...

  10. Educational Software Applied in Teaching Electrocardiogram: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Paulo A. I. Pontes

    2018-01-01

    Full Text Available Background. The electrocardiogram (ECG is the most used diagnostic tool in medicine; in this sense, it is essential that medical undergraduates learn how to interpret it correctly while they are still on training. Naturally, they go through classic learning (e.g., lectures and speeches. However, they are not often efficiently trained in analyzing ECG results. In this regard, methodologies such as other educational support tools in medical practice, such as educational software, should be considered a valuable approach for medical training purposes. Methods. We performed a literature review in six electronic databases, considering studies published before April 2017. The resulting set comprises 2,467 studies. From this collection, 12 studies have been selected, initially, whereby we carried out a snowballing process to identify other relevant studies through the reference lists of these studies, resulting in five relevant studies, making up a total of 17 articles that passed all stages and criteria. Results. The results show that 52.9% of software types were tutorial and 58.8% were designed to be run locally on a computer. The subjects were discussed together with a greater focus on the teaching of electrophysiology and/or cardiac physiology, identifying patterns of ECG and/or arrhythmias. Conclusions. We found positive results with the introduction of educational software for ECG teaching. However, there is a clear need for using higher quality research methodologies and the inclusion of appropriate controls, in order to obtain more precise conclusions about how beneficial the inclusion of such tools can be for the practices of ECG interpretation.

  11. Changes in canine electrocardiogram values from three thermal floors in Cundinamarca, Colombia

    OpenAIRE

    Marta Elena Sánchez Klinge; Carlos Alberto Venegas Cortés

    2008-01-01

    The electrocardiogram is a written register of electric changes that take place in the heart during a heart cycle. The voltage changes are the result of depolarization and repolarization of heart muscle fibers that produce electric changes able to reach body surface and that are detected by electrodes connected to a galvanometer called electrocardiograph. Heart problems are detected with the electrocardiogram, but it is necessary to know the normal values of canine electrocardiogram in a trop...

  12. Justification of an introductory electrocardiogram teaching mnemonic by demonstration of its prognostic value.

    Science.gov (United States)

    Soofi, Muhammad; Yong, Celina; Froelicher, Victor

    2014-12-01

    With diminishing time afforded to electrocardiography in the medical curriculum, we have found Sibbitt's simple mnemonic, the Diagonal Line Lead Rule, for a pattern recognition approach to 12-lead electrocardiogram (ECG) interpretation to be appreciated by students. However, it still lacks universal acceptance because its clinical utility has not been documented. The study objective was to demonstrate the clinical utility of the Diagonal Line Lead ECG Teaching Rule. After excluding ECGs of high-risk patients with Wolff-Parkinson-White syndrome and QRS durations greater than 120 ms, the initial ECGs of the remaining 43,798 patients were scored according to the Diagonal Line Lead Rule. A total of 45,497 patients from the Veterans Affairs Palo Alto Healthcare System were referred for a routine initial resting ECG from 1987 to 1999. We determined cardiovascular mortality with 8 years of follow-up. In patients with normal QRS duration, diagnostic Q-wave or T-wave inversions isolated to the diagonal line leads showed no increased risk of cardiovascular death. Q-wave or T-wave inversion in any other lead was significantly associated with cardiovascular death with an age-adjusted Cox hazard of 2.6 (confidence interval, 2.4-2.8; P mnemonic for 12-lead ECG interpretation that can facilitate ECG teaching and interpretation. Published by Elsevier Inc.

  13. Screening electrocardiograms in psychiatric research: implications for physicians and healthy volunteers.

    Science.gov (United States)

    Pavletic, A J; Pao, M; Pine, D S; Luckenbaugh, D A; Rosing, D R

    2014-01-01

    While there is controversy regarding utility of screening electrocardiograms (ECGs) in competitive athletes and children exposed to psychostimulants, there is no data on the use of screening ECGs in psychiatric research. We aimed to examine the prevalence and clinical significance of ECG abnormalities and their impact on eligibility for studies. We analysed 500 consecutive ECG reports from physically healthy volunteers who had a negative cardiac history, normal cardiovascular examination and no other significant medical illnesses. For the purpose of this report, all ECGs were over-read by one cardiologist. The mean age of our cohort was 28.3 ± 8.0 years. A total of 112 (22.4%) ECGs were reported as abnormal (14.2%) or borderline (8.2%). These abnormalities were considered clinically insignificant in all but eight subjects (1.6%) who underwent evaluation with an echocardiogram. All echocardiograms were normal. No subject was excluded from studies. After the over-reading, no abnormalities or isolated bradycardia were present in 37 of 112 (33%) ECGs that were initially reported as abnormal or borderline, while minor abnormalities were found in 7 of 204 (3.4%) ECGs that were reported as normal. Although screening ECGs did not detect significant cardiac pathology or affect eligibility for our studies, over 20% of subjects were labelled as having an abnormal or borderline ECG which was incorrect in one-third of cases. Strategies to minimise unintended consequences of screening are discussed. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  14. Use of concept maps to promote electrocardiogram diagnosis learning in undergraduate medical students

    Science.gov (United States)

    Dong, Ruimin; Yang, Xiaoyan; Xing, Bangrong; Zou, Zihao; Zheng, Zhenda; Xie, Xujing; Zhu, Jieming; Chen, Lin; Zhou, Hanjian

    2015-01-01

    Concept mapping is an effective method in teaching and learning, however this strategy has not been evaluated among electrocardiogram (ECG) diagnosis learning. This study explored the use of concept maps to assist ECG study, and sought to analyze whether this method could improve undergraduate students’ ECG interpretation skills. There were 126 undergraduate medical students who were randomly selected and assigned to two groups, group A (n = 63) and group B (n = 63). Group A was taught to use concept maps to learn ECG diagnosis, while group B was taught by traditional methods. After the course, all of the students were assessed by having an ECG diagnostic test. Quantitative data which comprised test score and ECG features completion index was compared by using the unpaired Student’s t-test between the two groups. Further, a feedback questionnaire on concept maps used was also completed by group A, comments were evaluated by a five-point Likert scale. The test scores of ECGs interpretation was 7.36 ± 1.23 in Group A and 6.12 ± 1.39 in Group B. A significant advantage (P = 0.018) of concept maps was observed in ECG interpretation accuracy. No difference in the average ECG features completion index was observed between Group A (66.75 ± 15.35%) and Group B (62.93 ± 13.17%). According qualitative analysis, majority of students accepted concept maps as a helpful tool. Difficult to learn at the beginning and time consuming are the two problems in using this method, nevertheless most of the students indicated to continue using it. Concept maps could be a useful pedagogical tool in enhancing undergraduate medical students’ ECG interpretation skills. Furthermore, students indicated a positive attitude to it, and perceived it as a resource for learning. PMID:26221331

  15. Estimating the measuring sensitivity of unipolar and bipolar ECG with lead field method and FDM models.

    Science.gov (United States)

    Puurtinen, Merja; Viik, Jari; Takano, Noriyuki; Malmivuo, Jaakko; Hyttinen, Jari

    2009-05-01

    New portable electrocardiogram (ECG) measurement systems are emerging into market. Some use nonstandard bipolar electrode montage and sometimes very small interelectrode distances to improve the usability of the system. Modeling could provide a straightforward method to test new electrode systems. The aim of this study was to assess whether modeling the electrodes' measuring sensitivity with lead field method can provide a simple tool for testing a number of new electrode locations. We evaluated whether the actual ECG signal strength can be estimated by lead fields with two realistic 3D finite difference method (FDM) thorax models. We compared the modeling results to clinical body surface potential map (BSPM) data from 236 normal patients and studied 117 unipolar and 42 bipolar leads. In the case of unipolar electrodes the modeled measuring sensitivities correlated well with the clinical data (r=0.86, N=117, p<0.05). In the case of bipolar electrodes the correlation was moderate (r=0.62 between Model 1 and clinical data, r=0.71 between Model 2 and clinical data, N=42 and p<0.05 for both). Based on this we can conclude that lead field analysis based on realistic thorax models provides a good initial prediction for designing new electrode montages and measurement systems.

  16. Correlation between ECG changes and early left ventricular remodeling in preadolescent footballers.

    Science.gov (United States)

    Zdravkovic, M; Milovanovic, B; Hinic, S; Soldatovic, I; Durmic, T; Koracevic, G; Prijic, S; Markovic, O; Filipovic, B; Lovic, D

    2017-03-01

    The aim of this study was to assess the early electrocardiogram (ECG) changes induced by physical training in preadolescent elite footballers. This study included 94 preadolescent highly trained male footballers (FG) competing in Serbian Football League (minimum of 7 training hours/week) and 47 age-matched healthy male controls (less than 2 training hours/week) (CG). They were screened by ECG and echocardiography at a tertiary referral cardio center. Sokolow-Lyon index was used as a voltage electrocardiographic criterion for left ventricular hypertrophy diagnosis. Characteristic ECG intervals and voltage were compared and reference range was given for preadolescent footballers. Highly significant differences between FG and CG were registered in all ECG parameters: P-wave voltage (p ECG sum of S V 1-2  + R V 5-6 (p  0.05). During 6-year follow-up period, there was no adverse cardiac event in these footballers. None of them expressed pathological ECG changes. Benign ECG changes are presented in the early stage of athlete's heart remodeling, but they are not related to pathological ECG changes and they should be regarded as ECG pattern of LV remodeling.

  17. Arrhythmia Classification Based on Multi-Domain Feature Extraction for an ECG Recognition System.

    Science.gov (United States)

    Li, Hongqiang; Yuan, Danyang; Wang, Youxi; Cui, Dianyin; Cao, Lu

    2016-10-20

    Automatic recognition of arrhythmias is particularly important in the diagnosis of heart diseases. This study presents an electrocardiogram (ECG) recognition system based on multi-domain feature extraction to classify ECG beats. An improved wavelet threshold method for ECG signal pre-processing is applied to remove noise interference. A novel multi-domain feature extraction method is proposed; this method employs kernel-independent component analysis in nonlinear feature extraction and uses discrete wavelet transform to extract frequency domain features. The proposed system utilises a support vector machine classifier optimized with a genetic algorithm to recognize different types of heartbeats. An ECG acquisition experimental platform, in which ECG beats are collected as ECG data for classification, is constructed to demonstrate the effectiveness of the system in ECG beat classification. The presented system, when applied to the MIT-BIH arrhythmia database, achieves a high classification accuracy of 98.8%. Experimental results based on the ECG acquisition experimental platform show that the system obtains a satisfactory classification accuracy of 97.3% and is able to classify ECG beats efficiently for the automatic identification of cardiac arrhythmias.

  18. Usefulness of ST elevation score by using vector-projected virtual 187-channel ECG for risk stratification in patients with Brugada-type ECG pattern

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    Shoko Ishikawa

    2012-08-01

    Conclusion: The ST elevation score in VP-ECG objectively documented the degree of ST elevation in surface ECG in Brugada-type ECG patterns. The ST-elevation score might be useful for risk stratification in patients with asymptomatic Brugada syndrome.

  19. ECG monitoring in syncope.

    Science.gov (United States)

    Ruwald, Martin H; Zareba, Wojciech

    2013-01-01

    Electrocardiographic (ECG) monitoring is a well-established procedure in the work-up of patients with syncope or for diagnosing arrhythmias. The investigation of syncope remains, however, challenging and physicians have an increasing armamentarium of diagnostic tools available and with advances in technology the role of these tools has to be continuously evaluated. The gold standard for the diagnosis of syncope is a symptom-ECG correlation, and while many studies have investigated the use and indications of both short-term and long-term monitoring; there is still some uncertainty in their clinical utility and practical approach. The use of ECG monitoring and other diagnostic tools is often subject to a "shot-gun approach" rather than a strict guideline algorithm. A systematic approach and selection of ECG monitoring tools helps permit an effective usage of the limited health care resources available for the management of unexplained syncope. In this review we aim to focus and clarify the role of short-term (Holter and external loop recorders) and long-term (implantable loop recorders) ECG monitoring in the diagnosis and management of patients with unexplained syncope. © 2013.

  20. Human Authentication Based on ECG Waves Using Radon Transform

    Science.gov (United States)

    Hegde, Chetana; Prabhu, H. Rahul; Sagar, D. S.; Shenoy, P. Deepa; Venugopal, K. R.; Patnaik, L. M.

    Automated security is one of the major concerns of modern times. Secure and reliable authentication systems are in great demand. A biometric trait like electrocardiogram (ECG) of a person is unique and secure. In this paper, we propose a human authentication system based on ECG waves considering a plotted ECG wave signal as an image. The Radon Transform is applied on the preprocessed ECG image to get a radon image consisting of projections for θ varying from 0 o to 180 o . The pairwise distance between the columns of Radon image is computed to get a feature vector. Correlation Coefficient between feature vector stored in the database and that of input image is computed to check the authenticity of a person. Then the confusion matrix is generated to find False Acceptance Ratio (FAR) and False Rejection Ratio (FRR). This methodology of authentication is tested on ECG wave data set of 105 individuals taken from Physionet QT Database. The proposed authentication system is found to have FAR of about 3.19% and FRR of about 0.128%. The overall accuracy of the system is found to be 99.85%.

  1. Privacy-Preserving Electrocardiogram Monitoring for Intelligent Arrhythmia Detection

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    Junggab Son

    2017-06-01

    Full Text Available Long-term electrocardiogram (ECG monitoring, as a representative application of cyber-physical systems, facilitates the early detection of arrhythmia. A considerable number of previous studies has explored monitoring techniques and the automated analysis of sensing data. However, ensuring patient privacy or confidentiality has not been a primary concern in ECG monitoring. First, we propose an intelligent heart monitoring system, which involves a patient-worn ECG sensor (e.g., a smartphone and a remote monitoring station, as well as a decision support server that interconnects these components. The decision support server analyzes the heart activity, using the Pan–Tompkins algorithm to detect heartbeats and a decision tree to classify them. Our system protects sensing data and user privacy, which is an essential attribute of dependability, by adopting signal scrambling and anonymous identity schemes. We also employ a public key cryptosystem to enable secure communication between the entities. Simulations using data from the MIT-BIH arrhythmia database demonstrate that our system achieves a 95.74% success rate in heartbeat detection and almost a 96.63% accuracy in heartbeat classification, while successfully preserving privacy and securing communications among the involved entities.

  2. Mobile Messaging Services-Based Personal Electrocardiogram Monitoring System

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    Ashraf A. Tahat

    2009-01-01

    Full Text Available A mobile monitoring system utilizing Bluetooth and mobile messaging services (MMS/SMSs with low-cost hardware equipment is proposed. A proof of concept prototype has been developed and implemented to enable transmission of an Electrocardiogram (ECG signal and body temperature of a patient, which can be expanded to include other vital signs. Communication between a mobile smart-phone and the ECG and temperature acquisition apparatus is implemented using the popular personal area network standard specification Bluetooth. When utilizing MMS for transmission, the mobile phone plots the received ECG signal and displays the temperature using special application software running on the client mobile phone itself, where the plot can be captured and saved as an image before transmission. Alternatively, SMS can be selected as a transmission means, where in this scenario, dedicated application software is required at the receiving device. The experimental setup can be operated for monitoring from anywhere in the globe covered by a cellular network that offers data services.

  3. A 58 nW ECG ASIC With Motion-Tolerant Heartbeat Timing Extraction for Wearable Cardiovascular Monitoring.

    Science.gov (United States)

    Da He, David; Sodini, Charles G

    2015-06-01

    An ASIC for wearable cardiovascular monitoring is implemented using a topology that takes advantage of the electrocardiogram's (ECG) waveform to replace the traditional ECG instrumentation amplifier, ADC, and signal processor with a single chip solution. The ASIC can extract heartbeat timings in the presence of baseline drift, muscle artifact, and signal clipping. The circuit can operate with ECGs ranging from the chest location to remote locations where the ECG magnitude is as low as 30 μV. Besides heartbeat detection, a midpoint estimation method can accurately extract the ECG R-wave timing, enabling the calculations of heart rate variability. With 58 nW of power consumption at 0.8 V supply voltage and 0.76 mm (2) of active die area in standard 0.18 μm CMOS technology, the ECG ASIC is sufficiently low power and compact to be suitable for long term and wearable cardiovascular monitoring applications under stringent battery and size constraints.

  4. An ECG simulator for generating maternal-foetal activity mixtures on abdominal ECG recordings.

    Science.gov (United States)

    Behar, Joachim; Andreotti, Fernando; Zaunseder, Sebastian; Li, Qiao; Oster, Julien; Clifford, Gari D

    2014-08-01

    Accurate foetal electrocardiogram (FECG) morphology extraction from non-invasive sensors remains an open problem. This is partly due to the paucity of available public databases. Even when gold standard information (i.e derived from the scalp electrode) is present, the collection of FECG can be problematic, particularly during stressful or clinically important events.In order to address this problem we have introduced an FECG simulator based on earlier work on foetal and adult ECG modelling. The open source foetal ECG synthetic simulator, fecgsyn, is able to generate maternal-foetal ECG mixtures with realistic amplitudes, morphology, beat-to-beat variability, heart rate changes and noise. Positional (rotation and translation-related) movements in the foetal and maternal heart due to respiration, foetal activity and uterine contractions were also added to the simulator.The simulator was used to generate some of the signals that were part of the 2013 PhysioNet Computing in Cardiology Challenge dataset and has been posted on Physionet.org (together with scripts to generate realistic scenarios) under an open source license. The toolbox enables further research in the field and provides part of a standard for industry and regulatory testing of rare pathological scenarios.

  5. ECG-based 4D-dose reconstruction of cardiac arrhythmia ablation with carbon ion beams: application in a porcine model.

    Science.gov (United States)

    Richter, Daniel; Lehmann, H Immo; Eichhorn, Anna; Constantinescu, Anna M; Kaderka, Robert; Prall, Matthias; Lugenbiel, Patrick; Takami, Mitsuru; Thomas, Dierk; Bert, Christoph; Durante, Marco; Packer, Douglas L; Graeff, Christian

    2017-08-04

    Noninvasive ablation of cardiac arrhythmia by scanned particle radiotherapy is highly promising, but especially challenging due to cardiac and respiratory motion. Irradiations for catheter-free ablation in intact pigs were carried out at the GSI Helmholtz Center in Darmstadt using scanned carbon ions. Here, we present real-time electrocardiogram (ECG) data to estimate time-resolved (4D) delivered dose. For 11 animals, surface ECGs and temporal structure of beam delivery were acquired during irradiation. R waves were automatically detected from surface ECGs. Pre-treatment ECG-triggered 4D-CT phases were synchronized to the R-R interval. 4D-dose calculation was performed using GSI's in-house 4D treatment planning system. Resulting dose distributions were assessed with respect to coverage (D95 and V95), heterogeneity (HI  =  D5-D95) and normal tissue exposure. Final results shown here were performed offline, but first calculations were started shortly after irradiation The D95 for TV and PTV was above 95% for 10 and 8 out of 11 animals, respectively. HI was reduced for PTV versus TV volumes, especially for some of the animals targeted at the atrioventricular junction, indicating residual interplay effects due to cardiac motion. Risk structure exposure was comparable to static and 4D treatment planning simulations. ECG-based 4D-dose reconstruction is technically feasible in a patient treatment-like setting. Further development of the presented approach, such as real-time dose calculation, may contribute to safe, successful treatments using scanned ion beams for cardiac arrhythmia ablation.

  6. ECG-based 4D-dose reconstruction of cardiac arrhythmia ablation with carbon ion beams: application in a porcine model

    Science.gov (United States)

    Richter, Daniel; Immo Lehmann, H.; Eichhorn, Anna; Constantinescu, Anna M.; Kaderka, Robert; Prall, Matthias; Lugenbiel, Patrick; Takami, Mitsuru; Thomas, Dierk; Bert, Christoph; Durante, Marco; Packer, Douglas L.; Graeff, Christian

    2017-09-01

    Noninvasive ablation of cardiac arrhythmia by scanned particle radiotherapy is highly promising, but especially challenging due to cardiac and respiratory motion. Irradiations for catheter-free ablation in intact pigs were carried out at the GSI Helmholtz Center in Darmstadt using scanned carbon ions. Here, we present real-time electrocardiogram (ECG) data to estimate time-resolved (4D) delivered dose. For 11 animals, surface ECGs and temporal structure of beam delivery were acquired during irradiation. R waves were automatically detected from surface ECGs. Pre-treatment ECG-triggered 4D-CT phases were synchronized to the R-R interval. 4D-dose calculation was performed using GSI’s in-house 4D treatment planning system. Resulting dose distributions were assessed with respect to coverage (D95 and V95), heterogeneity (HI  =  D5-D95) and normal tissue exposure. Final results shown here were performed offline, but first calculations were started shortly after irradiation The D95 for TV and PTV was above 95% for 10 and 8 out of 11 animals, respectively. HI was reduced for PTV versus TV volumes, especially for some of the animals targeted at the atrioventricular junction, indicating residual interplay effects due to cardiac motion. Risk structure exposure was comparable to static and 4D treatment planning simulations. ECG-based 4D-dose reconstruction is technically feasible in a patient treatment-like setting. Further development of the presented approach, such as real-time dose calculation, may contribute to safe, successful treatments using scanned ion beams for cardiac arrhythmia ablation.

  7. Fetal Electrocardiogram Extraction and Analysis Using Adaptive Noise Cancellation and Wavelet Transformation Techniques.

    Science.gov (United States)

    Sutha, P; Jayanthi, V E

    2017-12-08

    Birth defect-related demise is mainly due to congenital heart defects. In the earlier stage of pregnancy, fetus problem can be identified by finding information about the fetus to avoid stillbirths. The gold standard used to monitor the health status of the fetus is by Cardiotachography(CTG), cannot be used for long durations and continuous monitoring. There is a need for continuous and long duration monitoring of fetal ECG signals to study the progressive health status of the fetus using portable devices. The non-invasive method of electrocardiogram recording is one of the best method used to diagnose fetal cardiac problem rather than the invasive methods.The monitoring of the fECG requires development of a miniaturized hardware and a efficient signal processing algorithms to extract the fECG embedded in the mother ECG. The paper discusses a prototype hardware developed to monitor and record the raw mother ECG signal containing the fECG and a signal processing algorithm to extract the fetal Electro Cardiogram signal. We have proposed two methods of signal processing, first is based on the Least Mean Square (LMS) Adaptive Noise Cancellation technique and the other method is based on the Wavelet Transformation technique. A prototype hardware was designed and developed to acquire the raw ECG signal containing the mother and fetal ECG and the signal processing techniques were used to eliminate the noises and extract the fetal ECG and the fetal Heart Rate Variability was studied. Both the methods were evaluated with the signal acquired from a fetal ECG simulator, from the Physionet database and that acquired from the subject. Both the methods are evaluated by finding heart rate and its variability, amplitude spectrum and mean value of extracted fetal ECG. Also the accuracy, sensitivity and positive predictive value are also determined for fetal QRS detection technique. In this paper adaptive filtering technique uses Sign-sign LMS algorithm and wavelet techniques with

  8. Diagnostic Yield of Echocardiography in Syncope Patients with Normal ECG

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    Nai-Lun Chang

    2016-01-01

    Full Text Available Aim. This study aimed to assess the role of echocardiography as a diagnostic tool in evaluating syncope patients with normal versus abnormal electrocardiogram. Methods. We conducted a retrospective study of 468 patients who were admitted with syncope in 2011 at St. Joseph’s Regional Medical Center, Paterson, NJ. Hospital records and patient charts, including initial emergency room history and physical, were carefully reviewed. Patients were separated into normal versus abnormal electrocardiogram groups and then further divided as normal versus abnormal echocardiogram groups. Causes of syncope were extrapolated after reviewing all test results and records of consultations. Results. Three hundred twelve of the total patients (68.6% had normal ECG. Two-thirds of those patients had echocardiograms; 11 patients (5.7% had abnormal echo results. Of the aforementioned patients, three patients had previous documented history of severe aortic stenosis on prior echocardiograms. The remaining eight had abnormal but nondiagnostic echocardiographic findings. Echocardiography was done in 93 of 147 patients with abnormal ECG (63.2%. Echo was abnormal in 27 patients (29%, and the findings were diagnostic in 6.5% patients. Conclusions. This study demonstrates that echocardiogram was not helpful in establishing a diagnosis of syncope in patients with normal ECG and normal physical examination.

  9. New ideas for teaching electrocardiogram interpretation and improving classroom teaching content

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    Zeng R

    2015-02-01

    Full Text Available Rui Zeng,1 Rong-Zheng Yue,2 Chun-Yu Tan,3 Qin Wang,4 Pu Kuang,5 Pan-Wen Tian,6 Chuan Zuo3 1Department of Cardiovascular Diseases, 2Department of Nephrology, 3Department of Rheumatology and Immunology, 4Department of Endocrinology, 5Department of Hematology, 6Department of Respiratory Diseases, West China Hospital, School of Clinic Medicine, Sichuan University, Chengdu, People’s Republic of China Background: Interpreting an electrocardiogram (ECG is not only one of the most important parts of diagnostics but also one of the most difficult areas to teach. Owing to the abstract nature of the basic theoretical knowledge of the ECG, its scattered characteristics, and tedious and difficult-to-remember subject matter, teaching how to interpret ECGs is as difficult for teachers to teach as it is for students to learn. In order to enable medical students to master basic knowledge of ECG interpretation skills in a limited teaching time, we modified the content used for traditional ECG teaching and now propose a new ECG teaching method called the “graphics-sequence memory method.” Methods: A prospective randomized controlled study was designed to measure the actual effectiveness of ECG learning by students. Two hundred students were randomly placed under a traditional teaching group and an innovative teaching group, with 100 participants in each group. The teachers in the traditional teaching group utilized the traditional teaching outline, whereas the teachers in the innovative teaching group received training in line with the proposed teaching method and syllabus. All the students took an examination in the final semester by analyzing 20 ECGs from real clinical cases and submitted their ECG reports. Results: The average ECG reading time was 32 minutes for the traditional teaching group and 18 minutes for the innovative teaching group. The average ECG accuracy results were 43% for the traditional teaching group and 77% for the innovative teaching

  10. Role of surface electrocardiogram precordial leads in localizing different anatomic sites of ectopic atrial tachycardia arising from lower right atrium in pediatric population.

    Science.gov (United States)

    Allam, Lamyaa Elsayed; Ahmed, Rania Samir; Ghanem, Mazen Tawfik

    2018-01-01

    The study was designed to examine P wave morphology (PWM) in precordial leads (V 1 -V 6 ) during ectopic atrial tachycardia (EAT) originating from low right atrium (RA) to identify the anatomic sites of these foci in children. Twenty-three consecutive pediatric patients (56% females, mean age 8.5 ± 2.5) with EAT originating from the low RA underwent detailed atrial endocardial activation mapping and radiofrequency ablation. PWM during EAT was analyzed using standard 12-lead ECG in relation to successful ablation sites in RA. Ectopic atrial tachycardia originated from coronary sinus ostium (CSo) in 12 patients, nonseptal tricuspid annulus (TA) in five, lower crista terminalis (CT) in three and lower free wall in three. In lead V 1 , PWM showed a positive pattern during EAT originating from CSo (8/12) [91.7% sensitivity, 100% specificity, 100% positive predictive value (PPV), 100% negative predictive value (NPV)]. A negative pattern was observed in EAT originating from lower free wall (1/3) and nonseptal TA (5/5) [50% sensitivity, 100% specificity, 100% PPV, 75% NPV], while isoelectric pattern was in EAT originating from lower CT (3/3) [100% sensitivity, 100% specificity, 100% PPV, 100% NPV]. In leads V 3 -V 6 , PWM showed a negative pattern in at least two consecutive leads during EAT from CSo (12/12), nonseptal TA (5/5) and lower free wall (3/3) while it was positive in EAT originating from lower CT (3/3) [100% sensitivity, 95% specificity, 75% PPV and 100% NPV]. P wave morphology in precordial leads can help differentiate the anatomic sites of EAT from lower RA with high PPVs and NPVs. © 2017 Wiley Periodicals, Inc.

  11. The prevalence of abnormal ECG in trained sportsmen.

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    Malhotra, V K; Singh, Navreet; Bishnoi, R S; Chadha, D S; Bhardwaj, P; Madan, H; Dutta, R; Ghosh, A K; Sengupta, S; Perumal, P

    2015-10-01

    Competitive sports training causes structural and conductive system changes manifesting by various electrocardiographic alterations. We undertook this study to assess the prevalence of abnormal ECG in trained Indian athletes and correlate it with the nature of sports training, that is endurance or strength training. We evaluated a standard resting, lying 12 lead Electrocardiogram (ECG) in 66 actively training Indian athletes. Standard diagnostic criteria were used to define various morphological ECG abnormalities. 33/66 (50%) of the athletes were undertaking endurance training while the other 33 (50%) were involved in a strength-training regimen. Overall 54/66 (81%) sportsmen had significant ECG changes. 68% of these changes were considered as normal training related features, while the remaining 32% were considered abnormal. There were seven common training related ECG changes-Sinus Bradycardia (21%), Sinus Arrhythmia (16%), 1st degree Atrioventricular Heart Block (6%), Type 1 2nd-degree Atrioventicular Heart Block (3%), Incomplete Right bundle branch block (RBBB) (24%), Early Repolarization (42%), Left Ventricular Hypertrophy (LVH) (14%); while three abnormal ECG changes--T-wave inversion (13%), RBBB(4%), Right ventricular hypertrophy (RVH) with strain (29%) were noted. Early repolarization (commonest change), sinus bradycardia, and incomplete RBBB were the commoner features noticed, with a significantly higher presence in the endurance trained athletes. A high proportion of athletes undergoing competitive level sports training are likely to have abnormal ECG recordings. Majority of these are benign, and related to the physiological adaptation to the extreme levels of exertion. These changes are commoner during endurance training (running) than strength training (weightlifting).

  12. Retrospective study of pre-anesthetic electrocardiogram examination of 700 dogs conducted at the Veterinary Hospital of UFMG (2013-2014

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    Ana Flávia Machado Botelho

    2016-02-01

    Full Text Available Abstract: Pre-operative electrocardiograms performed in 700 dogs were analyzed in order to establish correlation between sex, age, indication for surgery, body condition score, breed and weight. Initially a clinical questionnaire was filled out from each owner, including age, breed, sex, weight, clinical history and surgical indication. Dogs above 6 years of age or those showing any kind of cardiac auscultation disturbances were referred to electrocardiogram (ECG evaluation. All ECG were performed and analyzed by the same veterinary specialist. Abnormalities at ECG were founnd in 364 of 700 (52% evaluated dogs, and the most frequent variation was sinus arrhythmia, observed in 293 dogs (25.4%. No significant correlation was found between the electrocardiographic alterations with weight, sex and age of the animals. Therefore ECG should be conducted routinely regardless of age, sex, breed or surgical indication, highlighting its value for determining a safe anesthetic protocol that promotes minimal cardiopulmonary depression and allows rapid post-surgical recovery.

  13. A gender-based analysis of high school athletes using computerized electrocardiogram measurements.

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    Nikhil Kumar

    Full Text Available BACKGROUND: The addition of the ECG to the preparticipation examination (PPE of high school athletes has been a topic for debate. Defining the difference between the high school male and female ECG is crucial to help initiate its implementation in the High School PPE. Establishing the different parameters set for the male and female ECG would help to reduce false positives. We examined the effect of gender on the high school athlete ECG by obtaining and analyzing ECG measurements of high school athletes from Henry M. Gunn High School. METHODS: In 2011 and 2012, computerized Electrocardiograms were recorded and analyzed on 181 athletes (52.5% male; mean age 16.1 ± 1.1 years who participated in 17 different sports. ECG statistics included intervals and durations in all 3 axes (X, Y, Z to calculate 12 lead voltage sums, QRS Amplitude, QT interval, QRS Duration, and the sum of the R wave in V5 and the S Wave in V2 (RS Sum. RESULTS: By computer analysis, we demonstrated that male athletes had significantly greater QRS duration, Q-wave duration, and T wave amplitude. (P<0.05. By contrast, female athletes had a significantly greater QTc interval. (P<0.05. CONCLUSION: The differences in ECG measurements in high school athletes are strongly associated with gender. However, body size does not correlate with the aforementioned ECG measurements. Our tables of the gender-specific parameters can help facilitate the development of a more large scale and in-depth ECG analysis for screening high school athletes in the future.

  14. Impact of teaching and assessment format on electrocardiogram interpretation skills.

    Science.gov (United States)

    Raupach, Tobias; Hanneforth, Nathalie; Anders, Sven; Pukrop, Tobias; Th J ten Cate, Olle; Harendza, Sigrid

    2010-07-01

    Interpretation of the electrocardiogram (ECG) is a core clinical skill that should be developed in undergraduate medical education. This study assessed whether small-group peer teaching is more effective than lectures in enhancing medical students' ECG interpretation skills. In addition, the impact of assessment format on study outcome was analysed. Two consecutive cohorts of Year 4 medical students (n=335) were randomised to receive either traditional ECG lectures or the same amount of small-group, near-peer teaching during a 6-week cardiorespiratory course. Before and after the course, written assessments of ECG interpretation skills were undertaken. Whereas this final assessment yielded a considerable amount of credit points for students in the first cohort, it was merely formative in nature for the second cohort. An unannounced retention test was applied 8 weeks after the end of the cardiovascular course. A significant advantage of near-peer teaching over lectures (effect size 0.33) was noted only in the second cohort, whereas, in the setting of a summative assessment, both teaching formats appeared to be equally effective. A summative instead of a formative assessment doubled the performance increase (Cohen's d 4.9 versus 2.4), mitigating any difference between teaching formats. Within the second cohort, the significant difference between the two teaching formats was maintained in the retention test (p=0.017). However, in both cohorts, a significant decrease in student performance was detected during the 8 weeks following the cardiovascular course. Assessment format appeared to be more powerful than choice of instructional method in enhancing student learning. The effect observed in the second cohort was masked by an overriding incentive generated by the summative assessment in the first cohort. This masking effect should be considered in studies assessing the effectiveness of different teaching methods.

  15. Electrocardiogram signal quality measures for unsupervised telehealth environments

    International Nuclear Information System (INIS)

    Redmond, S J; Xie, Y; Chang, D; Lovell, N H; Basilakis, J

    2012-01-01

    The use of telehealth paradigms for the remote management of patients suffering from chronic conditions has become more commonplace with the advancement of Internet connectivity and enterprise software systems. To facilitate clinicians in managing large numbers of telehealth patients, and in digesting the vast array of data returned from the remote monitoring environment, decision support systems in various guises are often utilized. The success of decision support systems in interpreting patient conditions from physiological data is dependent largely on the quality of these recorded data. This paper outlines an algorithm to determine the quality of single-lead electrocardiogram (ECG) recordings obtained from telehealth patients. Three hundred short ECG recordings were manually annotated to identify movement artifact, QRS locations and signal quality (discrete quality levels) by a panel of three experts, who then reconciled the annotation as a group to resolve any discrepancies. After applying a published algorithm to remove gross movement artifact, the proposed method was then applied to estimate the remaining ECG signal quality, using a Parzen window supervised statistical classifier model. The three-class classifier model, using a number of time-domain features and evaluated using cross validation, gave an accuracy in classifying signal quality of 78.7% (κ = 0.67) when using fully automated preprocessing algorithms to remove gross motion artifact and detect QRS locations. This is a similar level of accuracy to the reported human inter-scorer agreement when generating the gold standard annotation (accuracy = 70–89.3%, κ = 0.54–0.84). These results indicate that the assessment of the quality of single-lead ECG recordings, acquired in unsupervised telehealth environments, is entirely feasible and may help to promote the acceptance and utility of future decision support systems for remotely managing chronic disease conditions. (paper)

  16. Proposed In-Training Electrocardiogram Interpretation Competencies for Undergraduate and Postgraduate Trainees.

    Science.gov (United States)

    Antiperovitch, Pavel; Zareba, Wojciech; Steinberg, Jonathan S; Bacharova, Ljuba; Tereshchenko, Larisa G; Farre, Jeronimo; Nikus, Kjell; Ikeda, Takanori; Baranchuk, Adrian

    2017-11-08

    Despite its importance in everyday clinical practice, the ability of physicians to interpret electrocardiograms (ECGs) is highly variable. ECG patterns are often misdiagnosed, and electrocardiographic emergencies are frequently missed, leading to adverse patient outcomes. Currently, many medical education programs lack an organized curriculum and competency assessment to ensure trainees master this essential skill. ECG patterns that were previously mentioned in literature were organized into groups from A to D based on their clinical importance and distributed among levels of training. Incremental versions of this organization were circulated among members of the International Society of Electrocardiology and the International Society of Holter and Noninvasive Electrocardiology until complete consensus was reached. We present reasonably attainable ECG interpretation competencies for undergraduate and postgraduate trainees. Previous literature suggests that methods of teaching ECG interpretation are less important and can be selected based on the available resources of each education program and student preference. The evidence clearly favors summative trainee evaluation methods, which would facilitate learning and ensure that appropriate competencies are acquired. Resources should be allocated to ensure that every trainee reaches their training milestones and should ensure that no electrocardiographic emergency (class A condition) is ever missed. We hope that these guidelines will inform medical education programs and encourage them to allocate sufficient resources and develop organized curricula. Assessments must be in place to ensure trainees acquire the level-appropriate ECG interpretation skills that are required for safe clinical practice. © 2017 Society of Hospital Medicine.

  17. Evaluation of agreement between temporal series obtained from electrocardiogram and pulse wave.

    Science.gov (United States)

    Leikan, GM; Rossi, E.; Sanz, MCuadra; Delisle Rodríguez, D.; Mántaras, MC; Nicolet, J.; Zapata, D.; Lapyckyj, I.; Siri, L. Nicola; Perrone, MS

    2016-04-01

    Heart rate variability allows to study the cardiovascular autonomic nervous system modulation. Usually, this signal is obtained from the electrocardiogram (ECG). A simpler method for recording the pulse wave (PW) is by means of finger photoplethysmography (PPG), which also provides information about the duration of the cardiac cycle. In this study, the correlation and agreement between the time series of the intervals between heartbeats obtained from the ECG with those obtained from the PPG, were studied. Signals analyzed were obtained from young, healthy and resting subjects. For statistical analysis, the Pearson correlation coefficient and the Bland and Altman limits of agreement were used. Results show that the time series constructed from the PW would not replace the ones obtained from ECG.

  18. Challenges of ECG monitoring and ECG interpretation in dialysis units.

    Science.gov (United States)

    Poulikakos, Dimitrios; Malik, Marek

    Patients on hemodialysis (HD) suffer from high cardiovascular morbidity and mortality due to high rates of coronary artery disease and arrhythmias. Electrocardiography (ECG) is often performed in the dialysis units as part of routine clinical assessment. However, fluid and electrolyte changes have been shown to affect all ECG morphologies and intervals. ECG interpretation thus depends on the time of the recording in relation to the HD session. In addition, arrhythmias during HD are common, and dialysis-related ECG artifacts mimicking arrhythmias have been reported. Studies using advanced ECG analyses have examined the impact of the HD procedure on selected repolarization descriptors and heart rate variability indices. Despite the challenges related to the impact of the fluctuant fluid and electrolyte status on conventional and advanced ECG parameters, further research in ECG monitoring during dialysis has the potential to provide clinically meaningful and practically useful information for diagnostic and risk stratification purposes. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

  19. Significance of electrocardiogram recording in high intercostal spaces in patients with early repolarization syndrome.

    Science.gov (United States)

    Kamakura, Tsukasa; Wada, Mitsuru; Nakajima, Ikutaro; Ishibashi, Kohei; Miyamoto, Koji; Okamura, Hideo; Noda, Takashi; Aiba, Takeshi; Takaki, Hiroshi; Yasuda, Satoshi; Ogawa, Hisao; Shimizu, Wataru; Makiyama, Takeru; Kimura, Takeshi; Kamakura, Shiro; Kusano, Kengo

    2016-02-14

    Published reports regarding inferolateral early repolarization (ER) syndrome (ERS) before 2013 possibly included patients with Brugada-pattern electrocardiogram (BrP-ECG) recorded only in the high intercostal spaces (HICS). We investigated the significance of HICS ECG recording in ERS patients. Fifty-six patients showing inferolateral ER in the standard ECG and spontaneous ventricular fibrillation (VF) not linked to structural heart disease underwent drug provocation tests by sodium channel blockade with right precordial ECG (V1-V3) recording in the 2nd-4th intercostal spaces. The prevalence and long-term outcome of ERS patients with and without BrP-ECG in HICS were investigated. After 18 patients showing type 1 BrP-ECG in the standard ECG were excluded, 38 patients (34 males, mean age; 40.4 ± 13.6 years) were classified into four groups [group A (n = 6;16%):patients with ER and type 1 BrP-ECG only in HICS, group B (n = 5;13%):ERS with non-type 1 BrP-ECG only in HICS, group C (n = 8;21%):ERS with non-type 1 BrP-ECG in the standard ECG, and group D (n = 19;50%):ERS only, spontaneously or after drug provocation test]. During follow-up of 110.0 ± 55.4 months, the rate of VF recurrence including electrical storm was significantly higher in groups A (4/6:67%), B (4/5:80%), and C (4/8:50%) compared with D (2/19:11%) (A, B, and C vs. D, P < 0.05). Approximately 30% of the patients with ERS who had been diagnosed with the previous criteria showed BrP-ECG only in HICS. Ventricular fibrillation mostly recurred in patients showing BrP-ECG in any precordial lead including HICS; these comprised 50% of the ERS cohort. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  20. Impact of the 12-lead electrocardiogram on ED evaluation and management.

    Science.gov (United States)

    Benner, John P; Borloz, Matthew P; Adams, Madeline; Brady, William J

    2007-10-01

    This study was conducted to assess the impact (diagnostic, therapeutic, and disposition) of the 12-lead electrocardiogram (ECG) on emergency department (ED) patient evaluation and management. This project was a prospective study of a convenience sample of 304 ED patients undergoing ECG analysis during their evaluation in the ED of a level 1 trauma center. The data collection for this study was divided into 4 parts. In part I, the treating physicians determined the specific reasons for ECG analysis; categories include complaint-based (eg, chest pain), syndrome-based (eg, overdose/poisoning), and system-based (eg, "requested by consult"). In part II, all treating physicians were surveyed before ECG interpretation regarding the future diagnostic, therapeutic, and disposition plans for the patient based only on history and physical examination. Their comments were recorded on a standardized data sheet. In part III, the physicians were surveyed after their interpretation of the ECG as to whether the results could suggest any further diagnostic information (eg, normal vs abnormal), or provide enough information for the patient care plan to be altered. In part IV of the study period, alterations to the original diagnostic, therapeutic, and disposition plans made by information provided by the ECG were obtained from the treating physician. A total of 304 patients underwent ECG examination and were used for data analysis. The average age of patients, of which 48% were men, was 60 years. The most common complaints that prompted electrocardiographic evaluation were chest pain and dyspnea. The most common reason an ECG was ordered was nursing staff protocol. Physicians determined that they were able to make a diagnosis based primarily on ECG in 33 (10.9%) cases. The total number of ECGs that were determined to be normal was 95 (31.3%), 7 (2.3%) of which allowed a rule-out diagnosis; 209 (68.7%) of total ECGs were determined to be abnormal, 72 (23.6%) of which were considered

  1. Removing movement artifacts from equine ECG recordings acquired with textile electrodes.

    Science.gov (United States)

    Lanata, Antonio; Guidi, Andrea; Baragli, Paolo; Paradiso, Rita; Valenza, Gaetano; Scilingo, Enzo Pasquale

    2015-01-01

    This study reports on the implementation of a novel system to detect and reduce movement artifact (MA) contribution in electrocardiogram (ECG) recordings acquired from horses in free movement conditions. The system comprises both integrated textile electrodes for ECG acquisition and one triaxial accelerometer for movement monitoring. Here, ECG and physical activity are continuously acquired from seven horses through the wearable system and a model that integrates cardiovascular and movement information to estimate the MA contribution is implemented. Moreover, in this study we propose a new algorithm where the Stationary Wavelet Transform (SWT) decomposition algorithm is employed to identify and remove movement artifacts from ECG recodigns. Achieved results showed a reduction of MA percentage greater than 40% between before- and after- the application of the proposed algorithm to seven hours of recordings.

  2. Wireless and Non-contact ECG Measurement System – the “Aachen SmartChair”

    Directory of Open Access Journals (Sweden)

    A. Aleksandrowicz

    2007-01-01

    Full Text Available This publication describes a measurement system that obtains an electrocardiogram (ECG by capacitively coupled electrodes. Fordemonstration purposes, this measurement system was integrated into an off-the-shelf office chair (so-called “Aachen SmartChair”.Whereas in usual clinical applications adhesive, conductively-coupled electrodes have to be attached to the skin, the described system is able to measure an ECG without direct skin contact through the cloth. A wireless communication module was integrated for transmitting theECG data to a PC or to an ICU patient monitor. For system validation, a classical ECG with conductive electrodes and an oxygensaturation signal (SpO2 were obtained simultaneously. Finally, system-specific problems of the presented device are discussed.

  3. A novel ECG data compression method based on adaptive Fourier decomposition

    Science.gov (United States)

    Tan, Chunyu; Zhang, Liming

    2017-12-01

    This paper presents a novel electrocardiogram (ECG) compression method based on adaptive Fourier decomposition (AFD). AFD is a newly developed signal decomposition approach, which can decompose a signal with fast convergence, and hence reconstruct ECG signals with high fidelity. Unlike most of the high performance algorithms, our method does not make use of any preprocessing operation before compression. Huffman coding is employed for further compression. Validated with 48 ECG recordings of MIT-BIH arrhythmia database, the proposed method achieves the compression ratio (CR) of 35.53 and the percentage root mean square difference (PRD) of 1.47% on average with N = 8 decomposition times and a robust PRD-CR relationship. The results demonstrate that the proposed method has a good performance compared with the state-of-the-art ECG compressors.

  4. Bedside identification of patients at risk for PVC-induced cardiomyopathy: Is ECG useful?

    Science.gov (United States)

    Garster, Noelle C; Henrikson, Charles A

    2017-07-01

    Premature ventricular complexes (PVCs) are an underrecognized cause of cardiomyopathy. Standard 12-lead electrocardiogram (ECG) has potential to direct attention toward at-risk patients. We performed a single-center, retrospective chart review of 1,240 patients who completed ECG and Holter monitoring at Oregon Health and Science University Hospital between January 1, 2011 and December 31, 2013 to investigate the relationship of PVC frequency on ECG with burden on Holter. Primary outcome measures included PVC quantity on ECG, mean PVC quantity on Holter, and percentage of total beats on Holter recorded as PVCs. High PVC burden was defined as ≥10% of total beats. Weighted mean percentages of total beats on Holter monitor recorded as PVCs were calculated for 0, 1, 2, and ≥3 PVCs on ECG and found to be 1.4% (n = 1,128), 3.5% (n = 32), 4.3% (n = 25), and 16.6% (n = 55), respectively, which represent statistically significant differences (P PVC Holter burden was 58%. Negative predictive value for 0 PVCs on ECG was 98%. The sensitivity and specificity of ECG to identify high PVC burden on Holter was 72% and 93.6%, respectively, when utilizing a positive ECG result as one PVC or more, and 44% and 98.9%, respectively, with ≥3 PVCs on ECG. The positive likelihood ratio corresponding to ≥3 PVCs on ECG was 40. These findings demonstrate that the number of PVCs on ECG can be utilized for quick bedside estimation of high PVC burden. © 2017 Wiley Periodicals, Inc.

  5. [Removal Algorithm of Power Line Interference in Electrocardiogram Based on Morphological Component Analysis and Ensemble Empirical Mode Decomposition].

    Science.gov (United States)

    Zhao, Wei; Xiao, Shixiao; Zhang, Baocan; Huang, Xiaojing; You, Rongyi

    2015-12-01

    Electrocardiogram (ECG) signals are susceptible to be disturbed by 50 Hz power line interference (PLI) in the process of acquisition and conversion. This paper, therefore, proposes a novel PLI removal algorithm based on morphological component analysis (MCA) and ensemble empirical mode decomposition (EEMD). Firstly, according to the morphological differences in ECG waveform characteristics, the noisy ECG signal was decomposed into the mutated component, the smooth component and the residual component by MCA. Secondly, intrinsic mode functions (IMF) of PLI was filtered. The noise suppression rate (NSR) and the signal distortion ratio (SDR) were used to evaluate the effect of de-noising algorithm. Finally, the ECG signals were re-constructed. Based on the experimental comparison, it was concluded that the proposed algorithm had better filtering functions than the improved Levkov algorithm, because it could not only effectively filter the PLI, but also have smaller SDR value.

  6. Portable ECG design and application based on wireless sensor network

    Directory of Open Access Journals (Sweden)

    Gül Fatma TÜRKER

    2016-05-01

    Full Text Available In this study, in order to follow the heart signals of patients that needs to be monitored instantly and continuously without mobility restrictions, a portable electrocardiogram circuit is designed. After performing the detection, upgrading, cleaning and digitizing of ECG signal received from patient via disposable electrodes, ECG signals was performed that transmit to a central node with Wireless Sensor Network (WSN based on ZigBee 802.11.4 standard. Central node is connected to the serial port of a computer. Received data from the central node is processed on computer and continuous flow graph is obtained. The obligation to use wires for tracing patients’ ECG has been removed with this portable system. As it can be seen in this study, thanks to WSN’s property of forming network by itself and its augmentable loop property, the restrain of ECG signals to reach far away distances can be surmounted. The transmission of biological signals with WSN will light on many studies that follow of patients from a distance.

  7. ECG-cryptography and authentication in body area networks.

    Science.gov (United States)

    Zhang, Zhaoyang; Wang, Honggang; Vasilakos, Athanasios V; Fang, Hua

    2012-11-01

    Wireless body area networks (BANs) have drawn much attention from research community and industry in recent years. Multimedia healthcare services provided by BANs can be available to anyone, anywhere, and anytime seamlessly. A critical issue in BANs is how to preserve the integrity and privacy of a person's medical data over wireless environments in a resource efficient manner. This paper presents a novel key agreement scheme that allows neighboring nodes in BANs to share a common key generated by electrocardiogram (ECG) signals. The improved Jules Sudan (IJS) algorithm is proposed to set up the key agreement for the message authentication. The proposed ECG-IJS key agreement can secure data communications over BANs in a plug-n-play manner without any key distribution overheads. Both the simulation and experimental results are presented, which demonstrate that the proposed ECG-IJS scheme can achieve better security performance in terms of serval performance metrics such as false acceptance rate (FAR) and false rejection rate (FRR) than other existing approaches. In addition, the power consumption analysis also shows that the proposed ECG-IJS scheme can achieve energy efficiency for BANs.

  8. An Interoperable System toward Cardiac Risk Stratification from ECG Monitoring

    Science.gov (United States)

    Mora-Jiménez, Inmaculada; Ramos-López, Javier; Quintanilla Fernández, Teresa; García-García, Antonio; Díez-Mazuela, Daniel; García-Alberola, Arcadi

    2018-01-01

    Many indices have been proposed for cardiovascular risk stratification from electrocardiogram signal processing, still with limited use in clinical practice. We created a system integrating the clinical definition of cardiac risk subdomains from ECGs and the use of diverse signal processing techniques. Three subdomains were defined from the joint analysis of the technical and clinical viewpoints. One subdomain was devoted to demographic and clinical data. The other two subdomains were intended to obtain widely defined risk indices from ECG monitoring: a simple-domain (heart rate turbulence (HRT)), and a complex-domain (heart rate variability (HRV)). Data provided by the three subdomains allowed for the generation of alerts with different intensity and nature, as well as for the grouping and scrutinization of patients according to the established processing and risk-thresholding criteria. The implemented system was tested by connecting data from real-world in-hospital electronic health records and ECG monitoring by considering standards for syntactic (HL7 messages) and semantic interoperability (archetypes based on CEN/ISO EN13606 and SNOMED-CT). The system was able to provide risk indices and to generate alerts in the health records to support decision-making. Overall, the system allows for the agile interaction of research and clinical practice in the Holter-ECG-based cardiac risk domain. PMID:29494497

  9. An Interoperable System toward Cardiac Risk Stratification from ECG Monitoring

    Directory of Open Access Journals (Sweden)

    Cristina Soguero-Ruiz

    2018-03-01

    Full Text Available Many indices have been proposed for cardiovascular risk stratification from electrocardiogram signal processing, still with limited use in clinical practice. We created a system integrating the clinical definition of cardiac risk subdomains from ECGs and the use of diverse signal processing techniques. Three subdomains were defined from the joint analysis of the technical and clinical viewpoints. One subdomain was devoted to demographic and clinical data. The other two subdomains were intended to obtain widely defined risk indices from ECG monitoring: a simple-domain (heart rate turbulence (HRT, and a complex-domain (heart rate variability (HRV. Data provided by the three subdomains allowed for the generation of alerts with different intensity and nature, as well as for the grouping and scrutinization of patients according to the established processing and risk-thresholding criteria. The implemented system was tested by connecting data from real-world in-hospital electronic health records and ECG monitoring by considering standards for syntactic (HL7 messages and semantic interoperability (archetypes based on CEN/ISO EN13606 and SNOMED-CT. The system was able to provide risk indices and to generate alerts in the health records to support decision-making. Overall, the system allows for the agile interaction of research and clinical practice in the Holter-ECG-based cardiac risk domain.

  10. Wearable Noncontact Armband for Mobile ECG Monitoring System.

    Science.gov (United States)

    Rachim, Vega Pradana; Chung, Wan-Young

    2016-12-01

    One of the best ways to obtain health information is from an electrocardiogram (ECG). Through an ECG, characteristics such as patients' heartbeats, heart conditions, and heart disease can be analyzed. Unfortunately, most available healthcare devices do not provide clinical data such as information regarding patients' heart activities. Many researchers have tried to solve this problem by inventing wearable heart monitoring systems with a chest strap or wristband, but their performances were not feasible for practical applications. Thus, the aim of this study is to build a new system to monitor heart activity through ECG signals. The proposed system consists of capacitive-coupled electrodes embedded in an armband. It is considered to be a reliable, robust, and low-power-transmission ECG monitoring system. The reliability of this system was achieved by the careful placement of sensors in the armband. Bluetooth low energy (BLE) was used as the protocol for data transmission; this protocol was proposed to develop the low-power-transmission system. For robustness, the proposed system is equipped with analysis capabilities-e.g., real-time heartbeat detection and a filter algorithm to ignore distractions from body movements or noise from the environment.

  11. A comprehensive performance analysis of EEMD-BLMS and DWT-NN hybrid algorithms for ECG denoising

    DEFF Research Database (Denmark)

    Kærgaard, Kevin; Jensen, Søren Hjøllund; Puthusserypady, Sadasivan

    2016-01-01

    Electrocardiogram (ECG) is a widely used non-invasive method to study the rhythmic activity of theheart. These signals, however, are often obscured by artifacts/noises from various sources and mini-mization of these artifacts is of paramount importance for detecting anomalies. This paper presents...

  12. Prediction of cardiac death : an epidemiological study on the prognostic significance of 24-hour ECG-recording

    NARCIS (Netherlands)

    J.P. Velema (Johan)

    1982-01-01

    textabstractSince the introduction of the string galvanometer by Einthoven (1901), various instruments have been developed (a technical review is given by Dunn & Rahm, 1950) to record the so-called electrocardiogram (ECG). Physical activity, changes in position and certain bodily functions such as

  13. Noninvasive extraction of fetal electrocardiogram based on Support Vector Machine

    Science.gov (United States)

    Fu, Yumei; Xiang, Shihan; Chen, Tianyi; Zhou, Ping; Huang, Weiyan

    2015-10-01

    The fetal electrocardiogram (FECG) signal has important clinical value for diagnosing the fetal heart diseases and choosing suitable therapeutics schemes to doctors. So, the noninvasive extraction of FECG from electrocardiogram (ECG) signals becomes a hot research point. A new method, the Support Vector Machine (SVM) is utilized for the extraction of FECG with limited size of data. Firstly, the theory of the SVM and the principle of the extraction based on the SVM are studied. Secondly, the transformation of maternal electrocardiogram (MECG) component in abdominal composite signal is verified to be nonlinear and fitted with the SVM. Then, the SVM is trained, and the training results are compared with the real data to ensure the effect of the training. Meanwhile, the parameters of the SVM are optimized to achieve the best performance so that the learning machine can be utilized to fit the unknown samples. Finally, the FECG is extracted by removing the optimal estimation of MECG component from the abdominal composite signal. In order to evaluate the performance of FECG extraction based on the SVM, the Signal-to-Noise Ratio (SNR) and the visual test are used. The experimental results show that the FECG with good quality can be extracted, its SNR ratio is significantly increased as high as 9.2349 dB and the time cost is significantly decreased as short as 0.802 seconds. Compared with the traditional method, the noninvasive extraction method based on the SVM has a simple realization, the shorter treatment time and the better extraction quality under the same conditions.

  14. Simple method for adaptive filtering of motion artifacts in E-textile wearable ECG sensors.

    Science.gov (United States)

    Alkhidir, Tamador; Sluzek, Andrzej; Yapici, Murat Kaya

    2015-08-01

    In this paper, we have developed a simple method for adaptive out-filtering of the motion artifact from the electrocardiogram (ECG) obtained by using conductive textile electrodes. The textile electrodes were placed on the left and the right wrist to measure ECG through lead-1 configuration. The motion artifact was induced by simple hand movements. The reference signal for adaptive filtering was obtained by placing additional electrodes at one hand to capture the motion of the hand. The adaptive filtering was compared to independent component analysis (ICA) algorithm. The signal-to-noise ratio (SNR) for the adaptive filtering approach was higher than independent component analysis in most cases.

  15. Accelerated free breathing ECG triggered contrast enhanced pulmonary vein magnetic resonance angiography using compressed sensing

    OpenAIRE

    Roujol, Sébastien; Foppa, Murilo; Basha, Tamer A; Akçakaya, Mehmet; Kissinger, Kraig V; Goddu, Beth; Berg, Sophie; Nezafat, Reza

    2014-01-01

    Background: To investigate the feasibility of accelerated electrocardiogram (ECG)-triggered contrast enhanced pulmonary vein magnetic resonance angiography (CE-PV MRA) with isotropic spatial resolution using compressed sensing (CS). Methods: Nineteen patients (59 ± 13 y, 11 M) referred for MR were scanned using the proposed accelerated free breathing ECG-triggered 3D CE-PV MRA sequence (FOV = 340 × 340 × 110 mm3, spatial resolution = 1.5 × 1.5 × 1.5 mm3, acquisition window = 140 ms at mid dia...

  16. The ability of an electrocardiogram to predict fatal and non-fatal cardiac events in asymptomatic middle-aged subjects.

    Science.gov (United States)

    Terho, Henri K; Tikkanen, Jani T; Kenttä, Tuomas V; Junttila, M Juhani; Aro, Aapo L; Anttonen, Olli; Kerola, Tuomas; Rissanen, Harri A; Knekt, Paul; Reunanen, Antti; Huikuri, Heikki V

    2016-11-01

    The long-term prognostic value of a standard 12-lead electrocardiogram (ECG) for predicting cardiac events in apparently healthy middle-aged subjects is not well defined. A total of 9511 middle-aged subjects (mean age 43 ± 8.2 years, 52% males) without a known cardiac disease and with a follow-up 40 years were included in the study. Fatal and non-fatal cardiac events were collected from the national registries. The predictive value of ECG was separately analyzed for 10 and 30 years. Major ECG abnormalities were classified according to the Minnesota code. Subjects with major ECG abnormalities (N = 1131) had an increased risk of cardiac death after 10-years (adjusted hazard ratio [HR] 1.7; 95% confidence interval [95% CI], 1.1-2.5, p = 0.009) and 30-years of follow-up (HR 1.3, 95% CI, 1.1-1.5, p electrocardiogram are shown to have prognostic significance for cardiac events in elderly subjects without known cardiac disease. Our results suggest that ECG abnormalities increase the risk of fatal cardiac events also in middle-aged healthy subjects.

  17. Prognostic value of an electrocardiogram at rest and exercise test in patients admitted with suspected acute myocardial infarction, in whom the diagnosis is not confirmed

    DEFF Research Database (Denmark)

    Madsen, J K; Hommel, E; Hansen, J F

    1987-01-01

    The prognosis following discharge in 217 patients admitted with suspected acute myocardial infarction (AMI) due to chest pain, but in whom AMI was not confirmed, was related to the electrocardiogram (ECG) at rest and a symptom-limited exercise test. The patients were followed for 12 to 24 months...

  18. Comparison of infarct size changes with delayed contrast-enhanced magnetic resonance imaging and electrocardiogram QRS scoring during the 6 months after acutely reperfused myocardial infarction

    DEFF Research Database (Denmark)

    Bang, L.E.; Ripa, R.S.; Grande, P.

    2008-01-01

    INTRODUCTION: Magnetic resonance imaging using the delayed contrast-enhanced (DE-MRI) method can be used for characterizing and quantifying myocardial infarction (MI). Electrocardiogram (ECG) score after the acute phase of MI can be used to estimate the portion of left ventricular myocardium...

  19. Screening of athletes: An electrocardiogram is not enough.

    Science.gov (United States)

    Skalik, R

    2015-05-01

    Professional and amateur athletic training can cause tremendous overload of the cardiovascular system and thus become a trigger of serious and often fatal cardiac events in athletes with a previously undetected underlying cardiovascular disease. Therefore, every athlete should undergo a specialized diagnostic and qualification screening before a training program is prescribed or continued. However, it is still an unresolved issue which of the accessible diagnostic tools should be routinely applied in order to increase the safety of extreme physical training and reduce the risk of sudden cardiac death. Pre-participation athlete evaluation including a standard electrocardiogram (ECG), physical examination, and familial history of cardiovascular diseases is important, but does not always guarantee high diagnostic accuracy. Hence, the aim of this review article is to discuss the controversy over the usefulness of ECG for the detection of cardiovascular diseases in athletes as well as the views on athlete screening methods in Europe and the USA. Differential diagnostic options and screening schemes are also described in particular groups of athletes in reference to their age, cardiovascular risk factors, as well as intensity and type of sport discipline.

  20. Assessing ECG signal quality indices to discriminate ECGs with artefacts from pathologically different arrhythmic ECGs.

    Science.gov (United States)

    Daluwatte, C; Johannesen, L; Galeotti, L; Vicente, J; Strauss, D G; Scully, C G

    2016-08-01

    False and non-actionable alarms in critical care can be reduced by developing algorithms which assess the trueness of an arrhythmia alarm from a bedside monitor. Computational approaches that automatically identify artefacts in ECG signals are an important branch of physiological signal processing which tries to address this issue. Signal quality indices (SQIs) derived considering differences between artefacts which occur in ECG signals and normal QRS morphology have the potential to discriminate pathologically different arrhythmic ECG segments as artefacts. Using ECG signals from the PhysioNet/Computing in Cardiology Challenge 2015 training set, we studied previously reported ECG SQIs in the scientific literature to differentiate ECG segments with artefacts from arrhythmic ECG segments. We found that the ability of SQIs to discriminate between ECG artefacts and arrhythmic ECG varies based on arrhythmia type since the pathology of each arrhythmic ECG waveform is different. Therefore, to reduce the risk of SQIs classifying arrhythmic events as noise it is important to validate and test SQIs with databases that include arrhythmias. Arrhythmia specific SQIs may also minimize the risk of misclassifying arrhythmic events as noise.

  1. Assessing ECG signal quality indices to discriminate ECGs with artefacts from pathologically different arrhythmic ECGs

    Science.gov (United States)

    Daluwatte, C; Johannesen, L; Galeotti, L; Vicente, J; Strauss, D G; Scully, C G

    2016-01-01

    False and non-actionable alarms in critical care can be reduced by developing algorithms which assess the trueness of an arrhythmia alarm from a bedside monitor. Computational approaches that automatically identify artefacts in ECG signals are an important branch of physiological signal processing which tries to address this issue. Signal quality indices (SQIs) derived considering differences between artefacts which occur in ECG signals and normal QRS morphology have the potential to discriminate pathologically different arrhythmic ECG segments as artefacts. Using ECG signals from the PhysioNet/Computing in Cardiology Challenge 2015 training set, we studied previously reported ECG SQIs in the scientific literature to differentiate ECG segments with artefacts from arrhythmic ECG segments. We found that the ability of SQIs to discriminate between ECG artefacts and arrhythmic ECG varies based on arrhythmia type since the pathology of each arrhythmic ECG waveform is different. Therefore, to reduce the risk of SQIs classifying arrhythmic events as noise it is important to validate and test SQIs with databases that include arrhythmias. Arrhythmia specific SQIs may also minimize the risk of misclassifying arrhythmic events as noise. PMID:27454007

  2. A low-power portable ECG sensor interface with dry electrodes

    International Nuclear Information System (INIS)

    Pu Xiaofei; Wan Lei; Zhang Hui; Qin Yajie; Hong Zhiliang

    2013-01-01

    This paper describes a low-power portable sensor interface dedicated to sensing and processing electrocardiogram (ECG) signals. Dry electrodes were employed in this ECG sensor, which eliminates the need of conductive gel and avoids complicated and mandatory skin preparation before electrode attachment. This ECG sensor system consists of two ICs, an analog front-end (AFE) and a successive approximation register analog-to-digital converter (SAR ADC) containing a relaxation oscillator. This proposed design was fabricated in a 0.18 μm 1P6M standard CMOS process. The AFE for extracting the biopotential signals is essential in this ECG sensor. In measurements, the AFE obtains a mid-band gain of 45 dB, a bandwidth from 0.6 to 160 Hz, and a total input referred noise of 2.8 μV rms while consuming 1 μW from the 1.8 V supply. The noise efficiency factor (NEF) of our design is 3.4. After conditioning, the amplified ECG signal is digitized by a 12-bit SAR ADC with 61.8 dB SNDR and 220 fJ/conversion-step. Finally, a complete ECG sensor interface with three dry copper electrodes is demonstrated in real-word setting, showing successful recordings of a capture ECG waveform. (semiconductor integrated circuits)

  3. A comprehensive survey of wearable and wireless ECG monitoring systems for older adults.

    Science.gov (United States)

    Baig, Mirza Mansoor; Gholamhosseini, Hamid; Connolly, Martin J

    2013-05-01

    Wearable health monitoring is an emerging technology for continuous monitoring of vital signs including the electrocardiogram (ECG). This signal is widely adopted to diagnose and assess major health risks and chronic cardiac diseases. This paper focuses on reviewing wearable ECG monitoring systems in the form of wireless, mobile and remote technologies related to older adults. Furthermore, the efficiency, user acceptability, strategies and recommendations on improving current ECG monitoring systems with an overview of the design and modelling are presented. In this paper, over 120 ECG monitoring systems were reviewed and classified into smart wearable, wireless, mobile ECG monitoring systems with related signal processing algorithms. The results of the review suggest that most research in wearable ECG monitoring systems focus on the older adults and this technology has been adopted in aged care facilitates. Moreover, it is shown that how mobile telemedicine systems have evolved and how advances in wearable wireless textile-based systems could ensure better quality of healthcare delivery. The main drawbacks of deployed ECG monitoring systems including imposed limitations on patients, short battery life, lack of user acceptability and medical professional's feedback, and lack of security and privacy of essential data have been also discussed.

  4. Biosignal integrated circuit with simultaneous acquisition of ECG and PPG for wearable healthcare applications.

    Science.gov (United States)

    Kim, Hyungseup; Park, Yunjong; Ko, Youngwoon; Mun, Yeongjin; Lee, Sangmin; Ko, Hyoungho

    2017-10-13

    Wearable healthcare systems require measurements from electrocardiograms (ECGs) and photoplethysmograms (PPGs), and the blood pressure of the user. The pulse transit time (PTT) can be calculated by measuring the ECG and PPG simultaneously. Continuous-time blood pressure without using an air cuff can be estimated by using the PTT. This paper presents a biosignal acquisition integrated circuit (IC) that can simultaneously measure the ECG and PPG for wearable healthcare applications. Included in this biosignal acquisition circuit are a voltage mode instrumentation amplifier (IA) for ECG acquisition and a current mode transimpedance amplifier for PPG acquisition. The analog outputs from the ECG and PPG channels are muxed and converted to digital signals using 12-bit successive approximation register (SAR) analog-to-digital converter (ADC). The proposed IC is fabricated by using a standard 0.18 μm CMOS process with an active area of 14.44 mm2. The total current consumption for the multichannel IC is 327 μA with a 3.3 V supply. The measured input referred noise of ECG readout channel is 1.3 μVRMS with a bandwidth of 0.5 Hz to 100 Hz. And the measured input referred current noise of the PPG readout channel is 0.122 nA/√Hz with a bandwidth of 0.5 Hz to 100 Hz. The proposed IC, which is implemented using various circuit techniques, can measure ECG and PPG signals simultaneously to calculate the PTT for wearable healthcare applications.

  5. New real-time heartbeat detection method using the angle of a single-lead electrocardiogram.

    Science.gov (United States)

    Song, Mi-Hye; Cho, Sung-Pil; Kim, Wonky; Lee, Kyoung-Joung

    2015-04-01

    This study presents a new real-time heartbeat detection algorithm using the geometric angle between two consecutive samples of single-lead electrocardiogram (ECG) signals. The angle was adopted as a new index representing the slope of ECG signal. The method consists of three steps: elimination of high-frequency noise, calculation of the angle of ECG signal, and detection of R-waves using a simple adaptive thresholding technique. The MIT-BIH arrhythmia database, QT database, European ST-T database, T-wave alternans database and synthesized ECG signals were used to evaluate the performance of the proposed algorithm and compare with the results of other methods suggested in literature. The proposed method shows a high detection rate-99.95% of the sensitivity, 99.95% of the positive predictivity, and 0.10% of the fail detection rate on the four databases. The result shows that the proposed method can yield better or comparable performance than other literature despite the relatively simple process. The proposed algorithm needs only a single-lead ECG, and involves a simple and quick calculation. Moreover, it does not require post-processing to enhance the detection. Thus, it can be effectively applied to various real-time healthcare and medical devices. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. The electrocardiogram signal of Seba's short-tailed bat, Carollia perspicillata.

    Science.gov (United States)

    Mihova, Diana; Hechavarría, Julio C

    2016-07-01

    A number of studies have successfully used electrocardiogram (ECG) signals to characterize complex physiological phenomena such as associative learning in bats. However, at present, no thorough characterization of the structure of ECG signals is available for these animals. The aim of the present study was to quantitatively characterize features of the ECG signals in the bat species Carollia perspicillata, a species that is commonly used in neuroethology studies. Our results show that the ECG signals of C. perspicillata follow the typical mammalian pattern, in that they are composed by a P wave, QRS complex and a T wave. Peak-to-peak amplitudes in the bats' ECG signals were larger in measuring configurations in which one of the electrodes was attached to the right thumb. In addition, large differences in the instantaneous heart rate (HR) distributions were observed between ketamine/xylazine anesthetized and awake bats. Ketamine/xylazine might target the neural circuits that control HR, therefore, instantaneous HR measurements should only be used as physiological marker in awake animals.

  7. The effectiveness of an education program on nurses' knowledge of electrocardiogram interpretation.

    Science.gov (United States)

    Zhang, Huajun; Hsu, Lily Lihwa

    2013-10-01

    The aim of the study was to evaluate the effectiveness of a continuing education program on nurses' knowledge of interpretation of 12-lead electrocardiograms (ECGs). The study used a quasi-experimental design. Fifty-two nurses, including 23 nurses working in an emergency department, 12 nurses working in a cardiology department and 17 nurses working in an intensive care unit (ICU) were recruited for the study. Two learning methods were used: a lecture-based education program and a self-learning handbook. The effectiveness of the methods was evaluated using a questionnaire containing questions in five domains. Data analysis showed that before training, nurses who worked in the cardiology department scored higher in basic ECG knowledge than those in the emergency department and ICU; test scores of nurses who had worked for 2-10 years were higher than else. The post-test total and domain scores at 2 weeks, and 4 months after the lecture-based learning and 1 month after a self-learning ECG handbook was presented were higher than the pretest scores. Prior to training, ECG knowledge differed with respect to the nurses' different demographic characteristics. The lecture-based education program and self-learning handbook material were effective in improving the nurses' ECG knowledge. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. A portable respiratory rate estimation system with a passive single-lead electrocardiogram acquisition module.

    Science.gov (United States)

    Nayan, Nazrul Anuar; Risman, Nur Sabrina; Jaafar, Rosmina

    2016-07-27

    Among vital signs of acutely ill hospital patients, respiratory rate (RR) is a highly accurate predictor of health deterioration. This study proposes a system that consists of a passive and non-invasive single-lead electrocardiogram (ECG) acquisition module and an ECG-derived respiratory (EDR) algorithm in the working prototype of a mobile application. Before estimating RR that produces the EDR rate, ECG signals were evaluated based on the signal quality index (SQI). The SQI algorithm was validated quantitatively using the PhysioNet/Computing in Cardiology Challenge 2011 training data set. The RR extraction algorithm was validated by adopting 40 MIT PhysioNet Multiparameter Intelligent Monitoring in Intensive Care II data set. The estimated RR showed a mean absolute error (MAE) of 1.4 compared with the ``gold standard'' RR. The proposed system was used to record 20 ECGs of healthy subjects and obtained the estimated RR with MAE of 0.7 bpm. Results indicate that the proposed hardware and algorithm could replace the manual counting method, uncomfortable nasal airflow sensor, chest band, and impedance pneumotachography often used in hospitals. The system also takes advantage of the prevalence of smartphone usage and increase the monitoring frequency of the current ECG of patients with critical illnesses.

  9. Reduction of Motion Artifacts and Improvement of R Peak Detecting Accuracy Using Adjacent Non-Intrusive ECG Sensors

    Directory of Open Access Journals (Sweden)

    Minho Choi

    2016-05-01

    Full Text Available Non-intrusive electrocardiogram (ECG monitoring has many advantages: easy to measure and apply in daily life. However, motion noise in the measured signal is the major problem of non-intrusive measurement. This paper proposes a method to reduce the noise and to detect the R peaks of ECG in a stable manner in a sitting arrangement using non-intrusive sensors. The method utilizes two capacitive ECG sensors (cECGs to measure ECG, and another two cECGs located adjacent to the sensors for ECG are added to obtain the information on motion. Then, active noise cancellation technique and the motion information are used to reduce motion noise. To verify the proposed method, ECG was measured indoors and during driving, and the accuracy of the detected R peaks was compared. After applying the method, the sum of sensitivity and positive predictivity increased 8.39% on average and 26.26% maximally in the data. Based on the results, it was confirmed that the motion noise was reduced and that more reliable R peak positions could be obtained by the proposed method. The robustness of the new ECG measurement method will elicit benefits to various health care systems that require noninvasive heart rate or heart rate variability measurements.

  10. ECG signal performance de-noising assessment based on threshold tuning of dual-tree wavelet transform.

    Science.gov (United States)

    El B'charri, Oussama; Latif, Rachid; Elmansouri, Khalifa; Abenaou, Abdenbi; Jenkal, Wissam

    2017-02-07

    Since the electrocardiogram (ECG) signal has a low frequency and a weak amplitude, it is sensitive to miscellaneous mixed noises, which may reduce the diagnostic accuracy and hinder the physician's correct decision on patients. The dual tree wavelet transform (DT-WT) is one of the most recent enhanced versions of discrete wavelet transform. However, threshold tuning on this method for noise removal from ECG signal has not been investigated yet. In this work, we shall provide a comprehensive study on the impact of the choice of threshold algorithm, threshold value, and the appropriate wavelet decomposition level to evaluate the ECG signal de-noising performance. A set of simulations is performed on both synthetic and real ECG signals to achieve the promised results. First, the synthetic ECG signal is used to observe the algorithm response. The evaluation results of synthetic ECG signal corrupted by various types of noise has showed that the modified unified threshold and wavelet hyperbolic threshold de-noising method is better in realistic and colored noises. The tuned threshold is then used on real ECG signals from the MIT-BIH database. The results has shown that the proposed method achieves higher performance than the ordinary dual tree wavelet transform into all kinds of noise removal from ECG signal. The simulation results indicate that the algorithm is robust for all kinds of noises with varying degrees of input noise, providing a high quality clean signal. Moreover, the algorithm is quite simple and can be used in real time ECG monitoring.

  11. A Smart Shirt Made with Conductive Ink and Conductive Foam for the Measurement of Electrocardiogram Signals with Unipolar Precordial Leads

    Directory of Open Access Journals (Sweden)

    Yasunori Tada

    2015-11-01

    Full Text Available The Holter monitor is used to measure an electrocardiogram (ECG signal while a subject moves. However, the Holter monitor is uncomfortable for the subject. Another method of measuring the ECG signal uses a smart shirt. We developed a smart shirt that has six electrodes on the chest and can measure a detailed ECG, obtained with unipolar precordial leads. The electrodes and wires of the shirt are made of conductive ink that is flexible and stretchable. The smart shirt is stretchable and fits the body well. However, because of the gap between the smart shirt and the body, electrodes V1 and V2 do not touch the body consistently. We developed a conductive foam block that fills this gap. We investigated the characteristics of the conductive foam block, and measured ECG signals using the smart shirt. The electrical resistance of the conductive foam block was reduced by pressure. This characteristic could be utilized to measure the ECG signal because the block was pressed by the body and smart shirt. We could measure the ECG signal using the smart shirt and blocks while the subject walked and could detect peaks of the ECG signal while the subject jogged slowly.

  12. Development of electrocardiogram intervals during growth of FVB/N neonate mice

    Science.gov (United States)

    2010-01-01

    Background Electrocardiography remains the best diagnostic tool and therapeutic biomarker for a spectrum of pediatric diseases involving cardiac or autonomic nervous system defects. As genetic links to these disorders are established and transgenic mouse models produced in efforts to understand and treat them, there is a surprising lack of information on electrocardiograms (ECGs) and ECG abnormalities in neonate mice. This is likely due to the trauma and anaesthesia required of many legacy approaches to ECG recording in mice, exacerbated by the fragility of many mutant neonates. Here, we use a non-invasive system to characterize development of the heart rate and electrocardiogram throughout the growth of conscious neonate FVB/N mice. Results We examine ECG waveforms as early as two days after birth. At this point males and females demonstrate comparable heart rates that are 50% lower than adult mice. Neonatal mice exhibit very low heart rate variability. Within 12 days of birth PR, QRS and QTc interval durations are near adult values while heart rate continues to increase until weaning. Upon weaning FVB/N females quickly develop slower heart rates than males, though PR intervals are comparable between sexes until a later age. This suggests separate developmental events may contribute to these gender differences in electrocardiography. Conclusions We provide insight with a new level of detail to the natural course of heart rate establishment in neonate mice. ECG can now be conveniently and repeatedly used in neonatal mice. This should serve to be of broad utility, facilitating further investigations into development of a diverse group of diseases and therapeutics in preclinical mouse studies. PMID:20735846

  13. Differentiating Obstructive from Central and Complex Sleep Apnea Using an Automated Electrocardiogram-Based Method

    Science.gov (United States)

    Thomas, Robert Joseph; Mietus, Joseph E.; Peng, Chung-Kang; Gilmartin, Geoffrey; Daly, Robert W.; Goldberger, Ary L.; Gottlieb, Daniel J.

    2007-01-01

    Study Objectives: Complex sleep apnea is defined as sleep disordered breathing secondary to simultaneous upper airway obstruction and respiratory control dysfunction. The objective of this study was to assess the utility of an electrocardiogram (ECG)-based cardiopulmonary coupling technique to distinguish obstructive from central or complex sleep apnea. Design: Analysis of archived polysomnographic datasets. Setting: A laboratory for computational signal analysis. Interventions: None. Measurements and Results: The PhysioNet Sleep Apnea Database, consisting of 70 polysomnograms including single-lead ECG signals of approximately 8 hours duration, was used to train an ECG-based measure of autonomic and respiratory interactions (cardiopulmonary coupling) to detect periods of apnea and hypopnea, based on the presence of elevated low-frequency coupling (e-LFC). In the PhysioNet BIDMC Congestive Heart Failure Database (ECGs of 15 subjects), a pattern of “narrow spectral band” e-LFC was especially common. The algorithm was then applied to the Sleep Heart Health Study–I dataset, to select the 15 records with the highest amounts of broad and narrow spectral band e-LFC. The latter spectral characteristic seemed to detect not only periods of central apnea, but also obstructive hypopneas with a periodic breathing pattern. Applying the algorithm to 77 sleep laboratory split-night studies showed that the presence of narrow band e-LFC predicted an increased sensitivity to induction of central apneas by positive airway pressure. Conclusions: ECG-based spectral analysis allows automated, operator-independent characterization of probable interactions between respiratory dyscontrol and upper airway anatomical obstruction. The clinical utility of spectrographic phenotyping, especially in predicting failure of positive airway pressure therapy, remains to be more thoroughly tested. Citation: Thomas RJ; Mietus JE; Peng CK; Gilmartin G; Daly RW; Goldberger AL; Gottlieb DJ

  14. The electrocardiogram of anaesthetized southern sea lion (Otaria flavescens) females.

    Science.gov (United States)

    Dassis, M; Rodríguez, D H; Rodríguez, E; Ponce de León, A; Castro, E

    2016-03-01

    The goal of this study was to characterize for the first time the electrocardiogram (ECG) of the southern sea lion (SSL) Otaria flavescens. Thirteen wild SSL females were captured at Isla de Lobos (Uruguay) and anaesthetized with isoflurane. Electrocardiographic recording was performed on anaesthetized animals at ventral recumbence following standardized procedures. The ECG recordings showed normal sinus rhythm. Amplitude and duration of P and T waves, QRS complex, PR interval, QT interval and ST segment (STS) were determined for all animals in all leads. QT corrected was determined in lead II. P wave polarity was consistent among animals (positive in LI, LII, LIII and AVF leads and negative in AVL and AVR leads for all animals), but T wave polarity did not present any constant pattern among animals, being either positive, negative or biphasic in different leads and different animals. The PR interval (0.15 ± 0.2 s) was similar to the allometric prediction for most of mammalian species including humans. The STS were normal in 10 of the SSL but showed STS depression in three of the animals. Almost all animals had a negative electrical axis (-30° to -120°), with one exception that showed a positive electrical axis (120°). Mean eupnoeic heart rate was 104.61 ± 10.06 (range = 88-120) beats per minute. This study was the first ECG description for this species, and provides valuable information for cardiac monitoring during anaesthesia. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Hyperkalemia on ECG

    Directory of Open Access Journals (Sweden)

    Bryson Hicks

    2016-09-01

    Full Text Available History of present illness: A 34-year-old diabetic female presented to the emergency department with chest pain status-post AICD firing. She described the pain as a “12 out of 10” which woke her from sleep at 0200, one hour prior to arrival. Vitals were unremarkable. She had no known history of renal failure. Due to frequent ED visits for chronic pain, patient had difficult vascular access and nursing was initially unable to obtain IV access. An abnormal rhythm was noted on the cardiac monitor, and ECG was ordered. Significant findings: Initial ECG shows tall, peaked T waves, most prominently in V3 and V4, as well as QRS widening. These findings are consistent with hyperkalemia, which was promptly treated. Follow-up ECG post-treatment shows narrowing of the QRS complexes and normalization of peaked T waves. Discussion: The etiology of hyperkalemia may be due to an acute insult such as crush injury, drug side effect, or in acute renal failure, but may also occur in the setting of a chronic insult such as chronic kidney disease.1 As potassium rises, several abnormalities can be identified on ECG. Initially the T waves become peaked and the QRS complexes widen.2,3 This can devolve into a wide complex rhythm, ventricular tachycardia, ventricular fibrillation, or asystole. Patients may also experience systemic symptoms such as weakness or paralysis.1 In this particular case, labs showed a potassium of 7.6-mmol/L after initial treatment (see repeat EKG. While the incidence of hyperkalemia in the general population is not defined, the incidence in hospitalized patients is 1.3-10%.4-8 Impaired kidney function is the most common risk factor found in 33-83% of affected patients.4,5,8,9 Treatment for hyperkalemia generally includes IV insulin and IV dextrose and nebulized albuterol for intracellular shift of potassium, IV furosemide and IV fluids for dilution and renal excretion of furosemide, and IV calcium for stabilization of cardiac membranes.2,3

  16. Prevalence and prognostic significance of ECG abnormalities in HIV-infected patients: results from the Strategies for Management of Antiretroviral Therapy study

    DEFF Research Database (Denmark)

    Soliman, Elsayed Z; Prineas, Ronald J; Roediger, Mollie P

    2011-01-01

    BACKGROUND: It remains debated whether to include resting electrocardiogram (ECG) in the routine care of human immunodeficiency virus (HIV)-infected patients. METHODS: This analysis included 4518 HIV-infected patients (28% women and 29% blacks) from the Strategies for Management of Antiretroviral...... Therapy study, a clinical trial aimed to compare 2 HIV treatment strategies. ECG abnormalities were classified using the Minnesota Code. Cox proportional hazards analysis was used to examine the association between baseline ECG abnormalities and incident cardiovascular disease (CVD). RESULTS: More than...... half of the participants (n = 2325, or 51.5%) had either minor or major ECG abnormalities. Minor ECG abnormalities (48.6%) were more common than major ECG abnormalities (7.7%). During a median follow-up of 28.7 months, 155 participants (3.4%) developed incident CVD. After adjusting for the study...

  17. New micro waveforms firstly recorded on electrocardiogram in human.

    Science.gov (United States)

    Liu, Renguang; Chang, Qinghua; Chen, Juan

    2015-10-01

    In our study, not only the P-QRS-T waves but also the micro-wavelets before QRS complex (in P wave and PR segment) and after QRS complex (ST segment and upstroke of T wave) were first to be identified on surface electrocardiogram in human by the "new electrocardiogram" machine (model PHS-A10) according to conventional 12-lead electrocardiogram connection methods. By comparison to the conventional electrocardiogram in 100 cases of healthy individuals and several patients with arrhythmias, we have found that the wavelets before P wave theoretically reflected electrical activity of sinus node and the micro-wavelets before QRS complex may be related to atrioventricular conduction system (atrioventricular node, His bundle and bundle branch) potentials. Noninvasive atrioventricular node and His bundle potential tracing will contribute to differentiation of the origin of wide QRS and the location of the atrioventricular block. We also have found that the wavelets after QRS complex may be associated with phase 2 and 3 repolarization of ventricular action potential, which will further reveal ventricular repolarization changes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Signal quality indices and data fusion for determining clinical acceptability of electrocardiograms

    International Nuclear Information System (INIS)

    Clifford, G D; Behar, J; Li, Q; Rezek, I

    2012-01-01

    A completely automated algorithm to detect poor-quality electrocardiograms (ECGs) is described. The algorithm is based on both novel and previously published signal quality metrics, originally designed for intensive care monitoring. The algorithms have been adapted for use on short (5–10 s) single- and multi-lead ECGs. The metrics quantify spectral energy distribution, higher order moments and inter-channel and inter-algorithm agreement. Seven metrics were calculated for each channel (84 features in all) and presented to either a multi-layer perceptron artificial neural network or a support vector machine (SVM) for training on a multiple-annotator labelled and adjudicated training dataset. A single-lead version of the algorithm was also developed in a similar manner. Data were drawn from the PhysioNet Challenge 2011 dataset where binary labels were available, on 1500 12-lead ECGs indicating whether the entire recording was acceptable or unacceptable for clinical interpretation. We re-annotated all the leads in both the training set (1000 labelled ECGs) and test dataset (500 12-lead ECGs where labels were not publicly available) using two independent annotators, and a third for adjudication of differences. We found that low-quality data accounted for only 16% of the ECG leads. To balance the classes (between high and low quality), we created extra noisy data samples by adding noise from PhysioNet’s noise stress test database to some of the clean 12-lead ECGs. No data were shared between training and test sets. A classification accuracy of 98% on the training data and 97% on the test data were achieved. Upon inspection, incorrectly classified data were found to be borderline cases which could be classified either way. If these cases were more consistently labelled, we expect our approach to achieve an accuracy closer to 100%. (paper)

  19. Interpretation of electrocardiogram images sent through the mobile phone multimedia messaging service.

    Science.gov (United States)

    Bilgi, Muhammet; Gülalp, Betül; Erol, Tansel; Güllü, Hakan; Karagün, Özlem; Altay, Hakan; Müderrisoğlu, Haldun

    2012-03-01

    In this study, the diagnostic accuracy of interpretations of electrocardiogram (ECG) images taken by a mobile phone and sent as multimedia message was investigated. The ECGs of 305 patients who were admitted to the emergency department with cardiac complaints were photographed with the camera of a Nokia (Espoo, Finland) N93 mobile phone. The images were sent via a multimedia messaging system to an identical mobile phone carried by a cardiologist and were interpreted on the screen of that mobile phone. Another cardiologist and an emergency physician interpreted ECG paper printouts separately. The findings of the core laboratory were used as the gold standard. The interpretation errors were scaled from 1 to 4 with respect to the significance of findings. The total ratio of Grade 4 errors, which consisted of significant errors, did not show any significant difference (p=0.76) between the interpretations by the emergency medicine specialist and the cardiologist who interpreted the ECGs on the mobile phone; the cardiologist who interpreted the ECG paper printouts made significantly fewer mistakes than the other two specialists (p=0.025 and p=0.023, respectively). The separate assessment of the findings showed that in the diagnostic process of ST-segment elevation, depression, and supraventricular tachycardia, the consistency of the interpretations (κ=0.81, κ=0.81, and κ=1.0, respectively) made on the mobile phone screen was slightly better than that of the emergency medicine specialist (κ=0.73, κ=0.77, and κ=0.80, respectively) and was similar to that of the cardiologist (κ=0.91, κ=0.91, and κ=1.0, respectively) who interpreted ECG paper printouts. Our findings suggest that sending the ECG images via a multimedia message service may be a practical and inexpensive telecardiology procedure.

  20. Short ECG segments predict defibrillation outcome using quantitative waveform measures.

    Science.gov (United States)

    Coult, Jason; Sherman, Lawrence; Kwok, Heemun; Blackwood, Jennifer; Kudenchuk, Peter J; Rea, Thomas D

    2016-12-01

    Quantitative waveform measures of the ventricular fibrillation (VF) electrocardiogram (ECG) predict defibrillation outcome. Calculation requires an ECG epoch without chest compression artifact. However, pauses in CPR can adversely affect survival. Thus the potential use of waveform measures is limited by the need to pause CPR. We sought to characterize the relationship between the length of the CPR-free epoch and the ability to predict outcome. We conducted a retrospective investigation using the CPR-free ECG prior to first shock among out-of-hospital VF cardiac arrest patients in a large metropolitan region (n=442). Amplitude Spectrum Area (AMSA) and Median Slope (MS) were calculated using ECG epochs ranging from 5s to 0.2s. The relative ability of the measures to predict return of organized rhythm (ROR) and neurologically-intact survival was evaluated at different epoch lengths by calculating the area under the receiver operating characteristic curve (AUC) using the 5-s epoch as the referent group. Compared to the 5-s epoch, AMSA performance declined significantly only after reducing epoch length to 0.2s for ROR (AUC 0.77-0.74, p=0.03) and with epochs of ≤0.6s for neurologically-intact survival (AUC 0.72-0.70, p=0.04). MS performance declined significantly with epochs of ≤0.8s for ROR (AUC 0.78-0.77, p=0.04) and with epochs ≤1.6s for neurologically-intact survival (AUC 0.72-0.71, p=0.04). Waveform measures predict defibrillation outcome using very brief ECG epochs, a quality that may enable their use in current resuscitation algorithms designed to limit CPR interruption. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. ABNORMALITY DETECTION IN ECG USING ARTIFICIAL NEURAL NETWORKS

    Directory of Open Access Journals (Sweden)

    Shahanaz Ayub

    2010-01-01

    Full Text Available Electrocardiogram represents electrical activity of the heart. Arrhythmias are among the most common ECG abnormalities. Millions of ECGs are taken for the diagnosis of various classes of patients, where ECG can provide a lot of information regarding the abnormality in the concerned patient, ECGs are analysed by the physicians and interpreted depending upon their experience.The interpretation may vary by physician to physician. Hence this work is all about the automation and consistency in the analysis of the ECG signals so that they must be diagnosed and interpreted accurately irrespective of the physicians. This would help to start an early treatment for the problems and many lives could be saved. Many works have been done previously but this paper presents a new concept by application of MATLAB based tools in the same weighted neural network algorithms. This will help to reduce the hardware requirements, make network more reliable and thus a hope to make it feasible. To do so various networks were designed using the MATLAB based tools (licensed version and parameters. Two classes of networks were designed, but with different training algorithms, namely Perceptron and Back propagation. They were provided training inputs from the data obtained from the standard MIT-BIH Arrhythmia database. After training different forms of networks, they were tested by providing unknown inputs as patient data and the results in the whole process from training to testing were recorded in the form of tables. The results for the normal beats were best in the case of Cascade-Forward Back propagation network algorithm. The percentage of correct classification is 100%.The results are compared with the previous work which concludes that the method proposed in this paper gives best results.

  2. WAVELET ANALYSIS OF ABNORMAL ECGS

    Directory of Open Access Journals (Sweden)

    Vasudha Nannaparaju

    2014-02-01

    Full Text Available Detection of the warning signals by the heart can be diagnosed from ECG. An accurate and reliable diagnosis of ECG is very important however which is cumbersome and at times ambiguous in time domain due to the presence of noise. Study of ECG in wavelet domain using both continuous Wavelet transform (CWT and discrete Wavelet transform (DWT, with well known wavelet as well as a wavelet proposed by the authors for this investigation is found to be useful and yields fairly reliable results. In this study, Wavelet analysis of ECGs of Normal, Hypertensive, Diabetic and Cardiac are carried out. The salient feature of the study is that detection of P and T phases in wavelet domain is feasible which are otherwise feeble or absent in raw ECGs.

  3. Deep Learning for ECG Classification

    Science.gov (United States)

    Pyakillya, B.; Kazachenko, N.; Mikhailovsky, N.

    2017-10-01

    The importance of ECG classification is very high now due to many current medical applications where this problem can be stated. Currently, there are many machine learning (ML) solutions which can be used for analyzing and classifying ECG data. However, the main disadvantages of these ML results is use of heuristic hand-crafted or engineered features with shallow feature learning architectures. The problem relies in the possibility not to find most appropriate features which will give high classification accuracy in this ECG problem. One of the proposing solution is to use deep learning architectures where first layers of convolutional neurons behave as feature extractors and in the end some fully-connected (FCN) layers are used for making final decision about ECG classes. In this work the deep learning architecture with 1D convolutional layers and FCN layers for ECG classification is presented and some classification results are showed.

  4. Computerized electrocardiogram in agoutis (Dasyprocta prymnolopha Wagler, 1831 anesthetized with ketamine and midazolam

    Directory of Open Access Journals (Sweden)

    Anaemilia N. Diniz

    Full Text Available ABSTRACT: An electrocardiogram is a test that assesses heart electrical activity and is applied more frequently in the veterinary care of wild animals. The present study aimed to define the electrocardiogram pattern of agoutis (Dasyprocta prymnolopha Wagler, 1831 anesthetized with ketamine and midazolam. Eighteen clinically healthy agoutis (D. prymnolopha were used from the Nucleus for Wild Animal Studies and Conservation (NEPAS of the Federal University of Piauí, Brazil. The animals were chemically restrained with 5% ketamine hydrochloride at a dose of 15mg/kg and midazolam at a dose of 1mg/kg by intramuscular injection. Electrocardiogram tests were carried out by a computerized method with the veterinary electrocardiogram [Acquisition Model for Computer (ECG - PC version Windows 95 Brazilian Electronic Technology (TEB consisting of an electronic circuit externally connected to a notebook computer with ECGPC-VET (TEB software installed on the hard disc. In analysing the EKG results, significant differences were observed for QRS complex duration, PR and QT intervals and for R wave millivoltage between the genders; but we observed a significant influence of weight despite the gender. In the present experiment, the anaesthetic protocol was shown to be well tolerated by the agoutis, and no arrhythmias occurred during the time the animals were monitored. The reference values obtained should be used to better understand the cardiac electrophysiology of the species and for its clinical and surgical management.

  5. An Integrated Approach Using Chaotic Map & Sample Value Difference Method for Electrocardiogram Steganography and OFDM Based Secured Patient Information Transmission.

    Science.gov (United States)

    Pandey, Anukul; Saini, Barjinder Singh; Singh, Butta; Sood, Neetu

    2017-10-18

    This paper presents a patient's confidential data hiding scheme in electrocardiogram (ECG) signal and its subsequent wireless transmission. Patient's confidential data is embedded in ECG (called stego-ECG) using chaotic map and the sample value difference approach. The sample value difference approach effectually hides the patient's confidential data in ECG sample pairs at the predefined locations. The chaotic map generates these predefined locations through the use of selective control parameters. Subsequently, the wireless transmission of the stego-ECG is analyzed using the Orthogonal Frequency Division Multiplexing (OFDM) system in a Rayleigh fading scenario for telemedicine applications. Evaluation of proposed method on all 48 records of MIT-BIH arrhythmia ECG database demonstrates that the embedding does not alter the diagnostic features of cover ECG. The secret data imperceptibility in stego-ECG is evident through the statistical and clinical performance measures. Statistical measures comprise of Percentage Root-mean-square Difference (PRD), Peak Signal to Noise Ratio (PSNR), and Kulback-Leibler Divergence (KL-Div), etc. while clinical metrics includes wavelet Energy Based Diagnostic Distortion (WEDD) and Wavelet based Weighted PRD (WWPRD). The various channel Signal-to-Noise Ratio scenarios are simulated for wireless communication of stego-ECG in OFDM system. The proposed method over all the 48 records of MIT-BIH arrhythmia database resulted in average, PRD = 0.26, PSNR = 55.49, KL-Div = 3.34 × 10 -6 , WEDD = 0.02, and WWPRD = 0.10 with secret data size of 21Kb. Further, a comparative analysis of proposed method and recent existing works was also performed. The results clearly, demonstrated the superiority of proposed method.

  6. Real-Time Patient-Specific ECG Classification by 1-D Convolutional Neural Networks.

    Science.gov (United States)

    Kiranyaz, Serkan; Ince, Turker; Gabbouj, Moncef

    2016-03-01

    This paper presents a fast and accurate patient-specific electrocardiogram (ECG) classification and monitoring system. An adaptive implementation of 1-D convolutional neural networks (CNNs) is inherently used to fuse the two major blocks of the ECG classification into a single learning body: feature extraction and classification. Therefore, for each patient, an individual and simple CNN will be trained by using relatively small common and patient-specific training data, and thus, such patient-specific feature extraction ability can further improve the classification performance. Since this also negates the necessity to extract hand-crafted manual features, once a dedicated CNN is trained for a particular patient, it can solely be used to classify possibly long ECG data stream in a fast and accurate manner or alternatively, such a solution can conveniently be used for real-time ECG monitoring and early alert system on a light-weight wearable device. The results over the MIT-BIH arrhythmia benchmark database demonstrate that the proposed solution achieves a superior classification performance than most of the state-of-the-art methods for the detection of ventricular ectopic beats and supraventricular ectopic beats. Besides the speed and computational efficiency achieved, once a dedicated CNN is trained for an individual patient, it can solely be used to classify his/her long ECG records such as Holter registers in a fast and accurate manner. Due to its simple and parameter invariant nature, the proposed system is highly generic, and, thus, applicable to any ECG dataset.

  7. Genetic algorithm for the optimization of features and neural networks in ECG signals classification.

    Science.gov (United States)

    Li, Hongqiang; Yuan, Danyang; Ma, Xiangdong; Cui, Dianyin; Cao, Lu

    2017-01-31

    Feature extraction and classification of electrocardiogram (ECG) signals are necessary for the automatic diagnosis of cardiac diseases. In this study, a novel method based on genetic algorithm-back propagation neural network (GA-BPNN) for classifying ECG signals with feature extraction using wavelet packet decomposition (WPD) is proposed. WPD combined with the statistical method is utilized to extract the effective features of ECG signals. The statistical features of the wavelet packet coefficients are calculated as the feature sets. GA is employed to decrease the dimensions of the feature sets and to optimize the weights and biases of the back propagation neural network (BPNN). Thereafter, the optimized BPNN classifier is applied to classify six types of ECG signals. In addition, an experimental platform is constructed for ECG signal acquisition to supply the ECG data for verifying the effectiveness of the proposed method. The GA-BPNN method with the MIT-BIH arrhythmia database achieved a dimension reduction of nearly 50% and produced good classification results with an accuracy of 97.78%. The experimental results based on the established acquisition platform indicated that the GA-BPNN method achieved a high classification accuracy of 99.33% and could be efficiently applied in the automatic identification of cardiac arrhythmias.

  8. Development of a portable Linux-based ECG measurement and monitoring system.

    Science.gov (United States)

    Tan, Tan-Hsu; Chang, Ching-Su; Huang, Yung-Fa; Chen, Yung-Fu; Lee, Cheng

    2011-08-01

    This work presents a portable Linux-based electrocardiogram (ECG) signals measurement and monitoring system. The proposed system consists of an ECG front end and an embedded Linux platform (ELP). The ECG front end digitizes 12-lead ECG signals acquired from electrodes and then delivers them to the ELP via a universal serial bus (USB) interface for storage, signal processing, and graphic display. The proposed system can be installed anywhere (e.g., offices, homes, healthcare centers and ambulances) to allow people to self-monitor their health conditions at any time. The proposed system also enables remote diagnosis via Internet. Additionally, the system has a 7-in. interactive TFT-LCD touch screen that enables users to execute various functions, such as scaling a single-lead or multiple-lead ECG waveforms. The effectiveness of the proposed system was verified by using a commercial 12-lead ECG signal simulator and in vivo experiments. In addition to its portability, the proposed system is license-free as Linux, an open-source code, is utilized during software development. The cost-effectiveness of the system significantly enhances its practical application for personal healthcare.

  9. Research of fetal ECG extraction using wavelet analysis and adaptive filtering.

    Science.gov (United States)

    Wu, Shuicai; Shen, Yanni; Zhou, Zhuhuang; Lin, Lan; Zeng, Yanjun; Gao, Xiaofeng

    2013-10-01

    Extracting clean fetal electrocardiogram (ECG) signals is very important in fetal monitoring. In this paper, we proposed a new method for fetal ECG extraction based on wavelet analysis, the least mean square (LMS) adaptive filtering algorithm, and the spatially selective noise filtration (SSNF) algorithm. First, abdominal signals and thoracic signals were processed by stationary wavelet transform (SWT), and the wavelet coefficients at each scale were obtained. For each scale, the detail coefficients were processed by the LMS algorithm. The coefficient of the abdominal signal was taken as the original input of the LMS adaptive filtering system, and the coefficient of the thoracic signal as the reference input. Then, correlations of the processed wavelet coefficients were computed. The threshold was set and noise components were removed with the SSNF algorithm. Finally, the processed wavelet coefficients were reconstructed by inverse SWT to obtain fetal ECG. Twenty cases of simulated data and 12 cases of clinical data were used. Experimental results showed that the proposed method outperforms the LMS algorithm: (1) it shows improvement in case of superposition R-peaks of fetal ECG and maternal ECG; (2) noise disturbance is eliminated by incorporating the SSNF algorithm and the extracted waveform is more stable; and (3) the performance is proven quantitatively by SNR calculation. The results indicated that the proposed algorithm can be used for extracting fetal ECG from abdominal signals. © 2013 Elsevier Ltd. All rights reserved.

  10. Self-organized neural network for the quality control of 12-lead ECG signals.

    Science.gov (United States)

    Chen, Yun; Yang, Hui

    2012-09-01

    Telemedicine is very important for the timely delivery of health care to cardiovascular patients, especially those who live in the rural areas of developing countries. However, there are a number of uncertainty factors inherent to the mobile-phone-based recording of electrocardiogram (ECG) signals such as personnel with minimal training and other extraneous noises. PhysioNet organized a challenge in 2011 to develop efficient algorithms that can assess the ECG signal quality in telemedicine settings. This paper presents our efforts in this challenge to integrate multiscale recurrence analysis with a self-organizing map for controlling the ECG signal quality. As opposed to directly evaluating the 12-lead ECG, we utilize an information-preserving transform, i.e. Dower transform, to derive the 3-lead vectorcardiogram (VCG) from the 12-lead ECG in the first place. Secondly, we delineate the nonlinear and nonstationary characteristics underlying the 3-lead VCG signals into multiple time-frequency scales. Furthermore, a self-organizing map is trained, in both supervised and unsupervised ways, to identify the correlations between signal quality and multiscale recurrence features. The efficacy and robustness of this approach are validated using real-world ECG recordings available from PhysioNet. The average performance was demonstrated to be 95.25% for the training dataset and 90.0% for the independent test dataset with unknown labels.

  11. Fusion of ECG and ABP signals based on wavelet transform for cardiac arrhythmias classification.

    Science.gov (United States)

    Arvanaghi, Roghayyeh; Daneshvar, Sabalan; Seyedarabi, Hadi; Goshvarpour, Atefeh

    2017-11-01

    Each of Electrocardiogram (ECG) and Atrial Blood Pressure (ABP) signals contain information of cardiac status. This information can be used for diagnosis and monitoring of diseases. The majority of previously proposed methods rely only on ECG signal to classify heart rhythms. In this paper, ECG and ABP were used to classify five different types of heart rhythms. To this end, two mentioned signals (ECG and ABP) have been fused. These physiological signals have been used from MINIC physioNet database. ECG and ABP signals have been fused together on the basis of the proposed Discrete Wavelet Transformation fusion technique. Then, some frequency features were extracted from the fused signal. To classify the different types of cardiac arrhythmias, these features were given to a multi-layer perceptron neural network. In this study, the best results for the proposed fusion algorithm were obtained. In this case, the accuracy rates of 96.6%, 96.9%, 95.6% and 93.9% were achieved for two, three, four and five classes, respectively. However, the maximum classification rate of 89% was obtained for two classes on the basis of ECG features. It has been found that the higher accuracy rates were acquired by using the proposed fusion technique. The results confirmed the importance of fusing features from different physiological signals to gain more accurate assessments. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Application of Handheld Tele-ECG for Health Care Delivery in Rural India

    Directory of Open Access Journals (Sweden)

    Meenu Singh

    2014-01-01

    Full Text Available Telemonitoring is a medical practice that involves remotely monitoring patients who are not at the same location as the health care provider. The purpose of our study was to use handheld tele-electrocardiogram (ECG developed by Bhabha Atomic Research Center (BARC to identify heart conditions in the rural underserved population where the doctor-patient ratio is low and access to health care is difficult. The objective of our study was clinical validation of handheld tele-ECG as a screening tool for evaluation of cardiac diseases in the rural population. ECG was obtained in 450 individuals (mean age 31.49 ± 20.058 residing in the periphery of Chandigarh, India, from April 2011 to March 2013, using the handheld tele-ECG machine. The data were then transmitted to physicians in Postgraduate Institute of Medical Education and Research (PGIMER, Chandigarh, for their expert opinion. ECG was interpreted as normal in 70% individuals. Left ventricular hypertrophy (9.3% was the commonest abnormality followed closely by old myocardial infarction (5.3%. Patient satisfaction was reported to be ~95%. Thus, it can be safely concluded that tele-ECG is a portable, cost-effective, and convenient tool for diagnosis and monitoring of heart diseases and thus improves quality and accessibility, especially in rural areas.

  13. Self-organized neural network for the quality control of 12-lead ECG signals

    International Nuclear Information System (INIS)

    Chen, Yun; Yang, Hui

    2012-01-01

    Telemedicine is very important for the timely delivery of health care to cardiovascular patients, especially those who live in the rural areas of developing countries. However, there are a number of uncertainty factors inherent to the mobile-phone-based recording of electrocardiogram (ECG) signals such as personnel with minimal training and other extraneous noises. PhysioNet organized a challenge in 2011 to develop efficient algorithms that can assess the ECG signal quality in telemedicine settings. This paper presents our efforts in this challenge to integrate multiscale recurrence analysis with a self-organizing map for controlling the ECG signal quality. As opposed to directly evaluating the 12-lead ECG, we utilize an information-preserving transform, i.e. Dower transform, to derive the 3-lead vectorcardiogram (VCG) from the 12-lead ECG in the first place. Secondly, we delineate the nonlinear and nonstationary characteristics underlying the 3-lead VCG signals into multiple time-frequency scales. Furthermore, a self-organizing map is trained, in both supervised and unsupervised ways, to identify the correlations between signal quality and multiscale recurrence features. The efficacy and robustness of this approach are validated using real-world ECG recordings available from PhysioNet. The average performance was demonstrated to be 95.25% for the training dataset and 90.0% for the independent test dataset with unknown labels. (paper)

  14. Differentiating ST elevation myocardial infarction and nonischemic causes of ST elevation by analyzing the presenting electrocardiogram

    DEFF Research Database (Denmark)

    Jayroe, Jason B; Spodick, David H; Nikus, Kjell

    2008-01-01

    Guidelines recommend that patients with suggestive symptoms of myocardial ischemia and ST-segment elevation (STE) in > or =2 adjacent electrocardiographic leads should receive immediate reperfusion therapy. Novel strategies aimed to reduce door-to-balloon time, such as prehospital wireless...... electrocardiographic transmission, may be dependent on the interpretation accuracy of the electrocardiogram (ECG) readers. We assessed the ability of experienced electrocardiographers to differentiate among STE, acute STE myocardial infarction (STEMI), and nonischemic STE (NISTE). A total of 116 consecutive ECGs.......13). The sensitivity and specificity of the individual readers ranged from 50% to 100% (average 75%) and 73% to 97% (average 85%), respectively. There were broad inconsistencies among the readers in the chosen reasons used to classify NISTE. In conclusion, we found wide variations among experienced...

  15. ECG compression using uniform scalar dead-zone quantization and conditional entropy coding.

    Science.gov (United States)

    Chen, Jianhua; Wang, Fuyan; Zhang, Yufeng; Shi, Xinling

    2008-05-01

    A new wavelet-based method for the compression of electrocardiogram (ECG) data is presented. A discrete wavelet transform (DWT) is applied to the digitized ECG signal. The DWT coefficients are first quantized with a uniform scalar dead-zone quantizer, and then the quantized coefficients are decomposed into four symbol streams, representing a binary significance stream, the signs, the positions of the most significant bits, and the residual bits. An adaptive arithmetic coder with several different context models is employed for the entropy coding of these symbol streams. Simulation results on several records from the MIT-BIH arrhythmia database show that the proposed coding algorithm outperforms some recently developed ECG compression algorithms.

  16. A sub-nJ CMOS ECG classifier for wireless smart sensor.

    Science.gov (United States)

    Chollet, Paul; Pallas, Remi; Lahuec, Cyril; Arzel, Matthieu; Seguin, Fabrice

    2017-07-01

    Body area sensor networks hold the promise of more efficient and cheaper medical care services through the constant monitoring of physiological markers such as heart beats. Continuously transmitting the electrocardiogram (ECG) signal requires most of the wireless ECG sensor energy budget. This paper presents the analog implantation of a classifier for ECG signals that can be embedded onto a sensor. The classifier is a sparse neural associative memory. It is implemented using the ST 65 nm CMOS technology and requires only 234 pJ per classification while achieving a 93.6% classification accuracy. The energy requirement is 6 orders of magnitude lower than a digital accelerator that performs a similar task. The lifespan of the resulting sensor is 191 times as large as that of a sensor sending all the data.

  17. Design and construction of system for telephonic transmission of Ecg signals

    International Nuclear Information System (INIS)

    Moradi, M. H.; Mazloum, J.

    2001-01-01

    With the growing use of Electrocardiogram signal for detection and diagnosis of heart disorders, the efficient transmission of this signal over telephone lines or mobile radio is becoming more and more important. A specialist in a major hospital can use the system and revive information on a patient in a rural area and send back a plan of treatment specific for that patient. In this article, we present different stage for design and fabricate an intelligent telephonic transmission System with 12-Lead Ecg. This paper includes two sections on hardware and software. The digital hardware circuitry takes benefit of an microprocessor. Microprocessor software takes hospital telephone number and transmit/receive serial data to modem. In software section a real algorithm is used to draw Ecg signal and save this digital data to remote computer hard disk and compression Ecg signal via four algorithms

  18. Wavelet-Based Watermarking and Compression for ECG Signals with Verification Evaluation

    Directory of Open Access Journals (Sweden)

    Kuo-Kun Tseng

    2014-02-01

    Full Text Available In the current open society and with the growth of human rights, people are more and more concerned about the privacy of their information and other important data. This study makes use of electrocardiography (ECG data in order to protect individual information. An ECG signal can not only be used to analyze disease, but also to provide crucial biometric information for identification and authentication. In this study, we propose a new idea of integrating electrocardiogram watermarking and compression approach, which has never been researched before. ECG watermarking can ensure the confidentiality and reliability of a user’s data while reducing the amount of data. In the evaluation, we apply the embedding capacity, bit error rate (BER, signal-to-noise ratio (SNR, compression ratio (CR, and compressed-signal to noise ratio (CNR methods to assess the proposed algorithm. After comprehensive evaluation the final results show that our algorithm is robust and feasible.

  19. ECG-based PICC tip verification system: an evaluation 5 years on.

    Science.gov (United States)

    Oliver, Gemma; Jones, Matt

    2016-10-27

    In 2011, the vascular access team at East Kent Hospitals University NHS Foundation Trust safely and successfully incorporated the use of electrocardiogram (ECG) guidance technology for verification of peripherally inserted central catheters (PICC) tip placement into their practice. This study, 5 years on, compared the strengths and limitations of using this ECG method with the previous gold-standard of post-procedural chest X-ray. The study was undertaken using an embedded case study approach, and the cost, accuracy and efficiency of both systems were evaluated and compared. Using ECG to confirm PICC tip position was found to be cheaper, quicker and more accurate than post-procedural chest X-ray.

  20. Noninvasive Fetal ECG analysis

    Science.gov (United States)

    Clifford, Gari D.; Silva, Ikaro; Behar, Joachim; Moody, George B.

    2014-01-01

    Despite the important advances achieved in the field of adult electrocardiography signal processing, the analysis of the non-invasive fetal electrocardiogram (NI-FECG) remains a challenge. Currently no gold standard database exists which provides labelled FECG QRS complexes (and other morphological parameters), and publications rely either on proprietary databases or a very limited set of data recorded from few (or more often, just one) individuals. The PhysioNet/Computing in Cardiology Challenge 2013 enables to tackle some of these limitations by releasing a set of NI-FECG data publicly to the scientific community in order to evaluate signal processing techniques for NI-FECG extraction. The Challenge aim was to encourage development of accurate algorithms for locating QRS complexes and estimating the QT interval in noninvasive FECG signals. Using carefully reviewed reference QRS annotations and QT intervals as a gold standard, based on simultaneous direct FECG when possible, the Challenge was designed to measure and compare the performance of participants’ algorithms objectively. Multiple challenge events were designed to test basic FHR estimation accuracy, as well as accuracy in measurement of inter-beat (RR) and QT intervals needed as a basis for derivation of other FECG features. This editorial reviews the background issues, the design of the Challenge, the key achievements, and the follow-up research generated as a result of the Challenge, published in the concurrent special issue of Physiological Measurement. PMID:25071093

  1. A combined application of lossless and lossy compression in ECG processing and transmission via GSM-based SMS.

    Science.gov (United States)

    Mukhopadhyay, S K; Mitra, S; Mitra, M

    2015-02-01

    This paper presents a software-based scheme for reliable and robust Electrocardiogram (ECG) data compression and its efficient transmission using Second Generation (2G) Global System for Mobile Communication (GSM) based Short Message Service (SMS). To achieve a firm lossless compression in high standard deviating QRS complex regions and an acceptable lossy compression in the rest of the signal, two different algorithms have been used. The combined compression module is such that it outputs only American Standard Code for Information Interchange (ASCII) characters and, hence, SMS service is found to be most suitable for transmitting the compressed signal. At the receiving end, the ECG signal is reconstructed using just the reverse algorithm. The module has been tested to all the 12 leads of different types of ECG signals (healthy and abnormal) collected from the PTB Diagnostic ECG Database. The compression algorithm achieves an average compression ratio of ∼22.51, without any major alteration of clinical morphology.

  2. Fetal ECG Extraction from Abdominal Signals: A Review on Suppression of Fundamental Power Line Interference Component and Its Harmonics

    Directory of Open Access Journals (Sweden)

    Dragoş-Daniel Ţarălungă

    2014-01-01

    Full Text Available Interference of power line (PLI (fundamental frequency and its harmonics is usually present in biopotential measurements. Despite all countermeasures, the PLI still corrupts physiological signals, for example, electromyograms (EMG, electroencephalograms (EEG, and electrocardiograms (ECG. When analyzing the fetal ECG (fECG recorded on the maternal abdomen, the PLI represents a particular strong noise component, being sometimes 10 times greater than the fECG signal, and thus impairing the extraction of any useful information regarding the fetal health state. Many signal processing methods for cancelling the PLI from biopotentials are available in the literature. In this review study, six different principles are analyzed and discussed, and their performance is evaluated on simulated data (three different scenarios, based on five quantitative performance indices.

  3. Left ventricular hypertrophy: The relationship between the electrocardiogram and cardiovascular magnetic resonance imaging.

    Science.gov (United States)

    Bacharova, Ljuba; Ugander, Martin

    2014-11-01

    Conventional assessment of left ventricular hypertrophy (LVH) using the electrocardiogram (ECG), for example, by the Sokolow-Lyon, Romhilt-Estes or Cornell criteria, have relied on assessing changes in the amplitude and/or duration of the QRS complex of the ECG to quantify LV mass. ECG measures of LV mass have typically been validated by imaging with echocardiography or cardiovascular magnetic resonance imaging (CMR). However, LVH can be the result of diverse etiologies, and LVH is also characterized by pathological changes in myocardial tissue characteristics on the genetic, molecular, cellular, and tissue level beyond a pure increase in the number of otherwise normal cardiomyocytes. For example, slowed conduction velocity through the myocardium, which can be due to diffuse myocardial fibrosis, has been shown to be an important determinant of conventional ECG LVH criteria regardless of LV mass. Myocardial tissue characterization by CMR has emerged to not only quantify LV mass, but also detect and quantify the extent and severity of focal or diffuse myocardial fibrosis, edema, inflammation, myocarditis, fatty replacement, myocardial disarray, and myocardial deposition of amyloid proteins (amyloidosis), glycolipids (Fabry disease), or iron (siderosis). This can be undertaken using CMR techniques including late gadolinium enhancement (LGE), T1 mapping, T2 mapping, T2* mapping, extracellular volume fraction (ECV) mapping, fat/water-weighted imaging, and diffusion tensor CMR. This review presents an overview of current and emerging concepts regarding the diagnostic possibilities of both ECG and CMR for LVH in an attempt to narrow gaps in our knowledge regarding the ECG diagnosis of LVH. © 2014 Wiley Periodicals, Inc.

  4. Accuracy of remote electrocardiogram interpretation with the use of Google Glass technology.

    Science.gov (United States)

    Jeroudi, Omar M; Christakopoulos, George; Christopoulos, George; Kotsia, Anna; Kypreos, Megan A; Rangan, Bavana V; Banerjee, Subhash; Brilakis, Emmanouil S

    2015-02-01

    We sought to investigate the accuracy of remote electrocardiogram (ECG) interpretation using Google Glass (Google, Mountain View, California). Google Glass is an optical head mounted display device with growing applications in medicine. We compared interpretation of 10 ECGs with 21 clinically important findings by faculty and fellow cardiologists by (1) viewing the electrocardiographic image at the Google Glass screen; (2) viewing a photograph of the ECG taken using Google Glass and interpreted on a mobile device; (3) viewing the original paper ECG; and (4) viewing a photograph of the ECG taken with a high-resolution camera and interpreted on a mobile device. One point was given for identification of each correct finding. Subjective rating of the user experience was also recorded. Twelve physicians (4 faculty and 8 fellow cardiologists) participated. The average electrocardiographic interpretation score (maximum 21 points) as viewed through the Google Glass, Google Glass photograph on a mobile device, on paper, and high-resolution photograph on a mobile device was 13.5 ± 1.8, 16.1 ± 2.6, 18.3 ± 1.7, and 18.6 ± 1.5, respectively (p = 0.0005 between Google Glass and mobile device, p = 0.0005 between Google Glass and paper, and p = 0.002 between mobile device and paper). Of the 12 physicians, 9 (75%) were dissatisfied with ECGs viewing on the prism display of Google Glass. In conclusion, further improvements are needed before Google Glass can be reliably used for remote electrocardiographic analysis. Published by Elsevier Inc.

  5. Envelopment filter and K-means for the detection of QRS waveforms in electrocardiogram.

    Science.gov (United States)

    Merino, Manuel; Gómez, Isabel María; Molina, Alberto J

    2015-06-01

    The electrocardiogram (ECG) is a well-established technique for determining the electrical activity of the heart and studying its diseases. One of the most common pieces of information that can be read from the ECG is the heart rate (HR) through the detection of its most prominent feature: the QRS complex. This paper describes an offline version and a real-time implementation of a new algorithm to determine QRS localization in the ECG signal based on its envelopment and K-means clustering algorithm. The envelopment is used to obtain a signal with only QRS complexes, deleting P, T, and U waves and baseline wander. Two moving average filters are applied to smooth data. The K-means algorithm classifies data into QRS and non-QRS. The technique is validated using 22 h of ECG data from five Physionet databases. These databases were arbitrarily selected to analyze different morphologies of QRS complexes: three stored data with cardiac pathologies, and two had data with normal heartbeats. The algorithm has a low computational load, with no decision thresholds. Furthermore, it does not require any additional parameter. Sensitivity, positive prediction and accuracy from results are over 99.7%. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  6. The 12-lead electrocardiogram and risk of sudden death: current utility and future prospects.

    Science.gov (United States)

    Narayanan, Kumar; Chugh, Sumeet S

    2015-10-01

    More than 100 years after it was first invented, the 12-lead electrocardiogram (ECG) continues to occupy an important place in the diagnostic armamentarium of the practicing clinician. With the recognition of relatively rare but important clinical entities such as Wolff-Parkinson-White and the long QT syndrome, this clinical tool was firmly established as a test for assessing risk of sudden cardiac death (SCD). However, over the past two decades the role of the ECG in risk prediction for common forms of SCD, for example in patients with coronary artery disease, has been the focus of considerable investigation. Especially in light of the limitations of current risk stratification approaches, there is a renewed focus on this broadly available and relatively inexpensive test. Various abnormalities of depolarization and repolarization on the ECG have been linked to SCD risk; however, more focused work is needed before they can be deployed in the clinical arena. The present review summarizes the current knowledge on various ECG risk markers for prediction of SCD and discusses some future directions in this field. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  7. Comparison of Electrocardiogram Signals in Men and Women during Creativity with Classification Approaches

    Directory of Open Access Journals (Sweden)

    Sahar ZAKERI

    2016-07-01

    Full Text Available Electrocardiogram (ECG analysis is mostly used as a valuable tool in the evaluation of cognitive tasks. By taking and analyzing measurements in vast quantities, researchers are working toward a better understanding of how human physiological systems work. For the first time, this study investigated the function of the cardiovascular system during creative thinking. In addition, the difference between male/female and normal/creativity states from ECG signals was investigated. Overall, the purpose of this paper was to illustrate the heart working during the creativity, and discover the creative men or women subjects. For these goals, six nonlinear features of the ECG signal were extracted to detect creativity states. During the three tasks of the Torrance Tests of Creative Thinking (TTCT- Figural B, ECG signals were recorded from 52 participants (26 men and 26 women. Then, the proficiency of two kinds of classification approaches was evaluated: Artificial Neural Network (ANN and Support Vector Machine (SVM. The results indicated the high accuracy rate of discriminations between male/female (96.09% and normal/creativity states (95.84% using ANN classifier. Therefore, the proposed method can be useful to detect the creativity states.

  8. Real-Time Monitoring and Analysis of Zebrafish Electrocardiogram with Anomaly Detection

    Directory of Open Access Journals (Sweden)

    Michael Lenning

    2017-12-01

    Full Text Available Heart disease is the leading cause of mortality in the U.S. with approximately 610,000 people dying every year. Effective therapies for many cardiac diseases are lacking, largely due to an incomplete understanding of their genetic basis and underlying molecular mechanisms. Zebrafish (Danio rerio are an excellent model system for studying heart disease as they enable a forward genetic approach to tackle this unmet medical need. In recent years, our team has been employing electrocardiogram (ECG as an efficient tool to study the zebrafish heart along with conventional approaches, such as immunohistochemistry, DNA and protein analyses. We have overcome various challenges in the small size and aquatic environment of zebrafish in order to obtain ECG signals with favorable signal-to-noise ratio (SNR, and high spatial and temporal resolution. In this paper, we highlight our recent efforts in zebrafish ECG acquisition with a cost-effective simplified microelectrode array (MEA membrane providing multi-channel recording, a novel multi-chamber apparatus for simultaneous screening, and a LabVIEW program to facilitate recording and processing. We also demonstrate the use of machine learning-based programs to recognize specific ECG patterns, yielding promising results with our current limited amount of zebrafish data. Our solutions hold promise to carry out numerous studies of heart diseases, drug screening, stem cell-based therapy validation, and regenerative medicine.

  9. Reclassification of cardiovascular risk by myocardial perfusion imaging in diabetic patients with abnormal resting electrocardiogram.

    Science.gov (United States)

    Petretta, M; Acampa, W; Evangelista, L; Daniele, S; Zampella, E; Assante, R; Nappi, C; Cantoni, V; Fiumara, G; Cuocolo, A

    2014-06-01

    Despite an extensive use of stress myocardial perfusion single-photon emission computed tomography (MPS), no study addressed the role of perfusion imaging in diabetic patients with abnormal resting electrocardiogram (ECG). We compared analytical approaches to assess the added value of stress MPS variables in estimating coronary heart disease outcomes in diabetic patients with abnormal resting ECG. A total of 416 patients with diabetes and abnormal resting ECG who underwent stress MPS were prospectively followed up after the index study. The end point was the occurrence of a major cardiac event, including cardiac death and nonfatal myocardial infarction. At the end of follow-up (median 58 months), 42 patients experienced events. MPS data increased the predictive value of a model including traditional cardiovascular risk factors and left ventricular (LV) ejection fraction (likelihood ratio χ² from 17.54 to 24.15, p patients were reclassified to a lower risk category, with a 5-year event rate of 3.5%, and 40 patients were reclassified to a higher risk category, with a 5-year event rate of 20%. The addition of MPS findings to a model based on traditional cardiovascular risk factors and LV ejection fraction improves risk classification for incident cardiac events in diabetic patients with abnormal resting ECG. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. The accuracy of the electrocardiogram during exercise stress test based on heart size.

    Directory of Open Access Journals (Sweden)

    Jason C Siegler

    Full Text Available BACKGROUND: Multiple studies have shown that the exercise electrocardiogram (ECG is less accurate for predicting ischemia, especially in women, and there is additional evidence to suggest that heart size may affect its diagnostic accuracy. HYPOTHESIS: The purpose of this investigation was to assess the diagnostic accuracy of the exercise ECG based on heart size. METHODS: We evaluated 1,011 consecutive patients who were referred for an exercise nuclear stress test. Patients were divided into two groups: small heart size defined as left ventricular end diastolic volume (LVEDV <65 mL (Group A and normal heart size defined as LVEDV ≥65 mL (Group B and associations between ECG outcome (false positive vs. no false positive and heart size (small vs. normal were analyzed using the Chi square test for independence, with a Yates continuity correction. LVEDV calculations were performed via a computer-processing algorithm. SPECT myocardial perfusion imaging was used as the gold standard for the presence of coronary artery disease (CAD. RESULTS: Small heart size was found in 142 patients, 123 female and 19 male patients. There was a significant association between ECG outcome and heart size (χ(2 = 4.7, p = 0.03, where smaller hearts were associated with a significantly greater number of false positives. CONCLUSIONS: This study suggests a possible explanation for the poor diagnostic accuracy of exercise stress testing, especially in women, as the overwhelming majority of patients with small heart size were women.

  11. Knowledge and Utilization of Electrocardiogram among Resident ...

    African Journals Online (AJOL)

    2017-10-26

    Oct 26, 2017 ... knowledge and utilization of ECG among family medicine residents in Nigeria. Materials and Methods: A cross-sectional evaluation was conducted between. November 2011 and May 2012 in four family ..... study on ECG interpretative skills and challenges among family physicians. The utilization of ECG ...

  12. Multiscale permutation entropy analysis of electrocardiogram

    Science.gov (United States)

    Liu, Tiebing; Yao, Wenpo; Wu, Min; Shi, Zhaorong; Wang, Jun; Ning, Xinbao

    2017-04-01

    To make a comprehensive nonlinear analysis to ECG, multiscale permutation entropy (MPE) was applied to ECG characteristics extraction to make a comprehensive nonlinear analysis of ECG. Three kinds of ECG from PhysioNet database, congestive heart failure (CHF) patients, healthy young and elderly subjects, are applied in this paper. We set embedding dimension to 4 and adjust scale factor from 2 to 100 with a step size of 2, and compare MPE with multiscale entropy (MSE). As increase of scale factor, MPE complexity of the three ECG signals are showing first-decrease and last-increase trends. When scale factor is between 10 and 32, complexities of the three ECG had biggest difference, entropy of the elderly is 0.146 less than the CHF patients and 0.025 larger than the healthy young in average, in line with normal physiological characteristics. Test results showed that MPE can effectively apply in ECG nonlinear analysis, and can effectively distinguish different ECG signals.

  13. Value of the Signal-Averaged Electrocardiogram in Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia

    Science.gov (United States)

    Kamath, Ganesh S.; Zareba, Wojciech; Delaney, Jessica; Koneru, Jayanthi N.; McKenna, William; Gear, Kathleen; Polonsky, Slava; Sherrill, Duane; Bluemke, David; Marcus, Frank; Steinberg, Jonathan S.

    2011-01-01

    Background Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is an inherited disease causing structural and functional abnormalities of the right ventricle (RV). The presence of late potentials as assessed by the signal averaged electrocardiogram (SAECG) is a minor Task Force criterion. Objective The purpose of this study was to examine the diagnostic and clinical value of the SAECG in a large population of genotyped ARVC/D probands. Methods We compared the SAECGs of 87 ARVC/D probands (age 37 ± 13 years, 47 males) diagnosed as affected or borderline by Task Force criteria without using the SAECG criterion with 103 control subjects. The association of SAECG abnormalities was also correlated with clinical presentation; surface ECG; VT inducibility at electrophysiologic testing; ICD therapy for VT; and RV abnormalities as assessed by cardiac magnetic resonance imaging (cMRI). Results When compared with controls, all 3 components of the SAECG were highly associated with the diagnosis of ARVC/D (p<0.001). These include the filtered QRS duration (fQRSD) (97.8 ± 8.7 msec vs. 119.6 ± 23.8 msec), low amplitude signal (LAS) (24.4 ± 9.2 msec vs. 46.2 ± 23.7 msec) and root mean square amplitude of the last 40 msec of late potentials (RMS-40) (50.4 ± 26.9 µV vs. 27.9 ± 36.3 µV). The sensitivity of using SAECG for diagnosis of ARVC/D was increased from 47% using the established 2 of 3 criteria (i.e. late potentials) to 69% by using a modified criterion of any 1 of the 3 criteria, while maintaining a high specificity of 95%. Abnormal SAECG as defined by this modified criteria was associated with a dilated RV volume and decreased RV ejection fraction detected by cMRI (p<0.05). SAECG abnormalities did not vary with clinical presentation or reliably predict spontaneous or inducible VT, and had limited correlation with ECG findings. Conclusion Using 1 of 3 SAECG criteria contributed to increased sensitivity and specificity for the diagnosis of ARVC/D. This

  14. Piezoelectric extraction of ECG signal

    Science.gov (United States)

    Ahmad, Mahmoud Al

    2016-11-01

    The monitoring and early detection of abnormalities or variations in the cardiac cycle functionality are very critical practices and have significant impact on the prevention of heart diseases and their associated complications. Currently, in the field of biomedical engineering, there is a growing need for devices capable of measuring and monitoring a wide range of cardiac cycle parameters continuously, effectively and on a real-time basis using easily accessible and reusable probes. In this paper, the revolutionary generation and extraction of the corresponding ECG signal using a piezoelectric transducer as alternative for the ECG will be discussed. The piezoelectric transducer pick up the vibrations from the heart beats and convert them into electrical output signals. To this end, piezoelectric and signal processing techniques were employed to extract the ECG corresponding signal from the piezoelectric output voltage signal. The measured electrode based and the extracted piezoelectric based ECG traces are well corroborated. Their peaks amplitudes and locations are well aligned with each other.

  15. The Electrocardiogram as an Example of Electrostatics

    Science.gov (United States)

    Hobbie, Russell K.

    1973-01-01

    Develops a simplified electrostatic model of the heart with conduction within the torso neglected to relate electrocardiogram patterns to the charge distribution within the myocardium. Suggests its application to explanation of Coulomb's law in general physics. (CC)

  16. Ecg manifestations in dengue infection

    International Nuclear Information System (INIS)

    Tarique, S.; Murtaza, G.; Asif, S.; Qureshi, I.H.

    2013-01-01

    To determine the frequency of ECG changes in patients with dengue fever and dengue hemorrhagic fever. Place of study: Department of Medicine, Mayo Hospital Lahore Duration of study: September to November 201 Study design: Cross sectional analytical study Patient and methods: 116 patients with dengue infection were enrolled in the study. Their clinical presentation and examination was duly noted. Each patient had baseline and then regular monitoring of blood counts, metabolic profile and fluid status. Patients with Dengue Hemorrhagic fever underwent radiological examination in form of chest radiograph and ultrasound abdomen. ECG was carried out in all patients. Results: Out of 116 patients, 61(52.6%) suffered from Dengue Fever and 55(47.4%) had Dengue Hemorrhagic Fever. Overall 78 patients had normal ECG. Abnormal ECG findings like tachycardia, bradycardia, supraventricular tachycardia, left bundle branch block, ST depression, poor progression of R wave were noted. There was no significant relationship of ECG findings with the disease. Conclusion: ECG changes can occur in dengue infection with or without cardiac symptoms. Commonly noted findings were ST depression and bradycardia. (author)

  17. Educational technology improves ECG interpretation of acute myocardial infarction among medical students and emergency medicine residents.

    Science.gov (United States)

    Pourmand, Ali; Tanski, Mary; Davis, Steven; Shokoohi, Hamid; Lucas, Raymond; Zaver, Fareen

    2015-01-01

    Asynchronous online training has become an increasingly popular educational format in the new era of technology-based professional development. We sought to evaluate the impact of an online asynchronous training module on the ability of medical students and emergency medicine (EM) residents to detect electrocardiogram (ECG) abnormalities of an acute myocardial infarction (AMI). We developed an online ECG training and testing module on AMI, with emphasis on recognizing ST elevation myocardial infarction (MI) and early activation of cardiac catheterization resources. Study participants included senior medical students and EM residents at all post-graduate levels rotating in our emergency department (ED). Participants were given a baseline set of ECGs for interpretation. This was followed by a brief interactive online training module on normal ECGs as well as abnormal ECGs representing an acute MI. Participants then underwent a post-test with a set of ECGs in which they had to interpret and decide appropriate intervention including catheterization lab activation. 148 students and 35 EM residents participated in this training in the 2012-2013 academic year. Students and EM residents showed significant improvements in recognizing ECG abnormalities after taking the asynchronous online training module. The mean score on the testing module for students improved from 5.9 (95% CI [5.7-6.1]) to 7.3 (95% CI [7.1-7.5]), with a mean difference of 1.4 (95% CI [1.12-1.68]) (p<0.0001). The mean score for residents improved significantly from 6.5 (95% CI [6.2-6.9]) to 7.8 (95% CI [7.4-8.2]) (p<0.0001). An online interactive module of training improved the ability of medical students and EM residents to correctly recognize the ECG evidence of an acute MI.

  18. Arrhythmia recognition and classification using combined linear and nonlinear features of ECG signals.

    Science.gov (United States)

    Elhaj, Fatin A; Salim, Naomie; Harris, Arief R; Swee, Tan Tian; Ahmed, Taqwa

    2016-04-01

    Arrhythmia is a cardiac condition caused by abnormal electrical activity of the heart, and an electrocardiogram (ECG) is the non-invasive method used to detect arrhythmias or heart abnormalities. Due to the presence of noise, the non-stationary nature of the ECG signal (i.e. the changing morphology of the ECG signal with respect to time) and the irregularity of the heartbeat, physicians face difficulties in the diagnosis of arrhythmias. The computer-aided analysis of ECG results assists physicians to detect cardiovascular diseases. The development of many existing arrhythmia systems has depended on the findings from linear experiments on ECG data which achieve high performance on noise-free data. However, nonlinear experiments characterize the ECG signal more effectively sense, extract hidden information in the ECG signal, and achieve good performance under noisy conditions. This paper investigates the representation ability of linear and nonlinear features and proposes a combination of such features in order to improve the classification of ECG data. In this study, five types of beat classes of arrhythmia as recommended by the Association for Advancement of Medical Instrumentation are analyzed: non-ectopic beats (N), supra-ventricular ectopic beats (S), ventricular ectopic beats (V), fusion beats (F) and unclassifiable and paced beats (U). The characterization ability of nonlinear features such as high order statistics and cumulants and nonlinear feature reduction methods such as independent component analysis are combined with linear features, namely, the principal component analysis of discrete wavelet transform coefficients. The features are tested for their ability to differentiate different classes of data using different classifiers, namely, the support vector machine and neural network methods with tenfold cross-validation. Our proposed method is able to classify the N, S, V, F and U arrhythmia classes with high accuracy (98.91%) using a combined support

  19. Comparison of infarct size changes with delayed contrast-enhanced magnetic resonance imaging and electrocardiogram QRS scoring during the 6 months after acutely reperfused myocardial infarction

    DEFF Research Database (Denmark)

    Bang, L.E.; Ripa, R.S.; Grande, P.

    2008-01-01

    that has infarcted. There are no comparison of serial changes on ECG and DE-MRI measuring infarct size. AIM: The general aim of this study was to describe the acute, healing, and chronic phases of the changes in infarct size estimated by the ECG and DE-MRI. The specific aim was to compare estimates......INTRODUCTION: Magnetic resonance imaging using the delayed contrast-enhanced (DE-MRI) method can be used for characterizing and quantifying myocardial infarction (MI). Electrocardiogram (ECG) score after the acute phase of MI can be used to estimate the portion of left ventricular myocardium...... of the Selvester QRS scoring system and DE-MRI to identify the difference between the extent of left ventricle occupied by infarction in the acute and chronic phases. METHODS: In 31 patients (26 men, age 56 +/- 9) with reperfused ST-elevation MI (11 anterior, 20 inferior), standard 12-lead ECG and DE-MRI were...

  20. Early repolarization of surface ECG predicts fatal ventricular arrhythmias in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy and symptomatic ventricular arrhythmias.

    Science.gov (United States)

    Chan, Chao-Shun; Lin, Yenn-Jiang; Chang, Shih-Lin; Lo, Li-Wei; Hu, Yu-Feng; Chao, Tze-Fan; Chung, Fa-Po; Liao, Jo-Nan; Chen, Yi-Jen; Chen, Shih-Ann

    2015-10-15

    The clinical characteristics and prognostic value of early repolarization (ER) in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) and symptomatic ventricular arrhythmias remain unclear. We investigated the prevalence, clinical features, and cardiovascular outcomes of patients with symptomatic ARVD/C and ER. A total of 59 consecutive ARVD/C patients hospitalized for catheter ablation, presenting with and without J-point elevations of ≥0.1mV in at least 2 inferior leads or lateral leads were enrolled. Clinical characteristics, electrophysiological study, substrate mapping, catheter ablation, and future clinical outcomes in a prospective patient registry were investigated. ER was observed in 38 patients (64.4%). Among these patients, ER was found in the inferior leads in 18 patients (47.4%), in the lateral leads in 2 patients (5.3%), and in both inferior and lateral leads in 18 patients (47.4%). Patients exhibiting ER were commonly men, had lower right ventricular ejection fraction, had higher incidence of clinical ventricular fibrillation or aborted sudden cardiac death, had more defibrillator implantations, had higher the need of epicardial ablation, and had more major criteria according to the task force criteria. Significant higher incidence of induced ventricular fibrillation and shorter tachycardia cycle length of induced ventricular tachycardia were found during procedure. The recurrence rate of ventricular arrhythmias did not differ between patients with and without ER after catheter ablation. A high prevalence of electrocardiographic ER was found among symptomatic ARVD/C patients undergoing catheter ablation. ER in 12-lead ECG is associated with an increased risk of clinical fatal ventricular arrhythmias. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. ST-segment elevation on intracoronary electrocardiogram after percutaneous coronary intervention is associated with worse outcome in patients with non-ST-segment elevation myocardial infarction.

    Science.gov (United States)

    Hishikari, Keiichi; Kakuta, Tsunekazu; Lee, Tetsumin; Murai, Tadashi; Yonetsu, Taishi; Isobe, Mitsuaki

    2016-03-01

    We sought to examine whether intracoronary electrocardiogram (IC-ECG) assessment in patients with non-ST-segment elevation myocardial infarction (NSTEMI) can predict cardiac outcomes. There has been no data correlating myocardial damage and cardiac events with an IC-ECG ST-segment change after percutaneous coronary intervention (PCI) in NSTEMI patients. We examined 111 NSTEMI patients undergoing PCI with an IC-ECG recording. IC-ECG ST-segment elevation (STE) was defined as >0.1 mV in the risk area, located by placing the guidewire distal to the culprit lesion. Clinical characteristics and in-hospital and long-term follow-up adverse cardiac event rates were compared between IC-ECG STE and non-IC-ECG STE groups at the completion of PCI. IC-ECG STE was observed in 36 patients (32.4%) immediately after PCI. Peak cardiac biomarkers were significantly elevated in patients with IC-ECG STE versus those without (cardiac troponin I 31.9 ng/mL (18.0-104.5) vs. 8.2 ng/mL (1.8-21.4); P < 0.001). At a median follow-up of 35 months, the cardiac event free rate was significantly worse in patients with IC-ECG STE than in those without (long-rank test χ(2) = 10.9; P = 0.001). Cox proportional hazards analysis showed IC-ECG STE (hazard ratio, 2.54; 95% confidence interval [CI], 1.38-4.70; P = 0.003) was an independent predictors of cardiac events. The present study suggests that presence of IC-ECG STE might help identify high-risk NSTEMI patients with greater myocardial injury leading to adverse cardiac events. © 2015 Wiley Periodicals, Inc.

  2. Diagnostic Accuracy of a New Cardiac Electrical Biomarker for Detection of Electrocardiogram Changes Suggestive of Acute Myocardial Ischemic Injury

    Science.gov (United States)

    Schreck, David M; Fishberg, Robert D

    2014-01-01

    Objective A new cardiac “electrical” biomarker (CEB) for detection of 12-lead electrocardiogram (ECG) changes indicative of acute myocardial ischemic injury has been identified. Objective was to test CEB diagnostic accuracy. Methods This is a blinded, observational retrospective case-control, noninferiority study. A total of 508 ECGs obtained from archived digital databases were interpreted by cardiologist and emergency physician (EP) blinded reference standards for presence of acute myocardial ischemic injury. CEB was constructed from three ECG cardiac monitoring leads using nonlinear modeling. Comparative active controls included ST voltage changes (J-point, ST area under curve) and a computerized ECG interpretive algorithm (ECGI). Training set of 141 ECGs identified CEB cutoffs by receiver-operating-characteristic (ROC) analysis. Test set of 367 ECGs was analyzed for validation. Poor-quality ECGs were excluded. Sensitivity, specificity, and negative and positive predictive values were calculated with 95% confidence intervals. Adjudication was performed by consensus. Results CEB demonstrated noninferiority to all active controls by hypothesis testing. CEB adjudication demonstrated 85.3–94.4% sensitivity, 92.5–93.0% specificity, 93.8–98.6% negative predictive value, and 74.6–83.5% positive predictive value. CEB was superior against all active controls in EP analysis, and against ST area under curve and ECGI by cardiologist. Conclusion CEB detects acute myocardial ischemic injury with high diagnostic accuracy. CEB is instantly constructed from three ECG leads on the cardiac monitor and displayed instantly allowing immediate cost-effective identification of patients with acute ischemic injury during cardiac rhythm monitoring. PMID:24118724

  3. Cadmium stress assessment based on the electrocardiogram characteristics of zebra fish (Danio rerio): QRS complex could play an important role.

    Science.gov (United States)

    Xing, Na; Ji, Lizhen; Song, Jie; Ma, Jingchun; Li, Shangge; Ren, Zongming; Xu, Fei; Zhu, Jianping

    2017-10-01

    The electrocardiogram (ECG) of zebra fish (Danio rerio) expresses cardiac features that are similar to humans. Here we use sharp microelectrode measurements to obtain ECG characteristics in adult zebra fish and analyze the effects of cadmium chloride (CdCl 2 ) on the heart. We observe the overall changes of ECG parameters in different treatments (0.1 TU, 0.5 TU and 1.0 TU CdCl 2 ), including P wave, Q wave, R wave, S wave, T wave, PR interval (atrial contraction), QRS complex (ventricular depolarization), ST segment, and QT interval (ventricular repolarization). The trends of the ECG parameters showed some responses to the concentration and exposure time of CdCl 2 , but it was difficult to obtain more information about the useful indicators in water quality assessment depending on tendency analysis alone. A self-organizing map (SOM) showed that P values, R values, and T values were similar; R wave and T wave amplitude were similar; and most important, QRS value was similar to the CdCl 2 stress according to the classified data patterns including CdCl 2 stress (E) and ECG components based on the Ward linkage. It suggested that the duration of QRS complex was related to environmental stress E directly. The specification and evaluation of ECG parameters in Cd 2+ pollution suggested that there is a markedly significant correlation between QRS complex and CdCl 2 stress with the highest r (0.729) and the smallest p (0.002) among all ECG characteristics. In this case, it is concluded that QRS complex can be used as an indicator in the CdCl 2 stress assessment due to the lowest AIC data abased on the linear regression model between the CdCl 2 stress and ECG parameters. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. A novel LabVIEW-based multi-channel non-invasive abdominal maternal-fetal electrocardiogram signal generator.

    Science.gov (United States)

    Martinek, Radek; Kelnar, Michal; Koudelka, Petr; Vanus, Jan; Bilik, Petr; Janku, Petr; Nazeran, Homer; Zidek, Jan

    2016-02-01

    This paper describes the design, construction, and testing of a multi-channel fetal electrocardiogram (fECG) signal generator based on LabVIEW. Special attention is paid to the fetal heart development in relation to the fetus' anatomy, physiology, and pathology. The non-invasive signal generator enables many parameters to be set, including fetal heart rate (FHR), maternal heart rate (MHR), gestational age (GA), fECG interferences (biological and technical artifacts), as well as other fECG signal characteristics. Furthermore, based on the change in the FHR and in the T wave-to-QRS complex ratio (T/QRS), the generator enables manifestations of hypoxic states (hypoxemia, hypoxia, and asphyxia) to be monitored while complying with clinical recommendations for classifications in cardiotocography (CTG) and fECG ST segment analysis (STAN). The generator can also produce synthetic signals with defined properties for 6 input leads (4 abdominal and 2 thoracic). Such signals are well suited to the testing of new and existing methods of fECG processing and are effective in suppressing maternal ECG while non-invasively monitoring abdominal fECG. They may also contribute to the development of a new diagnostic method, which may be referred to as non-invasive trans-abdominal CTG +  STAN. The functional prototype is based on virtual instrumentation using the LabVIEW developmental environment and its associated data acquisition measurement cards (DAQmx). The generator also makes it possible to create synthetic signals and measure actual fetal and maternal ECGs by means of bioelectrodes.

  5. ECG-Based Measurements of Drug-induced Repolarization Changes

    DEFF Research Database (Denmark)

    Bhuiyan, Tanveer Ahmed

    The purpose of this thesis is to investigate the abnormal repolarization both in the cellular and the surface ECG along with their relationship. It has been identified that the certain morphological changes of the monophasic action potential are predictor of TdP arrhythmia. Therefore the proporti......The purpose of this thesis is to investigate the abnormal repolarization both in the cellular and the surface ECG along with their relationship. It has been identified that the certain morphological changes of the monophasic action potential are predictor of TdP arrhythmia. Therefore...... the proportional changes of the surface ECG which corresponds to the arrhythmia-triggering MAP morphology is warranted to increase the confidence of determining cardiotoxicity of drugs....

  6. 1.5 Tesla MRI-Conditional 12-lead ECG for MR Imaging and Intra-MR Intervention

    Science.gov (United States)

    Tse, Zion Tsz Ho; Dumoulin, Charles L.; Clifford, Gari D.; Schweitzer, Jeff; Qin, Lei; Oster, Julien; Jerosch-Herold, Michael; Kwong, Raymond Y.; Michaud, Gregory; Stevenson, William G.; Schmidt, Ehud J.

    2013-01-01

    Propose High-fidelity 12-lead Electrocardiogram (ECG) is important for physiological monitoring of patients during MR-guided intervention and cardiac MR imaging. Issues in obtaining non-corrupted ECGs inside MRI include a superimposed Magneto-Hydro-Dynamic (MHD) voltage, gradient-switching induced-voltages, and radiofrequency (RF) heating. These problems increase with magnetic field. We intended to develop and clinically validate a 1.5T MRI-conditional 12-lead ECG system. Methods The system was constructed, including transmission-lines to reduce radio-frequency induction, and switching-circuits to remove induced voltages. Adaptive filters, trained by 12-lead measurements outside MRI and in two orientations inside MRI, were used to remove MHD. The system was tested on ten (one exercising) volunteers and four arrhythmia patients. Results Switching circuits removed most imaging-induced voltages (residual noise ECGs that varied by ECGs separated PVC and sinus-rhythm beats. Measured heating was ECG processing. Conclusion High-fidelity intra-MRI 12-lead ECG is possible. PMID:23580148

  7. The highly-cited Electrocardiogram-related articles in science citation index expanded: characteristics and hotspots.

    Science.gov (United States)

    Yang, Xianglin; Gu, Jiaojiao; Yan, Hong; Xu, Zhi; Ren, Bing; Yang, Yaming; Yang, Xiaodong; Chen, Qi; Tan, Shaohua

    2014-01-01

    We used bibliometric analysis methodology in the expanded Science Citation Index to identify highly-cited electrocardiogram (ECG)-related articles with total citations (TC2012) exceeding 100 from the publication year to 2012. Web of Science search tools were used to identify the highly-cited articles. The aspects analyzed for highly cited publications included effect of time on citation analysis, journals and Web of Science categories, number of authors per publication, originating institutions and countries, total citation and total citation per year life cycles of articles (C2012) and research hotspots. Results showed that a total of 467 electrocardiogram-related publications were regarded as the highly-cited publications. TC2012 ranged from 101 to 2879, with 215 as the average number of citations. No highly-cited publications have emerged yet during the first two years of the present 2010 Decade. All 11 countries and institutions originating highly-cited ECG-related publications were developed countries, USA in 9 of them. Four subject categories were identified as hotspots by total citations TC2012 and C2012: atrial fibrillation, long QT syndrome, angina and myocardial infarction, and risk factor analysis and health evaluation. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. How to read an electrocardiogram (ECG). Part 1: Basic principles of ...

    African Journals Online (AJOL)

    Angel_D

    This gives: ▫ The type of review (e.g. Intervention) title. ▫ Authors and their contacts. ▫ The Cochrane Group it is part of. ▫ Date of publication. ▫ Date of currency review. The citation is also written out. Copy this exactly when referencing the Review in any context - numbers and all! Moving down the abstract you will note that the.

  9. On the Design of an Efficient Cardiac Health Monitoring System Through Combined Analysis of ECG and SCG Signals.

    Science.gov (United States)

    Sahoo, Prasan Kumar; Thakkar, Hiren Kumar; Lin, Wen-Yen; Chang, Po-Cheng; Lee, Ming-Yih

    2018-01-28

    Cardiovascular disease (CVD) is a major public concern and socioeconomic problem across the globe. The popular high-end cardiac health monitoring systems such as magnetic resonance imaging (MRI), computerized tomography scan (CT scan), and echocardiography (Echo) are highly expensive and do not support long-term continuous monitoring of patients without disrupting their activities of daily living (ADL). In this paper, the continuous and non-invasive cardiac health monitoring using unobtrusive sensors is explored aiming to provide a feasible and low-cost alternative to foresee possible cardiac anomalies in an early stage. It is learned that cardiac health monitoring based on sole usage of electrocardiogram (ECG) signals may not provide powerful insights as ECG provides shallow information on various cardiac activities in the form of electrical impulses only. Hence, a novel low-cost, non-invasive seismocardiogram (SCG) signal along with ECG signals are jointly investigated for the robust cardiac health monitoring. For this purpose, the in-laboratory data collection model is designed for simultaneous acquisition of ECG and SCG signals followed by mechanisms for the automatic delineation of relevant feature points in acquired ECG and SCG signals. In addition, separate feature points based novel approach is adopted to distinguish between normal and abnormal morphology in each ECG and SCG cardiac cycle. Finally, a combined analysis of ECG and SCG is carried out by designing a Naïve Bayes conditional probability model. Experiments on Institutional Review Board (IRB) approved licensed ECG/SCG signals acquired from real subjects containing 12,000 cardiac cycles show that the proposed feature point delineation mechanisms and abnormal morphology detection methods consistently perform well and give promising results. In addition, experimental results show that the combined analysis of ECG and SCG signals provide more reliable cardiac health monitoring compared to the

  10. The R-wave deflection interval in lead V3 combining with R-wave amplitude index in lead V1: a new surface ECG algorithm for distinguishing left from right ventricular outflow tract tachycardia origin in patients with transitional lead at V3.

    Science.gov (United States)

    Cheng, Zhongwei; Cheng, Kang'an; Deng, Hua; Chen, Taibo; Gao, Peng; Zhu, Kongbo; Fang, Quan

    2013-09-30

    To distinguish left ventricular outflow tract (LVOT) from right ventricular outflow tract (RVOT) origin in idiopathic premature ventricular contractions or ventricular tachycardia (PVCs/VT) patients with transitional lead at V3 is still a challenge. We sought to develop a new electrocardiography (ECG) algorithm for distinguishing LVOT from RVOT origin in patients with idiopathic outflow tract PVCs/VT with precordial transitional lead at V3. We analyzed the surface ECG characteristics in a retrospective cohort of idiopathic PVCs/VT patients with transitional lead at V3 who underwent successful radiofrequency catheter ablation and developed a new surface ECG algorithm, then validated it in a prospective cohort. A total of 82 consecutive patients (47 ± 17 years, 39% male) underwent radiofrequency catheter ablation of idiopathic outflow tract PVCs/VT between January 2006 and August 2010. Among them, 31 patients (38%) with transitional lead at V3 constituted the retrospective cohort. Based on the areas under the receiver operating characteristic curves, R-wave deflection interval in lead V3>80 ms and R-wave amplitude index in lead V1>0.30 were selected to develop the new surface ECG algorithm. It correctly identified the origin sites of eleven from 12 patients in the prospective cohort, yielding the accuracy of 91.7%. We presented a new simple surface ECG algorithm, R-wave deflection interval in lead V3>80 ms combining with R-wave amplitude index in lead V1>0.30 which can reliably distinguish LVOT from RVOT origin in idiopathic outflow tract PVCs/VT in patients with transitional lead at V3. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  11. ST-segment deviation on the admission electrocardiogram, treatment strategy, and outcome in non-ST-elevation acute coronary syndromes - A substudy of the Invasive versus Conservative Treatment in Unstable coronary Syndromes (ICTUS) Trial

    NARCIS (Netherlands)

    Windhausen, Fons; Hirsch, Alexander; Tijssen, Jan G. P.; Cornel, Jan Hein; Verheugt, Freek W. A.; Klees, Margriet I.; de Winter, Robbert J.

    2007-01-01

    Background: We assessed the prognostic significance of the presence of cumulative (Sigma) ST-segment deviation on the admission electrocardiogram (ECG) in patients with non-ST-elevation acute coronary syndrome and an elevated troponin T randomized to a selective invasive (SI) or an early invasive

  12. Effect on treatment delay of prehospital teletransmission of 12-lead electrocardiogram to a cardiologist for immediate triage and direct referral of patients with ST-segment elevation acute myocardial infarction to primary percutaneous coronary intervention

    DEFF Research Database (Denmark)

    Sejersten, M.; Sillesen, M.; Hansen, Peter Riis

    2008-01-01

    Prehospital electrocardiogram (ECG) transmission to hospitals was shown to reduce time to treatment in patients with acute myocardial infarction. However, new technologies allow transmission directly to a mobile unit so an attending physician can respond irrespective of presence within or outside...

  13. Real-time QRS detection using integrated variance for ECG gated cardiac MRI

    Directory of Open Access Journals (Sweden)

    Schmidt Marcus

    2016-09-01

    Full Text Available During magnetic resonance imaging (MRI, a patient’s vital signs are required for different purposes. In cardiac MRI (CMR, an electrocardiogram (ECG of the patient is required for triggering the image acquisition process. However, a reliable QRS detection of an ECG signal acquired inside an MRI scanner is a challenging task due to the magnetohydrodynamic (MHD effect which interferes with the ECG. The aim of this work was to develop a reliable QRS detector usable inside the MRI which also fulfills the standards for medical devices (IEC 60601-2-27. Therefore, a novel real-time QRS detector based on integrated variance measurements is presented. The algorithm was trained on ANSI/AAMI EC13 test waveforms and was then applied to two databases with 12-lead ECG signals recorded inside and outside an MRI scanner. Reliable results for both databases were achieved for the ECG signals recorded inside (DBMRI: sensitivity Se = 99.94%, positive predictive value +P = 99.84% and outside (DBInCarT: Se = 99.29%, +P = 99.72% the MRI. Due to the accurate R-peak detection in real-time this can be used for monitoring and triggering in MRI exams.

  14. Non-Invasive Blood Pressure Estimation from ECG Using Machine Learning Techniques.

    Science.gov (United States)

    Simjanoska, Monika; Gjoreski, Martin; Gams, Matjaž; Madevska Bogdanova, Ana

    2018-04-11

    Blood pressure (BP) measurements have been used widely in clinical and private environments. Recently, the use of ECG monitors has proliferated; however, they are not enabled with BP estimation. We have developed a method for BP estimation using only electrocardiogram (ECG) signals. Raw ECG data are filtered and segmented, and, following this, a complexity analysis is performed for feature extraction. Then, a machine-learning method is applied, combining a stacking-based classification module and a regression module for building systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure (MAP) predictive models. In addition, the method allows a probability distribution-based calibration to adapt the models to a particular user. Using ECG recordings from 51 different subjects, 3129 30-s ECG segments are constructed, and seven features are extracted. Using a train-validation-test evaluation, the method achieves a mean absolute error (MAE) of 8.64 mmHg for SBP, 18.20 mmHg for DBP, and 13.52 mmHg for the MAP prediction. When models are calibrated, the MAE decreases to 7.72 mmHg for SBP, 9.45 mmHg for DBP and 8.13 mmHg for MAP. The experimental results indicate that, when a probability distribution-based calibration is used, the proposed method can achieve results close to those of a certified medical device for BP estimation.

  15. Home labour induction with retrievable prostaglandin pessary and continuous telemetric trans-abdominal fetal ECG monitoring.

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    Zubair Rauf

    Full Text Available OBJECTIVE: To evaluate the feasibility of continuous telemetric trans-abdominal fetal electrocardiogram (a-fECG in women undergoing labour induction at home. STUDY DESIGN: Low risk women with singleton term pregnancy undergoing labour induction with retrievable, slow-release dinoprostone pessaries (n = 70 were allowed home for up to 24 hours, while a-fECG and uterine activity were monitored in hospital via wireless technology. Semi-structured diaries were analysed using a combined descriptive and interpretive approach. RESULTS: 62/70 women (89% had successful home monitoring; 8 women (11% were recalled because of signal loss. Home monitoring lasted between 2-22 hours (median 10 hours. Good quality signal was achieved most of the time (86%, SD 10%. 3 women were recalled back to hospital for suspicious a-fECG. In 2 cases suspicious a-fECG persisted, requiring Caesarean section after recall to hospital. 48/51 women who returned the diary coped well (94%; 46/51 were satisfied with home monitoring (90%. CONCLUSIONS: Continuous telemetric trans-abdominal fetal ECG monitoring of ambulatory women undergoing labour induction is feasible and acceptable to women.

  16. ECG signal quality during arrhythmia and its application to false alarm reduction.

    Science.gov (United States)

    Behar, Joachim; Oster, Julien; Li, Qiao; Clifford, Gari D

    2013-06-01

    An automated algorithm to assess electrocardiogram (ECG) quality for both normal and abnormal rhythms is presented for false arrhythmia alarm suppression of intensive care unit (ICU) monitors. A particular focus is given to the quality assessment of a wide variety of arrhythmias. Data from three databases were used: the Physionet Challenge 2011 dataset, the MIT-BIH arrhythmia database, and the MIMIC II database. The quality of more than 33 000 single-lead 10 s ECG segments were manually assessed and another 12 000 bad-quality single-lead ECG segments were generated using the Physionet noise stress test database. Signal quality indices (SQIs) were derived from the ECGs segments and used as the inputs to a support vector machine classifier with a Gaussian kernel. This classifier was trained to estimate the quality of an ECG segment. Classification accuracies of up to 99% on the training and test set were obtained for normal sinus rhythm and up to 95% for arrhythmias, although performance varied greatly depending on the type of rhythm. Additionally, the association between 4050 ICU alarms from the MIMIC II database and the signal quality, as evaluated by the classifier, was studied. Results suggest that the SQIs should be rhythm specific and that the classifier should be trained for each rhythm call independently. This would require a substantially increased set of labeled data in order to train an accurate algorithm.

  17. Automated Diagnosis of Myocardial Infarction ECG Signals Using Sample Entropy in Flexible Analytic Wavelet Transform Framework

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    Mohit Kumar

    2017-09-01

    Full Text Available Myocardial infarction (MI is a silent condition that irreversibly damages the heart muscles. It expands rapidly and, if not treated timely, continues to damage the heart muscles. An electrocardiogram (ECG is generally used by the clinicians to diagnose the MI patients. Manual identification of the changes introduced by MI is a time-consuming and tedious task, and there is also a possibility of misinterpretation of the changes in the ECG. Therefore, a method for automatic diagnosis of MI using ECG beat with flexible analytic wavelet transform (FAWT method is proposed in this work. First, the segmentation of ECG signals into beats is performed. Then, FAWT is applied to each ECG beat, which decomposes them into subband signals. Sample entropy (SEnt is computed from these subband signals and fed to the random forest (RF, J48 decision tree, back propagation neural network (BPNN, and least-squares support vector machine (LS-SVM classifiers to choose the highest performing one. We have achieved highest classification accuracy of 99.31% using LS-SVM classifier. We have also incorporated Wilcoxon and Bhattacharya ranking methods and observed no improvement in the performance. The proposed automated method can be installed in the intensive care units (ICUs of hospitals to aid the clinicians in confirming their diagnosis.

  18. Changes in canine electrocardiogram values from three thermal floors in Cundinamarca, Colombia

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    Marta Elena Sánchez Klinge

    2008-06-01

    Full Text Available The electrocardiogram is a written register of electric changes that take place in the heart during a heart cycle. The voltage changes are the result of depolarization and repolarization of heart muscle fibers that produce electric changes able to reach body surface and that are detected by electrodes connected to a galvanometer called electrocardiograph. Heart problems are detected with the electrocardiogram, but it is necessary to know the normal values of canine electrocardiogram in a tropical country because values can change compared with normal values reported in other places. The purpose is to show variations of electrocardiogram values from clinically healthy canines from Bogotá D. C at 2600 mosl, Fusagasugá at 1700 mosl and Girardot at 326 mosl. Studied animals were separated in six groups depending on the altitude over sea level and the animal weight (less than 15 Kg and more than 15 Kg. The electrocardiograms were taken with a one channel portable electrocardiograph and derivations I, II, III, aVR, aVL, aVF, CV6LL, CV6LU, CV5RL and V10 were included. Significant differences of electrocardiogram values were observed in derivation II, in relation to the altitude over sea level and to the animals weight, which acquires importance when a diagnose of heart abnormalities is needed from animals located at different altitudes over sea levels.

  19. Comparison of three artificial models of the MHD effect on the electrocardiogram

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    Oster, Julien; Llinares, Raul; Payne, Stephen; Tse, Zion Tsz Ho; Schmidt, Ehud Jeruham; Clifford, Gari D.

    2013-01-01

    The Electrocardiogram (ECG) is often acquired during Magnetic Resonance Imaging (MRI) for both image acquisition synchronisation with heart activity and patient monitoring to alert for life-threatening events. Accurate ECG analysis is mandatory for cutting-edge applications, such as MRI guided interventions. Nevertheless, the majority of the clinical analysis of ECG acquired inside MRI is made difficult by the superposition of a voltage called the MagnetoHydroDynamic (MHD) effect. MHD is induced by the flow of electrically charged particles in the blood perpendicular to the static magnetic field, which creates a potential of the order of magnitude of the ECG and temporally coincident with the repolatisation period. In this study, a new MHD model is proposed which is an extension of several existing models and incorporates MRI-based blood flow measurements made across the aortic arch. The model is extended to several cardiac cycles to allow the simulation of a realistic ECG acquisition during MRI examination and the quality assessment of MHD suppression techniques. A comparison of two existing models is made with our new model and with an estimate of the MHD voltage observed during a real MRI scan. Results indicate a good agreement between our proposed model and the estimated MHD for most leads, although there are clearly some descrepencies with the observed signal which are likely to be due to remaining deficiencies in the model. However, the results demonstrate that our new model provides a closer approximation to observed MHD effects and a better depiction of the complexity of the MHD effect compared to the previously published models. The source code will be made freely available under and open source license to facilitate collaboration and allow more rapid development of more accurate models of the MHD effect. PMID:24761753

  20. An Energy-Efficient Algorithm for Wearable Electrocardiogram Signal Processing in Ubiquitous Healthcare Applications

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    Ali Hassan Sodhro

    2018-03-01

    Full Text Available Rapid progress and emerging trends in miniaturized medical devices have enabled the un-obtrusive monitoring of physiological signals and daily activities of everyone’s life in a prominent and pervasive manner. Due to the power-constrained nature of conventional wearable sensor devices during ubiquitous sensing (US, energy-efficiency has become one of the highly demanding and debatable issues in healthcare. This paper develops a single chip-based wearable wireless electrocardiogram (ECG monitoring system by adopting analog front end (AFE chip model ADS1292R from Texas Instruments. The developed chip collects real-time ECG data with two adopted channels for continuous monitoring of human heart activity. Then, these two channels and the AFE are built into a right leg drive right leg drive (RLD driver circuit with lead-off detection and medical graded test signal. Human ECG data was collected at 60 beats per minute (BPM to 120 BPM with 60 Hz noise and considered throughout the experimental set-up. Moreover, notch filter (cutoff frequency 60 Hz, high-pass filter (cutoff frequency 0.67 Hz, and low-pass filter (cutoff frequency 100 Hz with cut-off frequencies of 60 Hz, 0.67 Hz, and 100 Hz, respectively, were designed with bilinear transformation for rectifying the power-line noise and artifacts while extracting real-time ECG signals. Finally, a transmission power control-based energy-efficient (ETPC algorithm is proposed, implemented on the hardware and then compared with the several conventional TPC methods. Experimental results reveal that our developed chip collects real-time ECG data efficiently, and the proposed ETPC algorithm achieves higher energy savings of 35.5% with a slightly larger packet loss ratio (PLR as compared to conventional TPC (e.g., constant TPC, Gao’s, and Xiao’s methods.

  1. The value of the 12-lead electrocardiogram in localizing the scar in non-ischaemic cardiomyopathy.

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    Oloriz, Teresa; Wellens, Hein J J; Santagostino, Giulia; Trevisi, Nicola; Silberbauer, John; Peretto, Giovanni; Maccabelli, Giuseppe; Della Bella, Paolo

    2016-12-01

    Patients with non-ischaemic cardiomyopathy (NICM) and ventricular tachycardia can be categorized as anteroseptal (AS) or inferolateral (IL) scar sub-types based on imaging and voltage mapping studies. The aim of this study was to correlate the baseline electrocardiogram (ECG) with endo-epicardial voltage maps created during ablation procedures and identify the ECG characteristics that may help to distinguish the scar as AS or IL. We assessed 108 baseline ECGs; 72 patients fulfilled criteria for dilated cardiomyopathy whereas 36 showed minimal structural abnormalities. Based on the unipolar low-voltage distribution, the scar pattern was classified as predominantly AS (n = 59) or IL (n = 49). Three ECG criteria (PR interval 230 ms or QRS > 170 ms or an r ≤ 0.3 mV in V3 having 92 and 81% of sensitivity and specificity, respectively, in predicting AS scar pattern. A significant negative correlation was found between the extension of the endocardial unipolar low voltage area and left ventricular EF (r s = -0.719, P < 0.001). The extent of endocardial AS unipolar low voltage was correlated with PR interval and QRS duration (r s = 0.583 and r s = 0.680, P < 0.001, respectively) and the IL epicardial unipolar low voltage with the mean voltage of the limb leads (r s = -0.639, P < 0.001). Baseline ECG features are well correlated with the distribution of unipolar voltage abnormalities in NICM and may help to predict the location of scar in this population. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  2. Features of electrocardiogram in patients with stenosis of the proximal right coronary artery.

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    Koh, Moo Seong; Lee, Jae Hoon; Jeong, Jin Woo; Chung, Jun Young

    2017-03-01

    Prediction of lesions of the proximal right coronary artery (pRCA) through electrocardiogram (ECG) is very important because pRCA occlusion has many complications and a high mortality rate, which has frequently been related with right ventricular infarction. The purpose of this study was to devise a screening tool that takes into account multiple leads from a 12-lead ECG to predict the pRCA lesion. A hundred and fifty-eight patients who were diagnosed as acute coronary syndrome and had a pure lesion of RCA or left circumf lex artery (LCX) by ECGs and angiographic findings were enrolled retrospectively. Forty-eight patients with a pure pRCA occlusion were compared to a control group of 110 patients who were diagnosed as having either a pure mid to distal RCA lesion (57 patients) or a pure LCX lesion (53 patients). ECGs of patients in the pRCA group showed more prominent ST depression in lead I ( p = 0.001) and ST elevation in V1 ( p = 0.002) than in the control group. The combination of ST depression (≤ 0 mm) in I and ST elevation (> 0.5 mm) in V1 was the best diagnostic tool (area under the curve, 0.84). ST changes in leads V1 and I allow more accurate prediction of pRCA occlusion than other criteria, such as the difference between ST elevation of leads II and III or vector direction and amplitude. These variables could help to screen for right ventricular infarction before performing reverse ECG and predicting prognosis.

  3. Ameliorative Effect of Vitamin E on Electrocardiogram of Rabbits Exposed to Cadmium Chloride

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    Baraa Najim Al-Okaily

    2013-02-01

    Full Text Available This study was designed to study the effect of cadmium as an oxidant agent on electrocardiogram(ECG component and the possible preventive role of vitamin E on deleterious effects of cadmium in adult male rabbits. Twenty adult male rabbits were divided randomly into 4 equal groups (5 animals /group and treated daily for 84 days. The first group were received ordinary tap water and serve as control (C; the second group (T1 received ad libitum supply of drinking water containing (50ppb cadmium chloride; the third group T2 received (50ppb of cadmium chloride in drinking water, in addition to intubation of vitamin E (40mg/Kg B.W. orally, while the fourth group (T3 were intubated daily with 40mg/Kg B.W of vitamin E. Fasting blood samples were collected at 0, 21, 42, 63 and 84 days of the experiment to determine serum calcium concentration . The ECG was also recorded in all groups at the same interval of the experiment. The results revealed that administration of 50 ppb CdCl2 in drinking water (T1 group for 84 days caused a significant decrease(p0.05 differences in this parameter as compared to control and other groups. Analysis of ECG in Cadmium treated group (T1 showed significant (p0.05 differences in ECG waves analysis. In conclusion, Cadmium effect on electrical conduction of heart was represented by abnormality in some of ECG component as well as the protective role of vitamin E as antioxidant in the cardiovascular system was also confirmed.

  4. Clinical evaluation of the use of an intracardiac electrocardiogram to guide the tip positioning of peripherally inserted central catheters.

    Science.gov (United States)

    Zhao, Ruiyi; Chen, Chunfang; Jin, Jingfen; Sharma, Komal; Jiang, Nan; Shentu, Yingqin; Wang, Xingang

    2016-06-01

    The use of peripherally inserted central catheters (PICCs) provides important central venous accesses for clinical treatments, tests and monitoring. Compared with the traditional methods, intracardiac electrocardiogram (ECG)-guided method has the potential to guide more accurate tip positioning of PICCs. This study aimed to clinically evaluate the effectiveness of an intracardiac ECG to guide the tip positioning by monitoring characteristic P-wave changes. In this study, eligible patients enrolled September 2011 to May 2012 according to the inclusion and exclusion criteria received the catheterization monitored by intracardiac ECG. Then chest radiography was performed to check the catheter position. The results revealed that, with 117 eligible patients, all bar one patient who died (n = 116) completed the study, including 60 males and 56 females aged 51.2 ± 15.1 years. Most (n = 113, > 97%) had characteristic P-wave changes. The intracardiac ECG-guided positioning procedure achieved correct placement for 112 patients (96.56%), demonstrating 99.12% sensitivity and 100% specificity. In conclusion, the intracardiac ECG can be a promising technique to guide tip positioning of PICCs. However, since the sample size in this study is limited, more experience and further study during clinical practice are needed to demonstrate achievement of optimal catheterization outcomes. © 2015 John Wiley & Sons Australia, Ltd.

  5. A comparison of conductive textile-based and silver/silver chloride gel electrodes in exercise electrocardiogram recordings.

    Science.gov (United States)

    Marozas, Vaidotas; Petrenas, Andrius; Daukantas, Saulius; Lukosevicius, Arunas

    2011-01-01

    The goal of this study was to compare disposable silver/silver chloride and reusable conductive textile-based electrodes in electrocardiogram (ECG) signal monitoring during physical activity. The reusable electrodes were produced using thin silver-plated nylon 117/17 2-ply conductive thread (Statex Productions & Vertriebs GmbH, Bremen, Germany) sewed with a sewing machine on a chest belt. The disposable and reusable electrodes were compared in vivo according to ECG signal baseline drift, broadband electrode noise properties, and influence of electrode area to ECG signal morphology and frequency content. Twelve volunteers were included in this study. Electroconductive textile-based ECG electrodes produce significantly more noise in a very low frequency band (0-0.67 Hz) and not significantly less of broadband noise (0-250 Hz) than disposable silver/silver chloride electrodes. Decreasing area of textile electrodes decreases fidelity of registered ECG signals at low frequencies. Textile electrodes having adequate area can be used in more applications than only R-R interval monitoring. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Predictable and reliable ECG monitoring over IEEE 802.11 WLANs within a hospital.

    Science.gov (United States)

    Park, Juyoung; Kang, Kyungtae

    2014-09-01

    Telecardiology provides mobility for patients who require constant electrocardiogram (ECG) monitoring. However, its safety is dependent on the predictability and robustness of data delivery, which must overcome errors in the wireless channel through which the ECG data are transmitted. We report here a framework that can be used to gauge the applicability of IEEE 802.11 wireless local area network (WLAN) technology to ECG monitoring systems in terms of delay constraints and transmission reliability. For this purpose, a medical-grade WLAN architecture achieved predictable delay through the combination of a medium access control mechanism based on the point coordination function provided by IEEE 802.11 and an error control scheme based on Reed-Solomon coding and block interleaving. The size of the jitter buffer needed was determined by this architecture to avoid service dropout caused by buffer underrun, through analysis of variations in transmission delay. Finally, we assessed this architecture in terms of service latency and reliability by modeling the transmission of uncompressed two-lead electrocardiogram data from the MIT-BIH Arrhythmia Database and highlight the applicability of this wireless technology to telecardiology.

  7. Assessment of Reproducibility – Automated and Digital Caliper ECG Measurement in the Framingham Heart Study

    Science.gov (United States)

    Burke, Gordon M.; Wang, Na; Blease, Sue; Levy, Daniel; Magnani, Jared W.

    2014-01-01

    Background Digitized electrocardiography permits the rapid, automated quantification of electrocardiograms (ECGs) for analysis. Community- and population-based studies have increasingly integrated such data. Assessing the reproducibility of automated ECG measures with manual measures is a critical step in preparation for using automated measures for research purposes. We recently established an ECG repository of digitally recorded ECGs for the Framingham Heart Study and we sought to assess the reproducibility of automated and manual measures. Methods We selected 185 digitally recorded ECGs from routine visits of Framingham Heart Study participants spanning from 1986 to 2012. We selected the following ECG measures for their relevance to clinical and epidemiologic research: P wave duration, P wave amplitude, and PR interval in lead II; QRS duration and R wave amplitude in lead V6; and QT interval in lead V5. We obtained automated values for each waveform, and used a digital caliper for manual measurements. Digital caliper measurements were repeated in a subset (n=81) of the samples for intrarater assessment. Results We calculated the intraclass correlation coefficient (ICC) values for the interrater and intrarater assessments. P wave duration had the lowest interrater ICC (r=0.46) and lowest intrarater ICC (r=0.57). R wave amplitude had the highest interrater and intrarater ICC (r=0.98) indicating excellent reproducibility. The remaining measures had interrater and intrarater ICCs of r≥0.81. Conclusions The interrater reproducibility findings for P wave amplitude, PR interval, QT interval, QRS duration, and R wave amplitude were excellent. In contrast, the reproducibility of P wave duration was more modest. These findings indicate high reproducibility of most automated and manual ECG measurements. PMID:24792985

  8. Assessment of reproducibility--automated and digital caliper ECG measurement in the Framingham Heart Study.

    Science.gov (United States)

    Burke, Gordon M; Wang, Na; Blease, Sue; Levy, Daniel; Magnani, Jared W

    2014-01-01

    Digitized electrocardiography permits the rapid, automated quantification of electrocardiograms (ECGs) for analysis. Community- and population-based studies have increasingly integrated such data. Assessing the reproducibility of automated ECG measures with manual measures is a critical step in preparation for using automated measures for research purposes. We recently established an ECG repository of digitally recorded ECGs for the Framingham Heart Study and we sought to assess the reproducibility of automated and manual measures. We selected 185 digitally recorded ECGs from routine visits of Framingham Heart Study participants spanning from 1986 to 2012. We selected the following ECG measures for their relevance to clinical and epidemiologic research: P wave duration, P wave amplitude, and PR interval in lead II; QRS duration and R wave amplitude in lead V6; and QT interval in lead V5. We obtained automated values for each waveform, and used a digital caliper for manual measurements. Digital caliper measurements were repeated in a subset (n=81) of the samples for intrarater assessment. We calculated the intraclass correlation coefficient (ICC) values for the interrater and intrarater assessments. P wave duration had the lowest interrater ICC (r=0.46) and lowest intrarater ICC (r=0.57). R wave amplitude had the highest interrater and intrarater ICC (r=0.98) indicating excellent reproducibility. The remaining measures had interrater and intrarater ICCs of r≥0.81. The interrater reproducibility findings for P wave amplitude, PR interval, QT interval, QRS duration, and R wave amplitude were excellent. In contrast, the reproducibility of P wave duration was more modest. These findings indicate high reproducibility of most automated and manual ECG measurements. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Feasibility of Using Mobile ECG Recording Technology to Detect Atrial Fibrillation in Low-Resource Settings.

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    Evans, Grahame F; Shirk, Arianna; Muturi, Peter; Soliman, Elsayed Z

    2017-12-01

    Screening for atrial fibrillation (AF), a major risk factor for stroke that is on the rise in Africa, is becoming increasingly critical. This study sought to examine the feasibility of using mobile electrocardiogram (ECG) recording technology to detect AF. In this prospective observational study, we used a mobile ECG recorder to screen 50 African adults (66% women; mean age 54.3 ± 20.5 years) attending Kijabe Hospital (Kijabe, Kenya). Five hospital health providers involved in this study's data collection process also completed a self-administered survey to obtain information on their access to the Internet and mobile devices, both factors necessary to implement ECG mobile technology. Outcome measures included feasibility (completion of the study and recruitment of the patients on the planned study time frame) and the yield of the screening by the mobile ECG technology (ability to detect previously undiagnosed AF). Patients were recruited in a 2-week period as planned; only 1 of the 51 patients approached refused to participate (98% acceptance rate). All of the 50 patients who agreed to participate completed the test and produced readable ECGs (100% study completion rate). ECG tracings of 4 of the 50 patients who completed the study showed AF (8% AF yield), and none had been previously diagnosed with AF. When asked about continuous access to Internet and personal mobile devices, almost all of the health care providers surveyed answered affirmatively. Using mobile ECG technology in screening for AF in low-resource settings is feasible, and can detect a significant proportion of AF cases that will otherwise go undiagnosed. Further study is needed to examine the cost-effectiveness of this approach for detection of AF and its effect on reducing the risk of stroke in developing countries. Copyright © 2016 World Heart Federation (Geneva). Published by Elsevier B.V. All rights reserved.

  10. Transform Domain Robust Variable Step Size Griffiths' Adaptive Algorithm for Noise Cancellation in ECG

    Science.gov (United States)

    Hegde, Veena; Deekshit, Ravishankar; Satyanarayana, P. S.

    2011-12-01

    The electrocardiogram (ECG) is widely used for diagnosis of heart diseases. Good quality of ECG is utilized by physicians for interpretation and identification of physiological and pathological phenomena. However, in real situations, ECG recordings are often corrupted by artifacts or noise. Noise severely limits the utility of the recorded ECG and thus needs to be removed, for better clinical evaluation. In the present paper a new noise cancellation technique is proposed for removal of random noise like muscle artifact from ECG signal. A transform domain robust variable step size Griffiths' LMS algorithm (TVGLMS) is proposed for noise cancellation. For the TVGLMS, the robust variable step size has been achieved by using the Griffiths' gradient which uses cross-correlation between the desired signal contaminated with observation or random noise and the input. The algorithm is discrete cosine transform (DCT) based and uses symmetric property of the signal to represent the signal in frequency domain with lesser number of frequency coefficients when compared to that of discrete Fourier transform (DFT). The algorithm is implemented for adaptive line enhancer (ALE) filter which extracts the ECG signal in a noisy environment using LMS filter adaptation. The proposed algorithm is found to have better convergence error/misadjustment when compared to that of ordinary transform domain LMS (TLMS) algorithm, both in the presence of white/colored observation noise. The reduction in convergence error achieved by the new algorithm with desired signal decomposition is found to be lower than that obtained without decomposition. The experimental results indicate that the proposed method is better than traditional adaptive filter using LMS algorithm in the aspects of retaining geometrical characteristics of ECG signal.

  11. Is an Abnormal ECG Just the Tip of the ICE-berg? Examining the Utility of Electrocardiography in Detecting Methamphetamine-Induced Cardiac Pathology.

    Science.gov (United States)

    Paratz, Elizabeth D; Zhao, Jessie; Sherwen, Amanda K; Scarlato, Rose-Marie; MacIsaac, Andrew I

    2017-07-01

    Methamphetamine use is escalating in Australia and New Zealand, with increasing emergency department attendance and mortality. Cardiac complications play a large role in methamphetamine-related mortality, and it would be informative to assess the frequency of abnormal electrocardiograms (ECGs) amongst methamphetamine users. To determine the frequency and severity of ECG abnormalities amongst methamphetamine users compared to a control group. We conducted a retrospective cohort analysis on 212 patients admitted to a tertiary hospital (106 patients with methamphetamine use, 106 age and gender-matched control patients). Electrocardiograms were analysed according to American College of Cardiology guidelines. Mean age was 33.4 years, with 73.6% male gender, with no significant differences between groups in smoking status, ECG indication, or coronary angiography rates. Methamphetamine users were more likely to have psychiatric admissions (22.6% vs 1.9%, pECG abnormalities were significantly more common (71.7% vs 32.1%, pECGs should be performed in all methamphetamine users who present to hospital. Methamphetamine users with abnormal ECGs should undergo further cardiac investigations. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). All rights reserved.

  12. Adaptive Dictionary Reconstruction for Compressed Sensing of ECG Signals.

    Science.gov (United States)

    Craven, Darren; McGinley, Brian; Kilmartin, Liam; Glavin, Martin; Jones, Edward

    2017-05-01

    This paper proposes a novel adaptive dictionary (AD) reconstruction scheme to improve the performance of compressed sensing (CS) with electrocardiogram signals (ECG). The method is based on the use of multiple dictionaries, created using dictionary learning (DL) techniques for CS signal reconstruction. The modified reconstruction framework is a two-stage process that leverages information about the signal from an initial signal reconstruction stage. By identifying whether a QRS complex is present and if so, determining a location estimate of the QRS, the most appropriate dictionary is selected and a second stage more refined signal reconstruction can be obtained. The performance of the proposed algorithm is compared with state-of-the-art CS implementations in the literature, as well as the set partitioning in hierarchical trees (SPIHT) wavelet-based lossy compression algorithm. The results indicate that the proposed reconstruction scheme outperforms all existing CS implementations in terms of signal fidelity at each compression ratio tested. The performance of the proposed approach also compares favorably with SPIHT in terms of signal reconstruction quality. Furthermore, an analysis of the overall power consumption of the proposed ECG compression framework as would be used in a body area network (BAN) demonstrates positive results for the proposed CS approach when compared with existing CS techniques and SPIHT.

  13. A Mobile Device System for Early Warning of ECG Anomalies

    Directory of Open Access Journals (Sweden)

    Adam Szczepański

    2014-06-01

    Full Text Available With the rapid increase in computational power of mobile devices the amount of ambient intelligence-based smart environment systems has increased greatly in recent years. A proposition of such a solution is described in this paper, namely real time monitoring of an electrocardiogram (ECG signal during everyday activities for identification of life threatening situations. The paper, being both research and review, describes previous work of the authors, current state of the art in the context of the authors’ work and the proposed aforementioned system. Although parts of the solution were described in earlier publications of the authors, the whole concept is presented completely for the first time along with the prototype implementation on mobile device—a Windows 8 tablet with Modern UI. The system has three main purposes. The first goal is the detection of sudden rapid cardiac malfunctions and informing the people in the patient’s surroundings, family and friends and the nearest emergency station about the deteriorating health of the monitored person. The second goal is a monitoring of ECG signals under non-clinical conditions to detect anomalies that are typically not found during diagnostic tests. The third goal is to register and analyze repeatable, long-term disturbances in the regular signal and finding their patterns.

  14. Electrocardiogram transmission - The state of the art.

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    Firstenberg, A.; Huston, S. W.; Olsen, D. E.; Hahn, P. M.

    1971-01-01

    A comparative analysis of available clinical EKG telemetry systems was conducted. Although present day electrocardiogram diagnosis requires a high degree of measurement accuracy, there exists wide variations in the performance characteristics of the various telemeters marketed today necessitating careful consideration of specifications prior to procurement. The authors have endeavored to provide the physicians with a clear understanding, in terms of the effects on the electrocardiogram, of the factors he must evaluate in order to ensure high fidelity EKG reproduction. A tabulation of comparative parameter values for each unit obtained from manufacturers' specifications and substantiated by standardized performance tests conducted in our laboratory is presented.

  15. New methodologies for measuring Brugada ECG patterns cannot differentiate the ECG pattern of Brugada syndrome from Brugada phenocopy.

    Science.gov (United States)

    Gottschalk, Byron H; Garcia-Niebla, Javier; Anselm, Daniel D; Jaidka, Atul; De Luna, Antoni Bayés; Baranchuk, Adrian

    2016-01-01

    Brugada phenocopies (BrP) are clinical entities characterized by ECG patterns that are identical to true Brugada syndrome (BrS), but are elicited by various clinical circumstances. A recent study demonstrated that the patterns of BrP and BrS are indistinguishable under the naked eye, thereby validating the concept that the patterns are identical. The aim of our study was to determine whether recently developed ECG criteria would allow for discrimination between type-2 BrS ECG pattern and type-2 BrP ECG pattern. Ten ECGs from confirmed BrS (aborted sudden death, transformation into type 1 upon sodium channel blocking test and/or ventricular arrhythmias, positive genetics) cases and 9 ECGs from confirmed BrP were included in the study. Surface 12-lead ECGs were scanned, saved in JPEG format for blind measurement of two values: (i) β-angle; and (ii) the base of the triangle. Cut-off values of ≥58° for the β-angle and ≥4mm for the base of the triangle were used to determine the BrS ECG pattern. Mean values for the β-angle in leads V1 and V2 were 66.7±25.5 and 55.4±28.1 for BrS and 54.1±26.5 and 43.1±16.1 for BrP respectively (p=NS). Mean values for the base of the triangle in V1 and V2 were 7.5±3.9 and 5.7±3.9 for BrS and 5.6±3.2 and 4.7±2.7 for BrP respectively (p=NS). The β-angle had a sensitivity of 60%, specificity of 78% (LR+ 2.7, LR- 0.5). The base of the triangle had a sensitivity of 80%, specificity of 40% (LR+ 1.4, LR- 0.5). New ECG criteria presented relatively low sensitivity and specificity, positive and negative predictive values to discriminate between BrS and BrP ECG patterns, providing further evidence that the two patterns are identical. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Vectorcardiographic diagnostic & prognostic information derived from the 12-lead electrocardiogram: Historical review and clinical perspective.

    Science.gov (United States)

    Man, Sumche; Maan, Arie C; Schalij, Martin J; Swenne, Cees A

    2015-01-01

    In the course of time, electrocardiography has assumed several modalities with varying electrode numbers, electrode positions and lead systems. 12-lead electrocardiography and 3-lead vectorcardiography have become particularly popular. These modalities developed in parallel through the mid-twentieth century. In the same time interval, the physical concepts underlying electrocardiography were defined and worked out. In particular, the vector concept (heart vector, lead vector, volume conductor) appeared to be essential to understanding the manifestations of electrical heart activity, both in the 12-lead electrocardiogram (ECG) and in the 3-lead vectorcardiogram (VCG). Not universally appreciated in the clinic, the vectorcardiogram, and with it the vector concept, went out of use. A revival of vectorcardiography started in the 90's, when VCGs were mathematically synthesized from standard 12-lead ECGs. This facilitated combined electrocardiography and vectorcardiography without the need for a special recording system. This paper gives an overview of these historical developments, elaborates on the vector concept and seeks to define where VCG analysis/interpretation can add diagnostic/prognostic value to conventional 12-lead ECG analysis. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Human Age Recognition by Electrocardiogram Signal Based on Artificial Neural Network

    Science.gov (United States)

    Dasgupta, Hirak

    2016-12-01

    The objective of this work is to make a neural network function approximation model to detect human age from the electrocardiogram (ECG) signal. The input vectors of the neural network are the Katz fractal dimension of the ECG signal, frequencies in the QRS complex, male or female (represented by numeric constant) and the average of successive R-R peak distance of a particular ECG signal. The QRS complex has been detected by short time Fourier transform algorithm. The successive R peak has been detected by, first cutting the signal into periods by auto-correlation method and then finding the absolute of the highest point in each period. The neural network used in this problem consists of two layers, with Sigmoid neuron in the input and linear neuron in the output layer. The result shows the mean of errors as -0.49, 1.03, 0.79 years and the standard deviation of errors as 1.81, 1.77, 2.70 years during training, cross validation and testing with unknown data sets, respectively.

  18. Utility of the exercise electrocardiogram testing in sudden cardiac death risk stratification.

    Science.gov (United States)

    Refaat, Marwan M; Hotait, Mostafa; Tseng, Zian H

    2014-07-01

    Sudden cardiac death (SCD) remains a major public health problem. Current established criteria identifying those at risk of sudden arrhythmic death, and likely to benefit from implantable cardioverter defibrillators (ICDs), are neither sensitive nor specific. Exercise electrocardiogram (ECG) testing was traditionally used for information concerning patients' symptoms, exercise capacity, cardiovascular function, myocardial ischemia detection, and hemodynamic responses during activity in patients with hypertrophic cardiomyopathy. We conducted a systematic review of MEDLINE on the utility of exercise ECG testing in SCD risk stratification. Exercise testing can unmask suspected primary electrical diseases in certain patients (catecholaminergic polymorphic ventricular tachycardia or concealed long QT syndrome) and can be effectively utilized to risk stratify patients at an increased (such as early repolarization syndrome and Brugada syndrome) or decreased risk of SCD, such as the loss of preexcitation on exercise testing in asymptomatic Wolff-Parkinson-White syndrome. Exercise ECG testing helps in SCD risk stratification in patients with and without arrhythmogenic hereditary syndromes. © 2014 Wiley Periodicals, Inc.

  19. A new technique for simultaneous monitoring of electrocardiogram and walking cadence

    Science.gov (United States)

    Hausdorff, J. M.; Forman, D. E.; Pilgrim, D. M.; Rigney, D. R.; Wei, J. Y.; Goldberger, A. L. (Principal Investigator)

    1992-01-01

    A new technique for simultaneously recording continuous electrocardiographic (ECG) data and walking step rate (cadence) is described. The ECG and gait signals are recorded on 2 channels of an ambulatory Holter monitor. Footfall is detected using ultrathin, force-sensitive foot switches and is frequency modulated. The footfall signal provides an indication of the subject's activity (walking or standing), as well as the instantaneous walking rate. Twenty-three young and elderly subjects were studied to demonstrate the use of this ECG and gait recorder. High-quality gait signals were obtained in all subjects, and the effects of walking on the electrocardiogram were assessed. Initial investigation revealed the following findings: (1) Although walking rates were similar in young and elderly subjects, the elderly had both decreased heart rate (HR) variability (p elderly subjects with no known cardiac disease had HR and cadence variability similar to those of the young, whereas elderly subjects with history of congestive heart failure were among those with the lowest HR variability and the highest cadence variability. (3) Low-frequency (approximately equal to 0.1 Hz) HR oscillations (frequently observed during standing) persisted during walking in all young subjects. (4) In some subjects, both step rate and HR oscillated at the same low frequency (approximately equal to 0.1 Hz) previously identified with autonomic control of the baroreflex.(ABSTRACT TRUNCATED AT 250 WORDS).

  20. An obstructive sleep apnea detection approach using kernel density classification based on single-lead electrocardiogram.

    Science.gov (United States)

    Chen, Lili; Zhang, Xi; Wang, Hui

    2015-05-01

    Obstructive sleep apnea (OSA) is a common sleep disorder that often remains undiagnosed, leading to an increased risk of developing cardiovascular diseases. Polysomnogram (PSG) is currently used as a golden standard for screening OSA. However, because it is time consuming, expensive and causes discomfort, alternative techniques based on a reduced set of physiological signals are proposed to solve this problem. This study proposes a convenient non-parametric kernel density-based approach for detection of OSA using single-lead electrocardiogram (ECG) recordings. Selected physiologically interpretable features are extracted from segmented RR intervals, which are obtained from ECG signals. These features are fed into the kernel density classifier to detect apnea event and bandwidths for density of each class (normal or apnea) are automatically chosen through an iterative bandwidth selection algorithm. To validate the proposed approach, RR intervals are extracted from ECG signals of 35 subjects obtained from a sleep apnea database ( http://physionet.org/cgi-bin/atm/ATM ). The results indicate that the kernel density classifier, with two features for apnea event detection, achieves a mean accuracy of 82.07 %, with mean sensitivity of 83.23 % and mean specificity of 80.24 %. Compared with other existing methods, the proposed kernel density approach achieves a comparably good performance but by using fewer features without significantly losing discriminant power, which indicates that it could be widely used for home-based screening or diagnosis of OSA.

  1. Fusion Framework for Emotional Electrocardiogram and Galvanic Skin Response Recognition: Applying Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Atefeh Goshvarpour

    2016-09-01

    Full Text Available Introduction To extract and combine information from different modalities, fusion techniques are commonly applied to promote system performance. In this study, we aimed to examine the effectiveness of fusion techniques in emotion recognition. Materials and Methods Electrocardiogram (ECG and galvanic skin responses (GSR of 11 healthy female students (mean age: 22.73±1.68 years were collected while the subjects were listening to emotional music clips. For multi-resolution analysis of signals, wavelet transform (Coiflets 5 at level 14 was used. Moreover, a novel feature-level fusion method was employed, in which low-frequency sub-band coefficients of GSR signals and high-frequency sub-band coefficients of ECG signals were fused to reconstruct a new feature. To reduce the dimensionality of the feature vector, the absolute value of some statistical indices was calculated and considered as input of PNN classifier. To describe emotions, two-dimensional models (four quadrants of valence and arousal dimensions, valence-based emotional states, and emotional arousal were applied. Results The highest recognition rates were obtained from sigma=0.01. Mean classification rate of 100% was achieved through applying the proposed fusion methodology. However, the accuracy rates of 97.90% and 97.20% were attained for GSR and ECG signals, respectively. Conclusion Compared to the previously published articles in the field of emotion recognition using musical stimuli, promising results were obtained through application of the proposed methodology.

  2. Real-time electrocardiogram transmission from Mount Everest during continued ascent.

    Science.gov (United States)

    Kao, Wei-Fong; Huang, Jyh-How; Kuo, Terry B J; Chang, Po-Lun; Chang, Wen-Chen; Chan, Kuo-Hung; Liu, Wen-Hsiung; Wang, Shih-Hao; Su, Tzu-Yao; Chiang, Hsiu-chen; Chen, Jin-Jong

    2013-01-01

    The feasibility of a real-time electrocardiogram (ECG) transmission via satellite phone from Mount Everest to determine a climber's suitability for continued ascent was examined. Four Taiwanese climbers were enrolled in the 2009 Mount Everest summit program. Physiological measurements were taken at base camp (5300 m), camp 2 (6400 m), camp 3 (7100 m), and camp 4 (7950 m) 1 hour after arrival and following a 10 minute rest period. A total of 3 out of 4 climbers were able to summit Mount Everest successfully. Overall, ECG and global positioning system (GPS) coordinates of climbers were transmitted in real-time via satellite phone successfully from base camp, camp 2, camp 3, and camp 4. At each camp, Resting Heart Rate (RHR) was transmitted and recorded: base camp (54-113 bpm), camp 2 (94-130 bpm), camp 3 (98-115 bpm), and camp 4 (93-111 bpm). Real-time ECG and GPS coordinate transmission via satellite phone is feasible for climbers on Mount Everest. Real-time RHR data can be used to evaluate a climber's physiological capacity to continue an ascent and to summit.

  3. Real-time electrocardiogram transmission from Mount Everest during continued ascent.

    Directory of Open Access Journals (Sweden)

    Wei-Fong Kao

    Full Text Available The feasibility of a real-time electrocardiogram (ECG transmission via satellite phone from Mount Everest to determine a climber's suitability for continued ascent was examined. Four Taiwanese climbers were enrolled in the 2009 Mount Everest summit program. Physiological measurements were taken at base camp (5300 m, camp 2 (6400 m, camp 3 (7100 m, and camp 4 (7950 m 1 hour after arrival and following a 10 minute rest period. A total of 3 out of 4 climbers were able to summit Mount Everest successfully. Overall, ECG and global positioning system (GPS coordinates of climbers were transmitted in real-time via satellite phone successfully from base camp, camp 2, camp 3, and camp 4. At each camp, Resting Heart Rate (RHR was transmitted and recorded: base camp (54-113 bpm, camp 2 (94-130 bpm, camp 3 (98-115 bpm, and camp 4 (93-111 bpm. Real-time ECG and GPS coordinate transmission via satellite phone is feasible for climbers on Mount Everest. Real-time RHR data can be used to evaluate a climber's physiological capacity to continue an ascent and to summit.

  4. ECG changes in epilepsy patients

    DEFF Research Database (Denmark)

    Tigaran, S; Rasmussen, V; Dam, M

    1997-01-01

    To investigate the frequency of ECG abnormalities suggestive of myocardial ischaemia in patients with severe drug resistant epilepsy and without any indication of previous cardiac disease, assuming that these changes may be of significance for the group of epileptic patients with sudden unexpected...

  5. 'Brugada ECG' elicited by imipramine overdose

    NARCIS (Netherlands)

    van den Berg, M. P.; Tulleken, J. E.; Wilde, A. A. M.

    2004-01-01

    The ECG hallmark of the Brugada syndrome is ST-segment elevation in the right precordial leads. However, a 'Brugada ECG' may also occasionally be caused by other conditions. We report a case of a Brugada ECG due to an overdose of imipramine, a tricyclic antidepressant. The patient, a 66-year-old

  6. Friend or Foe? Flipped Classroom for Undergraduate Electrocardiogram Learning: a Randomized Controlled Study.

    Science.gov (United States)

    Rui, Zeng; Lian-Rui, Xiang; Rong-Zheng, Yue; Jing, Zeng; Xue-Hong, Wan; Chuan, Zuo

    2017-03-07

    Interpreting an electrocardiogram (ECG) is not only one of the most important parts of clinical diagnostics but also one of the most difficult topics to teach and learn. In order to enable medical students to master ECG interpretation skills in a limited teaching period, the flipped teaching method has been recommended by previous research to improve teaching effect on undergraduate ECG learning. A randomized controlled trial for ECG learning was conducted, involving 181 junior-year medical undergraduates using a flipped classroom as an experimental intervention, compared with Lecture-Based Learning (LBL) as a control group. All participants took an examination one week after the intervention by analysing 20 ECGs from actual clinical cases and submitting their ECG reports. A self-administered questionnaire was also used to evaluate the students' attitudes, total learning time, and conditions under each teaching method. The students in the experimental group scored significantly higher than the control group (8.72 ± 1.01 vs 8.03 ± 1.01, t = 4.549, P = 0.000) on ECG interpretation. The vast majority of the students in the flipped classroom group held positive attitudes toward the flipped classroom method and also supported LBL. There was no significant difference (4.07 ± 0.96 vs 4.16 ± 0.89, Z = - 0.948, P = 0.343) between the groups. Prior to class, the students in the flipped class group devoted significantly more time than those in the control group (42.33 ± 22.19 vs 30.55 ± 10.15, t = 4.586, P = 0.000), whereas after class, the time spent by the two groups were not significantly different (56.50 ± 46.80 vs 54.62 ± 31.77, t = 0.317, P = 0.752). Flipped classroom teaching can improve medical students' interest in learning and their self-learning abilities. It is an effective teaching model that needs to be further studied and promoted.

  7. Position difference regularity of corresponding R-wave peaks for maternal ECG components from different abdominal points

    International Nuclear Information System (INIS)

    Zhang Jie-Min; Liu Hong-Xing; Huang Xiao-Lin; Si Jun-Feng; Guan Qun; Tang Li-Ming; Liu Tie-Bing

    2014-01-01

    We collected 343 groups of abdominal electrocardiogram (ECG) data from 78 pregnant women and deleted the channels unable for experts to determine R-wave peaks from them; then, based on these filtered data, the statistics of position difference of corresponding R-wave peaks for different maternal ECG components from different points were studied. The resultant statistics showed the regularity that the position difference of corresponding maternal R-wave peaks between different abdominal points does not exceed the range of 30 ms. The regularity was also proved using the fECG data from MIT—BIH PhysioBank. Additionally, the paper applied the obtained regularity, the range of position differences of the corresponding maternal R-wave peaks, to accomplish the automatic detection of maternal R-wave peaks in the recorded all initial 343 groups of abdominal signals, including the ones with the largest fetal ECG components, and all 55 groups of ECG data from MIT—BIH PhysioBank, achieving the successful separation of the maternal ECGs. (interdisciplinary physics and related areas of science and technology)

  8. A practical algorithm to reduce false critical ECG alarms using arterial blood pressure and/or photoplethysmogram waveforms.

    Science.gov (United States)

    Zong, Wei; Nielsen, Larry; Gross, Brian; Brea, Juan; Frassica, Joseph

    2016-08-01

    There has been a high rate of false alarms for the critical electrocardiogram (ECG) arrhythmia events in intensive care units (ICUs), from which the 'crying-wolf' syndrome may be resulted and patient safety may be jeopardized. This article presents an algorithm to reduce false critical arrhythmia alarms using arterial blood pressure (ABP) and/or photoplethysmogram (PPG) waveform features. We established long duration reference alarm datasets which consist of 573 ICU waveform-alarm records (283 for development set and 290 for test set) with total length of 551 patent days. Each record has continuous recordings of ECGs, ABP and/or PPG signals and contains one or multiple critical ECG alarms. The average length of a record is 23 h. There are totally 2408 critical ECG alarms (1414 in the development set and 994 in the test set), each of which was manually annotated by experts. The algorithm extracts ABP/PPG pulse features on a beat-by-beat basis. For each pulse, five event feature indicators (EFIs), which correspond to the five critical ECG alarms, are generated. At the time of a critical ECG alarm, the corresponding EFI values of those ABP/PPG pulses around the alarm time are checked for adjudicating (accept/reject) this alarm. The algorithm retains all (100%) the true alarms and significantly reduces the false alarms. Our results suggest that the algorithm is effective and practical on account of its real-time dynamic processing mechanism and computational efficiency.

  9. An Adaptive Particle Weighting Strategy for ECG Denoising Using Marginalized Particle Extended Kalman Filter: An Evaluation in Arrhythmia Contexts.

    Science.gov (United States)

    Hesar, Hamed Danandeh; Mohebbi, Maryam

    2017-11-01

    Model-based Bayesian frameworks have a common problem in processing electrocardiogram (ECG) signals with sudden morphological changes. This situation often happens in the case of arrhythmias where ECGs do not obey the predefined state models. To solve this problem, in this paper, a model-based Bayesian denoising framework is proposed using marginalized particle-extended Kalman filter (MP-EKF), variational mode decomposition, and a novel fuzzy-based adaptive particle weighting strategy. This strategy helps MP-EKF to perform well even when the morphology of signal does not comply with the predefined dynamic model. In addition, this strategy adapts MP-EKF's behavior to the acquired measurements in different input signal to noise ratios (SNRs). At low input SNRs, this strategy decreases the particles' trust level to the measurements while increasing their trust level to a synthetic ECG constructed with the feature parameters of ECG dynamic model. At high input SNRs, the particles' trust level to the measurements is increased and the trust level to synthetic ECG is decreased. The proposed method was evaluated on MIT-BIH normal sinus rhythm database and compared with EKF/EKS frameworks and previously proposed MP-EKF. It was also evaluated on ECG segments extracted from MIT-BIH arrhythmia database, which contained ventricular and atrial arrhythmia. The results showed that the proposed algorithm had a noticeable superiority over benchmark methods from both SNR improvement and multiscale entropy based weighted distortion (MSEWPRD) viewpoints at low input SNRs.

  10. Investigating the effect of traditional Persian music on ECG signals in young women using wavelet transform and neural networks.

    Science.gov (United States)

    Abedi, Behzad; Abbasi, Ataollah; Goshvarpour, Atefeh

    2017-05-01

    In the past few decades, several studies have reported the physiological effects of listening to music. The physiological effects of different music types on different people are different. In the present study, we aimed to examine the effects of listening to traditional Persian music on electrocardiogram (ECG) signals in young women. Twenty-two healthy females participated in this study. ECG signals were recorded under two conditions: rest and music. For each ECG signal, 20 morphological and wavelet-based features were selected. Artificial neural network (ANN) and probabilistic neural network (PNN) classifiers were used for the classification of ECG signals during and before listening to music. Collected data were separated into two data sets: train and test. Classification accuracies of 88% and 97% were achieved in train data sets using ANN and PNN, respectively. In addition, the test data set was employed for evaluating the classifiers, and classification rates of 84% and 93% were obtained using ANN and PNN, respectively. The present study investigated the effect of music on ECG signals based on wavelet transform and morphological features. The results obtained here can provide a good understanding on the effects of music on ECG signals to researchers.

  11. Application of stacked convolutional and long short-term memory network for accurate identification of CAD ECG signals.

    Science.gov (United States)

    Tan, Jen Hong; Hagiwara, Yuki; Pang, Winnie; Lim, Ivy; Oh, Shu Lih; Adam, Muhammad; Tan, Ru San; Chen, Ming; Acharya, U Rajendra

    2018-03-01

    Coronary artery disease (CAD) is the most common cause of heart disease globally. This is because there is no symptom exhibited in its initial phase until the disease progresses to an advanced stage. The electrocardiogram (ECG) is a widely accessible diagnostic tool to diagnose CAD that captures abnormal activity of the heart. However, it lacks diagnostic sensitivity. One reason is that, it is very challenging to visually interpret the ECG signal due to its very low amplitude. Hence, identification of abnormal ECG morphology by clinicians may be prone to error. Thus, it is essential to develop a software which can provide an automated and objective interpretation of the ECG signal. This paper proposes the implementation of long short-term memory (LSTM) network with convolutional neural network (CNN) to automatically diagnose CAD ECG signals accurately. Our proposed deep learning model is able to detect CAD ECG signals with a diagnostic accuracy of 99.85% with blindfold strategy. The developed prototype model is ready to be tested with an appropriate huge database before the clinical usage. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Estimation of a respiratory signal from a single-lead ECG using the 4th order central moments

    Directory of Open Access Journals (Sweden)

    Schmidt Marcus

    2015-09-01

    Full Text Available For a variety of clinical applications like magnetic resonance imaging (MRI the monitoring of vital signs is a common standard in clinical daily routine. Besides the electrocardiogram (ECG, the respiratory activity is an important vital parameter and might reveal pathological changes. Thoracic movement and the resulting impedance change between ECG electrodes enable the estimation of the respiratory signal from the ECG. This ECG-derived respiration (EDR can be used to calculate the breathing rate without the need for additional devices or monitoring modules. In this paper a new method is presented to estimate the respiratory signal from a single-lead ECG. The 4th order central moments was used to estimate the EDR signal exploiting the change of the R-wave slopes induced by respiration. This method was compared with two approaches by analyzing the Fantasia database from www.physionet.org. Furthermore, the ECG signals of 24 healthy subjects placed in an 3 T MR-scanner were acquired.

  13. A Novel ECG Data Compression Method Using Adaptive Fourier Decomposition With Security Guarantee in e-Health Applications.

    Science.gov (United States)

    Ma, JiaLi; Zhang, TanTan; Dong, MingChui

    2015-05-01

    This paper presents a novel electrocardiogram (ECG) compression method for e-health applications by adapting an adaptive Fourier decomposition (AFD) algorithm hybridized with a symbol substitution (SS) technique. The compression consists of two stages: first stage AFD executes efficient lossy compression with high fidelity; second stage SS performs lossless compression enhancement and built-in data encryption, which is pivotal for e-health. Validated with 48 ECG records from MIT-BIH arrhythmia benchmark database, the proposed method achieves averaged compression ratio (CR) of 17.6-44.5 and percentage root mean square difference (PRD) of 0.8-2.0% with a highly linear and robust PRD-CR relationship, pushing forward the compression performance to an unexploited region. As such, this paper provides an attractive candidate of ECG compression method for pervasive e-health applications.

  14. Assessment of atrial fibrillation ablation outcomes with clinic ECG, monthly 24-h Holter ECG, and twice-daily telemonitoring ECG.

    Science.gov (United States)

    Kimura, Takehiro; Aizawa, Yoshiyasu; Kurata, Naomi; Nakajima, Kazuaki; Kashimura, Shin; Kunitomi, Akira; Nishiyama, Takahiko; Katsumata, Yoshinori; Nishiyama, Nobuhiro; Fukumoto, Kotaro; Tanimoto, Yoko; Fukuda, Keiichi; Takatsuki, Seiji

    2017-03-01

    Differences in the methodologies for evaluating atrial fibrillation (AF) ablation outcomes should be evaluated. In the present study, we compared the AF ablation outcomes among periodic clinic electrocardiography (ECG), 24-h Holter ECG, and telemonitoring ECG to evaluate the differences among these methods. In addition, we evaluated the AF-free survival rate for each method with different durations of the blanking period. A total of 30 AF patients were followed up for 6 months after initial catheter ablation, with clinic ECG on every clinic visit, monthly 24-h Holter ECG, and telemonitoring ECG twice daily and upon symptoms. AF relapse was defined as AF or atrial tachycardia detected with any of the methods. Two patients dropped out of the study, and 28 patients were followed up for 8.8 ± 2.7 months. Patients underwent 3.6 ± 0.8 clinic ECG, 5.1 ± 0.8 Holter ECG, and 273 ± 68 telemonitoring ECG examinations. During the first, second, third, fourth, fifth, and sixth months of follow-up, Holter ECG detected relapses in 11.1, 8.3, 11.5, 15.4, 4.2, and 4.8 % of patients and telemonitoring ECG detected relapses in 32.1, 25.0, 25.0, 17.9, 28.6, and 17.9 % of patients, respectively. When no duration was set for the blanking period, the AF-free survival rate was significantly lower with telemonitoring ECG (46.4 %) than with Holter ECG (78.6 %, P = 0.013) or clinic ECG (85.7 %, P = 0.002). In addition, when the duration of the blanking period was set to 3 months, the AF-free survival rate was significantly lower with telemonitoring ECG than with clinic ECG (92.9 vs. 71.4 %, P = 0.041). The AF ablation outcomes with twice-daily telemonitoring ECG might differ from those with clinic ECG when the duration of the blanking period is 0-3 months. A follow-up based solely on clinic ECG might underestimate AF recurrence.

  15. Improving ECG classification accuracy using an ensemble of neural network modules.

    Directory of Open Access Journals (Sweden)

    Mehrdad Javadi

    Full Text Available This paper illustrates the use of a combined neural network model based on Stacked Generalization method for classification of electrocardiogram (ECG beats. In conventional Stacked Generalization method, the combiner learns to map the base classifiers' outputs to the target data. We claim adding the input pattern to the base classifiers' outputs helps the combiner to obtain knowledge about the input space and as the result, performs better on the same task. Experimental results support our claim that the additional knowledge according to the input space, improves the performance of the proposed method which is called Modified Stacked Generalization. In particular, for classification of 14966 ECG beats that were not previously seen during training phase, the Modified Stacked Generalization method reduced the error rate for 12.41% in comparison with the best of ten popular classifier fusion methods including Max, Min, Average, Product, Majority Voting, Borda Count, Decision Templates, Weighted Averaging based on Particle Swarm Optimization and Stacked Generalization.

  16. Discriminant function analysis of the occurrence risk of abnormal electrocardiogram in thyroidectomized differentiated thyroid carcinoma patients with short-term overt hypothyroidism.

    Science.gov (United States)

    Guan, Feng; Zhao, Hongguang; Jiao, Benzheng; Liu, Shanshan; Sa, Ri; Hou, Sen; Lin, Qiuyu; Wang, Qi; Lin, Chenghe

    2016-02-01

    The common form and risk factors of electrocardiogram (ECG) abnormality in thyroidectomized differentiated thyroid carcinoma (DTC) patients with short-term overt hypothyroidism were investigated and some discriminant formulas for forecasting the occurrence of abnormal ECG in this specific population were deduced in this study. A total of 260 thyroidectomized DTC patients were retrospectively reviewed, 67 of whom had abnormal ECG and 193 normal ECG after short-term (3 weeks) levothyroxine (L-T4) withdrawal. One-way ANOVA, Spearman's rank correlation analysis and discriminant function analysis were performed using data from these DTC patients. A flat or inverted T wave in inferior myocardial and left ventricular wall leads was the most common abnormal ECG finding in short-term overt hypothyroidism. Statistical analyses showed that age, interval, TSH-end (The serum hormothyrin level at the end of L-T4 withdrawal for 3 weeks), and TSH-vel (The average ascending velocity of serum hormothyrin level during L-T4 withdrawal for 3 weeks) were statistically significant and positively correlated with the occurrence of abnormal ECG. Meanwhile, TSH-vel showed the highest correlation coefficient (r = 0.358, p = 0.000). The formulas, especially deduced from age, interval and TSH-vel, could discriminate patients with abnormal ECG or not as high as 77.6 and 70.5%, respectively (resubstitution accuracy: 72.3%). The thyroidectomized DTC patients undergoing short-term L-T4 withdrawal before their first radioiodine ablative therapy, who had one or more of the above-mentioned risk factors, are likely to show abnormal ECG findings. The formulas from discriminant function analysis may be helpful for predicting patients with abnormal ECG with short-term L-T4 withdrawal and allow appropriate medical intervention beforehand.

  17. Code excited linear prediction codec for electrocardiogram.

    Science.gov (United States)

    Banik, Shubhadeep; Martis, Roshan; Nayak, Dayananda

    2004-01-01

    In this paper we propose a CELP ECG codec for medical telemetry. The encoding algorithm is based on CODE-EXCITED LINEAR PREDICTION (CELP). The general framework proposed is: QRS detection, calculation of LPC parameter, generation of residual error signal, codebook generation, MSE (mean square error) search. The codebook is generated for residual error. The indices of the codebook and corresponding LPC parameters are transmitted where the minimum MSE occurs. A replica of the transmitter codebook is present at the receiver. Corresponding to the received index value residual error coefficients are retrieved from the receiver codebook. The ECG signal is reconstructed from the retrieved code word.

  18. Investigating the Effects of the 0.05 Hz First-order High-pass Filter on the Electrocardiogram

    DEFF Research Database (Denmark)

    Isaksen, Jonas; Leber, Remo; Schmid, Ramun

    2016-01-01

    Background: A thorough review is needed for the first-order 0.05 Hz high-pass filter, which was introduced almost fifty years ago before modern techniques were available. We quantify the effectiveness of inverse filtering and assess the changes that the filter imposes on the electrocardiogram (ECG...... ECGs were reconstructed with an RMS error of less than 0.5 μV and a maximum error of ±1 μV (set 1). A clear correlation was found between QRS integral and deviations to the ST-segment (set 2, see Table 1). Any T-wave deviations were poorly described by QRS integral. No correlation was found between QRS...

  19. ECG strain pattern in hypertension is associated with myocardial cellular expansion and diffuse interstitial fibrosis: a multi-parametric cardiac magnetic resonance study.

    Science.gov (United States)

    Rodrigues, Jonathan C L; Amadu, Antonio Matteo; Ghosh Dastidar, Amardeep; McIntyre, Bethannie; Szantho, Gergley V; Lyen, Stephen; Godsave, Cattleya; Ratcliffe, Laura E K; Burchell, Amy E; Hart, Emma C; Hamilton, Mark C K; Nightingale, Angus K; Paton, Julian F R; Manghat, Nathan E; Bucciarelli-Ducci, Chiara

    2017-04-01

    In hypertension, the presence of left ventricular (LV) strain pattern on 12-lead electrocardiogram (ECG) carries adverse cardiovascular prognosis. The underlying mechanisms are poorly understood. We investigated whether hypertensive ECG strain is associated with myocardial interstitial fibrosis and impaired myocardial strain, assessed by multi-parametric cardiac magnetic resonance (CMR). A total of 100 hypertensive patients [50 ± 14 years, male: 58%, office systolic blood pressure (SBP): 170 ± 30 mmHg, office diastolic blood pressure (DBP): 97 ± 14 mmHg) underwent ECG and 1.5T CMR and were compared with 25 normotensive controls (46 ± 14 years, 60% male, SBP: 124 ± 8 mmHg, DBP: 76 ± 7 mmHg). Native T1 and extracellular volume fraction (ECV) were calculated with the modified look-locker inversion-recovery sequence. Myocardial strain values were estimated with voxel-tracking software. ECG strain (n = 20) was associated with significantly higher indexed LV mass (LVM) (119 ± 32 vs. 80 ± 17 g/m2, P ECG strain (n = 80). ECG strain subjects had significantly impaired circumferential strain compared with hypertensive subjects without ECG strain and controls (-15.2 ± 4.7 vs. -17.0 ± 3.3 vs. -17.3 ± 2.4%, P ECG strain subjects to hypertensive subjects with elevated LVM but no ECG strain, a significantly higher ECV (30 ± 4 vs. 28 ± 3%, P ECG strain in multivariate logistic regression analysis [odds ratio (95th confidence interval): 1.07 (1.02-1.12), P ECG strain is a marker of advanced LVH associated with increased interstitial fibrosis and associated with significant myocardial circumferential strain impairment. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Cardiology.

  20. Classification of emotional states from electrocardiogram signals: a non-linear approach based on Hurst.

    Science.gov (United States)

    Selvaraj, Jerritta; Murugappan, Murugappan; Wan, Khairunizam; Yaacob, Sazali

    2013-05-16

    Identifying the emotional state is helpful in applications involving patients with autism and other intellectual disabilities; computer-based training, human computer interaction etc. Electrocardiogram (ECG) signals, being an activity of the autonomous nervous system (ANS), reflect the underlying true emotional state of a person. However, the performance of various methods developed so far lacks accuracy, and more robust methods need to be developed to identify the emotional pattern associated with ECG signals. Emotional ECG data was obtained from sixty participants by inducing the six basic emotional states (happiness, sadness, fear, disgust, surprise and neutral) using audio-visual stimuli. The non-linear feature 'Hurst' was computed using Rescaled Range Statistics (RRS) and Finite Variance Scaling (FVS) methods. New Hurst features were proposed by combining the existing RRS and FVS methods with Higher Order Statistics (HOS). The features were then classified using four classifiers - Bayesian Classifier, Regression Tree, K- nearest neighbor and Fuzzy K-nearest neighbor. Seventy percent of the features were used for training and thirty percent for testing the algorithm. Analysis of Variance (ANOVA) conveyed that Hurst and the proposed features were statistically significant (p classification accuracy. The features obtained by combining FVS and HOS performed better with a maximum accuracy of 92.87% and 76.45% for classifying the six emotional states using random and subject independent validation respectively. The results indicate that the combination of non-linear analysis and HOS tend to capture the finer emotional changes that can be seen in healthy ECG data. This work can be further fine tuned to develop a real time system.

  1. Effects of 900 MHz electromagnetic field emitted by cellular phones on electrocardiograms of guinea pigs.

    Science.gov (United States)

    Meral, I; Tekintangac, Y; Demir, H

    2014-02-01

    This study was carried out to determine the effects of electromagnetic field (EMF) emitted by cellular phones (CPs) on electrocardiograms (ECGs) of guinea pigs. A total of 30 healthy guinea pigs weighing 500-800 g were used. After 1 week of adaptation period, animals were randomly divided into two groups: control group (n = 10) and EMF-exposed group (n = 20). Control guinea pigs were housed in a separate room without exposing them to EMFs of CPs. Animals in second group were exposed to 890-915 MHz EMF (217 Hz of pulse rate, 2 W of maximum peak power and 0.95 wt kg(-1) of specific absorption rate) for 12 h day(-1) (11 h 45 min stand-by and 15 min speaking mode) for 30 days. ECGs of guinea pigs in both the groups were recorded by a direct writing electrocardiograph at the beginning and 10th, 20th and 30th days of the experiment. All ECGs were standardized at 1 mV = 10 mm and with a chart speed of 50 mm sec(-1). Leads I, II, III, lead augmented vector right (aVR), lead augmented vector left (aVL) and lead augmented vector foot (aVF) were recorded. The durations and amplitudes of waves on the trace were measured in lead II. The data were expressed as mean with SEM. It was found that 12 h day(-1) EMF exposure for 30 days did not have any significant effects on ECG findings of guinea pigs. However, this issue needed to be further investigated in a variety of perspectives, such as longer duration of exposure to be able to elucidate the effects of mobile phone-induced EMFs on cardiovascular functions.

  2. Electrocardiogram pattern of some exotic breeds of trained dogs: A variation study

    Directory of Open Access Journals (Sweden)

    Joydip Mukherjee

    2015-11-01

    Full Text Available Aim: The present study has been conducted to evaluate the variation in electrocardiogram (ECG parameters among different trained breeds of dogs (viz. Labrador, German Shepherd, and Golden Retriever used for security reasons. Materials and Methods: The ECG was recorded by single channel ECG at a paper speed of 25 mm/s and calibration of 10 mm=1 mV. The recordings were taken from all the standard bipolar limb leads (Lead-I, II, and III and unipolar augmented limb leads (Lead-aVR, aVL, and aVF. Results: Heart rate was found to be highest in Labrador and lowest in German Shepherd. P-wave duration was maximum in Golden Retriever breed and lowest in Labrador. Maximum amplitude of P-wave was found in Labrador followed by German Shepherd and Golden Retriever. There was significantly (p<0.05 higher values of PR interval in German Shepherd compared to other breeds. The variation in QRS duration, ST segment duration, T-wave duration, and T-wave amplitude was found to be non-significant among breeds. Inverted T-waves were most common in Golden Retriever and German Shepherd, whereas positive T-waves were found in Labrador. There was significant (p<0.05 variation in mean electrical axis of QRS complex among different breeds and it ranges from +60° to +80°. Conclusion: The present study provides the reference values for different ECG parameters to monitor the cardiac health status among Labrador, German Shepherd, and Golden Retriever breeds.

  3. Multiple Intercostal Space Electrocardiogram Allows Accurate Localization of Outflow Tract Ventricular Arrhythmia Origin.

    Science.gov (United States)

    Liu, Zheng; Jia, Yu-He; Ren, Lan; Fang, Pi-Hua; Zhou, Gong-Bu; He, Jia; Zhang, Shu

    2016-02-01

    Multiple intercostal recordings were supposed to get a more comprehensive view of the depolarization vector of the outflow tract ventricular arrhythmia (OT-VA), which may help to identify the OT-VA more accurately. This study was undertaken to develop a more accurate electrocardiogram (ECG) criterion for differentiating between left and right OT-VA origins. We studied OT-VA with a left bundle branch block pattern and inferior axis QRS morphology in 47 patients with successful catheter ablation in the right ventricular OT (RVOT; n = 37) or aortic coronary cusp (ACC; n = 10). Superior and inferior precordial leads were taken together with the routine 12-lead ECG. The ECG during the OT-VA and during sinus beats were analyzed. Transition ratio, transition zone (TZ) index, R/S amplitude ratio, and R-wave duration ratio were measured in the regular, superior, and inferior precordial leads. The combined TZ index, TZ index inferior was significantly smaller, while the V2 inferior transition ratio was significantly larger for ACC origins than RVOT origins (P < 0.05). The area under the curve for the combined TZ index by a receiver operating characteristic analysis was 0.974, which was significantly larger than other parameters. A cutoff value ≤0.25 predicted an ACC origin with 94% sensitivity and 100% specificity. This advantage of the parameter over others also held true for a subanalysis of OT-VAs with a lead V3 precordial transition or TZ index = 0. The combined TZ index outperformed other ECG criteria to differentiate left from right OT-VA origins. ©2015 Wiley Periodicals, Inc.

  4. The surface electrocardiogram predicts risk of heart block during right heart catheterization in patients with preexisting left bundle branch block: implications for the definition of complete left bundle branch block.

    Science.gov (United States)

    Padanilam, Benzy J; Morris, Kent E; Olson, Jeff A; Rippy, Janet S; Walsh, Mary Norine; Subramanian, Natrajan; Vidal, Alex; Prystowsky, Eric N; Steinberg, Leonard A

    2010-07-01

    Patients with left bundle branch block (LBBB) undergoing right heart catheterization can develop complete heart block (CHB) or right bundle branch block (RBBB) in response to right bundle branch (RBB) trauma. We hypothesized that LBBB patients with an initial r wave (>or=1 mm) in lead V1 have intact left to right ventricular septal (VS) activation suggesting persistent conduction over the left bundle branch. Trauma to the RBB should result in RBBB pattern rather than CHB in such patients. Between January 2002 and February 2007, we prospectively evaluated 27 consecutive patients with LBBB developing either CHB or RBBB during right heart catheterization. The prevalence of an r wave >or=1 mm in lead V1 was determined using 118 serial LBBB electrocardiographs (ECGs) from our hospital database. Catheter trauma to the RBB resulted in CHB in 18 patients and RBBB in 9 patients. All 6 patients with >or=1 mm r wave in V1 developed RBBB. Among these 6 patients q wave in lead I, V5, or V6 were present in 3. Four patients (3 in CHB group and 1 in RBBB group) developed spontaneous CHB during a median follow-up of 61 months. V1 q wave >or=1 mm was present in 28% of hospitalized complete LBBB patients. An initial r wave of >or=1 mm in lead V1 suggests intact left to right VS activation and identifies LBBB patients at low risk of CHB during right heart catheterization. These preliminary findings indicate that an initial r wave of >or=1 mm in lead V1, present in approximately 28% of ECGs with classically defined LBBB, may constitute a new exclusion criterion when defining complete LBBB.

  5. Evaluation of an exposed-radiation dose on a dual-source cardiac computed tomography examination with a prospective electrocardiogram-gated fast dual spiral scan

    International Nuclear Information System (INIS)

    Matsubara, Kosuke; Koshida, Kichiro; Koshida, Haruka; Sakuta, Keita; Hayashi, Hiroyuki; Takata, Tadanori; Horii, Junsei; Kawai, Keiichi; Yamamoto, Tomoyuki

    2012-01-01

    We evaluated exposed-radiation doses on dual-source cardiac computed tomography (CT) examinations with prospective electrocardiogram (ECG)-gated fast dual spiral scans. After placing dosimeters at locations corresponding to each of the thoracic organs, prospective ECG-gated fast dual spirals and retrospective ECG-gated dual spiral scans were performed to measure the absorbed dose of each organ. In the prospective ECG-gated fast dual spiral scans, the average absorbed doses were 5.03 mGy for the breast, 9.96 mGy for the heart, 6.60 mGy for the lung, 6.48 mGy for the bone marrow, 9.73 mGy for the thymus, and 4.58 mGy for the skin. These values were about 5% of the absorbed doses for the retrospective ECG-gated dual spiral scan. However, the absorbed dose differed greatly at each scan, especially in the external organs such as the breast. For effective and safe use of the prospective ECG-gated fast dual spiral scan, it is necessary to understand these characteristics sufficiently. (author)

  6. Multiple ECG Fiducial Points-Based Random Binary Sequence Generation for Securing Wireless Body Area Networks.

    Science.gov (United States)

    Zheng, Guanglou; Fang, Gengfa; Shankaran, Rajan; Orgun, Mehmet A; Zhou, Jie; Qiao, Li; Saleem, Kashif

    2017-05-01

    Generating random binary sequences (BSes) is a fundamental requirement in cryptography. A BS is a sequence of N bits, and each bit has a value of 0 or 1. For securing sensors within wireless body area networks (WBANs), electrocardiogram (ECG)-based BS generation methods have been widely investigated in which interpulse intervals (IPIs) from each heartbeat cycle are processed to produce BSes. Using these IPI-based methods to generate a 128-bit BS in real time normally takes around half a minute. In order to improve the time efficiency of such methods, this paper presents an ECG multiple fiducial-points based binary sequence generation (MFBSG) algorithm. The technique of discrete wavelet transforms is employed to detect arrival time of these fiducial points, such as P, Q, R, S, and T peaks. Time intervals between them, including RR, RQ, RS, RP, and RT intervals, are then calculated based on this arrival time, and are used as ECG features to generate random BSes with low latency. According to our analysis on real ECG data, these ECG feature values exhibit the property of randomness and, thus, can be utilized to generate random BSes. Compared with the schemes that solely rely on IPIs to generate BSes, this MFBSG algorithm uses five feature values from one heart beat cycle, and can be up to five times faster than the solely IPI-based methods. So, it achieves a design goal of low latency. According to our analysis, the complexity of the algorithm is comparable to that of fast Fourier transforms. These randomly generated ECG BSes can be used as security keys for encryption or authentication in a WBAN system.

  7. Washable and Reliable Textile Electrodes Embedded into Underwear Fabric for Electrocardiography (ECG Monitoring

    Directory of Open Access Journals (Sweden)

    Amale Ankhili

    2018-02-01

    Full Text Available A medical quality electrocardiogram (ECG signal is necessary for permanent monitoring, and an accurate heart examination can be obtained from instrumented underwear only if it is equipped with high-quality, flexible, textile-based electrodes guaranteeing low contact resistance with the skin. The main objective of this article is to develop reliable and washable ECG monitoring underwear able to record and wirelessly send an ECG signal in real time to a smart phone and further to a cloud. The article focuses on textile electrode design and production guaranteeing optimal contact impedance. Therefore, different types of textile fabrics were coated with modified poly(3,4-ethylenedioxythiophene:poly(styrenesulfonate (PEDOT:PSS in order to develop and manufacture reliable and washable textile electrodes assembled to female underwear (bras, by sewing using commercially available conductive yarns. Washability tests of connected underwear containing textile electrodes and conductive threads were carried out up to 50 washing cycles. The influence of standardized washing cycles on the quality of ECG signals and the electrical properties of the textile electrodes were investigated and characterized.

  8. Isolated T Wave Inversion in Lead aVL: An ECG Survey and a Case Report

    Directory of Open Access Journals (Sweden)

    Getaw Worku Hassen

    2015-01-01

    Full Text Available Background. Computerized electrocardiogram (ECG analysis has been of tremendous help for noncardiologists, but can we rely on it? The importance of ST depression and T wave inversions in lead aVL has not been emphasized and not well recognized across all specialties. Objective. This study’s goal was to analyze if there is a discrepancy of interpretation by physicians from different specialties and a computer-generated ECG reading in regard to a TWI in lead aVL. Methods. In this multidisciplinary prospective study, a single ECG with isolated TWI in lead aVL that was interpreted by the computer as normal was given to all participants to interpret in writing. The readings by all physicians were compared by level of education and by specialty to one another and to the computer interpretation. Results. A total of 191 physicians participated in the study. Of the 191 physicians 48 (25.1% identified and 143 (74.9% did not identify the isolated TWI in lead aVL. Conclusion. Our study demonstrated that 74.9% did not recognize the abnormality. New and subtle ECG findings should be emphasized in their training so as not to miss significant findings that could cause morbidity and mortality.

  9. ECG-Edit function in multidetector-row computed tomography coronary arteriography for patients with arrhythmias

    International Nuclear Information System (INIS)

    Matsutani, Hideyuki; Sano, Tomonari; Kondo, Takeshi

    2008-01-01

    Electrocardiogram (ECG)-gating is necessary for cardiac computed tomography, but is not suitable for arrhythmias, so the aim of this study was to evaluate the usefulness of the ECG-edit function for this purpose. Of 1,221 patients undergoing 64-row multidetector-row computed tomography coronary angiography (coronary MDCT), 123 patients (28 atrial fibrillation (Af), 39 premature atrial contractions (PAC), 42 premature ventricular contractions (PVC), 3 PAC+PVC, 10 sinus arrhythmias (SA), and a second-degree atrioventricular block (2deg AVB)) had arrhythmias necessitating the ECG-edit function. Short R-R interval was deleted and mid-diastolic phases were selected from the long R-R intervals using the ''R+absolute time'' method. In the present study, the reconstructed images were evaluated using a triple-grade scale A-C, representing excellent, acceptable, and unacceptable image quality. Image quality, categorized as A, B and C, respectively, was 50%, 36% and 14% for the 28 patients with Af; 56%, 36% and 8% for the 39 PAC patients, and 65%, 33% and 2% in the 42 PVC patients. None of the scans of the PAC+PVC, SA, and 2deg AVB patients was ranked as C. The ECG-edit function is useful for reconstructing coronary MDCT images in many arrhythmias, and provides clinically acceptable images in most cases. (author)

  10. Accelerated free breathing ECG triggered contrast enhanced pulmonary vein magnetic resonance angiography using compressed sensing.

    Science.gov (United States)

    Roujol, Sébastien; Foppa, Murilo; Basha, Tamer A; Akçakaya, Mehmet; Kissinger, Kraig V; Goddu, Beth; Berg, Sophie; Nezafat, Reza

    2014-11-22

    To investigate the feasibility of accelerated electrocardiogram (ECG)-triggered contrast enhanced pulmonary vein magnetic resonance angiography (CE-PV MRA) with isotropic spatial resolution using compressed sensing (CS). Nineteen patients (59±13 y, 11 M) referred for MR were scanned using the proposed accelerated free breathing ECG-triggered 3D CE-PV MRA sequence (FOV=340×340×110 mm3, spatial resolution=1.5×1.5×1.5 mm3, acquisition window=140 ms at mid diastole and CS acceleration factor=5) and a conventional first-pass breath-hold non ECG-triggered 3D CE-PV MRA sequence. CS data were reconstructed offline using low-dimensional-structure self-learning and thresholding reconstruction (LOST) CS reconstruction. Quantitative analysis of PV sharpness and subjective qualitative analysis of overall image quality were performed using a 4-point scale (1: poor; 4: excellent). Quantitative PV sharpness was increased using the proposed approach (0.73±0.09 vs. 0.51±0.07 for the conventional CE-PV MRA protocol, pMRA allows evaluation of PV anatomy with improved sharpness compared to conventional non-ECG gated first-pass CE-PV MRA. This technique may be a valuable alternative for patients in which the first pass CE-PV MRA fails due to inaccurate first pass timing or inability of the patient to perform a 20-25 seconds breath-hold.

  11. Intersubject variability and intrasubject reproducibility of 12-lead ECG metrics: Implications for human verification.

    Science.gov (United States)

    Jekova, Irena; Krasteva, Vessela; Leber, Remo; Schmid, Ramun; Twerenbold, Raphael; Müller, Christian; Reichlin, Tobias; Abächerli, Roger

    Electrocardiogram (ECG) biometrics is an advanced technology, not yet covered by guidelines on criteria, features and leads for maximal authentication accuracy. This study aims to define the minimal set of morphological metrics in 12-lead ECG by optimization towards high reliability and security, and validation in a person verification model across a large population. A standard 12-lead resting ECG database from 574 non-cardiac patients with two remote recordings (>1year apart) was used. A commercial ECG analysis module (Schiller AG) measured 202 morphological features, including lead-specific amplitudes, durations, ST-metrics, and axes. Coefficient of variation (CV, intersubject variability) and percent-mean-absolute-difference (PMAD, intrasubject reproducibility) defined the optimization (PMAD/CV→min) and restriction (CVfeatures. Linear discriminant analysis (LDA) validated the non-redundant feature set for person verification. Maximal LDA verification sensitivity (85.3%) and specificity (86.4%) were validated for 11 optimal features: R-amplitude (I,II,V1,V2,V3,V5), S-amplitude (V1,V2), Tnegative-amplitude (aVR), and R-duration (aVF,V1). Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Washable and Reliable Textile Electrodes Embedded into Underwear Fabric for Electrocardiography (ECG) Monitoring.

    Science.gov (United States)

    Ankhili, Amale; Tao, Xuyuan; Cochrane, Cédric; Coulon, David; Koncar, Vladan

    2018-02-07

    A medical quality electrocardiogram (ECG) signal is necessary for permanent monitoring, and an accurate heart examination can be obtained from instrumented underwear only if it is equipped with high-quality, flexible, textile-based electrodes guaranteeing low contact resistance with the skin. The main objective of this article is to develop reliable and washable ECG monitoring underwear able to record and wirelessly send an ECG signal in real time to a smart phone and further to a cloud. The article focuses on textile electrode design and production guaranteeing optimal contact impedance. Therefore, different types of textile fabrics were coated with modified poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) in order to develop and manufacture reliable and washable textile electrodes assembled to female underwear (bras), by sewing using commercially available conductive yarns. Washability tests of connected underwear containing textile electrodes and conductive threads were carried out up to 50 washing cycles. The influence of standardized washing cycles on the quality of ECG signals and the electrical properties of the textile electrodes were investigated and characterized.

  13. Switching Kalman filter based methods for apnea bradycardia detection from ECG signals.

    Science.gov (United States)

    Montazeri Ghahjaverestan, Nasim; Shamsollahi, Mohammad B; Ge, Di; Hernández, Alfredo I

    2015-09-01

    Apnea bradycardia (AB) is an outcome of apnea occurrence in preterm infants and is an observable phenomenon in cardiovascular signals. Early detection of apnea in infants under monitoring is a critical challenge for the early intervention of nurses. In this paper, we introduce two switching Kalman filter (SKF) based methods for AB detection using electrocardiogram (ECG) signal.The first SKF model uses McSharry's ECG dynamical model integrated in two Kalman filter (KF) models trained for normal and AB intervals. Whereas the second SKF model is established by using only the RR sequence extracted from ECG and two AR models to be fitted in normal and AB intervals. In both SKF approaches, a discrete state variable called a switch is considered that chooses one of the models (corresponding to normal and AB) during the inference phase. According to the probability of each model indicated by this switch, the model with larger probability determines the observation label at each time instant.It is shown that the method based on ECG dynamical model can be effectively used for AB detection. The detection performance is evaluated by comparing statistical metrics and the amount of time taken to detect AB compared with the annotated onset. The results demonstrate the superiority of this method, with sensitivity and specificity 94.74[Formula: see text] and 94.17[Formula: see text], respectively. The presented approaches may therefore serve as an effective algorithm for monitoring neonates suffering from AB.

  14. Issues in implementing a knowledge-based ECG analyzer for personal mobile health monitoring.

    Science.gov (United States)

    Goh, K W; Kim, E; Lavanya, J; Kim, Y; Soh, C B

    2006-01-01

    Advances in sensor technology, personal mobile devices, and wireless broadband communications are enabling the development of an integrated personal mobile health monitoring system that can provide patients with a useful tool to assess their own health and manage their personal health information anytime and anywhere. Personal mobile devices, such as PDAs and mobile phones, are becoming more powerful integrated information management tools and play a major role in many people's lives. We focus on designing a health-monitoring system for people who suffer from cardiac arrhythmias. We have developed computer simulation models to evaluate the performance of appropriate electrocardiogram (ECG) analysis techniques that can be implemented on personal mobile devices. This paper describes an ECG analyzer to perform ECG beat and episode detection and classification. We have obtained promising preliminary results from our study. Also, we discuss several key considerations when implementing a mobile health monitoring solution. The mobile ECG analyzer would become a front-end patient health data acquisition module, which is connected to the Personal Health Information Management System (PHIMS) for data repository.

  15. ECG data compression using a neural network model based on multi-objective optimization.

    Directory of Open Access Journals (Sweden)

    Bo Zhang

    Full Text Available Electrocardiogram (ECG data analysis is of great significance to the diagnosis of cardiovascular disease. ECG compression should be processed in real time, and the data should be based on lossless compression and have high predictability. In terms of the real time aspect, short-time Fourier transformation is applied to the processing of signal wave for reducing computational time. For the lossless compression requirement, wavelet-transformation that is a coding algorithm can be used to avoid loss of data. In practice, compression is required to avoid storing redundant recording data that are not useful in the diagnosis platform. The obtained data can be preprocessed to remove noise by using wavelet transform, and then a multi-objective optimize neural network model is used to extract feature information. Compared with the existing traditional methods such as direct data processing method and transform method, our proposed compression model has self-learning ability to achieve high data compression ratio at 1:19 without losing important ECG information and compromising quality. Upon testing, we demonstrated that the proposed ECG data compression method based on multi-objective optimization neural network is effective and efficient in clinical practice.

  16. Validity of computational hemodynamics in human arteries based on 3D time-of-flight MR angiography and 2D electrocardiogram gated phase contrast images

    Science.gov (United States)

    Yu, Huidan (Whitney); Chen, Xi; Chen, Rou; Wang, Zhiqiang; Lin, Chen; Kralik, Stephen; Zhao, Ye

    2015-11-01

    In this work, we demonstrate the validity of 4-D patient-specific computational hemodynamics (PSCH) based on 3-D time-of-flight (TOF) MR angiography (MRA) and 2-D electrocardiogram (ECG) gated phase contrast (PC) images. The mesoscale lattice Boltzmann method (LBM) is employed to segment morphological arterial geometry from TOF MRA, to extract velocity profiles from ECG PC images, and to simulate fluid dynamics on a unified GPU accelerated computational platform. Two healthy volunteers are recruited to participate in the study. For each volunteer, a 3-D high resolution TOF MRA image and 10 2-D ECG gated PC images are acquired to provide the morphological geometry and the time-varying flow velocity profiles for necessary inputs of the PSCH. Validation results will be presented through comparisons of LBM vs. 4D Flow Software for flow rates and LBM simulation vs. MRA measurement for blood flow velocity maps. Indiana University Health (IUH) Values Fund.

  17. ECG changes in hyperemesis gravidarum.

    Science.gov (United States)

    Mitchell, Sophie Jessica; Cox, Patricia

    2017-01-04

    This is a case report of a 30-year-old patient presenting at advanced gestation with hyperemesis, who developed a prolonged QT interval secondary to electrolyte imbalance during recovery. This potentially fatal complication should be considered in all patients with hyperemesis gravidarum, especially after a prolonged period of starvation. We hope to highlight the importance of ECG monitoring and careful prescribing in such cases, something that is not considered in current guidelines. 2017 BMJ Publishing Group Ltd.

  18. Initial presenting electrocardiogram as determinant for hospital admission in patients presenting to the emergency department with chest pain: a pilot investigation.

    Science.gov (United States)

    Challa, Prasanna K; Smith, Karen M; Conti, C Richard

    2007-11-01

    Evaluation of chest pain accounts for millions of costly Emergency Department (ED) visits and hospital admissions annually. Of these, approximately 10-20% are myocardial infarctions (MI). Patients with chest pain whose initial electrocardiogram (ECG) is normal do not require hospital admission for evaluation and management of a possible myocardial infarction. The medical records of a consecutive cohort of 250 patients who presented to the ED with chest pain and were admitted by the ED physician to a cardiology inpatient service of an academic tertiary care medical center were reviewed. Reasons for admission to hospital was to rule out an acute coronary syndrome, specifically, myocardial infarction. The initial ECG of each patient was evaluated for abnormalities and compared with the final diagnosis. Of the 75 patients presenting with normal ECGs (normal, upright T waves and isoelectric ST segments), 1 (1.3%) was subsequently diagnosed with a myocardial infarction by Troponin I elevation alone. Of the 55 patients presenting with abnormal ECGs but no clear evidence of ischemia [i.e., left bundle branch block (LBBB), right bundle branch block (RBBB), left anterior hemiblock (LAH)], 2 (3.6%) were diagnosed with MI. Of the 48 patients presenting with abnormal ECGs questionable for ischemia (nonspecific ST and T wave changes that were not clearly ST segment elevation or depression), 7 (14.6%) were diagnosed with an MI. Of the 72 patients who presented with abnormal ECGs showing ischemia (acute ST segment elevation and/or depression), 39 (54.2%) were shown to have evidence for MI. Patients who presented with normal ECGs (category 1) were extremely low risk for acute myocardial infarction. Patients with abnormal ECGs but no evidence of definite ischemia (category 2) had a relatively low incidence of MI. Patients with abnormal ECGs questionable for ischemia (category 3) had an intermediate risk of acute myocardial infarction. The majority of patients with abnormal ECGs

  19. Clinical and Financial Impact of Ordering an Echocardiogram in Children with Left Axis Deviation on Their Electrocardiogram.

    Science.gov (United States)

    Ravi, Prasad; Ashwath, Ravi; Strainic, James; Li, Hong; Steinberg, Jon; Snyder, Christopher

    2016-01-01

    Left axis deviation (LAD) on the electrocardiogram (ECG) is associated with congenital heart disease (CHD), prompting the clinician to order further testing when evaluating a patient with this finding. The purpose is to (1) compare the physical examination (PE) by a pediatric cardiologist to echocardiogram (ECHO) findings in patients with LAD on resting ECG and (2) assess cost of performing ECHO on all patients with LAD on ECG. An IRB approved, retrospective cohort study was performed on patients with LAD (QRS axis ≥0° to -90°) on ECG between 01/02 and 12/12. age >0.25 and <18 years, non-postoperative, and PE and ECHO by pediatric cardiologist. A decision tree model analyzed cost of ECHO in patients with LAD and normal/abnormal PE. Cost of complete ECHO ($239.00) was obtained from 2014 Medicare reimbursement rates. A total of 146 patients met inclusion criteria with 46.5% (68) having normal PE and ECHO, 1.4% (2) having normal PE and abnormal ECHO, 47.3% (69) having abnormal PE and ECHO, and 4.8% (7) having an abnormal PE and normal ECHO. Sensitivity and specificity of PE for detecting abnormalities in this population was 97% and 90%. Positive and negative predictive value of PE was 91% and 97.5%. In patients with normal PE, the cost to identify an ECHO abnormality was $8365, and $263 for those with abnormal PE. In presence of LAD on ECG, the sensitivity, specificity, and positive and negative predictive values of PE by a pediatric cardiologist are excellent at identifying CHD. Performing an ECHO on patients with LAD on ECG is only cost effective in the presence of an abnormal PE. In the presence of normal PE, there is a possibility of missing incidental structural cardiac disease in approximately 2% if an ECHO is not performed. © 2015 Wiley Periodicals, Inc.

  20. The Cardiac Safety Research Consortium electrocardiogram warehouse: thorough QT database specifications and principles of use for algorithm development and testing.

    Science.gov (United States)

    Kligfield, Paul; Green, Cynthia L; Mortara, Justin; Sager, Philip; Stockbridge, Norman; Li, Michael; Zhang, Joanne; George, Samuel; Rodriguez, Ignacio; Bloomfield, Daniel; Krucoff, Mitchell W

    2010-12-01

    This document examines the formation, structure, and principles guiding the use of electrocardiogram (ECG) data sets obtained during thorough QT studies that have been derived from the ECG Warehouse of the Cardiac Safety Research Consortium (CSRC). These principles are designed to preserve the fairness and public interest of access to these data, commensurate with the mission of the CSRC. The data sets comprise anonymized XML formatted digitized ECGs and descriptive variables from placebo and positive control arms of individual studies previously submitted on a proprietary basis to the US Food and Drug Administration by pharmaceutical sponsors. Sponsors permit the release of these studies into the public domain through the CSRC on behalf of the Food and Drug Administration's Critical Path Initiative and public health interest. For algorithm research protocols submitted to and approved by CSRC, unblinded "training" ECG data sets are provided for algorithm development and for initial evaluation, whereas separate blinded "testing" data sets are used for formal algorithm evaluation in cooperation with the CSRC according to methods detailed in this document. Copyright © 2010 Mosby, Inc. All rights reserved.

  1. Independent component analysis-based artefact reduction: application to the electrocardiogram for improved magnetic resonance imaging triggering

    International Nuclear Information System (INIS)

    Oster, Julien; Pietquin, Olivier; Felblinger, Jacques; Abächerli, Roger; Kraemer, Michel

    2009-01-01

    Electrocardiogram (ECG) is required during magnetic resonance (MR) examination for monitoring patients under anaesthesia or with heart diseases and for synchronizing image acquisition with heart activity (triggering). Accurate and fast QRS detection is therefore desirable, but this task is complicated by artefacts related to the complex MR environment (high magnetic field, radio-frequency pulses and fast switching magnetic gradients). Specific signal processing has been proposed, whether using specific MR QRS detectors or ECG denoising methods. Most state-of-the-art techniques use a connection to the MR system for achieving their task, which is a major drawback since access to the MR system is often restricted. This paper introduces a new method for on-line ECG signal enhancement, called ICARE, which takes advantage of using multi-lead ECG and does not require any connection to the MR system. It is based on independent component analysis (ICA) and applied in real time. This algorithm yields accurate QRS detection for efficient triggering

  2. Electrocardiogram and echocardiographic study of left ventricular hypertrophy in patients with essential hypertension in a teaching medical college

    Directory of Open Access Journals (Sweden)

    K Venugopal

    2016-01-01

    Full Text Available Background: Left ventricular hypertrophy (LVH is the adaptive mechanism for increased left ventricular (LV stress and is associated with many adverse events. This study was undertaken to study LVH in patients of essential hypertension and to correlate between clinical, electrocardiogram (ECG, and echocardiography (ECHO in the identification of LVH. Materials and Methods: One hundred patients attending the outpatient department and those who were admitted in our teaching institute from January 2013 to June 2014 were the study subjects. All cases of essential hypertension, irrespective of the duration of hypertension and type of treatment received were included in the study. Patients with secondary hypertension, ischemic heart disease/myocardial infarction, ischemic cardiomyopathy, congenital heart disease, and valvular heart disease were excluded. Conclusion: Out of the different ECG criteria, total QRS criteria showed a high sensitivity of 60%. ECG criteria have a high specificity but low sensitivity and hence, have limited use as a screening method. However, in a resource-poor country such as India where ECHO facilities are not available in all rural regions, improved ECG criteria such as total QRS voltage can be recommended as a routine investigation for LVH because of its cost-effectiveness and easy availability despite certain limitations.

  3. Assessment of the exercise electrocardiogram in women versus men using tomographic myocardial perfusion imaging as the reference standard.

    Science.gov (United States)

    Miller, T D; Roger, V L; Milavetz, J J; Hopfenspirger, M R; Milavetz, D L; Hodge, D O; Gibbons, R J

    2001-04-01

    The exercise electrocardiogram (ECG) is widely believed to be less accurate in women, primarily due to a high prevalence of false-positive tests. The purpose of this study was to examine the relative accuracy of the exercise ECG in women versus men in 8,671 patients (3,213 women, 5,458 men) using myocardial perfusion imaging as the reference standard. More women (14%) than men (10%) had a false-positive ECG (p women (17% vs 32%, p men, women had lower test sensitivity (30% vs 42%, p higher specificity (82% vs 78%, p = 0.002), negative predictive value (78% vs 52%, p accuracy (69% vs 58%, p women (12% vs 19%, p women, 838 men), the false-positive electrocardiographic rate was again higher in women (13% vs 7%, p = 0.003), but neither specificity (69% vs 74%, p = NS) nor accuracy (60% vs 66%, p = NS) was different between the sexes. Thus, the percentage of patients with a false-positive exercise ECG was higher in women than men but low in absolute terms (women. These results suggest that gender should not be a major determinant for selecting stress imaging over standard treadmill testing.

  4. [Integral parameters of electrocardiogram: perfection of assessment].

    Science.gov (United States)

    Volobuev, A N; Kondurtsev, V A; Romanchuk, P I; Bazarova, V N

    2001-01-01

    The role of such parameter as electric quality of the heart (EQH) is assessed by a biophysical analysis of a new model of dipolic equivalent electric generator of the heart taking account of myocardial inductivity in the course of excitation. How to estimate EQH by standard ECG parameters using calculated nomogram is shown. Results of EQH estimation in the course of treatment are provided.

  5. Prehospital ECG transmission: comparison of advanced mobile phone and facsimile devices in an urban Emergency Medical Service System.

    Science.gov (United States)

    Väisänen, Olli; Mäkijärvi, Markku; Silfvast, Tom

    2003-05-01

    To compare the speed and reliability of electrocardiogram (ECG) transmissions from the prehospital setting to a conventional table facsimile device and to an advanced mobile phone in a Helicopter Emergency Medical Service System (HEMS). Eighteen authentic ECGs stored in the memory module of a monitor defibrillator were used. The ECGs were (1) sent directly from the monitor defibrillator to a table fax and an advanced mobile phone at the HEMS base; (2) printed out and sent from a mobile fax connected to an ordinary mobile phone to the table fax and the advanced mobile phone at the HEMS base; (3) printed out and sent from an ordinary table fax as well as from a table fax connected to a satellite phone system to the receiving devices at the HEMS base. When the ECGs were sent from the table fax via satellite, the transmission times were longer to the advanced mobile phone than to the table fax at the HEMS base (1 min 54 s+/-0 min 21 s vs. 1 min 37 s+/-0 min 20 s, (mean+/-SD), (Ptransmission from the other fax devices, there were no differences in transmission times between the two receiving devices. The fastest way to transmit ECGs to the advanced mobile phone was to send it from conventional table fax (1 min 22 s+/-0 min 18 s) and the longest transmission times were with mobile fax connected to mobile phone (5 min 23 s+/-3 min 5 s). In all ECGs transmitted except one the cardiac rhythm and ST-changes could be recognised. An advanced mobile phone is as fast and reliable as a conventional table fax in receiving ECGs. A mobile phone with advanced features is a practical tool for HEMS physicians who need to evaluate ECGs in the prehospital setting.

  6. Performance of handheld electrocardiogram devices to detect atrial fibrillation in a cardiology and geriatric ward setting.

    Science.gov (United States)

    Desteghe, Lien; Raymaekers, Zina; Lutin, Mark; Vijgen, Johan; Dilling-Boer, Dagmara; Koopman, Pieter; Schurmans, Joris; Vanduynhoven, Philippe; Dendale, Paul; Heidbuchel, Hein

    2017-01-01

    To determine the usability, accuracy, and cost-effectiveness of two handheld single-lead electrocardiogram (ECG) devices for atrial fibrillation (AF) screening in a hospital population with an increased risk for AF. Hospitalized patients (n = 445) at cardiological or geriatric wards were screened for AF by two handheld ECG devices (MyDiagnostick and AliveCor). The performance of the automated algorithm of each device was evaluated against a full 12-lead or 6-lead ECG recording. All ECGs and monitor tracings were also independently reviewed in a blinded fashion by two electrophysiologists. Time investments by nurses and physicians were tracked and used to estimate cost-effectiveness of different screening strategies. Handheld recordings were not possible in 7 and 21.4% of cardiology and geriatric patients, respectively, because they were not able to hold the devices properly. Even after the exclusion of patients with an implanted device, sensitivity and specificity of the automated algorithms were suboptimal (Cardiology: 81.8 and 94.2%, respectively, for MyDiagnostick; 54.5 and 97.5%, respectively, for AliveCor; Geriatrics: 89.5 and 95.7%, respectively, for MyDiagnostick; 78.9 and 97.9%, respectively, for AliveCor). A scenario based on automated AliveCor evaluation in patients without AF history and without an implanted device proved to be the most cost-effective method, with a provider cost to identify one new AF patient of €193 and €82 at cardiology and geriatrics, respectively. The cost to detect one preventable stroke per year would be €7535 and €1916, respectively (based on average CHA 2 DS 2 -VASc of 3.9 ± 2.0 and 5.0 ± 1.5, respectively). Manual interpretation increases sensitivity, but decreases specificity, doubling the cost per detected patient, but remains cheaper than sole 12-lead ECG screening. Using AliveCor or MyDiagnostick handheld recorders requires a structured screening strategy to be effective and cost-effective in a hospital setting

  7. Trend Extraction in Functional Data of Amplitudes of R and T Waves in Exercise Electrocardiogram

    Science.gov (United States)

    Cammarota, Camillo; Curione, Mario

    The amplitudes of R and T waves of the electrocardiogram (ECG) recorded during the exercise test show both large inter- and intra-individual variability in response to stress. We analyze a dataset of 65 normal subjects undergoing ambulatory test. We model the dataset of R and T series in the framework of functional data, assuming that the individual series are realizations of a non-stationary process, centered at the population trend. We test the time variability of this trend computing a simultaneous confidence band and the zero crossing of its derivative. The analysis shows that the amplitudes of the R and T waves have opposite responses to stress, consisting respectively in a bump and a dip at the early recovery stage. Our findings support the existence of a relationship between R and T wave amplitudes and respectively diastolic and systolic ventricular volumes.

  8. Hardware-efficient robust biometric identification from 0.58 second template and 12 features of limb (Lead I) ECG signal using logistic regression classifier.

    Science.gov (United States)

    Sahadat, Md Nazmus; Jacobs, Eddie L; Morshed, Bashir I

    2014-01-01

    The electrocardiogram (ECG), widely known as a cardiac diagnostic signal, has recently been proposed for biometric identification of individuals; however reliability and reproducibility are of research interest. In this paper, we propose a template matching technique with 12 features using logistic regression classifier that achieved high reliability and identification accuracy. Non-invasive ECG signals were captured using our custom-built ambulatory EEG/ECG embedded device (NeuroMonitor). ECG data were collected from healthy subjects (10), between 25-35 years, for 10 seconds per trial. The number of trials from each subject was 10. From each trial, only 0.58 seconds of Lead I ECG data were used as template. Hardware-efficient fiducial point detection technique was implemented for feature extraction. To obtain repeated random sub-sampling validation, data were randomly separated into training and testing sets at a ratio of 80:20. Test data were used to find the classification accuracy. ECG template data with 12 extracted features provided the best performance in terms of accuracy (up to 100%) and processing complexity (computation time of 1.2ms). This work shows that a single limb (Lead I) ECG can robustly identify an individual quickly and reliably with minimal contact and data processing using the proposed algorithm.

  9. Automated diagnosis of congestive heart failure using dual tree complex wavelet transform and statistical features extracted from 2s of ECG signals.

    Science.gov (United States)

    Sudarshan, Vidya K; Acharya, U Rajendra; Oh, Shu Lih; Adam, Muhammad; Tan, Jen Hong; Chua, Chua Kuang; Chua, Kok Poo; Tan, Ru San

    2017-04-01

    Identification of alarming features in the electrocardiogram (ECG) signal is extremely significant for the prediction of congestive heart failure (CHF). ECG signal analysis carried out using computer-aided techniques can speed up the diagnosis process and aid in the proper management of CHF patients. Therefore, in this work, dual tree complex wavelets transform (DTCWT)-based methodology is proposed for an automated identification of ECG signals exhibiting CHF from normal. In the experiment, we have performed a DTCWT on ECG segments of 2s duration up to six levels to obtain the coefficients. From these DTCWT coefficients, statistical features are extracted and ranked using Bhattacharyya, entropy, minimum redundancy maximum relevance (mRMR), receiver-operating characteristics (ROC), Wilcoxon, t-test and reliefF methods. Ranked features are subjected to k-nearest neighbor (KNN) and decision tree (DT) classifiers for automated differentiation of CHF and normal ECG signals. We have achieved 99.86% accuracy, 99.78% sensitivity and 99.94% specificity in the identification of CHF affected ECG signals using 45 features. The proposed method is able to detect CHF patients accurately using only 2s of ECG signal length and hence providing sufficient time for the clinicians to further investigate on the severity of CHF and treatments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Mouse ECG findings in aging, with conduction system affecting drugs and in cardiac pathologies: Development and validation of ECG analysis algorithm in mice.

    Science.gov (United States)

    Merentie, Mari; Lipponen, Jukka A; Hedman, Marja; Hedman, Antti; Hartikainen, Juha; Huusko, Jenni; Lottonen-Raikaslehto, Line; Parviainen, Viktor; Laidinen, Svetlana; Karjalainen, Pasi A; Ylä-Herttuala, Seppo

    2015-12-01

    Mouse models are extremely important in studying cardiac pathologies and related electrophysiology, but very few mouse ECG analysis programs are readily available. Therefore, a mouse ECG analysis algorithm was developed and validated. Surface ECG (lead II) was acquired during transthoracic echocardiography from C57Bl/6J mice under isoflurane anesthesia. The effect of aging was studied in young (2-3 months), middle-aged (14 months) and old (20-24 months) mice. The ECG changes associated with pharmacological interventions and common cardiac pathologies, that is, acute myocardial infarction (AMI) and progressive left ventricular hypertrophy (LVH), were studied. The ECG raw data were analyzed with an in-house ECG analysis program, modified specially for mouse ECG. Aging led to increases in P-wave duration, atrioventricular conduction time (PQ interval), and intraventricular conduction time (QRS complex width), while the R-wave amplitude decreased. In addition, the prevalence of arrhythmias increased during aging. Anticholinergic atropine shortened PQ time, and beta blocker metoprolol and calcium-channel blocker verapamil increased PQ interval and decreased heart rate. The ECG changes after AMI included early JT elevation, development of Q waves, decreased R-wave amplitude, and later changes in JT/T segment. In progressive LVH model, QRS complex width was increased at 2 and especially 4 weeks timepoint, and also repolarization abnormalities were seen. Aging, drugs, AMI, and LVH led to similar ECG changes in mice as seen in humans, which could be reliably detected with this new algorithm. The developed method will be very useful for studies on cardiovascular diseases in mice. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  11. A Study on the Optimal Positions of ECG Electrodes in a Garment for the Design of ECG-Monitoring Clothing for Male.

    Science.gov (United States)

    Cho, Hakyung; Lee, Joo Hyeon

    2015-09-01

    Smart clothing is a sort of wearable device used for ubiquitous health monitoring. It provides comfort and efficiency in vital sign measurements and has been studied and developed in various types of monitoring platforms such as T-shirt and sports bra. However, despite these previous approaches, smart clothing for electrocardiography (ECG) monitoring has encountered a serious shortcoming relevant to motion artifacts caused by wearer movement. In effect, motion artifacts are one of the major problems in practical implementation of most wearable health-monitoring devices. In the ECG measurements collected by a garment, motion artifacts are usually caused by improper location of the electrode, leading to lack of contact between the electrode and skin with body motion. The aim of this study was to suggest a design for ECG-monitoring clothing contributing to reduction of motion artifacts. Based on the clothing science theory, it was assumed in this study that the stability of the electrode in a dynamic state differed depending on the electrode location in an ECG-monitoring garment. Founded on this assumption, effects of 56 electrode positions were determined by sectioning the surface of the garment into grids with 6 cm intervals in the front and back of the bodice. In order to determine the optimal locations of the ECG electrodes from the 56 positions, ECG measurements were collected from 10 participants at every electrode position in the garment while the wearer was in motion. The electrode locations indicating both an ECG measurement rate higher than 80.0 % and a large amplitude during motion were selected as the optimal electrode locations. The results of this analysis show four electrode locations with consistently higher ECG measurement rates and larger amplitudes amongst the 56 locations. These four locations were abstracted to be least affected by wearer movement in this research. Based on this result, a design of the garment-formed ECG monitoring platform

  12. An artificial neural network to safely reduce the number of ambulance ECGs transmitted for physician assessment in a system with prehospital detection of ST elevation myocardial infarction

    Directory of Open Access Journals (Sweden)

    Forberg Jakob L

    2012-02-01

    Full Text Available Abstract Background Pre-hospital electrocardiogram (ECG transmission to an expert for interpretation and triage reduces time to acute percutaneous coronary intervention (PCI in patients with ST elevation Myocardial Infarction (STEMI. In order to detect all STEMI patients, the ECG should be transmitted in all cases of suspected acute cardiac ischemia. The aim of this study was to examine the ability of an artificial neural network (ANN to safely reduce the number of ECGs transmitted by identifying patients without STEMI and patients not needing acute PCI. Methods Five hundred and sixty ambulance ECGs transmitted to the coronary care unit (CCU in routine care were prospectively collected. The ECG interpretation by the ANN was compared with the diagnosis (STEMI or not and the need for an acute PCI (or not as determined from the Swedish coronary angiography and angioplasty register. The CCU physician's real time ECG interpretation (STEMI or not and triage decision (acute PCI or not were registered for comparison. Results The ANN sensitivity, specificity, positive and negative predictive values for STEMI was 95%, 68%, 18% and 99%, respectively, and for a need of acute PCI it was 97%, 68%, 17% and 100%. The area under the ANN's receiver operating characteristics curve for STEMI detection was 0.93 (95% CI 0.89-0.96 and for predicting the need of acute PCI 0.94 (95% CI 0.90-0.97. If ECGs where the ANN did not identify a STEMI or a need of acute PCI were theoretically to be withheld from transmission, the number of ECGs sent to the CCU could have been reduced by 64% without missing any case with STEMI or a need of immediate PCI. Conclusions Our ANN had an excellent ability to predict STEMI and the need of acute PCI in ambulance ECGs, and has a potential to safely reduce the number of ECG transmitted to the CCU by almost two thirds.

  13. Implementation of a wireless ECG acquisition SoC for IEEE 802.15.4 (ZigBee) applications.

    Science.gov (United States)

    Wang, Liang-Hung; Chen, Tsung-Yen; Lin, Kuang-Hao; Fang, Qiang; Lee, Shuenn-Yuh

    2015-01-01

    This paper presents a wireless biosignal acquisition system-on-a-chip (WBSA-SoC) specialized for electrocardiogram (ECG) monitoring. The proposed system consists of three subsystems, namely, 1) the ECG acquisition node, 2) the protocol for standard IEEE 802.15.4 ZigBee system, and 3) the RF transmitter circuits. The ZigBee protocol is adopted for wireless communication to achieve high integration, applicability, and portability. A fully integrated CMOS RF front end containing a quadrature voltage-controlled oscillator and a 2.4-GHz low-IF (i.e., zero-IF) transmitter is employed to transmit ECG signals through wireless communication. The low-power WBSA-SoC is implemented by the TSMC 0.18-μm standard CMOS process. An ARM-based displayer with FPGA demodulation and an RF receiver with analog-to-digital mixed-mode circuits are constructed as verification platform to demonstrate the wireless ECG acquisition system. Measurement results on the human body show that the proposed SoC can effectively acquire ECG signals.

  14. A New Method to Detect Driver Fatigue Based on EMG and ECG Collected by Portable Non-Contact Sensors

    Directory of Open Access Journals (Sweden)

    Lin Wang

    2017-11-01

    Full Text Available Recently, detection and prediction on driver fatigue have become interest of research worldwide. In the present work, a new method is built to effectively evaluate driver fatigue based on electromyography (EMG and electrocardiogram (ECG collected by portable real-time and non-contact sensors. First, under the non-disturbance condition for driver’s attention, mixed physiological signals (EMG, ECG and artefacts are collected by non-contact sensors located in a cushion on the driver’s seat. EMG and ECG are effectively separated by FastICA, and de-noised by empirical mode decomposition (EMD. Then, three physiological features, complexity of EMG, complexity of ECG, and sample entropy (SampEn of ECG, are extracted and analysed. Principal components are obtained by principal components analysis (PCA and are used as independent variables. Finally, a mathematical model of driver fatigue is built, and the accuracy of the model is up to 91%. Moreover, based on the questionnaire, the calculation results of model are consistent with real fatigue felt by the participants. Therefore, this model can effectively detect driver fatigue.

  15. NInFEA: an embedded framework for the real-time evaluation of fetal ECG extraction algorithms.

    Science.gov (United States)

    Pani, Danilo; Barabino, Gianluca; Raffo, Luigi

    2013-02-01

    Fetal electrocardiogram (ECG) extraction from non-invasive biopotential recordings is a long-standing research topic. Despite the significant number of algorithms presented in the scientific literature, it is difficult to find information about embedded hardware implementations able to provide real-time support for the required features, bridging the gap between theory and practice. This article presents the NInFEA (non-invasive fetal ECG analysis) tool, an embedded hardware/software framework based on the hybrid dual-core OMAP-L137 low-power processor for the real-time evaluation of fetal ECG extraction algorithms. The hybrid platform, including a digital signal processor (DSP) and a general-purpose processor (GPP), allows achieving the best performance compared with single-core architectures. The GPP provides a portable graphical user interface, whereas the DSP is extensively used for advanced signal processing tasks. As a case study, three state-of-the-art fetal ECG extraction algorithms have been ported onto NInFEA, along with some support routines needed to provide the additional information required by the clinicians and supported by the user interface. NInFEA can be regarded both as a reference design for similar applications and as a common embedded low-power testbed for real-time fetal ECG extraction algorithms.

  16. A Combined Independent Source Separation and Quality Index Optimization Method for Fetal ECG Extraction from Abdominal Maternal Leads.

    Science.gov (United States)

    Billeci, Lucia; Varanini, Maurizio

    2017-05-16

    The non-invasive fetal electrocardiogram (fECG) technique has recently received considerable interest in monitoring fetal health. The aim of our paper is to propose a novel fECG algorithm based on the combination of the criteria of independent source separation and of a quality index optimization (ICAQIO-based). The algorithm was compared with two methods applying the two different criteria independently-the ICA-based and the QIO-based methods-which were previously developed by our group. All three methods were tested on the recently implemented Fetal ECG Synthetic Database (FECGSYNDB). Moreover, the performance of the algorithm was tested on real data from the PhysioNet fetal ECG Challenge 2013 Database. The proposed combined method outperformed the other two algorithms on the FECGSYNDB (ICAQIO-based: 98.78%, QIO-based: 97.77%, ICA-based: 97.61%). Significant differences were obtained in particular in the conditions when uterine contractions and maternal and fetal ectopic beats occurred. On the real data, all three methods obtained very high performances, with the QIO-based method proving slightly better than the other two (ICAQIO-based: 99.38%, QIO-based: 99.76%, ICA-based: 99.37%). The findings from this study suggest that the proposed method could potentially be applied as a novel algorithm for accurate extraction of fECG, especially in critical recording conditions.

  17. An improved algorithm for respiration signal extraction from electrocardiogram measured by conductive textile electrodes using instantaneous frequency estimation.

    Science.gov (United States)

    Park, Sung-Bin; Noh, Yeon-Sik; Park, Sung-Jun; Yoon, Hyoung-Ro

    2008-02-01

    In this paper, an improved algorithm for the extraction of respiration signal from the electrocardiogram (ECG) in home healthcare is proposed. The whole system consists of two-lead electrocardiogram acquisition using conductive textile electrodes located in bed, baseline fluctuation elimination, R-wave detection, adjustment of sudden change in R-wave area using moving average, and optimal lead selection. In order to solve the problems of previous algorithms for the ECG-derived respiration (EDR) signal acquisition, we are proposing a method for the optimal lead selection. An optimal EDR signal among the three EDR signals derived from each lead (and arctangent of their ratio) is selected by estimating the instantaneous frequency using the Hilbert transform, and then choosing the signal with minimum variation of the instantaneous frequency. The proposed algorithm was tested on 15 male subjects, and we obtained satisfactory respiration signals that showed high correlation (r(2) > 0.8) with the signal acquired from the chest-belt respiration sensor.

  18. Fast Electrocardiogram Amplifier Recovery after Defibrillation Shock

    Directory of Open Access Journals (Sweden)

    Ivan Dotsinsky

    2005-04-01

    Full Text Available A procedure for fast ECG amplifier recovery after defibrillation shocks was developed and simulated in the MATLAB environment. Exponentially decaying post-shock voltages have been recorded. Signals from the AHA database are taken and mixed with the recorded exponential disturbances. The algorithm applies moving averaging (comb filter on the compound input signal, thereby obtaining the samples of the disturbance. They are currently subtracted from the input signal. The results obtained show that its recovery is practically instantaneous.

  19. ECG Denoising Using Marginalized Particle Extended Kalman Filter With an Automatic Particle Weighting Strategy.

    Science.gov (United States)

    Hesar, Hamed Danandeh; Mohebbi, Maryam

    2017-05-01

    In this paper, a model-based Bayesian filtering framework called the "marginalized particle-extended Kalman filter (MP-EKF) algorithm" is proposed for electrocardiogram (ECG) denoising. This algorithm does not have the extended Kalman filter (EKF) shortcoming in handling non-Gaussian nonstationary situations because of its nonlinear framework. In addition, it has less computational complexity compared with particle filter. This filter improves ECG denoising performance by implementing marginalized particle filter framework while reducing its computational complexity using EKF framework. An automatic particle weighting strategy is also proposed here that controls the reliance of our framework to the acquired measurements. We evaluated the proposed filter on several normal ECGs selected from MIT-BIH normal sinus rhythm database. To do so, artificial white Gaussian and colored noises as well as nonstationary real muscle artifact (MA) noise over a range of low SNRs from 10 to -5 dB were added to these normal ECG segments. The benchmark methods were the EKF and extended Kalman smoother (EKS) algorithms which are the first model-based Bayesian algorithms introduced in the field of ECG denoising. From SNR viewpoint, the experiments showed that in the presence of Gaussian white noise, the proposed framework outperforms the EKF and EKS algorithms in lower input SNRs where the measurements and state model are not reliable. Owing to its nonlinear framework and particle weighting strategy, the proposed algorithm attained better results at all input SNRs in non-Gaussian nonstationary situations (such as presence of pink noise, brown noise, and real MA). In addition, the impact of the proposed filtering method on the distortion of diagnostic features of the ECG was investigated and compared with EKF/EKS methods using an ECG diagnostic distortion measure called the "Multi-Scale Entropy Based Weighted Distortion Measure" or MSEWPRD. The results revealed that our proposed

  20. [ECG of the athlete's heart].

    Science.gov (United States)

    Pokan, R; Huonker, M; Schumacher, M; Zweiker, R; Eber, B; Starz, I; Klein, W

    1994-01-01

    The athlete's heart is characterized by eccentric hypertrophy of all cardiac cavities and there is a close connection to increased tone of the vagal system. As a consequence, not only arrhythmias are observed in the ECG of healthy athletes, but also changes in the QRS complex and in the ST-T-segment. Left ventricular hypertrophy is diagnosed in ECG by a positive Sokolow-Lyon index. The frequent finding of a right ventricular conduction delay is possibly due to hypertrophy of the myocardium in the apex of the right ventricle. The causes of various T wave changes are generally unclear and await further diagnostic clarification. In cases when normalization of the T-wave deviation is observed under stress, such changes are of functional nature. Echocardiography is indicated in any case to establish the heart's size and function; hypertrophic cardiomyopathy has to be excluded. Frequent cardiac dysrhythmias found in athletes are sinus bradycardia and sinus arrhythmia, less often escape rhythms are seen. A arrhythmia more often found in athletes is the respiration-dependent simple atrioventricular dissociation. Also, escape rhythms are observed in some cases with ventricular origin. Finally, a pronounced vagotonia can lead to a prolonged conduction time; AV-blocks of all degrees of severity are observed in athletes. The functional character of these arrhythmias can be easily demonstrated by their disappearance under stress.

  1. Pre-Hospital 12-Lead Electrocardiogram within 60 Minutes Differentiates Proximal versus Nonproximal Left Anterior Descending Artery Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    James J McCarthy

    2011-05-01

    Full Text Available Introduction: Acute anterior myocardial infarctions caused by proximal left anterior descending (LAD artery occlusions are associated with a higher morbidity and mortality. Early identification of high-risk patients via the 12-lead electrocardiogram (ECG could assist physicians and emergency response teams in providing early and aggressive care for patients with anterior ST-elevation myocardial infarctions (STEMI. Approximately 25% of US hospitals have primary percutaneous coronary intervention (PCI capability for the treatment of acute myocardial infarctions. Given the paucity of hospitals capable of PCI, early identification of more severe myocardial infarction may prompt emergency medical service routing of these patients to PCI-capable hospitals. We sought to determine if the 12 lead ECG is capable of predicting proximal LAD artery occlusions. Methods: In a retrospective, post-hoc analysis of the Pre-Hospital Administration of Thrombolytic Therapy with Urgent Culprit Artery Revascularization pilot trial, we compared the ECG findings of proximal and nonproximal LAD occlusions for patients who had undergone an ECG within 180 minutes of symptom onset. Results: In this study, 72 patients had anterior STEMIs, with ECGs performed within 180 minutes of symptom onset. In patients who had undergone ECGs within 60 minutes (n¼35, the mean sum of ST elevation (STE in leads V1 through V6 plus ST depression (STD in leads II, III, and aVF was 19.2 mm for proximal LAD occlusions and 11.7 mm for nonproximal LAD occlusions (P¼0.007. A sum STE in V1 through V6 plus STD in II, III, and aVF of at least 17.5 mm had a sensitivity of 52.3%, specificity of 92.9%, positive predictive value of 91.7%, and negative predictive value of 56.5% for proximal LAD occlusions. When the ECG was performed more than 60 minutes after symptom onset (n¼37, there was no significant difference in ST-segment deviation between the 2 groups. Conclusion: The sum STE (V1-V6 and STD (II

  2. A wavelet-based ECG delineation algorithm for 32-bit integer online processing.

    Science.gov (United States)

    Di Marco, Luigi Y; Chiari, Lorenzo

    2011-04-03

    Since the first well-known electrocardiogram (ECG) delineator based on Wavelet Transform (WT) presented by Li et al. in 1995, a significant research effort has been devoted to the exploitation of this promising method. Its ability to reliably delineate the major waveform components (mono- or bi-phasic P wave, QRS, and mono- or bi-phasic T wave) would make it a suitable candidate for efficient online processing of ambulatory ECG signals. Unfortunately, previous implementations of this method adopt non-linear operators such as root mean square (RMS) or floating point algebra, which are computationally demanding. This paper presents a 32-bit integer, linear algebra advanced approach to online QRS detection and P-QRS-T waves delineation of a single lead ECG signal, based on WT. The QRS detector performance was validated on the MIT-BIH Arrhythmia Database (sensitivity Se = 99.77%, positive predictive value P+ = 99.86%, on 109010 annotated beats) and on the European ST-T Database (Se = 99.81%, P+ = 99.56%, on 788050 annotated beats). The ECG delineator was validated on the QT Database, showing a mean error between manual and automatic annotation below 1.5 samples for all fiducial points: P-onset, P-peak, P-offset, QRS-onset, QRS-offset, T-peak, T-offset, and a mean standard deviation comparable to other established methods. The proposed algorithm exhibits reliable QRS detection as well as accurate ECG delineation, in spite of a simple structure built on integer linear algebra.

  3. A first approach to Arrhythmogenic Cardiomyopathy detection through ECG and Hidden Markov Models

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez-Serrano, S.; Sanz Sanchez, J.; Martínez Hinarejos, C.D.; Igual Muñoz, B.; Millet Roig, J.; Zorio Grima, Z.; Castells, F.

    2016-07-01

    Arrhythmogenic Cardiomyopathy (ACM) is a heritable cardiac disease causing sudden cardiac death in young people. Its clinical diagnosis includes major and minor criteria based on alterations of the electrocardiogram (ECG). The aim of this study is to evaluate Hidden Markov Models (HMM) in order to assess its possible potential of classification among subjects affected by ACM and those relatives who do not suffer the disease through 12-lead ECG recordings. Database consists of 12-lead ECG recordings from 32 patients diagnosed with ACM, and 37 relatives of those affected, but without gene mutation. Using the HTK toolkit and a hold-out strategy in order to train and evaluate a set of HMM models, we performed a grid search through the number of states and Gaussians across these HMM models. Results show that two different HMM models achieved the best balance between sensibility and specificity. The first one needed 35 states and 2 Gaussians and its performance was 0.7 and 0.8 in sensibility and specificity respectively. The second one achieved a sensibility and specificity values of 0.8 and 0.7 respectively with 50 states and 4 Gaussians. The results of this study show that HMM models can achieve an acceptable level of sensibility and specificity in the classification among ECG registers between those affected by ACM and the control group. All the above suggest that this approach could help to detect the disease in a non-invasive way, especially within the context of family screening, improving sensitivity in detection by ECG. (Author)

  4. ECG based Atrial Fibrillation detection using Sequency Ordered Complex Hadamard Transform and Hybrid Firefly Algorithm

    Directory of Open Access Journals (Sweden)

    Padmavathi Kora

    2017-06-01

    Full Text Available Electrocardiogram (ECG, a non-invasive diagnostic technique, used for detecting cardiac arrhythmia. From last decade industry dealing with biomedical instrumentation and research, demanding an advancement in its ability to distinguish different cardiac arrhythmia. Atrial Fibrillation (AF is an irregular rhythm of the human heart. During AF, the atrial moments are quicker than the normal rate. As blood is not completely ejected out of atria, chances for the formation of blood clots in atrium. These abnormalities in the heart can be identified by the changes in the morphology of the ECG. The first step in the detection of AF is preprocessing of ECG, which removes noise using filters. Feature extraction is the next key process in this research. Recent feature extraction methods, such as Auto Regressive (AR modeling, Magnitude Squared Coherence (MSC and Wavelet Coherence (WTC using standard database (MIT-BIH, yielded a lot of features. Many of these features might be insignificant containing some redundant and non-discriminatory features that introduce computational burden and loss of performance. This paper presents fast Conjugate Symmetric Sequency Ordered Complex Hadamard Transform (CS-SCHT for extracting relevant features from the ECG signal. The sparse matrix factorization method is used for developing fast and efficient CS-SCHT algorithm and its computational performance is examined and compared to that of the HT and NCHT. The applications of the CS-SCHT in the ECG-based AF detection is also discussed. These fast CS-SCHT features are optimized using Hybrid Firefly and Particle Swarm Optimization (FFPSO to increase the performance of the classifier.

  5. The clinical factors′ prediction of increased intradialytic qt dispersion on the electrocardiograms of chronic hemodialysis patients

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    Dina Oktavia

    2013-01-01

    Full Text Available Ventricular arrhythmias and sudden death are common in patients on maintenance hemodialysis (HD. The increase in QT dispersion (QTd on the electrocardiogram (ECG reflects increased tendency for ventricular repolarization that predisposes to arrhythmias. The purpose of the study was to identify the clinical factors that may predict the increased intradialytic QTd and to assess differences in QTd before and after HD. Each of 61 chronic HD patients underwent 12-lead ECG and blood pressure (BP measurement before and every 1 h during a single HD session. The QT intervals were corrected for heart rate using Bazett′s formula. Intradialytic QTd increased in 30 (49% patients. There was no correlation between the increased QTd and the clinical factors including hypertension, pulse pressure, intradialytic hypotension, left ventricular hypertrophy, old myocardial infarct, diabetes mellitus, and nutritional status. The means of QT interval and QTd increased after HD session (from 382 ± 29 to 444 ± 26 ms, P <0.05; and from 74 ± 21 to 114 ± 53 ms, respectively, P <0.05. We conclude that the increased intradialytic QTd could not be predicted by any of the clinical factors evaluated in this study. There was significant difference in the means of QTd before and after HD session.

  6. PROPOSED SIMPLE METHOD FOR ELECTROCARDIOGRAM RECORDING IN FREE-RANGING ASIAN ELEPHANTS (ELEPHAS MAXIMUS).

    Science.gov (United States)

    Chai, Norin; Pouchelon, Jean Louis; Bouvard, Jonathan; Sillero, Leonor Camacho; Huynh, Minh; Segalini, Vincent; Point, Lisa; Croce, Veronica; Rigaux, Goulven; Highwood, Jack; Chetboul, Valérie

    2016-03-01

    Electrocardiography represents a relevant diagnostic tool for detecting cardiac disease in animals. Elephants can present various congenital and acquired cardiovascular diseases. However, few electrophysiologic studies have been reported in captive elephants, mainly due to challenging technical difficulties in obtaining good-quality electrocardiogram (ECG) tracings, and no data are currently available for free-ranging Asian elephants (Elephas maximus). The purpose of this pilot prospective study was to evaluate the feasibility of using a simple method for recording ECG tracings in wild, apparently healthy, unsedated Asian elephants (n = 7) in the standing position. Successful six-lead recordings (I, II, III, aVR, aVL, and aVF) were obtained, with the aVL lead providing the best-quality tracings in most animals. Variables measured in the aVL lead included heart rate, amplitudes and duration of the P waves, QRS complexes, T and U waves, and duration of the PR, QT, and QU intervals. A negative deflection following positive P waves, representative of an atrial repolarization wave (Ta wave), was observed for five out of the seven elephants.

  7. Normal values of the ventricular gradient and QRS-T angle, derived from the pediatric electrocardiogram.

    Science.gov (United States)

    Kamphuis, Vivian P; Blom, Nico A; van Zwet, Erik W; Man, Sumche; Ten Harkel, Arend D J; Maan, Arie C; Swenne, Cees A

    2018-01-06

    Normal values of the mathematically-synthesized vectorcardiogram (VCG) are lacking for children. Therefore, the objective of this study was to assess normal values of the pediatric synthesized VCG (spatial QRS-T angle [SA] and ventricular gradient [VG]). Electrocardiograms (ECGs) of 1263 subjects (0-24 years) with a normal heart were retrospectively selected. VCGs were synthesized by the Kors matrix. Normal values (presented as 2nd and 98th percentiles) were assessed by quantile regression with smoothing by splines. Our results show that heart rate decreased over age, QRS duration increased and QTc interval remained constant. The SA initially decreased and increased again from the age of 8 years. The VG magnitude was relatively stable until the age of 2 years, after which it increased. Normal values of the pediatric ECG and VCG (VG and SA) were established. These normal values could be important for future studies using VG and SA for risk stratification in heart disease in children. Copyright © 2018. Published by Elsevier Inc.

  8. New approach for T-wave end detection on electrocardiogram: Performance in noisy conditions

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    Marañón Reyes Enrique J

    2011-09-01

    Full Text Available Abstract Background The detection of T-wave end points on electrocardiogram (ECG is a basic procedure for ECG processing and analysis. Several methods have been proposed and tested, featuring high accuracy and percentages of correct detection. Nevertheless, their performance in noisy conditions remains an open problem. Methods A new approach and algorithm for T-wave end location based on the computation of Trapezium's areas is proposed and validated (in terms of accuracy and repeatability, using signals from the Physionet QT Database. The performance of the proposed algorithm in noisy conditions has been tested and compared with one of the most used approaches for estimating the T-wave end point: the method based on the threshold on the first derivative. Results The results indicated that the proposed approach based on Trapezium's areas outperformed the baseline method with respect to accuracy and repeatability. Also, the proposed method is more robust to wideband noise. Conclusions The trapezium-based approach has a good performance in noisy conditions and does not rely on any empirical threshold. It is very adequate for use in scenarios where the levels of broadband noise are significant.

  9. Deep ECGNet: An Optimal Deep Learning Framework for Monitoring Mental Stress Using Ultra Short-Term ECG Signals.

    Science.gov (United States)

    Hwang, Bosun; You, Jiwoo; Vaessen, Thomas; Myin-Germeys, Inez; Park, Cheolsoo; Zhang, Byoung-Tak

    2018-02-08

    Stress recognition using electrocardiogram (ECG) signals requires the intractable long-term heart rate variability (HRV) parameter extraction process. This study proposes a novel deep learning framework to recognize the stressful states, the Deep ECGNet, using ultra short-term raw ECG signals without any feature engineering methods. The Deep ECGNet was developed through various experiments and analysis of ECG waveforms. We proposed the optimal recurrent and convolutional neural networks architecture, and also the optimal convolution filter length (related to the P, Q, R, S, and T wave durations of ECG) and pooling length (related to the heart beat period) based on the optimization experiments and analysis on the waveform characteristics of ECG signals. The experiments were also conducted with conventional methods using HRV parameters and frequency features as a benchmark test. The data used in this study were obtained from Kwangwoon University in Korea (13 subjects, Case 1) and KU Leuven University in Belgium (9 subjects, Case 2). Experiments were designed according to various experimental protocols to elicit stressful conditions. The proposed framework to recognize stress conditions, the Deep ECGNet, outperformed the conventional approaches with the highest accuracy of 87.39% for Case 1 and 73.96% for Case 2, respectively, that is, 16.22% and 10.98% improvements compared with those of the conventional HRV method. We proposed an optimal deep learning architecture and its parameters for stress recognition, and the theoretical consideration on how to design the deep learning structure based on the periodic patterns of the raw ECG data. Experimental results in this study have proved that the proposed deep learning model, the Deep ECGNet, is an optimal structure to recognize the stress conditions using ultra short-term ECG data.

  10. The limited utility of screening laboratory tests and electrocardiograms in the management of unintentional asymptomatic pediatric ingestions.

    Science.gov (United States)

    Wang, George Sam; Deakyne, Sara; Bajaj, Lalit; Yin, Shan; Heard, Kennon; Roosevelt, Genie

    2013-07-01

    Suspected ingestions are a common chief complaint to the emergency department although the majority of ingestions by children are insignificant. Assess the utility of screening laboratory tests and Electrocardiograms (ECGs) in unintentional asymptomatic pediatric poisonings. Retrospective chart review at a tertiary care children's hospital and a regional poison center of patients less than 12 years of age using ICD-9 codes from January 2005 through December 2008. Laboratory or ECG results requiring intervention and/or direct treatment, a non-RPC subspecialty consultation, and/or prolonged Emergency Department stay was considered changed management. Five hundred ninety five suspected ingestions met our criteria. The median age was 2.6 years (IQR 1.6, 3.0 years) and 56% were male. One laboratory test or ECG was obtained in 233 patients (39%). Of 24 screening ECGs, 32 complete blood counts and 34 blood gases, none were clinically significant. Fifty-two patients received screening metabolic panels, 3 were abnormal and 2 changed management (anion gap metabolic acidosis with unsuspected salicylate ingestions). None of the 127 (21%) screening acetaminophen levels changed management. Two of sixty-five (13%) screening salicylate levels changed management. Three screening urine toxicology tests on patients with altered mental status were positive without ingestion history. No patient under the age of 12 years with normal vital signs and normal mental status had positive screening tests. Screening laboratory tests and ECGs were of limited utility and rarely changed management despite being ordered in a significant number of patients. Screening tests are rarely indicated in unintentional overdoses in children who are asymptomatic. Copyright © 2013. Published by Elsevier Inc.

  11. Prospective ECG triggering versus low-dose retrospective ECG-gated 128-channel CT coronary angiography: comparison of image quality and radiation dose

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    Feng, Q.; Yin, Y.; Hua, X.; Zhu, R.; Hua, J. [Department of Radiology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); Xu, J., E-mail: xujianr@hotmail.co [Department of Radiology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China)

    2010-10-15

    Aim: To evaluate image quality and radiation dose for 128-detector prospective electrocardiogram (ECG)-gated computed tomography coronary angiography (CTCA) compared with a low-dose retrospective ECG-gated imaging protocol. Materials and methods: Thirty-one and 47 patients suspected of having coronary artery disease were enrolled into groups examined using prospective and low-dose retrospective ECG-gated CT protocols respectively. All examinations were performed on a 128-detector CT system (Definition AS, Siemens Healthcare, Forchheim, Germany). Prospective CTCA was performed using following parameters: tube voltage 100 kV; tube current 205 mAs; centre of acquisition window 70% of the RR interval. The tube current for low-dose retrospective ECG-gated CTCA was full dose during 40-70% of the RR interval and partial dose for the rest of RR interval. The pitch varied between 0.2 and 0.5 depending on heart rate and patient size. Image quality of coronary arteries was evaluated using a four-point grading scale. The signal-to-noise ratios (SNRs) of enhanced arteries and myocardium were also measured, corresponding contrast-to-noise ratios (CNRs) were calculated, and the radiation doses received were recorded. Results: There was a significant difference in the image quality scores between the retrospective and prospective gating protocols (Chi-square = 15.331, p = 0.009). There was no significant difference between the SNRs of the contrasted artery and myocardium in these two groups, but the CNRs were increased in the prospective group. The mean radiation dose of prospective gating group was 2.71 {+-} 0.67 mSv (range, 1.67-3.59 mSv), which was significantly lower than that of the retrospective group (p < 0.001). Conclusion: Prospective CT angiography can achieve lower radiation dose than that of low-dose retrospective CT angiography, with preserved image quality.

  12. A novel algorithm for Bluetooth ECG.

    Science.gov (United States)

    Pandya, Utpal T; Desai, Uday B

    2012-11-01

    In wireless transmission of ECG, data latency will be significant when battery power level and data transmission distance are not maintained. In applications like home monitoring or personalized care, to overcome the joint effect of previous issues of wireless transmission and other ECG measurement noises, a novel filtering strategy is required. Here, a novel algorithm, identified as peak rejection adaptive sampling modified moving average (PRASMMA) algorithm for wireless ECG is introduced. This algorithm first removes error in bit pattern of received data if occurred in wireless transmission and then removes baseline drift. Afterward, a modified moving average is implemented except in the region of each QRS complexes. The algorithm also sets its filtering parameters according to different sampling rate selected for acquisition of signals. To demonstrate the work, a prototyped Bluetooth-based ECG module is used to capture ECG with different sampling rate and in different position of patient. This module transmits ECG wirelessly to Bluetooth-enabled devices where the PRASMMA algorithm is applied on captured ECG. The performance of PRASMMA algorithm is compared with moving average and S-Golay algorithms visually as well as numerically. The results show that the PRASMMA algorithm can significantly improve the ECG reconstruction by efficiently removing the noise and its use can be extended to any parameters where peaks are importance for diagnostic purpose.

  13. Quantification of the first-order high-pass filter's influence on the automatic measurements of the electrocardiogram.

    Science.gov (United States)

    Isaksen, Jonas; Leber, Remo; Schmid, Ramun; Schmid, Hans-Jakob; Generali, Gianluca; Abächerli, Roger

    2017-02-01

    The first-order high-pass filter (AC coupling) has previously been shown to affect the ECG for higher cut-off frequencies. We seek to find a systematic deviation in computer measurements of the electrocardiogram when the AC coupling with a 0.05 Hz first-order high-pass filter is used. The standard 12-lead electrocardiogram from 1248 patients and the automated measurements of their DC and AC coupled version were used. We expect a large unipolar QRS-complex to produce a deviation in the opposite direction in the ST-segment. We found a strong correlation between the QRS integral and the offset throughout the ST-segment. The coefficient for J amplitude deviation was found to be -0.277 µV/(µV⋅s). Potential dangerous alterations to the diagnostically important ST-segment were found. Medical professionals and software developers for electrocardiogram interpretation programs should be aware of such high-pass filter effects since they could be misinterpreted as pathophysiology or some pathophysiology could be masked by these effects. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  14. ECG in preparticipation screening of young athletes

    Directory of Open Access Journals (Sweden)

    Višnjevac Danilo

    2015-01-01

    Full Text Available Introduction: The aim of the ECG in preparticipation screening of young athletes is detection of potential disorders in asymptomatic young athletes. Objective: The objective of the study was to determine the freqency and type of ECG changes observed during preparticipation screening of young athletes. Method: The research included analysis of ECG tests recorded during the regular preparticipation screening of 219 young athletes, aged from 9 to 19 years, predominantly male, who were engaged in 7 different sport disciplines. Standard ECG was recorded at least 24 hours after strenuous physical activity. ECG analysis was performed according to the European Society of Cardiology (ESC recommendations for the interpretation of 12-lead ECG in the athletes, with corrections related to the inversion of T wave. Results: ECG was perfectly normal in 103 (47%, and ECG changes were noticed in 116 (53% of the athletes. In 51.6% of examined athletes, ECG changes were of the common type, reflecting adaptation of the heart to regular exercises, and only in 1,4% athletes vwere founded ECG changes that are not consistent with training. The most common (32% of the total examinees was incomplete right bundle branch block (RBBB. Sinus bradycardia was present in 12,8% of the athletes, and early repolarization at 7,8%. T wave inversion without clinical significance was observed in 4,1% of athlets. Isolated increase in QRS complex voltage was observed in 3,6%, while the first degree AV block was present in 0,5% of the athletes. ECG changes unrelated to training were recorded in 1,4% of athletes. Significant T wave inversion was observed in 0,9% and pre-excitation (Wolf-Parkinson-White syndrom in 0,5% of the athletes. Conclusion: Preparticipation screening ECG test revealed ECG changes in 51,6% of young athletes. The vast majority of changes are of common, physiological type, that neither requires further investigation, nor termination of active participation in sports. In

  15. Comparison of three artificial models of the magnetohydrodynamic effect on the electrocardiogram.

    Science.gov (United States)

    Oster, Julien; Llinares, Raul; Payne, Stephen; Tse, Zion Tsz Ho; Schmidt, Ehud Jeruham; Clifford, Gari D

    2015-01-01

    The electrocardiogram (ECG) is often acquired during magnetic resonance imaging (MRI), but its analysis is restricted by the presence of a strong artefact, called magnetohydrodynamic (MHD) effect. MHD effect is induced by the flow of electrically charged particles in the blood perpendicular to the static magnetic field, which creates a potential of the order of magnitude of the ECG and temporally coincident with the repolarisation period. In this study, a new MHD model is proposed by using MRI-based 4D blood flow measurements made across the aortic arch. The model is extended to several cardiac cycles to allow the simulation of a realistic ECG acquisition during MRI examination and the quality assessment of MHD suppression techniques. A comparison of two existing models, based, respectively, on an analytical solution and on a numerical method-based solution of the fluids dynamics problem, is made with the proposed model and with an estimate of the MHD voltage observed during a real MRI scan. Results indicate a moderate agreement between the proposed model and the estimated MHD model for most leads, with an average correlation factor of 0.47. However, the results demonstrate that the proposed model provides a closer approximation to the observed MHD effects and a better depiction of the complexity of the MHD effect compared with the previously published models, with an improved correlation (+5%), coefficient of determination (+22%) and fraction of energy (+1%) compared with the best previous model. The source code will be made freely available under an open source licence to facilitate collaboration and allow more rapid development of more accurate models of the MHD effect.

  16. Dispersion of the corrected QT interval in the electrocardiogram of the ex-prisoners of war.

    Science.gov (United States)

    Corović, Naima; Duraković, Zijad; Misigoj-Duraković, Marjeta

    2003-04-01

    The study of electrocardiograms (ECGs) was performed in a subgroup of 181 men, ex-prisoners of war with mean age 35.8+/-11.0 years and mean duration of imprisonment 164.5+/-87.1 days, chosen at random from the total sample of released prisoners (N=1458). The control group was pair-matched. The analysis of ECGs was done according to the Minnesota code, and Bazett's formula gave the values of the corrected QT interval (QT(c)). The dispersion of the QT(c) interval is determined by the difference between the longest and the shortest measured QT(c) interval in each ECG lead. The results of descriptive statistics in the group of ex-prisoners showed the range of QT(c) dispersion of 8.0-122.0 ms (mean 52.4+/-21.6 ms), while in the control group the range was 6.0-72.0 ms (mean 30.4+/-13.8 ms) (df=360, t=11.536; Pprisoners and 30.4% controls, while a QT(c) interval over 480.0 ms had 19.3% ex-prisoners and 1.10% controls (Pprisoners group, the QT(c) dispersion over 50 ms was present in 51.4%; of those, a dispersion of 95 ms and more was found in 3.9%, while in the controls a QT(c) dispersion over 50 ms was found in 8.3%, but a dispersion of 95 ms and more was not recorded (Pprisoners versus controls (P<0.001). In conclusion, persons exposed to long-term maltreatment in detention camps have significantly greater QT(c) dispersion, as well as a higher relative risk of prolonged QT(c) interval and greater QT(c) dispersion than a control group.

  17. E-learning and near-peer teaching in electrocardiogram education: a randomised trial.

    Science.gov (United States)

    Davies, Andrew; Macleod, Rachael; Bennett-Britton, Ian; McElnay, Philip; Bakhbakhi, Danya; Sansom, Jane

    2016-06-01

    Near-peer teaching and electronic learning (e-learning) are two effective modern teaching styles. Near-peer sessions provide a supportive learning environment that benefits both the students and the tutor. E-learning resources are flexible and easily distributed. Careful construction and regular editing can ensure that students receive all of the essential material. The aim of this study is to compare the efficacy of e-learning and near-peer teaching during the pre-clinical medical curriculum. Thirty-nine second-year medical students were consented and randomised into two groups. Each group received teaching on electrocardiogram (ECG) interpretation from a predefined syllabus. Eighteen students completed an e-learning module and 21 students attended a near-peer tutorial. Students were asked to complete a multiple-choice exam, scored out of 50. Each student rated their confidence in ECG interpretation before and after their allocated teaching session. The near-peer group (84%) demonstrated a significantly higher performance than the e-learning group (74.5%) on the final assessment (p = 0.002). Prior to the teaching, the students' mean confidence scores were 3/10 in both the near-peer and e-learning groups (0, poor; 10, excellent). These increased to 6/10 in both cases following the teaching session. Both teaching styles were well received by students and improved their confidence in ECG interpretation. Near-peer teaching led to superior scores in our final assessment. Given the congested nature of the modern medical curriculum, direct comparison of the efficacy of these methods may aid course design. The aim of this study is to compare the efficacy of e-learning and near-peer teaching. © 2015 John Wiley & Sons Ltd.

  18. Effects of age, sex and body build on ECG QRS voltages in Nigerians.

    Science.gov (United States)

    Odia, O J

    1990-09-01

    The effects of age, sex and body build on ECG QRS voltages were studied in Nigerian Africans. Eighty-nine subjects consisted of 35 hypertensives, 20 patients with mitral incompetence and/or aortic incompetence and 34 healthy subjects. QRS voltage summations were made where necessary to reflect available ECG voltage criteria for left ventricular hypertrophy. Pearson's correlation coefficients were then determined between the ECG QRS voltage values and age, height, weight and body surface area in each group of subjects with the aid of an IBM 370/135 computer utilising SPSS programs. The study showed that ECG QRS voltages in our Nigerian African subjects significantly decreased with age and that men had higher voltages than women. Weight had variable effects on ECG QRS voltages. It is suggested that correction factors for age, sex and weight be determined by ECG laboratories for their population groups with the use of multiple regression analysis in order to improve on the widely used ECG QRS voltage criteria for left ventricular hypertrophy.

  19. ECG response of koalas to tourists proximity: a preliminary study.

    Directory of Open Access Journals (Sweden)

    Yan Ropert-Coudert

    Full Text Available Koalas operate on a tight energy budget and, thus, may not always display behavioral avoidance reaction when placed in a stressful condition. We investigated the physiological response of captive koalas Phascolarctos cinereus in a conservation centre to the presence of tourists walking through their habitat. We compared, using animal-attached data-recorders, the electrocardiogram activity of female koalas in contact with tourists and in a human-free area. One of the koalas in the tourist zone presented elevated heart rate values and variability throughout the recording period. The remaining female in the exhibit area showed a higher field resting heart rates during the daytime than that in the isolated area. In the evening, heart rate profiles changed drastically and both the koalas in the exhibit and in the tourist-free zones displayed similar field resting heart rates, which were lower than those during the day. In parallel, the autonomic nervous systems of these two individuals evolved from sympathetic-dominant during the day to parasympathetic-dominant in the evening. Our results report ECG of free-living koalas for the first time. Although they are preliminary due to the difficulty of having sufficient samples of animals of the same sex and age, our results stress out the importance of studies investigating the physiological reaction of animals to tourists.

  20. ECG response of koalas to tourists proximity: a preliminary study.

    Science.gov (United States)

    Ropert-Coudert, Yan; Brooks, Lisa; Yamamoto, Maki; Kato, Akiko

    2009-10-12

    Koalas operate on a tight energy budget and, thus, may not always display behavioral avoidance reaction when placed in a stressful condition. We investigated the physiological response of captive koalas Phascolarctos cinereus in a conservation centre to the presence of tourists walking through their habitat. We compared, using animal-attached data-recorders, the electrocardiogram activity of female koalas in contact with tourists and in a human-free area. One of the koalas in the tourist zone presented elevated heart rate values and variability throughout the recording period. The remaining female in the exhibit area showed a higher field resting heart rates during the daytime than that in the isolated area. In the evening, heart rate profiles changed drastically and both the koalas in the exhibit and in the tourist-free zones displayed similar field resting heart rates, which were lower than those during the day. In parallel, the autonomic nervous systems of these two individuals evolved from sympathetic-dominant during the day to parasympathetic-dominant in the evening. Our results report ECG of free-living koalas for the first time. Although they are preliminary due to the difficulty of having sufficient samples of animals of the same sex and age, our results stress out the importance of studies investigating the physiological reaction of animals to tourists.

  1. A QRS Detection and R Point Recognition Method for Wearable Single-Lead ECG Devices.

    Science.gov (United States)

    Chen, Chieh-Li; Chuang, Chun-Te

    2017-08-26

    In the new-generation wearable Electrocardiogram (ECG) system, signal processing with low power consumption is required to transmit data when detecting dangerous rhythms and to record signals when detecting abnormal rhythms. The QRS complex is a combination of three of the graphic deflection seen on a typical ECG. This study proposes a real-time QRS detection and R point recognition method with low computational complexity while maintaining a high accuracy. The enhancement of QRS segments and restraining of P and T waves are carried out by the proposed ECG signal transformation, which also leads to the elimination of baseline wandering. In this study, the QRS fiducial point is determined based on the detected crests and troughs of the transformed signal. Subsequently, the R point can be recognized based on four QRS waveform templates and preliminary heart rhythm classification can be also achieved at the same time. The performance of the proposed approach is demonstrated using the benchmark of the MIT-BIH Arrhythmia Database, where the QRS detected sensitivity (Se) and positive prediction (+P) are 99.82% and 99.81%, respectively. The result reveals the approach's advantage of low computational complexity, as well as the feasibility of the real-time application on a mobile phone and an embedded system.

  2. An efficient coding algorithm for the compression of ECG signals using the wavelet transform.

    Science.gov (United States)

    Rajoub, Bashar A

    2002-04-01

    A wavelet-based electrocardiogram (ECG) data compression algorithm is proposed in this paper. The ECG signal is first preprocessed, the discrete wavelet transform (DWT) is then applied to the preprocessed signal. Preprocessing guarantees that the magnitudes of the wavelet coefficients be less than one, and reduces the reconstruction errors near both ends of the compressed signal. The DWT coefficients are divided into three groups, each group is thresholded using a threshold based on a desired energy packing efficiency. A binary significance map is then generated by scanning the wavelet decomposition coefficients and outputting a binary one if the scanned coefficient is significant, and a binary zero if it is insignificant. Compression is achieved by 1) using a variable length code based on run length encoding to compress the significance map and 2) using direct binary representation for representing the significant coefficients. The ability of the coding algorithm to compress ECG signals is investigated, the results were obtained by compressing and decompressing the test signals. The proposed algorithm is compared with direct-based and wavelet-based compression algorithms and showed superior performance. A compression ratio of 24:1 was achieved for MIT-BIH record 117 with a percent root mean square difference as low as 1.08%.

  3. Mobile Cloud-Computing-Based Healthcare Service by Noncontact ECG Monitoring

    Directory of Open Access Journals (Sweden)

    Ee-May Fong

    2013-12-01

    Full Text Available Noncontact electrocardiogram (ECG measurement technique has gained popularity these days owing to its noninvasive features and convenience in daily life use. This paper presents mobile cloud computing for a healthcare system where a noncontact ECG measurement method is employed to capture biomedical signals from users. Healthcare service is provided to continuously collect biomedical signals from multiple locations. To observe and analyze the ECG signals in real time, a mobile device is used as a mobile monitoring terminal. In addition, a personalized healthcare assistant is installed on the mobile device; several healthcare features such as health status summaries, medication QR code scanning, and reminders are integrated into the mobile application. Health data are being synchronized into the healthcare cloud computing service (Web server system and Web server dataset to ensure a seamless healthcare monitoring system and anytime and anywhere coverage of network connection is available. Together with a Web page application, medical data are easily accessed by medical professionals or family members. Web page performance evaluation was conducted to ensure minimal Web server latency. The system demonstrates better availability of off-site and up-to-the-minute patient data, which can help detect health problems early and keep elderly patients out of the emergency room, thus providing a better and more comprehensive healthcare cloud computing service.

  4. Mobile cloud-computing-based healthcare service by noncontact ECG monitoring.

    Science.gov (United States)

    Fong, Ee-May; Chung, Wan-Young

    2013-12-02

    Noncontact electrocardiogram (ECG) measurement technique has gained popularity these days owing to its noninvasive features and convenience in daily life use. This paper presents mobile cloud computing for a healthcare system where a noncontact ECG measurement method is employed to capture biomedical signals from users. Healthcare service is provided to continuously collect biomedical signals from multiple locations. To observe and analyze the ECG signals in real time, a mobile device is used as a mobile monitoring terminal. In addition, a personalized healthcare assistant is installed on the mobile device; several healthcare features such as health status summaries, medication QR code scanning, and reminders are integrated into the mobile application. Health data are being synchronized into the healthcare cloud computing service (Web server system and Web server dataset) to ensure a seamless healthcare monitoring system and anytime and anywhere coverage of network connection is available. Together with a Web page application, medical data are easily accessed by medical professionals or family members. Web page performance evaluation was conducted to ensure minimal Web server latency. The system demonstrates better availability of off-site and up-to-the-minute patient data, which can help detect health problems early and keep elderly patients out of the emergency room, thus providing a better and more comprehensive healthcare cloud computing service.

  5. Block sparsity-based joint compressed sensing recovery of multi-channel ECG signals.

    Science.gov (United States)

    Singh, Anurag; Dandapat, Samarendra

    2017-04-01

    In recent years, compressed sensing (CS) has emerged as an effective alternative to conventional wavelet based data compression techniques. This is due to its simple and energy-efficient data reduction procedure, which makes it suitable for resource-constrained wireless body area network (WBAN)-enabled electrocardiogram (ECG) telemonitoring applications. Both spatial and temporal correlations exist simultaneously in multi-channel ECG (MECG) signals. Exploitation of both types of correlations is very important in CS-based ECG telemonitoring systems for better performance. However, most of the existing CS-based works exploit either of the correlations, which results in a suboptimal performance. In this work, within a CS framework, the authors propose to exploit both types of correlations simultaneously using a sparse Bayesian learning-based approach. A spatiotemporal sparse model is employed for joint compression/reconstruction of MECG signals. Discrete wavelets transform domain block sparsity of MECG signals is exploited for simultaneous reconstruction of all the channels. Performance evaluations using Physikalisch-Technische Bundesanstalt MECG diagnostic database show a significant gain in the diagnostic reconstruction quality of the MECG signals compared with the state-of-the art techniques at reduced number of measurements. Low measurement requirement may lead to significant savings in the energy-cost of the existing CS-based WBAN systems.

  6. Wireless ECG and PCG Portable Telemedicine Kit for Rural Areas of Colombia

    Directory of Open Access Journals (Sweden)

    Miguel Jimeno

    2014-07-01

    Full Text Available Telemedicine is always a popular topic thanks to the constants advancements of technology. The focus on development of new devices has been mainly on decreasing size to increase portability. Our research focused on improving functionality but not giving up on portability and cost. In this paper we are presenting the first prototype device that measures 4-leads electrocardiogram (ECG and phonocardiogram (PCG signals with low cost, high portability and wireless connectivity features in mind. We designed and developed a prototype that measures ECG using a standard ECG cable; we designed and developed a digital stethoscope prototype and also the necessary hardware for both medical signals to be transmitted through Bluetooth to a computer. We present here the hardware design, a new communication protocol for transmission of both signals from the device to the computer, and the software system to enable remote consultations. We designed the prototype with the main purpose of using low cost parts without sacrificing functionality, with the purpose of using it in remote zones of the Caribbean coast of Colombia. We show open issues and prepare a field implementation of the kit in the target zone.

  7. ECG Signal Denoising and QRS Complex Detection by Wavelet Transform Based Thresholding

    Directory of Open Access Journals (Sweden)

    Swati BANERJEE

    2010-08-01

    Full Text Available Biomedical signals like heart waves commonly change their statistical property over time and are highly non stationary signals. For the analysis of this kind of signals wavelet transform is a powerful tool. Electrocardiogram (ECG is one of the most widely used diagnostic tools for heart disease. Automatic detection of R peaks in a QRS complex is a fundamental requirement for automatic disease identification. This paper presents a novel algorithm and its implementation details for denoising an ECG signal along with accurate detection of R peaks and hence the QRS complex using Discrete Wavelet Transform (DWT where db6 is selected as the mother wavelet for analysis as it is found to be most similar to the morphology of QRS complexes. Decomposition and selective reconstruction by elimination of higher scale details from the signal, denoises it considerably. Thresholding along with slope inversion method is used for detection of QRS complex. The performance of the system is validated using the 12-lead ECG recordings collected from physionet PTB diagnostic database giving a sensitivity of 99.4 %.

  8. Design of Secure ECG-Based Biometric Authentication in Body Area Sensor Networks.

    Science.gov (United States)

    Peter, Steffen; Reddy, Bhanu Pratap; Momtaz, Farshad; Givargis, Tony

    2016-04-22

    Body area sensor networks (BANs) utilize wireless communicating sensor nodes attached to a human body for convenience, safety, and health applications. Physiological characteristics of the body, such as the heart rate or Electrocardiogram (ECG) signals, are promising means to simplify the setup process and to improve security of BANs. This paper describes the design and implementation steps required to realize an ECG-based authentication protocol to identify sensor nodes attached to the same human body. Therefore, the first part of the paper addresses the design of a body-area sensor system, including the hardware setup, analogue and digital signal processing, and required ECG feature detection techniques. A model-based design flow is applied, and strengths and limitations of each design step are discussed. Real-world measured data originating from the implemented sensor system are then used to set up and parametrize a novel physiological authentication protocol for BANs. The authentication protocol utilizes statistical properties of expected and detected deviations to limit the number of false positive and false negative authentication attempts. The result of the described holistic design effort is the first practical implementation of biometric authentication in BANs that reflects timing and data uncertainties in the physical and cyber parts of the system.

  9. Design of Secure ECG-Based Biometric Authentication in Body Area Sensor Networks

    Directory of Open Access Journals (Sweden)

    Steffen Peter

    2016-04-01

    Full Text Available Body area sensor networks (BANs utilize wireless communicating sensor nodes attached to a human body for convenience, safety, and health applications. Physiological characteristics of the body, such as the heart rate or Electrocardiogram (ECG signals, are promising means to simplify the setup process and to improve security of BANs. This paper describes the design and implementation steps required to realize an ECG-based authentication protocol to identify sensor nodes attached to the same human body. Therefore, the first part of the paper addresses the design of a body-area sensor system, including the hardware setup, analogue and digital signal processing, and required ECG feature detection techniques. A model-based design flow is applied, and strengths and limitations of each design step are discussed. Real-world measured data originating from the implemented sensor system are then used to set up and parametrize a novel physiological authentication protocol for BANs. The authentication protocol utilizes statistical properties of expected and detected deviations to limit the number of false positive and false negative authentication attempts. The result of the described holistic design effort is the first practical implementation of biometric authentication in BANs that reflects timing and data uncertainties in the physical and cyber parts of the system.

  10. Graphite Based Electrode for ECG Monitoring: Evaluation under Freshwater and Saltwater Conditions

    Directory of Open Access Journals (Sweden)

    Tharoeun Thap

    2016-04-01

    Full Text Available We proposed new electrodes that are applicable for electrocardiogram (ECG monitoring under freshwater- and saltwater-immersion conditions. Our proposed electrodes are made of graphite pencil lead (GPL, a general-purpose writing pencil. We have fabricated two types of electrode: a pencil lead solid type (PLS electrode and a pencil lead powder type (PLP electrode. In order to assess the qualities of the PLS and PLP electrodes, we compared their performance with that of a commercial Ag/AgCl electrode, under a total of seven different conditions: dry, freshwater immersion with/without movement, post-freshwater wet condition, saltwater immersion with/without movement, and post-saltwater wet condition. In both dry and post-freshwater wet conditions, all ECG-recorded PQRST waves were clearly discernible, with all types of electrodes, Ag/AgCl, PLS, and PLP. On the other hand, under the freshwater- and saltwater-immersion conditions with/without movement, as well as post-saltwater wet conditions, we found that the proposed PLS and PLP electrodes provided better ECG waveform quality, with significant statistical differences compared with the quality provided by Ag/AgCl electrodes.

  11. A comparative study of two techniques (electrocardiogram- and landmark-guided for correct depth of the central venous catheter placement in paediatric patients undergoing elective cardiovascular surgery

    Directory of Open Access Journals (Sweden)

    Neeraj Kumar Barnwal

    2016-01-01

    Full Text Available Background and Aims: The complications of central venous catheterisation can be minimized by ensuring catheter tip placement just above the superior vena cava-right atrium junction. We aimed to compare two methods, using an electrocardiogram (ECG or landmark as guides, for assessing correct depth of central venous catheter (CVC placement. Methods: In a prospective randomised study of sixty patients of <12 years of age, thirty patients each were allotted randomly to two groups (ECG and landmark. After induction, central venous catheterisation was performed by either of the two techniques and position of CVC tip was compared in post-operative chest X-ray with respect to carina. Unpaired t-test was used for quantitative data and Chi-square test was used for qualitative data. Results: In ECG group, positions of CVC tip were above carina in 12, at carina in 9 and below carina in 9 patients. In landmark group, the positions of CVC tips were above carina in 10, at carina in 4 and below carina in 16 patients. Mean distance of CVC tip in ECG group was 0.34 ± 0.23 cm and 0.66 ± 0.35 cm in landmark group (P = 0.0001. Complications occurred in one patient in ECG group and in nine patients in landmark group (P = 0.0056. Conclusion: Overall, landmark-guided technique was comparable with ECG technique. ECG-guided technique was more precise for CVC tip placement closer to carina. The incidence of complications was more in the landmark group.

  12. The Role of Post-Resuscitation Electrocardiogram in Patients With ST-Segment Changes in the Immediate Post-Cardiac Arrest Period.

    Science.gov (United States)

    Kim, Youn-Jung; Min, Sun-Yang; Lee, Dong Hun; Lee, Byung Kook; Jeung, Kyung Woon; Lee, Hui Jai; Shin, Jonghwan; Ko, Byuk Sung; Ahn, Shin; Nam, Gi-Byoung; Lim, Kyoung Soo; Kim, Won Young

    2017-03-13

    The authors aimed to evaluate the role of post-resuscitation electrocardiogram (ECG) in patients showing significant ST-segment changes on the initial ECG and to provide useful diagnostic indicators for physicians to determine in which out-of-hospital cardiac arrest (OHCA) patients brain computed tomography (CT) should be performed before emergency coronary angiography. The usefulness of immediate brain CT and ECG for all resuscitated patients with nontraumatic OHCA remains controversial. Between January 2010 and December 2014, 1,088 consecutive adult nontraumatic patients with return of spontaneous circulation who visited the emergency department of 3 tertiary care hospitals were enrolled. After excluding 245 patients with obvious extracardiac causes, 200 patients were finally included. The patients were categorized into 2 groups: those with ST-segment changes with spontaneous subarachnoid hemorrhage (SAH) (n = 50) and those with OHCA of suspected cardiac origin group (n = 150). The combination of 4 ECG characteristics including narrow QRS (<120 ms), atrial fibrillation, prolonged QTc interval (≥460 ms), and ≥4 ST-segment depressions had a 66.0% sensitivity, 80.0% specificity, 52.4% positive predictive value, and 87.6% negative predictive value for predicting SAH. The area under the receiver-operating characteristic curves in the post-resuscitation ECG findings was 0.816 for SAH. SAH was observed in a substantial number of OHCA survivors (25.0%) with significant ST-segment changes on post-resuscitation ECG. Resuscitated patients with narrow QRS complex and any 2 ECG findings of atrial fibrillation, QTc interval prolongation, or ≥4 ST-segment depressions may help identify patients who need brain CT as the next diagnostic work-up. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  13. Electrocardiograms of Children and Adolescents Practicing Non-competitive Sports: Normal Limits and Abnormal Findings in a Large European Cohort Evaluated by Telecardiology.

    Science.gov (United States)

    Molinari, Giuseppe; Brunetti, Natale Daniele; Biasco, Luigi; Squarcia, Sandro; Cristoforetti, Yvonne; Bennicelli, Riccardo; Del Vecchio, Cecilia; Viacava, Cecilia; Giustetto, Carla; Gaita, Fiorenzo

    2017-03-01

    The objective of this study was to derive normal electrocardiographic values and to report the abnormal findings in a large contemporary European cohort of physically active children and young adolescents. In a 3-month period, data derived from subjects aged between 3 and 14 years and referred to the Telecardiology Centre (Genoa, Italy) for electrocardiogram (ECG) evaluation as pre-participation screening for non-competitive sports were analyzed. A total of 2060 ECGs were recorded. Of those, 1962 did not show any morphological abnormality and were used to derive normality ranges for heart rate, PR interval, QRS duration, corrected QT interval, and voltage of R wave as measured in V1 according to age and sex. Findings and clinical implications of the 98 ECGs with abnormal findings were also reported. Abnormal ECG findings were not as uncommon as expected in this population, being manifest in about 5 % of subjects. However, major ECG anomalies (diffuse negative T-waves, pre-excitation) were present in just ten subjects (0.5 %). Lower mean heart rate values (from 90-100 bpm at 3 years of age to 80-85 bpm at 14 years of age) and lower rates of the prevalence of negative T-waves in the V3 lead (from 55-60 % at 3 years of age to 8-10 % at 14 years of age) were observed with increasing age. This is the first work reporting derived normal limits and abnormal ECG findings in a large contemporary European cohort of children and adolescents aged 3-14 years practicing non-competitive sports. Clear pathological alterations are extremely uncommon, deserving, when encountered, additional examinations. Even in a physically active population, the common features of an adult athlete's ECG are absent.

  14. Improvement of Door-to-Electrocardiogram Time Using the First-Nurse Role in the ED Setting.

    Science.gov (United States)

    Stanfield, Laura

    2018-02-04

    This quality improvement project compared door-to-electrocardiogram (ECG) times for patients presenting with symptoms suggestive of acute coronary syndrome within a community hospital emergency department before and after first-nurse (emergency nurse stationed in the ED waiting room) training. Door-to-ECG time was compared before and after the educational intervention using Acute Coronary Treatment and Intervention Outcomes Network (ACTION) registry data reported by the facility. Statistical significance was not achieved using a 2-group t-test. However, when comparing monthly means, data trend lines showed favorable improvement for door-to-ECG time after the intervention. Limitations included using only those patients in the ACTION registry and not accounting for RN turnover with first-nurse education. Future studies should focus on all patients presenting with symptoms of acute coronary syndrome as well as other patients presenting with time-sensitive needs to determine the efficacy of the first-nurse role. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. An Energy efficient application specific integrated circuit for electrocardiogram feature detection and its potential for ambulatory cardiovascular disease detection.

    Science.gov (United States)

    Jain, Sanjeev Kumar; Bhaumik, Basabi

    2016-03-01

    A novel algorithm based on forward search is developed for real-time electrocardiogram (ECG) signal processing and implemented in application specific integrated circuit (ASIC) for QRS complex related cardiovascular disease diagnosis. The authors have evaluated their algorithm using MIT-BIH database and achieve sensitivity of 99.86% and specificity of 99.93% for QRS complex peak detection. In this Letter, Physionet PTB diagnostic ECG database is used for QRS complex related disease detection. An ASIC for cardiovascular disease detection is fabricated using 130-nm CMOS high-speed process technology. The area of the ASIC is 0.5 mm(2). The power dissipation is 1.73 μW at the operating frequency of 1 kHz with a supply voltage of 0.6 V. The output from the ASIC is fed to their Android application that generates diagnostic report and can be sent to a cardiologist through email. Their ASIC result shows average failed detection rate of 0.16% for six leads data of 290 patients in PTB diagnostic ECG database. They also have implemented a low-leakage version of their ASIC. The ASIC dissipates only 45 pJ with a supply voltage of 0.9 V. Their proposed ASIC is most suitable for energy efficient telemetry cardiovascular disease detection system.

  16. Improving ECG Services at a Children’s Hospital: Implementation of a Digital ECG System

    Directory of Open Access Journals (Sweden)

    Frank A. Osei

    2015-01-01

    Full Text Available Background. The use of digital ECG software and services is becoming common. We hypothesized that the introduction of a completely digital ECG system would increase the volume of ECGs interpreted at our children’s hospital. Methods. As part of a hospital wide quality improvement initiative, a digital ECG service (MUSE, GE was implemented at the Children’s Hospital at Montefiore in June 2012. The total volume of ECGs performed in the first 6 months of the digital ECG era was compared to 18 months of the predigital era. Predigital and postdigital data were compared via t-tests. Results. The mean ECGs interpreted per month were 53 ± 16 in the predigital era and 216 ± 37 in the postdigital era (p<0.001, a fourfold increase in ECG volume after introduction of the digital system. There was no significant change in inpatient or outpatient service volume during that time. The mean billing time decreased from 21 ± 27 days in the postdigital era to 12 ± 5 days in the postdigital era (p<0.001. Conclusion. Implementation of a digital ECG system increased the volume of ECGs officially interpreted and reported.

  17. Analysis of electrocardiogram in chronic obstructive pulmonary disease patients.

    Science.gov (United States)

    Lazović, Biljana; Svenda, Mirjana Zlatković; Mazić, Sanja; Stajić, Zoran; Delić, Marina

    2013-01-01

    Chronic obstructive pulmonary disease is the fourth leading cause of mortality worldwide. It is defined as a persistent airflow limitation usually progressive and not fully reversible to treatment. The diagnosis of chronic obstructive pulmonary disease and severity of disease is confirmed by spirometry. Chronic obstructive pulmonary disease produces electrical changes in the heart which shows characteristic electrocardiogram pattern. The aim of this study was to observe and evaluate diagnostic values of electrocardiogram changes in chronic obstructive pulmonary disease patients with no other comorbidity. We analyzed 110 electrocardiogram findings in clinically stable chronic obstructive pulmonary disease patients and evaluated the forced expiratory volume in the first second, ratio of forces expiratory volume in the first second to the fixed vital capacity, chest radiographs and electrocardiogram changes such as p wave height, QRS axis and voltage, right bundle branch block, left bundle branch block, right ventricular hypertrophy, T wave inversion in leads V1-V3, S1S2S3 syndrome, transition zone in praecordial lead and QT interval. We found electrocardiogram changes in 64% patients, while 36% had normal electrocardiogram. The most frequent electrocardiogram changes observed were transition zone (76.36%) low QRS (50%) and p pulmonale (14.54%). Left axis deviation was observed in 27.27% patients. Diagnostic values of electrocardiogram in patients with chronic obstructive pulmonary disease suggest that chronic obstructive pulmonary disease patients should be screened electrocardiographically in addition to other clinical investigations.

  18. Pulse arrival time (PAT) measurement based on arm ECG and finger PPG signals - comparison of PPG feature detection methods for PAT calculation.

    Science.gov (United States)

    Rajala, Satu; Ahmaniemi, Teemu; Lindholm, Harri; Taipalus, Tapio

    2017-07-01

    In this study, pulse arrival time (PAT) was measured using a simple measurement setup consisting of arm electrocardiogram (ECG) and finger photoplethysmogram (PPG). Four methods to calculate PAT from the measured signals were evaluated. PAT was calculated as the time delay between ECG R peak and one of the following points in the PPG waveform: peak (maximum value of PPG waveform), foot (minimum value of PPG waveform), dpeak (maximum value of the first derivative of PPG waveform) and ddpeak (maximum value of the second derivative of PPG waveform). In addition to PAT calculation, pulse period (PP) intervals based on the detected features were determined and compared to RR intervals derived from ECG signal. Based on the results obtained here, the most promising method to be used in PAT or PP calculation seems to be the dpeak detection method.

  19. Classification of acute stress using linear and non-linear heart rate variability analysis derived from sternal ECG

    DEFF Research Database (Denmark)

    Tanev, George; Saadi, Dorthe Bodholt; Hoppe, Karsten

    2014-01-01

    Chronic stress detection is an important factor in predicting and reducing the risk of cardiovascular disease. This work is a pilot study with a focus on developing a method for detecting short-term psychophysiological changes through heart rate variability (HRV) features. The purpose of this pilot...... features from electrocardiograms (ECG) acquired by the wireless wearable ePatch® recorder. The highest recognition rates were acquired for the neutral stage (90%), the acute stress stage (80%) and the baseline stage (80%) by sample entropy, detrended fluctuation analysis and normalized high frequency...

  20. Micro EEG/ECG signal’s chopper-stabilization amplifying chip for novel dry-contact electrode

    Science.gov (United States)

    Sun, Jianhui; Wang, Chunxing; Wang, Gongtang; Wang, Jinhui; Hua, Qing; Cheng, Chuanfu; Cai, Xinxia; Yin, Tao; Yu, Yang; Yang, Haigang; Li, Dengwang

    2017-02-01

    Facing the body’s EEG (electroencephalograph, 0.5-100 Hz, 5-100 μV) and ECG’s (electrocardiogram, ECG’s waves are real-time displayed with the PC-Labview. The proposed chopper system is a unified EEG/ECG signal’s detection instrument and has a critical real application value. Project supported by the National Natural Science Foundation of China (Nos. 61527815, 31500800, 61501426, 61471342), the National Key Basic Research Plan (No. 2014CB744600), the Beijing Science and Technology Plan (No. Z141100000214002), and the Chinese Academy of Sciences’ Key Project (No. KJZD-EW-L11-2).

  1. Electrocardiogram classification using delay differential equations.

    Science.gov (United States)

    Lainscsek, Claudia; Sejnowski, Terrence J

    2013-06-01

    Time series analysis with nonlinear delay differential equations (DDEs) reveals nonlinear as well as spectral properties of the underlying dynamical system. Here, global DDE models were used to analyze 5 min data segments of electrocardiographic (ECG) recordings in order to capture distinguishing features for different heart conditions such as normal heart beat, congestive heart failure, and atrial fibrillation. The number of terms and delays in the model as well as the order of nonlinearity of the model have to be selected that are the most discriminative. The DDE model form that best separates the three classes of data was chosen by exhaustive search up to third order polynomials. Such an approach can provide deep insight into the nature of the data since linear terms of a DDE correspond to the main time-scales in the signal and the nonlinear terms in the DDE are related to nonlinear couplings between the harmonic signal parts. The DDEs were able to detect atrial fibrillation with an accuracy of 72%, congestive heart failure with an accuracy of 88%, and normal heart beat with an accuracy of 97% from 5 min of ECG, a much shorter time interval than required to achieve comparable performance with other methods.

  2. Ventricular beat detection in single channel electrocardiograms.

    Science.gov (United States)

    Dotsinsky, Ivan A; Stoyanov, Todor V

    2004-01-29

    Detection of QRS complexes and other types of ventricular beats is a basic component of ECG analysis. Many algorithms have been proposed and used because of the waves' shape diversity. Detection in a single channel ECG is important for several applications, such as in defibrillators and specialized monitors. The developed heuristic algorithm for ventricular beat detection includes two main criteria. The first of them is based on steep edges and sharp peaks evaluation and classifies normal QRS complexes in real time. The second criterion identifies ectopic beats by occurrence of biphasic wave. It is modified to work with a delay of one RR interval in case of long RR intervals. Other algorithm branches classify already detected QRS complexes as ectopic beats if a set of wave parameters is encountered or the ratio of latest two RR intervals RRi-1/RRi is less than 1:2.5. The algorithm was tested with the AHA and MIT-BIH databases. A sensitivity of 99.04% and a specificity of 99.62% were obtained in detection of 542014 beats. The algorithm copes successfully with different complicated cases of single channel ventricular beat detection. It is aimed to simulate to some extent the experience of the cardiologist, rather than to rely on mathematical approaches adopted from the theory of signal analysis. The algorithm is open to improvement, especially in the part concerning the discrimination between normal QRS complexes and ectopic beats.

  3. Evaluation of the CT dose index for scans with an ECG using a 320-row multiple-detector CT scanner

    International Nuclear Information System (INIS)

    Kobayashi, Masanao; Asada, Yasuki; Matsubara, Kosuke; Koshida, Kichiro; Suzuki, Shouichi; Matsunaga, Yuta; Kawaguchi, Ai; Haba, Tomonobu; Katada, Kazuhiro; Toyama, Hiroshi

    2015-01-01

    The relationship between heart rate (HR) and computed tomography dose index (CTDI) was evaluated using an electrocardiogram (ECG) gate scan for scan applications such as prospective triggering, Ca scoring, target computed tomography angiography (CTA), prospective CTA and retrospective gating, continuous CTA/CFA (cardiac functional analysis) and CTA/CFA modulation. Even in the case of a volume scan, doses for the multiple scan average dose were similar to those for CTDI. Moreover, it was found that the ECG gate scan yields significantly different doses. When selecting the optimum scan, the doses were dependent on many factors such as HR, scan rotation time, active time, pre-specified cardiac phase and modulation rate. Therefore, it is necessary to take these results into consideration when selecting the scanning parameters. (authors)

  4. Spatiotemporal Characteristics of QRS Complexes Enable the Diagnosis of Brugada Syndrome Regardless of the Appearance of a Type 1 ECG.

    Science.gov (United States)

    Guillem, Maria S; Climent, Andreu M; Millet, José; Berne, Paola; Ramos, Rafael; Brugada, Josep; Brugada, Ramon

    2016-05-01

    The diagnosis of Brugada syndrome based on the ECG is hampered by the dynamic nature of its ECG manifestations. Brugada syndrome patients are only 25% likely to present a type 1 ECG. The objective of this study is to provide an ECG diagnostic criterion for Brugada syndrome patients that can be applied consistently even in the absence of a type 1 ECG. We recorded 67-lead body surface potential maps from 94 Brugada syndrome patients and 82 controls (including right bundle branch block patients and healthy individuals). The spatial propagation direction during the last r' wave and the slope at the end of the QRS complex were measured and compared between patients groups. Receiver-operating characteristic curves were constructed for half of the database to identify optimal cutoff values; sensitivity and specificity for these cutoff values were measured in the other half of the database. A spontaneous type 1 ECG was present in only 30% of BrS patients. An orientation in the sagittal plane syndrome with a sensitivity of 69% and a specificity of 97% in non-type 1 Brugada syndrome patients. Spatiotemporal characteristics of surface ECG recordings can enable a robust identification of BrS even without the presence of a type 1 ECG. © 2016 Wiley Periodicals, Inc.

  5. [Syncope: electrocardiogram and autonomic function tests].

    Science.gov (United States)

    Uribe, William; Baranchuk, Adrián; Botero, Federico

    2016-12-23

    Syncope represents one of the most frequent reasons for consultation in the emergency department. A proper identification will allow a precise etiologic approach and the optimization of delivery of health resources.
Once knowing the classification of syncope; it is the clinical interrogatory what enables to discriminate which of these patients present with a neurogenic mediated syncope or a cardiac mediated syncope. The use of diagnostic methods such as the tilt test, will clarify what type of neurally mediated syncope predominates in the patient.
The electrocardiogram is the cornerstone in the identification of those patients who had a true episode of self-limited or aborted sudden death as the first manifestation of their syncope, a fact which provides prognostic and therapeutic information that will impact the morbidity and mortality.

  6. Electrocardiogram Signal Quality Assessment Based on Structural Image Similarity Metric.

    Science.gov (United States)

    Shahriari, Yalda; Fidler, Richard; Pelter, Michele M; Bai, Yong; Villaroman, Andrea; Hu, Xiao

    2018-04-01

    We developed an image-based electrocardiographic (ECG) quality assessment technique that mimics how clinicians annotate ECG signal quality. We adopted the structural similarity measure (SSIM) to compare images of two ECG records that are obtained from displaying ECGs in a standard scale. Then, a subset of representative ECG images from the training set was selected as templates through a clustering method. SSIM between each image and all the templates were used as the feature vector for the linear discriminant analysis classifier. We also employed three commonly used ECG signal quality index (SQI) measures: baseSQI, kSQI, and sSQI to compare with the proposed image quality index (IQI) approach. We used 1926 annotated ECGs, recorded from patient monitors, and associated with six different ECG arrhythmia alarm types which were obtained previously from an ECG alarm study at the University of California, San Francisco (UCSF). In addition, we applied the templates from the UCSF database to test the SSIM approach on the publicly available PhysioNet Challenge 2011 data. For the UCSF database, the proposed IQI algorithm achieved an accuracy of 93.1% and outperformed all the SQI metrics, baseSQI, kSQI, and sSQI, with accuracies of 85.7%, 63.7%, and 73.8% respectively. Moreover, evaluation of our algorithm on the PhysioNet data showed an accuracy of 82.5%. The proposed algorithm showed better performance for assessing ECG signal quality than traditional signal processing methods. A more accurate assessment of ECG signal quality can lead to a more robust ECG-based diagnosis of cardiovascular conditions.

  7. Meet the challenge of high-pass filter and ST-segment requirements with a DC-coupled digital electrocardiogram amplifier.

    Science.gov (United States)

    Abächerli, Roger; Schmid, Hans-Jakob

    2009-01-01

    The high-pass filter (HPF) in an electrocardiogram (ECG) amplifier can distort the ST segment required for ischemia interpretation. Therefore, the current standards and guidelines require -3 dB for monitoring and -0.9 dB for diagnostic purposes at 0.67 Hz. In addition, a minimal reaction to a rectangular pulse of 300 microV has to be proven. We raise the question of why the design of a DC-coupled digital ECG amplifier is reasonable when today the AC-coupled digital ECG amplifier including a 0.05-Hz HPF works so well, meets all required standards, and is already safe. We make the hypothesis that a digital DC-coupled ECG amplifier can as well meet the requirements and guarantee the same safety levels at the same time provide a higher degree of freedom for future improvements of the ECG signal quality. Firstly, a historical research of the origin of the 0.05-Hz requirement has been made. Secondly, triangular pulses simulating unipolar QRS complexes have been passed through a digital filter to get qualitative results of the HPF response. And finally, to quantitatively describe the filter response, corresponding test requirement signals have been passed through a digital filter to simulate the HPF behavior, therefore understanding the reasons for the required tests. The oldest reference found to the 0.05-Hz filter dates from 1937. At that time, DC-coupled analogue ECG amplifiers were used. The simulation of the AC-coupled ECG amplifier with a first-order analogue HPF shows that the rectangular 300-microV pulse is a phase requirement and more restrictive than the frequency requirements. The phase requirement in fact corresponds to the requirement of a 0.05-Hz first-order analogue HPF (-3 dB) even if -0.9 dB at 0.67 Hz is required. The DC-coupled ECG amplifier (without an analogue HPF and during online and off-line acquisition) fulfils the phase and frequency requirements, just as the digital AC-coupled ECG amplifier does. An AC-coupled ECG amplifier based on a first

  8. Human Identification by Cross-Correlation and Pattern Matching of Personalized Heartbeat: Influence of ECG Leads and Reference Database Size.

    Science.gov (United States)

    Jekova, Irena; Krasteva, Vessela; Schmid, Ramun

    2018-01-27

    Human identification (ID) is a biometric task, comparing single input sample to many stored templates to identify an individual in a reference database. This paper aims to present the perspectives of personalized heartbeat pattern for reliable ECG-based identification. The investigations are using a database with 460 pairs of 12-lead resting electrocardiograms (ECG) with 10-s durations recorded at time-instants T1 and T2 > T1 + 1 year. Intra-subject long-term ECG stability and inter-subject variability of personalized PQRST (500 ms) and QRS (100 ms) patterns is quantified via cross-correlation, amplitude ratio and pattern matching between T1 and T2 using 7 features × 12-leads. Single and multi-lead ID models are trained on the first 230 ECG pairs. Their validation on 10, 20, ... 230 reference subjects (RS) from the remaining 230 ECG pairs shows: (i) two best single-lead ID models using lead II for a small population RS = (10-140) with identification accuracy AccID = (89.4-67.2)% and aVF for a large population RS = (140-230) with AccID = (67.2-63.9)%; (ii) better performance of the 6-lead limb vs. the 6-lead chest ID model-(91.4-76.1)% vs. (90.9-70)% for RS = (10-230); (iii) best performance of the 12-lead ID model-(98.4-87.4)% for RS = (10-230). The tolerable reference database size, keeping AccID > 80%, is RS = 30 in the single-lead ID scenario (II); RS = 50 (6 chest leads); RS = 100 (6 limb leads), RS > 230-maximal population in this study (12-lead ECG).

  9. Adaptive removal of gradients-induced artefacts on ECG in MRI: a performance analysis of RLS filtering.

    Science.gov (United States)

    Sansone, Mario; Mirarchi, Luciano; Bracale, Marcello

    2010-05-01

    One of the main vital signs used in patient monitoring during Magnetic Resonance Imaging (MRI) is Electro-Cardio-Gram (ECG). Unfortunately, magnetic fields gradients induce artefacts which severely affect ECG quality. Adaptive Noise Cancelling (ANC) is one of the preferred techniques for artefact removal. ANC involves the adaptive estimation of the impulse response of the system constituted by the MRI equipment, the patient and the ECG recording device. Least Mean Square (LMS) adaptive filtering has been traditionally employed because of its simplicity: anyway, it requires the choice of a step-size parameter, whose proper value for the specific application must be estimated case by case: an improper choice could yield slow convergence and unsatisfactory behaviour. Recursive Least Square (RLS) algorithm has, potentially, faster convergence while not requiring any parameter. As far as the authors' knowledge, there is no systematic analysis of performances of RLS in this scenario. In this study we evaluated the performance of RLS for adaptive removal of artefacts induced by magnetic field gradients on ECG in MRI, in terms of efficacy of suppression. Tests have been made on real signals, acquired via an expressly developed system. A comparison with LMS was made on the basis of opportune performance indices. Results indicate that RLS is superior to LMS in several respects.

  10. Impact of diagnostic ECG to wire delay in STEMI patients treated with primary PCI - a DANAMI-3 substudy

    DEFF Research Database (Denmark)

    Nepper-Christensen, Lars; Lønborg, Jacob; Høfsten, Dan Eik

    2018-01-01

    AIMS: We evaluated the impact of delay from diagnostic pre-hospital electrocardiogram (ECG) to wiring of the infarct related vessel (ECG-to-wire) >120 minutes on cardiovascular magnetic resonance (CMR) markers of reperfusion success and clinical outcome in patients with ST-segment elevation...... myocardial infarction (STEMI). METHODS AND RESULTS: We included 1492 patients in the analyses of clinical outcome. CMR was performed in 748 patients to evaluate infarct size and myocardial salvage. In total, 304 patients (20%) had ECG-to-wire >120 minutes, which was associated with larger acute infarct size...... (18% [interquartile range (IQR), 10-28] vs. 15% [8-24]; p=0.022) and smaller myocardial salvage (0.42 [IQR 0.28-0.57] vs. 0.50 [IQR 0.34-0.70]; p=0.002). However, 33% of the patients with ECG-to-wire >120 minutes still had a substantial myocardial salvage of more than 0.50. In a multivariable analysis...

  11. Value of Exercise ECG for Risk Stratification in Suspected or Known CAD in the Era of Advanced Imaging Technologies.

    Science.gov (United States)

    Bourque, Jamieson M; Beller, George A

    2015-11-01

    Exercise stress electrocardiography (ExECG) is underutilized as the initial test modality in patients with interpretable electrocardiograms who are able to exercise. Although stress myocardial imaging techniques provide valuable diagnostic and prognostic information, variables derived from ExECG can yield substantial data for risk stratification, either supplementary to imaging variables or without concurrent imaging. In addition to exercise-induced ischemic ST-segment depression, such markers as ST-segment elevation in lead aVR, abnormal heart rate recovery post-exercise, failure to achieve target heart rate, and poor exercise capacity improve risk stratification of ExECG. For example, patients achieving ≥10 metabolic equivalents on ExECG have a very low prevalence of inducible ischemia and an excellent prognosis. In contrast, cardiac imaging techniques add diagnostic and prognostic value in higher-risk populations (e.g., poor functional capacity, diabetes, or chronic kidney disease). Optimal test selection for symptomatic patients with suspected coronary artery disease requires a patient-centered approach factoring in the risk/benefit ratio and cost-effectiveness. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  12. ECG acquisition and automated remote processing

    CERN Document Server

    Gupta, Rajarshi; Bera, Jitendranath

    2014-01-01

    The book is focused on the area of remote processing of ECG in the context of telecardiology, an emerging area in the field of Biomedical Engineering Application. Considering the poor infrastructure and inadequate numbers of physicians in rural healthcare clinics in India and other developing nations, telemedicine services assume special importance. Telecardiology, a specialized area of telemedicine, is taken up in this book considering the importance of cardiac diseases, which is prevalent in the population under discussion. The main focus of this book is to discuss different aspects of ECG acquisition, its remote transmission and computerized ECG signal analysis for feature extraction. It also discusses ECG compression and application of standalone embedded systems, to develop a cost effective solution of a telecardiology system.

  13. Specificity of elevated intercostal space ECG recording for the type 1 Brugada ECG pattern

    DEFF Research Database (Denmark)

    Holst, Anders G; Tangø, Mogens; Batchvarov, Velislav

    2012-01-01

    Right precordial (V1-3) elevated electrode placement ECG (EEP-ECG) is often used in the diagnosis of Brugada syndrome (BrS). However, the specificity of this has only been studied in smaller studies in Asian populations. We aimed to study this in a larger European population.......Right precordial (V1-3) elevated electrode placement ECG (EEP-ECG) is often used in the diagnosis of Brugada syndrome (BrS). However, the specificity of this has only been studied in smaller studies in Asian populations. We aimed to study this in a larger European population....

  14. Electrocardiogram-derived respiration in screening of sleep-disordered breathing.

    Science.gov (United States)

    Babaeizadeh, Saeed; Zhou, Sophia H; Pittman, Stephen D; White, David P

    2011-01-01

    Methods for assessment of sleep-disordered breathing (SDB), including sleep apnea, range from a simple questionnaire to complex multichannel polysomnography. Inexpensive and efficient electrocardiogram (ECG)-based solutions could potentially fill the gap and provide a new SDB screening tool. In addition to the heart rate variability (HRV)-based SDB screening method that we reported a year ago, we have developed a novel method based on ECG-derived respiration (EDR). This method derives the respiratory waveform by (a) measuring peak-to-trough QRS amplitude in a single-channel ECG, (b) removing outlier introduced by noise and artifacts, (c) interpolating the derived values, and (d) filtering values within the respiration rates of 5 and 25 cycles per minute. Each 30 seconds of the respiratory waveform is then classified as normal, SDB, or indeterminate epoch. The previously reported HRV-based method, applied at the same time, is based on power spectrum of heart rate over a sliding 6-minute time window to classify the middle 30-second epoch. We then combined the EDR- and HRV-based techniques to optimize the classification of each epoch. The combined method further improved the accuracy of SDB screening in an independent test database with annotated SDB epochs. The development database was from PhysioNet (n = 25 polysomnograms). The test database was from Sleep Health Centers in Boston (n = 1907 polysomnogram) where the SDB epochs (n = 1,538,222 epochs) were scored using American Academy of Sleep Medicine criteria. The first test was to classify every epoch in the evaluation data set. The combined EDR and HRV method classified 78% of the epochs as either normal or SDB and 22% as indeterminate, with a total accuracy of 88% for scored epochs (not indeterminate). The second test was to evaluate the SDB status for each patient. The algorithm correctly classified 71% of patients with either moderate-to-severe SDB or mild-to-no SDB. We believe that the ECG-based methods

  15. Smartphone home monitoring of ECG

    Science.gov (United States)

    Szu, Harold; Hsu, Charles; Moon, Gyu; Landa, Joseph; Nakajima, Hiroshi; Hata, Yutaka

    2012-06-01

    A system of ambulatory, halter, electrocardiography (ECG) monitoring system has already been commercially available for recording and transmitting heartbeats data by the Internet. However, it enjoys the confidence with a reservation and thus a limited market penetration, our system was targeting at aging global villagers having an increasingly biomedical wellness (BMW) homecare needs, not hospital related BMI (biomedical illness). It was designed within SWaP-C (Size, Weight, and Power, Cost) using 3 innovative modules: (i) Smart Electrode (lowpower mixed signal embedded with modern compressive sensing and nanotechnology to improve the electrodes' contact impedance); (ii) Learnable Database (in terms of adaptive wavelets transform QRST feature extraction, Sequential Query Relational database allowing home care monitoring retrievable Aided Target Recognition); (iii) Smartphone (touch screen interface, powerful computation capability, caretaker reporting with GPI, ID, and patient panic button for programmable emergence procedure). It can provide a supplementary home screening system for the post or the pre-diagnosis care at home with a build-in database searchable with the time, the place, and the degree of urgency happened, using in-situ screening.

  16. Coronary Artery Stent Evaluation Using a Vascular Model at 64-Detector Row CT: Comparison between Prospective and Retrospective ECG-Gated Axial Scans

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Shigeru; Furui, Shigeru; Kaminaga, Tatsuro; Miyazawa, Akiyoshi; Ueno, Yasunari; Konno, Kumiko [Teikyo University School of Medicine, Tokyo (Japan); Kuwahara, Sadatoshi; Mehta, Dhruv [Philips Electronics Japan, Ltd. Medical Systems, Tokyo (Japan)

    2009-06-15

    We wanted to evaluate the performance of prospective electrocardiogram (ECG)-gated axial scans for assessing coronary stents as compared with retrospective ECG-gated helical scans. As for a vascular model of the coronary artery, a tube of approximately 2.5-mm inner diameter was adopted and as for stents, three (Bx-Velocity, Express2, and Micro Driver) different kinds of stents were inserted into the tube. Both patent and stenotic models of coronary artery were made by instillating different attenuation (396 vs. 79 Hounsfield unit [HU]) of contrast medium within the tube in tube model. The models were scanned with two types of scan methods with a simulated ECG of 60 beats per minute and using display field of views (FOVs) of 9 and 18 cm. We evaluated the in-stent stenosis visually, and we measured the attenuation values and the diameter of the patent stent lumen. The visualization of the stent lumen of the vascular models was improved with using the prospective ECG-gated axial scans and a 9-cm FOV. The inner diameters of the vascular models were underestimated with mean measurement errors of -1.10 to -1.36 mm. The measurement errors were smaller with using the prospective ECG-gated axial scans (Bx-Velocity and Express2, p < 0.0001; Micro Driver, p = 0.0004) and a 9-cm FOV (all stents: p < 0.0001), as compared with the other conditions, respectively. The luminal attenuation value was overestimated in each condition. For the luminal attenuation measurement, the use of prospective ECG-gated axial scans provided less measurement error compared with the retrospective ECG-gated helical scans (all stents: p < 0.0001), and the use of a 9-cm FOV tended to decrease the measurement error. The visualization of coronary stents is improved by the use of prospective ECG-gated axial scans and using a small FOV with reduced blooming artifacts and increased spatial resolution.

  17. Time interval between maternal electrocardiogram and venous Doppler waves in normal pregnancy and preeclampsia: a pilot study.

    Science.gov (United States)

    Tomsin, K; Mesens, T; Molenberghs, G; Peeters, L; Gyselaers, W

    2012-12-01

    To evaluate the time interval between maternal electrocardiogram (ECG) and venous Doppler waves at different stages of uncomplicated pregnancy (UP) and in preeclampsia (PE). Cross-sectional pilot study in 40 uncomplicated singleton pregnancies, categorized in four groups of ten according to gestational age: 10 - 14 weeks (UP1), 18 - 23 weeks (UP2), 28 - 33 weeks (UP3) and ≥ 37 weeks (UP4) of gestation. A fifth group of ten women with PE was also included. A Doppler flow examination at the level of renal interlobar veins (RIV) and hepatic veins (HV) was performed according to a standard protocol, in association with a maternal ECG. The time interval between the ECG P-wave and the corresponding A-deflection of the venous Doppler waves was measured (PA), and expressed relative to the duration of the cardiac cycle (RR), and labeled PA/RR. In hepatic veins, the PA/RR is longer in UP 4 than in UP 1 (0.48 ± 0.15 versus 0.29 ± 0.09, p ≤ 0.001). When all UP groups were compared, the PA/RR increased gradually with gestational age. In PE, the HV PA/RR is shorter than in UP 3 (0.25 ± 0.09 versus 0.42 ± 0.14, p advanced gestational stages are consistent with known features of maternal cardiovascular adaptation. Shorter values in preeclampsia are consistent with maternal cardiovascular maladaptation mechanisms. Our pilot study invites more research of the relevance of the time interval between maternal ECG and venous Doppler waves as a new parameter for studying the gestational cardiovascular (patho)physiology of the maternal venous compartment by duplex sonography. © Georg Thieme Verlag KG Stuttgart · New York.

  18. Modest agreement in ECG interpretation limits the application of ECG screening in young athletes.

    Science.gov (United States)

    Brosnan, Maria; La Gerche, Andre; Kumar, Saurabh; Lo, Wilson; Kalman, Jonathan; Prior, David

    2015-01-01

    Athlete ECG screening has been recommended by several international sporting bodies; however, a number of controversies remain regarding the accuracy of ECG screening. An important component that has not been assessed is the reproducibility of ECG interpretation. The purpose of this study was to assess the variability of ECG interpretation among experienced physicians when screening a large number of athletes. A sports cardiologist, a sports medicine physician, and an electrophysiologist analyzed 440 consecutive screening ECGs from asymptomatic athletes and were asked to classify the ECGs according to the 2010 European Society of Cardiology criteria as normal (or demonstrating training related ECG changes) or abnormal. When an abnormal ECG was identified, they were asked to outline what follow-up investigations they would recommend. The reported prevalence of abnormal ECGs ranged from 13.4% to 17.5%. Agreement on which ECGs were abnormal ranged from poor (κ = 0.297) to moderate (κ = 0.543) between observers. Suggested follow-up investigations were varied, and follow-up costs ranged from an additional A$30-A$129 per screening episode. Neither of the 2 subjects (0.45%) in the cohort with significant pathology diagnosed as a result of screening were identified correctly by all 3 physicians. Even when experienced physicians interpret athletes' ECGs according to current standards, there is significant interobserver variability that results in false-positive and false-negative results, thus reducing the effectiveness and increasing the social and economic cost of screening. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  19. Extraction of the fetal ECG in noninvasive recordings by signal decompositions

    International Nuclear Information System (INIS)

    Christov, I; Simova, I; Abächerli, R

    2014-01-01

    No signal processing technique has been able to reliably deliver an undistorted fetal electrocardiographic (fECG) signal from electrodes placed on the maternal abdomen because of the low signal-to-noise ratio of the fECG recorded from the maternal body surface. As a result, this led to increased rates of Caesarean deliveries of healthy infants. In an attempt to solve the problem, Physionet/Computing in Cardiology announced the 2013 Challenge: noninvasive fetal ECG. We are suggesting a method for cancellation of the maternal ECG consisting of: maternal QRS detection, heart rate dependant P-QRS-T interval selection, location of the fiducial points inside this interval for best matching by cross correlation, superimposition of the intervals, calculation of the mean signal of the P-QRS-T interval, and sequential subtraction of the mean signal from the whole fECG recording. Three signal decomposition methods were further applied in order to enhance the fetal QRSs (fQRS): principal component analysis, root-mean-square and Hotelling’s T-squared. A combined lead of all decompositions was synthesized and fQRS detection was performed on it. The current research differs from the Challenge in that it uses three signal decomposition methods to enhance the fECG. The new results for 97 recordings of test set B are: 305.657 for Event 4: Fetal heart rate (FHR) and 23.062 for Event 5: Fetal RR interval (FRR). (paper)

  20. Non-invasive prediction of catheter ablation outcome in persistent atrial fibrillation by fibrillatory wave amplitude computation in multiple electrocardiogram leads.

    Science.gov (United States)

    Zarzoso, Vicente; Latcu, Decebal G; Hidalgo-Muñoz, Antonio R; Meo, Marianna; Meste, Olivier; Popescu, Irina; Saoudi, Nadir

    2016-12-01

    Catheter ablation (CA) of persistent atrial fibrillation (AF) is challenging, and reported results are capable of improvement. A better patient selection for the procedure could enhance its success rate while avoiding the risks associated with ablation, especially for patients with low odds of favorable outcome. CA outcome can be predicted non-invasively by atrial fibrillatory wave (f-wave) amplitude, but previous works focused mostly on manual measures in single electrocardiogram (ECG) leads only. To assess the long-term prediction ability of f-wave amplitude when computed in multiple ECG leads. Sixty-two patients with persistent AF (52 men; mean age 61.5±10.4years) referred for CA were enrolled. A standard 1-minute 12-lead ECG was acquired before the ablation procedure for each patient. F-wave amplitudes in different ECG leads were computed by a non-invasive signal processing algorithm, and combined into a mutivariate prediction model based on logistic regression. During an average follow-up of 13.9±8.3months, 47 patients had no AF recurrence after ablation. A lead selection approach relying on the Wald index pointed to I, V1, V2 and V5 as the most relevant ECG leads to predict jointly CA outcome using f-wave amplitudes, reaching an area under the curve of 0.854, and improving on single-lead amplitude-based predictors. Analysing the f-wave amplitude in several ECG leads simultaneously can significantly improve CA long-term outcome prediction in persistent AF compared with predictors based on single-lead measures. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  1. The role of computerized diagnostic proposals in the interpretation of the 12-lead electrocardiogram by cardiology and non-cardiology fellows.

    Science.gov (United States)

    Novotny, Tomas; Bond, Raymond; Andrsova, Irena; Koc, Lumir; Sisakova, Martina; Finlay, Dewar; Guldenring, Daniel; Spinar, Jindrich; Malik, Marek

    2017-05-01

    Most contemporary 12-lead electrocardiogram (ECG) devices offer computerized diagnostic proposals. The reliability of these automated diagnoses is limited. It has been suggested that incorrect computer advice can influence physician decision-making. This study analyzed the role of diagnostic proposals in the decision process by a group of fellows of cardiology and other internal medicine subspecialties. A set of 100 clinical 12-lead ECG tracings was selected covering both normal cases and common abnormalities. A team of 15 junior Cardiology Fellows and 15 Non-Cardiology Fellows interpreted the ECGs in 3 phases: without any diagnostic proposal, with a single diagnostic proposal (half of them intentionally incorrect), and with four diagnostic proposals (only one of them being correct) for each ECG. Self-rated confidence of each interpretation was collected. Availability of diagnostic proposals significantly increased the diagnostic accuracy (p<0.001). Nevertheless, in case of a single proposal (either correct or incorrect) the increase of accuracy was present in interpretations with correct diagnostic proposals, while the accuracy was substantially reduced with incorrect proposals. Confidence levels poorly correlated with interpretation scores (rho≈2, p<0.001). Logistic regression showed that an interpreter is most likely to be correct when the ECG offers a correct diagnostic proposal (OR=10.87) or multiple proposals (OR=4.43). Diagnostic proposals affect the diagnostic accuracy of ECG interpretations. The accuracy is significantly influenced especially when a single diagnostic proposal (either correct or incorrect) is provided. The study suggests that the presentation of multiple computerized diagnoses is likely to improve the diagnostic accuracy of interpreters. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Superior success rate of intracavitary electrocardiogram guidance for peripherally inserted central catheter placement in patients with cancer: A randomized open-label controlled multicenter study.

    Directory of Open Access Journals (Sweden)

    Ling Yuan

    Full Text Available Intracavitary electrocardiogram (IC ECG guidance emerges as a new technique for peripherally inserted central catheters (PICCs placement and demonstrates many potential advantages in recent observational studies.To determine whether IC ECG-guided PICCs provide more accurate positioning of catheter tips compared to conventional anatomical landmarks in patients with cancer undergoing chemotherapy.In this multicenter, open-label, randomized controlled study (ClinicalTrials.gov number, NCT02409589, a total of 1,007 adult patients were assigned to receive either IC ECG guidance (n = 500 or anatomical landmark guidance (n = 507 for PICC positioning. The confirmative catheter tip positioning x-ray data were centrally interpreted by independent radiologists. All reported analyses in the overall population were performed on an intention-to-treat basis. Analyses of pre-specified subgroups and a selected large subpopulation were conducted to explore consistency and accuracy.In the IC ECG-guided group, the first-attempt success rate was 89.2% (95% confidence interval [CI], 86.5% to 91.9%, which was significantly higher than 77.4% (95% CI, 73.7% to 81.0% in the anatomical landmark group (P < 0.0001. This trend of superiority of IC ECG guidance was consistently noted in almost all prespecified patient subgroups and two selected large subpopulations, even when using optimal target rates for measurement. In contrast, the superiority nearly disappeared when PICCs were used via the left instead of right arms (interaction P-value = 0.021. No catheter-related adverse events were reported during the PICC intra-procedures in either group.Our findings indicated that the IC ECG-guided method had a more favorable positioning accuracy versus traditional anatomical landmarks for PICC placement in adult patients with cancer undergoing chemotherapy. Furthermore, there were no significant safety concerns reported for catheterization using the two techniques.

  3. Manifold learning based ECG-free free-breathing cardiac CINE MRI.

    Science.gov (United States)

    Usman, Muhammad; Atkinson, David; Kolbitsch, Christoph; Schaeffter, Tobias; Prieto, Claudia

    2015-06-01

    To present and validate a manifold learning (ML)-based method that can estimate both cardiac and respiratory navigator signals from electrocardiogram (ECG)-free free-breathing cardiac magnetic resonance imaging (MRI) data to achieve self-gated retrospective CINE reconstruction. In this work the use of the ML method is demonstrated for 2D cardiac CINE to achieve both cardiac and respiratory self-gating without the need of an external navigator or ECG signal. This is achieved by sequentially applying ML to two sets of retrospectively reconstructed real-time images with differing temporal resolutions. A 1D cardiac signal is estimated by applying ML to high temporal resolution real-time images reconstructed from the acquired data. Using the estimated cardiac signal, a 1D respiratory signal was obtained by applying the ML method to low temporal resolution images reconstructed from the same acquired data for each cardiac cycle. Data were acquired in five volunteers with a 2D golden angle radial trajectory in a balanced steady-state free precession (b-SSFP) acquisition. The accuracy of the estimated cardiac signal was calculated as the standard deviation of the temporal difference between the estimated signal and the recorded ECG. The correlation between the estimated respiratory signal and standard pencil beam navigator signal was evaluated. Gated CINE reconstructions (20 cardiac phases per cycle, temporal resolution ∼30 msec) using the estimated cardiac and respiratory signals were qualitatively compared against conventional ECG-gated breath-hold CINE acquisitions. Accurate cardiac signals were estimated with the proposed method, with an error standard deviation in comparison to ECG lower than 20 msec. Respiratory signals estimated with the proposed method achieved a mean cross-correlation of 94% with respect to standard pencil beam navigator signals. Good quality visual scores of 2.80 ± 0.45 (scores from 0, bad, to 4, excellent quality) were observed for the

  4. High Resolution ECG for Evaluation of Heart Function During Exposure to Subacute Hypobaric Hypoxia

    Science.gov (United States)

    Zupet, Petra; Finderle, Zarko; Schlegel, Todd T.; Princi, Tanja; Starc, Vito

    2010-01-01

    High altitude climbing presents a wide spectrum of health risks, including exposure to hypobaric hypoxia. Risks are also typically exacerbated by the difficulty in appropriately monitoring for early signs of organ dysfunction in remote areas. We investigated whether high resolution advanced ECG analysis might be helpful as a non-invasive and easy-to-use tool (e.g., instead of Doppler echocardiography) for evaluating early signs of heart overload in hypobaric hypoxia. Nine non-acclimatized healthy trained alpine rescuers (age 43.7 plus or minus 7.3 years) climbed in four days to the altitude of 4,200 m on Mount Ararat. Five-minute high-resolution 12-lead electrocardiograms (ECGs) were recorded (Cardiosoft) in each subject at rest in the supine position on different days but at the same time of day at four different altitudes: 400 m (reference altitude), 1,700 m, 3,200 m and 4,200 m. Changes in conventional and advanced resting ECG parameters, including in beat-to-beat QT and RR variability, waveform complexity, signal-averaged, high-frequency and spatial/spatiotemporal ECG was estimated by calculation of the regression coefficients in independent linear regression models. A p-value of less than 0.05 was adopted as statistically significant. As expected, the RR interval and its variability both decreased with increasing altitude, with trends k = -96 ms/1000 m with p = 0.000 and k = -9 ms/1000 m with p = 0.001, respectively. Significant changes were found in P-wave amplitude, which nearly doubled from the lowest to the highest altitude (k = 41.6 microvolt/1000 m with p = 0.000), and nearly significant changes in P-wave duration (k = 2.9 ms/1000 m with p = 0.059). Changes were less significant or non-significant in other studied parameters including those of waveform complexity, signal-averaged, high-frequency and spatial/spatiotemporal ECG. High resolution ECG analysis, particularly of the P wave, shows promise as a tool for monitoring early changes in heart function

  5. Acute myocardial infarction due to spontaneous, localized, acute dissection of the sinus of Valsalva detected by intravascular ultrasound and electrocardiogram-gated computed tomography.

    Science.gov (United States)

    Ichihashi, Taku; Ito, Tsuyoshi; Murai, Shunsuke; Ikehara, Noriyuki; Fujita, Hiroshi; Suda, Hisao; Ohte, Nobuyuki

    2016-09-01

    A 58-year-old man was referred to our hospital because of chest pain. The 12-lead electrocardiogram (ECG) revealed ST-segment elevation in II, III, and a Vf with advanced heart block. Transthoracic echocardiography demonstrated aortic root dilatation at the sinus of Valsalva, moderate aortic regurgitation, and decreased wall motion in the inferior part of the left ventricle. Non-ECG-gated enhanced computed tomography (CT) did not reveal an aortic dissection. The patient underwent emergent coronary angiography, which revealed a severely narrowed ostium of the right coronary artery (RCA). Percutaneous coronary intervention (PCI) was performed under intravascular ultrasound (IVUS) guidance. IVUS images demonstrated an intimal flap extending from the aortic wall to the proximal RCA, suggesting that a periaortic hematoma in the false lumen compressed the ostium of the RCA, leading to acute myocardial infarction. To recover hemodynamic stability, the RCA ostium was stented. Subsequent ECG-gated enhanced CT clearly depicted the entry point and extension of the dissection localized within the sinus of Valsalva. The dissection likely involved the left main coronary artery and an emergent Bentall procedure was performed. Intraoperative findings confirmed an intimal tear and extension of the dissection. Thus, ECG-gated CT can clearly depict the entry site and extension of a dissection occurring in the localized area that cannot be detected by conventional CT.

  6. Impact of electrocardiogram screening during drug challenge test for the prediction of T-wave oversensing by a subcutaneous implantable cardioverter defibrillator in patients with Brugada syndrome.

    Science.gov (United States)

    Kamakura, Tsukasa; Wada, Mitsuru; Ishibashi, Kohei; Inoue, Yuko Y; Miyamoto, Koji; Okamura, Hideo; Nagase, Satoshi; Noda, Takashi; Aiba, Takeshi; Yasuda, Satoshi; Kusano, Kengo

    2017-10-01

    Screening tests conducted at rest may be inadequate for the prediction of the T-wave oversensing (TWOS) in subcutaneous implantable cardioverter defibrillator (S-ICD) candidates with Brugada syndrome (BrS) because of the dynamic nature of electrocardiogram (ECG) morphology. We evaluated the utility of ECG screening during drug challenge (DC) for prediction of TWOS in BrS patients implanted with an S-ICD. The study enrolled 6 consecutive BrS patients implanted with an S-ICD. In addition to baseline ECG screening, pre-implant screening during DC using a sodium channel blocker was performed in all patients. All patients underwent appropriate morphological analysis on baseline ECG screening; however, 2 BrS patients (33%) showed inappropriate sensing during DC. During 243 days of follow-up after S-ICD implantation, no patient experienced an appropriate shock. TWOS was confirmed during exercise testing in one of 2 patients who showed inappropriate sensing during DC. However, one patient with appropriate sensing during DC experienced recurrent episodes of inappropriate shocks due to TWOS during exercise. The present initial experience indicates that further studies are needed to detect the risk for TWOS from an S-ICD in BrS patients.

  7. Estimation of lung volume and pressure from electrocardiogram

    KAUST Repository

    Elsayed, Gamal Eldin Fathy Amin

    2011-05-01

    The Electrocardiography (ECG) is a tool measuring the electrical excitation of the heart that is extensively used for diagnosis and monitoring of heart diseases. The ECG signal reflects not only the heart activity but also many other physiological processes. The respiratory activity is a prominent process that affects the ECG signal due to the close proximity of the heart and the lungs and, on the other hand, due to neural regulatory processes. In this paper, several means for the estimation of the respiratory process from the ECG signal are presented. The results show a strong correlation of the voltage difference between the R and S peak of the ECG and the lung\\'s volume and pressure. Correlation was also found for some features of the vector ECG, which is a two dimensional graph of two different ECG signals. The potential benefit of the multiparametric evaluation of the ECG signal is a reduction of the number of sensors connected to patients, which will increase the patients\\' comfort and reduce the costs associated with healthcare. In particular, it is relevant for sleep monitoring, where a reduction of the number of different sensors would facilitate a more natural sleeping environment and hence a higher sensitivity of the diagnosis. © 2011 IEEE.

  8. The electrocardiogram made (really) easy: Using small-group ...

    African Journals Online (AJOL)

    Medicine designed small-group tutorials using animations and analogies as methods to improve the ECG interpretation skills of students. Objectives. To improve students' ability to interpret ECGs and assess their perceptions of the tutorials. Methods. A questionnaire was administered to 67 final-year medical students after ...

  9. Measurement and monitoring of electrocardiogram belt tension in premature infants for assessment of respiratory function

    Directory of Open Access Journals (Sweden)

    Hegyi Thomas

    2007-04-01

    Full Text Available Abstract Background Monitoring of the electrocardiogram (ECG in premature infants with conventional adhesive-backed electrodes can harm their sensitive skin. Use of an electrode belt prevents skin irritation, but the effect of belt pressure on respiratory function is unknown. A strain gauge sensor is described which measures applied belt tension. Method The device frame was comprised of an aluminum housing and slide to minimize the device weight. Velcro tabs connected housing and slide to opposite tabs located at the electrode belt ends. The slide was connected to a leaf spring, to which were bonded two piezoresistive transducers in a half-bridge circuit configuration. The device was tested for linearity and calibrated. The effect on infant respiratory function of constant belt tension in the normal range (30 g–90 g was determined. Results The mechanical response to a step input was second order (fn = 401 Hz, ζ = 0.08. The relationship between applied tension and output voltage was linear in the range 25–225 gm of applied tension (r2 = 0.99. Measured device sensitivity was 2.18 mV/gm tension using a 5 V bridge excitation voltage. When belt tension was increased in the normal range from 30 gm to 90 gm, there was no significant change in heart rate and most respiratory functions during monitoring. At an intermediate level of tension of 50 gm, pulmonary resistance and work of breathing significantly decreased. Conclusion The mechanical and electrical design of a device for monitoring electrocardiogram electrode belt tension is described. Within the typical range of application tension, cardiovascular and respiratory function are not substantially negatively affected by electrode belt force.

  10. Embroidered Electrode with Silver/Titanium Coating for Long-Term ECG Monitoring

    Science.gov (United States)

    Weder, Markus; Hegemann, Dirk; Amberg, Martin; Hess, Markus; Boesel, Luciano F.; Abächerli, Roger; Meyer, Veronika R.; Rossi, René M.

    2015-01-01

    For the long-time monitoring of electrocardiograms, electrodes must be skin-friendly and non-irritating, but in addition they must deliver leads without artifacts even if the skin is dry and the body is moving. Today's adhesive conducting gel electrodes are not suitable for such applications. We have developed an embroidered textile electrode from polyethylene terephthalate yarn which is plasma-coated with silver for electrical conductivity and with an ultra-thin titanium layer on top for passivation. Two of these electrodes are embedded into a breast belt. They are moisturized with a very low amount of water vapor from an integrated reservoir. The combination of silver, titanium and water vapor results in an excellent electrode chemistry. With this belt the long-time monitoring of electrocardiography (ECG) is possible at rest as well as when the patient is moving. PMID:25599424

  11. Embroidered Electrode with Silver/Titanium Coating for Long-Term ECG Monitoring

    Directory of Open Access Journals (Sweden)

    Markus Weder

    2015-01-01

    Full Text Available For the long-time monitoring of electrocardiograms, electrodes must be skin-friendly and non-irritating, but in addition they must deliver leads without artifacts even if the skin is dry and the body is moving. Today’s adhesive conducting gel electrodes are not suitable for such applications. We have developed an embroidered textile electrode from polyethylene terephthalate yarn which is plasma-coated with silver for electrical conductivity and with an ultra-thin titanium layer on top for passivation. Two of these electrodes are embedded into a breast belt. They are moisturized with a very low amount of water vapor from an integrated reservoir. The combination of silver, titanium and water vapor results in an excellent electrode chemistry. With this belt the long-time monitoring of electrocardiography (ECG is possible at rest as well as when the patient is moving.

  12. Intelligent Medical Garments with Graphene-Functionalized Smart-Cloth ECG Sensors

    Science.gov (United States)

    Yapici, Murat Kaya; Alkhidir, Tamador Elboshra

    2017-01-01

    Biopotential signals are recorded mostly by using sticky, pre-gelled electrodes, which are not ideal for wearable, point-of-care monitoring where the usability of the personalized medical device depends critically on the level of comfort and wearability of the electrodes. We report a fully-wearable medical garment for mobile monitoring of cardiac biopotentials from the wrists or the neck with minimum restriction to regular clothing habits. The wearable prototype is based on elastic bands with graphene functionalized, textile electrodes and battery-powered, low-cost electronics for signal acquisition and wireless transmission. Comparison of the electrocardiogram (ECG) recordings obtained from the wearable prototype against conventional wet electrodes indicate excellent conformity and spectral coherence among the two signals. PMID:28420158

  13. A full custom analog front-end for long-time ECG monitoring.

    Science.gov (United States)

    Wen, Meiying; Cheng, Yayu; Li, Ye

    2013-01-01

    An analog front-end (AFE) used in portable electrocardiogram (ECG) monitoring devices is proposed. This AFE has included all necessary functions for the commercial applications. The core circuit consists of the instrumentation amplifier (IA), a 2(nd) order Butterworth low pass filter, and the second amplifying stage. The driven-right-leg circuit is integrated in the IA to effectively suppress the common mode interference. And the power management circuits provide a stable supply voltage, bias current and reference voltage for the other circuits. To guarantee the validity of the continuous monitoring data, the leadoff monitoring circuit is developed to monitor the connection of the leads. The chip is taped out with SMIC 0.18 µm CMOS process, and the measured results show that the common mode rejection ratio (CMRR) and power supply rejection ratio (PSRR) achieve 75 dB and 90dB respectively, and the equivalent input referred noise is 12 µV.

  14. IIR digital filter design for powerline noise cancellation of ECG signal using arduino platform

    Science.gov (United States)

    Rahmatillah, Akif; Ataulkarim

    2017-05-01

    Powerline noise has been one of significant noises of Electrocardiogram (ECG) signal measurement. This noise is characterized by a sinusoidal signal which has 50 Hz of noise and 0.3 mV of maximum amplitude. This paper describes the design of IIR Notch filter design to reject a 50 Hz power line noise. IIR filter coefficients were calculated using pole placement method with three variations of band stop cut off frequencies of (49-51)Hz, (48 - 52)Hz, and (47 - 53)Hz. The algorithm and coefficients of filter were embedded to Arduino DUE (ARM 32 bit microcontroller). IIR notch filter designed has been able to reject power line noise with average square of error value of 0.225 on (49-51) Hz filter design and 0.2831 on (48 - 52)Hz filter design.

  15. An ECG Index of P-Wave Force Predicts the Recurrence of Atrial Fibrillation after Pulmonary Vein Isolation.

    Science.gov (United States)

    Kanzaki, Yasunori; Inden, Yasuya; Ando, Monami; Kamikubo, Yosuke; Ito, Tadahiro; Mizutani, Yoshiaki; Kato, Hiroyuki; Fujii, Aya; Yanagisawa, Satoshi; Hirai, Makoto; Murohara, Toyoaki

    2016-11-01

    Although several prognostic factors of atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) have been investigated, the accurate prediction of AF recurrence remains difficult. We propose an electrocardiogram (ECG) index, the P-wave force (PWF), which is the product of the amplitude of the negative terminal phase of the P wave in the V1 electrode and the filtered P-wave duration, obtained by a signal-averaged P-wave analysis. This study was conducted to evaluate the impact of the PWF on the recurrence of AF after PVI. We retrospectively evaluated 79 paroxysmal AF patients (64 ± 9 years, 56 males) who underwent PVI by cryoballoon ablation. Standard 12-lead ECG and a P-wave signal-averaged electrocardiogram (SAECG) were recorded the day before and 1 month after the PVI procedure. During the mean follow-up of 10.2 months, AF recurred in 11 (14%) patients. The PWF 1 month after ablation was significantly higher in the recurrence group compared to that in the nonrecurrence group (8.8 ± 3.1 mVms vs 6.5 ± 2.9 mVms, P = 0.017). The patients with a PWF value ≥9.3 mVms had a s