WorldWideScience

Sample records for 15-minute clinical ecgs

  1. Comparison of linear–stochastic and nonlinear–deterministic algorithms in the analysis of 15-minute clinical ECGs to predict risk of arrhythmic death

    Directory of Open Access Journals (Sweden)

    James E Skinner

    2009-08-01

    Full Text Available James E Skinner1, Michael Meyer2, Brian A Nester3, Una Geary4, Pamela Taggart4, Antoinette Mangione4, George Ramalanjaona5, Carol Terregino6, William C Dalsey41Vicor Technologies, Inc., Boca Raton, FL, USA; 2Max Planck Institute for Experimental Physiology, Goettingen, Germany; 3Lehigh Valley Hospital, Allentown, PA, USA; 4Albert Einstein Medical Center, Philadelphia, PA, USA; 5North Shore University Hospital, Plainview, NY, USA; 6Cooper Medical Center, Camden, NJ, USAObjective: Comparative algorithmic evaluation of heartbeat series in low-to-high risk cardiac patients for the prospective prediction of risk of arrhythmic death (AD.Background: Heartbeat variation reflects cardiac autonomic function and risk of AD. Indices based on linear stochastic models are independent risk factors for AD in post-myocardial infarction (post-MI cohorts. Indices based on nonlinear deterministic models have superior predictability in retrospective data.Methods: Patients were enrolled (N = 397 in three emergency departments upon presenting with chest pain and were determined to be at low-to-high risk of acute MI (>7%. Brief ECGs were recorded (15 min and R-R intervals assessed by three nonlinear algorithms (PD2i, DFA, and ApEn and four conventional linear-stochastic measures (SDNN, MNN, 1/f-Slope, LF/HF. Out-of-hospital AD was determined by modified Hinkle–Thaler criteria.Results: All-cause mortality at one-year follow-up was 10.3%, with 7.7% adjudicated to be AD. The sensitivity and relative risk for predicting AD was highest at all time-points for the nonlinear PD2i algorithm (p ≤ 0.001. The sensitivity at 30 days was 100%, specificity 58%, and relative risk >100 (p ≤ 0.001; sensitivity at 360 days was 95%, specificity 58%, and relative risk >11.4 (p ≤ 0.001.Conclusions: Heartbeat analysis by the time-dependent nonlinear PD2i algorithm is comparatively the superior test.Keywords: autonomic nervous system, regulatory systems, electrophysiology, heart rate

  2. U.S. 15 Minute Precipitation Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. 15 Minute Precipitation Data is digital data set DSI-3260, archived at the National Climatic Data Center (NCDC). This is precipitation data. The primary source...

  3. Clinical disease presentation and ECG characteristics of LMNA mutation carriers

    Science.gov (United States)

    Ollila, Laura; Nikus, Kjell; Holmström, Miia; Jalanko, Mikko; Jurkko, Raija; Kaartinen, Maija; Koskenvuo, Juha; Kuusisto, Johanna; Kärkkäinen, Satu; Palojoki, Eeva; Reissell, Eeva; Piirilä, Päivi; Heliö, Tiina

    2017-01-01

    Objective Mutations in the LMNA gene encoding lamins A and C of the nuclear lamina are a frequent cause of cardiomyopathy accounting for 5–8% of familial dilated cardiomyopathy (DCM). Our aim was to study disease onset, presentation and progression among LMNA mutation carriers. Methods Clinical follow-up data from 27 LMNA mutation carriers and 78 patients with idiopathic DCM without an LMNA mutation were collected. In addition, ECG data were collected and analysed systematically from 20 healthy controls. Results Kaplan-Meier analysis revealed no difference in event-free survival (death, heart transplant, resuscitation and appropriate implantable cardioverter-defibrillator therapy included as events) between LMNA mutation carriers and DCM controls (p=0.5). LMNA mutation carriers presented with atrial fibrillation at a younger age than the DCM controls (47 vs 57 years, p=0.003). Male LMNA mutation carriers presented with clinical manifestations roughly a decade earlier than females. In close follow-up non-sustained ventricular tachycardia was detected in 78% of LMNA mutation carriers. ECG signs of septal remodelling were present in 81% of the LMNA mutation carriers, 21% of the DCM controls and none of the healthy controls giving a high sensitivity and specificity for the standard ECG in distinguishing LMNA mutation carriers from patients with DCM and healthy controls. Conclusions Male LMNA mutation carriers present clinical manifestations at a younger age than females. ECG septal remodelling appears to distinguish LMNA mutation carriers from healthy controls and patients with DCM without LMNA mutations. PMID:28123761

  4. 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.

  5. ECG dispersion mapping predicts clinical deterioration, measured by increase in the Simple Clinical Score.

    LENUS (Irish Health Repository)

    Kellett, J

    2012-01-01

    Objective: ECG dispersion mapping (ECG-DM) is a novel technique that reports abnormal ECG microalternations. We report the ability of ECG-DM to predict clinical deterioration of acutely ill medical patients, as measured by an increase in the Simple Clinical Score (SCS) the day after admission to hospital. Methods: 453 acutely ill medical patients (mean age 69.7 +\\/- 14.0 years) had the SCS recorded and ECGDM performed immediately after admission to hospital. Results: 46 patients had an SCS increase 20.8 +\\/- 7.6 hours after admission. Abnormal micro-alternations during left ventricular re-polarization had the highest association with SCS increase (p=0.0005). Logistic regression showed that only nursing home residence and abnormal micro-alternations during re-polarization of the left ventricle were independent predictors of SCS increase with an odds ratio of 2.84 and 3.01, respectively. Conclusion: ECG-DM changes during left ventricular re-polarization are independent predictors of clinical deterioration the day after hospital admission.

  6. Ral-GTPases: approaching their 15 minutes of fame.

    Science.gov (United States)

    Feig, Larry A

    2003-08-01

    Andy Warhol, the famous pop artist, once claimed that "in the future everyone will be famous for 15 minutes". The same, it seems, can be said of proteins, because at any given time some proteins become more "fashionable" to study than others. But most proteins have been highly conserved throughout millions of years of evolution, which implies that they all have essential roles in cell biology. Thus, each one will no doubt enter the limelight if the right experiment in the right cell type is done. A good example of this is the Ras-like GTPases (Ral-GTPases), which until recently existed in the shadow of their close cousins--the Ras proto-oncogenes. Recent studies have yielded insights into previously unappreciated roles for Ral-GTPases in intensively investigated disciplines such as vesicle trafficking, cell morphology, transcription and possibly even human oncogenesis.

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

    Science.gov (United States)

    Fensli, Rune; Gundersen, Torstein; Snaprud, Tormod; Hejlesen, Ole

    2013-06-01

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

  8. Hypertrophic cardiomyopathy: Prevalence, hypertrophy patterns, and their clinical and ECG findings in a hospital at Qatar

    Directory of Open Access Journals (Sweden)

    Sherif M Helmy

    2011-01-01

    Conclusion: The prevalence of HCM in our population group is 0.13% with a male predominance (12:1. There was a diversity of clinical presentation, ECG abnormalities and patterns of LV hypertrophy among HCM patients.

  9. The 15-Minute Family Interview as a learning strategy for senior undergraduate nursing students.

    Science.gov (United States)

    Holtslander, Lorraine; Solar, Jessica; Smith, Nicole R

    2013-05-01

    Nursing care of families continues to be a challenge within complex and demanding health-care systems. Educational strategies to bridge the theory-practice gap, connecting classroom learning with clinical experiences in undergraduate nursing education, enable students to develop the skills required to form meaningful partnerships with families. This article describes how undergraduate nursing students complete a 15-Minute Family Interview in a clinical practice setting, and document the interview process in a reflective major paper. Students integrate research and theory and identify ways to improve the care of families in the clinical setting while building communication skills and confidence in interacting with families in everyday practice. The implementation of the assignment and the evaluation of the process, including quotes from 10 student papers and 2 clinical faculty members, are discussed. Implications for education and ongoing research are offered.

  10. The clinical application of a PACS-dependent 12-lead ECG and image information system in E-medicine and telemedicine.

    Science.gov (United States)

    Hsieh, Jui-Chien; Lo, Hsiu-Chiung

    2010-08-01

    This study presents a software technology to transform paper-based 12-lead electrocardiography (ECG) examination into (1) 12-lead ECG electronic diagnoses (e-diagnoses) and (2) mobile diagnoses (m-diagnoses) in emergency telemedicine. While Digital Imaging and Communications in Medicine (DICOM)-based images are commonly used in hospitals, the development of computerized 12-lead ECG is impeded by heterogeneous data formats of clinically used 12-lead ECG instrumentations, such as Standard Communications Protocol (SCP) ECG and Extensible Markup Language (XML) ECG. Additionally, there is no data link between clinically used 12-lead ECG instrumentations and mobile devices. To realize computerized 12-lead ECG examination procedures and ECG telemedicine, this study develops a DICOM-based 12-lead ECG information system capable of providing clinicians with medical images and waveform-based ECG diagnoses via Picture Archiving and Communication System (PACS). First, a waveform-based DICOM-ECG converter transforming clinically used SCP-ECG and XML-ECG to DICOM is applied to PACS for image- and waveform-based DICOM file manipulation. Second, a mobile Structured Query Language database communicating with PACS is installed in physicians' mobile phones so that they can retrieve images and waveform-based ECG ubiquitously. Clinical evaluations of this system indicated the following. First, this developed PACS-dependent 12-lead ECG information system improves 12-lead ECG management and interoperability. Second, this system enables the remote physicians to perform ubiquitous 12-lead ECG and image diagnoses, which enhances the efficiency of emergency telemedicine. These findings prove the effectiveness and usefulness of the PACS-dependent 12-lead ECG information system, which can be easily adopted in telemedicine.

  11. 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; Oehler, Martin; Elsässer, Albrecht; Schilling, Meinhard; Maier, Lars

    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...

  12. The feasibility of bench tests for disposable ECG electrode adhesiveness.

    Science.gov (United States)

    Baker, C D; Schoenberg, A A; Booth, H E

    1979-01-01

    The feasibility of recommending one standard bench test that adequately qualifies electrode adhesives for clinical use was examined by UBTL. Small strips, cut from whole, commercially available disposable ECG electrodes, were attached to three types of surfaces, and samples of each type of electrode were peel tested at 15 minutes, 8 hours, and 48 hours after attachment. A program was developed to average, display, and calculate peel strength parameters. Analysis of the data showed that (a) the peel strength of electrodes varied by more than a factor of 10 when measured on human skin, and by more than a factor of 3 when measured on bench test surfaces, and (b) the peel strength of the electrode adhesive strips did not correlate with intact electrode loss on ambulatory subjects. Therefore, UBTL could not recommend one bench test that would measure adhesion performance for all electrode types appropriate for inclusion in an AAMI ECG electrode standard.

  13. Clinical Significance and Changes of ECG in the Patients with Cardiac Deficiency of the Qi and the Yin

    Institute of Scientific and Technical Information of China (English)

    LIN Qi-Shanxi

    2005-01-01

    In order to explore the changes and clinical significance of ECG in the patients with cardiac deficiency of the Qi and Yin, 124 patients with heart diseases were examined by means of ECG. The results showed that the prevalence of left ventricular hypertrophy in cardiac deficiency of the Qi (CDQ) was obviously higher than that of cardiac deficiency of the Yin (CDY). The higher prevalence of tachycardia occurred in the patients with CDY.The prevalence of the Q - T interval prolongation and abnormalities of ST - T segment in the patients with CDY was also higher than that of CDQ. The difference between two groups suggests that the diagnosis of two syndromes by ECG may be of important value.

  14. Multi-lead ECG electrode array for clinical application of electrocardiographic inverse problem.

    Science.gov (United States)

    Hintermuller, Christoph; Fischer, Gerald; Seger, Michael; Pfeifer, Bernhard; Hanser, Friedrich; Modre, Robert; Tilg, Bernhard

    2004-01-01

    Methods for noninvasive imaging of electric function of the heart might become clinical standard procedure the next years. Thus, the overall procedure has to meet clinical requirements as easy and fast application. In this study we propose a new electrode array which improves the information content in the ECG map, considering clinical constraints such as easy to apply and compatibility with routine leads. A major challenge is the development of an electrode array which yields a high information content even for a large interindividual variation in torso shape. For identifying regions of high information content we introduce the concept of a locally applied virtual electrode array. As a result of our analysis we constructed a new electrode array consisting of two L-shaped regular spaced parts and compared it to the electrode array we use for clinical studies upon activation time imaging. We assume that one side effect caused by the regular shape and spacing of the new array be that the reconstruction of electrodes placed on the patients back is simplified. It may be sufficient to record a few characteristic electrode positions and merge them with a model of the posterior array.

  15. Selective detection of 1000 B. anthracis spores within 15 minutes using a peptide functionalized SERS assay.

    Science.gov (United States)

    Farquharson, Stuart; Shende, Chetan; Smith, Wayne; Huang, Hermes; Inscore, Frank; Sengupta, Atanu; Sperry, Jay; Sickler, Todd; Prugh, Amber; Guicheteau, Jason

    2014-12-21

    A surface-enhanced Raman spectroscopy (SERS) assay has been designed to detect Bacillus anthracis spores. The assay consists of silver nanoparticles embedded in a porous glass structure that have been functionalized with ATYPLPIR, a peptide developed to discriminately bind B. anthracis versus other species of Bacillus. Once bound, acetic acid was used to release the biomarker dipicolinic acid from the spores, which was detected by SERS through the addition of silver colloids. This SERS assay was used to selectively bind B. anthracis with a 100-fold selectivity versus B. cereus, and to detect B. anthracis Ames at concentrations of 1000 spores per mL within 15 minutes. The SERS assay measurements provide a basis for the development of systems that can detect spores collected from the air or from water supplies.

  16. Digital and preliminary bedrock geologic map of the Townshend 7.5 x 15 minute quadrangle, Vermont

    Data.gov (United States)

    Vermont Center for Geographic Information — Digital Data from VG98-335A Armstrong, T.R., and Ratcliffe, N.M., 1998, Digital and preliminary bedrock geologic map of the Townshend 7.5 x 15 minute quadrangle,...

  17. Clinical use of the combined Sclarovsky Birnbaum Severity and Anderson Wilkins Acuteness scores from the pre-hospital ECG in ST-segment elevation myocardial infarction

    DEFF Research Database (Denmark)

    Fakhri, Yama; Schoos, Mikkel M; Clemmensen, Peter

    2014-01-01

    This review summarizes the electrocardiographic changes during an evolving ST segment elevation myocardial infarction and discusses associated electrocardiographic scores and the potential use of these indices in clinical practice, in particular the ECG scores developed by Anderson and Wilkins...

  18. Detection of Bacillus spores within 15 minutes by surface-enhanced Raman spectroscopy

    Science.gov (United States)

    Shende, Chetan; Inscore, Frank; Huang, Hermes; Farquharson, Stuart; Sengupta, Atanu

    2012-06-01

    Since the distribution of Bacillus anthracis causing spores through the US Postal System, there has been a persistent fear that biological warfare agents (BWAs) will be used by terrorists against our military abroad and our civilians at home. Despite the substantial effort to develop BWA analyzers, they remain either too slow, produce high falsealarm rates, lack sensitivity, or cannot be fielded. Consequently there remains a need for a portable analyzer that can overcome these limitations as expressed at the 2011 Biological Weapons Convention. To meet this need we have been developing a sample system that selectively binds BWAs and produce surface-enhanced Raman (SER) spectra using portable Raman spectrometers. Here we describe the use of a short peptide ligand functionalized on silver nanoparticles to selectively capture Bacillus cereus spores (a surrogate of B. anthracis) and their subsequent detection by SER spectroscopy. This technique was used to specifically detect B. cereus spores over closely related species like B. subtilis belonging to the same genus within 15 minutes. Sensitivity of the method was demonstrated by detecting 104 B. cereus spores/mL of water. The technology, once developed should prove invaluable for rapid monitoring of BWAs, which will immensely help first responders and emergency personnel in implementing appropriate counter measures.

  19. ECG (image)

    Science.gov (United States)

    ... electrocardiogram (ECG, EKG) is used extensively in the diagnosis of heart disease, ranging from congenital heart disease in infants to myocardial infarction and myocarditis in adults. Several different types of ...

  20. Psychomotor and cognitive effects of 15-minute inhalation of methoxyflurane in healthy volunteers: implication for post-colonoscopy care

    Science.gov (United States)

    Nguyen, Nam Q.; Burgess, Jenna; Debreceni, Tamara L.; Toscano, Leanne

    2016-01-01

    Background and study aims: Colonoscopy with portal inhaled methoxyflurane (Penthrox) is highly feasible with low sedation risk and allows earlier discharge. It is unclear if subjects can return to highly skilled psychomotor skill task shortly after Penthrox assisted colonoscopy. We evaluated the psychomotor and cognitive effects of 15-minute inhalation of Penthrox in adults. Patients and methods: Sixty healthy volunteers (18 to 80 years) were studied on 2 occasions with either Penthrox or placebo in a randomized, double-blind fashion. On each occasion, the subject’s psychomotor function was examined before, immediately, 30, 60, 120, 180 and 240 min after a 15-minute inhalation of studied drug, using validated psychomotor tests (Digit Symbol Substitution Test (DSST), auditory reaction time (ART), eye-hand coordination (EHC) test, trail making test (TMT) and logical reasoning test (LRT). Results: Compared to placebo, a 15-minute Penthrox inhalation led to an immediate but small impairment of DSST (P < 0.001), ART (P < 0.001), EHC (P < 0.01), TMT (P = 0.02) and LRT (P = 0.04). In all subjects, the performance of all 5 tests normalized by 30 minutes after inhalation, and was comparable to that with placebo. Although increasing age was associated with a small deterioration in psychomotor testing performance, the magnitude of Penthrox effects remained comparable among all age groups. Conclusions: In all age groups, a 15-minute Penthrox inhalation induces acute but short-lasting impairment of psychomotor and cognitive performance, which returns to normal within 30 minutes , indicating that subjects who have colonoscopy with Penthrox can return to highly skilled psychomotor skills tasks such as driving and daily work the same day. PMID:27853742

  1. The Clinical Analysis of ECG Diagnosis on Myocardial Infarction%心电图诊断心肌梗死的临床探析

    Institute of Scientific and Technical Information of China (English)

    曹继敏

    2015-01-01

    Objective To analysis the clinical value of ECG diagnosis on myocardial infarction. Methods To analysis the 43 patients cases in myocardial infarction by ECG diagnosis.All the patients cases were chosen from January 2013 to January 2014. Results There were 25 cases (58.14%) patients without typical ECG change and 18 cases (41.86%) with typical ECG changes according to the electrocardiogram.Conclusion The electrocardiogram (ECG) as an aid to diagnosis the myocardial infarction,it is much better than others from repeatability,safe and noninvasive,convenient operation. To adopt the ECG diagnosis combine cardiac enzymes check in patients provide the comprehensive assessment. It will provide the evidence for clinical diagnosis.%目的:探析心电图诊断心肌梗死的临床价值。方法选取2013年1月~2014年1月间我院收治的心肌梗死患者43例给予心电图检测,评估心电图的改变情况。结果心电图显示,25例(58.14%)例无典型的心电图改变,18例(41.86%)有典型的心电图改变。结论心电图作为诊断心肌梗死的辅助方法重复性好、安全无创、操作方便,诊断时需与心肌酶学检查及患者临床症状综合进行评估,为临床诊断提供依据。

  2. Towards the clinical use of concentric electrodes in ECG recordings: influence of ring dimensions and electrode position

    Science.gov (United States)

    Prats-Boluda, G.; Ye-Lin, Y.; Bueno-Barrachina, JM; Rodriguez de Sanabria, R.; Garcia-Casado, J.

    2016-02-01

    To overcome the limited spatial resolution of standard 12-lead ECG recordings, concentric ring electrodes (CRE) have been proposed to provide valuable data for the diagnosis of a wide range of cardiac abnormalities, including infarction and arrhythmia. Although theoretical studies indicate that the dimensions of the CRE regulate the depth of the electric dipoles sensed by these electrodes, this has not been experimentally confirmed. The aim of this work was to analyze the influence of CRE dimensions and position of a wireless multi-CRE sensor node on the cardiac signal recorded. For this, four wireless multichannel ECG recording nodes based on flexible multi-ring electrodes were placed at positions CMV1 (position comparable to V1), CMV2, CMV4R and CMV5; each node providing three bipolar concentric ECG signals (BC-ECG). Standard 12-lead ECG and 12 BC-ECG signals were recorded in 29 volunteers. The results revealed that a ring with an outer diameter of 33.5 mm achieves a balance between the ease-of-use and spatial resolution of smaller electrodes and improved detectability and higher amplitudes of signals from larger ring electrodes. Although a standard 12-lead ECG outperforms BC-ECC recordings in detectability of cardiac waves, if the relative amplitude of the wave is also considered, BC-ECG at CMV1 proved superior at picking up atrial activity. In fact, in most of the BC-ECG signals picked up at CMV1, P1 and P2 atrial activity waves were more clearly identified than in simultaneous 12-Lead ECG signals. Likewise, BC-ECG signals revealed higher spatial resolution in detecting anomalous electrical activity in local regions, such as impaired intraventricular driving, or atrioventricular blocks. Finally, the wireless multi-CRE sensor node provides enhanced comfort and handling to both patient and clinician over wired systems.

  3. Prospective ECG-triggered coronary CT angiography: clinical value of noise-based tube current reduction method with iterative reconstruction.

    Directory of Open Access Journals (Sweden)

    Junlin Shen

    Full Text Available OBJECTIVES: To evaluate the clinical value of noise-based tube current reduction method with iterative reconstruction for obtaining consistent image quality with dose optimization in prospective electrocardiogram (ECG-triggered coronary CT angiography (CCTA. MATERIALS AND METHODS: We performed a prospective randomized study evaluating 338 patients undergoing CCTA with prospective ECG-triggering. Patients were randomly assigned to fixed tube current with filtered back projection (Group 1, n = 113, noise-based tube current with filtered back projection (Group 2, n = 109 or with iterative reconstruction (Group 3, n = 116. Tube voltage was fixed at 120 kV. Qualitative image quality was rated on a 5-point scale (1 = impaired, to 5 = excellent, with 3-5 defined as diagnostic. Image noise and signal intensity were measured; signal-to-noise ratio was calculated; radiation dose parameters were recorded. Statistical analyses included one-way analysis of variance, chi-square test, Kruskal-Wallis test and multivariable linear regression. RESULTS: Image noise was maintained at the target value of 35HU with small interquartile range for Group 2 (35.00-35.03HU and Group 3 (34.99-35.02HU, while from 28.73 to 37.87HU for Group 1. All images in the three groups were acceptable for diagnosis. A relative 20% and 51% reduction in effective dose for Group 2 (2.9 mSv and Group 3 (1.8 mSv were achieved compared with Group 1 (3.7 mSv. After adjustment for scan characteristics, iterative reconstruction was associated with 26% reduction in effective dose. CONCLUSION: Noise-based tube current reduction method with iterative reconstruction maintains image noise precisely at the desired level and achieves consistent image quality. Meanwhile, effective dose can be reduced by more than 50%.

  4. Dimeticone 4% liquid gel found to kill all lice and eggs with a single 15 minute application

    Directory of Open Access Journals (Sweden)

    Burgess Nazma A

    2011-01-01

    Full Text Available Abstract Background Dimeticone 4% lotion is an effective and widely accepted treatment for head louse infestation. However, it is a highly mobile fluid that some people find difficult to apply and is mainly left on the hair for 8 hours or overnight. User preference is for a more manageable and viscous product that can be used with a short application time. Findings This proof of concept study in 41 people investigated dimeticone 4% liquid gel, a product that is easier to apply than the lotion, applied for 15 minutes on two occasions a week apart. We found that head lice were eliminated from all participants following the first application of product. We did not find lice of any stage on any participant during four post treatment assessments and particularly, unlike other treatments, no young nymphs on days 1 and 6 prior to the second treatment, indicating ovicidal as well as pediculicidal activity. Conclusions Dimeticone 4% liquid gel has demonstrated efficacy greater than other similar products and the evidence obtained indicates elimination of head louse infestation with a single 15 minute application. Trial registration Current Controlled Trials ISRCTN59227204

  5. Ecodesign in 15 minutes

    DEFF Research Database (Denmark)

    Huulgaard, Rikke Dorothea

    Strategy Wheel. 2) Update of the ecodesign strategies to the newest knowledge within ecodesign. 3) The spider web function is not part of the digital tool due to budgetary constraints During the development of the ecodesign tool several companies have been involved in the idea phase, and in the prototype...... enterprises (SMEs) which may have less formalised product development processes and are short of resources. This paper presents a recently developed web based ecodesign tool which specifically aims at arousing the interest of SMEs to ecodesign, introduce the concept of ecodesign and guide the SMEs in where...... the knowledge level to 2012 and c) to fit the web based toolbox which had limited budget. These adjustments include: 1) Danish SMEs request inspiration and easy to use tools that do not demand complicated calculations. Hence, focus is placed on the ecodesign strategies and rules of thumbs from the Ecodesign...

  6. Ecodesign in 15 minutes

    DEFF Research Database (Denmark)

    Huulgaard, Rikke Dorothea

    enterprises (SMEs) which may have less formalised product development processes and are short of resources. This paper presents a recently developed web based ecodesign tool which specifically aims at arousing the interest of SMEs to ecodesign, introduce the concept of ecodesign and guide the SMEs in where...... product policy approach. The project focuses on the development of a digital toolbox with ten different tools that supports SMEs in the voluntary environmental efforts. These tools are freely available on the Internet. The tool is inspired by the Ecodesign Strategy Wheel developed in 1997 (Brezet and van...... Hemel, 1997). The Ecodesign strategy wheel visualises the steps and strategies that can be followed in ecodesign and allows the user to compare the environmental performance of different products. Several adjustments have been made in order for the tool a) to fit the target group, b) to update...

  7. ECG Electrocardiogram (For Parents)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old ECG (Electrocardiogram) KidsHealth > For Parents > ECG (Electrocardiogram) Print A ... whether there is any damage. How Is an ECG Done? There is nothing painful about getting an ...

  8. Diagnostic values of chest pain history, ECG, troponin and clinical gestalt in patients with chest pain and potential acute coronary syndrome assessed in the emergency department.

    Science.gov (United States)

    Mokhtari, Arash; Dryver, Eric; Söderholm, Martin; Ekelund, Ulf

    2015-01-01

    In the assessment of chest pain patients with suspected acute coronary syndrome (ACS) in the emergency department (ED), physicians rely on global diagnostic impressions ('gestalt'). The aim of this study was to determine the diagnostic value of the ED physician's overall assessment of ACS likelihood, and the values of the main diagnostic modalities underlying this assessment, namely the chest pain history, the ECG and the initial troponin result. 1,151 consecutive ED chest pain patients were prospectively included. The ED physician's interpretation of the chest pain history, the ECG, and the global likelihood of ACS were recorded on special forms. The discharge diagnoses were retrieved from the medical records. A chart review was carried out to determine whether patients with a non-ACS diagnosis at the index visit had ACS or suffered cardiac death within 30 days. The gestalt was better than its components both at ruling in ("Obvious ACS", LR 29) and at ruling out ("No Suspicion of ACS", LR 0.01) ACS. In the "Strong suspicion of ACS" group, 60% of the patients did not have ACS. A positive TnT (LR 24.9) and an ischemic ECG (LR 8.3) were strong predictors of ACS and seemed superior to pain history for ruling in ACS. In patients with a normal TnT and non-ischemic ECG, chest pain history typical of AMI was not a significant predictor of AMI (LR 1.9) while pain history typical of unstable angina (UA) was a moderate predictor of UA (LR 4.7). Clinical gestalt was better than its components both at ruling in and at ruling out ACS, but overestimated the likelihood of ACS when cases were assessed as strong suspicion of ACS. Among the components of the gestalt, TnT and ECG were superior to the chest pain history for ruling in ACS, while pain history was superior for ruling out ACS.

  9. Clinical Analysis of ECG Changes in the Diagnosis of Hyperkalemia%高血钾症引起心电图改变的临床分析

    Institute of Scientific and Technical Information of China (English)

    王建华

    2014-01-01

    目的:探讨心电图诊断高血钾症的临床价值。方法:对70例高血钾症患者的心电图表现与血清钾浓度的变化进行对比分析。结果:心电图异常改变和血清钾浓度测定存在一定的差异,对肾功能不全所致高血钾症诊断有较好的一致性。当血清钾浓度超过5.5 mmol/L时,心电图表现为帐蓬状高耸T波,基底变窄, Q-T间期缩短,随着血清钾浓度的继续增高,心电图异常发生率亦相应增加,主要是细胞外钾离子浓度增高引起的心电图改变。结论:心电图是评价高血钾症病情程度的重要手段,为临床诊断及治疗提供参考。%Objective: To explore clinical value of electrocardiogram (ECG) in diagnosing hyperkalemia. Methods:The changes of potassium concentrations in the serum and ECG changes of 70 patients with hyperkalemia were compared and analyzed. Results:The manifestation of abnormal ECG is not totally related to serum potassium density, however, it shows a good consistence to hyperkalemia caused by renal failure. When serum potassium den-sity is higher than 5.5mmol/L, ECG reveals a tall T wave with a broad base, a shorten Q-T interval, as serum potassi-um density is increased continually, the incidence of abnormal ECG is raised, which is mainly caused by the density increase of extracellular potassium-ion. Conclusion:ECG is an important method for diagnosing the severity of hy-perkalemia, it could provide reference for clinical diagnosis and treatment.

  10. Digital bedrock geologic map of the Vermont part of the 7.5 x 15 minute Mount Ascutney and Springfield quadrangles, Vermont

    Data.gov (United States)

    Vermont Center for Geographic Information — Digital Data from VG96-733A Walsh, GJ, Armstrong, TR and Ratcliffe, NM, 1996, Digital bedrock geologic map of the Vermont part of the 7.5 x 15 minute Mount Ascutney...

  11. Dynamic link between ECG and clinical data by a CORBA-based query engine and temporal mapping.

    Science.gov (United States)

    Wang, C; Ohe, K; Kaihara, S

    1997-01-01

    It is important to create a dynamic link method to link distributed patient data across multiple hospitals on an "as needed" basis because the pre-defined links (an item of data has a character or group of characters that indicates the storage of another item of data) are difficult to be managed, or can only be established in part, or are not necessary to be pre-defined in many cases, especially in linking the descriptive data such as history data with the corresponding examination data across multiple hospitals. A method of linking electrocardiogram (ECG) with clinical data dynamically in a Common Object Request Broker Architecture (CORBA) environment has been achieved and verified in a real computing environment to approach to this goal. By this method, distributed patient data can be linked dynamically by a CORBA-based query engine and temporal mapping no matter where they are located on the Internet. The necessary temporal information is provided by either computing or human being. Since multiple time-axes for different databases are involved in, some temporal reasoning methods (such as mapping occurrences across temporal contexts and determining bounds for absolute occurrences, etc.) are applied to this study, and a series of temporal mappings including the first mapping, the secondary mapping, the contextual mapping, the extended mapping, the previous mapping and the next mapping are created. In comparison with the pre-defined link, the major strengths of this method are the dynamic link on an "as needed" basis, no limitation of institutional boundaries, easy creation, simplifying the data storage, and the high flexibility, etc.

  12. ANALYSIS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE WITH CLINICAL PARAMETERS, ECG AND ECHO

    Directory of Open Access Journals (Sweden)

    Satish

    2014-10-01

    Full Text Available BACK GROUND: Chronic obstructive pulmonary disease (COPD is a leading cause of morbidity and mortality in countries of high, middle, and low income. Estimates from WHO’s Global Burden of Disease and Risk Factors project show that in 2001, COPD was the fifth leading cause of death in high-income countries, accounting for 3.8% of total deaths, and it was the sixth leading cause of death in nations of low and middle income, accounting for 4·9% of total deaths. OBJECTIVES: 1. To study clinical parameters of chronic obstructive pulmonary disease. 2. To find out Electrocardiographic changes of chronic obstructive pulmonary disease. 3. To confirm with echocardiogram the presence of pulmonary hypertension, tricuspid regurgitation and right heart failure and analyze the incidence of right heart failure and pulmonary hypertension. MATERIALS AND METHODS: Single center hospital based cross sectional study. Patients diagnosed as COPD based on following steps will be included in the study. The patients with cough, sputum production, dyspnoea (wheeze was chosen (sputum AFB negative will be confirmed. Pulmonary function test was done to pick up patients with reduced FEV9 mm, as this is the one of the indication for life long oxygen therapy as per American Thoracic Society (ATS. Out of 72 patients, 12 had coronary artery disease (CAHD as this increases the incidence of cor-pulmonale. CARDIOVASCULAR COMPLICATIONS: Out of 72 patients, 24% developed pulmonary hypertension, 22% developed tricuspid regurgitation, 34% had p-pulmonale, 18% had p-wave amplitude in lead-II + lead-III + lead a VF >9 mm, this is important because this is one of the indication for life long oxygen therapy. 18% had concomitant coronary artery disease (CAHD, this observation is important because systemic inflammation plays enhanced role in atherosclerosis, diabetes mellitus, tumour necrosis factor is increased in COPD patients. CONCLUSION: Pulmonary hypertension was the most common

  13. Clinical application of synchronized EEG-ECG%同步EEG-ECG检查的临床应用

    Institute of Scientific and Technical Information of China (English)

    倪芳

    2010-01-01

    癫痫或拟诊断癫痫的患者在发作或发作间期的,心电图(ECG)异常较常见.目前随着同步脑电图-心电图(EEG-ECG)描记在临床上的应用,对癫痫或拟诊断癫痫患者的异常ECG的认识水平亦在不断提高,一旦癫痫发作可根据同步ECG分析,及早发现恶性心律失常和心脏损害,对预防和筛选癫痫患者中突然的非预期性死亡有重要意义.

  14. ECG De-noising

    DEFF Research Database (Denmark)

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

    2015-01-01

    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...... 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...... their performance. These methods were first compared on two types of simulated noise corrupted ECG signals: Type-I (desired ECG+noise frequencies outside the ECG frequency band) and Type-II (ECG+noise frequencies both inside and outside the ECG frequency band). Subsequently, they were tested on real ECG recordings...

  15. 右位心合并急性心肌梗死的临床心电图分析%Clinical ECG Analysis of Dextrocardia with AMI

    Institute of Scientific and Technical Information of China (English)

    贺茜影; 刘仁光; 王晓梅

    2016-01-01

    Dextrocardia with acute myocardial infarction is clinically rare.Based on the ECG analysis of a case of mirror-image dextrocardia with acute myocardial infarction, this paper discusses the electrocardiogram features of mirror-image dextrocardia, diag-nosis and differential diagnosis of complicated acute myocardial infarction and the related issues.%右位心合并急性心肌梗死临床上较为少见,本文结合1例镜像右位心合并急性心肌梗死的心电图分析,讨论镜像右位心的心电图特点,合并急性心肌梗死的诊断和鉴别诊断有关问题。

  16. 心电图诊断高钾血症的临床应用价值探讨%The Clinical Value of Ecg Diagnosis of Hyperkalemia

    Institute of Scientific and Technical Information of China (English)

    张桂艳

    2016-01-01

    Objective To investigate the clinical value of ecg diagnosis of hyperkalemia. Methods Select our hospital 117 cases of patients with hyperkalemia in research from January 2014 to February 2016, on the basis of different serum K+ concentration was divided into group I 39 cases (5.5~6.9mmol/L), II group of 40 cases (7.0~10.0mmol/L), III group of 38 patients (>10.0mmol/L). For three groups of patients with abnormal ecg diagnosis rate and characteristic performance records and analysis.Results Group I, II, III group patients successive increase the incidence of abnormal ecg, III group had a signiifcantly higher rate of abnormal electrocardiogram (ecg) in patients with group I and II group of patients,P<0.05). 117 cases of patients with hyperkalemia electrocardiogram (ecg) were characterized by tall upright T wave, hyperkalemia patients with different concentration electrocardiogram T wave amplitude and the relationship between serum K+ concentration is not parallel. Group I occasionally occur in patients with high T wave, presents the tent; II group of patients with ST segment showed a downward trend, T wave height, pointed, P wave decreased or disappeared; A wide QRS complex III group patients, and gradually merged in T wave, sine wave shape.Conclusion Using electrocardiogram diagnosis hyperkalaemia, the serum K+ concentration and different abnormal ecg showed that there was a positive correlation between the serum K+ concentration increased, the incidence of abnormal ecg patients also increased, it can be used as a reference in clinical diagnosis and treatment of hyperkalemia, has the very high clinical value.%目的:探讨心电图诊断高钾血症的临床应用价值。方法选取我院2014年1月~2016年2月期间收治的117例高钾血症患者纳入研究,依据不同的血清钾浓度划分为I组39例(5.5~6.9mmol/L)、II组40例(7.0~10.0mmol/L)、III组38例(>10.0mmol/L)。对3组患者的心电图诊断异常率及特征表现

  17. Hyperkalemia Induced Brugada Phenocopy: A Rare ECG Manifestation

    Directory of Open Access Journals (Sweden)

    Muhammad Ameen

    2017-01-01

    Full Text Available Brugada syndrome (BrS is an inherited disorder of cardiac ion channels characterized by peculiar ECG findings predisposing individuals to ventricular arrhythmias, syncope, and sudden cardiac death (SCD. Various electrolyte disturbances and ion channels blocking drugs could also provoke BrS ECG findings without genetic BrS. Clinical differentiation and recognition are essential for guiding the legitimate action. Hyperkalemia is well known to cause a wide variety of ECG manifestations. Severe hyperkalemia can even cause life threatening ventricular arrhythmias and cardiac conduction abnormalities. Most common ECG findings include peaked tall T waves with short PR interval and wide QRS complex. Since it is very commonly encountered disorder, physicians need to be aware of even its rare ECG manifestations, which include ST segment elevation and Brugada pattern ECG (BrP. We are adding a case to the limited literature about hyperkalemia induced reversible Brugada pattern ECG changes.

  18. A Novel Mobile ECG Telemonitoring System.

    Science.gov (United States)

    Wu, Baoming; Zhuo, Yu; Zhu, Xinjian; Yan, Qingguang; Zhu, Lingyun; Li, Gang

    2005-01-01

    This paper introduces a novel mobile ECG telemonitoring system. By means of CDMA1x (GPSOne) mobile telecommunication network, the system can perform "full time and space" monitoring of human ECG signal, and once the signal of the monitored subject departed from its normal ranges, the hospital ECG monitoring center can further localize his/her geographical position and give rescue in the first time. Another feature of the system is its high anti-interference capability. In order to reduce 50Hz and RF interferences during mobile monitoring, which are usual much serious than conventional hospital monitoring, a new active recording technology was proposed and an active ECG recording electrode was designed. The system has passed the clinical test and used in China.

  19. 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.

  20. Utility of the CORD ECG Database in Evaluating ECG Interpretation by Emergency Medicine Residents

    Directory of Open Access Journals (Sweden)

    Wong, Hubert E

    2002-10-01

    Full Text Available OBJECTIVES: Electrocardiograph (ECG interpretation is a vital component of Emergency Medicine (EM resident education, but few studies have formally examined ECG teaching methods used in residency training. Recently, the Council of EM Residency Directors (CORD developed an Internet database of 395 ECGs that have been extensively peer-reviewed to incorporate all findings and abnormalities. We examined the efficacy of this database in assessing EM residents' skills in ECG interpretation. METHODS: We used the CORD ECG database to evaluate residents at our academic three-year EM residency. Thirteen residents participated, including four first-year, four second-year, and five third-year residents. Twenty ECGs were selected using 14 search criteria representing a broad range of abnormalities, including infarction, rhythm, and conduction abnormalities. Exams were scored based on all abnormalities and findings listed in the teaching points accompanying each ECG. We assigned points to each abnormal finding based on clinical relevance. RESULTS: Out of a total of 183 points in our clinically weighted scoring system, first-year residents scored an average of 99 points (54.1% [9 1- 1191, second-year residents 11 1 points (60.4% [97-1261, and third-year residents 130 points (7 1.0% [94- 1501, p = 0.12. Clinically relevant abnormalities, including anterior and inferior myocardial infarctions, were most frequently diagnosed correctly, while posterior infarction was more frequently missed. Rhythm abnormalities including ventricular and supraventricular tachycardias were most frequently diagnosed correctly, while conduction abnormalities including left bundle branch block and atrioventricular (AV block were more frequently missed. CONCLUSION: The CORD database represents a valuable resource in the assessment and teaching of ECG skills, allowing more precise identification of areas upon which instruction should be further focused or individually tailored. Our

  1. Dynamic electrocardiogram (ecg) and conventional electrocardiogram (ecg) in the clinical diagnosis of coronary heart disease patients with the value of myocardial ischemia and arrhythmia%动态心电图与常规心电图在临床诊断冠心病患者心肌缺血及心律失常中的价值

    Institute of Scientific and Technical Information of China (English)

    肖虹

    2015-01-01

    Objective Dynamic electrocardiogram (ecg) and conventional electrocardiogram (ecg) in the clinical diagnosis of coronary heart disease patients with the value of myocardial ischemia and arrhythmia. Methods In March 2014 to November 2014 80 cases of coronary heart disease patients to the hospital to check during the period of dynamic electrocardiogram (ecg) and conventional electrocardiogram (ecg) examination. Compare two groups of two checking methods of detection of myocardial ischemia and arrhythmia. Results Dynamic electrocardiogram (ecg) were significantly higher than the conventional electrocardiogram (ecg), myocardial ischemia group, the difference is statistically significant (P < 0.05);Dynamic electrocardiogram (ecg) short array chamber on speed, atrioventricular block, ventricular/housing contracts before sexual period, sanlian law, atrial/ventricular contracts before sexual period in pairs, such as detection rate of arrhythmia was obviously higher than that of conventional electrocardiogram (ecg), statistically significant difference (P<0.05). Conclusions Dynamic ecg of myocardial ischemia in patients with coronary heart disease detection rate is higher, and the virus infection aslar-pacific perspective, angina pectoris, arrhythmia, coronary heart disease diagnosis, can make early diagnosis and treatment in patients with coronary heart disease (CHD).%目的:探讨动态心电图与常规心电图在临床诊断冠心病患者心肌缺血及心律失常中的价值。方法:对自2014年3月至2014年11月期间来我院检查的80例冠心病患者行动态心电图及常规心电图检查。比较两组两种检查方法的心肌缺血及心律失常的检出率。结果:动态心电图的心肌缺血阳性率明显高于常规心电图组,差异具有统计学意义(P<0.05);动态心电图的短阵室上速、房室传导阻滞、室性/房性期前收缩二、三联律、室性/房性期前收缩成对等心率失常的检出率明显

  2. The clinical and pathologic features of coronary heart disease ECG%冠心病患者150例临床心电图特征和病理特点

    Institute of Scientific and Technical Information of China (English)

    蔡红梅

    2013-01-01

    Objective to investigate the clinical and pathological characters of ecG ofcoronary heart disease.Methods 150 cases of coronary heart disease (CHD) patients(A group) and 12 lead ECG examination, and 55 cases of healthy adult (group B).Results of the 150 cases of coronary heart disease (CHD) patients (A group) and 110 healthy adult (group B) have signiifcant differences in ECG changes (P < 0.05).Conclusion ECG in detecting coronary artery disease (CHD) of fast and effective method.%目的:探讨冠心病的病理和临床心电图特征。方法选择150例冠心病(cHd)患者(a组)12导联心电图检查,与55例健康成人(B组)。结果150例冠心病(cHd)患者(a组)和110例健康成人(B组)心电图的变化有显著差异(P<0.05)。结论心电图检测冠心病(cHd)的快速和有效的方法。

  3. Quasi-Periodic Oscillations of ~ 15 minutes in the Optical Light Curve of the BL Lac S5 0716+714

    CERN Document Server

    Rani, Bindu; Joshi, U C; Ganesh, S; Wiita, Paul J

    2010-01-01

    Over the course of three hours on 27 December 2008 we obtained optical (R-band) observations of the blazar S5 0716+714 at a very fast cadence of 10 s. Using several different techniques we find fluctuations with an approximately 15-minute quasi-period to be present in the first portion of that data at a > 3 sigma confidence level. This is the fastest QPO that has been claimed to be observed in any blazar at any wavelength. While this data is insufficient to strongly constrain models for such fluctuations, the presence of such a short timescale when the source is not in a very low state seems to favor the action of turbulence behind a shock in the blazar's relativistic jet.

  4. Ambulatory ECG-based T-wave alternans monitoring for risk assessment and guiding medical therapy: mechanisms and clinical applications.

    Science.gov (United States)

    Verrier, Richard L; Ikeda, Takanori

    2013-01-01

    Identification of individuals at risk for sudden cardiac death (SCD), the main cause of adult mortality in developed countries, remains a major challenge. The main contemporary noninvasive marker, left ventricular ejection fraction (LVEF), has not proved adequately reliable, as the majority of individuals who die suddenly have relatively preserved cardiac mechanical function. Monitoring of T-wave alternans (TWA), a beat-to-beat fluctuation in ST-segment or T-wave morphology, on ambulatory electrocardiogram (AECG) is an attractive approach on both scientific and clinical grounds. Specifically, TWA's capacity to assess risk for malignant arrhythmias has been shown to rest on sound electrophysiologic principles and AECG-based TWA monitoring can be performed in the flow of routine clinical evaluation. This review addresses: (1) electrophysiologic and ionic mechanisms underlying TWA's predictivity, (2) principles and practical aspects of AECG-based TWA monitoring, (3) clinical evidence supporting this approach to SCD risk stratification, and (4) current and potential applications in guiding medical therapy.

  5. Heart rhythm analysis using ECG recorded with a novel sternum based patch technology

    DEFF Research Database (Denmark)

    Saadi, Dorthe B.; Fauerskov, Inge; Osmanagic, Armin

    2013-01-01

    , reliable long-term ECG recordings. The device is designed for high compliance and low patient burden. This novel patch technology is CE approved for ambulatory ECG recording of two ECG channels on the sternum. This paper describes a clinical pilot study regarding the usefulness of these ECG signals...... for heart rhythm analysis. A clinical technician with experience in ECG interpretation selected 200 noise-free 7 seconds ECG segments from 25 different patients. These 200 ECG segments were evaluated by two medical doctors according to their usefulness for heart rhythm analysis. The first doctor considered...... 98.5% of the segments useful for rhythm analysis, whereas the second doctor considered 99.5% of the segments useful for rhythm analysis. The conclusion of this pilot study indicates that two channel ECG recorded on the sternum is useful for rhythm analysis and could be used as input to diagnosis...

  6. High-frequency ECG

    Science.gov (United States)

    Tragardh, Elin; Schlegel, Todd T.

    2006-01-01

    The standard ECG is by convention limited to 0.05-150 Hz, but higher frequencies are also present in the ECG signal. With high-resolution technology, it is possible to record and analyze these higher frequencies. The highest amplitudes of the high-frequency components are found within the QRS complex. In past years, the term "high frequency", "high fidelity", and "wideband electrocardiography" have been used by several investigators to refer to the process of recording ECGs with an extended bandwidth of up to 1000 Hz. Several investigators have tried to analyze HF-QRS with the hope that additional features seen in the QRS complex would provide information enhancing the diagnostic value of the ECG. The development of computerized ECG-recording devices that made it possible to record ECG signals with high resolution in both time and amplitude, as well as better possibilities to store and process the signals digitally, offered new methods for analysis. Different techniques to extract the HF-QRS have been described. Several bandwidths and filter types have been applied for the extraction as well as different signal-averaging techniques for noise reduction. There is no standard method for acquiring and quantifying HF-QRS. The physiological mechanisms underlying HF-QRS are still not fully understood. One theory is that HF-QRS are related to the conduction velocity and the fragmentation of the depolarization wave in the myocardium. In a three-dimensional model of the ventricles with a fractal conduction system it was shown that high numbers of splitting branches are associated with HF-QRS. In this experiment, it was also shown that the changes seen in HF-QRS in patients with myocardial ischemia might be due to the slowing of the conduction velocity in the region of ischemia. This mechanism has been tested by Watanabe et al by infusing sodium channel blockers into the left anterior descending artery in dogs. In their study, 60 unipolar ECGs were recorded from the entire

  7. A method of ECG template extraction for biometrics applications.

    Science.gov (United States)

    Zhou, Xiang; Lu, Yang; Chen, Meng; Bao, Shu-Di; Miao, Fen

    2014-01-01

    ECG has attracted widespread attention as one of the most important non-invasive physiological signals in healthcare-system related biometrics for its characteristics like ease-of-monitoring, individual uniqueness as well as important clinical value. This study proposes a method of dynamic threshold setting to extract the most stable ECG waveform as the template for the consequent ECG identification process. With the proposed method, the accuracy of ECG biometrics using the dynamic time wraping for difference measures has been significantly improved. Analysis results with the self-built electrocardiogram database show that the deployment of the proposed method was able to reduce the half total error rate of the ECG biometric system from 3.35% to 1.45%. Its average running time on the platform of android mobile terminal was around 0.06 seconds, and thus demonstrates acceptable real-time performance.

  8. Prevalence and clinical significance of incidental cardiac findings in non-ECG-gated chest CT scans; Praevalenz und klinische Bedeutung inzidenteller Herzbefunde im nicht EKG-getriggerten Thorax-CT

    Energy Technology Data Exchange (ETDEWEB)

    Quentin, M.; Kroepil, P.; Lanzman, R.S.; Blondin, D.; Miese, F.; Scherer, A. [Heinrich-Heine-Universitaet Duesseldorf, Institut fuer Radiologie, Duesseldorf (Germany); Steiner, S. [Klinikum der Heinrich-Heine-Universitaet Duesseldorf, Klinik fuer Kardiologie, Pneumologie und Angiologie, Duesseldorf (Germany); Choy, G.; Abbara, S. [Massachusetts General Hospital, Harvard Medical School, Cardiovascular Imaging Section, Boston (United States)

    2011-01-15

    The purpose of this study was to evaluate the prevalence and clinical significance of incidental cardiac findings in non-ECG-gated chest CT. Non-ECG-gated chest CT examinations of 300 patients were retrospectively analyzed for incidental cardiac findings. Subsequently, these findings were evaluated for their clinical relevance by a cardiologist. A total of 107 out of 300 examined patients had 174 incidental cardiac findings including coronary calcification (90), aortic/mitral valve calcification (42), iatrogenic changes (23), pericardial effusion (6), dilatation of the heart (4), myocardial changes (3), thrombus in the left ventricle (2), constrictive pericarditis (2) and atrial myxoma (1). Of the cardiac findings 51% were described in the written report and in 53 out of the 107 patients the cardiac findings were unknown. Newly detected incidental findings from 8 patients were rated as clinically significant: pericardial effusion (4), constrictive pericarditis (1), thrombus in the left ventricle (1), atrial myxoma (1) and dilatation of the heart (1). Incidental cardiac findings are frequent in non-ECG-gated chest CT and may have a high clinical relevance. (orig.) [German] Ziel dieser Studie war es, die Praevalenz und klinische Bedeutung inzidenteller Herzbefunde im nicht EKG-getriggerten Thorax-CT ohne primaer kardiale Fragestellung zu evaluieren. Dreihundert nicht EKG-getriggerte Thorax-CT-Untersuchungen wurden retrospektiv bzgl. inzidenteller Herzbefunde analysiert. Die klinische Bedeutung wurde von einem Kardiologen bewertet. Von 300 Patienten hatten 107 insgesamt 174 Herzbefunde: Koronarsklerose (90), Aorten-/Mitralklappenverkalkung (42), iatrogene Veraenderungen (23), Perikarderguss (6), Herzvergroesserung (4), Myokardpathologien (3), Perikardverkalkungen (2), Thrombus im linken Ventrikel (2) und Myxom (1). Im radiologischen Bericht wurden 51% aller Herzbefunde beschrieben. Bei 53 der 107 Patienten mit Herzbefund waren diese klinisch nicht bekannt. Als

  9. The programmable ECG simulator.

    Science.gov (United States)

    Caner, Candan; Engin, Mehmet; Engin, Erkan Zeki

    2008-08-01

    This paper reports the design and development of Digital Signal Controller (DSPIC)-based ECG simulator intended to use in testing, calibration and maintenance of electrocardiographic equipment, and to support biomedical engineering students' education. It generates all 12 healthy ECG derivation signals having a profile that varies with heart rate, amplitude, and different noise contamination in a manner which reflects true in vivo conditions. The heart rate can be set at the range of 30 to 120 beats/minute in four steps. The noise and power line interference effects can be set at the range of 0 to 20 dB in three steps. Since standard commercially available electronic components were used to construct the prototype simulator, the proposed design was also relatively inexpensive to produce.

  10. 36例心电监护下种植手术临床观察%Clinical Observation of 36 Cases with Implant Surgery under ECG Monitoring

    Institute of Scientific and Technical Information of China (English)

    高巍; 张晓; 姜霞

    2013-01-01

    目的:在心电监护辅助下对心脑血管疾病患者进行种植牙植入手术,观察临床效果.方法:对36例患有心脑血管疾病者,在心电监护下进行种植外科手术,观察并监测手术过程,麻醉前后、手术前后的血压、心率变化,进行对比分析.结果:36例患者全部顺利完成手术,其中男性19例,女性17例,平均年龄67.9岁(45~81岁),平均手术时间51 min(20~134) min.麻醉前、后,术前、术后血压、心率较为平稳,心电图(67.7%)变化不大.结论:对患有心脑血管疾病、全身条件较差者,在心电监护下进行种植外科手术是比较可行的方式.%Objective:In the electrocardiographic monitoring conditions,to observe the clinical effect of the oral implant surgery patients with cardio-cerebral-vascular disease.Methods:36 patients with cardio-cerebro-vascular diseases were observed and monitored blood pressure,heart rate changes before,during and after implant surgery.Results:All 36 patients successfully completed surgery,19 cases were male and 17 females,mean age 67.9years (45 to 81 years old),average operation time was 51min (20-134min).Before and after anesthesia,pre and post operation the blood pressure and heart rate were steady,little change in electrocardiogram (67.7%).Conclusion:For patients suffering from cardio-cerebro-vascular diseases,with systemic conditions worse,ECG monitoring is a more feasible way to give implant surgery.

  11. Spatio-temporal distribution of Saharan dust source activations inferred from 15-minute MSG-SEVIRI observations and its links to meteorological processes (Invited)

    Science.gov (United States)

    Schepanski, K.; Tegen, I.

    2009-12-01

    Mineral dust aerosol emitted from arid and semi-arid areas impacts on the weather and climate system by affecting e.g. radiation fluxes and nutrient cycles. The emission of dust particles depend strongly on surface wind velocity and turbulent fluxes as well as on surface characteristics like surface texture and vegetation cover. To estimate the effect of dust aerosol, detailed knowledge on the spatio-temporal distribution of active dust sources is necessary. As dust sources are mostly located over remote areas satellite observations are suitable for localizing active dust sources. Thereby the accuracy of determining dust sources from such an indirect method is limited by the temporal resolution and the ambiguities of the retrieval. A 1°x1° map on the spatial and temporal (3-hourly) distribution of dust source activations (DSA) over North Africa is compiled starting in March 2006. For dust source identification 15-minute Meteosat Second Generation (MSG) infra-red (IR) dust index images are used based on brightness temperature measurements by the Spinning enhanced Visible and Infra-Red Imager (SEVIRI) at 8.7 µm, 10.8 µm and 12.0 µm. This data set has been used (1) to identify most active dust source areas, and (2) to investigate on the temporal distribution of occurring dust source activations. Over the Sahara Desert 65% of dust sources becomes active during 06-09 UTC pointing towards an important role of the break-down of the nocturnal low-level jet (LLJ) for dust mobilization besides other meteorological features like density currents, haboobs, and cyclones. Furthermore the role of the nocturnal LLJ for dust mobilization over the Sahara is investigated by weather observations and a modelling study. DSA observations of the last 3.5 years indicate an interannual variability in frequencies of local dust source activations. The causes of this variability will be analyzed with respect to corresponding atmospheric conditions.

  12. Evaluation of alcaftadine 0.25% ophthalmic solution in acute allergic conjunctivitis at 15 minutes and 16 hours after instillation versus placebo and olopatadine 0.1%

    Directory of Open Access Journals (Sweden)

    Jack V Greiner

    2011-01-01

    Full Text Available Jack V Greiner1,2, Kimberly Edwards-Swanson3, Avner Ingerman41Schepens Eye Research Institute, Boston, MA; 2Department of Ophthalmology, Harvard Medical School, Boston, MA; 3Johnson & Johnson Consumer and Personal Products Worldwide, Skillman, NJ; 4Ora Inc, Andover, MA, USAPurpose: To evaluate the effectiveness of alcaftadine 0.05%, 0.1%, and 0.25% ophthalmic solutions in treating the signs and symptoms of allergic conjunctivitis when compared with olopatadine hydrochloride 0.1% and placebo using the conjunctival allergen challenge (CAC model.Methods: One hundred and seventy subjects were randomized and 164 subjects completed all visits. CAC was performed to determine and confirm subjects’ eligibility at visits 1 and 2, respectively. The CAC was repeated at visit 3 (day 0 ± 3, 16 hours after study medication instillation, and at visit 4 (day 14 ± 3, 15 minutes after instillation. Ocular itching and conjunctival redness were evaluated after an allergen challenge, along with several secondary endpoints.Results: Alcaftadine 0.25% and olopatadine 0.1% treatments exhibited significantly lower mean scores compared with placebo for ocular itching and conjunctival redness at visits 3 and 4. Most adverse events were self-limiting and mild in severity. No serious treatment-related adverse events occurred.Conclusion: Treatment with alcaftadine 0.25% ophthalmic solution resulted in mean differences of >1 unit (ocular itching and approximately >1 unit (conjunctival redness, which was significant (P < 0.001 compared with placebo treatment. All doses of alcaftadine were safe and well tolerated in the population studied.Keywords: alcaftadine, allergic conjunctivitis, conjunctival allergen challenge

  13. 心电图检查在心房纤颤诊断中的临床价值分析%Analysis of the Clinical Value of ECG Examination in the Diagnosis of Atrial Fibrillation

    Institute of Scientific and Technical Information of China (English)

    彭国翠

    2015-01-01

    目的:探讨心电图检查应用在心房纤颤诊断中的临床价值。方法:筛选2013年10月-2014年1月笔者所在医院收治的心房纤颤患者310例作为研究对象。所有患者均经临床症状检查且均符合心房纤颤的诊断标准,对所有患者进行心电图检查并依据心电图结果进行诊断及病情评价,探讨心电图检查在心房纤颤诊断中的价值。结果:心电图的确诊符合率为98.06%(304/310),持续性房颤确诊符合率为98.27%(171/174),阵发性房颤为98.91%(91/92),永久性房颤为95.45%(42/44),并发风湿性心脏病符合率为91.30%(21/23),甲亢心脏病符合率为100%(11/11),高血压性心脏病符合率为92.68%(38/41),肺心病符合率为100%(16/16),与临床证实结果比较差异均无统计学意义(P>0.05)。结论:应用心电图检查心房纤颤患者可提高该病的临床确诊率,同时可实现对病情及并发症的准确评价,从而指导临床心房纤颤的治疗。%Objective:To investigate the clinical value of ECG examination application on diagnosis of atrial fibrillation.Method:310 patients with atrial fibrillation from October 2013 to January 2014 in our hospital were screened as research subjects.All patients were diagnosed by clinical examination and met the diagnostic criteria for atrial fibrillation,all patients were examined by ECG and based on ECG examination results for diagnosis and disease evaluation,and investigated the value of ECG in the diagnosis of atrial fibrillation.Result:The accordance rate of ECG diagnose was 98.06%(304/310),the diagnosis coincidence rate of persistent atrial fibrillation was 98.27%(171/174),the diagnosis coincidence rate of paroxysmal atrial fibrillation was 98.91%(91/92),the diagnosis coincidence rate of permanent atrial fibrillation was 95.45%(42/44),the coincidence rate of rheumatic heart disease was 91.30%(21/23),the coincidence rate of hyperthyroid heart disease was 100%(11/11),the

  14. Clinical Characters of ECG in Later Gestational Diabetes%妊娠期糖尿病患者妊娠晚期心电图临床特点分析

    Institute of Scientific and Technical Information of China (English)

    余海英; 梁珊瑚; 刘士春

    2014-01-01

    Objective:To analyse the clinical characters of ECG in later gestational diabetes women.Method:Randomly selected 72 cases of gestational diabetes were as group GDM1,gestational diabetes and pregnancy induced hypertension in patients with 35 cases of GDM2 group,and 100 patients with normal pregnant women as control group,were in the hospital antenatal electrocardiogram examination,the ECG analysis.Result:Normal late pregnancy rate was 26.0%, the abnormal ecg GDM1 group was 34.7%,GDM2 group was 45.7%,the comparison group difference was statistically significant (P<0.05),sinus tachycardia is most common among them,followed by ST-T change and short PR interval period.Conclusion:The abnormal rate of ECG is high in the later gestational women, and corralate with the pregnant complication,so ECG is necessary,especially to high-risk pregnant.%目的:探讨妊娠期糖尿病患者妊娠晚期心电图改变特点。方法:随机选取妊娠期糖尿病患者72例为GDM1组,妊娠期糖尿病合并妊娠期高血压疾病患者35例为GDM2组,并以正常妊娠孕妇100例作为对照组,均在入院产前行心电图检查,对其心电图情况进行分析。结果:正常孕晚期心电图异常率为26.0%,GDM1组为34.7%,GDM2组为45.7%,三组比较差异有统计学意义(P<0.05),其中窦性心动过速最常见,其次为ST-T改变及短PR间期。结论:妊娠晚期心电图异常发生率较高,并且与妊娠并发症及严重性具有一定的相关性,对于高龄尤其有合并症的患者应常规检查心电图。

  15. 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.

  16. 远程心电监测诊断心律失常及心肌缺血的临床价值%Clinical value of remote ECG monitoring in diagnosis of arrhythmia and myocardial ischemia

    Institute of Scientific and Technical Information of China (English)

    郭琳

    2015-01-01

    目的:评估远程心电监测在心律失常、心肌缺血患者临床诊断中的应用价值。方法选取2012年5月至2014年5月于河南大学淮河医院门诊接受远程心电图监测的64例确诊为心脏不适或心脏病的患者,同时对所有患者实施12导联心电图检查,选取其中40例患者做24 h动态心电图检查,对比观察常规导联心电图检查、24 h动态心电图及远程心电监测在诊断心律失常、心肌缺血方面的检出率。结果64例患者远程心电监测提示心律失常52例,占81.3%,其心律失常检出率明显高于常规心电图的59.4%,两种不同诊断方式比较差异有统计学意义(P0.05)。结论为提高心律失常及心肌缺血的检出率,可将远程动态监测作为常规心电图检查与24 h动态心电图检查的辅助诊断手段。%Objective To evaluate the application value of remote ECG monitoring in clinical diagnosis of arrhyth-mia, myocardial ischemia. Methods Sixty-four patients diagnosed with heart disease or heart discomfort accepted remote ECG monitoring in huaihe hospital of Henan university from May 2012 to May 2014 were selected, they were all given the 12 lead ECG examination, and 40 patients given the 24 h dynamic electrocardiogram, the positive rate of myocardial ische-mia and arrhythmia comparative diagnosed by routine lead electrocardiogram inspection, detection rate 24 h dynamic elec-trocardiogram and remote ECG monitoring were compared. Results Among the 64 cases, 52 cases of arrhythmia detected by the remote ECG, accounting for 81. 3%, arrhythmia detection rate was significantly higher than that of conventional ECG (59. 4%), the difference was significant (P0. 05). Conclusions In order to improve detectable rate of arrhythmia and myocardial ischemia, remote dynamic moni-toring can be as auxiliary diagnostic means routine ECG examination and 24 h dynamic electrocardiogram examination.

  17. 心电图检查在冠心病诊断中的临床价值%The clinical value of ECG in the diagnosis of coronary heart disease

    Institute of Scientific and Technical Information of China (English)

    郝翠平

    2016-01-01

    目的 探讨冠心病患者心电图(ECG)和冠状动脉造影检查结果的相关性,分析心电图检查在冠心病诊断中的临床价值.方法 回顾性分析本院收治的116例疑似冠心病患者的临床资料,以冠状动脉造影检查结果作为诊断冠心病的金标准,分析心电图检查诊断冠心病的准确性.采用Gensini评分判定冠状动脉病变的严重程度,分析心电图检查结果与冠心病病变程度相关性.结果 116例疑似冠心病患者中,87例患者确诊为冠心病;心电图检查诊断冠心病的灵敏度为78.16%、特异性为68.96%、阳性预测值为77.27%、阴性预测值为32.14%,但中度和重度冠心病患者的心电图异常率明显高于轻度冠心病患者,差异具有统计学意义(P<0.05).结论 心电图异常与冠状动脉病变程度具有一定的相关性,对于心电图异常的疑似冠心病患者,冠状动脉造影检查对于冠心病的诊断具有重要的临床价值.%Objective To study the correlation between electrocardiogram (ECG) and coronary angiography in patients with coronary heart disease,and analyze the value of electrocardiogram in the diagnosis of coronary heart disease.Methods Retrospectively analyzed the clinical data of 116 patients with suspected coronary heart disease,with coronary angiography results as golden standard for diagnosing,analyzed the accuracy of ECG in diagnosis of coronary heart disease.Evaluated the severity degree of coronary atherosclerosis with Gensini score,analyzed the correlation between ECG and coronary heart disease.Results In 116 cases of suspected coronary heart disease,87 patients were diagnosed by coronary angiography.In the diagnosis of coronary heart disease by ECG,the sensitivity was 78.16%,the specificity was 68.96%,the positive predictive value was 77.27%,and the negative predictive value was 32.14%.But the positive rate of ECG was higher in patients with moderate and severe coronary heart disease than

  18. Variable threshold method for ECG R-peak detection.

    Science.gov (United States)

    Kew, Hsein-Ping; Jeong, Do-Un

    2011-10-01

    In this paper, a wearable belt-type ECG electrode worn around the chest by measuring the real-time ECG is produced in order to minimize the inconvenient in wearing. ECG signal is detected using a potential instrument system. The measured ECG signal is transmits via an ultra low power consumption wireless data communications unit to personal computer using Zigbee-compatible wireless sensor node. ECG signals carry a lot of clinical information for a cardiologist especially the R-peak detection in ECG. R-peak detection generally uses the threshold value which is fixed. There will be errors in peak detection when the baseline changes due to motion artifacts and signal size changes. Preprocessing process which includes differentiation process and Hilbert transform is used as signal preprocessing algorithm. Thereafter, variable threshold method is used to detect the R-peak which is more accurate and efficient than fixed threshold value method. R-peak detection using MIT-BIH databases and Long Term Real-Time ECG is performed in this research in order to evaluate the performance analysis.

  19. Advanced DSP Technique to Remove Baseline Noise from ECG Signal

    Directory of Open Access Journals (Sweden)

    Kanhaiya Kumar

    2012-06-01

    Full Text Available Heart diseases, which are one of the death reasons, are among the several serious problems in this century and as per the latest survey, 60% of the patients die due to Heart problems. In 2011, 10 crores people are suffering from heart diseases in India. Many individuals remain unaware of the symptoms of heart attack or dismiss possible symptoms as being unrelated or not important enough to visit a doctor. Early diagnosis and medical treatment of heart diseases can prevent sudden death of the patient. One of the ways to diagnose heart diseases is to use Electrocardiogram (ECG signals. ECG measures electrical potentials on the body surface via contact electrodes. However, timely and accurate detection of arrhythmias is a complex decision-making process for a cardiologist due to contamination of ECG signals with different frequencies of noise. For reliable interpretation of real-time ECGs, computer based techniques on digital signal processing (DSP of ECG waveform have been reported. ECG signals are non-stationary signals including valuable clinical informations, but frequently these informations are corrupted by noise. Many tools, methods and algorithms based on signal processing theory have been proposed and implemented. In this paper, advanced digital signal processing is carried out in Matlab environment. And the present work basically focuses on implementation and evaluation of methods to remove noise from ECG signal.

  20. 高钾血症应用心电图诊断的临床分析%Clinical Analysis of ECG in the Diagnosis of Hyperkalemia

    Institute of Scientific and Technical Information of China (English)

    毛洁; 彭伊

    2016-01-01

    目的:研究并分析高钾血症应用心电图诊断的效果。方法:收集高钾血症患者共85例,根据患者的血清钾浓度分为对照组56例和观察组29例,对照组患者的血清钾浓度为5.5~6.5 mmol/L,观察组的血清钾浓度为6.5 mmol/L以上,患者均接受心电图诊断,将诊断结果与实验室诊断结果进行对比。结果:观察组与实验室诊断结果的符合率显著高于对照组(P<0.05)。结论:在高钾血症患者的治疗过程中,心电图诊断具有迅速、操作简单的优势,患者的血钾浓度与心电图的改变有着密切的关联性,随着血钾浓度水平的不断升高,会逐渐加重患者心电图的异常表现,值得推广应用。%Objective:To study and analyze the effect of ECG diagnosis in the application of hyperkalemia. Method: A total of 85 cases of hyperkalemia were collected,according to the patient's serum potassium concentration they were divided into the control group(n=56) and the observation group(n=29),patients of the control group with serum potassium concentration were 5.5-6.5 mmol/L,the observation group was above 6.5 mmol/L.Patients underwent ECG diagnosis,diagnosis results and laboratory diagnosis results were compared. Result:The coincidence rate of the observation group and the laboratory diagnosis result was significantly higher than that of the control group(P<0.05).Conclusion:In the treatment of patients with hyperkalemia and ECG diagnosis with rapid,simple operation advantage and patients serum potassium concentration and ECG change has a close correlation,along with rising of the concentration of blood potassium level,gradually increase theelectrocardiogram in patients with abnormal performance.It is worthy of popularization and application.

  1. 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.

  2. Brugada ECG patterns in athletes.

    Science.gov (United States)

    Chung, Eugene H

    2015-01-01

    Brugada syndrome is responsible for up to 4% of all sudden cardiac deaths worldwide and up to 20% of sudden cardiac deaths in patients with structurally normal hearts. Heterogeneity of repolarization and depolarization, particularly over the right ventricle and the outflow tract, is responsible for the arrhythmogenic substrate. The coved Type I ECG pattern is considered diagnostic of the syndrome but its prevalence is very low. Distinguishing between a saddle back Type 2 Brugada pattern and one of many "Brugada-like" patterns presents challenges especially in athletes. A number of criteria have been proposed to assess Brugada ECG patterns. Proper precordial ECG lead placement is paramount. This paper reviews Brugada syndrome, Brugada ECG patterns, and recently proposed criteria. Recommendations for evaluating a Brugada ECG pattern are provided.

  3. [Management of pacemaker patients by bathtub ECG].

    Science.gov (United States)

    Mizukami, H; Togawa, T; Toyoshima, T; Ishijima, M

    1989-01-01

    We evaluated the efficacy of a new method for recording electrocardiogram (ECG) of pacemaker patients in bathtub (bathtub ECG). ECG from the pacemaker implanted patients in the bathtub with tap water was recorded through three silver/silver chloride electrodes (4 x 4 cm) fitted on the inside wall of bathtub. Electric signal was connected to the isolated amplifier and recorded on the strip chart recorder. Contrast to the conventional method for recording standard ECG, bathtub ECG does not require body surface electrodes and is recorded at patients home. Although the amplitude of bathtub ECG was reduced approximately to a quarter of standard ECG, cardiac arrhythmia can be easily interpreted by bathtub ECG. In patients with pacemaker system, the amplitude of the pacing pulse recorded by bathtub ECG was much larger than that of QRS complex recorded by standard ECG. Therefore, we conclude that bathtub ECG would be a suitable method to follow up patients with pacemaker system.

  4. β-受体阻滞剂干预更年期妇女心电图变化的临床价值%Clinical significance of beta-receptor blocker intervention on ECG changes in climacteric women

    Institute of Scientific and Technical Information of China (English)

    贺桦; 李针; 渠红霞; 孟凡琳; 王兵

    2015-01-01

    目的:探讨β-受体阻滞剂干预更年期妇女心电图变化的临床价值。方法选取无器质性疾病但有心电图改变的更年期妇女62例,经患者知情同意按照数字表法随机分为治疗组31例,予以β-受体阻滞剂治疗3周;另31例为对照组,不给予任何治疗。观察治疗前后2组间及治疗组心电图指标(心率、心律、ST-T)的改变。结果(1)经β-受体阻滞剂治疗3周后,2组平均心率、心律、ST-T改变(除ST上斜外)比较差异均有统计学意义(P<0.05)。(2)治疗组治疗前后比较,成对房早、ST上斜和T波倒置虽有改变,但差异无统计学意义(P>0.05);其余指标均有明显改变,差异有统计学意义(P<0.05)。结论β-受体阻滞剂应用于心电图改变的更年期妇女有一定的临床价值。%Objective To investigate the clinical significance of beta-receptor blocker intervention on ECG changes in climac-teric women.Methods Sixty-two subjects of climacteric women without organic diseases but with ECG changes were chosen and ran-domly divided into 2 groups:the control group(n=32)and the treatment group(n=30).The subjects of the control group were not giv-en any treatment, while the subjects of the treatment group were given treatment of beta-receptor blocker intervention for 3 weeks.ECG changes ( heart rate, rhythm and ST-T changes) were detected both before and after treatment, and then, comparisons were made be-tween the groups and within the groups.Results ( 1 ) After 3 weeks of beta-receptor blocker intervention, significant ECG changes could be noted in heart rate, rhythm and ST-T changes ( except ST cable) in the subjects of the treatment group, with statistical signifi-cance, when comparisons were made between the 2 groups (P0.05).There were significant changes in the remaining parameters, with statistical significance (P<0.05). Conclusion Beta-receptor blocker had its clinical

  5. 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.

  6. Clinical Research into ECG in Diagnosis of MI and Related Arteries%心电图判断心肌梗塞及其相关动脉的临床研究

    Institute of Scientific and Technical Information of China (English)

    尹雪艳; 廖新学; 杨艳萍

    2001-01-01

    目的:探讨心电图对心肌梗塞诊断的临床应用价值及由此间接推断梗塞相关动脉的可靠性。方法:以经心电图确诊的有 Q性心梗 47例为实验组,非心梗 45例为对照组,用单项筛检法研究心电图,二维超声心动图对心梗诊断的可靠性;以实验组冠状动脉造影作对照,探讨以心电图定位的心梗间接推断梗塞相关动脉的可靠性。结果: (1)心电图对有 Q性心梗的定性诊断敏感性 90.4%,特异性 86.7%。 (2)心电图及超声心动图对前壁、前间壁心梗定位诊断的敏感性分别为 87.2%和 97.1%,特异性为 86.7%及 71.1%。对下壁、后壁及右室心梗的定位诊断感性不如前壁。 (3)心电图定位的前壁心梗梗塞相关动脉为左前降支为主的病变,下壁、后壁及右室梗塞的相关动脉为右冠主干及左回旋支病变。结论:心电图以其无创、可靠、重复性好等优点在心肌梗塞的定性定位诊断方面有不可替代的价值,由此可间接判断梗塞相关动脉,具有临床实用价值。若常规加打 V3R~ V6R、 V7~ V9导联则可提高诊断符合率。%Objective: To research into the clinical value of ECG in diagnosis of AML, and to indirectly assess the reliability of infarct in related arteries by ECG.Methods:Taking 47 cases with AMI as the test group and 45 cases without AMI as the control group to study the diagnostic value by using both ECG and UCG. At the same tine,the coronary angiography of the test group was taken as a cuntrol factor to indirectly predict the IRA through Localization of AMI in ECG.Results:(1) The qualitative diagnosis of ECG on the QMI showed that the sensitivity and the specificity were 90.4% and 86.7% ;(2)The qualitative diagnosis of ECG and UCG on the anterior and interval walls of the MI showed that the sensitivity were 87.2% and 97.1% , and the specificity were 86.7% and 71.2% respectively.However, the

  7. IMPORTANCE OF 15 LEAD ECG

    Directory of Open Access Journals (Sweden)

    Bhargav

    2014-10-01

    Full Text Available BACKGROUND AND OBJECTIVES: Posterior wall myocardial infarction is not uncommon acute myocardial infarction and has got its own therapeutic and prognostic implications. Management of Posterior wall myocardial infarction differs from inferior wall myocardial infarction alone. The presence of posterior wall myocardial infarction is known to increase the incidence of cardiogenic shock, arrhythmias and conduction blocks in case of myocardial infarction. Hence the present study was taken up to find out the incidence, clinical profile and complications of posterior wall myocardial infarction in a rural hospital using simple non-invasive investigations like 15 lead electrocardiography and echocardiography. METHODS: A prospective study was conducted on 50 patients of inferior wall myocardial infarction out of 228 Acute Myocardial Infarction proved by ECG standard and posterior leads (v7, v8, v9 were taken at the time of admission and repeated as necessary. A detailed case history was taken and a detailed physical examination was done at the time of admission and during follow up. For recording ECG 12 lead (3 standard leads, 3 augmented limb leads, 6 precordial leads machine was used. The recordings were made at 25 mm/ sec. speed and 1mV=10mm. Posterior leads were taken by using 3 precordial leads fixing on the posterior axillary (v7, infrascapular (v8 and paraspinal (v9 regions all in a same line with the 5th ICS anteriorly. RESULTS: Out of 50 cases of inferior wall myocardial infarction (IWMI studied only 13 (26% had ST elevation in posterior leads indicating posterior wall myocardial infarction (PWMI. Our study showed that complications and mortality was higher in patients of IWMI with PWMI compared to IWMI without PWMI. Out of 50 patients 33 (66% were males indicating a male predominance. Syncope was present in 18% of PWMI and 14% in overall IWMI. Palpitation was seen in 53% of PWMI and 21% of IWMI without PWMI. Smoking history was present in 14% of

  8. Capacitive ECG system with direct access to standard leads and body surface potential mapping.

    Science.gov (United States)

    Oehler, Martin; Schilling, Meinhard; Esperer, Hans Dieter

    2009-12-01

    Capacitive electrodes provide the same access to the human electrocardiogram (ECG) as galvanic electrodes, but without the need of direct electrical skin contact and even through layers of clothing. Thus, potential artifacts as a result of poor electrode contact to the skin are avoided and preparation time is significantly reduced. Our system integrates such capacitive electrodes in a 15 sensor array, which is combined with a Tablet PC. This integrated lightweight ECG system (cECG) is easy to place on the chest wall and allows for simultaneous recordings of 14 ECG channels, even if the patient is slightly dressed, e.g., with a t-shirt. In this paper, we present preliminary results on the performance of the cECG regarding the capability of recording body surface potential maps (BSPMs) and obtaining reconstructed standard ECG leads including Einthoven, Goldberger and, with some limitations, Wilson leads. All signals were measured having the subject lie in a supine position and wear a cotton shirt. Signal quality and diagnostic ECG information of the extracted leads are compared with standard ECG measurements. The results show a very close correlation between both types of ECG measurements. It is concluded that the cECG lends itself to rapid screening in clinically unstable patients.

  9. A Comparison of IIR and Wavelet Filtering for Noise Reduction of the ECG.

    Science.gov (United States)

    Sørensen, Js; Johannesen, L; Grove, Usl; Lundhus, K; Couderc, J-P; Graff, C

    2010-09-26

    This study compares the ability to preserve information and reduce noise contaminants on the ECG for five wavelet filters and three IIR filters. Two 3-lead Holter ECGs were used. White Gaussian Noise was added to the first ECG in increments of 10% coverage. The second ECG contained alternating muscle transients and noise-free segments. Computation times and SNR improvements for different noise coverages were calculated and compared. RMS errors were calculated from noise-free segments on the ECG with transient muscle noise. Wavelet filters improved SNR more than IIR filters when the signal coverage was more than 50% noise. In contrast, the computation times were shorter for IIR filters (6 s) than for wavelet filters (88 s). On the ECG with transient muscle noise there was a trade-off in performance between wavelet and IIR filtering. In a clinical setting where the amount of noise is unknown, using IIR filters appears to be preferred for consistent performance.

  10. ECG movement artefacts can be greatly reduced with the aid of a movement absorbing device

    DEFF Research Database (Denmark)

    Harrison, Adrian Paul; Wandall, Kirsten; Thorball, Jørgen

    2007-01-01

    Accurate ECG signal analysis can be confounded by electric lead, and/or electrode movements varying in origin from, for example, hiccups, tremor or patient restlessness. ECG signals recorded using either a conventional electrode holder or with the aid of an electrode holder capable of absorbing...... movement artefacts, were measured on a healthy human subject. Results show a greatly improved stability of the ECG signal recorded using an electrode holder capable of absorbing movement artefacts during periods of lead disturbance, and highlight the movement artefacts that develop when the recording lead...... of a conventional ECG electrode holder is tugged or pulled during theperiod of monitoring. It is concluded that the new design of ECG electrode holder will not only enable clearer signal recordings for clinical assessment, but will reduce the ECG artefacts associated with the transportation of patients, and may...

  11. The Telemetric and Holter ECG Warehouse (THEW): the first three years of development and research.

    Science.gov (United States)

    Couderc, Jean-Philippe

    2012-01-01

    The Telemetric and Holter ECG Warehouse (THEW) hosts more than 3700 digital 24-Holter ECG recordings from 13 independent studies. In addition to the ECGs, the repository includes patient information in separate clinical database with content varying according to the study focus. In its third year of activities, the THEW database has been accessed by researchers from 37 universities and 16 corporations located in 16 countries worldwide. Twenty publications were released primarily focusing on the development and validation of ECG-based technologies. This communication describes the content of the databases of the repository with brief summary of the research and development projects completed using these data.

  12. 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

  13. An adaptive Kalman filter for ECG signal enhancement.

    Science.gov (United States)

    Vullings, Rik; de Vries, Bert; Bergmans, Jan W M

    2011-04-01

    The ongoing trend of ECG monitoring techniques to become more ambulatory and less obtrusive generally comes at the expense of decreased signal quality. To enhance this quality, consecutive ECG complexes can be averaged triggered on the heartbeat, exploiting the quasi-periodicity of the ECG. However, this averaging constitutes a tradeoff between improvement of the SNR and loss of clinically relevant physiological signal dynamics. Using a bayesian framework, in this paper, a sequential averaging filter is developed that, in essence, adaptively varies the number of complexes included in the averaging based on the characteristics of the ECG signal. The filter has the form of an adaptive Kalman filter. The adaptive estimation of the process and measurement noise covariances is performed by maximizing the bayesian evidence function of the sequential ECG estimation and by exploiting the spatial correlation between several simultaneously recorded ECG signals, respectively. The noise covariance estimates thus obtained render the filter capable of ascribing more weight to newly arriving data when these data contain morphological variability, and of reducing this weight in cases of no morphological variability. The filter is evaluated by applying it to a variety of ECG signals. To gauge the relevance of the adaptive noise-covariance estimation, the performance of the filter is compared to that of a Kalman filter with fixed, (a posteriori) optimized noise covariance. This comparison demonstrates that, without using a priori knowledge on signal characteristics, the filter with adaptive noise estimation performs similar to the filter with optimized fixed noise covariance, favoring the adaptive filter in cases where no a priori information is available or where signal characteristics are expected to fluctuate.

  14. Development of a portable wireless system for bipolar concentric ECG recording

    Science.gov (United States)

    Prats-Boluda, G.; Ye-Lin, Y.; Bueno Barrachina, J. M.; Senent, E.; Rodriguez de Sanabria, R.; Garcia-Casado, J.

    2015-07-01

    Cardiovascular diseases (CVDs) remain the biggest cause of deaths worldwide. ECG monitoring is a key tool for early diagnosis of CVDs. Conventional monitors use monopolar electrodes resulting in poor spatial resolution surface recordings and requiring extensive wiring. High-spatial resolution surface electrocardiographic recordings provide valuable information for the diagnosis of a wide range of cardiac abnormalities, including infarction and arrhythmia. The aim of this work was to develop and test a wireless recording system for acquiring high spatial resolution ECG signals, based on a flexible tripolar concentric electrode (TCE) without cable wiring or external reference electrode which would make more comnfortable its use in clinical practice. For this, a portable, wireless sensor node for analogue conditioning, digitalization and transmission of a bipolar concentric ECG signal (BC-ECG) using a TCE and a Mason-likar Lead-I ECG (ML-Lead-I ECG) signal was developed. Experimental results from a total of 32 healthy volunteers showed that the ECG fiducial points in the BC-ECG signals, recorded with external and internal reference electrode, are consistent with those of simultaneous ML-Lead-I ECG. No statistically significant difference was found in either signal amplitude or morphology, regardless of the reference electrode used, being the signal-to-noise similar to that of ML-Lead-I ECG. Furthermore, it has been observed that BC-ECG signals contain information that could not available in conventional records, specially related to atria activity. The proposed wireless sensor node provides non-invasive high-local resolution ECG signals using only a TCE without additional wiring, which would have great potential in medical diagnosis of diseases such as atrial or ventricular fibrillations or arrhythmias that currently require invasive diagnostic procedures (catheterization).

  15. Analysis of ECG Using Filter Bank Approach

    Directory of Open Access Journals (Sweden)

    S. Thulasi Prasad

    2014-01-01

    Full Text Available In recent years scientists and engineers are facing several problems in the biomedical field. However Digital Signal Processing is solving many of those problems easily and effectively. The signal processing of ECG is very useful in detecting selected arrhythmia conditions from a patient’s electrocardiograph (ECG signals. In this paper we performed analysis of noisy ECG by filtering of 50 Hz power line interference using an adaptive LMS notch filter. This is very meaningful in the measurement of biomedical events, particularly when the recorded ECG signal is very weak. The basic ECG has the frequency range from 5 Hz to 100 Hz. It becomes difficult for the Specialist to diagnose the diseases if the artifacts are present in the ECG signal. Methods of noise reduction have decisive influence on performance of all electro-cardio-graphic (ECG signal processing systems. After removing 50/60 Hz powerline interference, the ECG is lowpass filtered in a digital FIR filter. We designed a Filter Bank to separate frequency ranges of ECG signal to enhance the occurrences QRS complexes. Later the positions of R-peaks are identified and shown plotted. The result shows the ECG signal before filtering and after filtering with their frequency spectrums which clearly indicates the reduction of the power line interference in the ECG signal and a filtered ECG with identified R-peaks.

  16. Thyroid hormones concentrations and ECG picture in the dog.

    Science.gov (United States)

    Pasławska, U; Noszczyk-Nowak, A; Kungl, K; Bioły, K; Popiel, J; Nicpoń, J

    2006-01-01

    Disorders of the thyroid gland activity are the most commonly encountered disturbances of endocrine origin in the dog. Hypo- or hyperthyroidism may disturb the function of the cardiovascular system and cause arrhythmias. The aim of this study was to evaluate the influence of thyroid gland activity on electrocardiogram (ECG) picture in the dog by comparing ECG curves of healthy dogs, dogs with hypothyroidism and dogs with cardiac insufficiency caused by endocardiosis of the mitral valve. The study was performed on 38 dogs, patients of the Department of Internal and Parasitic Diseases with Clinic for Horses, Dogs and Cats in Wrocław. The animals were assigned to 3 groups: Group I--control group, 13 clinically healthy dogs; Group II--14 dogs with diagnosed cardiac insufficiency caused by endocardiosis of the mitral valve; Group III--11 dogs with hypothyroidism. Clinical examination of the animals was conducted according to the following pattern: anamnesis, general clinical examination, cardiological examination (ECG, USG of the heart) and laboratory analysis (triacylglycerydes, cholesterol, T3, T4, FT4). In this study, the significant influence of thyroid gland activity on ECG picture of the evaluated dogs was found. In the dogs with hypothyroidism a decrease in the sino-atrial node activity was observed, which led to decreased heart rate. In dogs with hypothyroidism, the innerheart conduction was reduced, which was demonstrated by prolongation of the P wave, QRS complex and the QT interval.

  17. 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…

  18. Non-contact ECG monitoring

    Science.gov (United States)

    Smirnov, Alexey S.; Erlikh, Vadim V.; Kodkin, Vladimir L.; Keller, Andrei V.; Epishev, Vitaly V.

    2016-03-01

    The research is dedicated to non-contact methods of electrocardiography. The authors describe the routine of experimental procedure and suggest the approach to solving the problems which arise at indirect signal recording. The paper presents the results of experiments conducted by the authors, covers the flow charts of ECG recorders and reviews the drawbacks of filtering methods used in foreign equivalents.

  19. 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...

  20. Analysis of ECG Tp and Te interval on the clinical value of coronary heart disease%心电图 Tp-Te 间期对冠心病患者的临床诊断价值

    Institute of Scientific and Technical Information of China (English)

    丁莹; 刘海; 张民

    2014-01-01

    目的:探讨心电图T波峰末( Tp-Te )间期对冠心病患者的临床诊断价值。方法回顾性分析2010年5月-2013年5月入住的110例心脏病患者的临床资料,其中62例为冠心病患者( CHD组),48例为非冠心病患者(非CHD组)。对2组患者Tp-Te 间期、Tp-Te 间期离散度及J波进行测量,并对心电图进行记录。结果(1)2组V2导联Tp-Te 间期、V6导联Tp-Te 间期比较,差异具有统计学意义( P <0|.05, P <0.01),但Tp-Te 间期离散度比较,差异无统计学意义( P >0.05);(2)不同支数冠状动脉狭窄组间V2导联Tp-Te 间期、V6导联Tp-Te间期及Tp-Te 间期离散度比较,差异均无统计学意义( P >0.05);(3)冠心病患者中,有J波组与无J波组V2导联Tp-Te 间期、V6导联Tp-Te 间期及Tp-Te 间期离散度比较,差异均无统计学意义( P >0.05)。结论心电图Tp-Te 间期对冠心病的诊断具有一定的临床价值;冠脉狭窄支数或缺血性J波对Tp-Te 间期并非惟一的影响因素。%Objective To explore the electrocardiogram T wave end ( Tp-Te ) interval of coronary heart disease in clinical diagnostic value .Methods Retrospective analysis of May 2010 to May 2013 110 cases clinical data of inpatients with heart disease , including 62 cases of coronary heart disease ( CHD group ) , 48 cases of non-coronary heart disease ( non-CHD group).On two groups of patients T p-Te interval, Tp-Te interval dispersion and J wave measurements , and ECG recording.Re-sults (1) 2 group V2 lead Tp-Te interval, V6 lead Tp-Te interval value, the difference was statistically significant ( P 0.05);(2)Diffe rent counts coronary stenosis group V2 lead Tp-Te interval, V6 lead Tp-Te interval and Tp-Te interval dispersion,the difference was not statistically significant ( P >0.05) ;(3)Coronary artery disease patients, J wave group and non-J wave group V2 J wave ECG Tp-Te interval, V6 lead Tp-Te interval

  1. Left Ventricular Hypertrophy: An allometric comparative analysis of different ECG markers

    Science.gov (United States)

    Bonomini, M. P.; Ingallina, F.; Barone, V.; Valentinuzzi, M. E.; Arini, P. D.

    2011-12-01

    Allometry, in general biology, measures the relative growth of a part in relation to the whole living organism. Left ventricular hypertrophy (LVH) is the heart adaptation to excessive load (systolic or diastolic). The increase in left ventricular mass leads to an increase in the electrocardiographic voltages. Based on clinical data, we compared the allometric behavior of three different ECG markers of LVH. To do this, the allometric fit AECG = δ + β (VM) relating left ventricular mass (estimated from ecocardiographic data) and ECG amplitudes (expressed as the Cornell-Voltage, Sokolow and the ECG overall voltage indexes) were compared. Besides, sensitivity and specifity for each index were analyzed. The more sensitive the ECG criteria, the better the allometric fit. In conclusion: The allometric paradigm should be regarded as the way to design new and more sensitive ECG-based LVH markers.

  2. Design of Low Power Algorithms for Automatic Embedded Analysis of Patch ECG Signals

    DEFF Research Database (Denmark)

    Saadi, Dorthe Bodholt

    The diagnosis of cardiac arrhythmias often depends on information from long-term ambulatory electrocardiographic (ECG) monitoring. For several decades, these recordings have been obtained by wired Holter recorders. However, to overcome some of the known disadvantages of the old technologies......, several different cable-free wireless patch-type ECG recorders have recently reached the market. One of these recorders is the ePatch designed by the Danish company DELTA. The extended monitoring period available with the patch recorders has demonstrated to increase the diagnostic yield of outpatient ECG...... monitoring. Furthermore, the patch recorders facilitate the possibility of outpatient ECG monitoring in new clinically relevant areas, e.g. telemedicine monitoring of cardiac patients in their homes. Some of these new applications could benefit from real-time embedded interpretation of the recorded ECGs...

  3. ECG by mobile technologies.

    Science.gov (United States)

    Guzik, Przemyslaw; Malik, Marek

    Mobile electrocardiographs consist of three components: a mobile device (e.g. a smartphone), an electrocardiographic device or accessory, and a mobile application. Mobile platforms are small computers with sufficient computational power, good quality display, suitable data storage, and several possibilities of data transmission. Electrocardiographic electrodes and sensors for mobile use utilize unconventional materials, e.g. rubber, e-textile, and inkjet-printed nanoparticle electrodes. Mobile devices can be handheld, worn as vests or T-shirts, or attached to patient's skin as biopatches. Mobile electrocardiographic devices and accessories may additionally record other signals including respiratory rate, activity level, and geolocation. Large-scale clinical studies that utilize electrocardiography are easier to conduct using mobile technologies and the collected data are suitable for "big data" processing. This is expected to reveal phenomena so far inaccessible by standard electrocardiographic techniques.

  4. ECG Feature Extraction Techniques - A Survey Approach

    CERN Document Server

    Karpagachelvi, S; Sivakumar, M

    2010-01-01

    ECG Feature Extraction plays a significant role in diagnosing most of the cardiac diseases. One cardiac cycle in an ECG signal consists of the P-QRS-T waves. This feature extraction scheme determines the amplitudes and intervals in the ECG signal for subsequent analysis. The amplitudes and intervals value of P-QRS-T segment determines the functioning of heart of every human. Recently, numerous research and techniques have been developed for analyzing the ECG signal. The proposed schemes were mostly based on Fuzzy Logic Methods, Artificial Neural Networks (ANN), Genetic Algorithm (GA), Support Vector Machines (SVM), and other Signal Analysis techniques. All these techniques and algorithms have their advantages and limitations. This proposed paper discusses various techniques and transformations proposed earlier in literature for extracting feature from an ECG signal. In addition this paper also provides a comparative study of various methods proposed by researchers in extracting the feature from ECG signal.

  5. Clinical observation of ECG in diagnosis of acute myocardial infarction with bundle branch block%心电图诊断急性心肌梗死合并束支阻滞的临床观察

    Institute of Scientific and Technical Information of China (English)

    吴梅花

    2016-01-01

    Objective Discussion of electrocardiographic diagnosis of acute myocardial infarction clinical significance of bundle branch block..Methods From March 2014 to December 2015,72 patients with acute myocardial infarction in patients with bundle branch block as the object of study,after ECG for patients,respectively,traditional programmes and Sgarbossa diagnosis scheme for diagnostic purposes. Observation and comparison of two diagnosis results of the programme.Results The two methods in the negative predictive and diagnostic sensitivity of no significant difference but Sgarbossa positive predictive diagnosis method of rate and specificity than conventional methods.Conclusion Sgarbossa judge diagnosis,can effectively improve the accuracy of electrocardiogram in diagnosis of myocardial infarction.%目的:讨论心电图诊断急性心肌梗死合并束支阻滞的临床意义。方法选取2014年3月至2015年12月,72例患有急性心肌梗死合并束支阻滞的患者为研究对象,对患者进行心电图检查之后,分别以传统诊断方案和Sgarbossa诊断方案进行诊断。观察和比较两中诊断方案的结果。结果两种方法在阴性预测率和诊断敏感性的比较上没有显著差异,但是用Sgarbossa诊断方法的阳性预测率和特异性明显高于传统方法。结论应用Sgarbossa诊断方案进行判断,可以有效的提高心电图诊断心肌梗死的准确率。

  6. The amount of viable and dyssynchronous myocardium is associated with response to cardiac resynchronization therapy: initial clinical results using multiparametric ECG-gated [{sup 18}F]FDG PET

    Energy Technology Data Exchange (ETDEWEB)

    Lehner, Sebastian; Uebleis, Christopher; Haug, Alexander; Bartenstein, Peter [University of Munich, Department of Nuclear Medicine, Munich (Germany); Schuessler, Franziska; Kaeaeb, Stefan; Estner, Heidi [University of Munich, Medical Department I, Munich (Germany); Van Kriekinge, Serge D.; Germano, Guido [UCLA, Cedars-Sinai Medical Center, Los Angeles and David Geffen School of Medicine, Los Angeles, CA (United States); Hacker, Marcus [Medical University of Vienna, Division of Nuclear Medicine, Department of Biomedical Imaging and Image-guided Theraphy, Vienna (Austria)

    2013-12-15

    There is still a significant amount of patients who do not sufficiently respond to cardiac resynchronization therapy (CRT). Previous studies demonstrated that the amount of dyssynchronous myocardium was predictive of response to CRT. Otherwise, non-response is frequently associated with high amounts of scar tissue. The combination of these parameters might yield a more accurate prediction of response. We hypothesized that the probability of a CRT response increases with the presence of high amounts of ''viable and dyssynchronous'' myocardium. A total of 19 patients (17 male, 61 {+-} 10 years) underwent ECG-gated [{sup 18}F]fluorodeoxyglucose (FDG) myocardial positron emission tomography (PET) before CRT device implantation and were followed for 6 months. Response to CRT was defined as clinical improvement of at least one New York Heart Association (NYHA) class in combination with left ventricular (LV) ejection fraction (EF) improvement of >5 %. Twelve responders (71 %) and seven non-responders (29 %) were identified. For each patient bullseye maps of FDG uptake and phase analysis were calculated (QPS/QGS 2012, Cedars-Sinai, Los Angeles, CA, USA) and fused. Amounts of myocardium representing ''viable and synchronous'', ''scar and synchronous'', viable and dyssynchronous or ''scar and dyssynchronous'' myocardium were quantified by planimetric measurements of the fused bullseye maps. Responders by definition showed significant decrease in NYHA class and significant increase of LVEF. Furthermore, a significantly higher amount of viable and dyssynchronous myocardium was found as compared to non-responders (21 {+-} 13 % vs 6 {+-} 5 %; p < 0.05). Combined assessment of myocardial viability and LV dyssynchrony is feasible using multiparametric [{sup 18}F]FDG PET and could improve conventional response prediction criteria for CRT. (orig.)

  7. Are ECG monitoring recommendations before prescription of QT-prolonging drugs applied in daily practice?

    DEFF Research Database (Denmark)

    Warnier, Miriam Jacoba; Rutten, Frans Hendrik; Souverein, Patrick Cyriel

    2015-01-01

    PURPOSE: Monitoring of the QT duration by electrocardiography (ECG) prior to treatment is frequently recommended in the label of QT-prolonging drugs. It is, however, unknown how often general practitioners in daily clinical practice are adhering to these risk-minimization measures. We assessed...... the frequency of ECG measurements in patients where haloperidol was initiated in primary care. METHODS: Patients (≥18 years) with a first prescription of haloperidol in the UK Clinical Practice Research Datalink (2009-2013) were included. The proportion of ECGs made was determined in two blocks of 4 weeks......: during the exposure period when haloperidol was initiated, and during the control period, 1 year before. Conditional logistic regression analysis was applied to calculate the relative risk of having an ECG in the exposure period compared with the control period. Subgroup analyses were performed to assess...

  8. Prevalence of Brugada-type ECG pattern and early ventricular repolarization pattern in Tunisian athletes

    Directory of Open Access Journals (Sweden)

    Ouali S

    2011-04-01

    Full Text Available Sana Ouali1, Helmi Ben Salem1, Sami Hammas1, Elyes Neffeti1, Fahmi Remedi1, Abdallah Mahdhaoui2, Essia Boughzela1, Rafik Mankai31Department of Cardiology, Sahloul Hospital, Sousse, Tunisia; 2Department of Cardiology, Farhat Hached, Sousse, Tunisia; 3Central Sports Medicine Centre of El Menzah, TunisiaIntroduction: No data regarding the prevalence of the Brugada-type electrocardiogram (ECG pattern and the early ventricular repolarization pattern (ERP in the North African population were available. The aims of this study were to determine the frequency of Brugada-type ECG pattern and ERP in Tunisia and to evaluate ECG descriptors of ventricular repolarization in a population of athletes.Methods: Over a 2-year period, resting 12-lead ECG recordings were analyzed from athletes (n = 540; 348 males; age 18.3 ± 2.4 years. Brugada-type ECG pattern was defined as Type 1, 2, or 3, and ERP was characterized by an elevation of the J point in the inferior and/or lateral leads. The population was divided into three groups of athletes: ERP group; Brugada-type ECG pattern group; and control group, with neither ERP nor Brugada ECG pattern. Clinical and electrocardiographic parameters were compared among the study groups.Results: Nine subjects (1.66% had a Brugada-type ECG pattern. None of them had the coved-type, 3 (0.6% had the Type 2, and 6 (1.1% had the Type 3. All subjects were asymptomatic. A Brugada-type ECG pattern was observed in seven males. No female had the Type 2 Brugada ECG pattern. ECG parameters were similar among Brugada-type ECG pattern and control athletes. ERP (119 subjects, 22% was obtained in 98 males. Heart rate was lower, the QRS duration shorter and QT and Tpeak–Tend intervals were longer in ERP than control groups.Conclusion: The results indicate that the frequency of the Brugada-type ECG pattern and ERP were respectively 1.66% and 22.00% in athletes, being more prevalent in males. The ERP group experienced shorter QRS duration and

  9. 低钾血症致心律失常的心电图特点与临床分析%Hypokalemia Induced Arrhythmia ECG Characteristics and Clinical Analysis

    Institute of Scientific and Technical Information of China (English)

    雷卫红

    2013-01-01

    目的:探讨低钾血症致心律失常的心电图特点与临床的关系。方法分析160例低钾血症所致心律失常的低钾病因、临床表现、血钾浓度与心律失常关系及心律失常的转归。结果低钾血症所致的心律失常多见于急性失钾的青壮年,血钾降低的程度与心律失常的发生率,其差异有高度显著性P<0.01;血钾越低,心律失常发生率越高。结论除重症室性心律失常外,通常的病例经积极有效补钾后,病情好转快,预后好,不急于使用抗心律失常药物,以避免引发更严重的心律失常。%Objective To study the hypokalemia induced arrhythmia characteristics and the relationship between clinical electrocardiogram (ECG). Methods Analysis of 160 cases with arrhythmia induced by hypokalemia low potassium etiology, clinical manifestation, potassium concentration relation with arrhythmia and outcome of cardiac arrhythmias.Results The cardiac arrhythmias of hypokalemia caused by acute potassium loss of young adults, see more at the extent of the potassium lower and the incidence of arrhythmia, highly signifi cant difference (P < 0.01); Potassium is lower, the higher the incidence of arrhythmia. Conclusion In addition to the severe ventricular arrhythmia, usually cases after positive and effective complement potassium, improved fast, prognosis is good, don't rush to the use of anti-arrhythmic drugs, in order to avoid caused more serious arrhythmia.

  10. Contact dermatitis caused by ECG electrode paste.

    Science.gov (United States)

    Cochran, R J; Rosen, T

    1980-12-01

    A case of contact dermatitis caused by ECG electrode cream is presented and the pertinent literature is reviewed. Our patient was found to be allergic to propylene glycol. Patch-testing remains an invaluable tool in the evaluation of patients suspected of being allergic to ECG paste, creams, and gels.

  11. [A wireless ECG monitor based on ARM].

    Science.gov (United States)

    Fan, Ai-Hua; Bian, Chun-Hua; Ning, Xin-Bao; He, Ai-Jun; Zhuang, Jian-Jun; Wu, Xu-Hui

    2008-11-01

    This paper presents a novel monitor which uses ARM controller AT91SAM7S64 as its main processor, LCM (Liquid Crystal Display Module) for displaying ECG waves, SD (Secure Digital memory) card for data storage and RF module PTR8000 for radio data transmission. This portable monitor boasts alarm function for abnormality and can provide dynamic ECG monitoring for patients.

  12. Expert knowledge for computerized ECG interpretation

    NARCIS (Netherlands)

    J.A. Kors (Jan)

    1992-01-01

    textabstractIn this study, two main questions are addressed: (1) Can the time consuming and cumbersome development and refinement of (heuristic) ECG classifiers be alleviated, and (2) Is it possible to increase diagnostic performance of ECG computer programs by combining knowledge from multiple sour

  13. 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.

  14. Heritability of ECG Biomarkers in the Netherlands Twin Registry Measured from Holter ECGs

    Science.gov (United States)

    Hodkinson, Emily C.; Neijts, Melanie; Sadrieh, Arash; Imtiaz, Mohammad S.; Baumert, Mathias; Subbiah, Rajesh N.; Hayward, Christopher S.; Boomsma, Dorret; Willemsen, Gonneke; Vandenberg, Jamie I.; Hill, Adam P.; De Geus, Eco

    2016-01-01

    Introduction: The resting ECG is the most commonly used tool to assess cardiac electrophysiology. Previous studies have estimated heritability of ECG parameters based on these snapshots of the cardiac electrical activity. In this study we set out to determine whether analysis of heart rate specific data from Holter ECGs allows more complete assessment of the heritability of ECG parameters. Methods and Results: Holter ECGs were recorded from 221 twin pairs and analyzed using a multi-parameter beat binning approach. Heart rate dependent estimates of heritability for QRS duration, QT interval, Tpeak–Tend and Theight were calculated using structural equation modeling. QRS duration is largely determined by environmental factors whereas repolarization is primarily genetically determined. Heritability estimates of both QT interval and Theight were significantly higher when measured from Holter compared to resting ECGs and the heritability estimate of each was heart rate dependent. Analysis of the genetic contribution to correlation between repolarization parameters demonstrated that covariance of individual ECG parameters at different heart rates overlap but at each specific heart rate there was relatively little overlap in the genetic determinants of the different repolarization parameters. Conclusions: Here we present the first study of heritability of repolarization parameters measured from Holter ECGs. Our data demonstrate that higher heritability can be estimated from the Holter than the resting ECG and reveals rate dependence in the genetic—environmental determinants of the ECG that has not previously been tractable. Future applications include deeper dissection of the ECG of participants with inherited cardiac electrical disease. PMID:27199769

  15. Ecg Monitoring Using Android Smart App

    Directory of Open Access Journals (Sweden)

    Pooja Pawar

    2016-04-01

    Full Text Available This paper describes a mixed-signal ECG system that is capable of implementing configurable functionality with low-power consumption for portable ECG monitoring applications. A low-voltage and high performance analog front-end extracts 3-channel ECG signals and single channelelectrode-tissue-impedance (ETI measurement with high signalquality. Design effective and low cost solution for ECG machine. . Wave forms of ECG can be observed on Android smartphones. Its availability and cost is significant and affordable. That makes this system upgradable and effective for every class of people.. Our system is portable so anyone can handle this in a simple way with android based smartphone. It doesn’t cost much. It reduces work, efforts and expenses for patients and their relatives.

  16. [Wireless ECG measurement system with capacitive coupling].

    Science.gov (United States)

    Aleksandrowicz, Adrian; Walter, Marian; Leonhardt, Steffen

    2007-04-01

    This paper describes a measurement system that captures an electrocardiogram (ECG) using capacitively coupled electrodes. The measurement system was integrated into an off-the-shelf office chair (so-called "Aachen SmartChair"). Whereas for classical ECG measurement adhesive is used to attach conductively coupled electrodes to bare skin, the system presented allows ECG measurement through clothing without direct skin contact. Furthermore, a ZigBee communication module was integrated to allow wireless transmission of ECG data to a PC or an ICU patient monitor. For system validation, classical ECG using conductive electrodes was obtained simultaneously. First measurement results, including variations of cloth thickness and material, are presented and some of the system-specific problems of this approach are discussed.

  17. ECG signal denoising via empirical wavelet transform.

    Science.gov (United States)

    Singh, Omkar; Sunkaria, Ramesh Kumar

    2016-12-29

    This paper presents new methods for baseline wander correction and powerline interference reduction in electrocardiogram (ECG) signals using empirical wavelet transform (EWT). During data acquisition of ECG signal, various noise sources such as powerline interference, baseline wander and muscle artifacts contaminate the information bearing ECG signal. For better analysis and interpretation, the ECG signal must be free of noise. In the present work, a new approach is used to filter baseline wander and power line interference from the ECG signal. The technique utilized is the empirical wavelet transform, which is a new method used to compute the building modes of a given signal. Its performance as a filter is compared to the standard linear filters and empirical mode decomposition.The results show that EWT delivers a better performance.

  18. III Lead ECG Pulse Measurement Sensor

    Science.gov (United States)

    Thangaraju, S. K.; Munisamy, K.

    2015-09-01

    Heart rate sensing is very important. Method of measuring heart pulse by using an electrocardiogram (ECG) technique is described. Electrocardiogram is a measurement of the potential difference (the electrical pulse) generated by a cardiac tissue, mainly the heart. This paper also reports the development of a three lead ECG hardware system that would be the basis of developing a more cost efficient, portable and easy to use ECG machine. Einthoven's Three Lead method [1] is used for ECG signal extraction. Using amplifiers such as the instrumentation amplifier AD620BN and the conventional operational amplifier Ua741 that would be used to amplify the ECG signal extracted develop this system. The signal would then be filtered from noise using Butterworth filter techniques to obtain optimum output. Also a right leg guard was implemented as a safety feature to this system. Simulation was carried out for development of the system using P-spice Program.

  19. 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

    2017-02-16

    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.

  20. REMOVAL OF 50HZ POWERLINE INTERFERENCE FOR QUALITY DIAGNOSIS OF ECG SIGNAL

    Directory of Open Access Journals (Sweden)

    SIGMA BARICK

    2013-05-01

    Full Text Available The power line interference (50/60 Hz is the main source of noise in most of bio-electric signal. In this paper second order infinite impulse response (IIR notch filter, adaptive notch filtering technique with LMS (least mean square algorithm and Discrete Wavelet transform method has been proposed for the removal of power line interference from ECG signal. Different ECG signals from MIT/BIH arrhythmia database are used with added power-line interference noise which is common in ECG signal. The result is analyzed using MATLABsoftware. Basically two synthesis parameters MSE and SNR have been used. The prime aim of this paper is to adapt the discrete wavelet transform (DWT to improve the ECG signal quality for better clinical diagnosis. The proposed method shows improvement in output SNR is 97.60%.

  1. 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.

  2. Fetal Electrocardiogram (fECG Gated MRI

    Directory of Open Access Journals (Sweden)

    Martyn N.J. Paley

    2013-08-01

    Full Text Available We have developed a Magnetic Resonance Imaging (MRI-compatible system to enable gating of a scanner to the heartbeat of a foetus for cardiac, umbilical cord flow and other possible imaging applications. We performed radiofrequency safety testing prior to a fetal electrocardiogram (fECG gated imaging study in pregnant volunteers (n = 3. A compact monitoring device with advanced software capable of reliably detecting both the maternal electrocardiogram (mECG and fECG simultaneously was modified by the manufacturer (Monica Healthcare, Nottingham, UK to provide an external TTL trigger signal from the detected fECG which could be used to trigger a standard 1.5 T MR (GE Healthcare, Milwaukee, WI, USA gating system with suitable attenuation. The MR scanner was tested by triggering rapidly during image acquisition at a typical fetal heart rate (123 beats per minute using a simulated fECG waveform fed into the gating system. Gated MR images were also acquired from volunteers who were attending for a repeat fetal Central Nervous System (CNS examination using an additional rapid cardiac imaging sequence triggered from the measured fECG. No adverse safety effects were encountered. This is the first time fECG gating has been used with MRI and opens up a range of new possibilities to study a developing foetus.

  3. ECG manifestations of left ventricular electrical remodeling.

    Science.gov (United States)

    Estes, E Harvey

    2012-01-01

    Research and thinking about the electrocardiographic manifestations of left ventricular hypertrophy has been constrained by a limited conceptual model of the process: heart disease produces chamber enlargement (increased mass), which in turn produces an altered electrocardiogram. The process is much more complex than can be represented in this simple model. A more robust and intricate model is proposed, in which heart (and vascular) disease causes structural changes, electrical changes, biochemical changes, and others, all of which interact to produce electrical remodeling of ventricular myocardium. This electrical remodeling results in a variety of ECG changes. All of these changes interact, leading to an altered clinical course, and to premature death. It is suggested that research, based on this model, can provide new clues to the processes involved, and improve the prediction of clinical outcomes. New directions in research, in recording equipment, and in organizational activities are suggested to test this new model, and to improve the usefulness of the electrocardiogram as a research and diagnostic tool.

  4. Low-cost compact ECG with graphic LCD and phonocardiogram system design.

    Science.gov (United States)

    Kara, Sadik; Kemaloğlu, Semra; Kirbaş, Samil

    2006-06-01

    Till today, many different ECG devices are made in developing countries. In this study, low cost, small size, portable LCD screen ECG device, and phonocardiograph were designed. With designed system, heart sounds that take synchronously with ECG signal are heard as sensitive. Improved system consist three units; Unit 1, ECG circuit, filter and amplifier structure. Unit 2, heart sound acquisition circuit. Unit 3, microcontroller, graphic LCD and ECG signal sending unit to computer. Our system can be used easily in different departments of the hospital, health institution and clinics, village clinic and also in houses because of its small size structure and other benefits. In this way, it is possible that to see ECG signal and hear heart sounds as synchronously and sensitively. In conclusion, heart sounds are heard on the part of both doctor and patient because sounds are given to environment with a tiny speaker. Thus, the patient knows and hears heart sounds him/herself and is acquainted by doctor about healthy condition.

  5. Nonlinear filtering in ECG Signal Enhancement

    Directory of Open Access Journals (Sweden)

    N. Siddiah

    2012-02-01

    Full Text Available High resolution ECG signals are needed in measuring cardiac abnormalities analysis. Generally baseline wander is one of the important artifact occurred in ECG signal extraction, this strongly affects the signal quality. In order to facilitate proper diagnosis these artifacts have to be removed. In this paper various non linear, non adaptive filtering techniques are presented for the removal of baseline wander removal from ECG signals. The performance characteristics of various filtering techniques are measured in terms of signal to noise ratio.

  6. 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).

  7. 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....

  8. 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.

  9. Comparison of Different ECG Signals on MATLAB

    Directory of Open Access Journals (Sweden)

    Rajan Chaudhary

    2013-03-01

    Full Text Available In this paper we discuss about biomedical engineering and then a brief description of ECG signal. We have generated a new method to compare different arrhythmic heart signals with normal sinus signals at MATLAB. This is making the comparison very easy. ECG is used to measure the rate and regularity of heartbeats, as well as the position and size of the chambers, the existence of any damage to the heart, and the effects of devices or drugs used to regulate the heart, such as a pacemaker. Uttermost ECGs are performed for diagnostic or research purposes on human hearts, but may also be performed on heart of animals, usually for diagnosis of heart abnormalities or research. Result obtained showing that Comparison of Normal (Sinus and Abnormal (arrhythmia ECG signal. Through this method we can compare any type of disordered signal of heart.

  10. Matching a wavelet to ECG signal.

    Science.gov (United States)

    Takla, George F; Nair, Bala G; Loparo, Kenneth A

    2006-01-01

    In this paper we develop an approach to synthesize a wavelet that matches the ECG signal. Matching a wavelet to a signal of interest has potential advantages in extracting signal features with greater accuracy, particularly when the signal is contaminated with noise. The approach that we have taken is based on the theoretical work done by Chapa and Rao. We have applied their technique to a noise-free ECG signal representing one cardiac cycle. Results indicate that a matched wavelet, that was able to capture the broad ECG features, could be obtained. Such a wavelet could be used to extract ECG features such as QRS complexes and P&T waves with greater accuracy.

  11. ECG Signal Feature Selection for Emotion Recognition

    Directory of Open Access Journals (Sweden)

    Lichen Xun

    2013-01-01

    Full Text Available This paper aims to study the selection of features based on ECG in emotion recognition. In the process of features selection, we start from existing feature selection algorithm, and pay special attention to some of the intuitive value on ECG waveform as well. Through the use of ANOVA and heuristic search, we picked out the different features to distinguish joy and pleasure these two emotions, then we combine this with pathological analysis of ECG signals by the view of the medical experts to discuss the logic corresponding relation between ECG waveform and emotion distinguish. Through experiment, using the method in this paper we only picked out five features and reached 92% of accuracy rate in the recognition of joy and pleasure.

  12. Classification of ECG Using Chaotic Models

    Directory of Open Access Journals (Sweden)

    Khandakar Mohammad Ishtiak

    2012-09-01

    Full Text Available Chaotic analysis has been shown to be useful in a variety of medical applications, particularly in cardiology. Chaotic parameters have shown potential in the identification of diseases, especially in the analysis of biomedical signals like electrocardiogram (ECG. In this work, underlying chaos in ECG signals has been analyzed using various non-linear techniques. First, the ECG signal is processed through a series of steps to extract the QRS complex. From this extracted feature, bit-to-bit interval (BBI and instantaneous heart rate (IHR have been calculated. Then some nonlinear parameters like standard deviation, and coefficient of variation and nonlinear techniques like central tendency measure (CTM, and phase space portrait have been determined from both the BBI and IHR. Standard database of MIT-BIH is used as the reference data where each ECG record contains 650000 samples. CTM is calculated for both BBI and IHR for each ECG record of the database. A much higher value of CTM for IHR is observed for eleven patients with normal beats with a mean of 0.7737 and SD of 0.0946. On the contrary, the CTM for IHR of eleven patients with abnormal rhythm shows low value with a mean of 0.0833 and SD 0.0748. CTM for BBI of the same eleven normal rhythm records also shows high values with a mean of 0.6172 and SD 0.1472. CTM for BBI of eleven abnormal rhythm records show low values with a mean of 0.0478 and SD 0.0308. Phase space portrait also demonstrates visible attractor with little dispersion for a healthy person’s ECG and a widely dispersed plot in 2-D plane for the ailing person’s ECG. These results indicate that ECG can be classified based on this chaotic modeling which works on the nonlinear dynamics of the system.

  13. Frequency-domain Analysis of ECG Signal

    Institute of Scientific and Technical Information of China (English)

    Tu Chengyuan; Zeng Yanjun; Li Shuxin

    2007-01-01

    A new simple approach to effectively detect QRS-T complexes in ECG curve is described, so as to easily get the P-wave (when AF does not happen)or the f-wave (when AF happens). By means of signal processing techniques such as the power spectrum function, the auto-correlation function and cross-correlation function,two kinds of ECG signal when AF does or does not happen were successively analyzed, showing the evident differences between them.

  14. An efficient unsupervised fetal QRS complex detection from abdominal maternal ECG.

    Science.gov (United States)

    Varanini, M; Tartarisco, G; Billeci, L; Macerata, A; Pioggia, G; Balocchi, R

    2014-08-01

    Non-invasive fetal heart rate is of great relevance in clinical practice to monitor fetal health state during pregnancy. To date, however, despite significant advances in the field of electrocardiography, the analysis of abdominal fetal ECG is considered a challenging problem for biomedical and signal processing communities. This is mainly due to the low signal-to-noise ratio of fetal ECG and difficulties in cancellation of maternal QRS complexes, motion and electromyographic artefacts. In this paper we present an efficient unsupervised algorithm for fetal QRS complex detection from abdominal multichannel signal recordings combining ICA and maternal ECG cancelling, which outperforms each single method. The signal is first pre-processed to remove impulsive artefacts, baseline wandering and power line interference. The following steps are then applied: maternal ECG extraction through independent component analysis (ICA); maternal QRS detection; maternal ECG cancelling through weighted singular value decomposition; enhancing of fetal ECG through ICA and fetal QRS detection. We participated in the Physionet/Computing in Cardiology Challenge 2013, obtaining the top official scores of the challenge (among 53 teams of participants) of event 1 and event 2 concerning fetal heart rate and fetal interbeat intervals estimation section. The developed algorithms are released as open-source on the Physionet website.

  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. 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. A portable ECG monitoring device with Bluetooth and Holter capabilities for telemedicine applications.

    Science.gov (United States)

    Lucani, Daniel; Cataldo, Giancarlos; Cruz, Julio; Villegas, Guillermo; Wong, Sara

    2006-01-01

    A prototype of a portable ECG-monitoring device has been developed for clinical and non-clinical environments as part of a telemedicine system to provide remote and continuous surveillance of patients. The device can acquire, store and/or transmit ECG signals to computer-based platforms or specially configured access points (AP) with Intranet/Internet capabilities in order to reach remote monitoring stations. Acquired data can be stored in a flash memory card in FAT16 format for later recovery, or transmitted via Bluetooth or USB to a local station or AP. This data acquisition module (DAM) operates in two modes: Holter and on-line transmission.

  18. Image quality, radiation dose, and diagnostic accuracy of prospectively ECG-triggered high-pitch coronary CT angiography at 70 kVp in a clinical setting: comparison with invasive coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Long Jiang; Qi, Li; Zhou, Chang Sheng; Zhao, Yan E.; Li, Xie; Lu, Guang Ming [Jinling Hospital, Medical School of Nanjing University, Department of Medical Imaging, Nanjing, Jiangsu (China); Wang, Yining; Cao, Jian; Jin, Zhengyu [Peking Union Medical College Hospital, Department of Radiology, Beijing (China); Schoepf, U.J. [Jinling Hospital, Medical School of Nanjing University, Department of Medical Imaging, Nanjing, Jiangsu (China); Medical University of South Carolina, Division of Cardiovascular Imaging, Charleston, SC (United States); Meinel, Felix G. [Medical University of South Carolina, Division of Cardiovascular Imaging, Charleston, SC (United States); Ludwig-Maximilians-University Hospital, Institute for Clinical Radiology, Munich (Germany); Bayer, Richard R. [Medical University of South Carolina, Division of Cardiovascular Imaging, Charleston, SC (United States); Gong, Jian Bin [Jinling Hospital, Medical School of Nanjing University, Department of Cardiology, Nanjing, Jiangsu (China)

    2016-03-15

    To investigate image quality, radiation dose, and diagnostic performance of prospectively ECG-triggered high-pitch coronary CT angiography (CCTA) at 70 kVp compared to invasive coronary angiography (ICA) as reference standard. Forty-three patients underwent prospectively ECG-triggered high-pitch CCTA at 70 kVp using 30 cc (11 g iodine) contrast medium and ICA. Subjective and objective image quality was evaluated for each CCTA study. CCTA performance for diagnosing ≥50 % stenosis was assessed. Results were stratified according to heart rate (HR), body mass index (BMI), Agatston score, and image quality. At CCTA, 94.3 % (500/530) of coronary segments were of diagnostic quality. Using ICA as reference standard, sensitivity and accuracy were 100 % and 93.0 % on a per-patient basis. Per-vessel and per-segment performances were 92.2 % and 89.5 %; 79.5 % and 88.3 %, respectively. No differences were found in diagnostic accuracy between different HR, BMI, and calcification subgroups (all P > 0.05) on a per-patient basis. However, low image quality reduced diagnostic accuracy on a per-patient, per-vessel and per-segment basis (all P < 0.05). The mean effective radiation dose was 0.2 ± 0.0 mSv. Our presented protocol results in an effective radiation dose of 0.2 mSv and high diagnostic accuracy for stenosis detection in a selected, non-obese population. (orig.)

  19. QRS DETECTION OF ECG - A STATISTICAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    I.S. Siva Rao

    2015-03-01

    Full Text Available Electrocardiogram (ECG is a graphical representation generated by heart muscle. ECG plays an important role in diagnosis and monitoring of heart’s condition. The real time analyzer based on filtering, beat recognition, clustering, classification of signal with maximum few seconds delay can be done to recognize the life threatening arrhythmia. ECG signal examines and study of anatomic and physiologic facets of the entire cardiac muscle. The inceptive task for proficient scrutiny is the expulsion of noise. It is attained by the use of wavelet transform analysis. Wavelets yield temporal and spectral information concurrently and offer stretchability with a possibility of wavelet functions of different properties. This paper is concerned with the extraction of QRS complexes of ECG signals using Discrete Wavelet Transform based algorithms aided with MATLAB. By removing the inconsistent wavelet transform coefficient, denoising is done in ECG signal. In continuation, QRS complexes are identified and in which each peak can be utilized to discover the peak of separate waves like P and T with their derivatives. Here we put forth a new combinatory algorithm builded on using Pan-Tompkins' method and multi-wavelet transform.

  20. Designing for reliable textile neonatal ECG monitoring using multi-sensor recordings.

    Science.gov (United States)

    Bouwstra, S; Chen, W; Oetomo, S Bambang; Feijs, L M G; Cluitmans, P J M

    2011-01-01

    When designing an ECG monitoring system embedded with textile electrodes for comfort, it is challenging to ensure reliable monitoring, because textile electrodes suffer from motion artifacts and incidental poor signal quality. For the design of a comfortable monitoring system for prematurely born babies in the Neonatal Intensive Care Unit (NICU), we propose the concepts of 'diversity measurement' and 'context awareness' to improve reliability. Clinical multi-modal sensor data was collected in the NICU with the Smart Jacket connected to a state-of-the-art amplifier. We found that the ECG signals quality varied among sensors and varied over time, and found correlations between ECG signal, acceleration data, and context, which supports the feasibility of the concepts. Our explorative system level approach has lead to design parameters and meta-insights into the role of clinical validation in the design process.

  1. Robust human identification using ecg: eigenpulse revisited

    Science.gov (United States)

    Jang, Daniel; Wendelken, Suzanne; Irvine, John M.

    2010-04-01

    Biometrics, such as fingerprint, iris scan, and face recognition, offer methods for identifying individuals based on a unique physiological measurement. Recent studies indicate that a person's electrocardiogram (ECG) may also provide a unique biometric signature. Several methods for processing ECG data have appeared in the literature and most approaches rest on an initial detection and segmentation of the heartbeats. Various sources of noise, such as sensor noise, poor sensor placement, or muscle movements, can degrade the ECG signal and introduce errors into the heartbeat segmentation. This paper presents a screening technique for assessing the quality of each segmented heartbeat. Using this technique, a higher quality signal can be extracted to support the identification task. We demonstrate the benefits of this quality screening using a principal component technique known as eigenpulse. The analysis demonstrated the improvement in performance attributable to the quality screening.

  2. 心电门控CTA评价急性主动脉夹层的临床应用研究%Clinical Application of ECG Gated CTA in Evaluation of Acute Aortic Dissection

    Institute of Scientific and Technical Information of China (English)

    陈凤丽; 刘挨师

    2016-01-01

    Objective: In this study, we would compare to the routine aorta CTA and ECG gated aorta CTA image quality, in order to know the advantage of ECG gated aorta CTA in evaluation of aortic dissection. Methods:Through the imaging system retrospectively selected 62 patients who underwent aorta CTA from 2013 January to 2016 March, divided into two groups. Group A underwent triple rule out scanning (13 cases), group B underwent aortic CTA (49 cases). Evaluation of aortic image quality and assessment of various indexes of aortic dissection. The measurement data were compared by two independent samplesttest, and count data were compared using chi-square test. A(P0.05). Conclusions: Applying the ECG gated aortic CTA compared with the conventional spiral aorta CTA, it could clearly displaythe index of aortic dissection, evaluate prognosis ofaortic dissection, guide the therapy and formulate operation /endovascular treatment plan.%目的:本研究通过主动脉CTA与胸痛三联排查扫描(心电门控)CTA主动脉图像质量的比较,明确施加心电门控的 CTA 在临床选择与评价主动脉夹层治疗方案中的价值。方法:通过影像数据存储与传输系统(PACS)回顾性选取2013年1月至2016年3月间行胸痛三联排查与主动脉CTA 的患者62例,分为两组,A 组行胸痛三联排查扫描(13例),B 组行主动脉 CTA(49例)。评价主动脉图像质量与主动脉夹层各项指标可评估性。计量资料比较采用两独立样本t检验,计数资料比较采用χ2检验。P0.05)。结论:施加心电门控的主动脉CTA较常规螺旋扫描主动脉CTA可以更加清晰地显示主动脉夹层各项指标,在进行疾病预后评估、指导治疗方案与制定手术/血管内治疗计划中具有一定作用。

  3. Changes in ECG features and clinical prognosis of ventricular electrical storm in patients with left ventricular hypertrophy and acute myocardial infarction%左心室肥厚并急性心肌梗死室性电风暴心电图对预后的影响

    Institute of Scientific and Technical Information of China (English)

    于文江; 王为民

    2009-01-01

    目的 探讨沿海居民高血压性左室肥厚(left ventricular hypertrophy,LNH)并急性心肌梗死(acute myocardial infarction,AMI)后心电图特征性改变,评估室性电风暴与临床预后危险分层.方法 选择急诊住院有高皿压性LVH并AMI室性电风暴(室速或室颤)317例(Ⅱ组),另选无高血压性LVH室性电风暴AMI 109例(Ⅰ组)进行心电图检查和持续心电监护,分析心电图特征与临床高危特点.结果 室性电风暴组以高血压LVH并AMI患者心电图指标心房终末电势异常、∑ST段抬高振幅、ST段抬高导联数、QTc间期延长、对应导联ST段振幅下移等特征,梗死部位以前壁或复合前壁,并以左前降支合并回旋支或/和右冠脉完全闭塞多支病变为主,与Ⅰ组比较差异有统计学意义(P<0.05或P<0.01),临床并发泵衰竭、AMI扩展、住院病死率、室性电风暴AMI发病后6 h内发生率明显增多(P<0.01).结论 高血压性LVH并AMI室性电风暴患者,心电图多项指标异常对临床预后有预测作用.%Objective To investigate changes in ECG feature and clinical prognosis of ventricular electrical storm (VES) in patients with left ventricular hypertrophy (LVH) and acute myocardial infarction (AMI). Methods Three hundred and seventeen cases of left ventricular hypertrophy induced by hypertension and combined with AMI (Group Ⅱ) from emergency inpatients, and another 109 patients without LVH induced by hypertension and accompanied with AMI (Group Ⅰ) were chosen to have sustained ECG monitoring, analyze ECG features and clinical high risks. Results Clinical features, such as abnormality in PTFvl,ΣST segment elevation amplitude, ST segment elevation leads, ST segment reduction amplitude leads, QTc interval prolongation could be noted in the VES group. Infarction could be seen at sites of anterior and complex anterior walls, and dominant clinical signs were mainly at left descending branches accompanied by circumflex arteries and

  4. A Mixed Approach Of Automated ECG Analysis

    Science.gov (United States)

    De, A. K.; Das, J.; Majumder, D. Dutta

    1982-11-01

    ECG is one of the non-invasive and risk-free technique for collecting data about the functional state of the heart. However, all these data-processing techniques can be classified into two basically different approaches -- the first and second generation ECG computer program. Not the opposition, but simbiosis of these two approaches will lead to systems with the highest accuracy. In our paper we are going to describe a mixed approach which will show higher accuracy with lesser amount of computational work. Key Words : Primary features, Patients' parameter matrix, Screening, Logical comparison technique, Multivariate statistical analysis, Mixed approach.

  5. Principal Component Analysis in ECG Signal Processing

    Directory of Open Access Journals (Sweden)

    Andreas Bollmann

    2007-01-01

    Full Text Available This paper reviews the current status of principal component analysis in the area of ECG signal processing. The fundamentals of PCA are briefly described and the relationship between PCA and Karhunen-Loève transform is explained. Aspects on PCA related to data with temporal and spatial correlations are considered as adaptive estimation of principal components is. Several ECG applications are reviewed where PCA techniques have been successfully employed, including data compression, ST-T segment analysis for the detection of myocardial ischemia and abnormalities in ventricular repolarization, extraction of atrial fibrillatory waves for detailed characterization of atrial fibrillation, and analysis of body surface potential maps.

  6. ECG-based gating in ultra high field cardiovascular magnetic resonance using an independent component analysis approach

    OpenAIRE

    Krug, Johannes W; Rose, Georg; Clifford, Gari D.; Oster, Julien

    2013-01-01

    Background In Cardiovascular Magnetic Resonance (CMR), the synchronization of image acquisition with heart motion is performed in clinical practice by processing the electrocardiogram (ECG). The ECG-based synchronization is well established for MR scanners with magnetic fields up to 3 T. However, this technique is prone to errors in ultra high field environments, e.g. in 7 T MR scanners as used in research applications. The high magnetic fields cause severe magnetohydrodynamic (MHD) effects w...

  7. A Case of Isolated Left Ventricular Noncompaction with Basal ECG-Tracing Strongly Suggestive for Type-2 Brugada Syndrome

    Directory of Open Access Journals (Sweden)

    Maria Banci

    2011-01-01

    Full Text Available Isolated left ventricular noncompaction (ILVNC is a cardiomyopathy caused by intrauterine arrest of compaction of the myocardial fibres and meshwork, an important process in myocardial development. ILVNC is clinically accompanied by depressed ventricular function, arrhythmias, and systemic embolization. We reported a case of ILVNC with basal ECG-tracing strongly suggestive for type-2 Brugada syndrome (BrS. Up to now, this is the first report investigating the association between ILVNC and this particular ECG pattern.

  8. ECG-6511故障维修%The troublity repair of ECG-6511

    Institute of Scientific and Technical Information of China (English)

    张燕

    2001-01-01

    @@ 日本光电ECG-6511型心电图机是在ECG-6151型心电图机的基础上设计生产的一种便携式单导心电图机.它操作简单、携带方便,被广泛应用.我院的心电图机,大部分都是ECG-6511型.现把它的几种故障维修经验介绍给大家,以供参考:

  9. [Implementation of ECG Monitoring System Based on Internet of Things].

    Science.gov (United States)

    Lu, Liangliang; Chen, Minya

    2015-11-01

    In order to expand the capabilities of hospital's traditional ECG device and enhance medical staff's work efficiency, an ECG monitoring system based on internet of things is introduced. The system can monitor ECG signals in real time and analyze data using ECG sensor, PDA, Web servers, which embeds C language, Android systems, .NET, wireless network and other technologies. After experiments, it can be showed that the system has high reliability and stability and can bring the convenience to medical staffs.

  10. A comparison of photoplethysmography and ECG recording to analyse heart rate variability in healthy subjects.

    Science.gov (United States)

    Lu, G; Yang, F; Taylor, J A; Stein, J F

    2009-01-01

    Measures of heart rate variability (HRV) are widely used to assess autonomic nervous system (ANS) function. The signal from which they are derived requires accurate determination of the interval between successive heartbeats; it can be recorded via electrocardiography (ECG), which is both non-invasive and widely available. However, methodological problems inherent in the recording and analysis of ECG traces have motivated a search for alternatives. Photoplethysmography (PPG) constitutes another means of determining the timing of cardiac cycles via continuous monitoring of changes in blood volume in a portion of the peripheral microvasculature. This technique measures pulse waveforms, which in some instances may prove a practical basis for HRV analysis. We investigated the feasibility of using earlobe PPG to analyse HRV by applying the same analytic process to PPG and ECG recordings made simultaneously. Comparison of 5-minute recordings demonstrated a very high degree of correlation in the temporal and frequency domains and in nonlinear dynamic analyses between HRV measures derived from PPG and ECG. Our results confirm that PPG provides accurate interpulse intervals from which HRV measures can be accurately derived in healthy subjects under ideal conditions, suggesting this technique may prove a practical alternative to ECG for HRV analysis. This finding is of particular relevance to the care of patients suffering from peripheral hyperkinesia or tremor, which make fingertip PPG recording impractical, and following clinical interventions known to introduce electrical artefacts into the electrocardiogram.

  11. Modeling left and right atrial contributions to the ECG: A dipole-current source approach.

    Science.gov (United States)

    Jacquemet, Vincent

    2015-10-01

    This paper presents the mathematical formulation, the numerical validation and several illustrations of a forward-modeling approach based on dipole-current sources to compute the contribution of a part of the heart to the electrocardiogram (ECG). Clinically relevant applications include identifying in the ECG the contributions from the right and the left atrium. In a Courtemanche-based monodomain computer model of the atria and torso, 1000 dipoles distributed throughout the atrial mid-myocardium are found to be sufficient to reproduce body surface potential maps with a relative error approach enables fast offline computation of the ECG contribution of any anatomical part of the atria by applying the principle of superposition to the dipole sources. In the presence of a right-left activation delay (sinus rhythm), pulmonary vein isolation (sinus rhythm) or left-right differences in refractory period (atrial fibrillation), the decomposition of the ECG is shown to help interpret ECG morphology in relation to the atrial substrate. These tools provide a theoretical basis for a deeper understanding of the genesis of the P wave or fibrillatory waves in normal and pathological cases.

  12. A computer based wireless system for online acquisition, monitoring and digital processing of ECG waveforms.

    Science.gov (United States)

    Bansal, Dipali; Khan, Munna; Salhan, Ashok K

    2009-04-01

    Various ECG instruments have addressed a wide variety of clinical and technical issues. However, there is still scope for improvement in them particularly in the area of their susceptibility to noise, lack of universal connectivity and off-line processing. A prototype system has been developed that caters to these limitations. It includes an analog system and a FM transceiver pair interfaced through sound port of the computer. The real time acquired data is viewed and filtered using MATLAB software. The ECG system described captures the bio-signal faithfully in real time wireless mode with minimum noise and has universal connectivity.

  13. The 4th Report of the Working Group on ECG diagnosis of Left Ventricular Hypertrophy

    DEFF Research Database (Denmark)

    Bacharova, Ljuba; Estes, Harvey E; Schocken, Douglas D

    2016-01-01

    The 4th Report provides a brief review of publications focused on the electrocardiographic diagnosis of left ventricular hypertrophy published during the period of 2010 to 2016 by the members of the Working Group on ECG diagnosis of Left Ventricular Hypertrophy. The Working Group recommended...... that ECG research and clinical attention be redirected from the estimation of LVM to the identification of electrical remodeling, to better understanding the sequence of events connecting electrical remodeling to outcomes. The need for a re-definition of terms and for a new paradigm is also stressed....

  14. 21 CFR 892.1970 - Radiographic ECG/respirator synchronizer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiographic ECG/respirator synchronizer. 892.1970... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1970 Radiographic ECG/respirator synchronizer. (a) Identification. A radiographic ECG/respirator synchronizer is a device intended to be used...

  15. Development of standard test methods for evaluating defibrillation recovery characteristics of disposable ECG electrodes.

    Science.gov (United States)

    Schoenberg, A A; Booth, H E; Lyon, P C

    1979-01-01

    A clinically relevant test for the measurement of defibrillation overload recovery of prefilled disposable ECG electrodes was developed and is proposed for use in an ECG electrode standard under development by AAMI. Defibrillation overload voltages and currents, as well as electrode polarization recovery voltages, were first measured in animal tests on 12 types of electrodes to allow correlation with various bench tests using a capacitor discharge at 10, 200, or 1000 V. Current overloads absorbed by the electrodes under worst conditions in animal tests were in the range of 2 percent of the defibrillation current flowing through the chest. These overloads were absorbed by most Ag-AgCl electrodes without excessive polarization. However, stainless steel, brass, and tin electrodes tended to polarize to levels that would saturate many ECG monitors. A standard bench test using a 200-V 10-muF capacitor was recommended for inclusion in the AAMI standard to determine whether electrodes are acceptable for use during defibrillation.

  16. An ECG storage and retrieval system embedded in client server HIS utilizing object-oriented DB.

    Science.gov (United States)

    Wang, C; Ohe, K; Sakurai, T; Nagase, T; Kaihara, S

    1996-02-01

    In the University of Tokyo Hospital, the improved client server HIS has been applied to clinical practice and physicians can order prescription, laboratory examination, ECG examination and radiographic examination, etc. directly by themselves and read results of these examinations, except medical signal waves, schema and image, on UNIX workstations. Recently, we designed and developed an ECG storage and retrieval system embedded in the client server HIS utilizing object-oriented database to take the first step in dealing with digitized signal, schema and image data and show waves, graphics, and images directly to physicians by the client server HIS. The system was developed based on object-oriented analysis and design, and implemented with object-oriented database management system (OODMS) and C++ programming language. In this paper, we describe the ECG data model, functions of the storage and retrieval system, features of user interface and the result of its implementation in the HIS.

  17. Powerline interference reduction in ECG signals using empirical wavelet transform and adaptive filtering.

    Science.gov (United States)

    Singh, Omkar; Sunkaria, Ramesh Kumar

    2015-01-01

    Separating an information-bearing signal from the background noise is a general problem in signal processing. In a clinical environment during acquisition of an electrocardiogram (ECG) signal, The ECG signal is corrupted by various noise sources such as powerline interference (PLI), baseline wander and muscle artifacts. This paper presents novel methods for reduction of powerline interference in ECG signals using empirical wavelet transform (EWT) and adaptive filtering. The proposed methods are compared with the empirical mode decomposition (EMD) based PLI cancellation methods. A total of six methods for PLI reduction based on EMD and EWT are analysed and their results are presented in this paper. The EWT-based de-noising methods have less computational complexity and are more efficient as compared with the EMD-based de-noising methods.

  18. Comparative analysis of clinical effect of cardiac B ultrasound and ECG in the diagnosis of hypertensive heart disease%心脏超声与心电图在高血压性心脏病诊断中的临床效果对比分析

    Institute of Scientific and Technical Information of China (English)

    张颖凤

    2015-01-01

    Objective:To compare the clinical effect of heart B ultrasound and ECG in the diagnosis of hypertensive heart disease. Methods:Retrospective analysis of the clinical data of 53 patients with hypertensive heart disease.Results:The left ventricular hypertrophy in patients with B ultrasound examination,the expansion of the heart,left atrial enlargement detection rate was significantly higher than the ECG of patients.Conclusion:Visible heart B ultrasound is more sensitive to changes in the heart patients,is a noninvasive,effective detection method.%目的:比较心脏超声与心电图在高血压性心脏病诊断中的临床效果。方法:回顾性分析53例高血压性心脏病患者的临床资料,对其进行心脏超声检查及心电图检查,比较两种检查方法的检查结果。结果:心脏超声检查患者左室肥厚、左室扩大、左房增大检出率显著高于心电图检查患者,差异具统计学意义(P<0.05)。结论:针对高血压性心脏病患者,心脏超声检测的检出率显著高于心电图检查,可见心脏超声对患者的心脏变化比较敏感,是一种无创、有效的检测方法。

  19. 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.

  20. The effect of ECG interference on pattern-recognition-based myoelectric control for targeted muscle reinnervated patients.

    Science.gov (United States)

    Hargrove, Levi; Zhou, Ping; Englehart, Kevin; Kuiken, Todd A

    2009-09-01

    Targeted muscle reinnervation has been introduced as an effective neural machine interface. In the case of a shoulder disarticulation patient, an effective site for a nerve transfer involves the pectoralis muscles, as these perform little useful function with a missing limb. Consequently, the myoelectric signals measured from the reinnervated muscles may be corrupted by a large amount of ECG interference. This paper investigates the effect of ECG upon the accuracy of a pattern-classification-based scheme for myoelectric control of powered upper limb prostheses. The results suggest that ECG interference, at levels typically encountered in a clinical measurement, has little effect upon classification accuracy, but can affect the estimate of myoelectric activity used to convey the velocity of motion (commonly referred to as proportional control). High-pass filtering at approximately 100 Hz appears to effectively mitigate the effect of ECG interference.

  1. The Safety Assessment and Clinical Countermeasure of the Elderly Hypertensive Patients with ECG Monitoring Dental Treatment%老年高血压患者监护治牙安全评估及临床对策

    Institute of Scientific and Technical Information of China (English)

    郑立娟; 汤晨; 赵旭

    2014-01-01

    观察在心电监护下局麻治疗急性牙髓炎,对老年高血压患者的影响,为其安全治疗提供参考。监测522名老年高血压患者在急性牙髓炎治疗前后及过程中的血压、心率等变化,将测量结果进行分析。患者血压在麻醉即刻及术中比治疗前明显升高(P<0.05),其中收缩压较舒张压变化更为明显。心率在麻醉即刻及治疗中均明显高于治疗前(P<0.05)。病情稳定的老年高血压患者可在心电监护下治牙,Ⅱ、Ⅲ级高血压,可据情况,静脉给药控制性降压,避免高血压危象的发生,严格掌握老年高血压患者治牙适应症,可明显降低治疗中并发症发生的风险,可提高老年高血压患者治牙的安全系数。%ECG monitoring was observed under local anesthesia treatment of acute pulpitis, the impact on elderly hypertensive patients, and to provide for their safe treatment. Monitoring 522 elderly hypertensive patients’ blood pressure, heart rate and other changes in the treatment of acute pulpitis before and during, the measurement results were analyzed. Patient's blood pressure in anesthetized instantly and intraoperative significantly higher than before treatment (P<0.05), the change of systolic blood pressure than diastolic blood pressure was more obvious (P<0.05). In a stable condition of elderly patients with high blood pressure can be dental treatment under ECG monitor, II and III high blood pressure, can according to the situation, intravenous dosing control step-down, avoid the happening of hypertensive crisis, strictly grasp the indications in elderly patients with hypertension treated teeth, can obviously reduce the risk of complications in the treatment, can improve the elderly cardiovascular disease cure tooth safety coefficient.

  2. Repair of Common Trouble ECG Monitor%心电监护仪常见故障维修研究

    Institute of Scientific and Technical Information of China (English)

    杜永峰

    2015-01-01

    心电监护仪属于一项临床设备,专门用于无创监测,医务人员通过心电监护仪,观察病人的心电图、心率等,发挥计量的功能。心电监护仪的精密性强,其可在同一时间,监护病人的多项生理参数,临床中,必须确保心电监护仪处于正常的状态,因此,本文以心电监护仪为例,分析常见的故障及维修策略。%the ECG monitor belongs to a clinical equipment, speciifcaly for noninvasive monitoring. The medical personnel through the ECG monitor, observe the patient's ECG, heart rate measurement, play function. ECG monitor precision, which can at the same time, patient monitoring of multiple physiological parameters, clinical must ensure that ECG monitor in the normal state. Therefore, this paper to ECG monitor for example. Analysis common faults and maintenance strategy.

  3. The Development of a Portable ECG Monitor Based on DSP

    Science.gov (United States)

    Nan, CHI Jian; Tao, YAN Yan; Meng Chen, LIU; Li, YANG

    With the advent of global information, researches of Smart Home system are in the ascendant, the ECG real-time detection, and wireless transmission of ECG become more useful. In order to achieve the purpose we developed a portable ECG monitor which achieves the purpose of cardiac disease remote monitoring, and will be used in the physical and psychological disease surveillance in smart home system, we developed this portable ECG Monitor, based on the analysis of existing ECG Monitor, using TMS320F2812 as the core controller, which complete the signal collection, storage, processing, waveform display and transmission.

  4. Sparse Matrix for ECG Identification with Two-Lead Features

    Directory of Open Access Journals (Sweden)

    Kuo-Kun Tseng

    2015-01-01

    Full Text Available Electrocardiograph (ECG human identification has the potential to improve biometric security. However, improvements in ECG identification and feature extraction are required. Previous work has focused on single lead ECG signals. Our work proposes a new algorithm for human identification by mapping two-lead ECG signals onto a two-dimensional matrix then employing a sparse matrix method to process the matrix. And that is the first application of sparse matrix techniques for ECG identification. Moreover, the results of our experiments demonstrate the benefits of our approach over existing methods.

  5. Computationally efficient sub-band coding of ECG signals.

    Science.gov (United States)

    Husøy, J H; Gjerde, T

    1996-03-01

    A data compression technique is presented for the compression of discrete time electrocardiogram (ECG) signals. The compression system is based on sub-band coding, a technique traditionally used for compressing speech and images. The sub-band coder employs quadrature mirror filter banks (QMF) with up to 32 critically sampled sub-bands. Both finite impulse response (FIR) and the more computationally efficient infinite impulse response (IIR) filter banks are considered as candidates in a complete ECG coding system. The sub-bands are threshold, quantized using uniform quantizers and run-length coded. The output of the run-length coder is further compressed by a Huffman coder. Extensive simulations indicate that 16 sub-bands are a suitable choice for this application. Furthermore, IIR filter banks are preferable due to their superiority in terms of computational efficiency. We conclude that the present scheme, which is suitable for real time implementation on a PC, can provide compression ratios between 5 and 15 without loss of clinical information.

  6. Rapid assessment of ECG for hypokalemia%心电图对低钾血症的快速评价作用

    Institute of Scientific and Technical Information of China (English)

    周军荣; 王晋丽

    2011-01-01

    目的 了解心电图(ECG)对低钾血症的快速评价作用,应用于临床急诊治疗低钾血症.方法 选取有低血钾ECG特征表现的患者130例,对照同步12导联ECG并同时查阅当时的血清K+,观察不同血清K+患者的ECG特征并进行分析.结果 130例有低血钾ECG表现患者中115例血清K+降低,ECG对低钾血症的诊断敏感度为88.5%.结论 ECG可作为快速筛查低钾血症的简捷方法 之一,ECG的特征表现对低钾血症有较高的预测价值,对临床急诊治疗低钾血症有快速、及时的指导意义.%Objective To understand the rapid assessment of electrocardiography ( ECG) for hypokalemia and the application of ECG for hypokalemia therapy in clinical emergency. Methods 130patients with low serum potassium under ECG were selected, their synchronous 12 leads ECG were analyzed and the concentration of serum potassiuM was observed at the same time, and the characteristics of ECG at the different concentration of serum potassium were analyzed. Results There are 115 cases of hypokalemia in 130 patients with low serum potassium under ECG. The diagnostic sensitivity of ECG for hypokalemia was 88.5%. Conclusion ECG could Be one of the effective methods in screening hypokalemia rapidly, and has great predictive value for hypokalemia. Also, ECG may instruct the hypokalemia therapy in clinical emergency timely.

  7. STUDY OF ECG CHANGES IN SMOKERS

    Directory of Open Access Journals (Sweden)

    Syamala Devi

    2014-10-01

    Full Text Available This study is intended to evaluate the changes in Electrocardiogram (ECG in apparently healthy adult male smokers. This cross-sectional study covers 40 smokers, who smoked on an average 10 cigarettes per day for at least 5 years, and 40 non-smokers to find out the possible risk factors for cardiovascular disorders. This study was conducted during April 2011 to April 2012 in the Department of Physiology of Andhra Medical College, on subjects whose age ranged from 20 to 60 years. The ECG results were evaluated for different parameters like heart rate, P-wave, P-R interval, QRS complex, QT interval, and T-wave. The results were analyzed using student’s t-test. The probability (p value was calculated. The analysis showed that QRS and QT interval were shortened and that the QTc interval was widened in the smokers, although the values did not show any statistical significance. From the statistical analysis of the results obtained in the present study and their comparison with those of published reports, it appears that smoking 10 cigarettes per day for 5 Years does not cause major change in ECG wave forms.

  8. Prospectively ECG Gated CT pulmonary angiography versus helical ungated CT pulmonary angiography: Impact on cardiac related motion artifacts and patient radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    Shuman, William P., E-mail: wshuman@u.washington.edu [Department of Radiology, 1959 NE Pacific Street, Box 357115, Seattle, WA 98195 (United States); Leipsic, Jonathon A., E-mail: JLeipsic@providencehealth.bc.ca [University of British Columbia and St. Paul' s Hospital, Department of Radiology, 1081 Burrard Street, Vancouver, BC, V6Z1Y6 (Canada); Busey, Janet M., E-mail: jbonny@u.washington.edu [Department of Radiology, 1959 NE Pacific Street, Box 357115, Seattle, WA 98195 (United States); Green, Douglas E., E-mail: dougreen@uw.edu [Department of Radiology, 1959 NE Pacific Street, Box 357115, Seattle, WA 98195 (United States); Pipavath, Sudhakar N., E-mail: snjp@u.wwashington.edu [Department of Radiology, 1959 NE Pacific Street, Box 357115, Seattle, WA 98195 (United States); Hague, Cameron J., E-mail: cjhague@interchange.ubc.ca [University of British Columbia and St. Paul' s Hospital, Department of Radiology, 1081 Burrard Street, Vancouver, BC, V6Z1Y6 (Canada); Koprowicz, Kent M., E-mail: kentk@u.washington.edu [Department of Radiology, 1959 NE Pacific Street, Box 357115, Seattle, WA 98195 (United States)

    2012-09-15

    Objective: To compare prospectively ECG gated CT pulmonary angiography (CTPA) with routine helical ungated CTPA for cardiac related motion artifacts and patient radiation dose. Subjects and methods: Twenty patients with signs and symptoms suspicious for pulmonary embolism and who had a heart rate below 85 were scanned with prospectively ECG gated CTPA. These gated exams were matched for several clinical parameters to exams from twenty similar clinical patients scanned with routine ungated helical CTPA. Three blinded independent reviewers subjectively evaluated all exams for overall pulmonary artery enhancement and for several cardiac motion related artifacts, including vessel blurring, intravascular shading, and double line. Reviewers also measured pulmonary artery intravascular density and image noise. Patient radiation dose for each technique was compared. Fourteen clinical prospectively ECG gated CTPA exams from a second institution were evaluated for the same parameters. Results: Prospectively ECG gated CTPA resulted in significantly decreased motion-related image artifact scores in lung segments adjacent to the heart compared to ungated CTPA. Measured image noise was not significantly different between the two types of CTPA exams. Effective dose was 28% less for prospectively ECG gated CTPA (4.9 mSv versus 6.8 mSv, p = 0.02). Similar results were found in the prospectively ECG gated exams from the second institution. Conclusion: Compared to routine helical ungated CTPA, prospectively ECG gated CTPA may result in less cardiac related motion artifact in lung segments adjacent to the heart and significantly less patient radiation dose.

  9. 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

    2015-01-01

    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. PMID:26307995

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

    Directory of Open Access Journals (Sweden)

    Kuo-Kun Tseng

    2015-08-01

    Full Text Available 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.

  11. 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.

  12. Electrocardiogram (ECG) pattern modeling and recognition via deterministic learning

    Institute of Scientific and Technical Information of China (English)

    Xunde DONG; Cong WANG; Junmin HU; Shanxing OU

    2014-01-01

    A method for electrocardiogram (ECG) pattern modeling and recognition via deterministic learning theory is presented in this paper. Instead of recognizing ECG signals beat-to-beat, each ECG signal which contains a number of heartbeats is recognized. The method is based entirely on the temporal features (i.e., the dynamics) of ECG patterns, which contains complete information of ECG patterns. A dynamical model is employed to demonstrate the method, which is capable of generating synthetic ECG signals. Based on the dynamical model, the method is shown in the following two phases:the identification (training) phase and the recognition (test) phase. In the identification phase, the dynamics of ECG patterns is accurately modeled and expressed as constant RBF neural weights through the deterministic learning. In the recognition phase, the modeling results are used for ECG pattern recognition. The main feature of the proposed method is that the dynamics of ECG patterns is accurately modeled and is used for ECG pattern recognition. Experimental studies using the Physikalisch-Technische Bundesanstalt (PTB) database are included to demonstrate the effectiveness of the approach.

  13. A model-based approach to human identification using ECG

    Science.gov (United States)

    Homer, Mark; Irvine, John M.; Wendelken, Suzanne

    2009-05-01

    Biometrics, such as fingerprint, iris scan, and face recognition, offer methods for identifying individuals based on a unique physiological measurement. Recent studies indicate that a person's electrocardiogram (ECG) may also provide a unique biometric signature. Current techniques for identification using ECG rely on empirical methods for extracting features from the ECG signal. This paper presents an alternative approach based on a time-domain model of the ECG trace. Because Auto-Regressive Integrated Moving Average (ARIMA) models form a rich class of descriptors for representing the structure of periodic time series data, they are well-suited to characterizing the ECG signal. We present a method for modeling the ECG, extracting features from the model representation, and identifying individuals using these features.

  14. Compressed domain ECG biometric with two-lead features

    Science.gov (United States)

    Lee, Wan-Jou; Chang, Wen-Whei

    2016-07-01

    This study presents a new method to combine ECG biometrics with data compression within a common JPEG2000 framework. We target the two-lead ECG configuration that is routinely used in long-term heart monitoring. Incorporation of compressed-domain biometric techniques enables faster person identification as it by-passes the full decompression. Experiments on public ECG databases demonstrate the validity of the proposed method for biometric identification with high accuracies on both healthy and diseased subjects.

  15. A STUDY OF CORRELATION BETWEEN THE ECG CHANGES WITH THE DURATION AND SEVERITY OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE

    Directory of Open Access Journals (Sweden)

    Jitendra

    2014-02-01

    Full Text Available INTRODUCTION : Chronic obstructive pulmonary disease (COPD is a major cause of morbidity and mortality in India especially in rural areas. COPD is the 5th leading cause of death worldwide. COPD causes hypoxia in lungs triggering the pulmonary vasoconstriction which lead s to increase in pulmonary vascular resistance finally involving the heart and causes right sided cardiac complications which can be evidenced by Electrocardiography (ECG. Therefore , the present study was conducted to evaluate the diagnostic values of ECG changes among COPD patients. MATERIAL AND METHODS : This was a cross - sectional study done in the Medicine department of Chirayu Medical College and Hospital , Bhopal during the period from January 2012 to June 2012. 60 cases of COPD were selected for study. The diagnosis of COPD is based upon the clinical history , clinical examination , X - ray chest and Pulmonary Function Test (PFT. ECG was done in all the 60 patients and looked for heart axis , Right Ventricular Enlargement (RVE , Right Atrial Enlargement (RA E and Right Bundle Branch Block (RBBB. RESULTS : ECG analysis shows the features suggestive of RAE in >40% of COPD patients having duration of >10 yrs. Out of total 60 patients 24 patients had Forced Expiratory Volume First(FEV1 ≥80% (mild COPD , 30 had FEV1 50 % to 79% (moderate COPD , 5 patients had FEV1 30 - 49% (severe COPD and 1 patient had FEV1 < 30% (very severe COPD. When the disease severity is compared with the Manifestations in ECG RAE , RVE and RBBB was found in 3 (60% of the patients out of 5 patients who had severe disease. CONCLUSION : The prevalence of ECG abnormalities related to cardiac diseases , in general is higher in those with more severe pulmonary obstruction and ECG findings should be taken into consideration when diagnosing these pa tients of COPD for delivering a more integrated pulmonary and cardiovascular care.

  16. Multiadaptive Bionic Wavelet Transform: Application to ECG Denoising and Baseline Wandering Reduction

    Directory of Open Access Journals (Sweden)

    Sayadi Omid

    2007-01-01

    Full Text Available We present a new modified wavelet transform, called the multiadaptive bionic wavelet transform (MABWT, that can be applied to ECG signals in order to remove noise from them under a wide range of variations for noise. By using the definition of bionic wavelet transform and adaptively determining both the center frequency of each scale together with the -function, the problem of desired signal decomposition is solved. Applying a new proposed thresholding rule works successfully in denoising the ECG. Moreover by using the multiadaptation scheme, lowpass noisy interference effects on the baseline of ECG will be removed as a direct task. The method was extensively clinically tested with real and simulated ECG signals which showed high performance of noise reduction, comparable to those of wavelet transform (WT. Quantitative evaluation of the proposed algorithm shows that the average SNR improvement of MABWT is 1.82 dB more than the WT-based results, for the best case. Also the procedure has largely proved advantageous over wavelet-based methods for baseline wandering cancellation, including both DC components and baseline drifts.

  17. Denoising of ECG signal during spaceflight using singular value decomposition

    Science.gov (United States)

    Li, Zhuo; Wang, Li

    2009-12-01

    The Singular Value Decomposition (SVD) method is introduced to denoise the ECG signal during spaceflight. The theory base of SVD method is given briefly. The denoising process of the strategy is presented combining a segment of real ECG signal. We improve the algorithm of calculating Singular Value Ratio (SVR) spectrum, and propose a constructive approach of analysis characteristic patterns. We reproduce the ECG signal very well and compress the noise effectively. The SVD method is proved to be suitable for denoising the ECG signal.

  18. 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.

  19. Extract fetal ECG from single-lead abdominal ECG by de-shape short time Fourier transform and nonlocal median

    CERN Document Server

    Li, Su

    2016-01-01

    The multiple fundamental frequency detection problem and the source separation problem from a single-channel signal containing multiple oscillatory components and a nonstationary noise are both challenging tasks. To extract the fetal electrocardiogram (ECG) from a single-lead maternal abdominal ECG, we face both challenges. In this paper, we propose a novel method to extract the fetal ECG signal from the single channel maternal abdominal ECG signal, without any additional measurement. The algorithm is composed of three main ingredients. First, the maternal and fetal heart rates are estimated by the de-shape short time Fourier transform, which is a recently proposed nonlinear time-frequency analysis technique; second, the beat tracking technique is applied to accurately obtain the maternal and fetal R peaks; third, the maternal and fetal ECG waveforms are established by the nonlocal median. The algorithm is evaluated on a simulated fetal ECG signal database ({\\em fecgsyn} database), and tested on two real data...

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

    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...... and to assess the retention of skills using multiple follow-up intervals. METHODS: 203 medical students were included in the study. All participants completed a pre-test, an ECG tutorial, and a post-test. The participants were also randomised to complete a retention-test after short (2-4 weeks), medium (10.......6), respectively). When comparing the pre-test to retention-test delta scores, junior students had learned significantly more than senior students (junior students improved 10.7 points and senior students improved 4.7 points, p = 0.003). CONCLUSION: A standalone web-based ECG tutorial can be an effective means...

  1. Spectral Statistics of RR Intervals in ECG

    CERN Document Server

    Martinis, M; Knezevic, A; Crnugelj, J

    2003-01-01

    The statistical properties (fluctuations) of heartbeat intervals (RR intervals) in ECG are studied and compared with the predictions of Random Matrix Theory (RMT). It is found that heartbeat intervals only locally exhibit the fluctuation patterns (universality) predicted by the RMT. This finding shows that heartbeat dynamics is of the mixed type where regular and irregular (chaotic) regimes coexist and the Berry-Robnik theory can be applied. It is also observed that the distribution of heartbeat intervals is well described by the one-parameter Brody distribution. The parameter $\\beta $ of the Brody distribution is seen to be connected with the dynamical state of the heart.

  2. The Research of ECG Signal Automatic Segmentation Algorithm Based on Fractal Dimension Trajectory

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>In this paper a kind of ECG signal automatic segmentation algorithm based on ECG fractal dimension trajectory is put forward.First,the ECG signal will be analyzed,then constructing the fractal dimension trajectory of ECG signal according to the fractal dimension trajectory constructing algorithm,finally,obtaining ECG signal feature points and ECG automatic segmentation will be realized by the feature of ECG signal fractal dimension trajectory and the feature of ECG frequency domain characteristics.Through Matlab simulation of the algorithm,the results showed that by constructing the ECG fractal dimension trajectory enables ECG location of each component displayed clearly and obtains high success rate of sub-ECG,providing a basis to identify the various components of ECG signal accurately.

  3. QT interval variability in body surface ECG : measurement, physiological basis, and clinical value: position statement and consensus guidance endorsed by the European Heart Rhythm Association jointly with the ESC Working Group on Cardiac Cellular Electrophysiology

    NARCIS (Netherlands)

    Baumert, Mathias; Porta, Alberto; Vos, Marc A; Malik, Marek; Couderc, Jean-Philippe; Laguna, Pablo; Piccirillo, Gianfranco; Smith, Godfrey L; Tereshchenko, Larisa G; Volders, Paul G A

    2016-01-01

    This consensus guideline discusses the electrocardiographic phenomenon of beat-to-beat QT interval variability (QTV) on surface electrocardiograms. The text covers measurement principles, physiological basis, and clinical value of QTV. Technical considerations include QT interval measurement and the

  4. The evolution of ambulatory ECG monitoring.

    Science.gov (United States)

    Kennedy, Harold L

    2013-01-01

    Ambulatory Holter electrocardiographic (ECG) monitoring has undergone continuous technological evolution since its invention and development in the 1950s era. With commercial introduction in 1963, there has been an evolution of Holter recorders from 1 channel to 12 channel recorders with increasingly smaller storage media, and there has evolved Holter analysis systems employing increasingly technologically advanced electronics providing a myriad of data displays. This evolution of smaller physical instruments with increasing technological capacity has characterized the development of electronics over the past 50 years. Currently the technology has been focused upon the conventional continuous 24 to 48 hour ambulatory ECG examination, and conventional extended ambulatory monitoring strategies for infrequent to rare arrhythmic events. However, the emergence of the Internet, Wi-Fi, cellular networks, and broad-band transmission has positioned these modalities at the doorway of the digital world. This has led to an adoption of more cost-effective strategies to these conventional methods of performing the examination. As a result, the emergence of the mobile smartphone coupled with this digital capacity is leading to the recent development of Holter smartphone applications. The potential of point-of-care applications utilizing the Holter smartphone and a vast array of new non-invasive sensors is evident in the not too distant future. The Holter smartphone is anticipated to contribute significantly in the future to the field of global health.

  5. ECG is an inefficient screening-tool for left ventricular hypertrophy in normotensive African children population

    Directory of Open Access Journals (Sweden)

    Giuseppe Di Gioia

    2016-09-01

    Full Text Available Background Left ventricular hypertrophy (LVH is a marker of pediatric hypertension and predicts development of cardiovascular events. Electrocardiography (ECG screening is used in pediatrics to detect LVH thanks to major accessibility, reproducibility and easy to use compared to transthoracic echocardiography (TTE, that remains the standard technique. Several diseases were previously investigated, but no data exists regarding our study population. The aim of our study was to evaluate the relationship between electrocardiographic and echocardiographic criteria of LVH in normotensive African children. Methods We studied 313 children (mean age 7,8 ± 3 yo, in north-Madagascar. They underwent ECG and TTE. Sokolow-Lyon index was calculated to identify ECG-LVH (>35 mm. Left ventricle mass (LVM with TTE was calculated and indexed by height2.7 (LVMI2.7 and weight (LVMIw. We report the prevalence of TTE-LVH using three methods: (1 calculating percentiles age- and sex- specific with values >95th percentile identifying LVH; (2 LVMI2.7 >51 g/m2.7; (3 LVMIw >3.4 g/weight. Results 40 (13% children showed LVMI values >95th percentile, 24 children (8% an LVMI2.7 >51 g/m2.7 while 19 children (6% an LVMIw >3.4 g/kg. LVH-ECG by Sokolow-Lyon index was present in five, three and three children respectively, with poor values of sensitivity (ranging from 13 to 16%, positive predictive value (from 11 to 18% and high values of specificity (up to 92%. The effects of anthropometrics parameters on Sokolow-Lyon were analyzed and showed poor correlation. Conclusion ECG is a poor screening test for detecting LVH in children. In clinical practice, TTE remains the only tool to be used to exclude LVH.

  6. Brugada Syndrome ECG Is Highly Prevalent in Schizophrenia

    NARCIS (Netherlands)

    Blom, Marieke T.; Cohen, Dan; Seldenrijk, Adrie; Penninx, Brenda W. J. H.; Nijpels, Giel; Stehouwer, Coen D. A.; Dekker, Jacqueline M.; Tan, Hanno L.

    2014-01-01

    Background The causes of increased risk of sudden cardiac death in schizophrenia are not resolved. We aimed to establish (1) whether ECG markers of sudden cardiac death risk, in particular Brugada-ECG pattern, are more prevalent among patients with schizophrenia, and (2) whether increased prevalence

  7. Advances in Modern Capacitive ECG Systems for Continuous Cardiovascular Monitoring

    Directory of Open Access Journals (Sweden)

    A. Schommartz

    2011-01-01

    Full Text Available The technique of capacitive electrocardiography (cECG is very promising in a flexible manner. Already integrated into several everyday objects, the single lead cECG system has shown that easy-to-use measurements of electrocardiograms are possible without difficult preparation of the patients. Multi-channel cECG systems enable the extraction of ECG signals even in the presence of coupled interferences, due to the additional redundant information. Thus, this paper presents challenges for electronic hardware design to build on developments in recent years, going from the one-lead cECG system to multi-channel systems in order to provide robust measurements - e.g. even while driving an automobile.

  8. Noncontact ECG system for unobtrusive long-term monitoring.

    Science.gov (United States)

    McDonald, Neil J; Anumula, Harini A; Duff, Eric; Soussou, Walid

    2012-01-01

    This paper describes measurements made using an ECG system with QUASAR's capacitive bioelectrodes integrated into a pad system that is placed over a chair. QUASAR's capacitive bioelectrode has the property of measuring bioelectric potentials at a small separation from the body. This enables the measurement of ECG signals through fabric, without the removal of clothing or preparation of skin. The ECG was measured through the subject's clothing while the subject sat in the chair without any supporting action from the subject. The ECG pad system is an example of a high compliance system that places minimal requirements upon the subject and, consequently, can be used to generate a long-term record from ECG segments collected on a daily basis, providing valuable information on long-term trends in cardiac health.

  9. Adaptive Non-Linear Bayesian Filter for ECG Denoising

    Directory of Open Access Journals (Sweden)

    Mitesh Kumar Sao

    2014-06-01

    Full Text Available The cycles of an electrocardiogram (ECG signal contain three components P-wave, QRS complex and the T-wave. Noise is present in cardiograph as signals being measured in which biological resources (muscle contraction, base line drift, motion noise and environmental resources (power line interference, electrode contact noise, instrumentation noise are normally pollute ECG signal detected at the electrode. Visu-Shrink thresholding and Bayesian thresholding are the two filters based technique on wavelet method which is denoising the PLI noisy ECG signal. So thresholding techniques are applied for the effectiveness of ECG interval and compared the results with the wavelet soft and hard thresholding methods. The outputs are evaluated by calculating the root mean square (RMS, signal to noise ratio (SNR, correlation coefficient (CC and power spectral density (PSD using MATLAB software. The clean ECG signal shows Bayesian thresholding technique is more powerful algorithm for denoising.

  10. A novel similarity comparison approach for dynamic ECG series.

    Science.gov (United States)

    Yin, Hong; Zhu, Xiaoqian; Ma, Shaodong; Yang, Shuqiang; Chen, Liqian

    2015-01-01

    The heart sound signal is a reflection of heart and vascular system motion. Long-term continuous electrocardiogram (ECG) contains important information which can be helpful to prevent heart failure. A single piece of a long-term ECG recording usually consists of more than one hundred thousand data points in length, making it difficult to derive hidden features that may be reflected through dynamic ECG monitoring, which is also very time-consuming to analyze. In this paper, a Dynamic Time Warping based on MapReduce (MRDTW) is proposed to make prognoses of possible lesions in patients. Through comparison of a real-time ECG of a patient with the reference sets of normal and problematic cardiac waveforms, the experimental results reveal that our approach not only retains high accuracy, but also greatly improves the efficiency of the similarity measure in dynamic ECG series.

  11. 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.

  12. 15 Minutes of Shame? Copyright Issues in Celebrity Sex Videos

    OpenAIRE

    Rosenfeld, Shelly

    2013-01-01

    It's the tape that launched a thousand clips Paris Hilton's Celebrity Sex Video became a form of "Must See TV". Celebrities are used to performing for the camera. But when Hilton was caught on video, she reacted as many participants do when their celebrity sex tapes are revealed they file a lawsuit. This article explores the vario...

  13. A practical approach for a patient-tailored dose protocol in coronary CT angiography using prospective ECG triggering

    NARCIS (Netherlands)

    Dijk, van J.D.; Huizing, E.D.; Jager, P.L.; Ottervanger, J.P.; Knollema, S.; Slump, C.H.; Dalen, van J.A.

    2015-01-01

    To derive and validate a practical patient-specific dose protocol to obtain an image quality, expressed by the image noise, independent of patients’ size and a better radiation dose justification in coronary CT angiography (CCTA) using prospective ECG triggering. 43 patients underwent clinically ind

  14. Reduced Comparator Flash ADC for ECG Applications

    Directory of Open Access Journals (Sweden)

    Saravanan. V. A

    2013-03-01

    Full Text Available A CMOS based low power 4-bit Flash Analog to Digital Converter (ADC design with reduced number of comparators than the conventional Flash Analog to Digital Converter and multiplexer based architecture is proposed. For improving the conversion rate, both the analog and digital parts of the ADC are fully modified and the architecture uses only 4 comparators instead of 15 as used in conventional flash ADC, thus saving considerable amount of power. The proposed 4-bit ADC is designed and simulated in TANNER tools with 1.2 V supply voltage using TSpice simulation. The proposed design consumes low power of 2.15mW and operates at a faster rate hence it is suitable for ECG applications.

  15. Residual motion compensation in ECG-gated interventional cardiac vasculature reconstruction

    Science.gov (United States)

    Schwemmer, C.; Rohkohl, C.; Lauritsch, G.; Müller, K.; Hornegger, J.

    2013-06-01

    Three-dimensional reconstruction of cardiac vasculature from angiographic C-arm CT (rotational angiography) data is a major challenge. Motion artefacts corrupt image quality, reducing usability for diagnosis and guidance. Many state-of-the-art approaches depend on retrospective ECG-gating of projection data for image reconstruction. A trade-off has to be made regarding the size of the ECG-gating window. A large temporal window is desirable to avoid undersampling. However, residual motion will occur in a large window, causing motion artefacts. We present an algorithm to correct for residual motion. Our approach is based on a deformable 2D-2D registration between the forward projection of an initial, ECG-gated reconstruction, and the original projection data. The approach is fully automatic and does not require any complex segmentation of vasculature, or landmarks. The estimated motion is compensated for during the backprojection step of a subsequent reconstruction. We evaluated the method using the publicly available CAVAREV platform and on six human clinical datasets. We found a better visibility of structure, reduced motion artefacts, and increased sharpness of the vessels in the compensated reconstructions compared to the initial reconstructions. At the time of writing, our algorithm outperforms the leading result of the CAVAREV ranking list. For the clinical datasets, we found an average reduction of motion artefacts by 13 ± 6%. Vessel sharpness was improved by 25 ± 12% on average.

  16. ECG signals denoising using wavelet transform and independent component analysis

    Science.gov (United States)

    Liu, Manjin; Hui, Mei; Liu, Ming; Dong, Liquan; Zhao, Zhu; Zhao, Yuejin

    2015-08-01

    A method of two channel exercise electrocardiograms (ECG) signals denoising based on wavelet transform and independent component analysis is proposed in this paper. First of all, two channel exercise ECG signals are acquired. We decompose these two channel ECG signals into eight layers and add up the useful wavelet coefficients separately, getting two channel ECG signals with no baseline drift and other interference components. However, it still contains electrode movement noise, power frequency interference and other interferences. Secondly, we use these two channel ECG signals processed and one channel signal constructed manually to make further process with independent component analysis, getting the separated ECG signal. We can see the residual noises are removed effectively. Finally, comparative experiment is made with two same channel exercise ECG signals processed directly with independent component analysis and the method this paper proposed, which shows the indexes of signal to noise ratio (SNR) increases 21.916 and the root mean square error (MSE) decreases 2.522, proving the method this paper proposed has high reliability.

  17. Flexible Graphene Electrodes for Prolonged Dynamic ECG Monitoring

    Directory of Open Access Journals (Sweden)

    Cunguang Lou

    2016-11-01

    Full Text Available This paper describes the development of a graphene-based dry flexible electrocardiography (ECG electrode and a portable wireless ECG measurement system. First, graphene films on polyethylene terephthalate (PET substrates and graphene paper were used to construct the ECG electrode. Then, a graphene textile was synthesized for the fabrication of a wearable ECG monitoring system. The structure and the electrical properties of the graphene electrodes were evaluated using Raman spectroscopy, scanning electron microscopy (SEM, and alternating current impedance spectroscopy. ECG signals were then collected from healthy subjects using the developed graphene electrode and portable measurement system. The results show that the graphene electrode was able to acquire the typical characteristics and features of human ECG signals with a high signal-to-noise (SNR ratio in different states of motion. A week-long continuous wearability test showed no degradation in the ECG signal quality over time. The graphene-based flexible electrode demonstrates comfortability, good biocompatibility, and high electrophysiological detection sensitivity. The graphene electrode also combines the potential for use in long-term wearable dynamic cardiac activity monitoring systems with convenience and comfort for use in home health care of elderly and high-risk adults.

  18. ECG signal analysis with wavelets and neural networks in FPGA

    OpenAIRE

    Klaus Raizer

    2010-01-01

    Resumo: Este trabalho apresenta a implementação de um sistema de análise de sinais de ECGs (eletrocardiogramas) embarcado em FPGA (field programmable gate array), capaz de classificar cardiopatias. A análise de ECGs é de grande importância devido a sua natureza potencialmente não-invasiva, baixo custo e alta eficiência na identificação de patologias cardíacas. Visto que um sinal de ECG pode ser composto por horas de gravação da atividade cardíaca, uma abordagem computacional para a sua anális...

  19. [Informative value of programmed electric stimulation of the ventricles, 24-hour ECG monitoring and bicycle ergometry in the diagnosis of electric instability of the myocardium in various clinical variants of stenocardia].

    Science.gov (United States)

    Makhotina, V N; Rimsha, E; Kaĭk, Iu

    1991-01-01

    The informative value of programmed ventricular pacing (PVP), Holter monitoring (HM), and bicycle ergometry (BEM) in the diagnosis of myocardial electric instability was assessed in various clinical types of angina pectoris. An examination was made of 20 patients with first exercise-induced angina (FEIA), 33 with progressive exercise-induced angina (PEIA), 17 with spontaneous angina (SA), 30 with stable exercise-induced angina (SEIA), and postinfarction angina. Myocardial electric instability was estimated from HM and BEM findings in patients with FEIA, SA, as well as in PEIA, SEIA in the presence of preserved myocardial contractility as evidenced by ventriculography. A clear-cut correlation was found between transient myocardial ischemia and the occurrence of high-grade ventricular arrhythmias for the patients from the above-mentioned groups. Lower myocardial contractility despite the nature of angina is an indication for PVP.

  20. ST segment depression in hypertensive patients: A comparison of exercise test versus Holter ECG

    Directory of Open Access Journals (Sweden)

    Sakir Uen

    2008-10-01

    Full Text Available Sakir Uen1, Rolf Fimmers2, Burkhard Weisser3, Osman Balta1, Georg Nickenig1, Thomas Mengden11Division of Hypertension and Vascular Medicine, Department of Internal Medicine II, University Clinic, Bonn, Germany; 2Department of Biometry and Medical Statistics, University of Bonn, Bonn, Germany; 3Department of Sports Medicine, University of Kiel, Kiel, GermanyIntroduction: This study compared ST segment depression (ST depression during cycle ergometry (ergometry versus simultaneous 24-hour ambulatory blood pressure measurement and electrocardiogram recording (24-h ABPM/ECG during everyday life.Methods: In a German multicenter study, ergometry and 24-h ABPM/ECG records of 239 hypertensive patients were retrospectively analyzed. ST depression was defined as an ST segment depression (1 mm limb or chest recordings V1 to V6 in an incremental cycle ergometry, or 1 mm in the 24-h ABPM/ECG recording under everyday conditions. Blood pressure parameters at the onset of ST depression in the context of the respective method were compared.Results: 18 patients had ST depression only in ergometry (group B, 23 had ST depression only during 24-h ABPM/ECG monitoring (group C and 28 patients had ST depression with both methods (group D. Group A had no ST depression with any method. In group D, at the onset of ST depression with 24-h ABPM/ECG investigation, all parameters except diastolic blood pressure were significantly lower compared with the corresponding parameters at the onset of ST depression with ergometry (systolic blood pressure: 148 ± 19 vers 188 ± 35 mmHg, p < 0.001; heart rate: 93 ± 12 vs 120 ± 21 beat/min, p < 0.0001; double product: 13,714 ± 2315 vs 22,992 ± 3,985 mmHg/min, p < 0.0001.Conclusion: ST depressions during everyday life detected by 24-h ABPM/ECG are characterized by a substantially lower triggering threshold for blood pressure level parameters compared with ergometry. The two methods detecting ischemia do not replace but complement

  1. Dual-source computed tomography: Estimation of radiation exposure of ECG-gated and ECG-triggered coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Ketelsen, Dominik [Department of Diagnostic and Interventional Radiology, University Hospital Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen (Germany)], E-mail: dominik.ketelsen@med.uni-tuebingen.de; Thomas, Christoph; Werner, Matthias; Luetkhoff, Marie H. [Department of Diagnostic and Interventional Radiology, University Hospital Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen (Germany); Buchgeister, Markus [Departments of Radiotherapy and Radiooncology, University Hospital Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen (Germany); Tsiflikas, Ilias; Reimann, Anja [Department of Diagnostic and Interventional Radiology, University Hospital Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen (Germany); Burgstahler, Christof [Department of Cardiology, University Hospital Tuebingen, Ottfried-Mueller-Strasse 10, 72076 Tuebingen (Germany); Brodoefel, Harald; Kopp, Andreas F.; Claussen, Claus D.; Heuschmid, Martin [Department of Diagnostic and Interventional Radiology, University Hospital Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen (Germany)

    2010-02-15

    Purpose: The aim of the study was to estimate radiation exposure of coronary calcium scoring and angiography using ECG-gated and ECG-triggered dual-source computed tomography. Materials and methods: An Alderson Rando phantom equipped with thermoluminescent dosimeters was used for all dose measurements. Effective dose was calculated according to ICRP 103. Radiation exposure was performed on a dual-source computed tomography (DSCT) scanner with standard protocols for calcium scoring (DSCT-Ca) and coronary angiography (DSCTA) at different heart rates (40-100 beats/min). Furthermore, a scanning protocol with ECG-triggering as well as a standard chest CT scan were evaluated. Results: Depending on gender, heart rate and ECG-pulsing, the effective dose of a complete cardiac DSCT (DSCT-Ca and DSCTA) scan varies from 10.2 to 32.6 mSv. The effective radiation dose increased significantly with lower heart rates (p < 0.035). ECG-pulsing reduced the radiation exposure significantly in DSCTA (p < 0.001). Due to breast tissue in the primary scan range, females' doses showed an increase up to 69.9% compared to males in scan protocols without ECG-pulsing. Prospective ECG-triggered DSCTA resulted in estimated effective doses from 2.8 mSv (males) to 4.1 mSv (females). Conclusion: The ECG-pulsing technique has proven its effectiveness to reduce effective dose in coronary CT angiography and is recommended for all patients with regular heart rates. The patient's heart rate influences the radiation exposure with a significant decrease at higher heart rates. Due to its lower dose, ECG-triggered DSCTA should be implemented for special indications, i.e. for diagnosis of pathologies of the aortic root and the ascending aorta.

  2. The 24-lead ECG display for enhanced recognition of STEMI-equivalent patterns in the 12-lead ECG.

    Science.gov (United States)

    Pahlm, Ulrika; Pahlm, Olle; Wagner, Galen S

    2014-01-01

    In a patient with chest pain and suspected acute coronary syndrome, the electrocardiogram (ECG) is the only readily available diagnostic tool. It is important to maximize its usefulness to detect acute myocardial ischemia that may evolve to myocardial infarction unless the patient is treated expediently with reperfusion therapy. Since diagnostic guidelines have usually included only ST-elevation myocardial infarction (STEMI) as the entity that should be diagnosed and treated urgently, a patient with coronary occlusion represented on ECG as ST depression is likely not to be considered a candidate for receiving immediate coronary angiography and coronary intervention. ECG criteria for STEMI detection require that ST elevation meet predetermined millivolt thresholds and appear in at least two spatially contiguous ECG leads. The typical ECG reader recognizes only three contiguous pairs: aVL and I; II and aVF; aVF and III. However, viewing the "orderly sequenced" 12-lead ECG display, two more contiguous pairs become obvious in the frontal plane: +I and -aVR; -aVR and +II. The 24-lead ECG is a display of the standard 12-lead ECG as both the classical positive leads and their negative (inverted) counterparts. Leads +V1, +V2, +V3, +V4, +V5, and +V6 and their inverted counterparts are used to generate a "clock-face display" for the transverse plane. Similarly, +aVL, +I, -aVR, +II, +aVF, +III in the frontal plane and their inverted counterparts are used to generate a clock-face display for the frontal plane. Optimum results, 78% sensitivity and 93% specificity, were obtained using the following 19 ECG leads: frontal plane: +aVR, -III, +aVL, +I, -aVR, +II, +aVF, +III, -aVL; transverse plane: +V1, +V2, +V3, +V4, +V5, +V6, -V1, -V2, -V3.

  3. Wireless Self-Acquistion of 12-Lead ECG via Android Smart Phone

    Science.gov (United States)

    Schlegel, Todd T.

    2012-01-01

    Researchers at NASA s Johnson Space Center and at Orbital Research, Inc. (a NASA SBIR grant recipient) have recently developed a dry-electrode harness that allows for self-acquisition of resting 12-lead ECGs by minimally trained laypersons. When used in conjunction with commercial wireless (e.g., Bluetooth(TM) or 802.11-enabled) 12-lead ECG devices and custom smart phone-based software, the collected 12-lead ECG data can also immediately be forwarded from any geographic location within cellular range to the user s physician(s) of choice. The system can also be used to immediately forward to central receiving stations 12-lead ECG data collected during space flight or during activities in any remote terrestrial location supported by an internet or cellular phone infrastructure. The main novel aspects of the system are first, the dry-electrode 12-lead ECG harness itself, and second, an accompanying Android(TM) smart phone-based wireless 12-lead ECG capability. The ECG harness nominally employs dry electrodes manufactured by Orbital Research, Inc, recently cleared through the Food and Drug Administration (FDA). However, other dry electrodes that are not yet FDA cleared, for example those recently developed by Nanosonic, Inc as part of another NASA SBIR grant, can also be used. The various advantageous features of the harness include: 1) laypersons can be quickly instructed on its correct use, remotely if necessary; 2) all tangled "leadwire spaghetti" is eliminated, as is the common clinical problem of "leadwire reversal"; 3) all adhesives and disposables are also eliminated, the harness being fully reusable; if multiple individuals intend to use use the same harness, then standard antimicrobial wipes can be employed to sterilize the dry electrodes (and harness surface if needed) between users; 5) padded cushions at the lateral sides of the torso function to press the left arm (LA) and right arm (RA) dry electrodes mounted on the cushions against sideward or downward

  4. 妊娠晚期心电图的异常分析%Analysis of ECG Abnormalities in Late Pregnancy

    Institute of Scientific and Technical Information of China (English)

    吐逊古•阿西木; 迪丽拜尔•克尤木

    2014-01-01

    Objective The ecg changes in late pregnancy women and the relationship between the clinical and treatment method.Methods The guangdong state built ECG- 9803 type routine eeg, ECG machine, analysis the change of electrocardiogram (ECG), 148 cases of late pregnancy women.Results The types of abnormal ecg in 148 cases of late pregnancy women were,electrical axis left 75 cases,40 cases of sinus tachycardia,sinus arrhythmia,12 cases were shortened period between P-R 10 cases,5 cases of premature beat,QRS low voltage 4 cases,S T-T change in 2 cases.Conclusion See more quite late pregnancy women abnormal ecg, should be focus on change, timely intervention treatment when necessary, to ensure life safety of pregnant women and fetus.%目的探讨妊娠晚期妇女心电图改变与临床的关系及处理方法。方法采用美国M 1772A型心电图机进行常规描记,分析148例妊娠晚期女性的心电图的改变。结果148例孕晚期妇女中心电图异常的种类分别是,电轴左偏75例,窦性心动过速40例、窦性心律不齐12例,P-R间期缩短10例、早搏5例、QRS低电压4例,ST-T改变2例。结论妊娠晚期妇女心电图异常比较多见,应予关注改变,必要时及时进行干预治疗,以保障孕妇和胎儿的生命安全。

  5. A harmonic linear dynamical system for prominent ECG feature extraction.

    Science.gov (United States)

    Thi, Ngoc Anh Nguyen; Yang, Hyung-Jeong; Kim, SunHee; Do, Luu Ngoc

    2014-01-01

    Unsupervised mining of electrocardiography (ECG) time series is a crucial task in biomedical applications. To have efficiency of the clustering results, the prominent features extracted from preprocessing analysis on multiple ECG time series need to be investigated. In this paper, a Harmonic Linear Dynamical System is applied to discover vital prominent features via mining the evolving hidden dynamics and correlations in ECG time series. The discovery of the comprehensible and interpretable features of the proposed feature extraction methodology effectively represents the accuracy and the reliability of clustering results. Particularly, the empirical evaluation results of the proposed method demonstrate the improved performance of clustering compared to the previous main stream feature extraction approaches for ECG time series clustering tasks. Furthermore, the experimental results on real-world datasets show scalability with linear computation time to the duration of the time series.

  6. A Harmonic Linear Dynamical System for Prominent ECG Feature Extraction

    Directory of Open Access Journals (Sweden)

    Ngoc Anh Nguyen Thi

    2014-01-01

    Full Text Available Unsupervised mining of electrocardiography (ECG time series is a crucial task in biomedical applications. To have efficiency of the clustering results, the prominent features extracted from preprocessing analysis on multiple ECG time series need to be investigated. In this paper, a Harmonic Linear Dynamical System is applied to discover vital prominent features via mining the evolving hidden dynamics and correlations in ECG time series. The discovery of the comprehensible and interpretable features of the proposed feature extraction methodology effectively represents the accuracy and the reliability of clustering results. Particularly, the empirical evaluation results of the proposed method demonstrate the improved performance of clustering compared to the previous main stream feature extraction approaches for ECG time series clustering tasks. Furthermore, the experimental results on real-world datasets show scalability with linear computation time to the duration of the time series.

  7. Sampling Rate Independent Filtration Approach for Automatic ECG Delineation

    CERN Document Server

    Chereda, Hryhorii; Tymoshenko, Yury

    2016-01-01

    In this paper different types of ECG automatic delineation approaches were overviewed. A combination of these approaches was used to create sampling rate independent filtration algorithm for automatic ECG delineation that is capable of distinguishing different morphologies of T and P waves and QRS complexes. Created filtration algorithm was compared with algorithme \\`a trous. It was investigated that continuous wavelets transform with proposed automatic adaptation for different sampling rates procedure can be used for delineation problem.

  8. Human ECG signal parameters estimation during controlled physical activity

    Science.gov (United States)

    Maciejewski, Marcin; Surtel, Wojciech; Dzida, Grzegorz

    2015-09-01

    ECG signal parameters are commonly used indicators of human health condition. In most cases the patient should remain stationary during the examination to decrease the influence of muscle artifacts. During physical activity, the noise level increases significantly. The ECG signals were acquired during controlled physical activity on a stationary bicycle and during rest. Afterwards, the signals were processed using a method based on Pan-Tompkins algorithms to estimate their parameters and to test the method.

  9. A robust and simple security extension for the medical standard SCP-ECG.

    Science.gov (United States)

    Rubio, Oscar J; Alesanco, Alvaro; García, José

    2013-02-01

    This paper proposes a SCP-ECG security extension after having analyzed the features of this standard, its security requirements and the current measures implemented by other medical protocols. Our approach permits SCP-ECG files to be stored safely and proper access to be granted (or denied) to users for different purposes: interpretation of the test, consultation, clinical research or teaching. The access privileges are scaled by means of role-based profiles supported by cryptographic elements (ciphering, digital certificates and digital signatures). These elements are arranged as metadata into a new section which extends the protocol and protects the remaining sections. The application built to implement this approach has been extensively tested, showing its capacity to authenticate users and to protect the integrity of files and the privacy of sensitive data, with a low impact on file size and access time. In addition, this solution is compatible with any version of the SCP-ECG and can be easily integrated into e-health platforms.

  10. Sudden cardiac arrest risk stratification based on 24-hour Holter ECG statistics.

    Science.gov (United States)

    Kasahara, Keisuke; Shiobara, Masahito; Nakamura, Saya; Yamashiro, Koichiro; Yana, Kazuo; Ono, Takuya

    2015-08-01

    This study examined the feasibility of using indices obtained from a long term Holter ECG record for sudden cardiac arrest (SCA) risk stratification. The ndices tested were the QT-RR interval co-variability and the alternans ratio percentile (ARP(θ)) which is defined as the θ(th) percentile of alternans ratios over a 24 hour period. The QT-RR interval co-variabilities are evaluated by the serial correlation coefficient between QT and RR trend sequences (QTRC). Previously reported Kalman filter technique and a simple smoothing spline method for the trend estimation are compared. Parameter θ in the alternans ratio percentile index was optimized to achieve the best classification accuracy. These indices were estimated from 26 cardiovascular outpatients for Holter ECG record. Patients were classified into high and low risk groups according to their clinical diagnosis, and the obtained indices were compared with those of 25 control subjects. A risk stratification using the two indices QTRC and ARP(θ) yielded an average sensitivity of 0.812 and a specificity of 0.925. The sensitivities and specificities of all three categories exceeded 0.8 except for the sensitivity to detect the high-risk patient group. Other short-term ECG parameters may need to be incorporated in order to improve the sensitivity.

  11. Architecture design of the multi-functional wavelet-based ECG microprocessor for realtime detection of abnormal cardiac events.

    Science.gov (United States)

    Cheng, Li-Fang; Chen, Tung-Chien; Chen, Liang-Gee

    2012-01-01

    Most of the abnormal cardiac events such as myocardial ischemia, acute myocardial infarction (AMI) and fatal arrhythmia can be diagnosed through continuous electrocardiogram (ECG) analysis. According to recent clinical research, early detection and alarming of such cardiac events can reduce the time delay to the hospital, and the clinical outcomes of these individuals can be greatly improved. Therefore, it would be helpful if there is a long-term ECG monitoring system with the ability to identify abnormal cardiac events and provide realtime warning for the users. The combination of the wireless body area sensor network (BASN) and the on-sensor ECG processor is a possible solution for this application. In this paper, we aim to design and implement a digital signal processor that is suitable for continuous ECG monitoring and alarming based on the continuous wavelet transform (CWT) through the proposed architectures--using both programmable RISC processor and application specific integrated circuits (ASIC) for performance optimization. According to the implementation results, the power consumption of the proposed processor integrated with an ASIC for CWT computation is only 79.4 mW. Compared with the single-RISC processor, about 91.6% of the power reduction is achieved.

  12. 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.

  13. [ECG abnormalities in the MONICA Gent-Charleroi study population].

    Science.gov (United States)

    De Backer, G

    1989-01-01

    In a survey of a random sample of the adult population (aged 25-64 yr) from Ghent and Charleroi (n = 1693), 103 (6.1%) showed ECG-abnormalities suggestive of coronary heart disease (Minnesota code I, IV, or V); prevalence was equal in men (6.2%) as in women (6.0%). In men, 30% of ECG-abnormalities suggested an old myocardial infarction as compared to 23.4% in women. Men with abnormal ECG had a positive history of acute myocardial infarction in 23%, as compared to 23.4% in women. Multivariate discriminant function analysis shows that men with abnormal ECG are older, have a higher systolic blood pressure and were more often married. Women with ECG abnormalities were significantly older, had a lower HDL-level and were less educated. So, although the prevalence of ECG abnormalities is almost similar between sexes, they correlate differently with antecedents of infarction and are poorly related to different sets of risk factors in men as compared to women.

  14. Two surgeons and the ECG-a double blind study

    Institute of Scientific and Technical Information of China (English)

    Ulf Martin Schilling

    2012-01-01

    Objective: To assess the capability of operating abdominal and orthopaedic surgeons to analyze a set of standardized ECG. Methods: Twenty operating abdominal and orthopaedic surgeons at a university hospital were included. Each participant analyzed a set of five standardized ECG with an answering scheme for eight different items, giving a maximum score of 40. The answers were matched according to specialty and experience of the doctors of less than 5 years, between 5 and 10 years or more than 10 years. The reference standard was set by two independent consultants in cardiology. Results: The mean overall score was 25.25 (63.13%±4.78%) varying between 38 (95%) and 20(50%). Abdominal surgeons performed a mean score of 27.625 (69.06%±9.53%), and orthopaedic surgeons 23.67 points (59.17%±3.69%). The difference between the performance of abdominal and orthopaedic surgeons was not significant (P=0.09). 20/20 surgeons identified ST-elevation and no surgeon accepted the ECG showing acute ST-elevation myocardial infarction as normal. Conclusions: Abdominal and orthopaedic surgeons provided an answering scheme are able to interprete the ECG and identify both the normal and the ECG showing life-threatening pathology. The hypothesis that surgeons were unable to interprete the ECG must be rejected.

  15. Combining and benchmarking methods of foetal ECG extraction without maternal or scalp electrode data.

    Science.gov (United States)

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

    2014-08-01

    Despite significant advances in adult clinical electrocardiography (ECG) signal processing techniques and the power of digital processors, the analysis of non-invasive foetal ECG (NI-FECG) is still in its infancy. The Physionet/Computing in Cardiology Challenge 2013 addresses some of these limitations by making a set of FECG data publicly available to the scientific community for evaluation of signal processing techniques.The abdominal ECG signals were first preprocessed with a band-pass filter in order to remove higher frequencies and baseline wander. A notch filter to remove power interferences at 50 Hz or 60 Hz was applied if required. The signals were then normalized before applying various source separation techniques to cancel the maternal ECG. These techniques included: template subtraction, principal/independent component analysis, extended Kalman filter and a combination of a subset of these methods (FUSE method). Foetal QRS detection was performed on all residuals using a Pan and Tompkins QRS detector and the residual channel with the smoothest foetal heart rate time series was selected.The FUSE algorithm performed better than all the individual methods on the training data set. On the validation and test sets, the best Challenge scores obtained were E1 = 179.44, E2 = 20.79, E3 = 153.07, E4 = 29.62 and E5 = 4.67 for events 1-5 respectively using the FUSE method. These were the best Challenge scores for E1 and E2 and third and second best Challenge scores for E3, E4 and E5 out of the 53 international teams that entered the Challenge. The results demonstrated that existing standard approaches for foetal heart rate estimation can be improved by fusing estimators together. We provide open source code to enable benchmarking for each of the standard approaches described.

  16. e-SCP-ECG+ Protocol: An Expansion on SCP-ECG Protocol for Health Telemonitoring—Pilot Implementation

    Directory of Open Access Journals (Sweden)

    George J. Mandellos

    2010-01-01

    Full Text Available Standard Communication Protocol for Computer-assisted Electrocardiography (SCP-ECG provides standardized communication among different ECG devices and medical information systems. This paper extends the use of this protocol in order to be included in health monitoring systems. It introduces new sections into SCP-ECG structure for transferring data for positioning, allergies, and five additional biosignals: noninvasive blood pressure (NiBP, body temperature (Temp, Carbon dioxide (CO2, blood oxygen saturation (SPO2, and pulse rate. It also introduces new tags in existing sections for transferring comprehensive demographic data. The proposed enhanced version is referred to as e-SCP-ECG+ protocol. This paper also considers the pilot implementation of the new protocol as a software component in a Health Telemonitoring System.

  17. Standard-compliant real-time transmission of ECGs: harmonization of ISO/IEEE 11073-PHD and SCP-ECG.

    Science.gov (United States)

    Trigo, Jesús D; Chiarugi, Franco; Alesanco, Alvaro; Martínez-Espronceda, Miguel; Chronaki, Catherine E; Escayola, Javier; Martínez, Ignacio; García, José

    2009-01-01

    Ambient assisted living and integrated care in an aging society is based on the vision of the lifelong Electronic Health Record calling for HealthCare Information Systems and medical device interoperability. For medical devices this aim can be achieved by the consistent implementation of harmonized international interoperability standards. The ISO/IEEE 11073 (x73) family of standards is a reference standard for medical device interoperability. In its Personal Health Device (PHD) version several devices have been included, but an ECG device specialization is not yet available. On the other hand, the SCP-ECG standard for short-term diagnostic ECGs (EN1064) has been recently approved as an international standard ISO/IEEE 11073-91064:2009. In this paper, the relationships between a proposed x73-PHD model for an ECG device and the fields of the SCP-ECG standard are investigated. A proof-of-concept implementation of the proposed x73-PHD ECG model is also presented, identifying open issues to be addressed by standards development for the wider interoperability adoption of x73-PHD standards.

  18. A Simple Method for Guaranteeing ECG Quality in Real-Time Wavelet Lossy Coding

    Directory of Open Access Journals (Sweden)

    Alesanco Álvaro

    2007-01-01

    Full Text Available Guaranteeing ECG signal quality in wavelet lossy compression methods is essential for clinical acceptability of reconstructed signals. In this paper, we present a simple and efficient method for guaranteeing reconstruction quality measured using the new distortion index wavelet weighted PRD (WWPRD, which reflects in a more accurate way the real clinical distortion of the compressed signal. The method is based on the wavelet transform and its subsequent coding using the set partitioning in hierarchical trees (SPIHT algorithm. By thresholding the WWPRD in the wavelet transform domain, a very precise reconstruction error can be achieved thus enabling to obtain clinically useful reconstructed signals. Because of its computational efficiency, the method is suitable to work in a real-time operation, thus being very useful for real-time telecardiology systems. The method is extensively tested using two different ECG databases. Results led to an excellent conclusion: the method controls the quality in a very accurate way not only in mean value but also with a low-standard deviation. The effects of ECG baseline wandering as well as noise in compression are also discussed. Baseline wandering provokes negative effects when using WWPRD index to guarantee quality because this index is normalized by the signal energy. Therefore, it is better to remove it before compression. On the other hand, noise causes an increase in signal energy provoking an artificial increase of the coded signal bit rate. Clinical validation by cardiologists showed that a WWPRD value of 10 preserves the signal quality and thus they recommend this value to be used in the compression system.

  19. A Simple Method for Guaranteeing ECG Quality in Real-Time Wavelet Lossy Coding

    Directory of Open Access Journals (Sweden)

    José García

    2007-01-01

    Full Text Available Guaranteeing ECG signal quality in wavelet lossy compression methods is essential for clinical acceptability of reconstructed signals. In this paper, we present a simple and efficient method for guaranteeing reconstruction quality measured using the new distortion index wavelet weighted PRD (WWPRD, which reflects in a more accurate way the real clinical distortion of the compressed signal. The method is based on the wavelet transform and its subsequent coding using the set partitioning in hierarchical trees (SPIHT algorithm. By thresholding the WWPRD in the wavelet transform domain, a very precise reconstruction error can be achieved thus enabling to obtain clinically useful reconstructed signals. Because of its computational efficiency, the method is suitable to work in a real-time operation, thus being very useful for real-time telecardiology systems. The method is extensively tested using two different ECG databases. Results led to an excellent conclusion: the method controls the quality in a very accurate way not only in mean value but also with a low-standard deviation. The effects of ECG baseline wandering as well as noise in compression are also discussed. Baseline wandering provokes negative effects when using WWPRD index to guarantee quality because this index is normalized by the signal energy. Therefore, it is better to remove it before compression. On the other hand, noise causes an increase in signal energy provoking an artificial increase of the coded signal bit rate. Clinical validation by cardiologists showed that a WWPRD value of 10% preserves the signal quality and thus they recommend this value to be used in the compression system.

  20. PIC microcontroller-based RF wireless ECG monitoring system.

    Science.gov (United States)

    Oweis, R J; Barhoum, A

    2007-01-01

    This paper presents a radio-telemetry system that provides the possibility of ECG signal transmission from a patient detection circuit via an RF data link. A PC then receives the signal through the National Instrument data acquisition card (NIDAQ). The PC is equipped with software allowing the received ECG signals to be saved, analysed, and sent by email to another part of the world. The proposed telemetry system consists of a patient unit and a PC unit. The amplified and filtered ECG signal is sampled 360 times per second, and the A/D conversion is performed by a PIC16f877 microcontroller. The major contribution of the final proposed system is that it detects, processes and sends patients ECG data over a wireless RF link to a maximum distance of 200 m. Transmitted ECG data with different numbers of samples were received, decoded by means of another PIC microcontroller, and displayed using MATLAB program. The designed software is presented in a graphical user interface utility.

  1. A controlled study of a new ECG electrode system.

    Science.gov (United States)

    Sheffield, L T; Roitman, D I; Kansal, S

    1978-07-01

    A newly marketed resting ECG electrode system was compared with conventional metal suction and plate electrodes, electrode cream and patient cable. Two experienced technicians were given special training in the use of the new electrode, electrolyte and patient cable system and alternated daily in using new and conventional equipment. Nearly equal numbers of perfect-scoring ECGs were recorded with each system, attesting to the impartiality of the technicians. A total of 1,062 ECGs were evaluated, 554 with the new system and 508 with the conventional one. ECG tracings were evaluated by electrocardiographers unaware of which system was used for each. A quantitative scoring system was used to measure the technical quality of each tracing in terms of baseline drift, powerline artifact and myographic plus miscellaneous artifacts. The new system received mean scores of 2.33, 3.08, and 2.72, respectively, while the conventional electrodes received scores of 2.56, 3.03 and 2.79. We concluded that the two types of electrodes produced ECGs of essentially equal quality.

  2. Shannon's Energy Based Algorithm in ECG Signal Processing

    Science.gov (United States)

    2017-01-01

    Physikalisch-Technische Bundesanstalt (PTB) database is electrocardiograms (ECGs) set from healthy volunteers and patients with different heart diseases. PTB is provided for research and teaching purposes by National Metrology Institute of Germany. The analysis method of complex QRS in ECG signals for diagnosis of heart disease is extremely important. In this article, a method on Shannon energy (SE) in order to detect QRS complex in 12 leads of ECG signal is provided. At first, this algorithm computes the Shannon energy (SE) and then makes an envelope of Shannon energy (SE) by using the defined threshold. Then, the signal peaks are determined. The efficiency of the algorithm is tested on 70 cases. Of all 12 standard leads, ECG signals include 840 leads of the PTB Diagnostic ECG Database (PTBDB). The algorithm shows that the Shannon energy (SE) sensitivity is equal to 99.924%, the detection error rate (DER) is equal to 0.155%, Positive Predictivity (+P) is equal to 99.922%, and Classification Accuracy (Acc) is equal to 99.846%.

  3. A system for intelligent home care ECG upload and priorisation.

    Science.gov (United States)

    D'Angelo, Lorenzo T; Tarita, Eugeniu; Zywietz, Tosja K; Lueth, Tim C

    2010-01-01

    In this contribution, a system for internet based, automated home care ECG upload and priorisation is presented for the first time. It unifies the advantages of existing telemonitoring ECG systems adding functionalities such as automated priorisation and usability for home care. Chronic cardiac diseases are a big group in the geriatric field. Most of them can be easily diagnosed with help of an electrocardiogram. A frequent or long-term ECG analysis allows early diagnosis of e.g. a cardiac infarction. Nevertheless, patients often aren't willing to visit a doctor for prophylactic purposes. Possible solutions of this problem are home care devices, which are used to investigate patients at home without the presence of a doctor on site. As the diffusion of such systems leads to a huge amount of data which has to be managed and evaluated, the presented approach focuses on an easy to use software for ECG upload from home, a web based management application and an algorithm for ECG preanalysis and priorisation.

  4. Fast multi-scale feature fusion for ECG heartbeat classification

    Science.gov (United States)

    Ai, Danni; Yang, Jian; Wang, Zeyu; Fan, Jingfan; Ai, Changbin; Wang, Yongtian

    2015-12-01

    Electrocardiogram (ECG) is conducted to monitor the electrical activity of the heart by presenting small amplitude and duration signals; as a result, hidden information present in ECG data is difficult to determine. However, this concealed information can be used to detect abnormalities. In our study, a fast feature-fusion method of ECG heartbeat classification based on multi-linear subspace learning is proposed. The method consists of four stages. First, baseline and high frequencies are removed to segment heartbeat. Second, as an extension of wavelets, wavelet-packet decomposition is conducted to extract features. With wavelet-packet decomposition, good time and frequency resolutions can be provided simultaneously. Third, decomposed confidences are arranged as a two-way tensor, in which feature fusion is directly implemented with generalized N dimensional ICA (GND-ICA). In this method, co-relationship among different data information is considered, and disadvantages of dimensionality are prevented; this method can also be used to reduce computing compared with linear subspace-learning methods (PCA). Finally, support vector machine (SVM) is considered as a classifier in heartbeat classification. In this study, ECG records are obtained from the MIT-BIT arrhythmia database. Four main heartbeat classes are used to examine the proposed algorithm. Based on the results of five measurements, sensitivity, positive predictivity, accuracy, average accuracy, and t-test, our conclusion is that a GND-ICA-based strategy can be used to provide enhanced ECG heartbeat classification. Furthermore, large redundant features are eliminated, and classification time is reduced.

  5. Shannon's Energy Based Algorithm in ECG Signal Processing.

    Science.gov (United States)

    Beyramienanlou, Hamed; Lotfivand, Nasser

    2017-01-01

    Physikalisch-Technische Bundesanstalt (PTB) database is electrocardiograms (ECGs) set from healthy volunteers and patients with different heart diseases. PTB is provided for research and teaching purposes by National Metrology Institute of Germany. The analysis method of complex QRS in ECG signals for diagnosis of heart disease is extremely important. In this article, a method on Shannon energy (SE) in order to detect QRS complex in 12 leads of ECG signal is provided. At first, this algorithm computes the Shannon energy (SE) and then makes an envelope of Shannon energy (SE) by using the defined threshold. Then, the signal peaks are determined. The efficiency of the algorithm is tested on 70 cases. Of all 12 standard leads, ECG signals include 840 leads of the PTB Diagnostic ECG Database (PTBDB). The algorithm shows that the Shannon energy (SE) sensitivity is equal to 99.924%, the detection error rate (DER) is equal to 0.155%, Positive Predictivity (+P) is equal to 99.922%, and Classification Accuracy (Acc) is equal to 99.846%.

  6. A novel approach for the diagnosis of ventricular tachycardia based on phase space reconstruction of ECG

    CERN Document Server

    Koulaouzidis, George; Cappiello, Grazia; Mazomenos, Evangelos B; Maharatna, Koushik; Morgan, John

    2014-01-01

    Ventricular arrhythmias comprise a group of disorders which manifest clinically in a variety of ways from ventricular premature beats (VPB) and no sustained ventricular tachycardia (in healthy subjects) to sudden cardiac death due to ventricular tachyarrhythmia in patients with and/or without structural heart disease. Ventricular fibrillation (VF) and ventricular tachycardia (VT) are the most common electrical mechanisms for cardiac arrest. Accurate and automatic recognition of these arrhythmias from electrocardiography (ECG) is a crucial task for medical professionals. The purpose of this research is to develop a new index for the differential diagnosis of normal sinus rhythm (SR) and ventricular arrhythmias, based on phase space reconstruction (PSR).

  7. A new technique of ECG analysis and its application to evaluation of disorders during ventricular tachycardia

    Energy Technology Data Exchange (ETDEWEB)

    Moskalenko, A.V. [Institute of Theoretical and Experimental Biophysics RAS, Institutskaya Street, 3, Pushchino 142290 (Russian Federation)], E-mail: info@avmoskalenko.ru; Rusakov, A.V. [Institute of Theoretical and Experimental Biophysics RAS, Institutskaya Street, 3, Pushchino 142290 (Russian Federation); Elkin, Yu.E. [Institute of Mathematical Problems of Biology RAS, Institutskaya Street, 4, Pushchino 142290 (Russian Federation)

    2008-04-15

    We propose a new technique of ECG analysis to characterize the properties of polymorphic ventricular arrhythmias, potentially life-threatening disorders of cardiac activation. The technique is based on extracting two indices from the ECG fragment. The result is a new detailed quantitative description of polymorphic ECGs. Our observations suggest that the proposed ECG processing algorithm provides information that supplements the traditional visual ECG analysis. The estimates of ECG variation in this study reveal some unexpected details of ventricular activation dynamics, which are possibly useful for diagnosing cardiac rhythm disturbances.

  8. The role of the ECG in diagnosis, risk estimation, and catheterization laboratory activation in patients with acute coronary syndromes: a consensus document.

    Science.gov (United States)

    Birnbaum, Yochai; Nikus, Kjell; Kligfield, Paul; Fiol, Miguel; Barrabés, Jose Antonio; Sionis, Alessandro; Pahlm, Olle; Niebla, J Garcia; de Luna, Antonio Bayès

    2014-09-01

    The electrocardiogram (ECG) is the most widely used imaging tool helping in diagnosis and initial management of patients presenting with symptoms compatible with acute coronary syndrome. Acute ischemia affects the configuration of the QRS complexes, the ST segments and the T waves. The ECG should be read along with the clinical assessment of the patient. ST segment elevation (and ST depression in leads V1 -V3 ) in patients with active symptoms usually indicates acute occlusion of an epicardial artery with ongoing transmural ischemia. These patients should be triaged for emergent reperfusion therapy per current guidelines. However, many patients have ST segment elevation secondary to nonischemic causes. ST depression in leads other than V1 -V3 usually are indicative of subendocardial ischemia secondary to subocclusion of the epicardial artery, distal embolization to small arteries or spasm supply/demand mismatch. ST depression may also be secondary to nonischemic etiologies, such as left ventricular hypertrophy, cardiomyopathies, etc. Knowing the clinical scenario, comparison to previous ECG and subsequent ECGs (in cases that there are changes in the quality or severity of symptoms) may add in the diagnosis and interpretation in difficult cases. This review addresses the different ECG patterns, typically seen in patients with active symptoms, after resolution of symptoms and the significance of such changes when seen in asymptomatic patients.

  9. On ECG reconstruction using weighted-compressive sensing.

    Science.gov (United States)

    Zonoobi, Dornoosh; Kassim, Ashraf A

    2014-06-01

    The potential of the new weighted-compressive sensing approach for efficient reconstruction of electrocardiograph (ECG) signals is investigated. This is motivated by the observation that ECG signals are hugely sparse in the frequency domain and the sparsity changes slowly over time. The underlying idea of this approach is to extract an estimated probability model for the signal of interest, and then use this model to guide the reconstruction process. The authors show that the weighted-compressive sensing approach is able to achieve reconstruction performance comparable with the current state-of-the-art discrete wavelet transform-based method, but with substantially less computational cost to enable it to be considered for use in the next generation of miniaturised wearable ECG monitoring devices.

  10. ECG compression: evaluation of FFT, DCT, and WT performance.

    Science.gov (United States)

    GholamHosseini, H; Nazeran, H; Moran, B

    1998-12-01

    This work investigates a set of ECG data compression schemes to compare their performances in compressing and preparing ECG signals for automatic cardiac arrhythmia classification. These schemes are based on transform methods such as fast Fourier transform (FFT), discrete cosine transform (DCT), wavelet transform (WT), and their combinations. Each specific transform is applied to a pre-selected data segment from the MIT-BIH database and then compression is performed in the new domain. These transformation methods are known as an important class of ECG compression techniques. The WT has been shown as the most efficient method for further improvement. A compression ratio of 7.98 to 1 has been achieved with a percent of root mean square difference (PRD) of 0.25%, indicating that the wavelet compression technique offers the best performance over the other evaluated methods.

  11. The ECG measurement in the bathtub using the insulated electrodes.

    Science.gov (United States)

    Lim, Yong Kyu; Kim, Ko Keun; Park, Kwang Suk

    2004-01-01

    The ECG recording in the bathtub was studied using insulated electrode. Prior studies of the ECG recording in the bathtub used conductive electrodes having some problems such as the possibility of the electric shock and sensitivity to contamination of the electrode surfaces. The insulated electrodes were made of copper plate coated with PET film. The electrodes were attached on bathtub at both sides of the chest. High-input-impedance amplifier was designed to amplify ECG signal sensed by insulated electrodes of high impedance. The recorded signals in this study were noisier than those recorded with conventional conductive electrodes. But the R peaks in the recorded signals were large enough to be auto-detected. Further study will improve SNR by reducing of power line noise and common-mode noise.

  12. Chaos control applied to cardiac rhythms represented by ECG signals

    Science.gov (United States)

    Borem Ferreira, Bianca; Amorim Savi, Marcelo; Souza de Paula, Aline

    2014-10-01

    The control of irregular or chaotic heartbeats is a key issue in cardiology. In this regard, chaos control techniques represent a good alternative since they suggest treatments different from those traditionally used. This paper deals with the application of the extended time-delayed feedback control method to stabilize pathological chaotic heart rhythms. Electrocardiogram (ECG) signals are employed to represent the cardiovascular behavior. A mathematical model is employed to generate ECG signals using three modified Van der Pol oscillators connected with time delay couplings. This model provides results that qualitatively capture the general behavior of the heart. Controlled ECG signals show the ability of the strategy either to control or to suppress the chaotic heart dynamics generating less-critical behaviors.

  13. 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).

  14. ECG Holter monitor with alert system and mobile application

    Science.gov (United States)

    Teron, Abigail C.; Rivera, Pedro A.; Goenaga, Miguel A.

    2016-05-01

    This paper proposes a new approach on the Holter monitor by creating a portable Electrocardiogram (ECG) Holter monitor that will alert the user by detecting abnormal heart beats using a digital signal processing software. The alarm will be triggered when the patient experiences arrhythmias such as bradycardia and tachycardia. The equipment is simple, comfortable and small in size that fit in the hand. It can be used at any time and any moment by placing three leads to the person's chest which is connected to an electronic circuit. The ECG data will be transmitted via Bluetooth to the memory of a selected mobile phone using an application that will store the collected data for up to 24 hrs. The arrhythmia is identified by comparing the reference signals with the user's signal. The diagnostic results demonstrate that the ECG Holter monitor alerts the user when an arrhythmia is detected thru the Holter monitor and mobile application.

  15. Lyapunov exponents for synchronous 12-lead ECG signals

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The Lyapunov exponents of synchronous 12-lead ECG signals have been investigated for the first time using a multi-sensor (electrode) technique. The results show that the Lyapunov exponents computed from different locations on the body surface are not the same, but have a distribution characteristic for the ECG signals recorded from coronary artery disease (CAD) patients with sinus rhythms and for signals from healthy older people. The maximum Lyapunov exponent L1 of all signals is positive. While all the others are negative, so the ECG signal has chaotic characteristics. With the same leads, L1 of CAD patients is less than that of healthy people, so the CAD patients and healthy people can be classified by L1, L1 therefore has potential values in the diagnosis of heart disease.

  16. 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....

  17. Hemodynamic, ventilator, and ECG changes in pediatric patients undergoing extraction

    Directory of Open Access Journals (Sweden)

    Y K Sanadhya

    2013-01-01

    Full Text Available Background: Dental treatment induces pain anxiety and fear. This study was conducted to assess the changes in hemodynamic, ventilator, and electrocardiograph changes during extraction procedure among 12-15-year-old children and compare these changes with anxiety, fear, and pain. Materials and Methods: A purposive sample of 60 patients selected based on inclusion and exclusion criteria underwent study procedure in the dental OPD of a medical college and hospital. The anxiety, fear, and pain were recorded by dental anxiety scale, dental fear scale, and visual analogue scale, respectively, before the start of the procedure. The systolic blood pressure, diastolic blood pressure, heart rate, oxygen saturation, and electrocardiogram changes were monitored during the extraction procedure. The recording was taken four times (preinjection phase, injection, extraction, and postextraction and was analyzed. Results: At the preinjection phase the mean vales were systolic blood pressure (128 ± 11.2, diastolic blood pressure (85.7 ± 6.3, heart rate (79.7 ± 9.3, and oxygen saturation (97.9 ± 5.8. These values increased in injection phases and decreased in extraction phase and the least values were found after 10 min of procedure and this relation was significant for all parameters except oxygen saturation (P = 0.48, NS. ECG abnormalities were seen among 22 patients and were significant before and after injection of Local anesthetic (P = 0.0001, S. Conclusions: Anxiety, fear, and pain have an effect on hemodynamic, ventilator, and cardiovascular parameters during the extraction procedure and hence behavioral management has to be emphasized among children in dental clinics.

  18. Adaptive filtering for ECG rejection from surface EMG recordings.

    Science.gov (United States)

    Marque, C; Bisch, C; Dantas, R; Elayoubi, S; Brosse, V; Pérot, C

    2005-06-01

    Surface electromyograms (EMG) of back muscles are often corrupted by electrocardiogram (ECG) signals. This noise in the EMG signals does not allow to appreciate correctly the spectral content of the EMG signals and to follow its evolution during, for example, a fatigue process. Several methods have been proposed to reject the ECG noise from EMG recordings, but seldom taking into account the eventual changes in ECG characteristics during the experiment. In this paper we propose an adaptive filtering algorithm specifically developed for the rejection of the electrocardiogram corrupting surface electromyograms (SEMG). The first step of the study was to choose the ECG electrode position in order to record the ECG with a shape similar to that found in the noised SEMGs. Then, the efficiency of different algorithms were tested on 28 erector spinae SEMG recordings. The best algorithm belongs to the fast recursive least square family (FRLS). More precisely, the best results were obtained with the simplified formulation of a FRLS algorithm. As an application of the adaptive filtering, the paper compares the evolutions of spectral parameters of noised or denoised (after adaptive filtering) surface EMGs recorded on erector spinae muscles during a trunk extension. The fatigue test was analyzed on 16 EMG recordings. After adaptive filtering, mean initial values of energy and of mean power frequency (MPF) were significantly lower and higher respectively. The differences corresponded to the removal of the ECG components. Furthermore, classical fatigue criteria (increase in energy and decrease in MPF values over time during the fatigue test) were better observed on the denoised EMGs. The mean values of the slopes of the energy-time and MPF-time linear relationships differed significantly when established before and after adaptive filtering. These results account for the efficacy of the adaptive filtering method proposed here to denoise electrophysiological signals.

  19. Fault Tolerant Neural Network for ECG Signal Classification Systems

    Directory of Open Access Journals (Sweden)

    MERAH, M.

    2011-08-01

    Full Text Available The aim of this paper is to apply a new robust hardware Artificial Neural Network (ANN for ECG classification systems. This ANN includes a penalization criterion which makes the performances in terms of robustness. Specifically, in this method, the ANN weights are normalized using the auto-prune method. Simulations performed on the MIT ? BIH ECG signals, have shown that significant robustness improvements are obtained regarding potential hardware artificial neuron failures. Moreover, we show that the proposed design achieves better generalization performances, compared to the standard back-propagation algorithm.

  20. Left bundle branch block: a rare ECG manifestation of hyperkalemia

    Directory of Open Access Journals (Sweden)

    Venkata Madhav M

    2015-04-01

    Full Text Available A 20-year-old female patient with chronic kidney disease was brought to our emergency medical department with symptoms of pain in chest and abdomen, vomitings. Laboratory testing revealed serum potassium 7.7 mEq/L, serum creatinine 9.1 mg/dL. Electrocardiogram (ECG showed left bundle branch block (LBBB pattern with left axis deviation, tall T waves and ST elevation. Among ECG alterations in hyperkalemia, LBBB is rare and is being reported in our case.

  1. 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.

  2. 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.

  3. Antiequine chorionic gonadotropin (eCG) antibodies generated in goats treated with eCG for the induction of ovulation modulate the luteinizing hormone and follicle-stimulating hormone bioactivities of eCG differently.

    Science.gov (United States)

    Hervé, Virginie; Roy, François; Bertin, Jean; Guillou, Florian; Maurel, Marie-Christine

    2004-01-01

    In dairy goats, treatments associating a progestogen and the equine chorionic gonadotropin (eCG) are the easiest way to induce and synchronize estrus and ovulation and to permit artificial insemination (AI) and/or out of season breeding. From the first treatment, the injection of eCG induces, in some females, the production of anti-eCG antibodies (Abs) that will interfere with the effectiveness of subsequent treatments. These anti-eCG Abs delay the preovulatory LH surge and the ovulation time, leading to poor fertility of the treated females. In this study, by in vitro bioassays, we show that anti-eCG Abs can positively or negatively modulate the LH and/or FSH bioactivities of eCG. Moreover, the modulation level of eCG bioactivity does not depend on the anti-eCG Ab affinity for eCG, as shown by surface plasmon resonance technology. The specificity of anti-eCG Abs tested by competitive ELISA highlighted the importance of a glycan environment in the recognition mechanism, especially the sialic acids specific to eCG. The different effects of anti-eCG Abs on eCG bioactivities could be explained by two hypotheses. First, steric hindrance preventing the interaction of eCG with its receptors would explain the inhibitory effect of some anti-eCG Abs; second, a conformational change in eCG by anti-eCG Abs could induce inhibition or potentiation of eCG bioactivities. It is significant that these modulations of eCG bioactivities by anti-eCG Abs impact mainly on the FSH bioactivity of eCG, which is essential for ovarian stimulation and subsequent fertility after treatment and AI, and to a lesser extent on LH bioactivity.

  4. Reliability of an external loop recorder for automatic recognition and transtelephonic ECG transmission of atrial fibrillation.

    Science.gov (United States)

    Müller, Axel; Scharner, Wilfried; Borchardt, Tilo; Och, Wolfgang; Korb, Harald

    2009-01-01

    In order to test a newly developed algorithm for detecting atrial fibrillation in clinical practice, we carried out parallel recordings using a conventional 24-h electrocardiogram (ECG) monitor and telemonitoring with an external loop recorder. Recordings were made in 24 patients with persistent atrial fibrillation and in another 24 patients with sinus rhythm. Atrial fibrillation was detected immediately in 23 of 24 patients with persistent atrial fibrillation and 20 min after fitting the single-channel loop recorder in the 24th patient (sensitivity 100%). On average, 3.1 false positives (i.e. detection of an episode, including the end or beginning of atrial fibrillation) were transmitted per patient. The sensitivity of the algorithms for automatically detecting bradycardiac and tachycardiac atrial fibrillation was also high. In 12 of 24 patients with sinus rhythm, false-positive tele-ECGs were transmitted. These were caused by supraventricular or ventricular extrasystoles and by sinus arrhythmias or sinoatrial (SA) blocks. The external loop recorder was very effective at detecting paroxysmal atrial fibrillation. Possible indications for the clinical use of this recorder include, in addition to diagnosis, monitoring patients for atrial fibrillation recurrence after cardioversion or catheter ablation.

  5. Robust and accurate anomaly detection in ECG artifacts using time series motif discovery.

    Science.gov (United States)

    Sivaraks, Haemwaan; Ratanamahatana, Chotirat Ann

    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.

  6. 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…

  7. Diagnostic quality of time-averaged ECG-gated CT data

    NARCIS (Netherlands)

    Klein, A.; Oostveen, L.J.; Greuter, M.J.W.; Hoogeveen, Y.; Schultze Kool, L.J.; Slump, C.H.; Renema, W.K.J.; Samei, Ehsan; Hsieh, Jiang

    2009-01-01

    Purpose: ECG-gated CTA allows visualization of the aneurysm and stentgraft during the different phases of the cardiac cycle, although with a lower SNR per cardiac phase than without ECG gating using the same dose. In our institution, abdominal aortic aneurysm (AAA) is evaluated using non-ECG-gated C

  8. 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…

  9. Using Intracardiac Vectorcardiographic Loop for Surface ECG Synthesis

    Directory of Open Access Journals (Sweden)

    G. Carrault

    2008-09-01

    Full Text Available Current cardiac implantable devices offer improved processing power and recording capabilities. Some of these devices already provide basic telemonitoring features that may help to reduce health care expenditure. A challenge is posed in particular for the telemonitoring of the patient's cardiac electrical activity. Indeed, only intracardiac electrograms (EGMs are acquired by the implanted device and these signals are difficult to analyze directly by clinicians. In this paper, we propose a patient-specific method to synthesize the surface electrocardiogram (ECG from a set of EGM signals, based on a 3D representation of the cardiac electrical activity and principal component analysis (PCA. The results, in the case of sinus rhythm, show a correlation coefficient between the real ECG and the synthesized ECG of about 0.85. Moreover, the application of the proposed method to the patients who present an abnormal heart rhythm exhibits promising results, especially for characterizing the bundle branch blocs. Finally, in order to evaluate the behavior of our procedure in some practical situations, the quality of the ECG reconstruction is studied as a function of the number of EGM electrodes provided by the CIDs.

  10. ECG-based heartbeat classification for arrhythmia detection: A survey.

    Science.gov (United States)

    Luz, Eduardo José da S; Schwartz, William Robson; Cámara-Chávez, Guillermo; Menotti, David

    2016-04-01

    An electrocardiogram (ECG) measures the electric activity of the heart and has been widely used for detecting heart diseases due to its simplicity and non-invasive nature. By analyzing the electrical signal of each heartbeat, i.e., the combination of action impulse waveforms produced by different specialized cardiac tissues found in the heart, it is possible to detect some of its abnormalities. In the last decades, several works were developed to produce automatic ECG-based heartbeat classification methods. In this work, we survey the current state-of-the-art methods of ECG-based automated abnormalities heartbeat classification by presenting the ECG signal preprocessing, the heartbeat segmentation techniques, the feature description methods and the learning algorithms used. In addition, we describe some of the databases used for evaluation of methods indicated by a well-known standard developed by the Association for the Advancement of Medical Instrumentation (AAMI) and described in ANSI/AAMI EC57:1998/(R)2008 (ANSI/AAMI, 2008). Finally, we discuss limitations and drawbacks of the methods in the literature presenting concluding remarks and future challenges, and also we propose an evaluation process workflow to guide authors in future works.

  11. Disease Classification and Biomarker Discovery Using ECG Data

    Directory of Open Access Journals (Sweden)

    Rong Huang

    2015-01-01

    Full Text Available In the recent decade, disease classification and biomarker discovery have become increasingly important in modern biological and medical research. ECGs are comparatively low-cost and noninvasive in screening and diagnosing heart diseases. With the development of personal ECG monitors, large amounts of ECGs are recorded and stored; therefore, fast and efficient algorithms are called for to analyze the data and make diagnosis. In this paper, an efficient and easy-to-interpret procedure of cardiac disease classification is developed through novel feature extraction methods and comparison of classifiers. Motivated by the observation that the distributions of various measures on ECGs of the diseased group are often skewed, heavy-tailed, or multimodal, we characterize the distributions by sample quantiles which outperform sample means. Three classifiers are compared in application both to all features and to dimension-reduced features by PCA: stepwise discriminant analysis (SDA, SVM, and LASSO logistic regression. It is found that SDA applied to dimension-reduced features by PCA is the most stable and effective procedure, with sensitivity, specificity, and accuracy being 89.68%, 84.62%, and 88.52%, respectively.

  12. ECG baseline wander reduction using linear phase filters

    NARCIS (Netherlands)

    Alsté, van J.A.; Eck, van W.; Hermann, O.E.

    1986-01-01

    The continuous real time reduction of baseline wander is a considerable problem in electrocardiography during exercises. Our solution consists of spectral filtering. The legitimacy of high-pass filtering of the ECG by means of digital linear phase filters with a low cut-off frequency as high as the

  13. 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.

  14. [Fetal ECG monitoring system based on MCU processing].

    Science.gov (United States)

    Hu, Gang; Chen, Wei; Xie, Xicheng; Zhang, Hao

    2004-12-01

    In order to monitor the fetus in labor, the signal characteristic from fetal scalp electrode is researched, An adaptation algorithm and a peak to peak detecting technology are adopted in signal processing, and an adaptation gain control method is used to eliminate disturber from base-line shift. A fetal ECG monitoring system is designed on the basis of C8051F020 MCU.

  15. 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.

  16. 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 deviat

  17. ECG Monitoring in Cardiac Rehabilitation: Is It Needed?

    Science.gov (United States)

    Greenland, Philip; Pomilla, Paul V.

    1989-01-01

    Discusses the controversial use of continuous electrocardiogram (ECG) monitoring as a safety measure in cardiac rehabilitation exercise programs. Little evidence substantiates its value for all patients during exercise. In the absence of empirical evidence documenting the worth of this expensive procedure, it is recommended for use with high-risk…

  18. Confidential Data Hiding Using Wavlet Based Ecg Stegnography

    Directory of Open Access Journals (Sweden)

    Malashree K S

    2014-05-01

    Full Text Available With the growing number of aging population and a significant portion of that suffering from cardiac diseases, it is conceivable that remote ECG patient monitoring systems are expected to be widely used as Point-of-Care (PoC applications in hospitals around the world. Therefore, huge amount of ECG signal collected by Body Sensor Networks (BSNs from remote patients at homes will be transmitted along with other physiological readings such as blood pressure, temperature, glucose level etc. and diagnosed by those remote patient monitoring systems. It is utterly important that patient confidentiality is protected while data is being transmitted over the public network as well as when they are stored in hospital servers used by remote monitoring systems. In this project, a wavelet based steganography technique has been introduced which combines encryption and scrambling technique to protect patient confidential data. The proposed method allows ECG signal to hide its corresponding patient confidential data and other physiological information thus guaranteeing the integration between ECG and the rest.

  19. Late postoperative episodic and constant hypoxaemia and associated ECG abnormalities

    DEFF Research Database (Denmark)

    Rosenberg, J; Rasmussen, Verner; von Jessen, F

    1990-01-01

    heart rate increased 16 beat min-1 (P less than 0.001) and mean oxygen saturation (SaO2) decreased 2.6% (P less than 0.001) after operation. Episodic oxygen desaturation to less than 80% occurred in four patients before operation, but in 13 patients after operation (P less than 0.05). ECG abnormalities...

  20. Value of Automated ECG Interpretation in Diagnosis of Cardiac Disorders

    Directory of Open Access Journals (Sweden)

    Afsaneh Mohammadi

    2008-07-01

    Full Text Available Background: Electrocardiography (ECG is a valuable device in the assessment of cardiovascular diseases. Recent medical software developments such as the invention of modern automated ECG interpreters have greatly facilitated the work of electrocardiographers and cardiologists. We present our experience in the use of one such device in the routine reporting of 200 successive ECGs recorded in our Cardiac Care Unit and Cardiac Emergency Ward. Methods: The interpretations of 200 ECGs provided by the GE-digital ECG device were chosen and compared with those supplied by four cardiologists in a single blind manner. All statistical analyses were performed by using SPSS version 11.5 for windows. A p value of less than 0.05 was considered statistically significant.Results: There was a diagnostic match between the interpretations by the device and those by the cardiologists in 107 (53.5% cases as opposed to a diagnostic mismatch in 93 cases (46.5%. The matching rate in the interpretations of myocardial ischemic disorders was high, which means practically all the ischemic cases diagnosed by the device were confirmed by the cardiologists. Only in 12 cases myocardial infarction or ischemic changes were reported by the cardiologists, while they were missed by the device. As regards rhythm disorders, the sensitivity and specificity of the device were 67.7% and 75.7%, respectively. With respect to conductive disorders, the respective sensitivity and specificity of the device were 70% and 96.6%, respectively. Finally, in the case of structural disorders, the interpretations of the device were 92.8% sensitive and 83.3% specific.Conclusion: According to the results of our study and similar researches, it seems that the interpretations of an automated ECG device in diagnosing the ischemic and structural disorders of the heart are reliable. The device, however, should not be relied upon when assessing conduction disorders and dysrhythmias. We, therefore, recommend

  1. Noninvasive ECG as a tool for predicting termination of paroxysmal atrial fibrillation.

    Science.gov (United States)

    Chiarugi, Franco; Varanini, Maurizio; Cantini, Federico; Conforti, Fabrizio; Vrouchos, Giorgos

    2007-08-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia and entails an increased risk of thromboembolic events. Prediction of the termination of an AF episode, based on noninvasive techniques, can benefit patients, doctors and health systems. The method described in this paper is based on two-lead surface electrocardiograms (ECGs): 1-min ECG recordings of AF episodes including N-type (not terminating within an hour after the end of the record), S-type (terminating 1 min after the end of the record) and T-type (terminating immediately after the end of the record). These records are organised into three learning sets (N, S and T) and two test sets (A and B). Starting from these ECGs, the atrial and ventricular activities were separated using beat classification and class averaged beat subtraction, followed by the evaluation of seven parameters representing atrial or ventricular activity. Stepwise discriminant analysis selected the set including dominant atrial frequency (DAF, index of atrial activity) and average HR (HRmean, index of ventricular activity) as optimal for discrimination between N/T-type episodes. The linear classifier, estimated on the 20 cases of the N and T learning sets, provided a performance of 90% on the 30 cases of a test set for the N/T-type discrimination. The same classifier led to correct classification in 89% of the 46 cases for N/S-type discrimination. The method has shown good results and seems to be suitable for clinical application, although a larger dataset would be very useful for improvement and validation of the algorithms and the development of an earlier predictor of paroxysmal AF spontaneous termination time.

  2. Noninvasive quantification of blood potassium concentration from ECG in hemodialysis patients

    Science.gov (United States)

    Corsi, Cristiana; Cortesi, Marilisa; Callisesi, Giulia; De Bie, Johan; Napolitano, Carlo; Santoro, Antonio; Mortara, David; Severi, Stefano

    2017-01-01

    Blood potassium concentration ([K+]) influences the electrocardiogram (ECG), particularly T-wave morphology. We developed a new method to quantify [K+] from T-wave analysis and tested its clinical applicability on data from dialysis patients, in whom [K+] varies significantly during the therapy. To elucidate the mechanism linking [K+] and T-wave, we also analysed data from long QT syndrome type 2 (LQT2) patients, testing the hypothesis that our method would have underestimated [K+] in these patients. Moreover, a computational model was used to explore the physiological processes underlying our estimator at the cellular level. We analysed 12-lead ECGs from 45 haemodialysis and 12 LQT2 patients. T-wave amplitude and downslope were calculated from the first two eigenleads. The T-wave slope-to-amplitude ratio (TS/A) was used as starting point for an ECG-based [K+] estimate (KECG). Leave-one-out cross-validation was performed. Agreement between KECG and reference [K+] from blood samples was promising (error: −0.09 ± 0.59 mM, absolute error: 0.46 ± 0.39 mM). The analysis on LQT2 patients, also supported by the outcome of computational analysis, reinforces our interpretation that, at the cellular level, delayed-rectifier potassium current is a main contributor of KECG correlation to blood [K+]. Following a comprehensive validation, this method could be effectively applied to monitor patients at risk for hyper/hypokalemia. PMID:28198403

  3. An integrated bioimpedance—ECG gating technique for respiratory and cardiac motion compensation in cardiac PET

    Science.gov (United States)

    Koivumäki, Tuomas; Nekolla, Stephan G.; Fürst, Sebastian; Loher, Simone; Vauhkonen, Marko; Schwaiger, Markus; Hakulinen, Mikko A.

    2014-10-01

    Respiratory motion may degrade image quality in cardiac PET imaging. Since cardiac PET studies often involve cardiac gating by ECG, a separate respiratory monitoring system is required increasing the logistic complexity of the examination, in case respiratory gating is also needed. Thus, we investigated the simultaneous acquisition of both respiratory and cardiac gating signals using II limb lead mimicking electrode configuration during cardiac PET scans of 11 patients. In addition to conventional static and ECG-gated images, bioimpedance technique was utilized to generate respiratory- and dual-gated images. The ability of the bioimpedance technique to monitor intrathoracic respiratory motion was assessed estimating cardiac displacement between end-inspiration and -expiration. The relevance of dual gating was evaluated in left ventricular volume and myocardial wall thickness measurements. An average 7.6  ±  3.3 mm respiratory motion was observed in the study population. Dual gating showed a small but significant increase (4 ml, p = 0.042) in left ventricular myocardial volume compared to plain cardiac gating. In addition, a thinner myocardial wall was observed in dual-gated images (9.3  ±  1.3 mm) compared to cardiac-gated images (11.3  ±  1.3 mm, p = 0.003). This study shows the feasibility of bioimpedance measurements for dual gating in a clinical setting. The method enables simultaneous acquisition of respiratory and cardiac gating signals using a single device with standard ECG electrodes.

  4. Mapping the ECG in the live rabbit heart using Ultrasound Current Source Density Imaging with coded excitation.

    Science.gov (United States)

    Qin, Yexian; Li, Qian; Ingram, Pier; Witte, Russell S

    2012-10-01

    Ultrasound current source density imaging (UCSDI) is a noninvasive technique for mapping electric current fields in 4D (space + time) with the resolution of ultrasound imaging. This approach can potentially overcome limitations of conventional electrical mapping procedures often used during treatment of cardiac arrhythmia or epilepsy. However, at physiologic currents, the detected acoustoelectric (AE) interaction signal in tissue is very weak. In this work, we evaluated coded ultrasound excitation (chirps) for improving the sensitivity of UCSDI for mapping the electrocardiogram (ECG) in a live rabbit heart preparation. Results confirmed that chirps improved detection of the AE signal by as much as 6.1 dB compared to a square pulse. We further demonstrated mapping the ECG using a clinical intracardiac catheter, 1 MHz ultrasound transducer and coded excitation. B-mode pulse echo and UCSDI revealed regions of high current flow in the heart wall during the peak of the ECG. These improvements to UCSDI are important steps towards translation of this new technology to the clinic for rapidly mapping the cardiac activation wave.

  5. Brugada phenocopy in a patient with pectus excavatum: systematic review of the ECG manifestations associated with pectus excavatum.

    Science.gov (United States)

    Awad, Sara F M; Barbosa-Barros, Raimundo; Belem, Lucia de Sousa; Cavalcante, Camila Pinto; Riera, Andrés Ricardo Pérez; Garcia-Niebla, Javier; Anselm, Daniel D; Baranchuk, Adrian

    2013-09-01

    Brugada phenocopies (BrP) have emerged as new clinical entities that are etiologically distinct from true Brugada syndrome (BrS). BrP are characterized by an ECG pattern that is phenotypically identical to true BrS (type 1 or type 2); however, BrP are caused by various other factors such as mechanical mediastinal compression, myocardial ischemia, pericarditis, myocarditis, pulmonary embolism, and metabolic disturbances. We report a case of an electrocardiographic BrP in a patient with pectus excavatum deformity in the absence of true BrS using currently defined BrP diagnostic criteria. A systematic review of ECG manifestations associated with pectus excavatum is also discussed.

  6. ECG-Derived Respiration and Instantaneous Frequency based on the Synchrosqueezing Transform: Application to Patients with Atrial Fibrillation

    CERN Document Server

    Yi-Hsin, Chan; Shu-Shya, Hseu; Chi-Tai, Kuo; Yung-Hsin, Yeh

    2011-01-01

    The acquisition of information about respiratory patterns without directly recording the respiratory signals would be beneficial in many clinical settings. The electrocardiogram (ECG)-derived respiration (EDR) algorithm, which derives the respiratory pattern by using the information encoded in ECG signals, enables data acquisition in this manner. However, the traditional EDR algorithm cannot be used in patients with atrial fibrillation (AF) because they have highly irregular heart rates. In this paper, we first provide a definition of ideal instantaneous frequency (IIF) of respiratory signals and then describe how a novel time-frequency representation technique referred to as the Synchrosqueezing transform (SST) was used for the accurate estimation of the IIF of respiratory signals, i.e., SST-IF. Then, we introduce a new EDR algorithm based on the evaluation of the SST-IF. We tested the applicability of our new EDR algorithm in patients with comorbid cardiovascular diseases, most of which were complicated by ...

  7. [Design of portable 12-lead digital ECG with low power consumption].

    Science.gov (United States)

    Sheng, Chuanguang; Yang, Cuiwei; Wu, Xiaomei; Wang, Yuanyuan; Qin, Yajie

    2013-11-01

    The design of portable and low power consumption 12-lead ECG is based on the digital signal processor TMS320C5515 and the analog front end ADS1298. The ADS1298 collects the ECG signals and deliver them to TMS320C5515. The preprocessed ECG signals are displayed real-time on a LCD and can be stored without compression for a long time. The ECG signals can also be sent to an up computer by a USB connector so that ECG data can be analyzed offline. The system has small volume, high precision and low power consumption.

  8. 动态与常规心电图诊断冠心病的对比分析%Comparative Analysis on Dynamic ECG and Routine ECG in Diagnosis of Coronary Heart Disease

    Institute of Scientific and Technical Information of China (English)

    张平

    2015-01-01

    目的:探讨动态与常规心电图诊断冠心病的对比分析。方法选取2013年11月到2014年11月我院接诊的43例冠心病患者,按照入院的先后顺序分为两组,实验组23例和对照组20例,实验组采用动态心电图法,对照组采用常规心电图组,观察两组患者的诊断结果。结果实验组患者的心肌缺血阳性检出率、心律失常检测结果明显高于对照组,差异显著,有统计学意义(P<0.05)。结论动态心电图诊断冠心病的检出率高,可以有效提高心肌缺血和心律失常的诊断率,更好地进行针对性的治疗,值得临床推广。%Objective Comparative analysis on dynamic ECG and routine ECG in diagnosis of coronary heart disease is to be comparatively studied. Methods Choose 43 patients of coronary heart disease who are received and treated in hospital from November 2013 to November 2014 and separate them into two groups according to their hospitalization sequence with 23 patients in study group and 20 patients in control group;patients in study group are given dynamic ECG diagnosis;while patients in control group are given routine ECG diagnosis,and then observe and compare diagnosis results between two groups. Results Patients’positive detection rate of myocardial ischemia as wel as their arrhythmia detection rate in study group are much higher than counterparts in control group; there is a treatment differential between two groups,and such a differential has statistic value(P<0.05).Conclusion Dynamic ECG is of efficacy in diagnosis of coronary heart disease;it is conducive to increasing patients’positive detection rate of myocardial ischemia as wel as their arrhythmia detection rate,which is significant to cure patients with targeted treatment;thus,dynamic ECG diagnosis is quite worthwhile to be promoted and applied clinical y.

  9. Screening For Atrial Fibrillation In The Community Using A Novel ECG Recorder.

    Science.gov (United States)

    Battipaglia Md, Irma; Gilbert BSc, Katrina; Hogarth Md PhD, Andrew J; Tayebjee Md, Muzahir H

    2016-01-01

    Aims: MyDiagnostick (MDK) is a novel portable ECG recorder. We conducted this study to evaluate its role in screening for atrial fibrillation (AF). Methods: The device is a cylindrical rod with metallic electrodes at both ends recording electrocardiogram (ECG) when both electrodes are held. Individuals were requested to hold the device for approximately 15 s, the device was then connected to a laptop (with proprietary software downloaded) and analysed. Anonymised ECGs were stored for further analysis. A total of 855 ECGs were recorded and analysed offline by two arrhythmia specialists assessing ECG quality, in particular the level of noise. A noise score (NS) was devised regarding ECG quality. Results: Seven individuals were found with unknown AF (0,8%). In general ECG quality was good and rhythm diagnosis was certain with total interobserver agreement. Conclusion: The MDK provided a rapid and accurate rhythm analysis and has potential implications in preventing ischaemic cardio-embolic stroke.

  10. A model presented for classification ECG signals base on Case-Based Reasoning

    Directory of Open Access Journals (Sweden)

    Elaheh Sayari

    2013-07-01

    Full Text Available Early detection of heart diseases/abnormalities can prolong life and enhance the quality of living through appropriate treatment; thus classifying cardiac signals will be helped to immediate diagnosing of heart beat type in cardiac patients. The present paper utilizes the case base reasoning (CBR for classification of ECG signals. Four types of ECG beats (normal beat, congestive heart failure beat, ventricular tachyarrhythmia beat and atrial fibrillation beat obtained from the PhysioBank database was classified by the proposed CBR model. The main purpose of this article is classifying heart signals and diagnosing the type of heart beat in cardiac patients that in proposed CBR (Case Base Reasoning system, Training and testing data for diagnosing and classifying types of heart beat have been used. The evaluation results from the model are shown that the proposed model has high accuracy in classifying heart signals and helps to clinical decisions for diagnosing the type of heart beat in cardiac patients which indeed has high impact on diagnosing the type of heart beat aided computer.

  11. An extensive Markov system for ECG exact coding.

    Science.gov (United States)

    Tai, S C

    1995-02-01

    In this paper, an extensive Markov process, which considers both the coding redundancy and the intersample redundancy, is presented to measure the entropy value of an ECG signal more accurately. It utilizes the intersample correlations by predicting the incoming n samples based on the previous m samples which constitute an extensive Markov process state. Theories of the extensive Markov process and conventional n repeated applications of m-th order Markov process are studied first in this paper. After that, they are realized for ECG exact coding. Results show that a better performance can be achieved by our system. The average code length for the extensive Markov system on the second difference signals was 2.512 b/sample, while the average Huffman code length for the second difference signals was 3.326 b/sample.

  12. [Changes in ECG examination of patients with trichinosis].

    Science.gov (United States)

    Siwak, E; Droń, D; Pancewicz, S; Zajkowska, J; Snarska, I; Szpakowicz, T; Januszkiewicz, E

    1994-07-01

    In the years 1963-1992, 560 patients with the diagnosis of trichinosis were treated in the Department of Parasitic Diseases and Neuroinfections, including 310 women (55.3%) and 250 men (44.7%) aged from 6 to 75 years. Out of this number of patients in 59 cases (10.5%) myocardial damage was found in the course of the disease. The most frequently found changes in ECG record were ventricular repolarization disturbances (66.1%) which persisted in 18.6% of cases before discharge from the hospital. Depolarization disturbances accounted for 32.2% of cases and persisted before discharge from the hospital in 10.1% of patients. In 6.7% of patients, persistence of pathological ECG record was found during the 4th month after the hospitalization which may be an evidence of prolongation of the inflammatory process within the myocardium.

  13. ECG contamination of EEG signals: effect on entropy.

    Science.gov (United States)

    Chakrabarti, Dhritiman; Bansal, Sonia

    2016-02-01

    Entropy™ is a proprietary algorithm which uses spectral entropy analysis of electroencephalographic (EEG) signals to produce indices which are used as a measure of depth of hypnosis. We describe a report of electrocardiographic (ECG) contamination of EEG signals leading to fluctuating erroneous Entropy values. An explanation is provided for mechanism behind this observation by describing the spread of ECG signals in head and neck and its influence on EEG/Entropy by correlating the observation with the published Entropy algorithm. While the Entropy algorithm has been well conceived, there are still instances in which it can produce erroneous values. Such erroneous values and their cause may be identified by close scrutiny of the EEG waveform if Entropy values seem out of sync with that expected at given anaesthetic levels.

  14. Wavelet transform based ECG signal filtering implemented on FPGA

    Directory of Open Access Journals (Sweden)

    Germán-Salló Zoltán

    2011-12-01

    Full Text Available Filtering electrocardiographic (ECG signals is always a challenge because the accuracy of their interpretation depends strongly on filtering results. The Discrete Wavelet Transform (DWT is an efficient, new and useful tool for signal processing applications and it’s adopted in many domains as biomedical signal filtering. This transform came about from different fields, including mathematics, physics and signal processing, it has a growing applicability due to its so-called multiresolution analyzing capabilities. FPGAs are reconfigurable logic devices made up of arrays of logic cells and routing channels having some specific characteristics which allow to use them in signal processing applications. This paper presents a DWT based ECG signal denoising method implemented on FPGA, using Matlab specific Xilinx tool, as System Generator, the procedure is simulated and evaluated through filtering specific parameters.

  15. QRS complex detection in ECG signal for wearable devices.

    Science.gov (United States)

    Arefin, M Riadh; Tavakolian, Kouhyar; Fazel-Rezai, Reza

    2015-01-01

    This paper presents QRS complex detection algorithm based on dual slope technique, which is suitable for wearable electrocardiogram (ECG) applications. For cardiac patients of different arrhythmias, ECG signals are needed to be monitored over an extensive period of time. Thus, the wearable heart monitoring system needs computationally efficient QRS detection technique with good accuracy. In this paper, a method of QRS detection based on two slopes on both sides of an R peak is presented which is computationally efficient. Based on the slopes, first, a variable measuring steepness is developed, then by introducing an adjustable R-R interval based window and adaptive thresholding techniques, depending on the number of peaks detected in such window, R peaks are detected. The algorithm was evaluated against MIT/BIH arrhythmia database and achieved 99.16% detection rate with sensitivity of 0.9935 and positive predictivity of 0.9981. The method was compared with two widely used R peaks detection algorithms.

  16. Combining Wavelet Transform and Hidden Markov Models for ECG Segmentation

    Directory of Open Access Journals (Sweden)

    Jérôme Boudy

    2007-01-01

    Full Text Available This work aims at providing new insights on the electrocardiogram (ECG segmentation problem using wavelets. The wavelet transform has been originally combined with a hidden Markov models (HMMs framework in order to carry out beat segmentation and classification. A group of five continuous wavelet functions commonly used in ECG analysis has been implemented and compared using the same framework. All experiments were realized on the QT database, which is composed of a representative number of ambulatory recordings of several individuals and is supplied with manual labels made by a physician. Our main contribution relies on the consistent set of experiments performed. Moreover, the results obtained in terms of beat segmentation and premature ventricular beat (PVC detection are comparable to others works reported in the literature, independently of the type of the wavelet. Finally, through an original concept of combining two wavelet functions in the segmentation stage, we achieve our best performances.

  17. Heart detection and diagnosis based on ECG and EPCG relationships

    Science.gov (United States)

    Phanphaisarn, W; Roeksabutr, A; Wardkein, P; Koseeyaporn, J; Yupapin, PP

    2011-01-01

    A new design of a system for preliminary detection of defective hearts is proposed which is composed of two subsystems, in which one is based on the relationship between the electrocardiogram (ECG) and phonocardiogram (PCG) signals. The relationship between both signals is determined as an impulse response (h(n)) of a system, where the decision is made based on the linear predictive coding coefficients of a heart’s impulse response. The other subsystem uses a phase space approach, in which the mean squared error between the distance vectors of the phase space of the normal heart and abnormal heart is judged by the likelihood ratio test (Λ) value, on which the decision is made. The advantage of the proposed system is that a heart’s diagnosis system based on the ECG and EPCG signals can lead to high performance heart diagnostics. PMID:22915940

  18. Enhanced real-time ECG coder for packetized telecardiology applications.

    Science.gov (United States)

    Alesanco, Alvaro; Olmos, Salvador; Istepanian, Robert S H; García, José

    2006-04-01

    A new real-time compression method for electrocardiogram (ECG) signals has been developed based on the wavelet transform approach. The method is specifically adaptable for packetized telecardiology applications. The signal is segmented into beats and a beat template is subtracted from them, producing a residual signal. Beat templates and residual signals are coded with a wavelet expansion. Compression is achieved by selecting a subset of wavelet coefficients. The number of selected coefficients depends on a threshold which has different definitions depending on the operational mode of the coder. Compression performance has been tested using a subset of ECG records from MIT-BIH Arrhythmia database. This method has been designed for real-time packetized telecardiology scenarios both in wired and wireless environments.

  19. Using ordinal partition transition networks to analyze ECG data

    Science.gov (United States)

    Kulp, Christopher W.; Chobot, Jeremy M.; Freitas, Helena R.; Sprechini, Gene D.

    2016-07-01

    Electrocardiogram (ECG) data from patients with a variety of heart conditions are studied using ordinal pattern partition networks. The ordinal pattern partition networks are formed from the ECG time series by symbolizing the data into ordinal patterns. The ordinal patterns form the nodes of the network and edges are defined through the time ordering of the ordinal patterns in the symbolized time series. A network measure, called the mean degree, is computed from each time series-generated network. In addition, the entropy and number of non-occurring ordinal patterns (NFP) is computed for each series. The distribution of mean degrees, entropies, and NFPs for each heart condition studied is compared. A statistically significant difference between healthy patients and several groups of unhealthy patients with varying heart conditions is found for the distributions of the mean degrees, unlike for any of the distributions of the entropies or NFPs.

  20. [Development of a portable dynamic state ECG based on DSP].

    Science.gov (United States)

    Song, Li; Meng, Qing-jian; Zhang, Guang-yu; Cao, Wei-fang

    2009-11-01

    The Portable dynamic state electrocardiogram collecting system is introduced by using TMS302VC5402, TLC320AD50C, liquid crystal display model, and so on. This dissertation describes the work principle of the system and uses the united algorithm based on wavelet to identify and locate the ECG characteristic waves. This system has as follows of advantages: big memory, low noise,high common mode rejection ratio, the low power consume,the long record time etc.

  1. Discussion of "Computational Electrocardiography: Revisiting Holter ECG Monitoring".

    Science.gov (United States)

    Baumgartner, Christian; Caiani, Enrico G; Dickhaus, Hartmut; Kulikowski, Casimir A; Schiecke, Karin; van Bemmel, Jan H; Witte, Herbert

    2016-08-01

    This article is part of a For-Discussion-Section of Methods of Information in Medicine about the paper "Computational Electrocardiography: Revisiting Holter ECG Monitoring" written by Thomas M. Deserno and Nikolaus Marx. It is introduced by an editorial. This article contains the combined commentaries invited to independently comment on the paper of Deserno and Marx. In subsequent issues the discussion can continue through letters to the editor.

  2. 窦性心律的20例心电图分析%ECG Analysis of 20 Cases of Sinus

    Institute of Scientific and Technical Information of China (English)

    赵鑫

    2014-01-01

    Objective Analyzing the ECG data from 20 cases of sinus in order to provide exact information for clinical diagnosis and treatment. Methods Analyzing ECG data of 20 cases of sinus to summarize diagnosis experience and methods.Results With ECG analysis,there are 8 cases diagnosed as sinus,6 cases are sinus arrhythmia and other 6 cases are sinus tachycardia.Conclusion ECG is quite precise to examine and diagnose sinus arrhythmia,which is an indispensable method of clinical inspection.%目的:对20例窦性心律心电图资料进行分析,为临床诊断和治疗提供准确的依据。方法回顾分析20例窦性心律心电图资料,总结诊断经验和方法。结果所有研究对象经心电检查分析,证实窦性心律8例,窦性心律不齐6例,窦性心律过速6例。结论心电影像检查在窦性心律失常的诊断中准确率高,是临床检查必不可缺的手段之一。

  3. Performance Comparison of Windowing Techniques for ECG Signal Enhancement

    Directory of Open Access Journals (Sweden)

    K.Sravan Kumar

    2014-12-01

    Full Text Available Electrocardiogram (ECG signal is generally corrupted by various artifacts like baseline wander, power line interference (50/60 Hz and electromyography noise and these must be removed before diagnosis. The task propounded in this article is removal of low frequency interference i.e. baseline wandering and high frequency noise i.e. electromyography in ECG signal and digital filters are implemented to delete it. The digital filters accomplished are FIR with various windowing methods as of Rectangular, Hann, Blackman, Hamming, and Kaiser. The results received are at order of 300,450,600.The signal taken of the MIT-BIH database which contains the normal and abnormal waveforms. The work has been in MATLAB where filters are implemented in FDA Tool. The result received for entire FIR filters with various windows are evaluated the waveforms, power spectrums density, signal to noise ratio (SNR and means square error (MSE of the noisy and filtered ECG signals. The filter which shows the excellent outcomes is the Kaiser Window.

  4. ECG Analysis based on Wavelet Transform and Modulus Maxima

    Directory of Open Access Journals (Sweden)

    Mourad Talbi

    2012-01-01

    Full Text Available In this paper, we have developed a new technique of P, Q, R, S and T Peaks detection using Wavelet Transform (WT and Modulus maxima. One of the commonest problems in electrocardiogram (ECG signal processing, is baseline wander removal suppression. Therefore we have removed the baseline wander in order to make easier the detection of the peaks P and T. Those peaks are detected after the QRS detection. The proposed method is based on the application of the discritized continuous wavelet transform (Mycwt used for the Bionic wavelet transform, to the ECG signal in order to detect R-peaks in the first stage and in the second stage, the Q and S peaks are detected using the R-peaks localization. Finally the Modulus maxima are used in the undecimated wavelet transform (UDWT domain in order to detect the others peaks (P, T. This detection is performed by using a varying-length window that is moving along the whole signal. For evaluating the proposed method, we have compared it to others techniques based on wavelets. In this evaluation, we have used many ECG signals taken from MIT-BIH database. The obtained results show that the proposed method outperforms a number of conventional techniques used for our evaluation.

  5. Capacitive driven-right-leg grounding in Indirect-contact ECG measurement.

    Science.gov (United States)

    Lim, Yong Gyu; Chung, Gih Sung; Park, Kwang Suk

    2010-01-01

    For the reduction of common-mode noise level in Indirect-contact ECG (IDC-ECG) measurement, a driven-right-leg grounding method was applied to the IDC-ECG. Because the IDC-ECG does not require any direct contact between the electrodes and the human skin, it is adequate for un-constraining long-term ECG measurement at home and its various applications are now under development. However, larger 60 Hz noise induced by power line appears in IDC-ECG than in conventional ECG, that is a restriction of IDC-ECG application. In this study, the driven-right-leg ground which has been used in conventional direct-contact ECG, was adapted to the IDC-ECG measurement, by feedback of the inversion of amplified common-mode noise to the body through the conductive textile laid on the chair seat. It was shown that the level of 60Hz power line noise was reduced to about -40 dB when the driven-right-leg gain was 1000.

  6. 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.

  7. Measurements on wireless transmission of ECG signals

    Science.gov (United States)

    Gabrielli, A.; Lax, I.

    2016-12-01

    The scope of this research is to design an electronic prototype, an operative system as a proof of concept, to transmit and receive biological parameters, in particular electrocardiogram signals, through dedicated wireless circuits. The apparatus features microelectronics chips that were developed for more general biomedical applications, here adapted to deal with cardiac signals. The paper mainly focuses on the electronic aspects, as in this study we do not face medical or clinical aspects of the system. The transmitter circuit uses a commercial instrumentation amplifier and the receiver has been equipped with wide-band amplifiers along with made-in-the-lab band-pass filters centered at the carrier. We have been able to mount the entire system prototype into a preliminary data acquisition chain that reads out the electrocardiogram signal. The prototype allows acquiring the waveform, converting it to a digital pattern and open the transmission through a series of high-frequency packets exploiting the Ultra Wide Band protocol. The sensor value is embedded in the transmission through the rate of the digital packets. In fact, these are sent wireless at a specific packet-frequency that depends on the sensor amplitude and are detected into a receiver circuit that recovers the information.

  8. Application of Holter ECG Signal Analysis Based on Wavelet and Data Mining Technique

    Institute of Scientific and Technical Information of China (English)

    余辉; 谢远国; 周仲兴; 吕扬生

    2004-01-01

    A new model based on dyadic differential wavelet was developed for detecting the R peak in Holter ECG signal according to the design of data mining. The Mallat recursive filter algorithm was introduced to calculate wavelet and optimize the detection algorithm which is based on the equivalent filter technique. The detection algorithm has been verified by MIT arrhythmia database with a high efficiency of 99%. After optimization,the algorithm was put into clinical experiment and tested in the Air Force Hospital in Tianjin for about two months. After about 108 hearts beating test of more than 100 patients, the total efficient detection rate has reached 97%. Now this algorithm module has been applied in business software and shows perfect performance under the complex conditions such as the inversion of heart beating, the falling off of the electrodes, the excursion of base line and so on.

  9. [Design of the Mobile ECG Monitoring System Based on Android 4.3].

    Science.gov (United States)

    Zhang, Shun; Lian, Yuxi; Qin, Yajie; Wang, Yuanyuan

    2015-07-01

    To monitor and record Electrocardiograph (ECG) signals for 24 hours, a mobile ECG monitoring system is designed based on Android 4.3. In this system, domestic indigenous E9622A is used to acquire ECG signals and TI CC2541 is adopted to communicate with mobile phones. The program is implemented on the Android platform to display and process ECG signals. The whole system is integrated on a 2 cm x 2 cm PCB. From experiments, it is shown that ECG signals can be obtained effectively when this system is worn, and clear ECG waveforms and parameters can be shown on the phones. With this system, arrhythmia can be diagnosed preliminarily. It is also shown that the system is low-power, low-cost, flexible and portable.

  10. Review Paper :Comparative Analysis Of Mother Wavelet Functions With The ECG Signals

    Directory of Open Access Journals (Sweden)

    Kapil Tajane

    2014-01-01

    Full Text Available Electrocardiographic ECG gives the information about electrical activity of the heart captured over time by attaching an external electrode to the skin. Now a days ECG signal is used as a baseline to determine the hearts condition. It is very much essential to detect and process ECG signal accurately. ECG consists of various types of noise such as muscle noise, baseline wander and power line interference etc. To remove such types of noise wavelet transform is used. Mother wavelet is an effective tool for denoising such signals. But selection of proper mother wavelet for the ECG signal is again a challenging task. This paper gives the survey about the wavelet transforms useful for ECG denoising. The different wavelet transform are compared and from that we can decide which one is more suitable.

  11. CLASSIFICATION OF ECG DATA FOR PREDICTIVE ANALYSIS TO ASSIST IN MEDICAL DECISIONS

    Directory of Open Access Journals (Sweden)

    Mrs. A. R. Chitupe

    2013-11-01

    Full Text Available In recent years due to physical and mental stress in the working environments the cases of medicaldiagnosis using ECG are increasing up-bounds. The critical decisions in diagnosis referring to the normal ECG or indicative dysfunctions of the heart results into overlapped data values causing ambiguities. This research paper performs analytical processing and related mining to classify normal and abnormalities of the ECG. The ECG is agraphical representation generated due to polarities of the weak electrical signals generated in certain defined timely manner. With reference to time an ECG is used to measure the rate and regularity of heartbeats, as well as some special behaviour of the patient. ECG can be used to investigate heart abnormalities.

  12. Reducing of gradient induced artifacts on the ECG signal during MRI examinations using Wilcoxon filter

    Directory of Open Access Journals (Sweden)

    Schmidt Marcus

    2016-09-01

    Full Text Available The electrocardiogramm (ECG is the state-of-the-art signal for gating in cardiovascular magnetic resonance imaging and patient monitoring. Using the ECG for gating and monitoring during the magnetic resonance imaging examination is a high challenging task due to the superimposition of the magnetohydrodynamic effect, radio-frequency (RF pulses and fast switching gradient magnetic fields. The gradient induced artifacts hamper the correct QRS detection which is needed for correct gating and heart rate calculation and ECG displaying for patient monitoring. To suppress the gradient artifacts from the ECG signal acquired during MRI, a technique based on the Wilcoxon filter was developed. It was evaluated using ECG signals of 14 different subjects acquired in a 3 T MRI scanner. It could be shown reliable results for reducing gradient induced artifacts in the ECG signal in real-time.

  13. The Combined Effect of Filters in ECG Signals for Pre-Processing

    Directory of Open Access Journals (Sweden)

    Isha V. Upganlawar

    2014-05-01

    Full Text Available The ECG signal is abruptly changing and continuous in nature. The heart disease such as paroxysmal of heart, arrhythmia diagnosing, are related with the intelligent health care decision this ECG signal need to be pre-process accurately for further action on it such as extracting the features, wavelet decomposition, distribution of QRS complexes in ECG recordings and related information such as heart rate and RR interval, classification of the signal by using various classifiers etc. Filters plays very important role in analyzing the low frequency components in ECG signal. The biomedical signals are of low frequency, the removal of power line interference and baseline wander is a very important step at the pre-processing stage of ECG. In these paper we deal with the study of Median filtering and FIR (Finite Impulse Responsefiltering of ECG signals under noisy condition

  14. A Novel 12-Lead ECG T-Shirt with Active Electrodes

    Directory of Open Access Journals (Sweden)

    Anna Boehm

    2016-11-01

    Full Text Available We developed an ECG T-shirt with a portable recorder for unobtrusive and long-term multichannel ECG monitoring with active electrodes. A major drawback of conventional 12-lead ECGs is the use of adhesive gel electrodes, which are uncomfortable during long-term application and may even cause skin irritations and allergic reactions. Therefore, we integrated comfortable patches of conductive textile into the ECG T-shirt in order to replace the adhesive gel electrodes. In order to prevent signal deterioration, as reported for other textile ECG systems, we attached active circuits on the outside of the T-shirt to further improve the signal quality of the dry electrodes. Finally, we validated the ECG T-shirt against a commercial Holter ECG with healthy volunteers during phases of lying down, sitting, and walking. The 12-lead ECG was successfully recorded with a resulting mean relative error of the RR intervals of 0.96% and mean coverage of 96.6%. Furthermore, the ECG waves of the 12 leads were analyzed separately and showed high accordance. The P-wave had a correlation of 0.703 for walking subjects, while the T-wave demonstrated lower correlations for all three scenarios (lying: 0.817, sitting: 0.710, walking: 0.403. The other correlations for the P, Q, R, and S-waves were all higher than 0.9. This work demonstrates that our ECG T-shirt is suitable for 12-lead ECG recordings while providing a higher level of comfort compared with a commercial Holter ECG.

  15. The Combined Effect of Filters in ECG Signals for Pre-Processing

    OpenAIRE

    Isha V. Upganlawar; Harshal Chowhan

    2014-01-01

    The ECG signal is abruptly changing and continuous in nature. The heart disease such as paroxysmal of heart, arrhythmia diagnosing, are related with the intelligent health care decision this ECG signal need to be pre-process accurately for further action on it such as extracting the features, wavelet decomposition, distribution of QRS complexes in ECG recordings and related information such as heart rate and RR interval, classification of the signal by using various classifiers etc. Filters p...

  16. A dynamic Fourier series for the compression of ECG using FFT and adaptive coefficient estimation.

    Science.gov (United States)

    al-Nashash, H A

    1995-04-01

    In this article, a new ECG data compression technique is proposed. The method relies on modelling quasi-periodic ECG signals as a dynamic Fourier series. Fourier coefficients are continuously estimated using either an FFT algorithm or the adaptive least mean square algorithm. Results from simulated normal and pathological ECGs are presented and discussed. The merits of each of the above two methods are also illustrated. Furthermore, a comparison with other compression techniques is also discussed.

  17. On the improved correlative prediction scheme for aliased electrocardiogram (ECG) data compression.

    Science.gov (United States)

    Gao, Xin

    2012-01-01

    An improved scheme for aliased electrocardiogram (ECG) data compression has been constructed, where the predictor exploits the correlative characteristics of adjacent QRS waveforms. The twin-R correlation prediction and lifting wavelet transform (LWT) for periodical ECG waves exhibits feasibility and high efficiency to achieve lower distortion rates with realizable compression ratio (CR); grey predictions via GM(1, 1) model have been adopted to evaluate the parametric performance for ECG data compression. Simulation results illuminate the validity of our approach.

  18. Economic analysis of the use of coronary calcium scoring as an alternative to stress ECG in the non-invasive diagnosis of coronary artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Raman, Vivek [Brighton and Sussex University Hospitals, Brighton (United Kingdom); Royal Sussex County Hospital, Brighton (United Kingdom); McWilliams, Eric T.M. [Conquest Hospital, Hastings (United Kingdom); Holmberg, Stephen R.M.; Miles, Ken [Brighton and Sussex University Hospitals, Brighton (United Kingdom)

    2012-03-15

    To conduct an economic analysis (EA) of coronary calcium scoring (CCS) using a 0 score, as alternative to stress electrocardiography (sECG) in diagnosing coronary artery disease (CAD). A decision tree was constructed to compare four strategies for investigation of suspected CAD previously assessed in the formulation of clinical guidelines for the United Kingdom (UK) to two new strategies incorporating CCS. Sensitivity (96%; 95% CI 95.4-96.4%) and specificity (40%; 95% CI 38.7-41.4%) values for CCS were derived from a meta-analysis of 10,760 patients. Other input variables were obtained from a previous EA and average prices for hospital procedures in the UK. A threshold of pound 30,000/Quality-adjusted Life Year (QALY) was considered cost-effective. Using net monetary benefit calculations, CCS-based strategies were found to be cost-effective compared to sECG equivalents at all assessed prevalence of CAD. Using CCS prior to myocardial perfusion scintigraphy (MPS) and catheter angiography (CA) was found to be cost-effective at pre-test probabilities (PTP) below 30%. Adoption of CCS as an alternative to sECG in investigating suspected stable angina in low PTP population (<30%) would be cost-effective. In patients with PTP of CAD >30%, proceeding to MPS or CA would be more cost-effective than performing either CCS or sECG. (orig.)

  19. A Novel Approach to ECG Classification Based upon Two-Layered HMMs in Body Sensor Networks

    Directory of Open Access Journals (Sweden)

    Wei Liang

    2014-03-01

    Full Text Available This paper presents a novel approach to ECG signal filtering and classification. Unlike the traditional techniques which aim at collecting and processing the ECG signals with the patient being still, lying in bed in hospitals, our proposed algorithm is intentionally designed for monitoring and classifying the patient’s ECG signals in the free-living environment. The patients are equipped with wearable ambulatory devices the whole day, which facilitates the real-time heart attack detection. In ECG preprocessing, an integral-coefficient-band-stop (ICBS filter is applied, which omits time-consuming floating-point computations. In addition, two-layered Hidden Markov Models (HMMs are applied to achieve ECG feature extraction and classification. The periodic ECG waveforms are segmented into ISO intervals, P subwave, QRS complex and T subwave respectively in the first HMM layer where expert-annotation assisted Baum-Welch algorithm is utilized in HMM modeling. Then the corresponding interval features are selected and applied to categorize the ECG into normal type or abnormal type (PVC, APC in the second HMM layer. For verifying the effectiveness of our algorithm on abnormal signal detection, we have developed an ECG body sensor network (BSN platform, whereby real-time ECG signals are collected, transmitted, displayed and the corresponding classification outcomes are deduced and shown on the BSN screen.

  20. Embedding patients confidential data in ECG signal for healthcare information systems.

    Science.gov (United States)

    Ibaida, Ayman; Khalil, Ibrahim; Al-Shammary, Dhiah

    2010-01-01

    In Wireless tele-cardiology applications, ECG signal is widely used to monitor cardiac activities of patients. Accordingly, in most e-health applications, ECG signals need to be combined with patient confidential information. Data hiding and watermarking techniques can play a crucial role in ECG wireless tele-monitoring systems by combining the confidential information with the ECG signal since digital ECG data is huge enough to act as host to carry tiny amount of additional secret data. In this paper, a new steganography technique is proposed that helps embed confidential information of patients into specific locations (called special range numbers) of digital ECG host signal that will cause minimal distortion to ECG, and at the same time, any secret information embedded is completely extractable. We show that there are 2.1475 × 10(9) possible special range numbers making it extremely difficult for intruders to identify locations of secret bits. Experiments show that percentage residual difference (PRD) of watermarked ECGs can be as low as 0.0247% and 0.0678% for normal and abnormal ECG segments (taken from MIT-BIH Arrhythmia database) respectively.

  1. Analysis of ECG-trunk muscle signal amplitude and heart rate relationship.

    Science.gov (United States)

    Benosman, Mourad-M; Bereksi-Reguig, Fethi; Salerud, E Göran

    2013-10-01

    The objective of this paper is to investigate if bioelectrical signals, generated from trunk muscles identified in an electrocardiogram (ECG) signal presented in this paper as ECG-Trunk Muscles Signals amplitude (Ecg-TMSA) are correlated with Heart rate (HR) during different levels of physical activity and also if Ecg-TMSA is not influenced by mental activity. HR and Ecg-TMSA were derived from ECG in 14 subjects when walking and jogging at different treadmill velocities from 4-10 (km h(-1)). The mean relationship for all 14 subjects was HR = (42.3 ± 0.2) + (45.3 ± 2.8) Ecg-TMSA, r(2 )= 0.91. The result of one individual data points example for a 21 min experiment was (r(2 )= 0.93, p Ecg-TMSA and HR. Moreover, the Ecg-TMSA was not affected by mental activity.

  2. A Low Power Linear Phase Digital FIR Filter for Wearable ECG Devices.

    Science.gov (United States)

    Lian, Yong; Yu, Jianghong

    2005-01-01

    In this paper we present a low power linear phase digital FIR filter which is a part of an ECG-on-Chip. The ECG-on-Chip can be embedded into clothing to acquire the electrocardiogram (ECG) signal and send a warning message to a mobile phone or PDA if an abnormal ECG is detected. The proposed new filter structure significantly reduces the arithmetic operations for each sample which in turn lowers the power consumption. The filter is developed based on the interpolated finite impulse filter technique and is very attractive for a low cost and low power VLSI implementation.

  3. A novel approach to ECG classification based upon two-layered HMMs in body sensor networks.

    Science.gov (United States)

    Liang, Wei; Zhang, Yinlong; Tan, Jindong; Li, Yang

    2014-03-27

    This paper presents a novel approach to ECG signal filtering and classification. Unlike the traditional techniques which aim at collecting and processing the ECG signals with the patient being still, lying in bed in hospitals, our proposed algorithm is intentionally designed for monitoring and classifying the patient's ECG signals in the free-living environment. The patients are equipped with wearable ambulatory devices the whole day, which facilitates the real-time heart attack detection. In ECG preprocessing, an integral-coefficient-band-stop (ICBS) filter is applied, which omits time-consuming floating-point computations. In addition, two-layered Hidden Markov Models (HMMs) are applied to achieve ECG feature extraction and classification. The periodic ECG waveforms are segmented into ISO intervals, P subwave, QRS complex and T subwave respectively in the first HMM layer where expert-annotation assisted Baum-Welch algorithm is utilized in HMM modeling. Then the corresponding interval features are selected and applied to categorize the ECG into normal type or abnormal type (PVC, APC) in the second HMM layer. For verifying the effectiveness of our algorithm on abnormal signal detection, we have developed an ECG body sensor network (BSN) platform, whereby real-time ECG signals are collected, transmitted, displayed and the corresponding classification outcomes are deduced and shown on the BSN screen.

  4. ECG De-noising: A comparison between EEMD-BLMS and DWT-NN algorithms.

    Science.gov (United States)

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

    2015-08-01

    Electrocardiogram (ECG) is a widely used non-invasive 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 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 their performance. These methods were first compared on two types of simulated noise corrupted ECG signals: Type-I (desired ECG+noise frequencies outside the ECG frequency band) and Type-II (ECG+noise frequencies both inside and outside the ECG frequency band). Subsequently, they were tested on real ECG recordings. Results clearly show that both the methods works equally well when used on Type-I signals. However, on Type-II signals the DWT-NN 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 artifacts.

  5. Can Functional Cardiac Age be Predicted from ECG in a Normal Healthy Population

    Science.gov (United States)

    Schlegel, Todd; Starc, Vito; Leban, Manja; Sinigoj, Petra; Vrhovec, Milos

    2011-01-01

    In a normal healthy population, we desired to determine the most age-dependent conventional and advanced ECG parameters. We hypothesized that changes in several ECG parameters might correlate with age and together reliably characterize the functional age of the heart. Methods: An initial study population of 313 apparently healthy subjects was ultimately reduced to 148 subjects (74 men, 84 women, in the range from 10 to 75 years of age) after exclusion criteria. In all subjects, ECG recordings (resting 5-minute 12-lead high frequency ECG) were evaluated via custom software programs to calculate up to 85 different conventional and advanced ECG parameters including beat-to-beat QT and RR variability, waveform complexity, and signal-averaged, high-frequency and spatial/spatiotemporal ECG parameters. The prediction of functional age was evaluated by multiple linear regression analysis using the best 5 univariate predictors. Results: Ignoring what were ultimately small differences between males and females, the functional age was found to be predicted (R2= 0.69, P ECGs, functional cardiac age can be estimated by multiple linear regression analysis of mostly advanced ECG results. Because some parameters in the regression formula, such as QTcorr, high frequency QRS amplitude and P-wave width also change with disease in the same direction as with increased age, increased functional age of the heart may reflect subtle age-related pathologies in cardiac electrical function that are usually hidden on conventional ECG.

  6. 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.

  7. 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

  8. Quantification of motion artifact in ECG electrode design.

    Science.gov (United States)

    Kearney, Kenneth; Thomas, Chris; McAdams, Eric

    2007-01-01

    We have developed a more accurate and reproducible method of quantifying motion artifact in ECG (electrocardiogram) electrodes to assist in electrode assessment and design. It uses an algorithm developed by Sensor Technology & Devices Ltd. to reliably overcome the variation in results due to differing skin types and other causes of spurious readings such as reproducibility of movements used. The method combines a clear, concise experimental protocol with a software package and DSP algorithm to produce a transferable result for one pair of electrodes that can be used for comparison.

  9. The human ECG nonlinear deterministic versus stochastic aspects

    CERN Document Server

    Kantz, H; Kantz, Holger; Schreiber, Thomas

    1998-01-01

    We discuss aspects of randomness and of determinism in electrocardiographic signals. In particular, we take a critical look at attempts to apply methods of nonlinear time series analysis derived from the theory of deterministic dynamical systems. We will argue that deterministic chaos is not a likely explanation for the short time variablity of the inter-beat interval times, except for certain pathologies. Conversely, densely sampled full ECG recordings possess properties typical of deterministic signals. In the latter case, methods of deterministic nonlinear time series analysis can yield new insights.

  10. 瘤段截骨加热70℃蒸馏水中15 min:灭活回植治疗腓骨近端骨肿瘤%Replantation of inactivated tumor segment boiled in 70℃ distilled water for 15 minutes in the treatment of proximal fibular tumors

    Institute of Scientific and Technical Information of China (English)

    包毅敏; 张国梁; 杜佩晋; 王跃文

    2014-01-01

    BACKGROUND:Apart from a complete resection of tumor tissues, the therapeutic goal for bone tumors is to maximize the repair and restoration of tissue defects and damaged functions. Autologous inactivated bone graft is of practical value for transplantation and reconstruction. OBJECTIVE:To investigate the effect of improved Malawer method combined with replantation of inactivated tumor segment in the treatment of proximal fibular tumors. METHODS: Since 2007, five patients with proximal fibular tumors (six sides) were admitted in the Affiliated Hospital of Inner Mongolia Medical University. These five patients were subjected to distal femoral amputation, intralesional curettage and bone grafting, upper fibular osteotomy + tumor segment heating (boiling in 70℃ distiled water for 15 minutes) + inactivated bone replantation. Therapeutic effects were folowed. RESULTS AND CONCLUSION: One case of amputation had no recurrence and systemic metastasis during 4 years of folow-up; one case of intralesional curettage and bone grafting relapsed 1 year after operation; three cases of upper fibular osteotomy + tumor segment heating + inactivated bone replantation folowed for 5 months recovered walking function and exhibited good healing of the outer structure of the knee, showing non-healing of inactivated tumor segment, non-remarkable calus formation, no local tumor recurrence, no loosening of internal fixation, and inactivated bone without fracture and absorption. These results confirmed that the tumor curettage and amputation both have obvious limitations; based on Malawer method, the replantation of inactive tumor segment can better ensure the structure integrity of the lower leg and in suit reconstruct the lateral biceps femoris tendon and the lateral colateral ligament, but geneticaly the revascularization and healing of inactivated bones wil be difficult and slow with temperature increases, and therefore the period of postoperative brace protection should be relatively

  11. Wearable ECG Based on Impulse-Radio-Type Human Body Communication.

    Science.gov (United States)

    Wang, Jianqing; Fujiwara, Takuya; Kato, Taku; Anzai, Daisuke

    2016-09-01

    Human body communication (HBC) provides a promising physical layer for wireless body area networks (BANs) in healthcare and medical applications, because of its low propagation loss and high security characteristics. In this study, we have developed a wearable electrocardiogram (ECG) which employs impulse radio (IR)-type HBC technology for transmitting vital signals on the human body in a wearable BAN scenario. The HBC-based wearable ECG has two excellent features. First, the wideband performance of the IR scheme contributed to very low radiation power so that the transceiver is easy to satisfy the extremely weak radio laws, which does not need a license. This feature can provide big convenience in the use and spread of the wearable ECG. Second, the realization of common use of sensing and transmitting electrodes based on time sharing and capacitive coupling largely simplified the HBC-based ECG structure and contributed to its miniaturization. To verify the validity of the HBC-based ECG, we evaluated its communication performance and ECG acquisition performance. The measured bit error rate, smaller than 10 (-3) at 1.25 Mb/s, showed a good physical layer communication performance, and the acquired ECG waveform and various heart-rate variability parameters in time and frequency domains exhibited good agreement with a commercially available radio-frequency ECG and a Holter ECG. These results sufficiently showed the validity and feasibility of the HBC-based ECG for healthcare applications. This should be the first time to have realized a real-time ECG transmission by using the HBC technology.

  12. High Resolution of the ECG Signal by Polynomial Approximation

    Directory of Open Access Journals (Sweden)

    G. Rozinaj

    2006-04-01

    Full Text Available Averaging techniques as temporal averaging and space averaging have been successfully used in many applications for attenuating interference [6], [7], [8], [9], [10]. In this paper we introduce interference removing of the ECG signal by polynomial approximation, with smoothing discrete dependencies, to make up for averaging methods. The method is suitable for low-level signals of the electrical activity of the heart often less than 10 m V. Most low-level signals arising from PR, ST and TP segments which can be detected eventually and their physiologic meaning can be appreciated. Of special importance for the diagnostic of the electrical activity of the heart is the activity bundle of His between P and R waveforms. We have established an artificial sine wave to ECG signal between P and R wave. The aim focus is to verify the smoothing method by polynomial approximation if the SNR (signal-to-noise ratio is negative (i.e. a signal is lower than noise.

  13. Retrospectively ECG-gated multi-detector row CT of the chest: does ECG-gating improve three-dimensional visualization of the bronchial tree?

    Energy Technology Data Exchange (ETDEWEB)

    Schertler, T.; Wildermuth, S.; Willmann, J.K.; Crook, D.W.; Marincek, B.; Boehm, T. [Dept. Medical Radiology, Inst. of Diagnostic Radiology, Univ. Hospital Zurich (Switzerland)

    2004-04-01

    Purpose: To determine the impact of retrospectively ECG-gated multi-detector row CT (MDCT) on three-dimensional (3D) visualization of the bronchial tree and virtual bronchoscopy (VB) as compared to non-ECG-gated data acquisition. Materials and Methods: Contrast-enhanced retrospectively ECG-gated and non-ECG-gated MDCT of the chest was performed in 25 consecutive patients referred for assessment of coronary artery bypass grafts and pathology of the ascending aorta. ECG-gated MDCT data were reconstructed in diastole using an absolute reverse delay of -400 msec in all patients. In 10 patients additional reconstructions at -200 msec, -300 msec, and -500 msec prior to the R-wave were performed. Shaded surface display (SSD) and virtual bronchoscopy (VB) for visualization of the bronchial segments was performed with ECG-gated and non-ECG-gated MDCT data. The visualization of the bronchial tree underwent blinded scoring. Effective radiation dose and signal-to-noise ratio (SNR) for both techniques were compared. Results: There was no significant difference in visualizing single bronchial segments using ECG-gated compared to non-ECG-gated MDCT data. However, the total sum of scores for all bronchial segments visualized with non-ECG-gated MDCT was significantly higher compared to ECG-gated MDCT (P<0.05). The summary scores for visualization of bronchial segments for different diastolic reconstructions did not differ significantly. The effective radiation dose and the SNR were significantly higher with the ECG-gated acquisition technique (P<0.05). Conclusion: The bronchial tree is significantly better visualized when using non-ECG-gated MDCT compared to ECG-gated MDCT. Additionally, non-ECG-gated techniques require less radiation exposure. Thus, the current retrospective ECG-gating technique does not provide any additional benefit for 3D visualization of the bronchial tree and VB. (orig.) [German] Ziel: Untersuchung des Einflusses der retrospektiven EKG-Synchronisierung auf

  14. Detectability of motions in AAA with ECG-gated CTA: A quantitative study

    NARCIS (Netherlands)

    Klein, Almar; Oostveen, Luuk J.; Greuter, Marcel J.W.; Hoogeveen, Yvonne; Schultze Kool, Leo J.; Slump, Cornelis H.; Renema, W. Klaas Jan

    2009-01-01

    Purpose: ECG-gated CT enables the visualization of motions caused by the beating of the heart. Although ECG gating is frequently used in cardiac CT imaging, this technique is also very promising for evaluating vessel wall motion of the aortic artery and the motions of (stent grafts inside) abdominal

  15. Detectability of motions in AAA with ECG-gated CTA: a quantitative study.

    NARCIS (Netherlands)

    Klein, A.; Oostveen, L.J.; Greuter, M.J.; Hoogeveen, Y.L.; Kool, L.J.; Slump, C.H.; Renema, W.K.J.

    2009-01-01

    PURPOSE: ECG-gated CT enables the visualization of motions caused by the beating of the heart. Although ECG gating is frequently used in cardiac CT imaging, this technique is also very promising for evaluating vessel wall motion of the aortic artery and the motions of (stent grafts inside) abdominal

  16. Detectability of motions in AAA with ECG-gated CTA : A quantitative study

    NARCIS (Netherlands)

    Klein, Almar; Oostveen, Luuk J.; Greuter, Marcel J. W.; Hoogeveen, Yvonne; Kool, Leo J. Schultze; Slump, Cornelis H.; Renema, W. Klaas Jan

    2009-01-01

    Purpose: ECG-gated CT enables the visualization of motions caused by the beating of the heart. Although ECG gating is frequently used in cardiac CT imaging, this technique is also very promising for evaluating vessel wall motion of the aortic artery and the motions of (stent grafts inside) abdominal

  17. A novel approach for an ECG electrode integrated into a transcutaneous sensor.

    Science.gov (United States)

    Hölscher, U

    1987-01-01

    The integration of an ECG-electrode into a common transcutaneous sensor allows simple handling and leads to a reduction of the physiological stress of pre-term infants. Furthermore it may allow future replacement of an invasive method to measure the ECG under labour by a non-invasive one.

  18. Suppression of baseline wander in the ECG using a bilinearly transformed, null-phase filter.

    Science.gov (United States)

    Pottala, E W; Bailey, J J; Horton, M R; Gradwohl, J R

    1989-01-01

    The purpose of this study was to design and test a bilinearly transformed, null-phase (BLT/NP) filter for removing baseline wander and to compare it with the cubic spline for performance. For this purpose, the ECG data were filtered to remove high-frequency noise and low-frequency baseline wander to form a set of "clean" ECGs. Artificial low-frequency noise mimicking typical baseline wander was constructed from sine and cosine waves at 0.20 and 0.45 Hz and with amplitudes of 400 and 300 microV, respectively, and added to the "clean" ECGs to form the "test" ECGs. The BLT/NP filter and the cubic spline method each were applied to a "test" ECG to form a "restored" ECG. The measure of performance was the root mean square difference (RMSD) between the "restored" ECG and the initial "clean" ECG. RMSD values showed that on the average the BLT/NP filter performed as well as the cubic spline method and has the advantage that accurate determination of the QRS onset is not required.

  19. Interoperability in digital electrocardiography: harmonization of ISO/IEEE x73-PHD and SCP-ECG.

    Science.gov (United States)

    Trigo, Jesús D; Chiarugi, Franco; Alesanco, Alvaro; Martínez-Espronceda, Miguel; Serrano, Luis; Chronaki, Catherine E; Escayola, Javier; Martínez, Ignacio; García, José

    2010-11-01

    The ISO/IEEE 11073 (x73) family of standards is a reference frame for medical device interoperability. A draft for an ECG device specialization (ISO/IEEE 11073-10406-d02) has already been presented to the Personal Health Device (PHD) Working Group, and the Standard Communications Protocol for Computer-Assisted ElectroCardioGraphy (SCP-ECG) Standard for short-term diagnostic ECGs (EN1064:2005+A1:2007) has recently been approved as part of the x73 family (ISO 11073-91064:2009). These factors suggest the coordinated use of these two standards in foreseeable telecardiology environments, and hence the need to harmonize them. Such harmonization is the subject of this paper. Thus, a mapping of the mandatory attributes defined in the second draft of the ISO/IEEE 11073-10406-d02 and the minimum SCP-ECG fields is presented, and various other capabilities of the SCP-ECG Standard (such as the messaging part) are also analyzed from an x73-PHD point of view. As a result, this paper addresses and analyzes the implications of some inconsistencies in the coordinated use of these two standards. Finally, a proof-of-concept implementation of the draft x73-PHD ECG device specialization is presented, along with the conversion from x73-PHD to SCP-ECG. This paper, therefore, provides recommendations for future implementations of telecardiology systems that are compliant with both x73-PHD and SCP-ECG.

  20. An automated ECG system in a large hospital: coding, storage and retrieval of tracings

    NARCIS (Netherlands)

    Meijler, F.L.; Robles de Medina, E.O.; Helder, J.C.

    1975-01-01

    This paper describes an automated ECG-system as it is used in the 1000-bed University Hospital Utrecht, The Netherlands. The system involves a "hybride" approach, combining computer analysis of the ECG by means of the Pipberger program with the reading by a cardiologist via a specially developed cod

  1. Effects of electrocardiography contamination and comparison of ECG removal methods on upper trapezius electromyography recordings.

    Science.gov (United States)

    Marker, Ryan J; Maluf, Katrina S

    2014-12-01

    Electromyography (EMG) recordings from the trapezius are often contaminated by the electrocardiography (ECG) signal, making it difficult to distinguish low-level muscle activity from muscular rest. This study investigates the influence of ECG contamination on EMG amplitude and frequency estimations in the upper trapezius during muscular rest and low-level contractions. A new method of ECG contamination removal, filtered template subtraction (FTS), is described and compared to 30 Hz high-pass filter (HPF) and averaged template subtraction (ATS) methods. FTS creates a unique template of each ECG artifact using a low-pass filtered copy of the contaminated signal, which is subtracted from contaminated periods in the original signal. ECG contamination results in an over-estimation of EMG amplitude during rest in the upper trapezius, with negligible effects on amplitude and frequency estimations during low-intensity isometric contractions. FTS and HPF successfully removed ECG contamination from periods of muscular rest, yet introduced errors during muscle contraction. Conversely, ATS failed to fully remove ECG contamination during muscular rest, yet did not introduce errors during muscle contraction. The relative advantages and disadvantages of different ECG contamination removal methods should be considered in the context of the specific motor tasks that require analysis.

  2. Interactive Videoconference Supported Teaching in Undergraduate Nursing: A Case Study for ECG

    Science.gov (United States)

    Celikkan, Ufuk; Senuzun, Fisun; Sari, Dilek; Sahin, Yasar Guneri

    2013-01-01

    This paper describes how interactive videoconference can benefit the Electrocardiography (ECG) skills of undergraduate nursing students. We have implemented a learning system that interactively transfers the visual and practical aspects of ECG from a nursing skills lab into a classroom where the theoretical part of the course is taught. The…

  3. HIN4/397: Designing the Web- and Fax-based Consultancy and Information Service "EcgConsult" for Clinicians Dealing with ECG Diagnostics and Rhythmologic Problems

    Science.gov (United States)

    Elsner, C; Hindricks, G; Kottkamp, H

    1999-01-01

    /patient identification have been developed. Discussion The platform "EcgConsult" provides a network with fast and easy access to a specific target group and thus allows easy information exchange between the Heart Center Leipzig and rhythmologic experts and non-experts. This exchange may generate synergy effects by offering both groups a variety of data and information. Due to the use of web- and fax-based technology, the access to the service is easy and does not require PC-equipment or a scanner. The requests can be answered by the Heart Center consultants from any remote location world-wide. For the future open-ended architecture allows the participation of further consultants from clinics all over the world. The knowledge gathered from this project may help setting up guidelines for the development of other web-based medical competence centers / information services.

  4. Relative Amplitude based Features of characteristic ECG-Peaks for Identification of Coronary Artery Disease

    Science.gov (United States)

    Gohel, Bakul; Tiwary, U. S.; Lahiri, T.

    Coronary artery disease or Myocardial Infarction is the leading cause of death and disability in the world. ECG is widely used as a cheap diagnostic tool for diagnosis of coronary artery disease but has low sensitivity with the present criteria based on ST-segment, T wave and Q wave changes. So to increase the sensitivity of the ECG we have introduced relative amplitude based new features of characteristic ‘R’ and ‘S’ ECG-peaks between two leads. Relative amplitude based features shows remarkable capability in discriminating Myocardial Infarction and Healthy pattern using backpropogation neural network classifier yield results with 81.82% sensitivity and 81.82% specificity. Also relative amplitude might be an efficient method in minimizing the effect of body composition on ECG amplitude based features without use of any information from other than ECG

  5. 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.

  6. Application of the Wireless Digital Transmission Technology in Remote ECG Monitoring System

    Institute of Scientific and Technical Information of China (English)

    Xu,Lixin; Li,Qingliang; Chen,Zhen; Qi,Xinbo; Zhang,Xincheng

    2005-01-01

    Heart disease is one of the main diseases menace human' s health. The limited monitoring ability and limited serving ability are shortcomings of the existing remote ECG (electrocardiograph) monitoring system. It is practical to bring ECG monitoring from hospital to home. A new method is introduced that the application of wireless digital transmission technology in remote ECG monitoring system. In the system, the portable ECG monitoring device to collect and transmit patient""s electrocardiogram signals and the device to transmit and receive ECG signals are designed by using the PTR2000. The method solves the remote collection and transmission of patient's electrocardiogram signals, and creates the condition of the transmitting of patient"" s electrocardiogram signals through the Broadband network.

  7. Application of the Wireless Digital Transmission Technology in Remote ECG Monitoring System

    Institute of Scientific and Technical Information of China (English)

    Xu,Lixin; Li,Qingliang; Chen,Zhen; Qi,Xinbo; Zhang,Xincheng

    2005-01-01

    Heart disease is one of the main diseases menace human's health. The limited monitoring ability and limited serving ability are shortcomings of the existing remote ECG (electrocardiograph) monitoring system. It is practical to bring ECG monitoring from hospital to home. A new method is introduced that the application of wireless digital transmission technology in remote ECG monitoring system. In the system, the portable ECG monitoring device to collect and transmit patient's electrocardiogram signals and the device to transmit and receive ECG signals are designed by using the PTR2000. The method solves the remote collection and transmission of patient s electrocardiogram signals, and creates the condition of the transmitting of patient's electrocardiogram signals through the Broadband network.

  8. 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...

  9. "ECG variability contour" method reveals amplitude changes in both ischemic patients and normal subjects during Dipyridamole stress: a preliminary report.

    Science.gov (United States)

    Dori, Guy; Gershinsky, Michal; Ben-Haim, Simona; Lewis, Basil S; Bitterman, Haim

    2011-11-01

    To detect and quantify consistent ECG amplitude changes, the "ECG variability contour" (EVC) method was proposed. Using this method we investigated amplitude changes in subjects undergoing myocardial perfusion imaging (MPI) with Dipyridamole (Dp). Fifty-three patients having reversible perfusion defects and 19 normal subjects (NS) who were free of: perfusion defects on their MPI, standard ST-T changes during Dp stress, and a negative clinical follow up. Mean ∏¹() was similar for the NS and patient group (6.2 ± 6.1 vs. 6.3 ± 6.2, P = 0.95). was 4.6 ± 3.0 in patients not having ST-T changes during Dp stress (n = 42), whereas in patients having ST-T changes (n = 11) it was 13.1 ± 10.2 (P was smaller than , which in turn was smaller than . The values of , , and for the NS, patients without and with ST-T changes were: 26.8 ± 28.6, 42.6 ± 41.8, 44.9 ± 36.5; 19.6 ± 20.8, 26.4 ± 31.4, 38.7 ± 27.3; 51.0 ± 30.0, 71.0 ± 36.8, 75.1 ± 20.9, respectively (P EVC method. The EVC method did not distinguish between NS and patients in this clinical setting.

  10. Performance of short ECG recordings twice daily to detect paroxysmal atrial fibrillation in stroke and transient ischemic attack patients

    DEFF Research Database (Denmark)

    Poulsen, Mai B; Binici, Zeynep; Dominguez Vall-Lamora, Maria Helena

    2016-01-01

    AIMS: Prolonged cardiac monitoring after stroke is recommended though there is no consensus on optimal methods. Short-term ECG recordings with a "thumb-ECG" device have shown promising preliminary results regarding effectiveness and cost benefit. We aimed to examine the performance of thumb-ECG a...

  11. Ambulatory recorded ST segment depression on ECG is associated with lower cognitive function in healthy elderly men

    Directory of Open Access Journals (Sweden)

    Sölve Elmståhl

    2009-08-01

    Full Text Available Sölve Elmståhl, Linda FuruängDepartment of Health Sciences, Division of Geriatric Medicine, Lund University, Malmö University Hospital, Malmö, SwedenAbstract: ST segment depression (STDE has been found to be associated with cardiovascular disease in the elderly. Studies of the relation of ambulatory STDE to cognitive function in elderly persons aged 80 years or above is lacking.Objective: To study the association between STDE and cognition.Design and participants: A cross-sectional cohort study of 88 81-year-old men from the population study “Men born in 1914” investigated in an outpatient research clinic. Measurements included ambulatory 24-hour electrocardiogram (ECG monitoring and a cognitive test battery of six tests. Proportion of lower cognitive function was calculated for each test in relation to STDE during the day and at night-time.Results: Fifty-eight percent of the men had STDE and a higher proportion with low visuospatial cognitive function was found among those with STDE compared to the others (84% vs 59%; p = 0.014. A significant trend was noted for subjects without STDE compared to STDE night-time less than 60 minutes and night-time more than 60 minutes for spatial and verbal cognitive functions (p = 0.022. No trends were noted for STDE daytime. Maximal STDE during night showed similar association to spatial function (Benton Visual Retention test, r = -0.26; p = 0.028. Even when seven subjects with a history of stroke were excluded, the occurrence of STDE was associated to lower visuospatial cognitive function compared to those without STDE (87% vs 57%; p = 0.004.Conclusion: ST segment depression on ECG is common among elderly men and might be a vascular risk factor for cognitive deterioration.Keywords: aged 80 and over, ST segment depression, ambulatory long-term ECG, cognition, cohort study, risk factors

  12. Microcontroller-based underwater acoustic ECG telemetry system.

    Science.gov (United States)

    Istepanian, R S; Woodward, B

    1997-06-01

    This paper presents a microcontroller-based underwater acoustic telemetry system for digital transmission of the electrocardiogram (ECG). The system is designed for the real time, through-water transmission of data representing any parameter, and it was used initially for transmitting in multiplexed format the heart rate, breathing rate and depth of a diver using self-contained underwater breathing apparatus (SCUBA). Here, it is used to monitor cardiovascular reflexes during diving and swimming. The programmable capability of the system provides an effective solution to the problem of transmitting data in the presence of multipath interference. An important feature of the paper is a comparative performance analysis of two encoding methods, Pulse Code Modulation (PCM) and Pulse Position Modulation (PPM).

  13. [ECG indices in dogs after inhalation of 239Pu].

    Science.gov (United States)

    Karpova, V N

    1985-11-01

    Dogs of both sexes aged 2 to 4 were subjected to inhalation inoculation with polymer 239Pu or submicron 239PuO2 aerosols in amounts close to acute, subacute and chronically effective ones. ECG was recorded in standard, amplified and single leads (V3). All calculations were done by lead II. Signs of the right heart overburdening were noted in the presence of the P-pulmonale complex, deep S1 wave or cardiac electrical axis of SI-SII-SIII type. Signs of the right heart overburdening were revealed after inhalation of polimer 239Pu (70%). The absence of similar changes in damage caused by 239Pu could be attributed to its fast resorption from the lungs resulting in more moderate lesion of the respiratory organs.

  14. [Prediction of cardiac function deviations (ECG data) in the course of permanent cosmonaut's monitoring starting from selection till return to earth after short-duration space flight].

    Science.gov (United States)

    Kotovskaia, A R; Koloteva, M I; Luk'ianiuk, V Iu; Stepanova, G P; Filatova, L M; Buĭlov, S P; Zhernavkov, A F; Kondratiuk, L L

    2007-01-01

    Analyzed were deviations in cardiac function in 29 cosmonauts with previous aviation and other occupations ranging of 29 to 61 y.o. who made 8- to 30-day space flights (totai number of flights = 34) between 1982 and 2006. The deviations were identified in ECG records collected during clinical selection, clinical physiological examination (CPE) before flight, insertion and deorbit in transport vehicles, and post-flight CPE. Based on the analysis, the cosmonauts were distributed into three groups. The first group (55.2% of the cosmonauts) did not exhibit noticeable shifts and unfavorable trends in ECG at any time of the period of observation. The second group (34.5%) showed some deviations during selection and pre-flight CPE that became more apparent in the period of deorbit and were still present in post-flight ECG records. The third group (10.3%) displayed health-threatening deviations in cardiac function during deorbit. These findings give start to important investigations with the purpose to define permissible medical risks and ensuing establishment and perfection of medical criteria for candidates to cosmonauts with certain health problems.

  15. A importância de um EGC normal em síndromes coronarianas agudas sem supradesnivelamento do segmento ST La importancia de un ECG normal en síndromes coronarios agudos sin supradesnivel del segmento ST The importance of a normal ECG in non-ST elevation acute coronary syndromes

    Directory of Open Access Journals (Sweden)

    Rogério Teixeira

    2010-01-01

    . METHODS: Patients were divided in 2 groups: A (n=538 - Abnormal ECG and B (n=264 - Normal ECG. Normal ECG was synonymous of sinus rhythm and no acute ischemic changes. A one-year clinical follow up was performed targeting all causes of mortality and the MACE rate. RESULTS: Group A patients were older (68.7±11.7 vs. 63.4±12.7Y, p<0.001, had higher Killip classes and peak myocardial necrosis biomarkers. Furthermore, they had lower left ventricular ejection fraction (LVEF (52.01±10.55 vs. 55.34± 9.51%, p<0.001, glomerular filtration rate, initial hemoglobin, and total cholesterol levels. Group B patients were more frequently submitted to invasive strategy (63.6 vs. 46.5%, p<0.001 and treated with aspirin, clopidogrel, beta blockers and statins. They also more often presented normal coronary anatomy (26.2 vs. 18.0%, p=0.45. There was a trend to higher in-hospital mortality in group A (4.6 vs. 1.9%, p=0.054. Kaplan-Meyer analysis showed that at one month and one year (95.1 vs. 89.5%, p=0.012 survival was higher in group B and the result remained significant on a Cox regression model (normal ECG HR 0.45 (0.21 - 0.97. There were no differences regarding the MACE rate. CONCLUSION: In our non-ST elevation ACS population, a normal ECG was an early marker for good prognosis.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  17. An IoT-cloud Based Wearable ECG Monitoring System for Smart Healthcare.

    Science.gov (United States)

    Yang, Zhe; Zhou, Qihao; Lei, Lei; Zheng, Kan; Xiang, Wei

    2016-12-01

    Public healthcare has been paid an increasing attention given the exponential growth human population and medical expenses. It is well known that an effective health monitoring system can detect abnormalities of health conditions in time and make diagnoses according to the gleaned data. As a vital approach to diagnose heart diseases, ECG monitoring is widely studied and applied. However, nearly all existing portable ECG monitoring systems cannot work without a mobile application, which is responsible for data collection and display. In this paper, we propose a new method for ECG monitoring based on Internet-of-Things (IoT) techniques. ECG data are gathered using a wearable monitoring node and are transmitted directly to the IoT cloud using Wi-Fi. Both the HTTP and MQTT protocols are employed in the IoT cloud in order to provide visual and timely ECG data to users. Nearly all smart terminals with a web browser can acquire ECG data conveniently, which has greatly alleviated the cross-platform issue. Experiments are carried out on healthy volunteers in order to verify the reliability of the entire system. Experimental results reveal that the proposed system is reliable in collecting and displaying real-time ECG data, which can aid in the primary diagnosis of certain heart diseases.

  18. Assurance of energy efficiency and data security for ECG transmission in BASNs.

    Science.gov (United States)

    Ma, Tao; Shrestha, Pradhumna Lal; Hempel, Michael; Peng, Dongming; Sharif, Hamid; Chen, Hsiao-Hwa

    2012-04-01

    With the technological advancement in body area sensor networks (BASNs), low cost high quality electrocardiographic (ECG) diagnosis systems have become important equipment for healthcare service providers. However, energy consumption and data security with ECG systems in BASNs are still two major challenges to tackle. In this study, we investigate the properties of compressed ECG data for energy saving as an effort to devise a selective encryption mechanism and a two-rate unequal error protection (UEP) scheme. The proposed selective encryption mechanism provides a simple and yet effective security solution for an ECG sensor-based communication platform, where only one percent of data is encrypted without compromising ECG data security. This part of the encrypted data is essential to ECG data quality due to its unequally important contribution to distortion reduction. The two-rate UEP scheme achieves a significant additional energy saving due to its unequal investment of communication energy to the outcomes of the selective encryption, and thus, it maintains a high ECG data transmission quality. Our results show the improvements in communication energy saving of about 40%, and demonstrate a higher transmission quality and security measured in terms of wavelet-based weighted percent root-mean-squared difference.

  19. Low-power analog integrated circuits for wireless ECG acquisition systems.

    Science.gov (United States)

    Tsai, Tsung-Heng; Hong, Jia-Hua; Wang, Liang-Hung; Lee, Shuenn-Yuh

    2012-09-01

    This paper presents low-power analog ICs for wireless ECG acquisition systems. Considering the power-efficient communication in the body sensor network, the required low-power analog ICs are developed for a healthcare system through miniaturization and system integration. To acquire the ECG signal, a low-power analog front-end system, including an ECG signal acquisition board, an on-chip low-pass filter, and an on-chip successive-approximation analog-to-digital converter for portable ECG detection devices is presented. A quadrature CMOS voltage-controlled oscillator and a 2.4 GHz direct-conversion transmitter with a power amplifier and upconversion mixer are also developed to transmit the ECG signal through wireless communication. In the receiver, a 2.4 GHz fully integrated CMOS RF front end with a low-noise amplifier, differential power splitter, and quadrature mixer based on current-reused folded architecture is proposed. The circuits have been implemented to meet the specifications of the IEEE 802.15.4 2.4 GHz standard. The low-power ICs of the wireless ECG acquisition systems have been fabricated using a 0.18 μm Taiwan Semiconductor Manufacturing Company (TSMC) CMOS standard process. The measured results on the human body reveal that ECG signals can be acquired effectively by the proposed low-power analog front-end ICs.

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

    Science.gov (United States)

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

    2013-05-01

    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.

  1. Classification of a Driver's cognitive workload levels using artificial neural network on ECG signals.

    Science.gov (United States)

    Tjolleng, Amir; Jung, Kihyo; Hong, Wongi; Lee, Wonsup; Lee, Baekhee; You, Heecheon; Son, Joonwoo; Park, Seikwon

    2017-03-01

    An artificial neural network (ANN) model was developed in the present study to classify the level of a driver's cognitive workload based on electrocardiography (ECG). ECG signals were measured on 15 male participants while they performed a simulated driving task as a primary task with/without an N-back task as a secondary task. Three time-domain ECG measures (mean inter-beat interval (IBI), standard deviation of IBIs, and root mean squared difference of adjacent IBIs) and three frequencydomain ECG measures (power in low frequency, power in high frequency, and ratio of power in low and high frequencies) were calculated. To compensate for individual differences in heart response during the driving tasks, a three-step data processing procedure was performed to ECG signals of each participant: (1) selection of two most sensitive ECG measures, (2) definition of three (low, medium, and high) cognitive workload levels, and (3) normalization of the selected ECG measures. An ANN model was constructed using a feed-forward network and scaled conjugate gradient as a back-propagation learning rule. The accuracy of the ANN classification model was found satisfactory for learning data (95%) and testing data (82%).

  2. Deployment of an Advanced Electrocardiographic Analysis (A-ECG) to Detect Cardiovascular Risk in Career Firefighters

    Science.gov (United States)

    Dolezal, B. A.; Storer, T. W.; Abrazado, M.; Watne, R.; Schlegel, T. T.; Batalin, M.; Kaiser, W.; Smith, D. L.; Cooper, C. B.

    2011-01-01

    INTRODUCTION: Sudden cardiac death is the leading cause of line of duty death among firefighters, accounting for approximately 45% of fatalities annually. Firefighters perform strenuous muscular work while wearing heavy, encapsulating personal protective equipment in high ambient temperatures, under chaotic and emotionally stressful conditions. These factors can precipitate sudden cardiac events like myocardial infarction, serious dysrhythmias, or cerebrovascular accidents in firefighters with underlying cardiovascular disease. PURPOSE: The purpose of this study was to deploy and then evaluate the contribution of resting advanced ECG (A-ECG) in addition to other screening tools (family history, lipid profiles, and cardiopulmonary exercise tests, XT) in assessment of an individual fs cardiac risk profile. METHODS: Forty-four career firefighters were recruited to perform comprehensive baseline assessments including tests of aerobic performance, fasting lipids and glucose. Five-min resting 12-lead A-ECGs were obtained in a subset of firefighters (n=21) and transmitted over a secure networked system to a NASA physician collaborator. Using myocardial perfusion and other imaging as the gold standard, A-ECG scoring has been proven useful in accurately identifying a number of cardiac pathologies including coronary artery disease (CAD), left ventricular hypertrophy, hypertrophic cardiomyopathy, and non-ischemic and ischemic cardiomyopathy. RESULTS: Subjects f mean (SD) age was 43 (8) years, weight 91 (13) kg, and BMI 28 (3) kg/m2. Fifty-one percent of subjects had .3 cardiovascular risk factors. One subject had ST depression on XT ECG, at least one positive A-ECG score for CAD, and documented CAD based on cardiology referral. While all other subjects, including those with fewer risk factors, higher aerobic fitness, and normal exercise ECGs, were classified as healthy by A-ECG, there was no trend for association between risk factors and any of 20 A-ECG parameters in the

  3. Detection of Cardiac Abnormalities from Multilead ECG using Multiscale Phase Alternation Features.

    Science.gov (United States)

    Tripathy, R K; Dandapat, S

    2016-06-01

    The cardiac activities such as the depolarization and the relaxation of atria and ventricles are observed in electrocardiogram (ECG). The changes in the morphological features of ECG are the symptoms of particular heart pathology. It is a cumbersome task for medical experts to visually identify any subtle changes in the morphological features during 24 hours of ECG recording. Therefore, the automated analysis of ECG signal is a need for accurate detection of cardiac abnormalities. In this paper, a novel method for automated detection of cardiac abnormalities from multilead ECG is proposed. The method uses multiscale phase alternation (PA) features of multilead ECG and two classifiers, k-nearest neighbor (KNN) and fuzzy KNN for classification of bundle branch block (BBB), myocardial infarction (MI), heart muscle defect (HMD) and healthy control (HC). The dual tree complex wavelet transform (DTCWT) is used to decompose the ECG signal of each lead into complex wavelet coefficients at different scales. The phase of the complex wavelet coefficients is computed and the PA values at each wavelet scale are used as features for detection and classification of cardiac abnormalities. A publicly available multilead ECG database (PTB database) is used for testing of the proposed method. The experimental results show that, the proposed multiscale PA features and the fuzzy KNN classifier have better performance for detection of cardiac abnormalities with sensitivity values of 78.12 %, 80.90 % and 94.31 % for BBB, HMD and MI classes. The sensitivity value of proposed method for MI class is compared with the state-of-art techniques from multilead ECG.

  4. Clinically relevant QTc prolongation due to overridden drug-drug interaction alerts: A retrospective cohort study

    NARCIS (Netherlands)

    I.H. van der Sijs (Heleen); R. Kowlesar (Ravi); A.P.J. Klootwijk (Peter); S.P. Nelwan (Stefan); A.G. Vulto (Arnold); T. van Gelder (Teun)

    2009-01-01

    textabstractAIMS: To investigate whether, in patients in whom drug-drug interaction (DDI) alerts on QTc prolongation were overridden, the physician had requested an electrocardiogram (ECG), and if these ECGs showed clinically relevant QTc prolongation. METHODS: For all patients with overridden DDI a

  5. Single Channel Fetal ECG Detection Using LMS and RLS Adaptive Filters

    Institute of Scientific and Technical Information of China (English)

    Alaa Aldoori; Ali Buniya; ZHENG Zheng

    2015-01-01

    ECG is an important tool for the primary diagnosis of heart diseases, which shows the electrophysiology of the heart. In our method, a single maternal abdominal ECG signal is taken as an input signal and the maternal P-QRS-T complexes of original signal is averaged and repeated and taken as a reference signal. LMS and RLS adaptive filters algorithms are applied. The results showed that the fetal ECGs have been successfully detected. The accuracy of Daisy database was up to 84%of LMS and 88%of RLS while PhysioNet was up to 98%and 96%for LMS and RLS respectively.

  6. Evaluation of novel ECG signal processing on quantification of transient ischemia and baseline wander suppression.

    Science.gov (United States)

    Kostic, Marko N; Fakhar, Sina; Foxall, Tom; Drakulic, Budimir S; Krucoff, Mitchell W

    2007-01-01

    The performance assessment of a novel ECG signal processing technology in Fidelity 100 (test) and four modern ECG systems (controls) was conducted. A quantitative evaluation for one control and a test system was done by simultaneous recordings on 54 patients undergoing percutaneous coronary intervention (PCI) and on a biological reference signal from an ECG simulator. A qualitative performance of baseline wander suppression was done on all five systems. The results showed that the Fidelity 100 system provided excellent detection and quantification of transient ischemia and baseline wander suppression.

  7. Real-time ECG emulation: a multiple dipole model for electrocardiography simulation.

    Science.gov (United States)

    Abkai, Ciamak; Hesser, Jürgen

    2009-01-01

    A new model for describing electrocardiography (ECG) is presented, which is based on multiple dipoles compared to standard single dipole approaches in vector electrocardiography. The multiple dipole parameters are derived from real data (e.g. four dipoles from 12-channel ECG) by solving the backward problem of ECG numerically. Results are transformed to a waveform description based on Gaussian mixture for every dimension of each dipole. These compact parameterized descriptors are used for a very realistic real-time simulation applying the forward solution of the proposed model.

  8. Principal component cluster analysis of ECG time series based on Lyapunov exponent spectrum

    Institute of Scientific and Technical Information of China (English)

    WANG Nai; RUAN Jiong

    2004-01-01

    In this paper we propose an approach of principal component cluster analysis based on Lyapunov exponent spectrum (LES) to analyze the ECG time series. Analysis results of 22 sample-files of ECG from the MIT-BIH database confirmed the validity of our approach. Another technique named improved teacher selecting student (TSS) algorithm is presented to analyze unknown samples by means of some known ones, which is of better accuracy. This technique combines the advantages of both statistical and nonlinear dynamical methods and is shown to be significant to the analysis of nonlinear ECG time series.

  9. Improving local PCA in pseudo phase space for fetal heart rate estimation from single lead abdominal ECG.

    Science.gov (United States)

    Wei, Zheng; Hongxing, Liu; Jianchun, Cheng

    2011-12-01

    This paper proposes an improved local principal component analysis (LPCA) in pseudo phase space for fetal heart rate estimation from a single lead abdominal ECG signal. The improved LPCA process can extract both the maternal ECG component and the fetal ECG component in an abdominal signal. The instantaneous fetal heart rate can then be estimated from the extracted fetal ECG waveform. Compared with the classical LPCA procedure and another single lead based fetal heart rate estimation method, our improved LPCA method has shown better robustness and efficiency in fetal heart estimation, testing with synthetic ECG signals and a real fetal ECG database from PhysioBank. For the real fetal ECG validating dataset of six long-duration recordings (obtained between the 22(nd) and 40(th) week of gestation), the average accuracy of the improved LPCA method is 84.1%.

  10. Recommendations for the standardization and interpretation of the electrocardiogram: part I: the electrocardiogram and its technology a scientific statement from the American Heart Association Electrocardiography and Arrhythmias Committee, Council on Clinical Cardiology; the American College of Cardiology Foundation; and the Heart Rhythm Society endorsed by the International Society for Computerized Electrocardiology.

    Science.gov (United States)

    Kligfield, Paul; Gettes, Leonard S; Bailey, James J; Childers, Rory; Deal, Barbara J; Hancock, E William; van Herpen, Gerard; Kors, Jan A; Macfarlane, Peter; Mirvis, David M; Pahlm, Olle; Rautaharju, Pentti; Wagner, Galen S; Josephson, Mark; Mason, Jay W; Okin, Peter; Surawicz, Borys; Wellens, Hein

    2007-03-13

    This statement examines the relation of the resting ECG to its technology. Its purpose is to foster understanding of how the modern ECG is derived and displayed and to establish standards that will improve the accuracy and usefulness of the ECG in practice. Derivation of representative waveforms and measurements based on global intervals are described. Special emphasis is placed on digital signal acquisition and computer-based signal processing, which provide automated measurements that lead to computer-generated diagnostic statements. Lead placement, recording methods, and waveform presentation are reviewed. Throughout the statement, recommendations for ECG standards are placed in context of the clinical implications of evolving ECG technology.

  11. Recommendations for the standardization and interpretation of the electrocardiogram: part I: The electrocardiogram and its technology: a scientific statement from the American Heart Association Electrocardiography and Arrhythmias Committee, Council on Clinical Cardiology; the American College of Cardiology Foundation; and the Heart Rhythm Society: endorsed by the International Society for Computerized Electrocardiology.

    Science.gov (United States)

    Kligfield, Paul; Gettes, Leonard S; Bailey, James J; Childers, Rory; Deal, Barbara J; Hancock, E William; van Herpen, Gerard; Kors, Jan A; Macfarlane, Peter; Mirvis, David M; Pahlm, Olle; Rautaharju, Pentti; Wagner, Galen S; Josephson, Mark; Mason, Jay W; Okin, Peter; Surawicz, Borys; Wellens, Hein

    2007-03-13

    This statement examines the relation of the resting ECG to its technology. Its purpose is to foster understanding of how the modern ECG is derived and displayed and to establish standards that will improve the accuracy and usefulness of the ECG in practice. Derivation of representative waveforms and measurements based on global intervals are described. Special emphasis is placed on digital signal acquisition and computer-based signal processing, which provide automated measurements that lead to computer-generated diagnostic statements. Lead placement, recording methods, and waveform presentation are reviewed. Throughout the statement, recommendations for ECG standards are placed in context of the clinical implications of evolving ECG technology.

  12. Unobtrusive monitoring of ECG-derived features during daily smartphone use.

    Science.gov (United States)

    Kwon, Sungjun; Kang, Seungwoo; Lee, Youngki; Yoo, Chungkuk; Park, Kwangsuk

    2014-01-01

    Heart rate variability (HRV) is known to be one of the representative ECG-derived features that are useful for diverse pervasive healthcare applications. The advancement in daily physiological monitoring technology is enabling monitoring of HRV in people's everyday lives. In this study, we evaluate the feasibility of measuring ECG-derived features such as HRV, only using the smartphone-integrated ECG sensors system named Sinabro. We conducted the evaluation with 13 subjects in five predetermined smartphone use cases. The result shows the potential that the smartphone-based sensing system can support daily monitoring of ECG-derived features; The average errors of HRV over all participants ranged from 1.65% to 5.83% (SD: 2.54~10.87) for five use cases. Also, all of individual HRV parameters showed less than 5% of average errors for the three reliable cases.

  13. Compression and Encryption of ECG Signal Using Wavelet and Chaotically Huffman Code in Telemedicine Application.

    Science.gov (United States)

    Raeiatibanadkooki, Mahsa; Quchani, Saeed Rahati; KhalilZade, MohammadMahdi; Bahaadinbeigy, Kambiz

    2016-03-01

    In mobile health care monitoring, compression is an essential tool for solving storage and transmission problems. The important issue is able to recover the original signal from the compressed signal. The main purpose of this paper is compressing the ECG signal with no loss of essential data and also encrypting the signal to keep it confidential from everyone, except for physicians. In this paper, mobile processors are used and there is no need for any computers to serve this purpose. After initial preprocessing such as removal of the baseline noise, Gaussian noise, peak detection and determination of heart rate, the ECG signal is compressed. In compression stage, after 3 steps of wavelet transform (db04), thresholding techniques are used. Then, Huffman coding with chaos for compression and encryption of the ECG signal are used. The compression rates of proposed algorithm is 97.72 %. Then, the ECG signals are sent to a telemedicine center to acquire specialist diagnosis by TCP/IP protocol.

  14. ECG Sensor Verification System with Mean-Interval Algorithm for Handling Sport Issue

    Directory of Open Access Journals (Sweden)

    Kuo-Kun Tseng

    2016-01-01

    Full Text Available With the development of biometric verification, we proposed a new algorithm and personal mobile sensor card system for ECG verification. The proposed new mean-interval approach can identify the user quickly with high accuracy and consumes a small amount of flash memory in the microprocessor. The new framework of the mobile card system makes ECG verification become a feasible application to overcome the issues of a centralized database. For a fair and comprehensive evaluation, the experimental results have been tested on public MIT-BIH ECG databases and our circuit system; they confirm that the proposed scheme is able to provide excellent accuracy and low complexity. Moreover, we also proposed a multiple-state solution to handle the heat rate changes of sports problem. It should be the first to address the issue of sports in ECG verification.

  15. Periodic Noise Suppression from ECG Signal using Novel Adaptive Filtering Techniques

    Directory of Open Access Journals (Sweden)

    Yogesh Sharma

    2012-03-01

    Full Text Available Electrocardiogram signal most commonly known recognized and used biomedical signal for medical examination of heart. The ECG signal is very sensitive in nature, and even if small noise mixed with original signal, the various characteristics of the signal changes, Data corrupted with noise must either filtered or discarded, filtering is important issue for design consideration of real time heart monitoring systems. Various filters used for removing the noise from ECG signals, most commonly used filters are Notch Filters, FIR filters, IIR filters, Wiener filter, Adaptive filters etc. Performance analysis shows that the best result is obtained by using Adaptive filter to remove various noises from ECG signal and get significant SNR andMSE results. In this paper a novel adaptive approach by using LMS algorithm and delay has shown whichcan be used for pre-processing of ECG signal and give appreciable result.

  16. A Human ECG Identification System Based on Ensemble Empirical Mode Decomposition

    Directory of Open Access Journals (Sweden)

    Yi Luo

    2013-05-01

    Full Text Available In this paper, a human electrocardiogram (ECG identification system based on ensemble empirical mode decomposition (EEMD is designed. A robust preprocessing method comprising noise elimination, heartbeat normalization and quality measurement is proposed to eliminate the effects of noise and heart rate variability. The system is independent of the heart rate. The ECG signal is decomposed into a number of intrinsic mode functions (IMFs and Welch spectral analysis is used to extract the significant heartbeat signal features. Principal component analysis is used reduce the dimensionality of the feature space, and the K-nearest neighbors (K-NN method is applied as the classifier tool. The proposed human ECG identification system was tested on standard MIT-BIH ECG databases: the ST change database, the long-term ST database, and the PTB database. The system achieved an identification accuracy of 95% for 90 subjects, demonstrating the effectiveness of the proposed method in terms of accuracy and robustness.

  17. Design of wavelet-based ECG detector for implantable cardiac pacemakers.

    Science.gov (United States)

    Min, Young-Jae; Kim, Hoon-Ki; Kang, Yu-Ri; Kim, Gil-Su; Park, Jongsun; Kim, Soo-Won

    2013-08-01

    A wavelet Electrocardiogram (ECG) detector for low-power implantable cardiac pacemakers is presented in this paper. The proposed wavelet-based ECG detector consists of a wavelet decomposer with wavelet filter banks, a QRS complex detector of hypothesis testing with wavelet-demodulated ECG signals, and a noise detector with zero-crossing points. In order to achieve high detection accuracy with low power consumption, a multi-scaled product algorithm and soft-threshold algorithm are efficiently exploited in our ECG detector implementation. Our algorithmic and architectural level approaches have been implemented and fabricated in a standard 0.35 μm CMOS technology. The testchip including a low-power analog-to-digital converter (ADC) shows a low detection error-rate of 0.196% and low power consumption of 19.02 μW with a 3 V supply voltage.

  18. Heart Beat Detection in Noisy ECG Signals Using Statistical Analysis of the Automatically Detected Annotations

    Directory of Open Access Journals (Sweden)

    Andrius Gudiškis

    2015-07-01

    Full Text Available This paper proposes an algorithm to reduce the noise distortion influence in heartbeat annotation detection in electrocardiogram (ECG signals. Boundary estimation module is based on energy detector. Heartbeat detection is usually performed by QRS detectors that are able to find QRS regions in a ECG signal that are a direct representation of a heartbeat. However, QRS performs as intended only in cases where ECG signals have high signal to noise ratio, when there are more noticeable signal distortion detectors accuracy decreases. Proposed algorithm uses additional data, taken from arterial blood pressure signal which was recorded in parallel to ECG signal, and uses it to support the QRS detection process in distorted signal areas. Proposed algorithm performs as well as classical QRS detectors in cases where signal to noise ratio is high, compared to the heartbeat annotations provided by experts. In signals with considerably lower signal to noise ratio proposed algorithm improved the detection accuracy to up to 6%.

  19. Check your biosignals here: a new dataset for off-the-person ECG biometrics.

    Science.gov (United States)

    da Silva, Hugo Plácido; Lourenço, André; Fred, Ana; Raposo, Nuno; Aires-de-Sousa, Marta

    2014-02-01

    The Check Your Biosignals Here initiative (CYBHi) was developed as a way of creating a dataset and consistently repeatable acquisition framework, to further extend research in electrocardiographic (ECG) biometrics. In particular, our work targets the novel trend towards off-the-person data acquisition, which opens a broad new set of challenges and opportunities both for research and industry. While datasets with ECG signals collected using medical grade equipment at the chest can be easily found, for off-the-person ECG data the solution is generally for each team to collect their own corpus at considerable expense of resources. In this paper we describe the context, experimental considerations, methods, and preliminary findings of two public datasets created by our team, one for short-term and another for long-term assessment, with ECG data collected at the hand palms and fingers.

  20. Performance analysis of adjustable window based FIR filter for noisy ECG Signal Filtering

    Directory of Open Access Journals (Sweden)

    N. Mahawar

    2013-09-01

    Full Text Available Recording of the electrical activity associated to heart functioning is known as Electrocardiogram (ECG. ECG is a quasi-periodical, rhythmically signal synchronized by the function of the heart, which acts as a generator of bioelectric events. ECG signals are low level signals and sensitive to external contaminations. Electrocardiogram signals are often corrupted by noise which may have electrical or electrophysiological origin. The noise signal tends to alter the signal morphology, thereby hindering the correct diagnosis. In order to remove the unwanted noise, a digital filtering technique based on adjustable windows is proposed in this paper. Finite Impulse Response (FIR low pass is designed using windowing method for the ECG signal. The results obtained from different techniques are compared on the basis of popularly used signal error measures like SNR, PRD, PRD1, and MSE.

  1. Quantification of Intracranial Aneurysm Morphodynamics from ECG-gated CT Angiography

    NARCIS (Netherlands)

    Firouzian, A.; Manniesing, R.; Metz, C.T.; Risselada, R.; Klein, S.; Kooten, F. van; Sturkenboom, M.C.; Lugt, A. van der; Niessen, W.J.

    2013-01-01

    Rationale and Objectives: Aneurysm morphodynamics is potentially relevant for assessing aneurysm rupture risk. A method is proposed for automated quantification and visualization of intracranial aneurysm morphodynamics from ECG-gated computed tomography angiography (CTA) data. Materials and Methods:

  2. An ECG Compressed Sensing Method of Low Power Body Area Network

    Directory of Open Access Journals (Sweden)

    Jizhong Liu

    2013-07-01

    Full Text Available Aimed at low power problem in body area network, an ECG compressed sensing method of low power body area network based on the compressed sensing theory was proposed. Random binary matrices were used as the sensing matrix to measure ECG signals on the sensor nodes. After measured value is transmitted to remote monitoring center, ECG signal sparse representation under the discrete cosine transform and block sparse Bayesian learning reconstruction algorithm is used to reconstruct the ECG signals. The simulation results show that the 30% of overall signal can get reconstruction signal which’s SNR is more than 60dB, each numbers in each rank of sensing matrix can be controlled below 5, which reduces the power of sensor node sampling, calculation and transmission. The method has the advantages of low power, high accuracy of signal reconstruction and easy to hardware implementation.  

  3. [Study on mobile phone based wireless ECG monitoring technology system typical demonstration applications].

    Science.gov (United States)

    Yu, Yang; Liu, Jing

    2011-01-01

    Based on the mobile phone platform with wireless real-time ECG monitoring system developed in our lab, this article is dedicated to evaluate its practical value in people test. A series of new conceptual experiments were designed and performed. Particularly, ECG characteristics under different age, gender, health and motion conditions are evaluated. Effects of living habits such as drinking wine, coffee including various psychological conditions such as excitation, anxiety etc. to the ECG response are investigated. The human ECG under different time in a day such as morning, afternoon and late-night was evaluated. These conceptual experiments, which are hard to conduct otherwise using conventional devices, demonstrate the pervasive merits of the new system for fundamental study of heart disease as well as daily healthcare.

  4. Practical Non-contact ECG Electrodes for Prep-free Monitoring Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Cognionics has developed a high-quality, low-noise, dry/non-contact ECG electrode that can obtain signals even through layers of clothing without any skin...

  5. CinC Challenge 2013: comparing three algorithms to extract fetal ECG

    Science.gov (United States)

    Loja, Juan; Velecela, Esteban; Palacio-Baus, Kenneth; Astudillo, Darwin; Medina, Rubén.; Wong, Sara

    2015-12-01

    This paper reports a comparison between three fetal ECG (fECG) detectors developed during the CinC 2013 challenge for fECG detection. Algorithm A1 is based on Independent Component Analysis, A2 is based on fECG detection of RS Slope and A3 is based on Expectation-Weighted Estimation of Fiducial Points. The proposed methodology was validated using the annotated database available for the challenge. Each detector was characterized in terms of its performance by using measures of sensitivity, (Se), positive predictive value (P+) and delay time (td). Additionally, the database was contaminated with white noise for two SNR conditions. Decision fusion was tested considering the most common types of combination of detectors. Results show that the decision fusion of A1 and A2 improves fQRS detection, maintaining high Se and P+ even under low SNR conditions without a significant td increase.

  6. ECG Based Heart Arrhythmia Detection Using Wavelet Coherence and Bat Algorithm

    Science.gov (United States)

    Kora, Padmavathi; Sri Rama Krishna, K.

    2016-12-01

    Atrial fibrillation (AF) is a type of heart abnormality, during the AF electrical discharges in the atrium are rapid, results in abnormal heart beat. The morphology of ECG changes due to the abnormalities in the heart. This paper consists of three major steps for the detection of heart diseases: signal pre-processing, feature extraction and classification. Feature extraction is the key process in detecting the heart abnormality. Most of the ECG detection systems depend on the time domain features for cardiac signal classification. In this paper we proposed a wavelet coherence (WTC) technique for ECG signal analysis. The WTC calculates the similarity between two waveforms in frequency domain. Parameters extracted from WTC function is used as the features of the ECG signal. These features are optimized using Bat algorithm. The Levenberg Marquardt neural network classifier is used to classify the optimized features. The performance of the classifier can be improved with the optimized features.

  7. Feasibility of epicardial adipose tissue quantification in non-ECG-gated low-radiation-dose CT: comparison with prospectively ECG-gated cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Simon-Yarza, Isabel; Viteri-Ramirez, Guillermo; Saiz-Mendiguren, Ramon; Slon-Roblero, Pedro J.; Paramo, Maria [Dept. of Radiology, Clinica Univ. de Navarra, Pamplona (Spain); Bastarrika, Gorka [Dept. of Radiology, Clinica Univ. de Navarra, Pamplona (Spain); Cardiac Imaging Unit, Clinica Univ. de Navarra, Pamplona (Spain)], e-mail: bastarrika@unav.es

    2012-06-15

    Background: Epicardial adipose tissue (EAT) is an important indicator of cardiovascular risk. This parameter is generally assessed on ECG-gated computed tomography (CT) images. Purpose: To evaluate feasibility and reliability of EAT quantification on non-gated thoracic low-radiation-dose CT examinations with respect to prospectively ECG-gated cardiac CT acquisition. Material and Methods: Sixty consecutive asymptomatic smokers (47 men; mean age 64 {+-} 9.8 years) underwent low-dose CT of the chest and prospectively ECG-gated cardiac CT acquisitions (64-slice dual-source CT). The two examinations were reconstructed with the same range, field of view, slice thickness, and convolution algorithm. Two independent observers blindly quantified EAT volume using commercially available software. Data were compared with paired sample Student t-test, concordance correlation coefficients (CCC), and Bland-Altman plots. Results: No statistically significant difference was observed for EAT volume quantification with low-dose-CT (141.7 {+-} 58.3 mL) with respect to ECG-gated CT (142.7 {+-} 57.9 mL). Estimation of CCC showed almost perfect concordance between the two techniques for EAT-volume assessment (CCC, 0.99; mean difference, 0.98 {+-} 5.1 mL). Inter-observer agreement for EAT volume estimation was CCC: 0.96 for low-dose-CT examinations and 0.95 for ECG-gated CT. Conclusion: Non-gated low-dose CT allows quantifying EAT with almost the same concordance and reliability as using dedicated prospectively ECG-gated cardiac CT acquisition protocols.

  8. Motion artifact removal algorithm by ICA for e-bra: a women ECG measurement system

    Science.gov (United States)

    Kwon, Hyeokjun; Oh, Sechang; Varadan, Vijay K.

    2013-04-01

    Wearable ECG(ElectroCardioGram) measurement systems have increasingly been developing for people who suffer from CVD(CardioVascular Disease) and have very active lifestyles. Especially, in the case of female CVD patients, several abnormal CVD symptoms are accompanied with CVDs. Therefore, monitoring women's ECG signal is a significant diagnostic method to prevent from sudden heart attack. The E-bra ECG measurement system from our previous work provides more convenient option for women than Holter monitor system. The e-bra system was developed with a motion artifact removal algorithm by using an adaptive filter with LMS(least mean square) and a wandering noise baseline detection algorithm. In this paper, ICA(independent component analysis) algorithms are suggested to remove motion artifact factor for the e-bra system. Firstly, the ICA algorithms are developed with two kinds of statistical theories: Kurtosis, Endropy and evaluated by performing simulations with a ECG signal created by sgolayfilt function of MATLAB, a noise signal including 0.4Hz, 1.1Hz and 1.9Hz, and a weighed vector W estimated by kurtosis or entropy. A correlation value is shown as the degree of similarity between the created ECG signal and the estimated new ECG signal. In the real time E-Bra system, two pseudo signals are extracted by multiplying with a random weighted vector W, the measured ECG signal from E-bra system, and the noise component signal by noise extraction algorithm from our previous work. The suggested ICA algorithm basing on kurtosis or entropy is used to estimate the new ECG signal Y without noise component.

  9. A wavelet-based ECG delineation algorithm for 32-bit integer online processing

    OpenAIRE

    Chiari Lorenzo; Di Marco Luigi Y

    2011-01-01

    Abstract Background 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 implementati...

  10. Modulations of Heart Rate, ECG, and Cardio-Respiratory Coupling Observed in Polysomnography

    OpenAIRE

    Penzel, Thomas; Kantelhardt, Jan W.; Bartsch, Ronny P.; Riedl, Maik; Kraemer, Jan F.; Wessel, Niels; Garcia, Carmen; Glos, Martin; Fietze, Ingo; Schöbel, Christoph

    2016-01-01

    The cardiac component of cardio-respiratory polysomnography is covered by ECG and heart rate recordings. However, their evaluation is often underrepresented in summarizing reports. As complements to EEG, EOG, and EMG, these signals provide diagnostic information for autonomic nervous activity during sleep. This review presents major methodological developments in sleep research regarding heart rate, ECG, and cardio-respiratory couplings in a chronological (historical) sequence. It presents ph...

  11. Modulations of Heart Rate, ECG, and Cardio-Respiratory Coupling Observed in Polysomnography

    OpenAIRE

    Thomas Penzel; Kantelhardt, Jan W.; Bartsch, Ronny P.; Maik Riedl; Jan Krämer; Niels Wessel; Carmen Garcia; Martin Glos; Ingo Fietze; Christoph Schöbel

    2016-01-01

    The cardiac component of cardio-respiratory polysomnography is covered by ECG and heart rate recordings. However their evaluation is often underrepresented in summarizing reports. As complements to EEG, EOG, and EMG, these signals provide diagnostic information for autonomic nervous activity during sleep. This review presents major methodological developments in sleep research regarding heart rate, ECG and cardio-respiratory couplings in a chronological (historical) sequence. It presents phys...

  12. Removal of Baseline Wander Noise from Electrocardiogram (ECG) using Fifth-order Spline Interpolation

    OpenAIRE

    John A. OJO; Temilade B. ADETOYI; Solomon A. Adeniran

    2016-01-01

    Baseline wandering can mask some important features of the Electrocardiogram (ECG) signal hence it is desirable to remove this noise for proper analysis and display of the ECG signal. This paper presents the implementation and evaluation of spline interpolation and linear phase FIR filtering methods to remove this noise. Spline interpolation method requires the QRS waves to be first detected and fifth-order (quintic) interpolation technique applied to determine the smo...

  13. 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

  14. Low-dose prospective ECG-triggering dual-source CT angiography in infants and children with complex congenital heart disease: first experience

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Zhaoping; Wang, Ximing; Duan, Yanhua; Wu, Lebin; Wu, Dawei; Chao, Baoting; Liu, Cheng; Xu, Zhuodong [Shandong University, Shandong Medical Imaging Research Institute, Jinan, Shandong (China); Li, Hongxin; Liang, Fei [Shandong Provincial Hospital, Department of Cardiovascular Surgery, Jinan, Shandong (China); Xu, Jian; Chen, Jiuhong [Siemens. Ltd. China, CT Research Collaboration, Beijing (China)

    2010-10-15

    To explore the clinical value of low-dose prospective ECG-triggering dual-source CT (DSCT) angiography in infants and children with complex congenital heart disease (CHD) compared with transthoracic echocardiography (TTE). Thirty-five patients (mean age: 16 months, range: 2 months to 6 years; male 15; mean weight: 12 kg) underwent low-dose prospective ECG-triggering DSCT angiography and TTE. Surgeries were performed in 29 patients, and conventional cardiac angiography (CCA) was performed in 8 patients. The accuracy was calculated based on the surgical and/or CCA findings. The overall imaging quality was evaluated on a five-point scale. A total of 146 separate cardiovascular deformities were confirmed. DSCT missed three atrial septal defects and a patent ductus arteriosus. The accuracy of DSCT angiography and TTE was 97.3% (142/146) and 92.5% (135/146), respectively. Overall test parameters for DSCT angiography and TTE were similar (sensitivity, 97.3% vs 92.5%; specificity, 99.8% vs 99.8%). The average subjective image quality score was 4.3 {+-} 0.7. The mean effective dose was 0.38 {+-} 0.09 mSv. Prospective ECG-triggering DSCT angiography with a very low effective radiation dose allows the accurate diagnosis of anomalies in infants and children with complex CHD compared with TTE. It has great promise to become a commonly used second-line technique for complex CHD. (orig.)

  15. The value of low-dose prospective ECG-gated dual-source CT angiography in the diagnosis of coarctation of the aorta in infants and children

    Energy Technology Data Exchange (ETDEWEB)

    Nie, P. [Shandong Provincial Key Laboratory of Diagnosis and Treatment of Cardio-Cerebral Vascular Diseases, Shandong Medical Imaging Research Institute, Shandong University, Jinan, Shandong (China); Wang, X., E-mail: wxming369@yahoo.com.cn [Shandong Provincial Key Laboratory of Diagnosis and Treatment of Cardio-Cerebral Vascular Diseases, Shandong Medical Imaging Research Institute, Shandong University, Jinan, Shandong (China); Cheng, Z.; Duan, Y.; Ji, X. [Shandong Provincial Key Laboratory of Diagnosis and Treatment of Cardio-Cerebral Vascular Diseases, Shandong Medical Imaging Research Institute, Shandong University, Jinan, Shandong (China); Chen, J. [CT Research Collaboration, Siemens, Beijing (China); Zhang, H. [Department of Cardiovascular Surgery, Shandong Provincial Hospital, Jinan, Shandong (China)

    2012-08-15

    Aim: To investigate the value of prospective electrocardiogram (ECG)-gated dual-source computed tomography (DSCT) in the diagnosis of coarctation of the aorta (CoA). Materials and methods: Seventeen patients clinically suspected of having CoA underwent prospective ECG-gated DSCT angiography and transthoracic echocardiography (TTE). Surgery was performed in all patients. The diagnostic accuracy of DSCT angiography and TTE was compared with the surgical findings as the reference standard. Image quality was evaluated using a five-point scale. Effective radiation dose was calculated from the dose-length product (DLP). Results: CoA was diagnosed in 17 patients by DSCT angiography and in 16 patients by TTE. A total of 46 separate cardiovascular abnormalities were confirmed by surgical findings. The diagnostic accuracy of DSCT angiography and TTE was 96.32% and 97.06%, respectively. There was no significant difference in the diagnostic accuracy between DSCT angiography and TTE ({chi}{sup 2} = 0, p > 0.05). The mean score of image quality was 4.2 {+-} 0.8. The mean effective dose was 0.69 {+-} 0.09 mSv. Conclusion: Prospective ECG-gated DSCT with a low radiation dose is a valuable technique in the diagnosis of CoA in infants and children.

  16. Diagnostic value of ECG-gated multidetector computed tomography in the early phase of suspected acute myocarditis. A preliminary comparative study with cardiac MRI

    Energy Technology Data Exchange (ETDEWEB)

    Dambrin, Gregoire; Caussin, Christophe; Lancelin, Bernard; Paul, Jean F. [Centre Chirurgical Marie Lannelongue, Departments of Cardiology and Radiology, Le Plessis Robinson (France); Laissy, Jean P.; Serfaty, Jean M. [AP-HP, Hospital Bichat, Department of Radiology, Paris (France)

    2007-02-15

    The aim of the study was to determine the potential diagnostic value of contrast-enhanced echocardiogram (ECG)-gated multidetector computed tomography (MDCT) in the setting of suspected acute myocarditis compared with contrast-enhanced magnetic resonance imaging (MRI). The study group consisted of 12 consecutive patients admitted for suspected acute myocarditis less than 10 days after onset of symptoms. All patients had clinical, electrocardiographic signs, and laboratory findings consistent with the diagnosis. All patients but one (severe claustrophobia) underwent cardiac MRI using T1-weighted delayed-enhancement images after injection of gadolinium. ECG-gated MDCT was performed in all patients and included a first-pass contrast-enhanced acquisition and a delayed acquisition. MRI revealed abnormal focal or multifocal myocardial enhancement and confirmed the diagnosis in 11 patients. The first-pass MDCT acquisition showed homogenous left-ventricle contrast enhancement and absence of coronary stenosis in all patients. Delayed MDCT acquisition, performed 5 min later without reinjection of contrast medium revealed multiple areas of myocardial hyperenhancement in a focal or a multifocal pattern (six and six patients, respectively). Extent and location of hyperenhancement at MDCT correlated well with that observed at MR examination for all 11 patients evaluated by both techniques (r=0.9167, p=0.0004). These preliminary results show that ECG-gated MDCT could be a useful alternative noninvasive diagnostic test in the early phase of acute myocarditis. (orig.)

  17. 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.

  18. Beat-to-beat heart rate detection in multi-lead abdominal fetal ECG recordings.

    Science.gov (United States)

    Peters, C H L; van Laar, J O E H; Vullings, R; Oei, S G; Wijn, P F F

    2012-04-01

    Reliable monitoring of fetal condition often requires more information than is provided by cardiotocography, the standard technique for fetal monitoring. Abdominal recording of the fetal electrocardiogram may offer valuable additional information, but unfortunately is troubled by poor signal-to-noise ratios during certain parts of pregnancy. To increase the usability of abdominal fetal ECG recordings, an algorithm was developed that enhances fetal QRS complexes in these recordings and thereby provides a promising method for detecting the beat-to-beat fetal heart rate in recordings with poor signal-to-noise ratios. The method was evaluated on generated recordings with controlled signal-to-noise ratios and on actual recordings that were performed in clinical practice and were annotated by two independent experts. The evaluation on the generated signals demonstrated excellent results (sensitivity of 0.98 for SNR≥1.5). Only for SNRheart rate detection exceeded 2 ms, which may still suffice for cardiotocography but is unacceptable for analysis of the beat-to-beat fetal heart rate variability. The sensitivity and positive predictive value of the method in actual recordings were reduced to approximately 90% for SNR≤2.4, but were excellent for higher signal-to-noise ratios.

  19. Assessment of left ventricular performance by ECG-gated SPECT. Comparison with magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Tadamura, Eiji; Inubushi, Masayuki; Kubo, Shigeto; Matsumoto, Keiichi; Yokoyama, Hiroshi; Fujita, Toru; Konishi, Junji [Kyoto Univ. (Japan). Faculty of Medicine

    1999-10-01

    In the measurement of a left ventricular volume, MIBI-QGS was compared with MRI. Because it became clear by the experiment using phantom that a volume calculated with QGS was smaller than the actual volume, data of clinical study were corrected. Subjects were 20 patients with coronary artery disease. Fourteen patients had anamnesis of myocardial infarct. ECG-gated SPECT was performed one hour after intravenous injection of MIBI (600 MBq) in rest. End diastolic volume (EDV), end systolic volume (ESV) and ejection fraction (EF) were calculated using QGS. Cine-MR image was obtained by using MR system of 1.5 Tesla within 1 week after SPECT. A condition was as follows; segmented k-space gradient echo with view sharing, TR=11 ms, TE=1.4 ms, flip angle 20 degree, field of view 32 cm, matrix 256 x 196, 8 lines per segment. LVEF, ESV and EF were analysed by Bland-Altman method, and the difference between MIBI-gated-SPECT and MRI was no problem. Horizontal dislocation image and vertical major axis dislocation image were provided. Minor axis crossing images of 10-12 slice were also filmed in order to cover all left ventricles. As a result, availability of MIBI-QGS became clear. Some factors which produces the measurement error are examined. (K.H.)

  20. Soft, Comfortable Polymer Dry Electrodes for High Quality ECG and EEG Recording

    Directory of Open Access Journals (Sweden)

    Yun-Hsuan Chen

    2014-12-01

    Full Text Available Conventional gel electrodes are widely used for biopotential measurements, despite important drawbacks such as skin irritation, long set-up time and uncomfortable removal. Recently introduced dry electrodes with rigid metal pins overcome most of these problems; however, their rigidity causes discomfort and pain. This paper presents dry electrodes offering high user comfort, since they are fabricated from EPDM rubber containing various additives for optimum conductivity, flexibility and ease of fabrication. The electrode impedance is measured on phantoms and human skin. After optimization of the polymer composition, the skin-electrode impedance is only ~10 times larger than that of gel electrodes. Therefore, these electrodes are directly capable of recording strong biopotential signals such as ECG while for low-amplitude signals such as EEG, the electrodes need to be coupled with an active circuit. EEG recordings using active polymer electrodes connected to a clinical EEG system show very promising results: alpha waves can be clearly observed when subjects close their eyes, and correlation and coherence analyses reveal high similarity between dry and gel electrode signals. Moreover, all subjects reported that our polymer electrodes did not cause discomfort. Hence, the polymer-based dry electrodes are promising alternatives to either rigid dry electrodes or conventional gel electrodes.

  1. Soft, Comfortable Polymer Dry Electrodes for High Quality ECG and EEG Recording

    Science.gov (United States)

    Chen, Yun-Hsuan; de Beeck, Maaike Op; Vanderheyden, Luc; Carrette, Evelien; Mihajlović, Vojkan; Vanstreels, Kris; Grundlehner, Bernard; Gadeyne, Stefanie; Boon, Paul; Van Hoof, Chris

    2014-01-01

    Conventional gel electrodes are widely used for biopotential measurements, despite important drawbacks such as skin irritation, long set-up time and uncomfortable removal. Recently introduced dry electrodes with rigid metal pins overcome most of these problems; however, their rigidity causes discomfort and pain. This paper presents dry electrodes offering high user comfort, since they are fabricated from EPDM rubber containing various additives for optimum conductivity, flexibility and ease of fabrication. The electrode impedance is measured on phantoms and human skin. After optimization of the polymer composition, the skin-electrode impedance is only ∼10 times larger than that of gel electrodes. Therefore, these electrodes are directly capable of recording strong biopotential signals such as ECG while for low-amplitude signals such as EEG, the electrodes need to be coupled with an active circuit. EEG recordings using active polymer electrodes connected to a clinical EEG system show very promising results: alpha waves can be clearly observed when subjects close their eyes, and correlation and coherence analyses reveal high similarity between dry and gel electrode signals. Moreover, all subjects reported that our polymer electrodes did not cause discomfort. Hence, the polymer-based dry electrodes are promising alternatives to either rigid dry electrodes or conventional gel electrodes. PMID:25513825

  2. Efficient noise cancellers for ECG signal enhancement for telecardiology applications

    Directory of Open Access Journals (Sweden)

    Nagesh MANTRAVADI

    2016-12-01

    Full Text Available In this paper some effective noise cancellers were proposed using the variants of Least Mean Fourth (LMF Algorithm to remove the artifacts that occur during the acquisition stage of an ECG signal. In order to accelerate the performance of the LMF algorithm we introduce data normalization in weight update process. This results two variants of LMF algorithm, called normalized LMF (NLMF and global NLMF (GNLMF algorithms. Further, to minimize their computational complexity and improve convergence characteristics, tracking ability, filtering capability we apply signum and block processing on the two versions of normalized algorithms. Both the two treatments results six more algorithms. Using these algorithms we develop various adaptive noise cancellers (ANCs. These ANCs are tested with the help of standard MIT-BIH arrhythmia database for various records. The Signal to noise ratio, Excess Mean Square Error and misadjustment are taken as performances measures to analyze the performance of proposed methods. These ANCs exhibit improved performance over the LMF based ANC.

  3. The RR interval spectrum, the ECG signal and aliasing

    CERN Document Server

    Gersten, A; Ronen, A; Cassuto, Y

    1999-01-01

    A reliable spectral analysis requires sampling rate at least twice as large as the frequency bound, otherwise the analysis will be unreliable and plagued with aliasing distortions. The RR samplings do not satisfy the above requirements and therefore their spectral analysis might be unreliable. In order to demonstrate the feasibility of aliasing in RR spectral analysis, we have done an experiment which have shown clearly how the aliasing was developed. In the experiments, one of us (A.G) had kept his high breathing rate constant with the aid of metronome for more than 5 minutes. The breathing rate was larger than one-half the heart rate. Very accurate results were obtained and the resulting aliasing well understood. To our best knowledge this is the first controlled experiment of this kind coducted on humans. We compared the RR spectral analysis with the spectrum of the ECG signals from which the RR intervals were extracted. In the significant for RR analysis frequencies (below one-half Hertz) significant diff...

  4. 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.

  5. Human ECG indicators for fast screening and evaluation

    Science.gov (United States)

    Maciejewski, Marcin; DzierŻak, RóŻa; Surtel, Wojciech; Saran, Tomasz

    2016-09-01

    Telemedical system design and implementation requires numerous steps. It is necessary to evaluate the operation of algorithms responsible for analysis and detection of life-threatening situations. By performing ECG analysis it is possible to obtain information about the overall patient health condition as well as detailed information about the circulatory system condition. To achieve that goal one must gather, filter and process data. Data was gathered using a purposely built device from a group of four volunteers. Available data set was processed to obtain information about the patients condition. Pan-Tompkins algorithm was used to detect R peaks and calculate heart rhythm. Afterward the rest of parameters were extracted in time domain using windowed peak detection and polynomial estimation. The parameters were calculated as delays between appropriate points in the signal. The method proved to be able to extract parameters in some of the cases, and proved limited effectiveness in situations where physical activity was significant. It was nevertheless possible to eliminate noise from the mains, the trend and higher frequency noise Further improvements need to be introduced to increase the method's robustness in the presence of significant muscle noise.

  6. 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.

  7. Treatment of anestrous Nili-Ravi buffaloes using eCG and CIDR protocols

    Institute of Scientific and Technical Information of China (English)

    Zahid Naseer; Ejaz Ahmad; Nemat Ullah; Muhammad Yaqoob; Zeeshan Akbar

    2013-01-01

    Objective: To determine the effect of equine chorionic gonadotropin (eCG) and controlled internal drug releasing (CIDR) on estrus response, ovulation and pregnancy rate in Nili-Ravi buffaloes under field condition. Methods: Twenty anestrous buffaloes with more than 150 days postpartum were used in this study. To confirm anestrous condition, ovarian status and serum progesterone concentration were determined before the start of study. Buffaloes were randomly divided into eCG (n=10) and CIDR (n=10) groups. eCG group were treated with eCG (Chronogest 1000 I.U. i.m.), while CIDR group received CIDR devices for 7 days. All buffaloes in CIDR group were injected PGF2α (0.25 ug/mL; 2 mL; i.m.) one day before CIDR removal. Buffaloes were observed for estrus visually and were inseminated with frozen-thawed semen at detected estrus. Ovulation was confirmed by presence of CL 12 day post AI. Pregnancy diagnosis was done 50 days post AI. Results: Estrus response, ovulation rate and pregnancy rate were similar (P>0.05) among eCG and CIDR groups (90% vs. 80%; 78% vs. 75% and 50% vs. 60% respectively). Conclusion: It is concluded that both CIDR and eCG protocols are effective and promising remedies for the anestrous buffaloes under commercial as well as under field conditions.

  8. An estimate of the dispersion of repolarization times based on a biophysical model of the ECG.

    Science.gov (United States)

    Sassi, Roberto; Mainardi, Luca T

    2011-12-01

    Temporal heterogeneity of ventricular repolarization is a key quantity for the development of ventricular reentrant arrhythmia. In this paper, we introduce the V-index, a novel ECG-based estimator of the standard deviation of ventricular myocytes' repolarization times s(ϑ). Differently from other ECG metrics of repolarization heterogeneity, the V-index was derived from the analysis of a biophysical model of the ECG, where repolarization is described by the dominant T-wave (DTW) paradigm. The model explains the shape of T-waves in each lead as a projection of a main waveform (the DTW) and its derivatives weighted by scalars, the lead factors. A mathematical formula is derived to link the heterogeneity of ventricular repolarization s(ϑ) and the V-index. The formula was verified using synthetic 12-lead ECGs generated with a direct electrophysiological model for increasing values of s(ϑ) (in the range 20-70 ms). A linear relationship between the V-index and s(ϑ) was observed, V ≈ 0.675 s(ϑ) + 1.8 ms (R(2) = 0.9992). Finally, 68 ECGs from the E-OTH-12-0068-010 database of the Telemetric and Holter ECG Warehouse were analyzed. The V-index coherently increased after sotalol administration, a drug known to have QT-prolonging potential (p < 0.001).

  9. CNT/PDMS composite flexible dry electrodes for long-term ECG monitoring.

    Science.gov (United States)

    Jung, Ha-Chul; Moon, Jin-Hee; Baek, Dong-Hyun; Lee, Jae-Hee; Choi, Yoon-Young; Hong, Joung-Sook; Lee, Sang-Hoon

    2012-05-01

    We fabricated a carbon nanotube (CNT)/ polydimethylsiloxane (PDMS) composite-based dry ECG electrode that can be readily connected to conventional ECG devices, and showed its long-term wearable monitoring capability and robustness to motion and sweat. While the dispersion of CNTs in PDMS is challenging, we optimized the process to disperse untreated CNTs within PDMS by mechanical force only. The electrical and mechanical characteristics of the CNT/PDMS electrode were tested according to the concentration of CNTs and its thickness. The performances of ECG electrodes were evaluated by using 36 types of electrodes which were fabricated with different concentrations of CNTs, and with a differing diameter and thickness. The ECG signals were obtained by using electrodes of diverse sizes to observe the effects of motion and sweat, and the proposed electrode was shown to be robust to both factors. The CNT concentration and diameter of the electrodes were critical parameters in obtaining high-quality ECG signals. The electrode was shown to be biocompatible from the cytotoxicity test. A seven-day continuous wearability test showed that the quality of the ECG signal did not degrade over time, and skin reactions such as itching or erythema were not observed. This electrode could be used for the long-term measurement of other electrical biosignals for ubiquitous health monitoring including EMG, EEG, and ERG.

  10. Wavelet-Based ECG Steganography for Protecting Patient Confidential Information in Point-of-Care Systems.

    Science.gov (United States)

    Ibaida, Ayman; Khalil, Ibrahim

    2013-12-01

    With the growing number of aging population and a significant portion of that suffering from cardiac diseases, it is conceivable that remote ECG patient monitoring systems are expected to be widely used as point-of-care (PoC) applications in hospitals around the world. Therefore, huge amount of ECG signal collected by body sensor networks from remote patients at homes will be transmitted along with other physiological readings such as blood pressure, temperature, glucose level, etc., and diagnosed by those remote patient monitoring systems. It is utterly important that patient confidentiality is protected while data are being transmitted over the public network as well as when they are stored in hospital servers used by remote monitoring systems. In this paper, a wavelet-based steganography technique has been introduced which combines encryption and scrambling technique to protect patient confidential data. The proposed method allows ECG signal to hide its corresponding patient confidential data and other physiological information thus guaranteeing the integration between ECG and the rest. To evaluate the effectiveness of the proposed technique on the ECG signal, two distortion measurement metrics have been used: the percentage residual difference and the wavelet weighted PRD. It is found that the proposed technique provides high-security protection for patients data with low (less than 1%) distortion and ECG data remain diagnosable after watermarking (i.e., hiding patient confidential data) and as well as after watermarks (i.e., hidden data) are removed from the watermarked data.

  11. ECG Database Applicable for Development and Testing of Pace Detection Algorithms

    Directory of Open Access Journals (Sweden)

    Irena Jekova

    2014-12-01

    Full Text Available This paper presents an ECG database, named 'PacedECGdb' (available at http://biomed.bas.bg/bioautomation/2014/vol_18.4/files/PacedECGdb.zip, which contains different arrhythmias generated by HKP (Heidelberger Praxisklinik simulator, combined with artificially superimposed pacing pulses that cover the wide ranges of rising edge (from <10 µs to 100 µs and total pulse durations (from 100 µs to 2 ms and correspond to various pacemaker modes. It involves a total number of 1404 recordings - 780 representing 'pure' ECG with pacing pulses and 624 that comprise paced ECGs corrupted by tremor. The signals are recorded with 9.81 µV/LSB amplitude resolution at 128 kHz sampling rate in order to preserve the steep raising and trailing edges of the pace pulses. To the best of our knowledge, 'PacedECGdb' is the first publicly available paced ECG database. It could be used for development and testing of methods for pace detection in the ECG. The existence of ECGs corrupted by tremor (the only physiological noise that could compromise the methods for pacing pulses detection is an advantage, since such signals could be applied to define the signal-to-noise level for correct operation of the algorithm, or for improvement of the noise immunity of a method that is under development. The open access of the database makes it suitable for comparative studies including different algorithms.

  12. Heart rate detection in low amplitude non-invasive fetal ECG recordings.

    Science.gov (United States)

    Peters, Chris; Vullings, Rik; Bergmans, Jan; Oei, Guid; Wijn, Pieter

    2006-01-01

    Multi-electrode electrical measurements on the maternal abdomen may provide a valuable alternative to standard fetal monitoring. Removal of the maternal ECG from these recordings by means of subtracting a weighted linear combination of segments from preceding maternal ECG complexes, results in fetal ECG traces from which the fetal heart rate can be determined. Unfortunately, these traces often contain too much noise to determine the heart rate by R-peak detection. To overcome this limitation, an algorithm has been developed that calculates the heart rate based on cross-correlation. To validate the algorithm, noise was added to a fetal scalp ECG recording to simulate low amplitude abdominal recordings. Heart rates calculated by the algorithm were compared to the heart rates from the original scalp ECG. For simulated signals with a signal to noise ratio of 2, the coefficient of correlation was 0.99 (pheart rate, multi-electrode electrical measurements on the maternal abdomen now can be used for fetal monitoring in relatively early stages of pregnancy or other situations where ECG amplitudes are low or noise levels are high.

  13. 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.

  14. Artificial neural network-based classification of body movements in ambulatory ECG signal.

    Science.gov (United States)

    Darji, Sachin T; Kher, Rahul K

    2013-11-01

    Abstract Ambulatory ECG monitoring provides electrical activity of the heart when a person is involved in doing normal routine activities. Thus, the recorded ECG signal consists of cardiac signal along with motion artifacts introduced due to a person's body movements during routine activities. Detection of motion artifacts due to different physical activities might help in further cardiac diagnosis. Ambulatory ECG signal analysis for detection of various motion artifacts using adaptive filtering approach is addressed in this paper. We have used BIOPAC MP 36 system for acquiring ECG signal. The ECG signals of five healthy subjects (aged between 22-30 years) were recorded while the person performed various body movements like up and down movement of the left hand, up and down movement of the right hand, waist twisting movement while standing and change from sitting down on a chair to standing up movement in lead I configuration. An adaptive filter-based approach has been used to extract the motion artifact component from the ambulatory ECG signal. The features of motion artifact signal, extracted using Gabor transform, have been used to train the artificial neural network (ANN) for classifying body movements.

  15. A configurable and low-power mixed signal SoC for portable ECG monitoring applications.

    Science.gov (United States)

    Kim, Hyejung; Kim, Sunyoung; Van Helleputte, Nick; Artes, Antonio; Konijnenburg, Mario; Huisken, Jos; Van Hoof, Chris; Yazicioglu, Refet Firat

    2014-04-01

    This paper describes a mixed-signal ECG System-on-Chip (SoC) that is capable of implementing configurable functionality with low-power consumption for portable ECG monitoring applications. A low-voltage and high performance analog front-end extracts 3-channel ECG signals and single channel electrode-tissue-impedance (ETI) measurement with high signal quality. This can be used to evaluate the quality of the ECG measurement and to filter motion artifacts. A custom digital signal processor consisting of 4-way SIMD processor provides the configurability and advanced functionality like motion artifact removal and R peak detection. A built-in 12-bit analog-to-digital converter (ADC) is capable of adaptive sampling achieving a compression ratio of up to 7, and loop buffer integration reduces the power consumption for on-chip memory access. The SoC is implemented in 0.18 μm CMOS process and consumes 32 μ W from a 1.2 V while heart beat detection application is running, and integrated in a wireless ECG monitoring system with Bluetooth protocol. Thanks to the ECG SoC, the overall system power consumption can be reduced significantly.

  16. Real-time CHF detection from ECG signals using a novel discretization method.

    Science.gov (United States)

    Orhan, Umut

    2013-10-01

    This study proposes a new method, equal frequency in amplitude and equal width in time (EFiA-EWiT) discretization, to discriminate between congestive heart failure (CHF) and normal sinus rhythm (NSR) patterns in ECG signals. The ECG unit pattern concept was introduced to represent the standard RR interval, and our method extracted certain features from the unit patterns to classify by a primitive classifier. The proposed method was tested on two classification experiments by using ECG records in Physiobank databases and the results were compared to those from several previous studies. In the first experiment, an off-line classification was performed with unit patterns selected from long ECG segments. The method was also used to detect CHF by real-time ECG waveform analysis. In addition to demonstrating the success of the proposed method, the results showed that some unit patterns in a long ECG segment from a heart patient were more suggestive of disease than the others. These results indicate that the proposed approach merits additional research.

  17. 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

    2017-01-01

    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.

  18. Investigations of sensitivity and resolution of ECG and MCG in a realistically shaped thorax model.

    Science.gov (United States)

    Mäntynen, Ville; Konttila, Teijo; Stenroos, Matti

    2014-12-07

    Solving the inverse problem of electrocardiography (ECG) and magnetocardiography (MCG) is often referred to as cardiac source imaging. Spatial properties of ECG and MCG as imaging systems are, however, not well known. In this modelling study, we investigate the sensitivity and point-spread function (PSF) of ECG, MCG, and combined ECG+MCG as a function of source position and orientation, globally around the ventricles: signal topographies are modelled using a realistically-shaped volume conductor model, and the inverse problem is solved using a distributed source model and linear source estimation with minimal use of prior information. The results show that the sensitivity depends not only on the modality but also on the location and orientation of the source and that the sensitivity distribution is clearly reflected in the PSF. MCG can better characterize tangential anterior sources (with respect to the heart surface), while ECG excels with normally-oriented and posterior sources. Compared to either modality used alone, the sensitivity of combined ECG+MCG is less dependent on source orientation per source location, leading to better source estimates. Thus, for maximal sensitivity and optimal source estimation, the electric and magnetic measurements should be combined.

  19. Deployment of an Advanced Electrocardiographic Analysis (A-ECG) to Detect Cardiovascular Risk in Career Firefighters

    Science.gov (United States)

    Dolezal, B. A.; Storer, T. W.; Abrazado, M.; Watne, R.; Schlegel, T. T.; Batalin, M.; Kaiser, W.; Smith, D. L.; Cooper, C. B.

    2011-01-01

    INTRODUCTION Sudden cardiac death is the leading cause of line of duty death among firefighters, accounting for approximately 45% of fatalities annually. Firefighters perform strenuous muscular work while wearing heavy, encapsulating personal protective equipment in high ambient temperatures, under chaotic and emotionally stressful conditions. These factors can precipitate sudden cardiac events like myocardial infarction, serious dysrhythmias, or cerebrovascular accidents in firefighters with underlying cardiovascular disease. Screening for cardiovascular risk factors is recommended but not always followed in this population. PHASER is a project charged with identifying and prioritizing risk factors in emergency responders. We have deployed an advanced ECG (A-ECG) system developed at NASA for improved sensitivity and specificity in the detection of cardiac risk. METHODS Forty-four professional firefighters were recruited to perform comprehensive baseline assessments including tests of aerobic performance and laboratory tests for fasting lipid profiles and glucose. Heart rate and conventional 12-lead ECG were obtained at rest and during incremental treadmill exercise testing (XT). In addition, a 5-min resting 12-lead A-ECG was obtained in a subset of firefighters (n=18) and transmitted over a secure networked system to a physician collaborator at NASA for advanced-ECG analysis. This A-ECG system has been proven, using myocardial perfusion and other imaging, to accurately identify a number of cardiac pathologies including coronary artery disease (CAD), left ventricular hypertrophy, hypertrophic cardiomyopathy, non-ischemic cardiomyopathy, and ischemic cardiomyopathy. RESULTS Subjects mean (SD) age was 43 (8) years, weight 91 (13) kg, and BMI of 28 (3) kg/square meter. Maximum oxygen uptake (VO2max) was 39 (9) ml/kg/min. This compares with the 45th %ile in healthy reference values and a recommended standard of 42 ml/kg/min for firefighters. The metabolic threshold (VO

  20. A reversed-phase HPLC-UV assay for simultaneous analysis of EGCG and ECG of tea polyphenols in rat plasma

    Institute of Scientific and Technical Information of China (English)

    FU Ting; LIANG Jun; HAN Guo-zhu; L(U) Li; LI Nan

    2008-01-01

    pharmacokinetically behaved as the two-compartment model and first-order kinetics, with t1/2β 122.9 min and 59.2 min, Vd 7.96 L·kg-1 and 1.22 L·kg-1, CL 0.044 L·kg-1·min-1 and 0.015 L·kg-1·min-1 for EGCG and ECG, respectively. Conclusions The method developed in the present study is highly specific, precise, accurate, and suitable for the non-clinical pharmacokinetie study of the TP in rats.

  1. Prospectively ECG-triggered sequential dual-source coronary CT angiography in patients with atrial fibrillation: comparison with retrospectively ECG-gated helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Lei; Yang, Lin; Zhang, Zhaoqi [Capital Medical University, Department of Radiology, Beijing Anzhen Hospital, Beijing (China); Wang, Yining; Jin, Zhengyu [Chinese Academy of Medical Sciences, Department of Radiology, Peking Union Medical College Hospital, Beijing (China); Zhang, Longjiang; Lu, Guangming [Nanjing University, Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing, Jiangsu (China)

    2013-07-15

    To investigate the feasibility of applying prospectively ECG-triggered sequential coronary CT angiography (CCTA) to patients with atrial fibrillation (AF) and evaluate the image quality and radiation dose compared with a retrospectively ECG-gated helical protocol. 100 patients with persistent AF were enrolled. Fifty patients were randomly assigned to a prospective protocol and the other patients to a retrospective protocol using a second-generation dual-source CT (DS-CT). Image quality was evaluated using a four-point grading scale (1 = excellent, 2 = good, 3 = moderate, 4 = poor) by two reviewers on a per-segment basis. The coronary artery segments were considered non-diagnostic with a quality score of 4. The radiation dose was evaluated. Diagnostic segment rate in the prospective group was 99.4 % (642/646 segments), while that in the retrospective group was 96.5 % (604/626 segments) (P < 0.001). Effective dose was 4.29 {+-} 1.86 and 11.95 {+-} 5.34 mSv for each of the two protocols (P < 0.001), which was a 64 % reduction in the radiation dose for prospective sequential imaging compared with retrospective helical imaging. In AF patients, prospectively ECG-triggered sequential CCTA is feasible using second-generation DS-CT and can decrease >60 % radiation exposure compared with retrospectively ECG-gated helical imaging while improving diagnostic image quality. (orig.)

  2. The chaos and order in human ECG under the influence of the external perturbations

    Science.gov (United States)

    Ragulskaya, Maria; Valeriy, Pipin

    The results of the many-year telecommunication heliomedical monitoring "Heliomed" show, that space weather and geophysical factor variations serve as a training factor for the adaptation-resistant member of the human population. Here we discuss the specific properties of the human ECG discovered in our experiment. The program "Heliomed" is carried out simultaneously at the different geographical areas that cover the different latitudes. The daily registered param-eters include: the psycho-emotional tests and the 1-st lead ECG, the arterial pressure, the variability cardiac contraction, the electric conduction of bioactive points on skin. The results time series compared with daily values of space weather and geomagnetic parameters. The analysis of ECG signal proceeds as follows. At first step we construct the ECG embedding into 3D phase space using the first 3 Principal Components of the ECG time series. Next, we divide ECG on the separate cycles using the maxima of the ECG's QRS complex. Then, we filter out the non-typical ECG beats by means of the Housdorff distance. Finally, we average the example of the ECG time series along the reference trajectory and study of the dynamical characteristics of the averaged ECG beat. It is found, that the ECG signal embeded in 3D phase space can be considered as a mix of a few states. At the rest, the occurrence of the primary ECG state compare to additional ones is about 8:2. The occurrence of the primary state increases after the stress. The main effect of the external perturbation is observed in structural change of the cardio-cycle and not in the variability of the R-R interval. The num-ber of none-typical cycles increase during an isolated magnetic storm. At the all monitoring centers participating experiment the same type of changes in the cardiac activity parameters is detected to go nearly simultaneously during an isolated magnetic storm. To understand the origin of the standard cardio-cycle changes we use the dynamical

  3. QRS classification and spatial combination for robust heart rate detection in low-quality fetal ECG recordings.

    Science.gov (United States)

    Warmerdam, G; Vullings, R; Van Pul, C; Andriessen, P; Oei, S G; Wijn, P

    2013-01-01

    Non-invasive fetal electrocardiography (ECG) can be used for prolonged monitoring of the fetal heart rate (FHR). However, the signal-to-noise-ratio (SNR) of non-invasive ECG recordings is often insufficient for reliable detection of the FHR. To overcome this problem, source separation techniques can be used to enhance the fetal ECG. This study uses a physiology-based source separation (PBSS) technique that has already been demonstrated to outperform widely used blind source separation techniques. Despite the relatively good performance of PBSS in enhancing the fetal ECG, PBSS is still susceptible to artifacts. In this study an augmented PBSS technique is developed to reduce the influence of artifacts. The performance of the developed method is compared to PBSS on multi-channel non-invasive fetal ECG recordings. Based on this comparison, the developed method is shown to outperform PBSS for the enhancement of the fetal ECG.

  4. QT dispersion on ECG Holter monitoring and risk of ventricular arrhythmias in patients with dilated cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Polyxeni Garyfallidis

    2010-05-01

    Full Text Available Background. QT dispersion (QTd is increased in patients with dilated cardiomyopathy. Increased QTd has been associated with the risk of sudden death. We studied: a the relation between QTd on 12-lead ECG and QTd-ECG Holter; b the relation between QTd apex (QTda and QTd end (QTde on ECG Holter and the risk of ventricular arrhythmias in patients with dilated cardiomyopathy. Methods and Results. 65 patients with dilated cardiomyopathy (33 idiopathic and 32 post-ischemic etiology; NYHA II-III were studied. We divided the patients into: Group A -patients with not-sustained ventricular arrhythmias-; and Group B -patients without arrhythmias-. A significant direct correlation between QTd calculated from 12-lead ECG and from ECG Holter was found in all patients. QTda/24h was not significantly different in the two groups (Gr.A 59.9±7.8 msec vs Gr.B 53.6±8.4 msec p=ns while QTde/24h was significantly higher in Group A (Gr.A 81.9±5.9 msec vs Gr.B 44.5±6.8 msec; p<0.005. In post-ischemic etiology (32 pts; 17 with arrhythmias the correlation between QTde/24h and ventricular arrhythmias was confirmed (Gr.A 81.4±7.8 msec vs Gr.B 42.6±6.2 msec p<0.002. Conclusions. ECG Holter recordings can evaluate QTd as well as the QTd on 12-lead ECG. An increased QTde/24h seems to be correlated with the occurence of ventricular arrhythmias in patients with dilated cardiomyopathy and can then be a useful tool to select patients at high risk for sudden death.

  5. ECG-gated computed tomography: a new role for patients with suspected aortic prosthetic valve endocarditis

    Energy Technology Data Exchange (ETDEWEB)

    Fagman, Erika; Flinck, Agneta; Lamm, Carl [Sahlgrenska University Hospital, Department of Radiology, Gothenburg (Sweden); Perrotta, Sossio [Sahlgrenska University Hospital, Department of Cardiovascular Surgery and Anaesthesia, Gothenburg (Sweden); Bech-Hanssen, Odd [Sahlgrenska University Hospital, Department of Clinical Physiology, Gothenburg (Sweden); Sahlgrenska University Hospital, Department of Cardiology, Gothenburg (Sweden); Olaison, Lars [Sahlgrenska University Hospital, Department of Infectious Diseases, Gothenburg (Sweden); Svensson, Gunnar [Sahlgrenska University Hospital, Department of Cardiovascular Surgery and Anaesthesia, Gothenburg (Sweden); The Sahlgrenska Academy at the University of Gothenburg, Department of Molecular and Clinical Medicine, Institute of Medicine, Gothenburg (Sweden)

    2012-11-15

    The aim of this prospective study was to investigate the agreement in findings between ECG-gated CT and transoesophageal echocardiography (TEE) in patients with aortic prosthetic valve endocarditis (PVE). Twenty-seven consecutive patients with PVE underwent 64-slice ECG-gated CT and TEE and the results were compared. Imaging was compared with surgical findings (surgery was performed in 16 patients). TEE suggested the presence of PVE in all patients [thickened aortic wall (n = 17), vegetation (n = 13), abscess (n = 16), valvular dehiscence (n = 10)]. ECG-gated CT was positive in 25 patients (93 %) [thickened aortic wall (n = 19), vegetation (n = 7), abscess (n = 18), valvular dehiscence (n = 7)]. The strength of agreement [kappa (95 % CI)] between ECG-gated CT and TEE was very good for thickened wall [0.83 (0.62-1.0)], good for abscess [0.68 (0.40-0.97)] and dehiscence [0.75 (0.48-1.0)], and moderate for vegetation [0.55 (0.26-0.88)]. The agreement was good between surgical findings (abscess, vegetation and dehiscence) and imaging for ECG-gated CT [0.66 (0.49-0.87)] and TEE [0.79 (0.62-0.96)] and very good for the combination of ECG-gated CT and TEE [0.88 (0.74-1.0)]. Our results indicate that ECG-gated CT has comparable diagnostic performance to TEE and may be a valuable complement in the preoperative evaluation of patients with aortic PVE. (orig.)

  6. [Normal values of temporal parameters of ECG in children according to results of clinico-epidemiological study ECG-screening of children and adolescents in Russian federation].

    Science.gov (United States)

    Miklashevich, I M; Shkol'nikova, M A; Kalinin, L A; Abdullatipova, I V; Osokina, G G; Deev, A D; Blinova, A V; Drozdova, A I; Lebed'kova, S E; Muratov, R A; Verevkina, O N; Timukova, A K; Lunegova, E V; Kozlova, L V; Svintsova, L I; Khomiakova, O I; Ashcheulova, N L

    2009-01-01

    In order to obtain reliable information about time-domain ECG parameters in Russian children and to analyse their links with physiological changes the Project "ECG screening of children and adolescents of the Russian Federation" was carried out in 2003-2008. Time domain ECG parameters were studied in the representative sample of 5387 healthy individuals aged 0 to 18 years. In each age group, lower and upper limits of the norm for heart rate (HR), P wave, PQ and QRS intervals were defined as 2nd and 98th percentiles of their distribution. The equivalent limits of QT interval duration were defined as its 5th and 95th percentiles. Relationship between time domain parameters of pediatric ECG and HR was analyzed as well as relationship of these parameters with sex and age. The most important differences from prior pediatric studies completed 30 years ago were obtained for the heart rate limits. Among children aged 0 to 3, there was a tendency toward lowering of age-specific lower limits and elevation of age-specific upper limits. At ages older than 3 years, there was a tendency toward lowering of both the upper and the lower limits of HR. The newly obtained 2nd percentiles of the heart rate were lower than the known lower limits in nearly all ages. This indicates the necessity for revision of criteria of bradicardia in children. The present study showed that 5th and 95th percentiles of QTc interval (Bazett's formula) varied between 340 ms and 465 ms and were not significantly dependent on children's age and only for ages under 13 also on sex. Results of the study allowed to build age-specific ranges of norm for the time domain ECG parameters presented in a tabular form.

  7. ECG -6511心电图机常见故障的维修分析

    Institute of Scientific and Technical Information of China (English)

    李会菊

    2016-01-01

    ECG -6511心电图机作为重要的医疗设备需要具有良好的稳定性。本文从阐述 ECG -6511心电图机常见故障入手,对于 ECG -6511心电图机故障维修进行了分析。

  8. Extraction of fetal electrocardiogram (ECG) by extended state Kalman filtering and adaptive neuro-fuzzy inference system (ANFIS) based on single channel abdominal recording

    Indian Academy of Sciences (India)

    D Panigrahy; P K Sahu

    2015-06-01

    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 ECG extraction from one ECG signal recorded at the abdominal areas of the mother’s skin. The abdominal ECG is considered to be composite as it contains both mother’s and fetus’ ECG signals. We use extended Kalman filter framework to estimate the maternal component from abdominal ECG. The maternal component in the abdominal ECG signal is a nonlinear transformed version of maternal ECG. ANFIS network has been used to identify this nonlinear relationship, and to align the estimated maternal ECG signal with the maternal component in the abdominal ECG signal. Thus, we extract the fetal ECG component by subtracting the aligned version of the estimated maternal ECG from the abdominal signal. Our results demonstrate the effectiveness of the proposed technique in extracting the fetal ECG component from abdominal signal at different noise levels. The proposed technique is also validated on the extraction of fetal ECG from both actual abdominal recordings and synthetic abdominal recording.

  9. A Wearable Context-Aware ECG Monitoring System Integrated with Built-in Kinematic Sensors of the Smartphone

    Directory of Open Access Journals (Sweden)

    Fen Miao

    2015-05-01

    Full Text Available Continuously monitoring the ECG signals over hours combined with activity status is very important for preventing cardiovascular diseases. A traditional ECG holter is often inconvenient to carry because it has many electrodes attached to the chest and because it is heavy. This work proposes a wearable, low power context-aware ECG monitoring system integrated built-in kinetic sensors of the smartphone with a self-designed ECG sensor. The wearable ECG sensor is comprised of a fully integrated analog front-end (AFE, a commercial micro control unit (MCU, a secure digital (SD card, and a Bluetooth module. The whole sensor is very small with a size of only 58 × 50 × 10 mm for wearable monitoring application due to the AFE design, and the total power dissipation in a full round of ECG acquisition is only 12.5 mW. With the help of built-in kinetic sensors of the smartphone, the proposed system can compute and recognize user’s physical activity, and thus provide context-aware information for the continuous ECG monitoring. The experimental results demonstrated the performance of proposed system in improving diagnosis accuracy for arrhythmias and identifying the most common abnormal ECG patterns in different activities. In conclusion, we provide a wearable, accurate and energy-efficient system for long-term and context-aware ECG monitoring without any extra cost on kinetic sensor design but with the help of the widespread smartphone.

  10. [Research on ECG de-noising method based on ensemble empirical mode decomposition and wavelet transform using improved threshold function].

    Science.gov (United States)

    Ye, Linlin; Yang, Dan; Wang, Xu

    2014-06-01

    A de-noising method for electrocardiogram (ECG) based on ensemble empirical mode decomposition (EEMD) and wavelet threshold de-noising theory is proposed in our school. We decomposed noised ECG signals with the proposed method using the EEMD and calculated a series of intrinsic mode functions (IMFs). Then we selected IMFs and reconstructed them to realize the de-noising for ECG. The processed ECG signals were filtered again with wavelet transform using improved threshold function. In the experiments, MIT-BIH ECG database was used for evaluating the performance of the proposed method, contrasting with de-noising method based on EEMD and wavelet transform with improved threshold function alone in parameters of signal to noise ratio (SNR) and mean square error (MSE). The results showed that the ECG waveforms de-noised with the proposed method were smooth and the amplitudes of ECG features did not attenuate. In conclusion, the method discussed in this paper can realize the ECG denoising and meanwhile keep the characteristics of original ECG signal.

  11. An integrated healthcare information system for end-to-end standardized exchange and homogeneous management of digital ECG formats.

    Science.gov (United States)

    Trigo, Jesús Daniel; Martínez, Ignacio; Alesanco, Alvaro; Kollmann, Alexander; Escayola, Javier; Hayn, Dieter; Schreier, Günter; García, José

    2012-07-01

    This paper investigates the application of the enterprise information system (EIS) paradigm to standardized cardiovascular condition monitoring. There are many specifications in cardiology, particularly in the ECG standardization arena. The existence of ECG formats, however, does not guarantee the implementation of homogeneous, standardized solutions for ECG management. In fact, hospital management services need to cope with various ECG formats and, moreover, several different visualization applications. This heterogeneity hampers the normalization of integrated, standardized healthcare information systems, hence the need for finding an appropriate combination of ECG formats and a suitable EIS-based software architecture that enables standardized exchange and homogeneous management of ECG formats. Determining such a combination is one objective of this paper. The second aim is to design and develop the integrated healthcare information system that satisfies the requirements posed by the previous determination. The ECG formats selected include ISO/IEEE11073, Standard Communications Protocol for Computer-Assisted Electrocardiography, and an ECG ontology. The EIS-enabling techniques and technologies selected include web services, simple object access protocol, extensible markup language, or business process execution language. Such a selection ensures the standardized exchange of ECGs within, or across, healthcare information systems while providing modularity and accessibility.

  12. Online digital filter and QRS detector applicable in low resource ECG monitoring systems.

    Science.gov (United States)

    Tabakov, Serafim; Iliev, Ivo; Krasteva, Vessela

    2008-11-01

    The present work describes fast computation methods for real-time digital filtration and QRS detection, both applicable in autonomous personal ECG systems for long-term monitoring. Since such devices work under considerable artifacts of intensive body and electrode movements, the input filtering should provide high-quality ECG signals supporting the accurate ECG interpretation. In this respect, we propose a combined high-pass and power-line interference rejection filter, introducing the simple principle of averaging of samples with a predefined distance between them. In our implementation (sampling frequency of 250 Hz), we applied averaging over 17 samples distanced by 10 samples (Filter10x17), thus realizing a comb filter with a zero at 50 Hz and high-pass cut-off at 1.1 Hz. Filter10x17 affords very fast filtering procedure at the price of minimal computing resources. Another benefit concerns the small ECG distortions introduced by the filter, providing its powerful application in the preprocessing module of diagnostic systems analyzing the ECG morphology. Filter10x17 does not attenuate the QRS amplitude, or introduce significant ST-segment elevation/depression. The filter output produces a constant error, leading to uniform shifting of the entire P-QRS-T segment toward about 5% of the R-peak amplitude. Tests with standardized ECG signals proved that Filter10x17 is capable to remove very strong baseline wanderings, and to fully suppress 50 Hz interferences. By changing the number of the averaged samples and the distance between them, a filter design with different cut-off and zero frequency could be easily achieved. The real-time QRS detector is designed with simplified computations over single channel, low-resolution ECGs. It relies on simple evaluations of amplitudes and slopes, including history of their mean values estimated over the preceding beats, smart adjustable thresholds, as well as linear logical rules for identification of the R-peaks in real

  13. Simplified 2D Bidomain Model of Whole Heart Electrical Activity and ECG Generation

    Science.gov (United States)

    Sovilj, Siniša; Magjarević, Ratko; Abed, Amr Al; Lovell, Nigel H.; Dokos, Socrates

    2014-06-01

    The aim of this study was the development of a geometrically simple and highly computationally-efficient two dimensional (2D) biophysical model of whole heart electrical activity, incorporating spontaneous activation of the sinoatrial node (SAN), the specialized conduction system, and realistic surface ECG morphology computed on the torso. The FitzHugh-Nagumo (FHN) equations were incorporated into a bidomain finite element model of cardiac electrical activity, which was comprised of a simplified geometry of the whole heart with the blood cavities, the lungs and the torso as an extracellular volume conductor. To model the ECG, we placed four electrodes on the surface of the torso to simulate three Einthoven leads VI, VII and VIII from the standard 12-lead system. The 2D model was able to reconstruct ECG morphology on the torso from action potentials generated at various regions of the heart, including the sinoatrial node, atria, atrioventricular node, His bundle, bundle branches, Purkinje fibers, and ventricles. Our 2D cardiac model offers a good compromise between computational load and model complexity, and can be used as a first step towards three dimensional (3D) ECG models with more complex, precise and accurate geometry of anatomical structures, to investigate the effect of various cardiac electrophysiological parameters on ECG morphology.

  14. Wearable technology and ECG processing for fall risk assessment, prevention and detection.

    Science.gov (United States)

    Melillo, Paolo; Castaldo, Rossana; Sannino, Giovanna; Orrico, Ada; de Pietro, Giuseppe; Pecchia, Leandro

    2015-01-01

    Falls represent one of the most common causes of injury-related morbidity and mortality in later life. Subjects with cardiovascular disorders (e.g., related to autonomic dysfunctions and postural hypotension) are at higher risk of falling. Autonomic dysfunctions increasing the risk of falling in the short and mid-term could be assessed by Heart Rate Variability (HRV) extracted by electrocardiograph (ECG). We developed three trials for assessing the usefulness of ECG monitoring using wearable devices for: risk assessment of falling in the next few weeks; prevention of imminent falls due to standing hypotension; and fall detection. Statistical and data-mining methods are adopted to develop classification and regression models, validated with the cross-validation approach. The first classifier based on HRV features enabled to identify future fallers among hypertensive patients with an accuracy of 72% (sensitivity: 51.1%, specificity: 80.2%). The regression model to predict falls due to orthostatic dropdown from HRV recorded before standing achieved an overall accuracy of 80% (sensitivity: 92%, specificity: 90%). Finally, the classifier to detect simulated falls using ECG achieved an accuracy of 77.3% (sensitivity: 81.8%, specificity: 72.7%). The evidence from these three studies showed that ECG monitoring and processing could achieve satisfactory performances compared to other system for risk assessment, fall prevention and detection. This is interesting as differently from other technologies actually employed to prevent falls, ECG is recommended for many other pathologies of later life and is more accepted by senior citizens.

  15. Performance evaluation of wavelet-based ECG compression algorithms for telecardiology application over CDMA network.

    Science.gov (United States)

    Kim, Byung S; Yoo, Sun K

    2007-09-01

    The use of wireless networks bears great practical importance in instantaneous transmission of ECG signals during movement. In this paper, three typical wavelet-based ECG compression algorithms, Rajoub (RA), Embedded Zerotree Wavelet (EZ), and Wavelet Transform Higher-Order Statistics Coding (WH), were evaluated to find an appropriate ECG compression algorithm for scalable and reliable wireless tele-cardiology applications, particularly over a CDMA network. The short-term and long-term performance characteristics of the three algorithms were analyzed using normal, abnormal, and measurement noise-contaminated ECG signals from the MIT-BIH database. In addition to the processing delay measurement, compression efficiency and reconstruction sensitivity to error were also evaluated via simulation models including the noise-free channel model, random noise channel model, and CDMA channel model, as well as over an actual CDMA network currently operating in Korea. This study found that the EZ algorithm achieves the best compression efficiency within a low-noise environment, and that the WH algorithm is competitive for use in high-error environments with degraded short-term performance with abnormal or contaminated ECG signals.

  16. PROCESSING ECG SIGNAL WITH KAISER WINDOW- BASED FIR DIGITAL FILTERS BY

    Directory of Open Access Journals (Sweden)

    Mbachu C.B

    2011-08-01

    Full Text Available Heart attacks mostly occur in people who suffer from heart or heart-relate diseases if these diseases are not detected early enough and treated. There is therefore the need for a reliable means of detecting these diseases to save the patients from these attacks which are increasing in proportion all over the world. Electrocardiography (ECG, which is the electrical activity of the heart, generates a signal referred to as ECG signal or simply ECG and the shape of this signal tells much about the condition of the heart of a patient. Naturally the ECG signal gets distorted by different artifacts which must be removed otherwise it will convey an incorrect information regarding the patients heart condition. The work in this paper is the design of FIR digital filters with Kaiser Window to remove the interferences or the artifacts. Three filters are considered: low pass, high pass and notch filters. Each filter is used to filter the raw noisy ECG signal after which the three filters are used in cascade. Results are observed and recorded in each case, using FDA tool.

  17. Discrete wavelet transform and singular value decomposition based ECG steganography for secured patient information transmission.

    Science.gov (United States)

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

    2014-10-01

    ECG Steganography provides secured transmission of secret information such as patient personal information through ECG signals. This paper proposes an approach that uses discrete wavelet transform to decompose signals and singular value decomposition (SVD) to embed the secret information into the decomposed ECG signal. The novelty of the proposed method is to embed the watermark using SVD into the two dimensional (2D) ECG image. The embedding of secret information in a selected sub band of the decomposed ECG is achieved by replacing the singular values of the decomposed cover image by the singular values of the secret data. The performance assessment of the proposed approach allows understanding the suitable sub-band to hide secret data and the signal degradation that will affect diagnosability. Performance is measured using metrics like Kullback-Leibler divergence (KL), percentage residual difference (PRD), peak signal to noise ratio (PSNR) and bit error rate (BER). A dynamic location selection approach for embedding the singular values is also discussed. The proposed approach is demonstrated on a MIT-BIH database and the observations validate that HH is the ideal sub-band to hide data. It is also observed that the signal degradation (less than 0.6%) is very less in the proposed approach even with the secret data being as large as the sub band size. So, it does not affect the diagnosability and is reliable to transmit patient information.

  18. Support vector machines for automated recognition of obstructive sleep apnea syndrome from ECG recordings.

    Science.gov (United States)

    Khandoker, Ahsan H; Palaniswami, Marimuthu; Karmakar, Chandan K

    2009-01-01

    Obstructive sleep apnea syndrome (OSAS) is associated with cardiovascular morbidity as well as excessive daytime sleepiness and poor quality of life. In this study, we apply a machine learning technique [support vector machines (SVMs)] for automated recognition of OSAS types from their nocturnal ECG recordings. A total of 125 sets of nocturnal ECG recordings acquired from normal subjects (OSAS - ) and subjects with OSAS (OSAS +), each of approximately 8 h in duration, were analyzed. Features extracted from successive wavelet coefficient levels after wavelet decomposition of signals due to heart rate variability (HRV) from RR intervals and ECG-derived respiration (EDR) from R waves of QRS amplitudes were used as inputs to the SVMs to recognize OSAS +/- subjects. Using leave-one-out technique, the maximum accuracy of classification for 83 training sets was found to be 100% for SVMs using a subset of selected combination of HRV and EDR features. Independent test results on 42 subjects showed that it correctly recognized 24 out of 26 OSAS + subjects and 15 out of 16 OSAS - subjects (accuracy = 92.85%; Cohen's kappa value of 0.85). For estimating the relative severity of OSAS, the posterior probabilities of SVM outputs were calculated and compared with respective apnea/hypopnea index. These results suggest superior performance of SVMs in OSAS recognition supported by wavelet-based features of ECG. The results demonstrate considerable potential in applying SVMs in an ECG-based screening device that can aid a sleep specialist in the initial assessment of patients with suspected OSAS.

  19. 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.

  20. Removal of Baseline Wander Noise from Electrocardiogram (ECG using Fifth-order Spline Interpolation

    Directory of Open Access Journals (Sweden)

    John A. OJO

    2016-10-01

    Full Text Available Baseline wandering can mask some important features of the Electrocardiogram (ECG signal hence it is desirable to remove this noise for proper analysis and display of the ECG signal. This paper presents the implementation and evaluation of spline interpolation and linear phase FIR filtering methods to remove this noise. Spline interpolation method requires the QRS waves to be first detected and fifth-order (quintic interpolation technique applied to determine the smoothest curve joining several QRS points. Filtering of the ECG baseline wander was performed by using the difference between the estimated baseline wander and the noisy ECG signal. ECG signals from the MIT-BIT arrhythmia database was used to test the system, while the technique was implemented in MATLAB. The performance of the system was evaluated using Average Power (AP after filtering, Mean Square Error (MSE and the Signal to Noise Ratio (SNR. The quintic spline interpolation gave the best performance in terms of AP, MSE and SNR when compared with linear phase filtering and cubic (3rd-order spline interpolation methods.

  1. ECG pattern in reverse takotsubo cardiomyopathy demonstrated in 5 cases with intracranial hemorrhage.

    Science.gov (United States)

    Elikowski, Waldemar; Małek-Elikowska, Małgorzata; Kudliński, Bartosz; Skrzywanek, Paweł; Smól, Sławomir; Rzymski, Stanisław

    2016-09-29

    In typical takotsubo cardiomyopathy (TC) apical transient left ventricular dysfunction with concomitant ECG changes mimicking acute anterior myocardial infarction can be observed. Reverse TC (RTC) characterized by contractile disturbances in all basal and often simultaneous mid-ventricular segments is definitely less frequent. ECG pattern of RTC is less known. The authors present ECG findings in 5 cases of RTC in course of intracranial hemorrhage (ICH); 3 patients were diagnosed with subarachnoid hemorrhage (SAH) and the other two with intracerebral hemorrhage or subdural posttraumatic hematoma. In all patients, initial ECG appearance was dominated by ST segment depression in inferior leads (II, III, avF) and/or lateral leads (V4-6). In 4 patients, concurrent ST segment elevation in avR and avL leads was seen, additionally 4 patients had low QRS voltage in high lateral leads (I, avL). Potential normalization of these changes did not influence the patient`s survival. In one woman, immediately before death, early repolarization was recorded. In subjects with an increased risk of TC, for example in intracranial hemorrhage, particularly in SAH, the ECG abnormalities presented may indicate a need for further search of its atypical echocardiographic variants.

  2. Development and feasibility of a smartphone, ECG and GPS based system for remotely monitoring exercise in cardiac rehabilitation.

    Directory of Open Access Journals (Sweden)

    Charles Worringham

    Full Text Available BACKGROUND: Despite its efficacy and cost-effectiveness, exercise-based cardiac rehabilitation is undertaken by less than one-third of clinically eligible cardiac patients in every country for which data is available. Reasons for non-participation include the unavailability of hospital-based rehabilitation programs, or excessive travel time and distance. For this reason, there have been calls for the development of more flexible alternatives. METHODOLOGY AND PRINCIPAL FINDINGS: We developed a system to enable walking-based cardiac rehabilitation in which the patient's single-lead ECG, heart rate, GPS-based speed and location are transmitted by a programmed smartphone to a secure server for real-time monitoring by a qualified exercise scientist. The feasibility of this approach was evaluated in 134 remotely-monitored exercise assessment and exercise sessions in cardiac patients unable to undertake hospital-based rehabilitation. Completion rates, rates of technical problems, detection of ECG changes, pre- and post-intervention six minute walk test (6 MWT, cardiac depression and Quality of Life (QOL were key measures. The system was rated as easy and quick to use. It allowed participants to complete six weeks of exercise-based rehabilitation near their homes, worksites, or when travelling. The majority of sessions were completed without any technical problems, although periodic signal loss in areas of poor coverage was an occasional limitation. Several exercise and post-exercise ECG changes were detected. Participants showed improvements comparable to those reported for hospital-based programs, walking significantly further on the post-intervention 6 MWT, 637 m (95% CI: 565-726, than on the pre-test, 524 m (95% CI: 420-655, and reporting significantly reduced levels of cardiac depression and significantly improved physical health-related QOL. CONCLUSIONS AND SIGNIFICANCE: The system provided a feasible and very flexible alternative form of

  3. FPGA compression of ECG signals by using modified convolution scheme of the Discrete Wavelet Transform Compresión de señales ECG sobre FPGA utilizando un esquema modificado de convolución de la Transformada Wavelet Discreta

    Directory of Open Access Journals (Sweden)

    Dora M Ballesteros

    2012-04-01

    Full Text Available This paper presents FPGA design of ECG compression by using the Discrete Wavelet Transform (DWT and one lossless encoding method. Unlike the classical works based on off-line mode, the current work allows the real-time processing of the ECG signal to reduce the redundant information. A model is developed for a fixed-point convolution scheme which has a good performance in relation to the throughput, the latency, the maximum frequency of operation and the quality of the compressed signal. The quantization of the coefficients of the filters and the selected fixed-threshold give a low error in relation to clinical applications.Este documento presenta el diseño basado en FPGA para la compresión de señales ECG utilizando la Transformada Wavelet Discreta y un método de codificación sin pérdida de información. A diferencia de los trabajos clásicos para modo off-line, el trabajo actual permite la compresión en tiempo real de la señal ECG por medio de la reducción de la información redundante. Se propone un modelo para el esquema de convolución en formato punto fijo, el cual tiene buen desempeño en relación a la tasa de salida, la latencia del sistema, la máxima frecuencia de operación y la calidad de la señal comprimida. La arquitectura propuesta, la cuantización utilizada y el método de codificación proporcionan un PRD que es apto para el análisis clínico.

  4. Geology of the Aspen 15-minute quadrangle, Pitkin and Gunnison counties, Colorado

    Science.gov (United States)

    Bryant, Bruce

    1979-01-01

    The Aspen area, located 170 km southwest of Denver, Colo., lies at the intersection of the northeast-trending Colorado mineral belt and the west margin of the north-trending Sawatch uplift of Laramide age; it is within the southwest part of the northwest-trending late Paleozoic Eagle basin. Precambrian shales and graywackes, perhaps as old as 2 billion years (b.y.), were converted to sillimanite-bearing gneiss and muscovite-biotite schist 1.65-1.70 b.y. ago. They were deformed into northeast-plunging folds and were migmatized, and they were intruded by quartz diorite, porphyritic quartz monzonite, and granite. Muscovite-biotite quartz monzonite intruded this older Precambrian terrane about 1.45 b.y. ago and is the predominant Precambrian rock near Aspen. Uplift, some faulting, and much erosion occurred during the 900-million year (m.y.) interval between emplacement of the plutonic rocks and deposition of Upper Cambrian sediments. From Late Cambrian through Mississippian the region was part of a broad area alternately covered by shallow seas or occupied by low-lying land. Quartzite, dolomite, and limestone 200-320 m thick, comprising the Sawatch Quartzite and Peerless Formation (Cambrian), Manitou Dolomite (Ordovician), Chaffee Group (Mississippian(?) and Devonian), and Leadville Limestone (Mississippian) were deposited during this interval. After an hiatus during which soil formation and solution of the Leadville Limestone took place in the Late Mississippian, a thick sequence of marine and nonmarine clastic rocks was deposited in the newly developing Eagle basin during the late Paleozoic and early Mesozoic. Deposition of about 300 m of carbonaceous shale, limestone, dolomite, and minor siltstone and evaporite of the Belden Formation began in a shallow sea in Early and Middle Pennsylvanian time. Facies relations indicate that the northwest-trending Uncompahgre uplift southwest of Aspen, if present at that time, had very low relief. The overlying Middle Pennsylvanian Gothic Formation of Langenheim (1952) contains calcareous sandstone, siltstone, shale, limestone, and evaporite. Its clastic debris, significantly coarser than that in the Belden, signals the initial rise of the Uncompahgre uplift bordering the Eagle basin on the southwest; the Gothic here lacks the conglomerates and fossiliferous marine limestones found closer to the uplift. Red terrigenous clastic rocks and minor limestone and evaporite of the Maroon Formation as much as 3,200 m thick, deposited mainly in a fluvial flood-plain environment during the rest of the Pennsylvanian and the Early Permian, indicate withdrawal of the sea caused by further uplift of the Uncompahgre highland. Following an hiatus accompanied by local folding, the red conglomerate, sandstone, and siltstone of the State Bridge Formation (Late Permian and Early Triassic) was deposited in a fluvial-lacustrine environment adjacent to a much-expanded Uncompahgre uplift; a significant part of the State Bridge is material recycled from the Maroon Formation exposed to erosion on the flank of the uplift. The State Bridge, absent towards the south, becomes thicker and finer grained towards the north. The Chinle Formation (Late Triassic) rests with angular unconformity on the State Bridge Formation. The Chinle contains a basal discontinuous quartz-pebble conglomerate (Gartra Member) and is chiefly calcareous siltstone and limestone, with some beds of sandstone and conglomerate composed of fragments derived from the limestone beds. The Chinle was deposited on flood plains and in lakes by streams. Storms may have disrupted the sediments in the lakes producing the limestone pebble conglomerates. The lack of feldspar in the Chinle indicates that the nearby part of the Uncompahgre uplift was not a sediment source, or was covered by a deeply weathered feldspar-free mantle. The formation, absent towards the south, thickens toward the north. Thicknesses of the Maroon, State Bridge, and Ch

  5. The usefulness of the consensus clinical diagnostic criteria in Brugada syndrome

    NARCIS (Netherlands)

    Sarkozy, A.; Paparella, G.; Boussy, T.; Casado-Arroyo, R.; Yazaki, Y.; Chierchia, G.B.; Asmundis, C. de; Bayrak, F.; Namdar, M.; Richter, S.; Brugada, J.; Brugada, P.

    2013-01-01

    BACKGROUND: Consensus statements were proposed for the diagnosis of Brugada syndrome (BS). The clinical diagnostic criteria were defined as documented ventricular fibrillation or ventricular tachycardia (VT), family history of sudden cardiac death at <45 years, diagnostic ECGs of family members,

  6. Prolonged corrected QT interval is predictive of future stroke events even in subjects without ECG-diagnosed left ventricular hypertrophy.

    Science.gov (United States)

    Ishikawa, Joji; Ishikawa, Shizukiyo; Kario, Kazuomi

    2015-03-01

    We attempted to evaluate whether subjects who exhibit prolonged corrected QT (QTc) interval (≥440 ms in men and ≥460 ms in women) on ECG, with and without ECG-diagnosed left ventricular hypertrophy (ECG-LVH; Cornell product, ≥244 mV×ms), are at increased risk of stroke. Among the 10 643 subjects, there were a total of 375 stroke events during the follow-up period (128.7±28.1 months; 114 142 person-years). The subjects with prolonged QTc interval (hazard ratio, 2.13; 95% confidence interval, 1.22-3.73) had an increased risk of stroke even after adjustment for ECG-LVH (hazard ratio, 1.71; 95% confidence interval, 1.22-2.40). When we stratified the subjects into those with neither a prolonged QTc interval nor ECG-LVH, those with a prolonged QTc interval but without ECG-LVH, and those with ECG-LVH, multivariate-adjusted Cox proportional hazards analysis demonstrated that the subjects with prolonged QTc intervals but not ECG-LVH (1.2% of all subjects; incidence, 10.7%; hazard ratio, 2.70, 95% confidence interval, 1.48-4.94) and those with ECG-LVH (incidence, 7.9%; hazard ratio, 1.83; 95% confidence interval, 1.31-2.57) had an increased risk of stroke events, compared with those with neither a prolonged QTc interval nor ECG-LVH. In conclusion, prolonged QTc interval was associated with stroke risk even among patients without ECG-LVH in the general population.

  7. A PC-based generator of surface ECG potentials for computer electrocardiograph testing.

    Science.gov (United States)

    Franchi, D; Palagi, G; Bedini, R

    1994-02-01

    The system is composed of an electronic circuit, connected to a PC, whose outputs, starting from ECGs digitally collected by commercial interpretative electrocardiographs, simulate virtual patients' limb and chest electrode potentials. Appropriate software manages the D/A conversion and lines up the original short-term signal in a ring buffer to generate continuous ECG traces. The device also permits the addition of artifacts and/or baseline wanders/shifts on each lead separately. The system has been accurately tested and statistical indexes have been computed to quantify the reproduction accuracy analyzing, in the generated signal, both the errors induced on the fiducial point measurements and the capability to retain the diagnostic significance. The device integrated with an annotated ECG data base constitutes a reliable and powerful system to be used in the quality assurance testing of computer electrocardiographs.

  8. Using an injection signal to reduce motion artifacts in capacitive ECG measurements.

    Science.gov (United States)

    Serteyn, Aline; Vullings, Rik; Meftah, Mohammed; Bergmans, Jan

    2013-01-01

    Capacitive electrodes are a promising alternative to the conventional adhesive ECG electrodes. They provide more comfort to the patient when integrated in everyday objects (e.g. beds or seats) for long-term monitoring. However, the application of such electrodes is limited by their high sensitivity to motion artifacts. Artifacts caused by variation of the coupling capacitance are studied here. An injection signal is proposed to track these variations in real-time. An adaptive filter then estimates the motion artifact and cancels it from the recorded ECG. The amplitude of the motion artifact is reduced in average by 29 dB in simulation and by 20 dB in a lab environment. Our method has the advantages that it is able to reduce motion artifacts occurring in the frequency band of the ECG and that it does not require knowledge about the measurement system.

  9. Wavelet-based watermarking and compression for ECG signals with verification evaluation.

    Science.gov (United States)

    Tseng, Kuo-Kun; He, Xialong; Kung, Woon-Man; Chen, Shuo-Tsung; Liao, Minghong; Huang, Huang-Nan

    2014-01-01

    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.

  10. Labview Based ECG Patient Monitoring System for Cardiovascular Patient Using SMTP Technology.

    Science.gov (United States)

    Singh, Om Prakash; Mekonnen, Dawit; Malarvili, M B

    2015-01-01

    This paper leads to developing a Labview based ECG patient monitoring system for cardiovascular patient using Simple Mail Transfer Protocol technology. The designed device has been divided into three parts. First part is ECG amplifier circuit, built using instrumentation amplifier (AD620) followed by signal conditioning circuit with the operation amplifier (lm741). Secondly, the DAQ card is used to convert the analog signal into digital form for the further process. Furthermore, the data has been processed in Labview where the digital filter techniques have been implemented to remove the noise from the acquired signal. After processing, the algorithm was developed to calculate the heart rate and to analyze the arrhythmia condition. Finally, SMTP technology has been added in our work to make device more communicative and much more cost-effective solution in telemedicine technology which has been key-problem to realize the telediagnosis and monitoring of ECG signals. The technology also can be easily implemented over already existing Internet.

  11. Independent component analysis and decision trees for ECG holter recording de-noising.

    Directory of Open Access Journals (Sweden)

    Jakub Kuzilek

    Full Text Available We have developed a method focusing on ECG signal de-noising using Independent component analysis (ICA. This approach combines JADE source separation and binary decision tree for identification and subsequent ECG noise removal. In order to to test the efficiency of this method comparison to standard filtering a wavelet- based de-noising method was used. Freely data available at Physionet medical data storage were evaluated. Evaluation criteria was root mean square error (RMSE between original ECG and filtered data contaminated with artificial noise. Proposed algorithm achieved comparable result in terms of standard noises (power line interference, base line wander, EMG, but noticeably significantly better results were achieved when uncommon noise (electrode cable movement artefact were compared.

  12. A novel ECG telemetry and monitoring system based on Z-Wave communication.

    Science.gov (United States)

    Csernath, Geza; Szilagyi, Laszlo; Fordos, Gergely; Szilagyi, Sandor M

    2008-01-01

    This paper presents a novel ECG telemetry system based on Z-Wave communication protocol. The proposed system consists of small portable devices that acquire, compress and transmit the ECG to a RF-USB interface connected to a central monitoring computer. The received signals are filtered, QRS complexes and P and T waves are localized, and different waveforms are classified in order to be able to provide diagnosis tools like heart rate variability and turbulence analysis. Due to the limitation of communication bandwidth, the maximum number of measuring devices connected to a central monitor is four. The proposed system composed of inexpensive components can serve as flexible alternative to current ECG monitoring systems.

  13. An ultra low power ECG signal processor design for cardiovascular disease detection.

    Science.gov (United States)

    Jain, Sanjeev Kumar; Bhaumik, Basabi

    2015-08-01

    This paper presents an ultra low power ASIC design based on a new cardiovascular disease diagnostic algorithm. This new algorithm based on forward search is designed for real time ECG signal processing. The algorithm is evaluated for Physionet PTB database from the point of view of cardiovascular disease diagnosis. The failed detection rate of QRS complex peak detection of our algorithm ranges from 0.07% to 0.26% for multi lead ECG signal. The ASIC is designed using 130-nm CMOS low leakage process technology. The area of ASIC is 1.21 mm(2). This ASIC consumes only 96 nW at an operating frequency of 1 kHz with a supply voltage of 0.9 V. Due to ultra low power consumption, our proposed ASIC design is most suitable for energy efficient wearable ECG monitoring devices.

  14. 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.

  15. Reliable resource-constrained telecardiology via compressive detection of anomalous ECG signals.

    Science.gov (United States)

    Chandra, Bollepalli S; Sastry, Challa S; Jana, Soumya

    2015-11-01

    Telecardiology is envisaged as a supplement to inadequate local cardiac care, especially, in infrastructure deficient communities. Yet the associated infrastructure constraints are often ignored while designing a traditional telecardiology system that simply records and transmits user electrocardiogram (ECG) signals to a professional diagnostic facility. Against this backdrop, we propose a two-tier telecardiology framework, where constraints on resources, such as power and bandwidth, are met by compressively sampling ECG signals, identifying anomalous signals, and transmitting only the anomalous signals. Specifically, we design practical compressive classifiers based on inherent properties of ECG signals, such as self-similarity and periodicity, and illustrate their efficacy by plotting receiver operating characteristics (ROC). Using such classifiers, we realize a resource-constrained telecardiology system, which, for the PhysioNet databases, allows no more than 0.5% undetected patients even at an average downsampling factor of five, reducing the power requirement by 80% and bandwidth requirement by 83.4% compared to traditional telecardiology.

  16. DETECTION OF QRS COMPLEXES OF ECG RECORDING BASED ON WAVELET TRANSFORM USING MATLAB

    Directory of Open Access Journals (Sweden)

    Ruchita Gautam,

    2010-07-01

    Full Text Available The electrocardiogram (ECG is quite important tool to find out more information about the heart. The main tasks in ECG signal analysis are the detection of QRS complex (i.e. R wave, and the estimation ofinstantaneous heart rate by measuring the time interval between two consecutive R-waves. After recognizing R wave, other components like P, Q, S and T can be detected by using window method. In this paper, we describe a QRS complex detector based on the Dyadic wavelet transform (DyWT which is robust in comparison with time- varying QRS complex morphology and to noise. We illustrate the performance of the DyWT-based QRS detector by considering problematic ECG signals from Common Standard for Electrocardiography (CSE database. We also compare and analyze its performance to some of the QRS detectors developed in the past.

  17. A COMPRESSION ALGORITHM FOR ECG BASED ON INTEGER LIFTING SCHEME WAVELET TRANSFORM

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In view of the shortcomes of conventional ElectroCardioGram (ECG) compression algorithms, such as high complexity of operation and distortion of reconstructed signal, a new ECG compression encoding algorithm based on Set Partitioning In Hierarchical Trees (SPIHT) is brought out after studying the integer lifting scheme wavelet transform in detail. The proposed algorithm modifies zero-tree structure of SPIHT, establishes single dimensional wavelet coefficient tree of ECG signals and enhances the efficiency of SPIHT-encoding by distributing bits rationally, improving zero-tree set and ameliorating classifying method. For this improved algorithm, floating-point computation and storage are left out of consideration and it is easy to be implemented by hardware and software. Experimental results prove that the new algorithm has admirable features of low complexity,high speed and good performance in signal reconstruction. High compression ratio is obtained with high signal fidelity as well.

  18. ECG processing techniques based on neural networks and bidirectional associative memories.

    Science.gov (United States)

    Maglaveras, N; Stamkopoulos, T; Pappas, C; Strintzis, M

    1998-01-01

    Two ECG processing techniques are described for the classification of QRSs, PVCs and normal and ischaemic beats. The techniques use neural network (NN) technology in two ways. The first technique, uses nonlinear ECG mapping preprocessing and subsequently for classification uses a shrinking algorithm based on NNs. This technique is applied to the QRS/PVC problem with good result. The second technique is based on the Bidirectional Associative Memory (BAM) NN and is used to distinguish normal from ischaemic beats. In this technique the ECG beat is treated as a digitized image which is then transformed into a bipolar vector suitable for input in the BAM. The results show that this method, if properly calibrated, can result in a fast and reliable ischaemic beat detection algorithm.

  19. ECG and enzymatic indicators of therapeutic success after intravenous streptokinase for acute myocardial infarction

    DEFF Research Database (Denmark)

    Clemmensen, P; Grande, P; Pedersen, F

    1990-01-01

    Thrombolytic therapy has been documented to result in reperfusion of jeopardized myocardium and reduction in the size of the acute myocardial infarction (AMI). The effect of intravenous streptokinase on a creatine kinase-MB (CK-MB) reperfusion index and an ECG estimate of myocardial salvage...... was therefore studied in 65 patients with a first AMI, randomized to treatment with streptokinase (n = 33) or placebo (control group, n = 32). Reperfusion was defined as a CK-MB appearance rate constant (k1) greater than 0.185. The final AMI size was first predicted from the admission standard ECG by previously...... developed formulas based on ST segment elevation. The final AMI size was estimated from the QRS score on the predischarge ECG. Myocardial salvage was defined as a greater than or equal to 20% decrease from predicted to final AMI size. The k1 value in the control group was significantly lower than...

  20. Community-Based ECG Monitoring System for Patients with Cardiovascular Diseases.

    Science.gov (United States)

    Lin, Bor-Shyh; Wong, Alice M; Tseng, Kevin C

    2016-04-01

    This study aims to develop a community-based electrocardiogram (ECG) monitoring system for cardiac outpatients to wirelessly detect heart rate, provide personalized healthcare, and enhance interactive social contact because of the prevalence of deaths from cardiovascular disease and the growing problem of aging in the world. The system not only strengthens the performance of the ECG monitoring system but also emphasizes the ergonomic design of wearable devices and user interfaces. In addition, it enables medical professionals to diagnose cardiac symptoms remotely and electronically manage medical reports and suggestions. The experimental result shows high performance of the dry electrode, even in dynamic conditions. The comparison result with different ECG healthcare systems shows the essential factors that the system should possess and the capability of the proposed system. Finally, a user survey was conducted based on the unified theory of acceptance and users of technology (UTAUT) model.

  1. A Novel Technique for Fetal ECG Extraction Using Single-Channel Abdominal Recording

    Directory of Open Access Journals (Sweden)

    Nannan Zhang

    2017-02-01

    Full Text Available Non-invasive fetal electrocardiograms (FECGs are an alternative method to standard means of fetal monitoring which permit long-term continual monitoring. However, in abdominal recording, the FECG amplitude is weak in the temporal domain and overlaps with the maternal electrocardiogram (MECG in the spectral domain. Research in the area of non-invasive separations of FECG from abdominal electrocardiograms (AECGs is in its infancy and several studies are currently focusing on this area. An adaptive noise canceller (ANC is commonly used for cancelling interference in cases where the reference signal only correlates with an interference signal, and not with a signal of interest. However, results from some existing studies suggest that propagation of electrocardiogram (ECG signals from the maternal heart to the abdomen is nonlinear, hence the adaptive filter approach may fail if the thoracic and abdominal MECG lack strict waveform similarity. In this study, singular value decomposition (SVD and smooth window (SW techniques are combined to build a reference signal in an ANC. This is to avoid the limitation that thoracic MECGs recorded separately must be similar to abdominal MECGs in waveform. Validation of the proposed method with r01 and r07 signals from a public dataset, and a self-recorded private dataset showed that the proposed method achieved F1 scores of 99.61%, 99.28% and 98.58%, respectively for the detection of fetal QRS. Compared with four other single-channel methods, the proposed method also achieved higher accuracy values of 99.22%, 98.57% and 97.21%, respectively. The findings from this study suggest that the proposed method could potentially aid accurate extraction of FECG from MECG recordings in both clinical and commercial applications.

  2. A Novel Technique for Fetal ECG Extraction Using Single-Channel Abdominal Recording

    Science.gov (United States)

    Zhang, Nannan; Zhang, Jinyong; Li, Hui; Mumini, Omisore Olatunji; Samuel, Oluwarotimi Williams; Ivanov, Kamen; Wang, Lei

    2017-01-01

    Non-invasive fetal electrocardiograms (FECGs) are an alternative method to standard means of fetal monitoring which permit long-term continual monitoring. However, in abdominal recording, the FECG amplitude is weak in the temporal domain and overlaps with the maternal electrocardiogram (MECG) in the spectral domain. Research in the area of non-invasive separations of FECG from abdominal electrocardiograms (AECGs) is in its infancy and several studies are currently focusing on this area. An adaptive noise canceller (ANC) is commonly used for cancelling interference in cases where the reference signal only correlates with an interference signal, and not with a signal of interest. However, results from some existing studies suggest that propagation of electrocardiogram (ECG) signals from the maternal heart to the abdomen is nonlinear, hence the adaptive filter approach may fail if the thoracic and abdominal MECG lack strict waveform similarity. In this study, singular value decomposition (SVD) and smooth window (SW) techniques are combined to build a reference signal in an ANC. This is to avoid the limitation that thoracic MECGs recorded separately must be similar to abdominal MECGs in waveform. Validation of the proposed method with r01 and r07 signals from a public dataset, and a self-recorded private dataset showed that the proposed method achieved F1 scores of 99.61%, 99.28% and 98.58%, respectively for the detection of fetal QRS. Compared with four other single-channel methods, the proposed method also achieved higher accuracy values of 99.22%, 98.57% and 97.21%, respectively. The findings from this study suggest that the proposed method could potentially aid accurate extraction of FECG from MECG recordings in both clinical and commercial applications. PMID:28245585

  3. Achieving consistent image quality with dose optimization in 64-row multidetector computed tomography prospective ECG gated coronary calcium scoring.

    Science.gov (United States)

    Pan, Zilai; Pang, Lifang; Li, Jianying; Zhang, Huan; Yang, Wenjie; Ding, Bei; Chai, Weimin; Chen, Kemin; Yao, Weiwu

    2011-04-01

    To evaluate the clinical value of a body mass index (BMI) based tube current (mA) selection method for obtaining consistent image quality with dose optimization in MDCT prospective ECG gated coronary calcium scoring. A formula for selecting mA to achieve desired image quality based on patient BMI was established using a control group (A) of 200 MDCT cardiac patients with a standard scan protocol. One hundred patients in Group B were scanned with this BMI-dependent mA for achieving a desired noise level of 18 HU at 2.5 mm slice thickness. The CTDIvol and image noise on the ascending aorta for the two groups were recorded. Two experienced radiologists quantitatively evaluated the image quality using scores of 1-4 with 4 being the highest. The image quality scores had no statistical difference (P = 0.71) at 3.89 ± 0.32, 3.87 ± 0.34, respectively, for groups A and B of similar BMI. The image noise in Group A had linear relationship with BMI. The image noise in Group B using BMI-dependent mA was independent of BMI with average value of 17.9 HU and smaller deviations for the noise values than in Group A (2.0 vs. 2.9 HU). There was a 35% dose reduction with BMI-dependent mA selection method on average with the lowest effective dose being only 0.35 mSv for patient with BMI of 18.3. A quantitative BMI-based mA selection method in MDCT prospective ECG gated coronary calcium scoring has been proposed to obtain a desired and consistent image quality and provide dose optimization across patient population.

  4. Semisupervised ECG Ventricular Beat Classification With Novelty Detection Based on Switching Kalman Filters.

    Science.gov (United States)

    Oster, Julien; Behar, Joachim; Sayadi, Omid; Nemati, Shamim; Johnson, Alistair E W; Clifford, Gari D

    2015-09-01

    Automatic processing and accurate diagnosis of pathological electrocardiogram (ECG) signals remains a challenge. As long-term ECG recordings continue to increase in prevalence, driven partly by the ease of remote monitoring technology usage, the need to automate ECG analysis continues to grow. In previous studies, a model-based ECG filtering approach to ECG data from healthy subjects has been applied to facilitate accurate online filtering and analysis of physiological signals. We propose an extension of this approach, which models not only normal and ventricular heartbeats, but also morphologies not previously encountered. A switching Kalman filter approach is introduced to enable the automatic selection of the most likely mode (beat type), while simultaneously filtering the signal using appropriate prior knowledge. Novelty detection is also made possible by incorporating a third mode for the detection of unknown (not previously observed) morphologies, and denoted as X-factor. This new approach is compared to state-of-the-art techniques for the ventricular heartbeat classification in the MIT-BIH arrhythmia and Incart databases. F1 scores of 98.3% and 99.5% were found on each database, respectively, which are superior to other published algorithms' results reported on the same databases. Only 3% of all the beats were discarded as X-factor, and the majority of these beats contained high levels of noise. The proposed technique demonstrates accurate beat classification in the presence of previously unseen (and unlearned) morphologies and noise, and provides an automated method for morphological analysis of arbitrary (unknown) ECG leads.

  5. Study on diagnosis to remote ECG monitoring for arrhythmia%远程心电监测对心律失常的诊断研究

    Institute of Scientific and Technical Information of China (English)

    韩伟华; 姚锦容; 林永霞; 黎文婷

    2012-01-01

    Objective To investigate the application value of remote ECG monitoring for arrhythmia diagnosis.Methods From April 2010 to December 2011, 80 cases of arrhythmia patients treated in our hospital were.chosen,at first,each patient had a 24-hour Holter monitoring.After the end of Holter monitoring,80 patients had the remote ECG monitoring, then we analyzed the ECG data of the two monitoring methods.Arthythmia detection rates of the two methods were calculated.The arrhythmia detection rates were compared and the types of arrhythmia were analyzed.Results The arrhythmia detection rate of 24-hour ambulatory ECG was 52.5%,3 cases were detected irregular arrhythmia; the detection rate of remote ECG monitoring was 86.3%,2 cases detected irregular arrhythmia(P < 0.05).Conclusion Remote ECG monitoring can not only bring convenience to the arrhythmia diagnosis,but also has a higher detection rate,a certain detection to irregular heart rate.It is a strong complement of hospital routine heart rate diagram check and 24-hour Holter.So remote ECG monitoring has a great significance in the clinical diagnosis of abnormal heart rhythms.%目的 探讨远程心电监测对心律失常诊断的应用价值.方法 选取2010年4月-2011年12月来我院就诊的80例心律失常患者,每位患者先进行24小时动态心电图监测,动态心电图监测结束后再进行远程心电监测.分析两种监测方法所得的心电数据,计算心律失常检出率,比较心律失常检出率并对两种方法检测出的心律失常患者进一步行心律失常类型分析.结果 24小时动态心电图中,心律失常检出率为52.5%,不规则心律失常患者检出3例;远程心电监测的心律失常检出率为86.3%,不规则心律失常患者检出2例(P<0.05).结论 远程心电监测不仅可以实行远程心电记录给心律失常诊断带来便利,检出率较高,而且对不规则心律失常也有一定检出率,是院内常规心电图检查和24小时动态

  6. 住院精神病人伴发低钾血症105例心电图分析%Hospitalized psychiatric patients associated with 105 cases of hypokalemia ECG analysis

    Institute of Scientific and Technical Information of China (English)

    余利英

    2014-01-01

    Objective:To investigate the characteristics of hypokalemia ECG changes and serum potassium concentration. Methods:105 cases of patients with ECG characteristics and serum potassium concentration for comparative analysis. Results:showed hypokalemia ECG U wave obviously, TU fusion, QT or QU prolongation,ST segment depression,T wave changes and cardiac arrhythmias;electrocardiogram and serum potassium concentration are in good agreement,ECG abnormalities the incidence and severity of disease potassium.Conclusions:Clinical hypokalemia various ECG abnormalities, contribute to the timely discovery hypokalemia and therapy.%目的:探讨低钾血症心电图变化特征及与血清钾浓度的关系。方法:将105例患者的心电图特征及血清钾浓度作对比分析。结果:低钾血症的心电图表现为U波明显、T-U融合、Q-T或Q-U间期延长、ST段下移、T波改变和心律失常;心电图与血清钾浓度有较好的一致性,心电图异常表现的发生率与低钾症的严重程度有关。结论:临床上低钾血症心电图的各种异常表现,有助于及时发现低钾血症和指导治疗。

  7. Application study of ECG scatter plot in the analysis of heart rate variability%心电散点图在心率变异性分析中的应用研究

    Institute of Scientific and Technical Information of China (English)

    杨桦

    2016-01-01

    目的:分析心电散点图在心率变异性分析中的应用价值。方法:将122例动态心电图数据心率变异性分析心电散点图和时域、频域治疗进行对应分析,明确心电散点图指标的特征。结果:心电散点图表达心率变异分析各项指标和时域、频率等指标存在着对应的联系,心电散点图能够直接观察到图像变化的情况,清晰地了解窦性心搏图形与干扰伪差图形之间的区别,窦性心搏图形呈现出针对性与多样性的特点。结论:心电散点图在心率变异性分析中的应用价值较为突出,能够有效辨识出心率变异性分析中的时域、频域等,临床检验正确率较高。%Objective:To analyze the application value of ECG scatter plot in the analysis of heart rate variability.Methods:122 cases of dynamic ECG data heart rate variability analysis of ECG scatter plot and time domain.Frequency domain treatment were given corresponding analysis.The characteristics of ECG scatter point were cleared.Results:The ECG scatter plot expresses that there was a corresponding relationship between the indexes of heart rate variability analysis and time domain and frequency.ECG scatter plot can directly observe the changes situation of the image,clear understand the distinction between sinus cardiac graphics and pseudo differential interference graphics.The sinus cardiac graphics showed the characteristics of pertinence and diversity.Conclusion:The application value of ECG scatter plot in the analysis of heart rate variability is more prominent,which can effectively identify the time domain and frequency domain of heart rate variability analysis.The correct rate of clinical examination is higher.

  8. ECG Denoising Using Marginalized Particle Extended Kalman Filter with an Automatic Particle Weighting Strategy.

    Science.gov (United States)

    Hesar, Hamed; Mohebbi, Maryam

    2016-06-20

    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 non-stationary situations (such as presence of pink noise, brown noise, and real muscle artifacts). 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

  9. Simulation methods for the online extraction of ECG parameters under Matlab/Simulink.

    Science.gov (United States)

    von Wagner, G; Kunzmann, U; Schöchlin, J; Bolz, A

    2002-01-01

    The classification of cardiac pathologies in the human ECG greatly depends on the reliable extraction of characteristic features. This work presents a complete simulation environment for testing ECG classification algorithms under Matlab/Simulink. Evaluation of algorithm performance is undertaken in full compliance with the ANSI/AAMI standards EC38 and EC57, and ranges from beat-to-beat analysis to the comparison of episode markers (e.g., for VT/VF detection algorithms). For testing the quality of waveform boundary detection, our own testing methods have been implemented in compliance with existing literature.

  10. A Low Power Front End Analog Multiplexing Unit for 12 Lead ECG Signal Acquisition

    Directory of Open Access Journals (Sweden)

    D.Hari Priya

    2014-10-01

    Full Text Available The design of CMOS analog circuitry for acquiring 12 lead ECG is presented. The existing methods employ separate multiplexers and associated circuitry for signal acquisition operating at typical voltage of ± 5V. The proposed system employs dynamic threshold logic to achieve low power, wide dynamic range good linearity with a supply voltage of 0.4V. The power dissipation obtained was 22.12µW. Utilizing the dynamic threshold logic the proposed circuitry is implemented with 0.18µm CMOS technology. This ECG signal processor is highly suitable for wearable applications of long term cardiac monitoring.

  11. A Low Power Front End Analog Multiplexing Unit for 12 Lead ECG Signal Acquisition

    Directory of Open Access Journals (Sweden)

    D.Hari Priya

    2014-04-01

    Full Text Available The design of CMOS analog circuitry for acquiring 12 lead ECG is presented. The existing methods employ separate multiplexers and associated circuitry for signal acquisition operating at typical voltage of ± 5V. The proposed system employs dynamic threshold logic to achieve low power, wide dynamic range good linearity with a supply voltage of 0.4V. The power dissipation obtained was 22.12µW. Utilizing the dynamic threshold logic the proposed circuitry is implemented with 0.18µm CMOS technology. This ECG signal processor is highly suitable for wearable applications of long term cardiac monitoring.

  12. Skin-electrode impedance measurement during ECG acquisition: method’s validation

    Science.gov (United States)

    Casal, Leonardo; La Mura, Guillermo

    2016-04-01

    Skm-electrode impedance measurement can provide valuable information prior. dunng and post electrocardiographic (ECG) or electroencephalographs (EEG) acquisitions. In this work we validate a method for skm-electrode impedance measurement using test circuits with known resistance and capacitor values, at different frequencies for injected excitation current. Finally the method is successfully used for impedance measurement during ECG acquisition on a subject usmg 125 Hz and 6 nA square wave excitation signal at instrumentation amplifier mput. The method can be used for many electrodes configuration.

  13. Triagem pré-participação com ECG em recrutas militares

    Directory of Open Access Journals (Sweden)

    Alon Grossman

    2013-03-01

    Full Text Available FUNDAMENTO: Os achados e investigações adicionais necessários com base na triagem pré-participação com eletrocardiograma (ECG entre os recrutas militares estão mal definidos na literatura. OBJETIVOS: Este estudo foi elaborado para avaliar a taxa de achados anormais na triagem pré-participação com ECG em adultos jovens e as avaliações adicionais necessárias com base nestes resultados. MÉTODOS: Um estudo de coorte retrospectivo foi realizado no centro aero-médico da Força Aérea de Israel (IAF, para candidatos das unidades das academias de voo e de tropa s de elite. Os candidatos das unidades das Academias de voo e de elite passam por uma triagem pré-participação com ECG antes do alistamento nas Forças de Defesa de Israel (IDF. Desde 2010, todos os ECGs são realizados no centro aero-médico da IAF. Todos os ECGs realizados desde janeiro de 2010 foram analisados por um de três cardiologistas e todos aqueles nos quais resultados significativos foram identificados foram encaminhados para uma avaliação mais detalhada, a pedido do cardiologista. As causas de encaminhamento para avaliação posterior, as avaliações realizadas e os resultados dessas avaliações são notificados para a população de estudo. RESULTADOS: 1.455 ECGs foram realizados nos anos 2010-2011. Desses, 1.388 (95,39% foram interpretadas como normais. 67 indivíduos foram encaminhados para uma avaliação mais detalhada com base nos achados do ECG. Os achados mais comuns levando a uma avaliação mais detalhada foram alterações da onda T (16 casos, 23,88%, padrão de pré-excitação (14, 20,89% e critérios de voltagem para hipertrofia ventricular esquerda (11; 16,41%. Apenas 7 indivíduos (10,44% tinham resultados anormais que foram considerados clinicamente significativos no final da avaliação médica. CONCLUSÕES: A taxa de achados significantes levando à desqualificação para a atividade militar é extremamente baixa e o encaminhamento para

  14. Comparison between retrospective gating and ECG triggering in magnetic resonance velocity mapping

    DEFF Research Database (Denmark)

    Søndergaard, L; Ståhlberg, F; Thomsen, C

    1993-01-01

    ECG-triggered cinematographic studies of the cardiovascular system are hampered by several technical restrictions such as the inability to image end-diastole, ghosting, varying signal intensity, and phase contributions from eddy currents. Retrospective gating may solve these problems, but involves...... of flow pulses. However, by reducing the time window retrospectively gated flow measurements were in good agreement with those that are ECG triggered. When fulfilling the demand of a narrow time window for interpolation, retrospective gating offers several advantages in MR velocity mapping....

  15. Comparative study of T-amplitude features for fitness monitoring using the ePatch® ECG recorder

    DEFF Research Database (Denmark)

    Thorpe, Julia Rosemary; Saida, Trine; Mehlsen, Jesper

    2014-01-01

    This study investigates ECG features, focusing on T-wave amplitude, from a wearable ECG device as a potential method for fitness monitoring in exercise rehabilitation. An automatic T-peak detection algorithm is presented that uses local baseline detection to overcome baseline drift without the need...

  16. Prospective ECG triggering versus low-dose retrospective ECG-gated 128-channel CT coronary angiography: comparison of image quality and radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. Regression of ECG-LVH is associated with lower risk of new-onset heart failure and mortality in patients with isolated systolic hypertension; The LIFE study

    DEFF Research Database (Denmark)

    Larstorp, Anne Cecilie K; Okin, Peter M; Devereux, Richard B

    2012-01-01

    Hypertension and electrocardiographic left ventricular hypertrophy (ECG-LVH) are strong predictors of heart failure (HF). It is unclear whether regression of ECG-LVH during treatment predicts less new-onset HF in patients with isolated systolic hypertension (ISH)....

  18. Non-ECG-gated CT pulmonary angiography and the prediction of right ventricular dysfunction in patients suspected of pulmonary embolism

    DEFF Research Database (Denmark)

    Gutte, Henrik; Mortensen, Jann; Mørk, Mette Louise;

    2016-01-01

    PURPOSE: Right ventricular dysfunction (RVD) is an important prognostic factor of 30-day mortality in patients with acute pulmonary embolism (PE). The aim of our study was to evaluate whether non-electrocardiogram (ECG)-gated cardiovascular parameters attained during computed tomography pulmonary...... angiography (CTPA) could predict RVD in patients suspected of PE using ECG-gated cardiac CT angiography as reference. METHODS: Consecutive patients suspected of PE were referred to a ventilation/perfusion single-photon emission tomography (V/Q-SPECT) as first-line imaging procedure. Patients had a V....../Q-SPECT/CT, a CTPA and an ECG-gated cardiac CT angiography performed the same day. RESULTS: A total of 71 patients were available for analysis. Seventeen patients (24%) had RVD. The non-ECG-gated dimensions of left and right ventricle and the major vessels were correlated with ECG-gated cardiac dimensions. The size...

  19. Fractional Dynamical Model for the Generation of ECG like Signals from Filtered Coupled Van-der Pol Oscillators

    CERN Document Server

    Das, Saptarshi

    2014-01-01

    In this paper, an incommensurate fractional order (FO) model has been proposed to generate ECG like waveforms. Earlier investigation of ECG like waveform generation is based on two identical Van-der Pol (VdP) family of oscillators which are coupled by time delays and gains. In this paper, we suitably modify the three state equations corresponding to the nonlinear cross-product of states, time delay coupling of the two oscillators and low-pass filtering, using the concept of fractional derivatives. Our results show that a wide variety of ECG like waveforms can be simulated from the proposed generalized models, characterizing heart conditions under different physiological conditions. Such generalization of the modelling of ECG waveforms may be useful to understand the physiological process behind ECG signal generation in normal and abnormal heart conditions. Along with the proposed FO models, an optimization based approach is also presented to estimate the VdP oscillator parameters for representing a realistic ...

  20. Convulsive syncope resulting from arrhythmia in a case of congenital deafness with ECG abnormalities

    NARCIS (Netherlands)

    Bruggen, H.W. van; Sebus, J.; Heyst, A.N.P. van

    1969-01-01

    A description is given of an 8-year-old girl with the syndrome of Jervell and Lange Nielsen consisting of congenital deafness, prolonged Q-T time in the ECG, and attacks of unconsciousness. In addition there were extrasystoles, ventricular tachycardia, ventricular fibrillation, and atrial flutter. T

  1. 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.

  2. Using statistical distances to detect changes in the normal behavior of ECG-Holter signals

    Science.gov (United States)

    Bastos de Figueiredo, Julio C.; Furuie, Sergio S.

    2001-05-01

    One of the main problems in the study of complex systems is to define a good metric that can distinguish between different dynamical behaviors in a nonlinear system. In this work we describe a method to detect different types of behaviors in a long term ECG-Holter using short portions of the Holter signal. This method is based on the calculation of the statistical distance between two distributions in a phase-space of a dynamical system. A short portion of an ECG-Holter signal with normal behavior is used to reconstruct the trajectory of an attractor in low dimensional phase-space. The points in this trajectory are interpreted as statistical distributions in the phase-space and assumed to represent the normal dynamical behavior of the ECG recording in this space. A fast algorithm is then used to compute the statistical distance between this attractor and all other attractors that are built using a sliding temporal window over the signal. For normal cases the distance stayed almost constant and below a threshold. For cases with abnormal transients, on the abnormal portion of ECG, the distance increased consistently with morphological changes.

  3. Automatic detection of ECG electrode misplacement: a tale of two algorithms.

    Science.gov (United States)

    Xia, Henian; Garcia, Gabriel A; Zhao, Xiaopeng

    2012-09-01

    Artifacts in an electrocardiogram (ECG) due to electrode misplacement can lead to wrong diagnoses. Various computer methods have been developed for automatic detection of electrode misplacement. Here we reviewed and compared the performance of two algorithms with the highest accuracies on several databases from PhysioNet. These algorithms were implemented into four models. For clean ECG records with clearly distinguishable waves, the best model produced excellent accuracies (> = 98.4%) for all misplacements except the LA/LL interchange (87.4%). However, the accuracies were significantly lower for records with noise and arrhythmias. Moreover, when the algorithms were tested on a database that was independent from the training database, the accuracies may be poor. For the worst scenario, the best accuracies for different types of misplacements ranged from 36.1% to 78.4%. A large number of ECGs of various qualities and pathological conditions are collected every day. To improve the quality of health care, the results of this paper call for more robust and accurate algorithms for automatic detection of electrode misplacement, which should be developed and tested using a database of extensive ECG records.

  4. An ultra-low power (ULP) bandage-type ECG sensor for efficient cardiac disease management.

    Science.gov (United States)

    Shin, Kunsoo; Park, G G; Kim, J P; Lee, T H; Ko, B H; Kim, Y H

    2013-01-01

    This paper proposed an ultra-low power bandage-type ECG sensor (the size: 76 × 34 × 3 (mm(3)) and the power consumption: 1 mW) which allows for a continuous and real-time monitoring of a user's ECG signals over 24h during daily activities. For its compact size and lower power consumption, we designed the analog front-end, the SRP (Samsung Reconfigurable Processor) based DSP of 30 uW/MHz, and the ULP wireless RF of 1 nJ/bit. Also, to tackle motion artifacts(MA), a MA monitoring technique based on the HCP (Half-cell Potential) is proposed which resulted in the high correlation between the MA and the HCP, the correlation coefficient of 0.75 ± 0.18. To assess its feasibility and validity as a wearable health monitor, we performed the comparison of two ECG signals recorded form it and a conventional Holter device. As a result, the performance of the former is a little lower as compared with the latter, although showing no statistical significant difference (the quality of the signal: 94.3% vs 99.4%; the accuracy of arrhythmia detection: 93.7% vs 98.7%). With those results, it has been confirmed that it can be used as a wearable health monitor due to its comfortability, its long operation lifetime and the good quality of the measured ECG signal.

  5. ECG of the "Newborn" Mouse (Mus domesticus) with Specific Reference to Comparative AV Transmission

    NARCIS (Netherlands)

    Tweel, L.H. van der; Strackee, J.; Stokhof, A.A.; Wassenaar, C.; Meijler, F.L.

    1999-01-01

    The objective of this study was to record the ECG of the smallest living mammal to extend the domain of data for comparative AV-nodal electrophysiologic purposes. These data are needed to establish the relationship between the PR interval and heart size in mammalian species of all sizes. Methods and

  6. An Autonomous Wireless Sensor Node With Asynchronous ECG Monitoring in 0.18 μ m CMOS.

    Science.gov (United States)

    Mansano, Andre L; Li, Yongjia; Bagga, Sumit; Serdijn, Wouter A

    2016-06-01

    The design of a 13.56 MHz/402 MHz autonomous wireless sensor node with asynchronous ECG monitoring for near field communication is presented. The sensor node consists of an RF energy harvester (RFEH), a power management unit, an ECG readout, a data encoder and an RF backscattering transmitter. The energy harvester supplies the system with 1.25 V and offers a power conversion efficiency of 19% from a -13 dBm RF source at 13.56 MHz. The power management unit regulates the output voltage of the RFEH to supply the ECG readout with VECG = 0.95 V and the data encoder with VDE = 0.65 V . The ECG readout comprises an analog front-end (low noise amplifier and programmable voltage to current converter) and an asynchronous level crossing ADC with 8 bits resolution. The ADC output is encoded by a pulse generator that drives a backscattering transmitter at 402 MHz. The total power consumption of the sensor node circuitry is 9.7 μ W for a data rate of 90 kb/s and a heart rate of 70 bpm. The chip has been designed in a 0.18 μm CMOS process and shows superior RF input power sensitivity and lower power consumption when compared to previous works.

  7. Efficient ECG signal analysis using wavelet technique for arrhythmia detection: an ANFIS approach

    Science.gov (United States)

    Khandait, P. D.; Bawane, N. G.; Limaye, S. S.

    2010-02-01

    This paper deals with improved ECG signal analysis using Wavelet Transform Techniques and employing subsequent modified feature extraction for Arrhythmia detection based on Neuro-Fuzzy technique. This improvement is based on suitable choice of features in evaluating and predicting life threatening Ventricular Arrhythmia . Analyzing electrocardiographic signals (ECG) includes not only inspection of P, QRS and T waves, but also the causal relations they have and the temporal sequences they build within long observation periods. Wavelet-transform is used for effective feature extraction and Adaptive Neuro-Fuzzy Inference System (ANFIS) is considered for the classifier model. In a first step, QRS complexes are detected. Then, each QRS is delineated by detecting and identifying the peaks of the individual waves, as well as the complex onset and end. Finally, the determination of P and T wave peaks, onsets and ends is performed. We evaluated the algorithm on several manually annotated databases, such as MIT-BIH Arrhythmia and CSE databases, developed for validation purposes. Features based on the ECG waveform shape and heart beat intervals are used as inputs to the classifiers. The performance of the ANFIS model is evaluated in terms of training performance and classification accuracies and the results confirmed that the proposed ANFIS model has potential in classifying the ECG signals. Cross validation is used to measure the classifier performance. A testing classification accuracy of 95.13% is achieved which is a significant improvement.

  8. Optimized pacing mode for hypertrophic cardiomyopathy: Impact of ECG fusion during pacing

    NARCIS (Netherlands)

    Berruezo, A.; Penela, D.; Burgos, F.; Evertz, R.; Fernandez-Armenta, J.; Roca, J.; Doltra, A.; Acosta, J.; Francino, A.; Sitges, M.; Alsina, X.; Ordonez, A.; Villuendas, R.; Brugada, R.; Mont, L.; Brugada, J.

    2015-01-01

    BACKGROUND: Electrocardiographic (ECG) fusion with intrinsic QRS could reduce the benefit of atrial synchronous biventricular pacing (AS-BiVP) in patients with hypertrophic obstructive cardiomyopathy (HOCM). OBJECTIVES: The purpose of this study was to assess the benefit of AS-BiVP and the influence

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

    NARCIS (Netherlands)

    Schut, Marleen H.; Tuinenbreijer, Kees; Broek, van den Egon L.; 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 e

  10. A mobile phone-based ecg and heart sound monitoring system - biomed 2011.

    Science.gov (United States)

    Iwamoto, Junichi; Ogawa, Hidekuni; Maki, Hiromichi; Yonezawa, Yoshiharu; Hahn, Allen W; Caldwell, W Morton

    2011-01-01

    We have developed a telemedicine system to monitor a patient’s electrocardiogram (ECG) and heart sounds (PCG) during daily activity. The complete system, consisting of an ECG recorder, an accelerometer and a 2.4 GHz low power mobile phone, is mounted on three chest sensing electrodes. The accelerometer records the PCG produced by closing of the mitral and aortic valves (S1 and S2). The sampled ECG and PCG are stored in the system for two minutes and continuously updated. When a patient feels heart discomfort such as angina or an arrhythmia, he/she pushes the data transmission switch on the system. The ECG and PCG for the next two minutes are stored in the system, and then the system then sends the four minutes of stored data directly to a hospital server computer via the 1.9 GHz low power mobile phone. These data are stored on the server and then downloaded to the physician’s Java configured mobile phone. The physician can then check the patient’s cardiac condition, regardless of patient or physician locations, and then take appropriate actions.

  11. Unusual QRS morphology on ECG: a rare condition and an interesting response to pacing.

    Science.gov (United States)

    Gula, Lorne J; Eckart, Robert E; Klein, George J; Peralta, Adelqui

    2005-08-01

    We present the interesting case of a young man with borderline wide QRS complexes noted on electrocardiogram (ECG). The diagnosis of an unusual form of preexcitation was reached using observations from intracardiac tracings at electrophysiology study. Atrial pacing consistently resulted in further widening of the first conducted QRS complex, and the physiology underlying this unusual finding is explored.

  12. 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.

  13. FPGA-core defibrillator using wavelet-fuzzy ECG arrhythmia classification.

    Science.gov (United States)

    Nambakhsh, Mohammad; Tavakoli, Vahid; Sahba, Nima

    2008-01-01

    An electrocardiogram (ECG) feature extraction and classification system has been developed and evaluated using Quartus II 7.1 belong to Altera Ltd. In wavelet domain QRS complexes were detected and each complex was used to locate the peaks of the individual waves. Then, fuzzy classifier block used these features to classify ECG beats. Three types of arrhythmias and abnormalities were detected using the procedure. The completed algorithm was embedded into Field Programmable Gate Array (FPGA). The completed prototype was tested through software-generated signals, in which test scenarios covering several kinds of ECG signals on MIT-BIH Database. For the purpose of feeding signals into the FPGA, a software was designed to read signal files and import them to the LPT port of computer that was connected to FPGA. From the results, it was achieved that the proposed prototype could do real time monitoring of ECG signal for arrhythmia detection. We also implemented algorithm in a sequential structure device like AVR microcontroller with 16 MHZ clock for the same purpose. External clock of FPGA is 50 MHZ and by utilizing of Phase Lock Loop (PLL) component inside device, it was possible to increase the clock up to 1.2 GHZ in internal blocks. Final results compare speed and cost of resource usage in both devices. It shows that in cost of more resource usage, FPGA provides higher speed of computation; because FPGA makes the algorithm able to compute most parts in parallel manner.

  14. [Changes in ECG indicators during bicycle ergometry in patients having suffered myocardial infarction].

    Science.gov (United States)

    Kheifets, Z N

    1984-01-01

    Altogether 218 patients with a history of myocardial infarction were subjected to bicycle ergometry. The ECG recorded at the height of the exercise showed a significant increase in the heart rate and in the amplitudes of P and R waves. The diastole and electric systole shortened. As the load was raised, the rate of A-B conduction was relatively decelerated.

  15. ECG signal compression using combined modified discrete cosine and discrete wavelet transforms.

    Science.gov (United States)

    Ahmed, S M; Al-Ajlouni, A F; Abo-Zahhad, M; Harb, B

    2009-01-01

    A new hybrid two-stage electrocardiogram (ECG) signal compression method based on the modified discrete cosine transform (MDCT) and discrete wavelet transform (DWT) is proposed. The ECG signal is partitioned into blocks and the MDCT is applied to each block to decorrelate the spectral information. Then, the DWT is applied to the resulting MDCT coefficients. Removing spectral redundancy is achieved by compressing the subordinate components more than the dominant components. The resulting wavelet coefficients are then thresholded and compressed using energy packing and binary-significant map coding technique for storage space saving. Experiments on ECG records from the MIT-BIH database are performed with various combinations of MDCT and wavelet filters at different transformation levels, and quantization intervals. The decompressed signals are evaluated using percentage rms error (PRD) and zero-mean rms error (PRD(1)) measures. The results showed that the proposed method provides low bit-rate and high quality of the reconstructed signal. It offers average compression ratio (CR) of 21.5 and PRD of 5.89%, which would be suitable for most monitoring and diagnoses applications. Simulation results show that the proposed method compares favourably with various state-of-the-art ECG compressors.

  16. Cost-effectiveness analysis of computerized ECG interpretation system in an ambulatory health care organization.

    Science.gov (United States)

    Carel, R S

    1982-04-01

    The cost-effectiveness of a computerized ECG interpretation system in an ambulatory health care organization has been evaluated in comparison with a conventional (manual) system. The automated system was shown to be more cost-effective at a minimum load of 2,500 patients/month. At larger monthly loads an even greater cost-effectiveness was found, the average cost/ECG being about $2. In the manual system the cost/unit is practically independent of patient load. This is primarily due to the fact that 87% of the cost/ECG is attributable to wages and fees of highly trained personnel. In the automated system, on the other hand, the cost/ECG is heavily dependent on examinee load. This is due to the relatively large impact of equipment depreciation on fixed (and total) cost. Utilization of a computer-assisted system leads to marked reduction in cardiologists' interpretation time, substantially shorter turnaround time (of unconfirmed reports), and potential provision of simultaneous service at several remotely located "heart stations."

  17. A modular low-complexity ECG delineation algorithm for real-time embedded systems.

    Science.gov (United States)

    Bote, Jose Manuel; Recas, Joaquin; Rincon, Francisco; Atienza, David; Hermida, Roman

    2017-02-17

    This work presents a new modular and lowcomplexity algorithm for the delineation of the different ECG waves (QRS, P and T peaks, onsets and end). Involving a reduced number of operations per second and having a small memory footprint, this algorithm is intended to perform realtime delineation on resource-constrained embedded systems. The modular design allows the algorithm to automatically adjust the delineation quality in run time to a wide range of modes and sampling rates, from a Ultra-low power mode when no arrhythmia is detected, in which the ECG is sampled at low frequency, to a complete High-accuracy delineation mode in which the ECG is sampled at high frequency and all the ECG fiducial points are detected, in case of arrhythmia. The delineation algorithm has been adjusted using the QT database, providing very high sensitivity and positive predictivity, and validated with the MIT database. The errors in the delineation of all the fiducial points are below the tolerances given by the Common Standards for Electrocardiography (CSE) committee in the High-accuracy mode, except for the P wave onset, for which the algorithm is above the agreed tolerances by only a fraction of the sample duration. The computational load for the ultra-low-power 8-MHz TI MSP430 series microcontroller ranges from 0.2 to 8.5% according to the mode used.

  18. Evaluation of Digital Compressed Sensing for Real-Time Wireless ECG System with Bluetooth low Energy.

    Science.gov (United States)

    Wang, Yishan; Doleschel, Sammy; Wunderlich, Ralf; Heinen, Stefan

    2016-07-01

    In this paper, a wearable and wireless ECG system is firstly designed with Bluetooth Low Energy (BLE). It can detect 3-lead ECG signals and is completely wireless. Secondly the digital Compressed Sensing (CS) is implemented to increase the energy efficiency of wireless ECG sensor. Different sparsifying basis, various compression ratio (CR) and several reconstruction algorithms are simulated and discussed. Finally the reconstruction is done by the android application (App) on smartphone to display the signal in real time. The power efficiency is measured and compared with the system without CS. The optimum satisfying basis built by 3-level decomposed db4 wavelet coefficients, 1-bit Bernoulli random matrix and the most suitable reconstruction algorithm are selected by the simulations and applied on the sensor node and App. The signal is successfully reconstructed and displayed on the App of smartphone. Battery life of sensor node is extended from 55 h to 67 h. The presented wireless ECG system with CS can significantly extend the battery life by 22 %. With the compact characteristic and long term working time, the system provides a feasible solution for the long term homecare utilization.

  19. [Study on mobile phone based wireless ECG monitoring technology system realization and performance test].

    Science.gov (United States)

    Yu, Yang; Liu, Jing

    2010-11-01

    This paper introduces a novel mobile phone based wireless real-time ECG monitoring system. And experiments were conducted to demonstrate the reliability and stability of the device. This novel system not only addresses the contradiction between continuous monitoring and device cost, but also represents advanced concepts of low cost medicine and personal health management.

  20. Sistema microcontrolado para transmissão de sinais de ECG pela internet

    OpenAIRE

    Bonho, Samir

    2006-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Elétrica. Este trabalho aborda o projeto e desenvolvimento de um sistema de telemedicina para eletrocardiograma (ECG), composto por um módulo de

  1. Interpretation of Normal and Pathological ECG Beats using Multiresolution Wavelet Analysis

    Directory of Open Access Journals (Sweden)

    Shubhada S.Ardhapurkar

    2012-12-01

    Full Text Available The Discrete wavelet transform has great capability to analyse the temporal and spectral properties of non stationary signal like ECG. In this paper, we have developed and evaluated a robust algorithm using multiresolution analysis based on the discrete wavelet transform (DWT for twelve-lead electrocardiogram (ECG temporal feature extraction. In the first step, ECG was denoised considerably by employing kernel density estimation on subband coefficients then QRS complexes were detected. Further, by selecting appropriate coefficients and applying wave segmentation strategy P and T wave peaks were detected. Finally, the determination of P and T wave onsets and ends was performed. The novelty of this approach lies in detection of different morphologies in ECG wave with few decision rules. We have evaluated the algorithm on normal and abnormal beats from various manually annotated databases from physiobank having different sampling frequencies. The QRS detector obtained a sensitivity of 99.5% and a positive predictivity of 98.9% over the first lead of the MIT-BIH Arrhythmia Database.

  2. ECG Rhythm Analysis with Expert and Learner-Generated Schemas in Novice Learners

    Science.gov (United States)

    Blissett, Sarah; Cavalcanti, Rodrigo; Sibbald, Matthew

    2015-01-01

    Although instruction using expert-generated schemas is associated with higher diagnostic performance, implementation is resource intensive. Learner-generated schemas are an alternative, but may be limited by increases in cognitive load. We compared expert- and learner-generated schemas for learning ECG rhythm interpretation on diagnostic accuracy,…

  3. 心电图在诊断急性心肌梗死的应用价值%Application value of ECG in the diagnosis of acute myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    翁娟

    2015-01-01

    AIM:To study the application value of electrocardi⁃ogram ( ECG ) in the diagnosis of acute myocardial infarction. METHODS:A total of 36 patients with acute myocardial infarc⁃tion were selected in our hospital from August 2013 to August 2014, and the ECG data were analyzed retrospectively. RE⁃SULTS:By using ECG, a total of 33 cases were diagnosed as myocardial infarction, with the positive rate being 91. 7%;3 ca⁃ses were misdiagnosed, accounting for 8. 3%. Among the diag⁃nosed patients, 18 cases were diagnosed as inferior wall myocardi⁃al infarction, 12 cases right ventricular myocardial infarction, and 6 cases non Q wave myocardial infarction. CONCLUSION:ECG was more accurate in diagnosing acute myocardial infarction, es⁃pecially myocardial infarction without ache of the anterior area. By clinical analysis and intensive observation of ECG, acute myocar⁃dial infarction can be affectively diagnosed. ECG is of great value in clinical application.%目的:研究分析心电图在诊断急性心肌梗死中的应用价值.方法:选取我院2013⁃08/2014⁃08收治的36例急性心肌梗死的患者,对患者的心电图诊断资料进行回顾性分析.结果:通过心电图检查出心肌梗死33例,其检出率为91.7%;漏诊3例,占8.3%.其中检出下壁心肌梗死18例,右室心肌梗死12例,非Q波型心肌梗死6例.结论:急性心肌梗死患者,采用心电图诊断的准确率较高,尤其是无心前区疼痛的心肌梗死疾病,通过分析患者的临床情况,密切观察心电图的变化,可以有效地诊断急性心肌梗死,其具有较高的临床应用价值.

  4. Electrocardiogram(ECG)and Cardiovascular Risk Factors Diagnostic Value of Coronary Artery Disease%心电图和心血管危险因素诊断冠心病的价值探讨

    Institute of Scientific and Technical Information of China (English)

    朱黎明

    2013-01-01

    Objective To study the patients with coronary heart disease(CHD)of conventional electrocardiogram(ECG)and the risk factors and the relationship between coronary artery angiography(the CAG),to help diagnosis and guiding treatment. Methods 105 cases of clinical risk factors for CHD patients and ECG compared with the CAG results were retrospectively analyzed. Results 105 patients in 78 cases,the CAG positie ECG ST-T change in 81 cases,in the CAG positive ECG without ST-T change in 20 cases,58 cases ECG ST-T change,the more risk factors for the CAG positive rate is higher. Conclusion Clinical basis for ECG ST-T change in the diagnosis of coronary heart disease should be careful,should be combined with risk factors and the CAG and so on carries on the system analysis,in order to improve the diagnostic accuracy.%目的:探讨冠心病(CHD)患者常规心电图(ECG)及危险因素与冠状动脉造影(CAG)的关系,从而帮助诊断与指导治疗。方法对105例拟诊CHD患者的危险因素及ECG与CAG结果进行回顾性对比分析。结果105例患者中CAG阳性者78例,ECG有ST-T改变81例,在CAG阳性者中ECG无ST-T改变20例,ECG有ST-T改变58例,危险因素越多CAG阳性率越高。结论临床依据心电图ST-T改变诊断冠心病应慎重,应结合危险因素及CAG等进行系统分析,以提高诊断的准确率。

  5. A wavelet-based ECG delineation algorithm for 32-bit integer online processing

    Directory of Open Access Journals (Sweden)

    Chiari Lorenzo

    2011-04-01

    Full Text Available Abstract Background 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. Methods 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. Results 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. Conclusions The proposed algorithm exhibits reliable QRS detection as well as accurate ECG delineation, in spite of a simple structure built on integer linear algebra.

  6. Impact of heart rate and rhythm on radiation exposure in prospectively ECG triggered computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Luecke, Christian, E-mail: neep@gmx.de [University of Leipzig – Heart Center, Department of Diagnostic and Interventional Radiology, Strümpellstrasse 39, D-04289, Leipzig (Germany); Andres, Claudia; Foldyna, Borek [University of Leipzig – Heart Center, Department of Diagnostic and Interventional Radiology, Strümpellstrasse 39, D-04289, Leipzig (Germany); Nagel, Hans Dieter [Wissenschaft and Technik für die Radiologie, Buchhholz i.d.N (Germany); Hoffmann, Janine; Grothoff, Matthias; Nitzsche, Stefan; Gutberlet, Matthias; Lehmkuhl, Lukas [University of Leipzig – Heart Center, Department of Diagnostic and Interventional Radiology, Strümpellstrasse 39, D-04289, Leipzig (Germany)

    2012-09-15

    Purpose: To evaluate the influence of different heart rates and arrhythmias on scanner performance, image acquisition and applied radiation exposure in prospectively ECG triggered computed tomography (pCT). Materials and methods: An ECG simulator (EKG Phantom 320, Müller and Sebastiani Elektronik GmbH, Munich, Germany) was used to generate different heart rhythms and arrhythmias: sinus rhythm (SR) at 45, 60, 75, 90 and 120/min, supraventricular arrhythmias (e.g. sinus arrhythmia, atrial fibrillation) and ventricular arrhythmias (e.g. ventricular extrasystoles), pacemaker-ECGs, ST-changes and technical artifacts. The analysis of the image acquisition process was performed on a 64-row multidetector CT (Brilliance, Philips Medical Systems, Cleveland, USA). A prospectively triggered scan protocol as used for routine was applied (120 kV; 150 mA s; 0.4 s rotation and exposure time per scan; image acquisition predominantly in end-diastole at 75% R-R-interval, in arrythmias with a mean heart rate above 80/min in systole at 45% of the R-R-interval; FOV 25 cm). The mean dose length product (DLP) and its percentage increase from baseline (SR at 60/min) were determined. Result: Radiation exposure can increase significantly when the heart rhythm deviates from sinus rhythm. ECG-changes leading to a significant DLP increase (p < 0.05) were bifocal pacemaker (61%), pacemaker dysfunction (22%), SVES (20%), ventricular salvo (20%), and atrial fibrillation (14%). Significantly (p < 0.05) prolonged scan time (>8 s) could be observed in bifocal pacemaker (12.8 s), pacemaker dysfunction (10.7 s), atrial fibrillation (10.3 s) and sinus arrhythmia (9.3 s). Conclusion: In prospectively ECG triggered CT, heart rate and rhythm can provoke different types of scanner performance, which can significantly alter radiation exposure and scan time. These results might have an important implication for indication, informed consent and contrast agent injection protocols.

  7. Changes in ischaemic ECG abnormalities and subsequent risk of cardiovascular disease

    Science.gov (United States)

    Sawai, Takeshi; Imano, Hironori; Muraki, Isao; Hayama-Terada, Mina; Shimizu, Yuji; Cui, Renzhe; Kitamura, Akihiko; Kiyama, Masahiko; Okada, Takeo; Ohira, Tetsuya; Yamagishi, Kazumasa; Umesawa, Mitsumasa; Sankai, Tomoko; Iso, Hiroyasu

    2017-01-01

    Objective The prognostic importance of changes in ischaemic ECG abnormalities over time (especially ST-T abnormalities) among Asians has not been fully investigated. We examined the associations between changes in ischaemic abnormalities upon serial ECG (improvement, persistence, deterioration) and cardiovascular disease (CVD) risk. Methods A prospective study cohort was conducted with 9374 men and women aged 40–69 years in four communities. Participants had multiple ECGs at study entry and during the next 10 years, and were followed up for a median period of 23.0 years. Total CVD (stroke and coronary heart disease) was ascertained under systematic surveillance. ECG abnormalities were defined by the Minnesota Code, ST depression (Code4), abnormal T wave (Code5) and categorised into nine groups (no–no, no–minor, no–major, minor–no, minor–minor, minor–major, major–no, major–minor, major–major) by comparison with the point of entrance and maximum change. Results We documented 1196 CVD events. Compared with no–no abnormality, no–minor, minor–major and major–major in Code4, HRs (95% CI) adjusted for cardiovascular risk factors were 1.19 (1.00–1.42), 1.57 (1.15–2.12) and 1.87 (1.42–2.47). Similar results were observed in Code5. Conclusions Changes in ischaemic ECG abnormalities from none to minor, and minor to major, as well as persistent major abnormalities, were associated with an increased risk of CVD. PMID:28176973

  8. The application of root mean square electrocardiography (RMS ECG for the detection of acquired and congenital long QT syndrome.

    Directory of Open Access Journals (Sweden)

    Robert L Lux

    Full Text Available BACKGROUND: Precise measurement of the QT interval is often hampered by difficulty determining the end of the low amplitude T wave. Root mean square electrocardiography (RMS ECG provides a novel alternative measure of ventricular repolarization. Experimental data have shown that the interval between the RMS ECG QRS and T wave peaks (RTPK closely reflects the mean ventricular action potential duration while the RMS T wave width (TW tracks the dispersion of repolarization timing. Here, we tested the precision of RMS ECG to assess ventricular repolarization in humans in the setting of drug-induced and congenital Long QT Syndrome (LQTS. METHODS: RMS ECG signals were derived from high-resolution 24 hour Holter monitor recordings from 68 subjects after receiving placebo and moxifloxacin and from standard 12 lead ECGs obtained in 97 subjects with LQTS and 97 age- and sex-matched controls. RTPK, QTRMS and RMS TW intervals were automatically measured using custom software and compared to traditional QT measures using lead II. RESULTS: All measures of repolarization were prolonged during moxifloxacin administration and in LQTS subjects, but the variance of RMS intervals was significantly smaller than traditional lead II measurements. TW was prolonged during moxifloxacin and in subjects with LQT-2, but not LQT-1 or LQT-3. CONCLUSION: These data validate the application of RMS ECG for the detection of drug-induced and congenital LQTS. RMS ECG measurements are more precise than the current standard of care lead II measurements.

  9. The 20 Tera flop Erasmus Computing Grid (ECG)

    NARCIS (Netherlands)

    T.A. Knoch (Tobias); L.V. de Zeeuw (Luc)

    2009-01-01

    textabstractThe Set-Up of the 20 Teraflop Erasmus Computing Grid: To meet the enormous computational needs of live- science research as well as clinical diagnostics and treatment the Hogeschool Rotterdam and the Erasmus Medical Center are currently setting up one of the largest desktop computing gr

  10. The 20 Tera flop Erasmus Computing Grid (ECG).

    NARCIS (Netherlands)

    T.A. Knoch (Tobias); L.V. de Zeeuw (Luc)

    2006-01-01

    textabstractThe Set-Up of the 20 Teraflop Erasmus Computing Grid: To meet the enormous computational needs of live- science research as well as clinical diagnostics and treatment the Hogeschool Rotterdam and the Erasmus Medical Center are currently setting up one of the largest desktop computing gr

  11. An ECG waveform recognition algorithm based on geometric characteristics%一种基于几何特征的 ECG 波形识别算法

    Institute of Scientific and Technical Information of China (English)

    李锋; 陈美丽

    2015-01-01

    目的:ECG自动分析系统由两部分组成:波形识别和智能诊断。在实际应用中,心电波形识别是该系统的关键。波形识别的精确性和可靠性决定了心脏病诊断的可靠性。为提高波形识别的速率及准确度,本文提出一种基于几何特征的ECG波形识别算法。方法首先利用数字滤波算法对信号进行预处理,提高信号的信噪比,然后通过改进的二阶导数计算出数据的几何特征:点的斜率和运动趋势,并在此基础上,结合ECG波形的实际物理特征,利用算法实现T波、P波、QRS波群的起点、终点以及波峰波谷的自动识别。结果统计分析结果表明,本算法能够快速高效地识别ECG波形。同时将该算法与其他当前各种ECG波形识别算法进行对比,该识别算法在识别的精确性与阳性预测值方面具有更好的性能。结论本文提出的基于几何特征的ECG波形识别算法可以进一步提高当前ECG波形识别算法的性能。%Objective ECG analysis diagnosis system mainly consists of two phases: waveform recognition and intelligent diagnosis .Accuracy and reliability of ECG waveform recognition determine the diagnosis and treatment of heart disease .A waveform recognition algorithm based on geometric characteristics is proposed in this paper to improve the detection rate and accuracy of waveform recognition .Methods Firstly, signals are preprocessed to improve noise ratio by digital filtering algorithm .Secondly , we calculate certain geometric characteristics such as the slope and the movement tendency of points with improved second derivative.Finally, we can automatically recognize the onset , the offset, the peak and the trough of T wave , P wave, QRS complex with the actual physical characteristics of ECG waveform on the basis of the previous results.Results Statistical analysis shows that our method can recognize the ECG wave fast and effectively .We also compare this

  12. Evaluation of clinical and electrocardiographic changes during the euthanasia of horses

    DEFF Research Database (Denmark)

    Buhl, Rikke; Andersen, L.O.F.; Karlshøj, M.

    2013-01-01

    The objective of this prospective field study was to investigate whether commonly used criteria for clinical death occurred at the same time as cardiac death, as determined by electrocardiography. Specific ECG changes during euthanasia were also studied. Twenty-nine horses were euthanized...... with pentobarbital at two different dose rates and 15 of the 29 horses also received detomidine hydrochloride for sedation. ECG was recorded prior to and during euthanasia. Time to collapse, cessation of reflexes, heart sounds and asystole were recorded. ECG recordings were used to calculate RR intervals, PQ...... duration, QRS duration, distance from QRS complex to end of T wave corrected for HR (QTc interval), duration of T-wave from peak to end (TpeakTend) and amplitudes of T wave (Tpeak) before and during euthanasia. Differences between groups and ECG changes were evaluated using analysis of variance. Clinical...

  13. 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

  14. Acute chest pain in emergency room. Preliminary findings with 40-64-slice CT ECG-gated of the whole chest.

    Science.gov (United States)

    Coche, E

    2007-01-01

    ECG-gated MDCT of the entire chest represents the latest technical advance in the diagnostic work-up of atypical chest pain. The authors report their preliminary experience with the use of 40 and 64-slice CT in the emergency room and recommend to study only patients with moderate likelihood of coronary artery disease. ECG-gated MDCT of the entire chest will be preferentially performed on 64-slice MDCT rather than 40-slice MDCT because it enable to reduce the scan time (18 seconds versus 28 seconds acquisition time), the volume of contrast medium (82 mL + 15 mL versus 97 mL + 15 mL of highly concentrated contrast agent for a patient of 70 kgs) and radiation exposure (17 mSv versus 19 mSv). Approximately 1500 to 2000 of images are produced and need to be analysed on a dedicated workstation by a radiologist expert in cardiac and thoracic disorders. At the present time, only a few studies exist in the literature showing some promising results but further large clinical studies are needed before to implement such sophisticated protocol in emergency room.

  15. Applied research of pediatric pneumonia serum CK, CTnT levels andECG change characteristics in diagnosis and treatment of disease and prognostic evaluation

    Institute of Scientific and Technical Information of China (English)

    Ying Ma

    2015-01-01

    Objective: Through studying pneumonia infant's serum creatine kinase and troponin T level changes and combined with electrocardiogram analysis to discuss its meaning to pneumonia infant's clinical diagnosis and treatment. Method: 73 cases of pneumonia infants were selected as the study group in our hospital from January 2014 to June 2014, meanwhile 58 cases of healthy infants were selected as the control group, to proceed serum CK and CTnT and electrocardiogram examination of both groups. Results: Before treatment, ordinary pneumonia group's CK level raised (P>0.05),CK-MB and CTnT levels significantly raised (P0.05), ECG returned to normal; severe pneumonia group's CK level obviously returned to normal range (P>0.05), but CK-MB and CTnT levels still exist significant difference (P0.05), electrocardiogram also returned to normal, only sinus tachycardia and bundle branch block were difficult to return to normal. Conclusion: Serum CK, CK-MB and CTnT levels of pneumonia infants rise along with the aggravation of disease, and ECG level is abnormal, after treatment, most pneumonia infants are cured. This illustrates infant pneumonia could easily cause multiple organ system damage, especially myocardial injury, monitoring CK, CK-MB and CTnT levels, combined with electrocardiogram data has important reference value to the diagnosis of pneumonia.

  16. Detection of T-Wave Alternans in Body Surface ECG%体表心电图中T波交替现象的检测

    Institute of Scientific and Technical Information of China (English)

    许菲; 滕炯华; 张泾周

    2011-01-01

    Detection of T-wave alternans( TWA) is of great significance for prediction of malignant ventricular arrhythmias. Firstly, empirical mode decomposition ( EMD) -based denoising method was used to reduce noises and interference from body surface ECG. Then recognition of ECG characteristic points was achieved using wavelet transform ,and finally a method of extracting T-wave windows around the T-wave peaks was advanced. By analyzing the power spectrums of 128 consequent T-wave windows, it is indicated that the proposed method achieved the detection of microvolt TWA ,and it can be applied to clinical diagnosis of TWA.%T波交替(T-wave alternans,TWA)的检测对于预测室性心律失常有重要意义.本文首先利用基于经验模态分解(empirical mode decomposition,EMD)的降噪方法进行心电信号的降噪,然后采用小波变换进行心电信号特征点的识别,最后给出以T波峰值点为参考点提取T波窗口的方法.通过对连续的128个T波窗口进行功率谱分析证实,上述方法实现了微伏级TWA的检测,可用于TWA的临床诊断.

  17. Diagnostic accuracy of prospective ECG gated coronary computed tomography on a 256 slices scanner: Daily practice experience

    Directory of Open Access Journals (Sweden)

    Ahmed M. Fareed

    2014-03-01

    Conclusions: In a highly prevalence diseased population, prospective ECG-gated CTCA using 256-slice scanner is highly accurate for detection and quantification of the degree of coronary luminal stenosis in comparison to ICA.

  18. FPGA-based electrocardiography (ECG signal analysis system using least-square linear phase finite impulse response (FIR filter

    Directory of Open Access Journals (Sweden)

    Mohamed G. Egila

    2016-12-01

    Full Text Available This paper presents a proposed design for analyzing electrocardiography (ECG signals. This methodology employs highpass least-square linear phase Finite Impulse Response (FIR filtering technique to filter out the baseline wander noise embedded in the input ECG signal to the system. Discrete Wavelet Transform (DWT was utilized as a feature extraction methodology to extract the reduced feature set from the input ECG signal. The design uses back propagation neural network classifier to classify the input ECG signal. The system is implemented on Xilinx 3AN-XC3S700AN Field Programming Gate Array (FPGA board. A system simulation has been done. The design is compared with some other designs achieving total accuracy of 97.8%, and achieving reduction in utilizing resources on FPGA implementation.

  19. Implementation of a data packet generator using pattern matching for wearable ECG monitoring systems.

    Science.gov (United States)

    Noh, Yun Hong; Jeong, Do Un

    2014-07-15

    In this paper, a packet generator using a pattern matching algorithm for real-time abnormal heartbeat detection is proposed. The packet generator creates a very small data packet which conveys sufficient crucial information for health condition analysis. The data packet envelopes real time ECG signals and transmits them to a smartphone via Bluetooth. An Android application was developed specifically to decode the packet and extract ECG information for health condition analysis. Several graphical presentations are displayed and shown on the smartphone. We evaluate the performance of abnormal heartbeat detection accuracy using the MIT/BIH Arrhythmia Database and real time experiments. The experimental result confirm our finding that abnormal heart beat detection is practically possible. We also performed data compression ratio and signal restoration performance evaluations to establish the usefulness of the proposed packet generator and the results were excellent.

  20. Toward Improving Electrocardiogram (ECG) Biometric Verification using Mobile Sensors: A Two-Stage Classifier Approach.

    Science.gov (United States)

    Tan, Robin; Perkowski, Marek

    2017-02-20

    Electrocardiogram (ECG) signals sensed from mobile devices pertain the potential for biometric identity recognition applicable in remote access control systems where enhanced data security is demanding. In this study, we propose a new algorithm that consists of a two-stage classifier combining random forest and wavelet distance measure through a probabilistic threshold schema, to improve the effectiveness and robustness of a biometric recognition system using ECG data acquired from a biosensor integrated into mobile devices. The proposed algorithm is evaluated using a mixed dataset from 184 subjects under different health conditions. The proposed two-stage classifier achieves a total of 99.52% subject verification accuracy, better than the 98.33% accuracy from random forest alone and 96.31% accuracy from wavelet distance measure algorithm alone. These results demonstrate the superiority of the proposed algorithm for biometric identification, hence supporting its practicality in areas such as cloud data security, cyber-security or remote healthcare systems.

  1. An ECG electrode-mounted heart rate, respiratory rhythm, posture and behavior recording system.

    Science.gov (United States)

    Yoshimura, Takahiro; Yonezawa, Yoshiharu; Maki, Hiromichi; Ogawa, Hidekuni; Ninomiya, Ishio; Morton Caldwell, W

    2004-01-01

    R-R interval, respiration rhythm, posture and behavior recording system has been developed for monitoring a patient's cardiovascular regulatory system in daily life. The recording system consists of three ECG chest electrodes, a variable gain instrumentation amplifier, a dual axis accelerometer, a low power 8-bit single-chip microcomputer and a 1024 KB EEPROM. The complete system is mounted on the chest electrodes. R-R interval and respiration rhythm are calculated by the R waves detected from the ECG. Posture and behavior such as walking and running are detected from the body movements recorded by the accelerometer. The detected data are stored by the EEPROM and, after recording, are downloaded to a desktop computer for analysis.

  2. Design of ANC filter using modified cuckoo search technique for ECG signal enhancement

    Directory of Open Access Journals (Sweden)

    Shivika Goyal

    2016-09-01

    Full Text Available In this work, the design of an adaptive noise canceller (ANC filter is presented using modified cuckoo search (MCS optimization technique. The proposed scheme is applied for de-noising of ECG signals. Our simulation results reveal that the ANC filter based on MCS algorithm provides superior performance than other optimization techniques used to enhance the ECG signal. The performance of ANC filter is compared with other reported algorithms by evaluating the fidelity parameters such as the signal to noise ratio (SNR, maximum error (ME and mean square error (MSE. The proposed ANC filter design with MCS scheme gives 18% improvement in output SNR, 87% decrease in ME, and 85% reduction in MSE over the recently reported Hilbert Huang Transform (HHT technique.

  3. Simultaneous Greedy Analysis Pursuit for compressive sensing of multi-channel ECG signals.

    Science.gov (United States)

    Avonds, Yurrit; Liu, Yipeng; Van Huffel, Sabine

    2014-01-01

    This paper addresses compressive sensing for multi-channel ECG. Compared to the traditional sparse signal recovery approach which decomposes the signal into the product of a dictionary and a sparse vector, the recently developed cosparse approach exploits sparsity of the product of an analysis matrix and the original signal. We apply the cosparse Greedy Analysis Pursuit (GAP) algorithm for compressive sensing of ECG signals. Moreover, to reduce processing time, classical signal-channel GAP is generalized to the multi-channel GAP algorithm, which simultaneously reconstructs multiple signals with similar support. Numerical experiments show that the proposed method outperforms the classical sparse multi-channel greedy algorithms in terms of accuracy and the single-channel cosparse approach in terms of processing speed.

  4. Real Time Processing and Transferring ECG Signal by a Mobile Phone.

    Science.gov (United States)

    Raeiatibanadkooki, Mahsa; Quachani, Saeed Rahati; Khalilzade, Mohammadmahdi; Bahaadinbeigy, Kambiz

    2014-12-01

    The real-time ECG signal processing system based on mobile phones is very effective in identifying continuous ambulatory patients. It could monitor cardiovascular patients in their daily life and warns them in case of cardiac arrhythmia. An ECG signal of a patient is processed by a mobile phone with this proposed algorithm. An IIR low-pass filter is used to remove the noise and it has the 55 Hz cutoff frequency and order 3. The obtained SNR showed a desirable noise removal and it helps physicians in their diagnosis. In this paper, Hilbert transform was used and the R peaks are important component to differ normal beats from abnormal ones. The results of sensitivity and positive predictivity of algorithm are 96.97% and 95.63% respectively. If an arrhythmia occurred, 4 seconds of this signal is displayed on the mobile phone then it will be sent to a remote medical center by TCP/IP protocol.

  5. [The Study of the Measurement of Heart Rate Variability Using ECG and Photoplethysmographic Signal].

    Science.gov (United States)

    Wang, Buqing; Chai, Xiaoke; Zhang Zhengbo; Wang, Weidong

    2015-07-01

    In comparison with the measurement of heart rate variability from ECG and from photoplethysmographic signal from 46 healthy adults in their spontaneous breathing state. The beat-to-beat intervals in ECG and pulse-to-pulse intervals in photoplethysmographic signal are extracted, and then the parameters of heart rate variability are calculated. Three kinds of algorithms are chosen to get the pulse-to-pulse intervals, which are the intervals of maximum of second derivative, the maximum of PPG signal and the tangent intersection. The results show that the correlation coefficients of the HRV parameters in the two calculation methods are highly correlated. The Bland-Altman scattered plots show the relative bias results from the algorithm of the maximum of PPG signal are smallest and singular points that deviate from the consistent limits are the least compared with the other two algorithms.

  6. Extraction of fetal heart rate from maternal surface ECG with provisions for multiple pregnancies.

    Science.gov (United States)

    Fanelli, A; Signorini, M G; Heldt, T

    2012-01-01

    Twin pregnancies carry an inherently higher risk than singleton pregnancies due to the increased chances of uterine growth restriction. It is thus desirable to monitor the wellbeing of the fetuses during gestation to detect potentially harmful conditions. The detection of fetal heart rate from the maternal abdominal ECG represents one possible approach for noninvasive and continuous fetal monitoring. Here, we propose a new algorithm for the extraction of twin fetal heart rate signals from maternal abdominal ECG recordings. The algorithm detects the fetal QRS complexes and converts the QRS onset series into a binary signal that is then recursively scanned to separate the contributions from the two fetuses. The algorithm was tested on synthetic singleton and twin abdominal recordings. It achieved an average sensitivity and accuracy for QRS complex detection of 97.5% and 93.6%, respectively.

  7. Correlation technique and least square support vector machine combine for frequency domain based ECG beat classification.

    Science.gov (United States)

    Dutta, Saibal; Chatterjee, Amitava; Munshi, Sugata

    2010-12-01

    The present work proposes the development of an automated medical diagnostic tool that can classify ECG beats. This is considered an important problem as accurate, timely detection of cardiac arrhythmia can help to provide proper medical attention to cure/reduce the ailment. The proposed scheme utilizes a cross-correlation based approach where the cross-spectral density information in frequency domain is used to extract suitable features. A least square support vector machine (LS-SVM) classifier is developed utilizing the features so that the ECG beats are classified into three categories: normal beats, PVC beats and other beats. This three-class classification scheme is developed utilizing a small training dataset and tested with an enormous testing dataset to show the generalization capability of the scheme. The scheme, when employed for 40 files in the MIT/BIH arrhythmia database, could produce high classification accuracy in the range 95.51-96.12% and could outperform several competing algorithms.

  8. Common mode noise cancellation for electrically non-contact ECG measurement system on a chair.

    Science.gov (United States)

    Keun Kim, Ko; Kyu Lim, Yong; Suk Park, Kwang

    2005-01-01

    Electrically non-contact ECG measurement system on a chair can be applied to a number of various fields for continuous health monitoring in daily life. However, the body is floated electrically for this system due to the capacitive electrodes and the floated body is very sensitive to the external noises or motion artifacts which affect the measurement system as the common mode noise. In this paper, the Driven-Seat-Ground circuit similar to the Driven-Right-Leg circuit is proposed to reduce the common mode noise. The analysis of this equivalent circuit is performed and the output signal waveforms are compared between with Driven-Seat-Ground and with capacitive ground. As the results, the Driven-Seat-Ground circuit improves significantly the properties of the fully capacitive ECG measurement system as the negative feedback.

  9. An ECG recording front-end with continuous-time level-crossing sampling.

    Science.gov (United States)

    Li, Yongjia; Mansano, Andre L; Yuan, Yuan; Zhao, Duan; Serdijn, Wouter A

    2014-10-01

    An ECG recording front-end with a continuous- time asynchronous level-crossing analog-to-digital converter (LC-ADC) is proposed. The system is a voltage and current mixed-mode system, which comprises a low noise amplifier (LNA), a programmable voltage-to-current converter (PVCC) as a programmable gain amplifier (PGA) and an LC-ADC with calibration DACs and an RC oscillator. The LNA shows an input referred noise of 3.77 μVrms over 0.06 Hz-950 Hz bandwidth. The total harmonic distortion (THD) of the LNA is 0.15% for a 10 mVPP input. The ECG front-end consumes 8.49 μW from a 1 V supply and achieves an ENOB up to 8 bits. The core area of the proposed front-end is 690 ×710 μm2, fabricated in a 0.18 μm CMOS technology.

  10. A level-crossing based QRS-detection algorithm for wearable ECG sensors.

    Science.gov (United States)

    Ravanshad, Nassim; Rezaee-Dehsorkh, Hamidreza; Lotfi, Reza; Lian, Yong

    2014-01-01

    In this paper, an asynchronous analog-to-information conversion system is introduced for measuring the RR intervals of the electrocardiogram (ECG) signals. The system contains a modified level-crossing analog-to-digital converter and a novel algorithm for detecting the R-peaks from the level-crossing sampled data in a compressed volume of data. Simulated with MIT-BIH Arrhythmia Database, the proposed system delivers an average detection accuracy of 98.3%, a sensitivity of 98.89%, and a positive prediction of 99.4%. Synthesized in 0.13 μm CMOS technology with a 1.2 V supply voltage, the overall system consumes 622 nW with core area of 0.136 mm (2), which make it suitable for wearable wireless ECG sensors in body-sensor networks.

  11. Minimally spaced electrode positions for multi-functional chest sensors: ECG and respiratory signal estimation

    Directory of Open Access Journals (Sweden)

    Klum Michael

    2016-09-01

    Full Text Available Unobtrusive medical instrumentation is a key in continuous patient monitoring. To increase compliance, multi-functional sensor concepts and measurement sites different from gold-standards are used. In this work, we aim to combine both approaches. We focus on minimally spaced electrode positions with high signal correlations to gold-standards. We present twofold experimental data from six and eleven healthy volunteers and provide chest positions with individual correlations up to 0.83 ± 0.06 for ECG and 0.73 ± 0.28 for the respiratory frequency. Using a performance index, we assess positions with correlations up to 0.77 ± 0.12 for ECG and 0.65 ± 0.35 for the respiratory frequency with 24 mm electrode distance.

  12. Custom FPGA processing for real-time fetal ECG extraction and identification.

    Science.gov (United States)

    Torti, E; Koliopoulos, D; Matraxia, M; Danese, G; Leporati, F

    2017-01-01

    Monitoring the fetal cardiac activity during pregnancy is of crucial importance for evaluating fetus health. However, there is a lack of automatic and reliable methods for Fetal ECG (FECG) monitoring that can perform this elaboration in real-time. In this paper, we present a hardware architecture, implemented on the Altera Stratix V FPGA, capable of separating the FECG from the maternal ECG and to correctly identify it. We evaluated our system using both synthetic and real tracks acquired from patients beyond the 20th pregnancy week. This work is part of a project aiming at developing a portable system for FECG continuous real-time monitoring. Its characteristics of reduced power consumption, real-time processing capability and reduced size make it suitable to be embedded in the overall system, that is the first proposed exploiting Blind Source Separation with this technology, to the best of our knowledge.

  13. Classification of ECG signals using LDA with factor analysis method as feature reduction technique.

    Science.gov (United States)

    Kaur, Manpreet; Arora, A S

    2012-11-01

    The analysis of ECG signal, especially the QRS complex as the most characteristic wave in ECG, is a widely accepted approach to study and to classify cardiac dysfunctions. In this paper, first wavelet coefficients calculated for QRS complex are taken as features. Next, factor analysis procedures without rotation and with orthogonal rotation (varimax, equimax and quartimax) are used for feature reduction. The procedure uses the 'Principal Component Method' to estimate component loadings. Further, classification has been done with a LDA classifier. The MIT-BIH arrhythmia database is used and five types of beats (normal, PVC, paced, LBBB and RBBB) are considered for analysis. Accuracy, sensitivity and positive predictivity are performance parameters used for comparing performance of feature reduction techniques. Results demonstrate that the equimax rotation method yields maximum average accuracy of 99.056% for unknown data sets among other used methods.

  14. VLSI implementation of a new LMS-based algorithm for noise removal in ECG signal

    Science.gov (United States)

    Satheeskumaran, S.; Sabrigiriraj, M.

    2016-06-01

    Least mean square (LMS)-based adaptive filters are widely deployed for removing artefacts in electrocardiogram (ECG) due to less number of computations. But they posses high mean square error (MSE) under noisy environment. The transform domain variable step-size LMS algorithm reduces the MSE at the cost of computational complexity. In this paper, a variable step-size delayed LMS adaptive filter is used to remove the artefacts from the ECG signal for improved feature extraction. The dedicated digital Signal processors provide fast processing, but they are not flexible. By using field programmable gate arrays, the pipelined architectures can be used to enhance the system performance. The pipelined architecture can enhance the operation efficiency of the adaptive filter and save the power consumption. This technique provides high signal-to-noise ratio and low MSE with reduced computational complexity; hence, it is a useful method for monitoring patients with heart-related problem.

  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. [Development of dynamic ECG acquisition and recording system: review and prospect].

    Science.gov (United States)

    Li, Suyi; Yang, Meiling; Ding, Mei; Lin, Guangda; Ling, Zhenbao

    2012-02-01

    Dynamic electrocardiography (DCG) or Holter is the best device to detect arrhythmia and can help early detection of some sudden cardiac death risk factors. The acquisition and recording system of the DCG, however, affects the data quality and the patients' comfort directly. This paper reviews the related latest studies, and discusses the importance of new ECG electrode and wireless dynamic monitoring in DCG monitoring field. Moreover, the existed main problems are summarized and classified and the prospects for the development trend are presented.

  17. 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

  18. Synthesize, optimize, analyze, repeat (SOAR): Application of neural network tools to ECG patient monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Watrous, R.; Towell, G.; Glassman, M.S. [Siemens Corporate Research, Princeton, NJ (United States)

    1995-12-31

    Results are reported from the application of tools for synthesizing, optimizing and analyzing neural networks to an ECG Patient Monitoring task. A neural network was synthesized from a rule-based classifier and optimized over a set of normal and abnormal heartbeats. The classification error rate on a separate and larger test set was reduced by a factor of 2. When the network was analyzed and reduced in size by a factor of 40%, the same level of performance was maintained.

  19. A new method for QRS complex detection in multichannel ECG: Application to self-monitoring of fetal health.

    Science.gov (United States)

    Varanini, Maurizio; Tartarisco, Gennaro; Balocchi, Rita; Macerata, Alberto; Pioggia, Giovanni; Billeci, Lucia

    2016-04-13

    This paper proposes a new approach for QRS complex detection in multichannel ECG and presents its application to fetal QRS (fQRS) detection in signals acquired from maternal abdominal leads. The method exploits the characteristics of pseudo-periodicity and time shape of QRS, it consists of devising a quality index (QI) which synthesizes these characteristics and of finding the linear combination of the acquired ECGs, which maximizes this QI. In the application for fQRS detection two QIs are devised, one QI (mQI) for maternal ECG (mECG) and one QI (fQI) for fetal ECG (fECG). The method is completely unsupervised and based on the following steps: signal pre-processing; maternal QRS-enhanced signal extraction by finding the linear combination that maximize the mQI; detection of maternal QRSs; mECG component approximation and canceling by weighted Singular Value Decomposition (SVD); fQRS-enhanced signal extraction by finding the linear combination that maximize the fQI and fQRS detection. The proposed method was compared with our previously developed Independent Component Analysis (ICA) based method as well as with simple mECG canceling and simple ICA methods. The comparison was carried out by evaluating the performances of the procedures in fQRS detection. The new method outperformed the results of the other approaches on the annotated open set of the Computing in Cardiology Challenge 2013 database. The proposed method seems to be promising for its implementation on portable device and for use in self-monitoring of fetal health in pregnant women.

  20. Evaluation of a Behind-the-Ear ECG Device for Smartphone Based Integrated Multiple Smart Sensor System in Health Applications

    Directory of Open Access Journals (Sweden)

    Numan Celik

    2016-07-01

    Full Text Available In this paper, we present a wireless Multiple Smart Sensor System (MSSS in conjunction with a smartphone to enable an unobtrusive monitoring of electrocardiogram (ear-lead ECG integrated with multiple sensor system which includes core body temperature and blood oxygen saturation (SpO2 for ambulatory patients. The proposed behind-the-ear device makes the system desirable to measure ECG data: technically less complex, physically attached to non-hair regions, hence more suitable for long term use, and user friendly as no need to undress the top garment. The proposed smart sensor device is similar to the hearing aid device and is wirelessly connected to a smartphone for physiological data transmission and displaying. This device not only gives access to the core temperature and ECG from the ear, but also the device can be controlled (removed and reapplied by the patient at any time, thus increasing the usability of personal healthcare applications. A number of combination ECG electrodes, which are based on the area of the electrode and dry/non-dry nature of the surface of the electrodes are tested at various locations near behind the ear. The best ECG electrode is then chosen based on the Signal-to-Noise Ratio (SNR of the measured ECG signals. These electrodes showed acceptable SNR ratio of ~20 db, which is comparable with existing tradition ECG electrodes. The developed ECG electrode systems is then integrated with commercially available PPG sensor (Amperor pulse oximeter and core body temperature sensor (MLX90614 using a specialized micro controller (Arduino UNO and the results monitored using a newly developed smartphone (android application.