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.

Despite the wide literature on R-wave detection algorithms for ECG Holter recordings, the long-term monitoring applications are bringing new requirements, and it is not clear that the existing methods can be straightforwardly used in those scenarios. Our aim in this work was twofold: First, we scrutinized the scope and limitations of existing methods for Holter monitoring when moving to long-term monitoring; Second, we proposed and benchmarked a beat detection method with adequate accuracy and usefulness in long-term scenarios. A longitudinal study was made with the most widely used waveform analysis algorithms, which allowed us to tune the free parameters of the required blocks, and a transversal study analyzed how these parameters change when moving to different databases. With all the above, the extension to long-term monitoring in a database of 7-day Holter monitoring was proposed and analyzed, by using an optimized simultaneous-multilead processing. We considered both own and public databases. In this new scenario, the noise-avoid mechanisms are more important due to the amount of noise that exists in these recordings, moreover, the computational efficiency is a key parameter in order to export the algorithm to the clinical practice. The method based on a Polling function outperformed the others in terms of accuracy and computational efficiency, yielding 99.48% sensitivity, 99.54% specificity, 99.69% positive predictive value, 99.46% accuracy, and 0.85% error for MIT-BIH arrhythmia database. We conclude that the method can be used in long-term Holter monitoring systems.

Angela Kornberger,1 Iris Burck,2 Hazem El Beyrouti,1 Nancy Halloum,1 Andres Beiras-Fernandez,1 Christian-Friedrich Vahl1 1Department of Cardiothoracic and Vascular Surgery, University Hospital of Johannes Gutenberg University, Mainz, Germany; 2Department of Diagnostic and Interventional Radiology, University Hospital of Johann Wolfgang Goethe University, Frankfurt am Main, Germany Background: False-positive diagnosis of acute Stanford type A aortic dissection (AAD) on computed tomography angiography (CTA) is still an issue and may lead to substantial consequences. Given that electrocardiography (ECG)-gated CTA provides greater diagnostic safety, it may be assumed that interhospital referrals with a diagnosis of AAD based on non-ECG-gated pre-referral CTA carry an elevated risk of false-positive diagnosis.Patients and methods: We reviewed a series of patients in whom a diagnosis of AAD based on non-ECG-gated pre-referral CTA was subsequently proven false by ECG-gated CTA. The artifacts that gave rise to the misdiagnosis, as well as the diagnostic pathways followed and the consequences of false-positive diagnosis were investigated.Results: In 5 patients, ECG-gated repeat CTA revealed artifacts in the pre-referral scans that had led to false-positive diagnosis and referral for emergent surgery. In the first case, the patient proceeded to surgery. In 4 subsequent cases, ECG-gated CTA was ordered because a false-positive diagnosis was suspected. We found that ECG-gated CTA rather than echocardiography provided sufficient information to rule out AAD in each of these cases. Comparison between pre-referral non-ECG-gated scans and ECG-gated repeat CTA demonstrated the wide range of artifacts that may give rise to a diagnosis of AAD.Conclusion: Patient condition permitting, the threshold to ECG-gated repeat CTA should be low when doubt arises with regard to a diagnosis of AAD based on non-ECG-gated CTA in interhospital referrals. Keywords: Stanford type A dissection, false-positive diagnosis, ECG-gated CTA

Background: Although powerful defibrillation devices are available in clinical practice, risk stratification is important in asymptomatic Brugada syndrome. In this study, vector-projected 187-channel electrocardiogram (VP-ECG) was used to calculate the ST-elevation score in Brugada-type ECG and test its usefulness in risk stratification. Methods and results: VP-ECG was recorded in 108 patients with Brugada-type ECG having ventricular fibrillation (VF) episodes (±; n=13/95). The ST morphologies were evaluated in 80/187 precordial leads. The coved- and saddleback types (4–6 vs. 1–3 points) of ST-elevation scores in 332 recordings were 58±57 points, which were calculated using virtual ECG leads. Compared with types 1–3 ECG patterns, the scores were significantly different among the groups (107±65, 62±45, and 14±22, respectively; p<0.01). In patients with VF (−), that is, asymptomatic Brugada syndrome, new VF occurrences, family history, or inducible VF showed a higher score than in those without these occurrences (p<0.01). Conclusion: The ST elevation score in VP-ECG objectively documented the degree of ST elevation in surface ECG in Brugada-type ECG patterns. The ST-elevation score might be useful for risk stratification in patients with asymptomatic Brugada syndrome.

<p>Abstract</p> <p>Background</p> <p>Aim of the study was to assess QTc interval by a 24-hour ECG recording in a group of HIV-infected individuals with a basal prolonged QTc. The risk factors associated with QTc prolongation and the indices of cardiovascular autonomic control were also evaluated.</p> <p>Methods</p> <p>A case–control study was performed using as cases 32 HIV-infected patients with prolonged (>440 msec) QTc interval as assessed by Holter ECG, and as controls 64 HIV-infected subjects with normal QTc interval. Autonomic function was evaluated by heart rate variability analysis during 24-hour recording.</p> <p>Results</p> <p>Duration of HIV disease was significantly longer among cases than among controls (p=0.04). Waist/hip ratio was also higher among cases than among controls (p=0.05). Frequency domain analysis showed the absence of physiologic decrease of low frequency (LF) in the night period in both cases and controls. The LF night in cases showed a statistically significant reduction when compared with controls (p=0.007).</p> <p>Conclusions</p> <p>In our study group, QTc interval prolongation was associated with a longer duration of HIV infection and with a greater waist/hip ratio. HIV patients with QTc interval prolongation and with a longer duration of HIV infection were more likely to have an impairment of parasympathetic and sympathetic cardiac component.</p>

Abstract: Abstract: The cardiac dynamics during meditation is explored quantitatively with two chaos-based non-linear techniques viz. multi-fractal detrended fluctuation analysis and visibility network analysis techniques. The data used are the instantaneous heart rate (in beats/minute) of subjects performing Kundalini Yoga and Chi meditation from PhysioNet. The results show consistent differences between the quantitative parameters obtained by both the analysis techniques. This indicates an interesting phenomenon of change in the complexity of the cardiac dynamics during meditation supported with quantitative parameters.The results also produce a preliminary evidence that these techniques can be used as a measure of physiological impact on subjects performing meditation.

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.

Conventional electrode-based technologies, such as the electrocardiogram (ECG), capture physiological signals using an electrolyte solution or gel that evaporates shortly after exposure, resulting in a decrease in the quality of the signal. Previously, we reported a novel dry impedimetric electrode using patterned vertically-aligned Carbon NanoTubes (pvCNT) for biopotential measurement applications. The mechanical adhesion strength of the pvCNT electrode to the substrate was weak, hence, we have improved this electrode using a thin coating of the conductive polymer polypyrrole (PPy) that strengthens its mechanical properties. Multiwall CNTs were grown vertically on a circular stainless-steel disc (⌀ = 10 mm) substrate of 50 &micro;m thickness forming patterned pillars on a square base (100 &micro;m &times; 100 &micro;m) with an inter-pillar spacing of 200 &micro;m and height up to 1.5 mm. The PPy coating procedure involves applying 10 &micro;L of PPy mixed with 70% ethyl alcohol solution and rapid drying at 300 &deg;C using a hot air gun at a distance of 10 cm. A comparative study demonstrated that the coated pvCNT had higher impedance compared to a non-coated pvCNT but lower impedance compared to the standard gel electrode. The PPy-coated pvCNT had comparable signal capture quality but stronger mechanical adhesion to the substrate.

A 60 year old man was found to have a heart murmur and ECG features of ventricular hypertrophy on a medical check up for military recruitment at age of 20, despite having swimming as the only exercise. His mother had 3 survived children out of 9 pregnancies.

Abstract Cardiovascular diseases are associated with high morbidity and mortality. However, it is still a challenge to diagnose them accurately and efficiently. Electrocardiogram (ECG), a bioelectrical signal of the heart, provides crucial information about the dynamical functions of the heart, playing an important role in cardiac diagnosis. As the QRS complex in ECG is associated with ventricular depolarization, therefore, accurate QRS detection is vital for interpreting ECG features. In this paper, we proposed a real-time, accurate, and effective algorithm for QRS detection. In the algorithm, a proposed preprocessor with a band-pass filter was first applied to remove baseline wander and power-line interference from the signal. After denoising, a method combining K-Nearest Neighbor (KNN) and Particle Swarm Optimization (PSO) was used for accurate QRS detection in ECGs with different morphologies. The proposed algorithm was tested and validated using 48 ECG records from MIT-BIH arrhythmia database (MITDB), achieved a high averaged detection accuracy, sensitivity and positive predictivity of 99.43, 99.69, and 99.72%, respectively, indicating a notable improvement to extant algorithms as reported in literatures.

Objectives: Ictal and interictal ECG abnormalities are not rare in patients with epilepsy. The diagnosis of those arrhythmias using video-EEG monitoring may provide help for prediction of lateralization-localization of epileptic focus and choosing apropriate antiepileptic drugs. The aim of our study was to define arrhythmias during simultaneous routine EEG-ECG recordings and to analyze the effect of these on the management of the patients.Methods: The keywords related to cardiac arrhythmia were searched in all EEG recording reports between January 2011 and February 2012. The demographic features, diagnosis, or pre-diagnosis of patients during routine EEG recordings were obtained from Hospital Data System. We also evaluated the EEG-ECG recordings of patients having arrhythmia and searched for long QT interval.Results: In all 2136 EEG reports, 48 (2%) of them included keywords related to cardiac arrhytmias. There were 25 females included in the study and the mean age of all was 53. Of the 48 patients, 18 had exstrasystole and 14 had tacycardia. Thirteen reports noted no details about the type of arrhythmia, and 3 patients had bloc or bradiarrhythmia. After routine EEG recordings, 6 patients underwent cardiology follow up in our center. One patient with an asystole during EEG recording received cardiac pacemaker inplant.Conclusion: The detection of cardiac arrhythmias is important in diagnosis and follow up of patients who are referred for routine EEG laboratory. Dedicating one channel to ECG recording can only take few minutes even in busy EEG laboratories and make big differences in some patients’ management.

<p><strong>Background and Objective: </strong>Increasing exposure to magnetic and electromagnetic fields is inevitable. This study evaluates effect of MRI on ECG parameters of patients.<strong> Methods:</strong> This is an analytic study conducted in 2015 in the Gonabad MRI center. Eighty-four patients referred to the MRI center were recruited by convenient sampling. Two-lead ECG was measured before and after MRI. MRI was done by Neusoft machine, made in China, with 0.35 Tesla magnetic fields. Data analysis was done by SPSS, version 14.5, using pairwise t-test and Wilcoxon test (p&lt;0.05). <strong>Results:</strong> Heart rate was 80.63 ± 10.41 beat/minutes before MRI and 71.58 ± 10.22 beat/minutes after MRI. QT interval was 9.70 ± 1.60 mm/s before MRI and 10.95 ± 0.93 mm/s before MRI (p&lt;0.001). P-wave duration was 2.16 ± 0.47 mm/s before MRI and 2.12 ± 0.38 mm/s after MRI (p=0.45). QRS wave duration was 1.88 ± 0.51 mm/s before MRI and 1.88 ± 0.51 mm/s after MRI (p=0.64). PR interval was 4.33 ± 0.92 mm/s before MRI and 4.33 ± 0.78 mm/s after MRI (p=0.89). <strong>Discussion:</strong><strong> </strong>Findings showed that 0.35-tesla MRI can increase QT interval and reduce heart rate; however, it is ineffective on P-wave duration, QRS and PR interval. To control the limitation, patients referred to MRI center for the second time were selected for the study. Moreover, the patients were kept under similar conditions before MRI to avoid moderate and severe anxiety. <strong>Conclusion:</strong> This study showed that 0.35 tesla MRI can reduce heart rate and increase QT interval. However, it is ineffective on P-wave duration, QRS and PR interval. Thus, it is suggested to measure these parameters before and after MRI. </p>

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.

Background: Hypertrophic cardiomyopathy (HCM) is a genetic disease associated with risk of morbidity and sudden cardiac death. The prevalence, hypertrophy patterns, mode of presentations, and different ECG findings vary in different regions of the world. To date, no data is present regarding these variables in Qatar. Patients and Methods: A retrospective, cross sectional, descriptive analysis of all patients referred for echocardiography study at Hamad General Hospital, Qatar. The study period was from January 2008 till December 2010. Aims: To study 1) the prevalence of HCM, 2) the different patterns of hypertrophy, and 3) the clinical and ECG presentations in this population. Results: Out of the 29,286 cases evaluated, 38 patients were found to have HCM (0.13%). Their clinical, ECG, and echocardiography findings were analyzed. Mean age was 47 y, 35 males (92%) and 3 females (8%). Four patterns of hypertrophy were described; 17 (44.7%) had septal hypertrophy alone, 6 (15.8%) had septal and other segments hypertrophy but sparing the apex, 10 (26.3%) had apical segments along with any other segment hypertrophy, and 5 (13.2%) had apical hypertrophy alone. No obstruction was found in 19 (50%), left ventricular outflow (LVO) tract obstruction was found in 13 (34%), and mid cavity obstruction (MCO) in 6 (16%). Twenty one (55.3%) patients were referred because of chest pain, 15 (39.5%) with palpitations, 15 (39.5%) with shortness of breath, and 5 (13.2%) with syncope. Nine patients (23.7%) were asymptomatic and were referred because of cardiac murmur during routine examination. ECG evidence of LV hypertrophy was found in 29 (76.3%). 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.

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.

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.

Abstract Introduction The analysis of electrocardiogram (ECG) signals allows the experts to diagnosis several cardiac disorders. However, the accuracy of such diagnostic depends on the signals quality. In this paper it is proposed a simple method for power-line interference (PLI) removal based on the wavelet decomposition, without the use of thresholding techniques. Methods This method consists in identifying the ECG and noise frequency range for further zeroing wavelet detail coefficients in the subbands with no ECG coefficients in the frequency content. Afterward, the enhanced ECG signal is obtained by the inverse discrete wavelet transform (IDWT). In order to choose the wavelet function, several experiments were performed with synthetic signals with worse Signal-to-Noise Ratio (SNR). Results Considering the relative error metrics and runtime, the best wavelet function for denoising was Symlet 8. Twenty synthetic ECG signals with different features and eight real ECG signals, obtained in the Physionet Challenge 2011, were used in the experiments. Results show the advantage of the proposed method against thresholding and notch filter techniques, considering classical metrics of assessment. The proposed method performed better for 75% of the synthetic signals and for 100% of the real signals considering most of the evaluation measures, when compared with a thresholding technique. In comparison with the notch filter, the proposed method is better for all signals. Conclusion The proposed method can be used for PLI removal in ECG signals with superior performance than thresholding and notch filter techniques. Also, it can be applied for high frequencies denoising even without a priori frequencies knowledge.

Patients with ST elevation myocardial infarction (STEMI) require prompt treatment, best done by primary percutaneous coronary intervention (PPCI). However, for patients unable to receive PPCI, immediate pre-hospital thrombolysis (PHT) is the best alternative. Evidence indicates that diagnostic and management support for staff increases the use of PHT. This study aimed to describe the patient demographics and management of patients, to determine any potential inter-area differences in referral rates to the ECG e-transmission service and to explore the views and experiences of key staff involved in ECG e-transmission within NHS Highland. Data from 2,025 patient episodes of ECG e-transmission identified a statistically significant geographical variation in ECG e-transmission and PHT delivery. Scottish Ambulance Service (SAS) staff were more likely than GPs to deliver PHT overall, however, GPs were more likely to deliver in remote areas. Interviews with six Cardiac Care Unit (CCU) nurses and six SAS staff highlighted their positive views of ECG e-transmission, citing perceived benefits to patients and interprofessional relationships. Poor access to network signal was noted to be a barrier to engaging in the system. This study has demonstrated that a specialist triage service based on e-transmission of ECGs in patients with suspected STEMI can be implemented in a diverse geographical setting. Work is needed to ensure equity of the service for all patients.

We investigated the variations in the magnetic field distribution and power transmission efficiency, resulting from changes in the relative positions of the transmitting and receiving coils, for electromagnetic induction-type wireless power transmission using an elliptical receive coil. Results of simulations using a high-frequency structure simulator were compared to actual measurement results. The simulations showed that the transmission efficiency could be maintained relatively stable even if the alignment between the transmitting and receiving coils was changed to some extent. When the centre of the receiving coil was perfectly aligned with the centre of the transmitting coil, the transmission efficiency was in the maximum; however, the degree of decrease in the transmission efficiency was small even if the centre of the receiving coil moved by ±10 mm from the centre of the transmitting coil. Therefore, it is expected that the performance of the wireless power transmission system will not be degraded significantly even if perfect alignment is not maintained. Animal experiments confirmed good ECG signals for the simulation conditions. The results suggested a standardized application method of wireless transmission in the utilization of wireless power for implantable sensors.

This study investigates the potential of a set of ECG morphological features for person verification/identification. The measurements are done over 145 pairs of ECG recordings from healthy subjects, acquired 5 years apart (T1, T2 = T1+5 years). Time, amplitude, area and slope descriptors of the QRS-T pattern are analysed in 4 ECG leads, forming quasi-orthogonal lead system (II&III, V1, V5). The correspondence between feature values in T1 and T2 is verified via factor analysis by principal components extraction method; correlation analysis applied over the measurements in T1 and T2; synthesis of regression equations for prediction of features’ values in T2 based on T1 measurements; and cluster analysis for assessment of the correspondence between measured and predicted feature values. Thus, 11 amplitude descriptors of the QRS complex are highlighted as stable, i.e. keeping their strong correlation (≥0.7) within a certain factor, weak correlation (<0.3) with the features from the remaining factors and presenting high correlation in the two measurement periods that is a sign for their person verification/identification potential. The observed coincidence between feature values measured in T2 and predicted via the designed regression models (r=0.93) suggests about the confidence of person identification via the proposed morphological features.

Background: To evaluate predictive value of heart rate turbulence (HRT), deceleration capacity (DC) and microvolt T-wave alternans (mTWA) for risk stratification for sudden cardiac death (SCD) in patients after myocardial infarction (MI) during 60 months of follow-up. Methods We studied 111 patients after MI occurred > 60 days (27 [9; 84] months) before enrollment (84 men; mean age 64.1±10.5 years). All subjects had 24-hour ambulatory ECG monitoring with HRT, DC and mTWA evaluation. Follow-up period was 60 months; primary endpoint was SCD, secondary endpoint included all non-sudden cardiovascular deaths. Results During follow-up, we registered 19 cases of SCD and 11 cases of non-sudden cardiovascular deaths (including 7 fatal MI and 3 fatal strokes). DC had high negative predictive value (97.4% for all-cause mortality and 93.7% for SCD). DC values below 4.15 for allcause mortality and 2.0 for SCD significantly increased risk of all-cause mortality (OR 8.5, 95% CI 2.9 to 24.6, <0.001) and SCD (OR 9.6, 95% CI 3.2 to 28.5, р<0.001). Combined risk assessment at 12 months revealed that the most significant combination was HRT2 and mTWA100 > 53 mcV, which increased risk both of all-cause mortality (30.7-fold) and SCD (63.3-fold); however, at 60 months this predictive value for SCD decreased (OR = 20.8 (95% CI 2.8 to 114.0), p <0.001). Conclusions Evaluation of HRT, DC and mTWA during 24-hour ECG monitoring may define the high risk of cardiovascular mortality and SCD in post-MI patients especially during the first 12 months after the baseline examination.

Several causes are known to induce the right precordial ST elevation mimicking Brugada syndrome. Right ventricular outflow area is assumed to be responsible for such ECG changes. We experienced a case of anterior mediastinal infective mass lesion with a Brugada-like ECG. A 52-year-old female, who has pulmonary stenosis and recurrent episodes of right ventricular heart failure, complained of high fever, abdominal discomfort, and edema. On physical examination, jugular vein dilation, hepatomegaly, and facial and leg edema were noted. Leucocytosis was also noted on blood examination. An ECG showed right ventricular hypertrophy, incomplete right bundle branch block pattern and marked ST elevation on precordial leads mimicking Brugada syndrome. Magnetic resonance imaging revealed an abnormal mass shadow located on the anterior mediastinum and compressing the right ventricle (Figure 1A). Trans-thoracic echocardiography also showed the high echogenic mass lesion at the anterior side of right ventricle and the vicinity of pulmonary valve. After treatment with antibiotics, the mass lesion gradually shrunk. Concomitantly, the ST elevation disappeared with improvement of inflammatory markers (Figure 1B). The symptoms suggesting right ventricular failure were also ameliorated. The mechanism of Brugada-like ST elevation in this patient was considered to be compression, by the abnormal infective mass, of the right ventricular outflow tract with/without focal pericardial inflammation.

هدف از این پژوهش بررسی اثر تزریق هورمون­های eCG، PGF2α و GnRH بر بهبود درصد باروری میشهای نژاد زندی همزمان سازی شده با سیدر در خارج فصل تولید مثل بوده است تا بتوان بازده تولید مثلی را در این دام بومی ایران افزایش داد. در این پژوهش 500 راس میش نژاد زندی که در شرایط تغذیه‌ای یکسان قرار داشتند در خارج تولید مثل انتخاب و برای همزمانسازی فحلی به مدت 12 روز سیدرگذاری شدند. سپس میش­ها به 5 گروه مساوی (100 راسی) تقسیم ‌شدند. به میش‌های گروه اول هورمونی تزریق نشد. به میش­های گروه دوم همزمان با برداشت سیدر 400 واحد eCG تزریق شد. به میش­های گروه سوم همزمان با برداشت سیدر 400 واحد eCG و یک میلیلیترPGF2α  تزریق شد. به میش­های گروه چهارم همزمان با برداشت سیدر مقدار400 واحد eCG و در روز چهاردهم یک میلیلیتر  GnRH تزریق شد. به میش­های گروه پنجم همزمان با برداشت سیدر مقدار400 واحد eCG، یک میلیلیترPGF2α  و در روز چهاردهم یک میلیلیتر GnRH تزریق شد. تمامی میش­ها 54 ساعت پس از سیدربرداری تلقیح مصنوعی شدند. نتایج نشان داد که درصد فحلی در تمامی گروههای دریافت کننده تیمارهای هورمونی از گروه کنترل بالاتر بوده است (05/0>P) ولی بین تیمارها اختلاف معنی­داری وجود نداشت (05/0P). همچنین درصد آبستنی، زایش و بره­زایی در گروههای دریافت کننده eCG و PGF2α نیز نسبت به گروه کنترل بالاتر بود (05/0>P). در نتیجه با استفاده از تزریق  eCG در هنگام سیدر برداری و GnRH در روز تلقیح مصنوعی میتوان بازده تولیدمثلی را در گوسفندان نژاد زندی در خارج فصل تولیدمثلی بهبود بخشید.

<p>Background: Accurate, non-invasive diagnosis of, and screening for, coronary artery disease (CAD) and restenosis after coronary revascularization has been a challenge due to either low sensitivity/specificity or relevant morbidity associated with current diagnostic modalities.</p> <p>Methods: To assess sensitivity and specificity of a new computerized, multiphase, resting electrocardiogram analysis device (MultiFunction-CardioGram^sm or MCG a.k.a. 3DMP) for the detection of relevant coronary stenosis (&#62;70%), a meta-analysis of three published prospective trials performed in the US on patient data collected using the US manufactured device and analyzed using the US-based software and New York data analysis center from patients in the US, Germany, and Asia was completed. A total of 1076 patients from the three trials (US - 136; Germany - 751; Asia - 189) (average age 62 &#177; 11.5, 65 for women, 60 for men) scheduled for coronary angiography, were included in the analysis. Patients enrolled in the trials may or may not have had prior angiography and/or coronary intervention. Angiographic results in all studies were classified for hemodynamically relevant stenosis (&#62; 70%) by two US based angiographers independently.</p> <p>Results: Hemodynamically relevant stenosis was diagnosed in 467 patients (43.4%). The device, after performing a frequency-domain, computational analysis of the resting ECG leads and computer-database comparison, calculated a coronary ischemia &#8220;severity&#8221; score from 0 to 20 for each patient. The severity score was significantly higher for patients with relevant coronary stenosis (5.4 &#177; 1.8 vs. 1.7 &#177; 2.1). The study device (using a cut-off score for relevant stenosis of 4.0) correctly classified 941 of the 1076 patients with or without relevant stenosis (sensitivity-91.2%; specificity-84.6%; NPV 0.942, PPV 0.777). Adjusted positive and negative predictive values (PPV and NPV) were 81.9% and 92.6%, respectively (ROC AUC = 0.881 [95% CI: 0.860-0.903]). Subgroup analysis showed no significant influence of sex, age, race/nationality, previous revascularization procedures, resting ECG morphology, or participating center on the device's diagnostic performance.</p> <p>Conclusions: The new computerized, multiphase, resting ECG analysis device (MultiFunction-CardioGram^sm) has been shown in this meta-analysis to safely and accurately identify patients with relevant coronary stenosis (&#62;70%) with high sensitivity and specificity and high negative predictive value. Its potential use in the evaluation of symptomatic patients suspected to suffer from coronary disease/ischemia is discussed.</p>

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&lt;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&lt;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.

The electrocardiogram (ECG) is essential for the diagnosis of some potentially life-threatening and time sensitive conditions, such as ST-elevation in myocardial infarction (MI). It is therefore imperative that healthcare professionals responsible for performing and interpreting ECGs are alert to the features of lead misplacement, as these can alter the ECG appearance dramatically, resulting in unnecessary investigations, admission to hospital, and treatment. ECG lead misplacement can result in significant harm to the patient if essential treatment is withheld or if the incorrect treatment is delivered solely on the basis of ECG findings. Case report: An unusual and previously unreported case of misplacement of all 12 ECG leads is presented, which would have resulted in significant harm to the patient had it not been identified so early. Conclusion: The ECG is one of the most important and most frequently requested investigations in the management of the acutely ill patient. A review of ECG lead misplacement is presented.

Abstract Classifying arrhythmias can be a tough task for a human being and automating this task is highly desirable. Nevertheless fully automatic arrhythmia classification through Electrocardiogram (ECG) signals is a challenging task when the inter-patient paradigm is considered. For the inter-patient paradigm, classifiers are evaluated on signals of unknown subjects, resembling the real world scenario. In this work, we explore a novel ECG representation based on vectorcardiogram (VCG), called temporal vectorcardiogram (TVCG), along with a complex network for feature extraction. We also fine-tune the SVM classifier and perform feature selection with a particle swarm optimization (PSO) algorithm. Results for the inter-patient paradigm show that the proposed method achieves the results comparable to state-of-the-art in MIT-BIH database (53% of Positive predictive (+P) for the Supraventricular ectopic beat (S) class and 87.3% of Sensitivity (Se) for the Ventricular ectopic beat (V) class) that TVCG is a richer representation of the heartbeat and that it could be useful for problems involving the cardiac signal and pattern recognition.

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.<br />

Telemedicine is always a popular topic thanks to the constants advancements of technology. The focus on development of new devices has been mainly on decreasing size to increase portability. Our research focused on improving functionality but not giving up on portability and cost. In this paper we are presenting the first prototype device that measures 4-leads electrocardiogram (ECG) and phonocardiogram (PCG) signals with low cost, high portability and wireless connectivity features in mind. We designed and developed a prototype that measures ECG using a standard ECG cable; we designed and developed a digital stethoscope prototype and also the necessary hardware for both medical signals to be transmitted through Bluetooth to a computer. We present here the hardware design, a new communication protocol for transmission of both signals from the device to the computer, and the software system to enable remote consultations. We designed the prototype with the main purpose of using low cost parts without sacrificing functionality, with the purpose of using it in remote zones of the Caribbean coast of Colombia. We show open issues and prepare a field implementation of the kit in the target zone.

ECG is not taught to dental students formally in the dental curriculum. The general assumption is that dental surgeons do not handle any ECG related cases in clinical practice. But with an increase in medically compromised patients, the need for an interdisciplinary approach among dental and medical practitioners in the treatment of critically ill patients is becoming more relevant. Hence, we have to be aware of the basics of common medical investigations to be competent to assess and comprehend the medical conditions. So, this paper focuses on orienting the beginner to the basic concepts of ECG from the clinical perspective. The paper also discusses the ECG changes of myocardial infarction to familiarize the dental surgeon to read the ECG.

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.

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 &amp;plusmn; 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&amp;ndash;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 longer Tpeak&amp;ndash;Tend interval than in the control population.Keywords: J wave, ERP athletes, T wave

The aim of the present study was to compare heart rate variability (HRV) at rest and during exercise using a temporal series obtained with the Polar S810i monitor and a signal from a LYNX® signal conditioner (BIO EMG 1000 model) with a channel configured for the acquisition of ECG signals. Fifteen healthy subjects aged 20.9 ± 1.4 years were analyzed. The subjects remained at rest for 20 min and performed exercise for another 20 min with the workload selected to achieve 60% of submaximal heart rate. RR series were obtained for each individual with a Polar S810i instrument and with an ECG analyzed with a biological signal conditioner. The HRV indices (rMSSD, pNN50, LFnu, HFnu, and LF/HF) were calculated after signal processing and analysis. The unpaired Student t-test and intraclass correlation coefficient were used for data analysis. No statistically significant differences were observed when comparing the values analyzed by means of the two devices for HRV at rest and during exercise. The intraclass correlation coefficient demonstrated satisfactory correlation between the values obtained by the devices at rest (pNN50 = 0.994; rMSSD = 0.995; LFnu = 0.978; HFnu = 0.978; LF/HF = 0.982) and during exercise (pNN50 = 0.869; rMSSD = 0.929; LFnu = 0.973; HFnu = 0.973; LF/HF = 0.942). The calculation of HRV values by means of temporal series obtained from the Polar S810i instrument appears to be as reliable as those obtained by processing the ECG signal captured with a signal conditioner.

The original version of the most successful approach for power-line (PL) interference removal from ECG, called subtraction procedure, is based on linear segment detection in the signal and hardware synchronised analogue-to-digital conversion to cope with the PL frequency variations. However, this is not feasible for battery supplied devices and some computer-aided ECG systems. Recent improvements of the procedure apply software measurement of the frequency variations that allow a re-sampling of the contaminated signal with the rated PL frequency followed by interference removal and back re-sampling for restoration of the original time intervals. This study deals with a more accurate software frequency measurement and introduces a notch filtration as alternative to the procedure when no linear segments are encountered for long time, e.g. in cases of ventricular fibrillation or tachycardia. The result obtained with large PL frequency variations demonstrate very small errors, usually in the range of ± 20 μV for the subtraction procedure and ± 60 μV for the notch filtration, the last values strongly depending on the frequency contents of the QRS complexes.

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.

Work is devoted to research dynamics of parameters of high resolution ECG (HRECG) and heart rate variability (HVR) methods in patients with acute coronary syndrome in determining myocardial electrical instability and disease trend the carried out. The researches have shown that, the HRECG and HRV variables in acute coronary syndrome, patients have various possible changes, which correlate with the severity of the current disease.

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 investigações adicionais baseado nos achados do ECG de 12 derivações deve ser criterioso.

Among many of the electrode designs used in electrocardiography (ECG), concentric ring electrodes (CREs) are one of the most promising due to their enhanced spatial resolution. Their development has undergone a great push due to their use in recent years; however, they are not yet widely used in clinical practice. CRE implementation in textiles will lead to a low cost, flexible, comfortable, and robust electrode capable of detecting high spatial resolution ECG signals. A textile CRE set has been designed and developed using screen-printing technology. This is a mature technology in the textile industry and, therefore, does not require heavy investments. Inks employed as conductive elements have been silver and a conducting polymer (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate; PEDOT:PSS). Conducting polymers have biocompatibility advantages, they can be used with flexible substrates, and they are available for several printing technologies. CREs implemented with both inks have been compared by analyzing their electric features and their performance in detecting ECG signals. The results reveal that silver CREs present a higher average thickness and slightly lower skin-electrode impedance than PEDOT:PSS CREs. As for ECG recordings with subjects at rest, both CREs allowed the uptake of bipolar concentric ECG signals (BC-ECG) with signal-to-noise ratios similar to that of conventional ECG recordings. Regarding the saturation and alterations of ECGs captured with textile CREs caused by intentional subject movements, silver CREs presented a more stable response (fewer saturations and alterations) than those of PEDOT:PSS. Moreover, BC-ECG signals provided higher spatial resolution compared to conventional ECG. This improved spatial resolution was manifested in the identification of P1 and P2 waves of atrial activity in most of the BC-ECG signals. It can be concluded that textile silver CREs are more suitable than those of PEDOT:PSS for obtaining BC-ECG records. These developed textile electrodes bring the use of CREs closer to the clinical environment.

This paper describes a solution for mobile heart monitoring. In part of hardware the authors focused on engineering problems of increasing the number of ECG leads and increasing the sampling rate. It potentially allows to increase the effectiveness and accuracy of localization and to decrease the influence of pacemaker pulses on the ECG signal recording respectively. Implementation of hardware and software parts is described. The method and software tool for wavelet-based analysis of ECG signals are proposed for arrhythmia detection task. Experimental results show that proposed wavelet-based method of ECG analysis can detect signs of arrhythmia. Results of wireless channel speed test confirm that the chosen hardware meets the requirements of wireless protocol bandwidth. Proposed solutions are suitable for portable heart monitoring systems.

<span>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.</span>

This paper proposes a hybrid model to classify cardiac arrhythmias and select their features in an optimal way. In the proposed model, the Genetic Algorithm was used to optimally select the features, and the Decision Tree with the C4.5 algorithm was applied to the extracted features to classify and train the model. The proposed approach was used to classify data into normal and abnormal classes as well as a 16-class collection of arrhythmias. To evaluate the performance of the proposed model compared with similar methods, we used the UCI arrhythmia dataset along with accuracy, sensitivity, specificity, and average Sen-Spec metrics. The efficiency of the proposed method in both two-class and 16-class modes significantly improved the accuracy, sensitivity, the average of sensitivity and specificity parameters compared to similar methods. Our approach obtained values of 86.96%, 88.88%, and 86.55% for the two-class mode and 78.76%, 76.36%, and 78.69% for the 16-class mode classification in terms of accuracy, sensitivity, and the average Sen-Spec metrics respectively. The above-mentioned values are reported as the highest for the UCI arrhythmia dataset. Keywords: Classification, Feature selection, ECG, Arrhythmia, Decision tree, Genetic algorithm

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.

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 experience suggests that more focused teaching of conduction abnormalities and posterior infarctions may be beneficial. The CORD database should be considered for incorporation into an ECG curriculum during residency training.

Here, we propose a signal processing based approach for the extraction of the fetal heart rate (FHR) from Maternal Abdominal ECG (MAECG) in a non-invasive way. Datasets from a Physionet database has been used in this study for evaluating the performance of the proposed model that performs three major tasks; preprocessing of the MAECG signal, separation of Fetal QRS complexes from that of maternal and estimation of Fetal R peak positions. The MAECG signal is first preprocessed with improved multistep filtering techniques to detect the Maternal QRS (MQRS) complexes, which are dominant in the MAECG. A reference template is then reconstructed based on MQRS locations and removed from the preprocessed signal resulting in the raw FECG. This extracted FECG is further corrected and enhanced before obtaining the Fetal R peaks. The detection of FQRS and calculation of FHR has been compared against the reference Fetal Scalp ECG. Results indicate that the approach achieved good accuracy.

<p>Abstract</p> <p>Background</p> <p>Detection of characteristic waves, such as QRS complex, P wave and T wave, is one of the essential tasks in the cardiovascular arrhythmia recognition from Electrocardiogram (ECG).</p> <p>Methods</p> <p>A multiscale morphological derivative (MMD) transform-based singularity detector, is developed for the detection of fiducial points in ECG signal, where these points are related to the characteristic waves such as the QRS complex, P wave and T wave. The MMD detector is constructed by substituting the conventional derivative with a multiscale morphological derivative.</p> <p>Results</p> <p>We demonstrated through experiments that the Q wave, R peak, S wave, the onsets and offsets of the P wave and T wave could be reliably detected in the multiscale space by the MMD detector. Compared with the results obtained via with wavelet transform-based and adaptive thresholding-based techniques, an overall better performance by the MMD method was observed.</p> <p>Conclusion</p> <p>The developed MMD method exhibits good potentials for automated ECG signal analysis and cardiovascular arrhythmia recognition.</p>

El análisis multiescala es un área de gran actividad investigativa con fuerte impacto en computación científica y matemática aplicada, ocupando un lugar de privilegio en la forma como se entiende la relación entre la matemática y las demás ciencias. Aunque el estudio matemático de problemas multiescala está bastante documentado, estas técnicas heredan en el entorno discreto la naturaleza mal condicionada del problema. La molificación discreta ha sido empleada con éxito en la solución numérica de diversos problemas mal condicionados. Este árticulo propone una nueva técnica de análisis multiescala, basada en molificación discreta. El procedimiento aquí propuesto usa resultados de algebra lineal numérica para implementar molificación discreta en el algoritmo de Mallat. La nueva técnica tiene una teoría simple, una implementación eficiente y proporciona resultados de calidad comparable a técnicas multiescala clásicas tipo onditas (wavelet). El proceso es aplicado en señales electrocardiográficas contaminadas con ruido no blanco, para fines de comparación.

Introduction: Ambulatory unit of City Institute for Urgent Medical Care Belgrade (CIFUMCB) is a part of the primary healthcare system, and as such it is equipped with standardized diagnostic tools, electrocardiograph (ECG) being one of them. The diagnostic method of electrocardiography is performed on a daily basis in order to differentiate a variety of symptoms. Since the majority of patients coming to the ambulatory unit of CIFUMCB for help are first time visitors, unfamiliar to the physician who usually has no insight at all at their previous medical documentation, it is clear how this simple diagnostic tool becomes useful in revealing the underlying cause of a certain health issue. Aim: to present all kinds of patients’ complaints that required ECG diagnostic in the Ambulatory unit of CIFUMCB. Methodology: The electronic database of the Ambulatory Unit of CIFUMCB was utilized from January 1-22, 2015 on 206 examined patients. Health problems of the patients who had undergone ECG diagnosis were analyzed. A single patient could have had more than one health problem, in addition to the one of interest. Results: Among 206 examined patients nearly 50% had undergone ECG diagnostic. The reasons for performing ECG recording were: high blood pressure, chest pain and other difficulties such as shortness of breath, cough, rapid heartbeat, headache and dizziness, numbness in arms, nausea, and fever. Upon comparison of various health problems from different groups, usually from cardiovascular, respiratory and central nervous system origin, there was no statistically significant difference. Conclusion: The most common indications for ECG diagnostic among our patients were high blood pressure, followed by chest pain, irregular and rapid heartbeat, headaches and dizziness. Only 10% of these patients were referred to specialist for further assessment and treatment.

IoT enabled smart car era is expected to begin in the near future as convergence between car and IT accelerates. Current smart cars can provide various information and services needed by the occupants via wearable devices or Vehicle to Everything (V2X) communication environment. In order to provide such services, a system to analyze wearable device information on the smart car platform needs to be designed. In this paper a real time user recognition method using 2D ECG (Electrocardiogram) images, a biometric signal that can be obtained from wearable devices, will be studied. ECG (Electrocardiogram) signal can be classified by fiducial point method using feature points detection or nonfiducial point method due to time change. In the proposed algorithm, a CNN based ensemble network was designed to improve performance by overcoming problems like overfitting which occur in a single network. Test results show that 2D ECG image based user recognition accuracy improved by 1%~1.7% for the fiducial point method and by 0.9%~2% for the nonfiducial point method. By showing 13% higher performance compared to the single network in which recognition rate reduction occurs because similar characteristics are shown between classes, capability for use in a smart vehicle platform based user recognition system that requires reliability was demonstrated by the proposed method.

BACKGROUND:This study investigated the feasibility of using the precordial surface ECG lead interlead QRS dispersion (IQRSD) in the identification of abnormal ventricular substrate in arrhythmogenic right ventricular cardiomyopathy (ARVC). METHODS:Seventy-one consecutive patients were enrolled and reclassified into 4 groups: definite ARVC with epicardial ablation (Group 1), ARVC with ventricular tachycardia (VT, Group 2), idiopathic right ventricular outflow tract VT without ARVC (Group 3), and controls without VT (Group 4). IQRSD was quantified by the angular difference between the reconstruction vectors obtained from the QRS-loop decomposition, based on a principal component analysis (PCA). Electroanatomic mapping and simulated ECGs were used to investigate the relationship between QRS dispersion and abnormal substrate. RESULTS:The percentage of the QRS loop area in the Group 1-2 was smaller than the controls (P = 0.01). The IQRSD between V1-V2 could differentiate all VTs from control (P<0.01). Group 1-2 had a greater IQRSD than the Group 3-4 (V4-V5,P = 0.001), and Group 1 had a greater IQRSD than Group 3-4 (V6-Lead I, P<0.001). Both real and simulated data had a positive correlation between the maximal IQRSD (γ = 0.62) and the extent of corresponding abnormal substrate (γ = 0.71, both P<0.001). CONCLUSIONS:The IQRSD of the surface ECG precordial leads successfully differentiated ARVC from controls, and could be used as a noninvasive marker to identify the abnormal substrate and the status of ARVC patients who can benefit from epicardial ablation.

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

The aim of this study was to compare two protocols ofestrus synchronization in Santa Inês ewes. Thirty-eight ewes wererandomly divided into two groups of estrus synchronization: protocolPGF2α (two doses of 0.530 mg of PGF2α, nine days apart)and protocol MAP+eCG (intravaginal sponge impregnated withmedroxyprogesterone acetate, for 12 days, and then an injectionof 250 IU of eCG). The experiment was in a cross-over design,two estrous cycles apart. On the final day of protocol, a transrectalultrasound examination was carried out to measure the size of thelargest and second largest ovarian follicles and on day 7 of estrouscycle blood was collected to measure serum P4 concentration.Laparoscopy was carried out on day 11 after the end of protocols to count corpora lutea. Synchronization rate, size of largest andsecond largest ovarian follicles, interval between the end of theprotocol to estrus and ovulation rate did not differ between protocols.Ewes synchronized with MAP+eCG had greater serumP4 concentrations than ewes synchronized with PGF2α (3.9 and2.8 ng/mL, respectively, P<0.05). Based on the results, it may beconcluded that, although the protocol MAP+eCG was superior ininducing higher serum concentration of P4, the protocol PGF2αwas equivalent regarding estrus synchronization.

<p><i>Background</i>: Resting electrocardiogram (ECG) shows limited sensitivity and specificity for the detection of coronary artery disease (CAD), where patients with a history of coronary revascularization may pose special challenges. Several methods exist to enhance sensitivity and specificity of resting ECG for diagnosis of CAD, but such methods are not better than a specialist's judgement. We compared a new computer-enhanced, resting ECG analysis device, 3DMP, to coronary angiography to evaluate the device's accuracy in detecting hemodynamically relevant CAD.</p> <p><i>Methods</i>: A convenience sample of 172 patients with a history of coronary revascularization scheduled for coronary angiography was evaluated with 3DMP before coronary angiography. 3DMP's sensitivity and specificity in detecting hemodynamically relevant coronary stenosis as diagnosed with coronary angiography were calculated as well as odds ratios for the 3DMP severity score and coronary artery disease risk factors.</p> <p><i>Results</i>: The 3DMP system accurately identified 50 of 55 patients as having hemodynamically relevant stenosis (sensitivity 90.9%, specificity 88.0%). Positive and negative predictive values for the identification of coronary stenosis as diagnosed in coronary angiograms were 62.7% and 97.8% respectively. Risk and demographic factors in a logistic regression model had a markedly lower predictive power for the presence of coronary stenosis in these patients than did 3DMP severity score (odds ratio 2.04 [0.74-5.62] vs. 73.57 [25.10-215.68]). A logistic regression combining severity score with risk and demographic factors did not add significantly to the prediction quality (odds ratio 80.00 [27.03-236.79]).</p> <p><i>Conclusions</i>: 3DMP's computer-based, mathematically derived analysis of resting two-lead ECG data provides detection of hemodynamically relevant CAD in patients with a history of coronary revascularization with high sensitivity and specificity that appears to be at least as good as those reported for other resting and/or stress ECG methods currently used in clinical practice.</p>

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.

Background: Significance of an ST-T abnormality in subjects with no apparent heart diseases is to be determined. Subjects and methods: The study involved 44,990 adults (16,368 males and 28,622 females) aged 40-85 years who under went an annual health examination. Cardiovascular risks (CVRs) were considered positive if 1) body mass index was ≥ 25Kg/m2, 2) systolic blood pressure (BP) ≥ 130 mmHg and/or diastolic BP ≥ 85mmHg, 3) triglyceride ≥ 150 mg/ dl, 4) HDL-C level ≤ 40mg/dl for men and ≤ 50mg/dl for women, or 5) fasting blood glucose ≤ 110 mg/dl. The relation between CVRs and ST-T abnormalities were evaluated. Results: ST-T abnormalities were found in 6.49% in males, and more frequently in females: 8.45%. Each CVR and the number of combined CVRs were risk factors for ST-T abnormalities on ECG (P < 0.0001 for a trend). On the other hand, ECG-based LVH was found in 5.7% but showed no relation with CVRs or their com binations. ST-T abnormalities may represent preclinical cardiac involvement of CVRs more sensitively than LVH on ECG and ECG findings may be used in mass examinations. Conclusions: ST-T abnormalities without apparent heart diseas may be considered to be nonspecific but this cross-sectional study showed that they are related to CVRs and may be used as an early marker of preclinical cardiac damage by CVRs.

Acute pulmonary embolism is a devastating disease that often leads to mortality . Previous investigators have found that thrombolysis reduces mortality in men but not significantly in women with pulmonary embolism. Many of the previous studies are with tenecteplase and alteplase. Here, we describe intra - venous thrombolysis with streptokinase in seven patients with pulmonary embolism who survived including two women. Further, we have one patient who had a new onset of S wave in lead I which subsequently disappeared after embolectomy. We also comment on the usefulness of shock sign in 2 deciding on thrombolysis .We propose a new sign for noninvasive assessment of need for thrombolysis in pulmonary embolism. New onset S wave in Lead I in pulmonary embolism can be used as a new sign for deciding the need for thrombolysis. When added to the shock sign it can be used in the emergency deparment to decide the need for thrombolysis. Further, there are no clear end points as to when to stop thrombolysis. In all 4 patients we switched to heparin when spontaneous bleeding or oozing started. In all 4 patients subsequent CT scans showed that the patient has mild to moderate resolution of the pulmonary embolism and patients remained stable and have been discharged and are under regular follow up. Hence we propose that bleeding can be used as an end point for thrombolysis in acute pulmonary embolism. We also describe a patient who had new onset S wave that disappeared after successful pulmonary embolectomy. Probably, the S wave is a marker of main pulmonary artery branch occlusions.

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

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.

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).

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.

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%. Santrauka  Širdies ritmas yra vienas svarbiausių ir daugiausia informacijos apie pacientų būklę teikiančių fiziologinių parametrų. Širdies ritmas nustatomas iš elektrokardiogramos (EKG), atliekant QRS regionų, kurie yra interpretuojami kaip širdies dūžio ãtskaitos, paiešką. QRS regionų aptikimas yra klasikinis uždavinys, nagrinėjamas jau keletą dešimtmečių, todėl širdies dūžių nustatymo iš EKG signalų metodų yra labai daug. Deja, šie metodai tikslūs ir patikimi tik esant dideliam signalo ir triukšmo santykiui. Kai EKG signalai labai iškraipomi, QRS aptiktuvai ne visada gali atskirti QRS regioną, o kartais jį randa ten, kur iš tikro jo būti neturėtų. Straipsnyje siūlomas algoritmas, kurį taikant sumažinama triukšmo įtaka nustatant iš EKG signalų QRS regionus. Tam naudojamas QRS aptiktuvas, kartu prognozuojantis širdies dūžio atskaitą. Remiamasi arterinio kraujo spaudimo signalo duomenimis, renkama atskaitų statistika ir atliekama jos analizė. Raktiniai žodžiai: elektrokardiograma, arterinis kraujo spaudimas, širdies ritmas, QRS regionai, širdies dūžis.

BACKGROUND & OBJECTIVES The Electrocardiogram remains a crucial tool in the identification and management of acute myocardial infarction. A detailed analysis of patterns of ST-segment elevation may influence decisions regarding the perfusion therapy. This study was undertaken to identify the culprit vessel from ECG in patients with acute ST elevation myocardial infarction and correlate with coronary angiogram. MATERIALS & METHODS This is a prospective study, conducted on 126 patients in Osmania General Hospital, Hyderabad. Patients with ST segment elevation from ECG was evaluated to identify culprit vessel and later correlated with coronary angiogram. RESULTS Amongst 126 patients in this study, 70 patients had anterior wall and 56 patients had inferior wall myocardial infarction. ST> 1mm in V4R, ST  V3/ST  LIII <0.5 were equally sensitive in proximal RCA occlusion. While in patients with distal RCA occlusion the ratio of ST depression in Lead V3/ST elevation in Lead III between 0.5-1.2 had maximum sensitivity. In LCx occlusion ST elevation in Lead lll> Lead II was the most sensitive and ratio of STV3/STLIII >1.2 was the most specific criteria. ST in inferior leads > 1mm had maximum sensitivity in localizing occlusion in proximal D1 occlusion proximal to S1 as well. Absence of ST i in inferior leads is the most sensitive criteria in occlusion distal to S1 as well as in distal D1 in AWMI. CONCLUSION The admission ECG in patients with ST elevation AMI is valuable not only for determining early reperfusion treatment, but also provides important information to guide clinical decision-making.

Background In this study we assessed the relationship between corrected-QT intervals and other ECG characteristics with methadone dose and other parameters in MMT patients and healthy subjects. Methods This was a case-control study which was carried out on patients underwent MMT and healthy control group who had been referred to Ebne-Sina academic hospital, Mashhad during 2014 - 2015. At the time of the study, 40 patients who received MMT therapy for at least 6 months and 40 voluntary healthy subjects who matched on age and sex enrolled in the study. 12-lead ECG was performed for all the patients. Mean QT interval, PR interval and QRS duration in every 12 leads were documented for each patient in maximum. Results To evaluate the patients, we divided 80 patients into two groups: 40 patients under treatment with Methadone and 40 voluntary participants as control group. There were 20 males and 20 females in each group. Duration of addiction was 214.80 ± 126.99 months in MMT group. Significant differences were observed in PRi between the patient and control groups (P = 0.007), and also between methadone dose and PRi (r = 0.468, P = 0.038) in males. QTc prolongation was reported in 4 patients of addicted group (10%). All of the QTc prolongation patients were female (P = 0.037). There was significant relationship between PRi and weight (P = 0.015), addiction period (P = 0.011), methadone treatment period (P = 0.018) as well as methadone dosage (P = 0.14). Methadone cut off point of 65 mg had a significant relationship with systolic blood pressure (P = 0.002), diastolic blood pressure (P = 0.013), QTCi (P = 0.016) and QRS (P = 0.044); however, no significant relationship was reported with PRi (P = 0.451). Conclusions We found that there is no exact dosage of methadone in which the side effects such as TdP (Torsade de pointes) or QTc prolongation can be predicted. Female gender and methadone dosage ≥ 65 mg were risk factors of our study for QTc prolongation which may result in subsequent deteriorated conditions.

Strong correlation between characteristic features of norms ECG intervals and age and gender of children has been established due to the process of growth and development. These findings should be regarded in functional identification of heart conduction disorders. The ECG waves and intervals become stable at an age of 13–14 years due to the maturity of heart conduction system.Key words: cardio-vascular system, functional diagnostics, ECG time intervals, growth and development.

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.

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.

Compressed sensing (CS) is a promising approach to the compression and reconstruction of electrocardiogram (ECG) signals. It has been shown that following reconstruction, most of the changes between the original and reconstructed signals are distributed in the Q, R, and S waves (QRS) region. Furthermore, any increase in the compression ratio tends to increase the magnitude of the change. This paper presents a novel approach integrating the near-precise compressed (NPC) and CS algorithms. The simulation results presented notable improvements in signal-to-noise ratio (SNR) and compression ratio (CR). The efficacy of this approach was verified by fabricating a highly efficient low-cost chip using the Taiwan Semiconductor Manufacturing Company’s (TSMC) 0.18-μm Complementary Metal-Oxide-Semiconductor (CMOS) technology. The proposed core has an operating frequency of 60 MHz and gate counts of 2.69 K.

The concealed phase of arrhythmogenic right ventricular cardiomyopathy (ARVC) may initially manifest electrophysiologically. No studies have examined dynamic conduction/repolarization kinetics to distinguish benign right ventricular outflow tract ectopy (RVOT ectopy) from ARVC's early phase. We investigated dynamic endocardial electrophysiological changes that differentiate early ARVC disease expression from RVOT ectopy.22 ARVC (12 definite based upon family history and mutation carrier status, 10 probable) patients without right ventricular structural anomalies underwent high-density non-contact mapping of the right ventricle. These were compared to data from 14 RVOT ectopy and 12 patients with supraventricular tachycardias and normal hearts. Endocardial & surface ECG conduction and repolarization parameters were assessed during a standard S1-S2 restitution protocol.Definite ARVC without RV structural disease could not be clearly distinguished from RVOT ectopy during sinus rhythm or during steady state pacing. Delay in Activation Times at coupling intervals just above the ventricular effective refractory period (VERP) increased in definite ARVC (43 ± 20 ms) more than RVOT ectopy patients (36 ± 14 ms, p = 0.03) or Normals (25 ± 16 ms, p = 0.008) and a progressive separation of the repolarisation time curves between groups existed. Repolarization time increases in the RVOT were also greatest in ARVC (definite ARVC: 18 ± 20 ms; RVOT ectopy: 5 ± 14, Normal: 1 ± 18, p<0.05). Surface ECG correlates of these intracardiac measurements demonstrated an increase of greater than 48 ms in stimulus to surface ECG J-point pre-ERP versus steady state, with an 88% specificity and 68% sensitivity in distinguishing definite ARVC from the other groups. This technique could not distinguish patients with genetic predisposition to ARVC only (probable ARVC) from controls.Significant changes in dynamic conduction and repolarization are apparent in early ARVC before detectable RV structural abnormalities, and were present to a lesser degree in probable ARVC patients. Investigation of dynamic electrophysiological parameters may be useful to identify concealed ARVC in patients without disease pedigrees by using endocardial electrogram or paced ECG parameters.

Work is devoted to research dynamics of parameters of high resolution ECG (HRECG) and heart rate variability (HVR) methods in patients with acute coronary syndrome in determining myocardial electrical instability and disease trend the carried out. The researches have shown that, the HRECG and HRV variables in acute coronary syndrome, patients have various possible changes, which correlate with the severity of the current disease.

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.

The most common way to analyse heart rhythm is to calculate the RR-interval and the heart rate variability. For further evaluation, descriptive statistics are often used. Here we introduce a new and more natural heart rhythm analysis tool that is based on circular statistics and vector strength. Vector strength is a tool to measure the periodicity or lack of periodicity of a signal. We divide the signal into non-overlapping window segments and project the detected R-waves around the unit circle using the complex exponential function and the median RR-interval. In addition, we calculate the vector strength and apply circular statistics as wells as an angular histogram on the R-wave vectors. This approach enables an intuitive visualization and analysis of rhythmicity. Our results show that ECG-waves and rhythms can be easily visualized, analysed and classified by circular statistics and vector strength.

We proposed new electrodes that are applicable for electrocardiogram (ECG) monitoring under freshwater- and saltwater-immersion conditions. Our proposed electrodes are made of graphite pencil lead (GPL), a general-purpose writing pencil. We have fabricated two types of electrode: a pencil lead solid type (PLS) electrode and a pencil lead powder type (PLP) electrode. In order to assess the qualities of the PLS and PLP electrodes, we compared their performance with that of a commercial Ag/AgCl electrode, under a total of seven different conditions: dry, freshwater immersion with/without movement, post-freshwater wet condition, saltwater immersion with/without movement, and post-saltwater wet condition. In both dry and post-freshwater wet conditions, all ECG-recorded PQRST waves were clearly discernible, with all types of electrodes, Ag/AgCl, PLS, and PLP. On the other hand, under the freshwater- and saltwater-immersion conditions with/without movement, as well as post-saltwater wet conditions, we found that the proposed PLS and PLP electrodes provided better ECG waveform quality, with significant statistical differences compared with the quality provided by Ag/AgCl electrodes.

Objectives. To determine the ECG changes in a group of outpatients on chronic psychotropic medication, and the association, if any, with factors such as gender, age, co- morbid illness and the use of concomitant medication. Methods. Study subjects included patients 18 years and older attending the outpatient departments of Chris Hani Baragwanath and Johannesburg hospitals. The subjects’ demographic and clinical characteristics were obtained and a resting ECG was recorded. Results. Eighty patients were included in the study. The mean age of the subjects was 45.4 (standard deviation (SD) =18.2) years, with a minimum age of 18 and a maximum of 86 years. Fifty-four subjects (67.5%) had evidence of some ECG abnormalities. There was no significant difference between the occurrence of ECG abnormalities and the different age groups (p > 0.05), gender (p > 0.05), and different race groups (p > 0.05). Sixty-one subjects (76.3%) had no co-morbid medical illness and were on psychotropic medication only; of these patients 43 (70.5%) had abnormal ECG tracings (p > 0.05). The ECG abnormalities recorded included abnormal rate (28.8%), abnormal ST segment (20.5%), abnormal QRS complex (17.8%), abnormal T wave (15.4%), prolonged or borderline corrected QT interval (8.2%), irregular rhythm (5.5%) and prolonged PR interval (2.7%). There was a significant positive correlation between the corrected QT interval and age (r = 0.43, p < 0.05) and between corrected QT interval and female gender (r = 0.31, p < 0.05). There was no correlation between corrected QT interval and treatment of a co-morbid illness (r = 0.13, p > 0.05). Conclusion. The use of psychotropic drugs is associated with ECG changes in ordinary doses. However, this study serves to strengthen previous evidence that, although common, most of these changes are of a benign nature.

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.

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.

The aims of this study were to improve the cost-benefit ratio of the application of artificial insemination in fixed time (TAI) by the transcervical route in sheep, to test the dosage reduction and the use of the vulvar submucosa (VSM) route as an alternative for the application of equine chorionic gonadotropin (eCG) on the efficiency of the synchronization protocol and fertility to artificial insemination (AI) and to measure the level of cortisol in ewes as a result the application of this biotechnique. Blood samples were collected before AI, immediately after AI and seven days after AI. Six groups of twenty animals were used, and each group received doses of 200, 300 and 400 IU of eCG by the intramuscular route (IM) and VSM. Estrus was detected, and 48 hours later, the inseminations were performed by the transcervical route. Among the 120 treated ewes, 87.5% came in estrus. The percentage of the intrauterine deposition of semen was 88.3%. The pregnancy rate ranged from 20 to 70% between treatments, with an average of 46.66%. The VSM route was viable for the application of eCG in doses of 300 and 400 IU. The reduction in the eCG dose to 200 IU by the IM route reduces costs while maintaining the efficiency of estrus synchronization protocols and TAI with frozen semen in Santa Ines ewes. The average levels of cortisol were significant, at 1.15, 2.86 and 0.52 ?g/dL according to the three collections, being higher after the animal was off the easel at the end of AI. The procedures for performing the transcervical AI technique indicate that stress in the animals produces satisfactory fertility results and a low cost in multiparous ewes of the Santa Ines breed.

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.

Background: Paroxysmal atrioventricular block (P-AVB) is a well-known cause of syncope; however, its underlying mechanism is difficult to determine. This study aimed to evaluate a new ECG index, the “vagal score (VS),” to determine the mechanism of P-AVB. Methods: We evaluated the VS in 20 patients with P-AVB (13 men, 7 women; aged 25–78 years [mean, 59.3 years]). The VS was developed by assigning 1 point each for the following: (1) no AVB or intraventricular conduction disturbance on the baseline ECG, (2) PR prolongation immediately before P-AVB, (3) sinus slowing immediately before P-AVB, (4) initiation of P-AVB by PP prolongation, (5) sinus slowing during ventricular asystole, and (6) resumption of AV conduction with PP shortening, and by assigning –1 point each for (7) the initiation of P-AVB by a premature beat, and (8) resumption of AV conduction by an escape beat. Based on the clinical situations and electrophysiologic findings, we considered the mechanism of P-AVB as vagally mediated or intrinsic conduction disease (ICD). Results: The VS ranged from 5 to –2 points for each patient. Five patients with a definite vagally mediated P-AVB had high VSs (3–5 points). We observed characteristic ECG findings of ICD consisting of changes in AV conduction by an extrasystole and/or escape beat in only 5 of the 6 patients (83%) with a low VS (1 to –2). Conclusions: The VS is simple and potentially useful for determining the mechanism of P-AVB. P-AVB with a VS ≥3 strongly suggested a vagally mediated mechanism.

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.

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.

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.

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%.

Background: One of the main problems especially in operating room and monitoring devices is measurement of Blood Pressure (BP) by sphygmomanometer cuff. Objective: In this study we designed a new method to measure BP changes continuously for detecting information between cuff inflation times by using vital signals in monitoring devices. This will be achieved by extraction of the time difference between each cardiac cycle and a relative pulse wave. Methods: Finger pulse and ECG signals in lead I were recorded by a monitoring device. The output of monitoring device was inserted in a computer by serial network communication. A software interface (Microsoft Visual C#.NET ) was used to display and process the signals in the computer. Time difference between each cardiac cycle and pulse signal was calculated throughout R wave detection in ECG and peak of pulse signal by the software. The relation between time difference in two waves and BP was determined then the coefficients of equation were obtained in different physical situations. The results of estimating BP were compared with the results of sphygmomanometer method and the error rate was calculated. Results: In this study, 25 subjects participated among them 15 were male and 10 were female. The results showed that BP was linearly related to time difference. Average of coefficient correlation was 0.9±0.03 for systolic and 0.82±0.04 for diastolic blood pressure. The highest error percentage was calculated 8% for male and 11% for female group. Significant difference was observed between the different physical situation and arm movement changes. The relationship between time difference and age was estimated in a linear relationship with a correlation coefficient of 0.76. Conclusion: By determining linear relation values with high accuracy, BP can be measured with insignificant error. Therefore it can be suggested as a new method to measure the blood pressure continuously.

Wearable sensors have great potential uses in personal health monitoring systems, in which textile-based electrodes are particularly useful because they are comfortable to wear and are skin and environmentally friendly. In this paper, a hybrid textile electrode for electrocardiogram (ECG) measurement and motion tracking was introduced. The hybrid textile electrode consists of two parts: A textile electrode for ECG monitoring, and a motion sensor for patient activity tracking. In designing the textile electrodes, their performance in ECG measurement was investigated. Two main influencing factors on the skin-electrode impedance of the electrodes were found: Textile material properties, and electrode sizes. The optimum textile electrode was silver plated, made of a high stitch density weft knitted conductive fabric and its size was 20 mm &times; 40 mm. A flexible motion sensor circuit was designed and integrated within the textile electrode. Systematic measurements were performed, and results have shown that the hybrid textile electrode is capable of recording ECG and motion signals synchronously, and is suitable for ambulatory ECG measurement and motion tracking applications.

Objectives: Intense exercise elevates all heart chambers&rsquo; dimensions, left ventricular mass (LV mass), and left ventricular mass index (LV mass index). The relationship between increased ventricular arrhythmias and sudden cardiac death with LV dilatation and elevated LV mass has been previously demonstrated. We investigated whether sports-related LV dilatation and elevated LV mass and LV mass index cause an increase in ventricular repolarization heterogeneity. Patients and Methods: This prospective observational study recruited 565 participants. There were 226 (female: 28) athletes and 339 (female: 45) healthy controls between 17 and 42 years of age. They were evaluated using 12-lead-electrocardiography and transthoracic echocardiography. Electrocardiograms were obtained at a rate of 50 mm/s and an amplitude of 10 mV, including at least 3 QRS complexes for each derivation. They were taken with 12 standard deviations. Transmural dispersion of repolarization indexes (TDR) (Tp-Te interval, Tp-Te/QT ratio and Tp-Te/QTc ratio, Tp-Te(d)) were measured from precordial derivations. Measurements weretakenwith a program which was generated with MATLAB codes. Results: Tp-Te interval, Tp-Te/QT ratio, Tp-Te/QTc ratio, Tp-Te(d), PW (posterior wall thickness), IVS (interventricular septal thickness), LVEDD (left ventricular end-diastolic diameter), LV mass (left ventricular mass), and LV mass index (left ventricular mass index) for the athlete group were significantly higher than for the control group. Correlation analyses revealed that TDR indexes significantly correlated with PW, IVS, LVEDD, LV mass, and LV mass index. Conclusion: LV mass and LV mass index increase in well-trained athletes, and this increase leads to an increase in TDR indexes. The increased frequency of ventricular arrhythmia and sudden cardiac death may be explained with increasing ventricular repolarization heterogeneity in these individuals.

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.

Electrocardiogram signal analysis is based on detecting a fiducial point consisting of the onset, offset, and peak of each waveform. The accurate diagnosis of arrhythmias depends on the accuracy of fiducial point detection. Detecting the onset and offset fiducial points is ambiguous because the feature values are similar to those of the surrounding sample. To improve the accuracy of this paper&#8217;s fiducial point detection, the signal is represented by a small number of vertices through a curvature-based vertex selection technique using polygonal approximation. The proposed method minimizes the number of candidate samples for fiducial point detection and emphasizes these sample&#8217;s feature values to enable reliable detection. It is also sensitive to the morphological changes of various QRS complexes by generating an accumulated signal of the amplitude change rate between vertices as an auxiliary signal. To verify the superiority of the proposed algorithm, error distribution is measured through comparison with the QT-DB annotation provided by Physionet. The mean and standard deviation of the onset and the offset were stable as <inline-formula> <math display="inline"> <semantics> <mrow> <mo>&#8722;</mo> <mn>4.02</mn> <mo>&#177;</mo> <mn>7.99</mn> </mrow> </semantics> </math> </inline-formula> ms and <inline-formula> <math display="inline"> <semantics> <mrow> <mo>&#8722;</mo> <mn>5.45</mn> <mo>&#177;</mo> <mn>8.04</mn> </mrow> </semantics> </math> </inline-formula> ms, respectively. The results show that proposed method using small number of vertices is acceptable in practical applications. We also confirmed that the proposed method is effective through the clustering of the QRS complex. Experiments on the arrhythmia data of MIT-BIH ADB confirmed reliable fiducial point detection results for various types of QRS complexes.