Design of a Programmable ECG Generator Using a Dynamical Model

This article is to design and develop a programming electrocardiogram (ECG) generator. It can be used to test the efficiency of algorithms and to calibration and maintenance of electrocardiograph equipment. We simplified and modified the three coupled ordinary differential equations of McSharry’s model to single differential equation to generate the synthetic ECG waveforms. This generator can provide the adjusted amplitude, heart rate, QRS-complex slopes, and P- and T-wave position parameters. The system can set the rage of the average gear rate from 20 to 120 beat per minute (BPM) with an adjustable variation of 1 BPM. The parameters of the adjusted synthetic ECG model can be stored in Flash memory of the system through Universal Serial Bus (USB) 2.0 interface. The results were generated four different ECG waveforms for test which are Lead I, Lead II, hyperkalaemia and left bundle branch block. According to the experimental results, the system can not only generate the ECG waveforms of the setting heart rate but also can adjust the different types of ECG waveforms. ECG generator will generate the synthetic electrocardiograms for testing the electrocardiogram analytic algorithms. ECG generator will generate the synthetic electrocardiograms for testing the electrocardiogram analytic algorithms.

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Characteristics of the reindeer electrocardiogram

Rangifer ◽

10.7557/2.2.2.412 ◽

1982 ◽

Vol 2 (2) ◽

pp. 36

Author(s):

Jouni Timisjärvi ◽

Mauri Nieminen ◽

Sven Nikander

Keyword(s):

Heart Rate ◽

Indirect Evidence ◽

Frontal Plane ◽

Heart Beat ◽

P Wave ◽

Qrs Complex ◽

Single Plane ◽

T Wave ◽

Wide Range ◽

Electrocardiogram Ecg

The electrocardiogram (ECG) provides reliable information about heart rate, initiation of heart beat and also, to some degree, indirect evidence on the functional state of the heart muscle. A wide range of such information is readily obtainable from conventional scalar leads, even if the records are limited to a single plane. The present investigation deals with the normal reindeer ECG in the frontal plane. The technique used is the scalar recording technique based on the Einthovenian postulates. The P wave was positive in leads II, III and aVF, negative in lead aVL and variable in leads I and aVR. The direction of the P vector was 60 to 120°. The QRS complex was variable. The most common forms of QRS complex were R and rS in leads I and aVR; R, Rs and rS in lead aVL and Qr or qR in other leads. The most common direction of the QRS vector was 240 to 300°. The T wave was variable. The duration of various intervals and deflection depended on heart rate.Elektrokardiogram på ren.Abstract in Swedish / Sammandrag: Elektrokardiogramet (EKG) ger tillförlitliga uppgifter om hjärtfrekvens, retledning och, indirekt, delvis även om hjärtmuskelns funktionell tillstånd. Största delen av denna information fås med normal skalar koppling även om registrering sker i ett plan. I detta arbete har renens normala EKG i frontalplanet undersökts. Kopplingarna har baserats på Einthovs postulat. P-vågen var riktad uppåt i koppling II, III och aVF, nedåt i koppling aVL och den varierade i koppling I och aVR. P-vektorns riktning var 60 - 120°. QRS-komplexet varierade. De vanligaste formerna var R och rS i koppling I och aVR; R, Rs och rS i koppling aVL och Qr eller qR i andra kopplingar. Vanligen var QRS-vektorns riktning 240 - 300°. T-vågen varierade. Awikelserna och intervallernas längd var beroende av hiärtfrekvenssen.Poron sydänsähkökäyrän ominaisuuksia.Abstract in Finnish / Yhteenveto: Sydänsähkökäyrästä saadaan luotettavaa tietoa sydämen syketiheydestä, sähköisestä johtumisesta ja välillisesti jossain määrin myös sydänlihaksen toiminnallisesta tilasta. Suurin osa tämänkaltaista tietoa voidaan saada tavanomaisia skalaarisia kytkentöjäkäyttäen, ja usein yhdessä tasossa tapahtuva rekisteröinti on riittävä. Tässä työssä on tutkittu porojen normaalia sydänsähkökäyrää ja sen eri poikkeamien suuntautumista frontaalitasossa, kun rekisteröinnissä on käytetty Einthovenin postulaattien mukaisia raajakytkentöjä. P aalto suuntautui ylöspäin kythkennöissä II, III ja aVF, alaspäin kytkennässä aVL ja vaihteli kytkennöissä I ja aVR. P vektorin suunta oli 60 - 120°. QRS kompleksi vaihteli. Tavallisimmat muodot olivat R ja rS kytkennöissä I ja aVR; R, Rs ja rS kytkennässä aVL ja Qr tai qR muissa kytkennöissä. Tavallisin QRS vektorin suunta oli 240 - 300°. T aalto vaihteli. Poikkeaminen ja intervallien kesto riippui sydämen syketiheydestä.

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ECG SIGNAL GENERATION AND HEART RATE VARIABILITY SIGNAL EXTRACTION: SIGNAL PROCESSING, FEATURES DETECTION, AND THEIR CORRELATION WITH CARDIAC DISEASES

Journal of Mechanics in Medicine and Biology ◽

10.1142/s021951941240012x ◽

2012 ◽

Vol 12 (04) ◽

pp. 1240012 ◽

Cited By ~ 4

Author(s):

GOUTHAM SWAPNA ◽

DHANJOO N. GHISTA ◽

ROSHAN JOY MARTIS ◽

ALVIN P. C. ANG ◽

SUBBHURAAM VINITHA SREE

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Sinus Bradycardia ◽

Premature Ventricular Contraction ◽

P Wave ◽

Ecg Signal ◽

Qrs Complex ◽

T Wave ◽

St Segment ◽

Cardiac Disorders

The sum total of millions of cardiac cell depolarization potentials can be represented by an electrocardiogram (ECG). Inspection of the P–QRS–T wave allows for the identification of the cardiac bioelectrical health and disorders of a subject. In order to extract the important features of the ECG signal, the detection of the P wave, QRS complex, and ST segment is essential. Therefore, abnormalities of these ECG parameters are associated with cardiac disorders. In this work, an introduction to the genesis of the ECG is given, followed by a depiction of some abnormal ECG patterns and rhythms (associated with P–QRS–T wave parameters), which have come to be empirically correlated with cardiac disorders (such as sinus bradycardia, premature ventricular contraction, bundle-branch block, atrial flutter, and atrial fibrillation). We employed algorithms for ECG pattern analysis, for the accurate detection of the P wave, QRS complex, and ST segment of the ECG signal. We then catagorited and tabulated these cardiac disorders in terms of heart rate, PR interval, QRS width, and P wave amplitude. Finally, we discussed the characteristics and different methods (and their measures) of analyting the heart rate variability (HRV) signal, derived from the ECG waveform. The HRV signals are characterised in terms of these measures, then fed into classifiers for grouping into categories (for normal subjects and for disorders such as cardiac disorders and diabetes) for carrying out diagnosis.

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Giant negative T-wave: always coronary artery disease?

Italian Journal of Medicine ◽

10.4081/itjm.2007.1.55 ◽

2013 ◽

pp. 55-56

Author(s):

F. Dall’Orto ◽

A. Reverzani ◽

F. Maselli ◽

G. Gambarati ◽

G. Chesi

Keyword(s):

Coronary Artery Disease ◽

Clinical Case ◽

Bundle Branch Block ◽

Long Period ◽

T Wave ◽

Artery Disease ◽

Pace Maker ◽

Electrocardiogram Ecg ◽

Total Atrioventricular Block ◽

T Waves

CLINICAL CASE We describe a 82 years old patient with giant negative T waves in anterior and inferior leads at electrocardiogram (ECG) after pace-maker (PM) implantation because of total atrioventricular block, and we discuss about different cause of negative T waves at ECG. CONCLUSIONS Particularly, we remark that, after a long period of PM stimulation, a negative T waves at ECG without myocardial ischemia, defined as “electrical memory”, may appear if a spontaneous sinus rhythm occurs. The same phenomena is present in patients affected by intermittent left bundle-branch block.

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Electrocardiogram Changes with Acute Alcohol Intoxication: A Systematic Review

The Open Cardiovascular Medicine Journal ◽

10.2174/1874192401812010001 ◽

2018 ◽

Vol 12 (1) ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

Hitesh Raheja ◽

Vinod Namana ◽

Kirti Chopra ◽

Ankur Sinha ◽

Sushilkumar Satish Gupta ◽

...

Keyword(s):

Cardiac Arrhythmias ◽

Alcohol Intoxication ◽

P Wave ◽

Acute Alcohol Intoxication ◽

Qrs Complex ◽

Qtc Prolongation ◽

Ecg Changes ◽

T Wave ◽

St Segment ◽

Electrocardiogram Ecg

Background: Acute alcohol intoxication has been associated with cardiac arrhythmias but the electrocardiogram (ECG) changes associated with acute alcohol intoxication are not well defined in the literature. Objective: Highlight the best evidence regarding the ECG changes associated with acute alcohol intoxication in otherwise healthy patients and the pathophysiology of the changes. Methods: A literature search was carried out; 4 studies relating to ECG changes with acute alcohol intoxication were included in this review. Results: Of the total 141 patients included in the review, 90 (63.8%) patients had P-wave prolongation, 80 (56%) patients had QTc prolongation, 19 (13.5%) patients developed T-wave abnormalities, 10 (7%) patients had QRS complex prolongation, 3 (2.12%) patients developed ST-segment depressions. Conclusion: The most common ECG changes associated with acute alcohol intoxication are (in decreasing order of frequency) P-wave and QTc prolongation, followed by T-wave abnormalities and QRS complex prolongation. Mostly, these changes are completely reversible.

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RELATIONSHIP AMONG QRS COMPLEX CHARACTERS IN ELECTROCARDIOGRAM AND ITS APPLICATION TO MYOCARDIAL ISCHEMIA

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519411004745 ◽

2012 ◽

Vol 12 (03) ◽

pp. 1250036 ◽

Cited By ~ 1

Author(s):

JINZHONG SONG ◽

HONG YAN ◽

XINMING YU ◽

YUHUA YAO ◽

HUA CHEN ◽

...

Keyword(s):

Heart Rate ◽

Myocardial Ischemia ◽

Action Potentials ◽

Qrs Complex ◽

Clinical Appearance ◽

T Complex ◽

Normal States ◽

Electrocardiogram Ecg ◽

Ventricular Depolarization ◽

Complex Characters

Electrocardiogram (ECG) is a noninvasive, economic, and convenient detecting tool in myocardial ischemia (MI), and its clinical appearance is mainly exhibited by ST-T complex changes. Recently, QRS complex characters in detecting MI were proposed by an increasing number of researchers. In this paper, various QRS complex characters were extracted in ECG, and their relationship was analyzed systematically. As a result, these characters were divided into two groups, and there was good correlation among them in each group, while the correlation between the groups was poor. Finally, these QRS complex characters were applied to myocardial ischemia, and five characters had significant differences after 59 normal ECG recordings verification, which were: QRS upward and downward slopes, transient heart rate, angle R and angle Q in a triangle QRS. Experimental results showed it was apparent that the trend changes of these five characters when MI events occurred were consistent with their relationship. The conduction velocity of action potentials in ventricular depolarization is slower in MI states than in normal states.

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A novel signal-adaptive multi-feature extraction algorithm for arrhythmia detection

Bulletin of the National Research Centre ◽

10.1186/s42269-021-00609-8 ◽

2021 ◽

Vol 45 (1) ◽

Author(s):

L. B. Vinutha ◽

P. S. Ramkumar ◽

Rajashekar Kunabeva

Keyword(s):

Heart Rate ◽

Feature Extraction ◽

Bundle Branch Block ◽

Arrhythmia Detection ◽

White Syndrome ◽

Ecg Signals ◽

T Wave ◽

Complex Morphology ◽

Extraction Algorithm ◽

Wolff Parkinson White Syndrome

Abstract Background The significant features like an amplitude and intervals of electrocardiograph or P-QRS-T wave represent the functionality of the heart. Accurate extraction of these features helps in capturing characteristics of the signal helpful for the detection of cardiac abnormalities. In this paper, a novel signal folding-based algorithm is proposed to obtain detailed information about the complex morphology of signal. It explores the denoising and feature extraction of the specific ECG signals. Results The experimental study conducted using MIT-BIH Arrhythmia database ECG records with known conditions of left bundle branch block, right bundle branch block, Wolff-Parkinson-White syndrome beats has been considered. Heart rate values for selected ECG records from MIT-BIH dataset and synthetic signals from ECG simulator yielded the same values and thus validate our approach. Conclusion The proposed algorithm determines the heart rate, percentage leakage around the peak and is capable of folding a signal very efficiently based on detected R peaks and period-dependent gate(window).

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Research on the Values of Amplitudes of Electrocardiographic Waves Depending on Age in Kids

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca Veterinary Medicine ◽

10.15835/buasvmcn-vm:2020.0019 ◽

2020 ◽

Vol 77 (2) ◽

pp. 80

Author(s):

Dragos Corneliu COTOR ◽

Gabriel GAJAILA ◽

Aurel DAMIAN ◽

Ana Maria ZAGRAI ◽

Carmen PETCU ◽

...

Keyword(s):

Statistical Analysis ◽

Electric Activity ◽

P Wave ◽

Mechanical Activity ◽

Qrs Complex ◽

T Wave ◽

Electrocardiogram Ecg

The electrocardiogram (ECG) is a graphical recording of the cardiac electric activity during cardiac revolutions. This bio-current triggers and maintains the mechanical activity of the heart. Within this research, the amplitudes values of the electrocardiographic waves were determined in 6 leads: I, II, III, aVL, aVR and aVF. Thus, some electrocardiograms were recorded using limb lead in clinically healthy kids, aged 1 month, 3 months and 5 months, in order to achieve the proposed objectives. Then, the statistical analysis of the obtained results was performed using t (student) test.As a consequence of the interpretation of the obtained results, it was noticed that the limb leads can be used successfully for recording the electrocardiogram in kids because it provides an easy aspect to interpret. The highest amplitude of the electrocardiographic waves is recorded in I lead, in the case of the 1 month old kids (having the following values: 0.115 mV ± 0.010 for P wave; 0.625 mV ± 0.078 for QRS complex; 0.460 mV ± 0.045 for T wave) and in II lead (having the following values for the 3 months old kids: 0.071 mV ± 0.015 for P wave; 0.540 mV ± 0.064 for QRS complex; 0.310 mV ± 0.052 for T wave and having the following values for the 5 months old kids: 0.071 mV ± 0.015 for P wave; 0.455 mV ± 0.028 for QRS complex; 0.430 mV ± 0.026 for T wave). It also found that the lowest amplitude of electrocardiographic waves is recorded in the aVF lead, but this lead cannot be used for ECG recording in kids.

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Heart rate variability and electrocardiogram waveform as predictors of morbidity during hypothermia and rewarming in rats

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y02-120 ◽

2002 ◽

Vol 80 (9) ◽

pp. 925-933 ◽

Cited By ~ 13

Author(s):

C B Matthew ◽

A M Bastille ◽

R R Gonzalez ◽

I V Sils

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Wave Amplitude ◽

Sodium Pentobarbital ◽

Sprague Dawley ◽

T Wave ◽

Sprague Dawley Rats ◽

Copper Tubing ◽

Electrocardiogram Ecg

This study examined electrocardiogram (ECG) waveform, heart rate (HR), mean blood pressure (BP), and HR variability as potential autonomic signatures of hypothermia and rewarming. Adult male SpragueDawley rats had telemetry transmitters surgically implanted, and 2 weeks were allowed for recovery prior to induction of hypothermia. Rats were lightly anesthetized (sodium pentobarbital, 35 mg/kg i.p.) and placed in a coil of copper tubing through which temperature-controlled water was circulated. Animals were cooled to a core temperature (Tc) of 20°C, maintained there for 30 min, and then rewarmed. Data (Tc, BP, HR from ECG, and 10-s strips of ECG waveforms) were collected every 5 min throughout hypothermia and rewarming. Both HR and BP declined after initial increases with the drop in HR starting at a higher Tc than the drop in BP (29.6 ± 2.4°C vs. 27.1 ± 3.3°C, p < 0.05). Animals that were not successfully rewarmed exhibited a significant (p < 0.05) increase in the normalized standard deviation of interbeat intervals (IBI) throughout cooling compared with animals that were successfully rewarmed. The T wave of the ECG increased in amplitude and area with decreasing Tc. T-wave amplitude and IBI variability show potential as predictors of survival in hypothermic victims.Key words: hypothermia, rewarming, heart rate variability, ECG, blood pressure.

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Electrocardiogram of Clinically Healthy Mithun (Bos frontalis): Variation among Strains

Veterinary Medicine International ◽

10.4061/2010/790310 ◽

2010 ◽

Vol 2010 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Sagar Sanyal ◽

Pradip Kumar Das ◽

Probal Ranjan Ghosh ◽

Kinsuk Das ◽

Kezha V. Vupru ◽

...

Keyword(s):

Heart Rate ◽

Respiration Rate ◽

Rectal Temperature ◽

The Other ◽

P Wave ◽

Qrs Complex ◽

T Wave ◽

Genetic Strains ◽

The Mean ◽

Bovine Species

A study was conducted to establish the normal electrocardiogram in four different genetic strains of mithun (Bos frontalis). Electrocardiography, cardiac electrical axis, heart rate, rectal temperature and respiration rate were recorded in a total of 32 adult male mithun of four strains ( each). It was found that the respiration and heart rates were higher () in Manipur than other three strains. Amplitude () and duration of P wave and QRS complex differed () among the strains. Mizoram strain had the highest amplitude and duration of P wave and QRS complex. On the other hand, higher () amplitude and duration of T wave were recorded in Arunachalee and Mizoram strains. The mean electrical axis of QRS complex that were recorded for Arunachalee and Manipur strains were similar to that reported for other bovine species; whereas the electrical axis of QRS for Nagamese and Mizoram strains were more close to feline and caprine species, respectively. In conclusion, electrocardiogram of mithun revealed that the amplitude and duration of P wave, QRS complex and T wave were different among four different genetic strains of mithun and the electrical axis of QRS complex for Nagamese and Mizoram mithuns are dissimilar to bovine species.

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Opening the black box: interpretability of machine learning algorithms in electrocardiography

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2020.0253 ◽

2021 ◽

Vol 379 (2212) ◽

Cited By ~ 1

Author(s):

Matteo Bodini ◽

Massimo W. Rivolta ◽

Roberto Sassi

Keyword(s):

Machine Learning ◽

Machine Learning Algorithms ◽

P Wave ◽

Qrs Complex ◽

Ecg Signals ◽

T Wave ◽

Cardiac Abnormalities ◽

Challenges And Opportunities ◽

Clinically Significant ◽

Electrocardiogram Ecg

Recent studies have suggested that cardiac abnormalities can be detected from the electrocardiogram (ECG) using deep machine learning (DL) models. However, most DL algorithms lack interpretability, since they do not provide any justification for their decisions. In this study, we designed two new frameworks to interpret the classification results of DL algorithms trained for 12-lead ECG classification. The frameworks allow us to highlight not only the ECG samples that contributed most to the classification, but also which between the P-wave, QRS complex and T-wave, hereafter simply called ‘waves’, were the most relevant for the diagnosis. The frameworks were designed to be compatible with any DL model, including the ones already trained. The frameworks were tested on a selected Deep Neural Network, trained on a publicly available dataset, to automatically classify 24 cardiac abnormalities from 12-lead ECG signals. Experimental results showed that the frameworks were able to detect the most relevant ECG waves contributing to the classification. Often the network relied on portions of the ECG which are also considered by cardiologists to detect the same cardiac abnormalities, but this was not always the case. In conclusion, the proposed frameworks may unveil whether the network relies on features which are clinically significant for the detection of cardiac abnormalities from 12-lead ECG signals, thus increasing the trust in the DL models. This article is part of the theme issue ‘Advanced computation in cardiovascular physiology: new challenges and opportunities’.

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