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Home / Equine Research Bank / Sci Rep / The complexity of clinically-normal sinus-rhythm ECGs is dec...
Scientific reports2020; 10(1); 6822; doi: 10.1038/s41598-020-63343-7

The complexity of clinically-normal sinus-rhythm ECGs is decreased in equine athletes with a diagnosis of paroxysmal atrial fibrillation.

Abstract: Equine athletes have a pattern of exercise which is analogous to human athletes and the cardiovascular risks in both species are similar. Both species have a propensity for atrial fibrillation (AF), which is challenging to detect by ECG analysis when in paroxysmal form. We hypothesised that the proarrhythmic background present between fibrillation episodes in paroxysmal AF (PAF) might be detectable by complexity analysis of apparently normal sinus-rhythm ECGs. In this retrospective study ECG recordings were obtained during routine clinical work from 82 healthy horses and from 10 horses with a diagnosis of PAF. Artefact-free 60-second strips of normal sinus-rhythm ECGs were converted to binary strings using threshold crossing, beat detection and a novel feature detection parsing algorithm. Complexity of the resulting binary strings was calculated using Lempel-Ziv ('76 & '78) and Titchener complexity estimators. Dependence of Lempel-Ziv '76 and Titchener T-complexity on the heart rate in ECG strips obtained at low heart rates (25-60 bpm) and processed by the feature detection method was found to be significantly different in control animals and those diagnosed with PAF. This allows identification of horses with PAF from sinus-rhythm ECGs with high accuracy.
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Publication Date: 2020-04-22 PubMed ID: 32321950PubMed Central: PMC7176685DOI: 10.1038/s41598-020-63343-7Google Scholar: Lookup
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  • Non-U.S. Gov't

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research study used ECG complexity analysis to detect paroxysmal atrial fibrillation in equine athletes, a potentially serious condition which can be hard to identify when not active.

Overview of the Study

  • This research was completed as a retrospective study and used ECG recordings from 82 healthy horses alongside 10 horses diagnosed with paroxysmal atrial fibrillation (PAF).
  • Through the methodology used, the researchers hypothesized that they could detect the proarrhythmic background present between fibrillation episodes in PAF by conducting analysis on seemingly normal sinus-rhythm ECGs.
  • Once collected, artefact-free 60-second strips of these normal sinus-rhythm ECGs were then converted into binary strings using a series of steps: threshold crossing, beat detection, and the application of a novel feature detection parsing algorithm.

Complexity Analysis

  • The complexity of these binary strings was subsequently calculated using the Lempel-Ziv (’76 & ’78) and Titchener complexity estimators.
  • These complexity estimators are algorithms developed for the purposes of effectively gauging the complexity of a binary sequence.

Results

  • The researchers found a significant difference between control animals and those diagnosed with PAF in the dependence of Lempel-Ziv ’76 and Titchener T-complexity on the heart rate in ECG strips obtained at low rates (25-60 bpm) and processed through their feature detection method.
  • This significant difference allowed the researchers to identify horses with PAF from sinus-rhythm ECGs at a high level of accuracy.

Implications of the Study

  • The study provides an advanced method for identifying equine athletes at risk of PAF with a high degree of precision, even when fibrillation episodes are inactive.
  • Further application of these methods could further enhance the understanding and detection of arrhythmic disorders not just in equine but potentially also in human athletes where similar physiological patterns apply.

Cite This Article

APA
Alexeenko V, Fraser JA, Bowen M, Huang CL, Marr CM, Jeevaratnam K. (2020). The complexity of clinically-normal sinus-rhythm ECGs is decreased in equine athletes with a diagnosis of paroxysmal atrial fibrillation. Sci Rep, 10(1), 6822. https://doi.org/10.1038/s41598-020-63343-7

Publication

Scientific reports
ISSN: 2045-2322
NlmUniqueID: 101563288
Country: England
Language: English
Volume: 10
Issue: 1
Pages: 6822

Researcher Affiliations

Alexeenko, Vadim
  • Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7AL, United Kingdom.
  • Physiological Laboratory, University of Cambridge, Cambridge, CB2 3DY, United Kingdom.
Fraser, James A
  • Physiological Laboratory, University of Cambridge, Cambridge, CB2 3DY, United Kingdom.
Bowen, Mark
  • Faculty of Medicine & Health Sciences, University of Nottingham, Nottingham, NG7 2UH, United Kingdom.
Huang, Christopher L-H
  • Physiological Laboratory, University of Cambridge, Cambridge, CB2 3DY, United Kingdom.
  • Division of Cardiovascular Biology, Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, United Kingdom.
Marr, Celia M
  • Rossdales Equine Hospital and Diagnostic Centre, Exning, CB8 7NN, Suffolk, United Kingdom.
Jeevaratnam, Kamalan
  • Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7AL, United Kingdom. drkamalanjeeva@gmail.com.
  • Physiological Laboratory, University of Cambridge, Cambridge, CB2 3DY, United Kingdom. drkamalanjeeva@gmail.com.

MeSH Terms

  • Animals
  • Arrhythmias, Cardiac / complications
  • Arrhythmias, Cardiac / diagnostic imaging
  • Arrhythmias, Cardiac / physiopathology
  • Atrial Fibrillation / diagnosis
  • Atrial Fibrillation / diagnostic imaging
  • Atrial Fibrillation / physiopathology
  • Atrial Fibrillation / veterinary
  • Coronary Sinus / diagnostic imaging
  • Coronary Sinus / physiopathology
  • Electrocardiography / veterinary
  • Heart Rate / physiology
  • Horses / physiology

Conflict of Interest Statement

The authors declare no competing interests.

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Citations

This article has been cited 8 times.
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