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Equine veterinary journal2020; 53(5); 955-963; doi: 10.1111/evj.13372

Implantable loop recorders can detect paroxysmal atrial fibrillation in Standardbred racehorses with intermittent poor performance.

Abstract: Limited information is available on paroxysmal atrial fibrillation (PAF) in the horse. Indeed, undiagnosed PAF could result in poor performance. Due to the intermittent occurrence, PAF is difficult to diagnose. However, implanting a small ECG device (implantable loop recorder, ILR) subcutaneously, allows the continuous and automatic detection of PAF. Objective: The aim was to investigate the potential of ILRs as a tool for diagnosing PAF in horses with poor performance. Methods: Prospective field study. Methods: Twelve racing Standardbred trotters with intermittent reduced performance (mean age: six years) were enrolled prospectively. The ILR was implanted subcutaneously at the fifth or sixth left intercostal space and data from the ILR was collected during the study period in which the horses were followed for a median duration of 7.5 month (range 6-28). Results: The ILR was able to detect PAF in four out of twelve racehorses. The ILR also detected sustained atrial fibrillation (AF) in one horse during the study. The ILRs rely on RR detection and R waves were correctly identified in 96%. One hundred episodes were categorised as AF by the ILRs and subsequently visual ECG inspection categorised 12 as sinus rhythm (SR), 28 as sinus arrhythmia (SA), 14 as other arrhythmias and 46 as AF episodes. The Root Mean Square of the Successive Differences (RMSSD) values were significantly increased for AF compared to SR and SA. Conclusions: Few horses included and duration of study period varied among the horses. Further it was not possible to assess the sensitivity of the device in the current study and the ILRs proved to have a high rate of false positive misclassifications. Conclusions: This study indicates that ILRs can be used for detection of PAF episodes and could be a useful ECG tool for horses presenting with poor performance. This methodology provides a platform to facilitate the long-term assessment of AF development and quantification of AF burden in horses. Further studies including both healthy and poor performing horses are needed in order to learn more about PAF prevalence in racehorses.
© 2020 The Authors. Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.
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Publication Date: 2020-11-23 PubMed ID: 33113157PubMed Central: PMC8451893DOI: 10.1111/evj.13372Google Scholar: Lookup
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  • Journal Article

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 article investigates the potential of implantable loop recorders (ILR) as a tool for diagnosing paroxysmal atrial fibrillation (PAF) in racing Standardbred horses experiencing poor performance.

Research Objective

  • The focus of the study was to determine the effectiveness of ILRs in identifying episodes of PAF in racing Standardbred horses who demonstrated reduced performance or race results.

Methodology

  • A total of twelve racing Standardbred trotters with intermittent reduced performance were examined. The horses’ mean age was six years.
  • An ILR, a tiny ECG device, was implanted under the skin at the fifth or sixth intercostal space of the each horse.
  • Throughout the field study, which had a median duration of 7.5 months, data from the ILR was continuously collected and assessed.

Results

  • With the aid of the ILR, PAF was detected in four out of the twelve racehorses, and sustained atrial fibrillation (AF) in one horse during the examination period.
  • ILRs, which function on RR detection, accurately identified R waves in 96% of cases.
  • Of the 100 episodes recorded as AF by the ILRs, 12 were visually inspected and reclassified as sinus rhythm (SR), 28 as sinus arrhythmia (SA), 14 as other arrhythmias, and 46 were verified as AF episodes.
  • The Root Mean Square of the Successive Differences (RMSSD) values for AF were found to be notably higher compared to SR and SA.

Conclusions

  • The study faced limitations in terms of having a small cohort size and varying study durations for each horse.
  • An additional challenge was the inability to measure the sensitivity of the ILR within the confines of the study, and a notable number of false-positive misclassifications.
  • Despite these challenges, the study indicates that ILRs can effectively detect PAF episodes in horses and could serve as an effective ECG tool for racehorses experiencing poor performance.
  • This methodology also presents a basis on which to carry out long-term evaluation of AF development and for quantifying the AF burden in horses.
  • The researchers recommend further studies involving both healthy and poor-performing horses to better understand the prevalence of PAF in racehorses.

Cite This Article

APA
Buhl R, Nissen SD, Winther MLK, Poulsen SK, Hopster-Iversen C, Jespersen T, Sanders P, Carstensen H, Hesselkilde EM. (2020). Implantable loop recorders can detect paroxysmal atrial fibrillation in Standardbred racehorses with intermittent poor performance. Equine Vet J, 53(5), 955-963. https://doi.org/10.1111/evj.13372

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English
Volume: 53
Issue: 5
Pages: 955-963

Researcher Affiliations

Buhl, Rikke
  • Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Taastrup, Denmark.
Nissen, Sarah D
  • Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Taastrup, Denmark.
Winther, Marie L K
  • Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Taastrup, Denmark.
Poulsen, Sofie K
  • Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Taastrup, Denmark.
Hopster-Iversen, Charlotte
  • Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Taastrup, Denmark.
Jespersen, Thomas
  • Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
Sanders, Prashanthan
  • Centre for Heart Rhythm Disorders, Royal Adelaide Hospital and University of Adelaide, Adelaide, Australia.
Carstensen, Helena
  • Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Taastrup, Denmark.
Hesselkilde, Eva M
  • Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.

MeSH Terms

  • Animals
  • Atrial Fibrillation / diagnosis
  • Atrial Fibrillation / veterinary
  • Electrocardiography, Ambulatory
  • Horse Diseases / diagnosis
  • Horses
  • Prevalence
  • Prospective Studies
  • Prostheses and Implants

Grant Funding

  • DFF-7017-00050 / Independent Research Fund Denmark
  • Foreningen KUSTOS af 1881

Conflict of Interest Statement

No competing interests have been declared.

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Citations

This article has been cited 8 times.
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