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The Veterinary clinics of North America. Equine practice2019; 35(1); 85-102; doi: 10.1016/j.cveq.2018.12.004

Cardiac Arrhythmias in Horses.

Abstract: Arrhythmias are common in horses. Sinus arrhythmia and first- and second-degree atrioventricular block are frequently found physiologic arrhythmias, but should immediately disappear after stress or exercise. Atrial premature depolarizations are usually not associated with poor performance, but are a potential trigger for atrial fibrillation. Atrial fibrillation results in an abnormal ventricular response during exercise and poses a risk for collapse in some horses. This arrhythmia can usually be treated by quinidine sulfate or transvenous electrical cardioversion. Ventricular premature depolarizations, especially when associated with structural heart disease, may be a risk factor for ventricular tachycardia or even ventricular fibrillation.
Publication Date: 2019-03-11 PubMed ID: 30871832DOI: 10.1016/j.cveq.2018.12.004Google Scholar: Lookup
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Summary

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This research article explores the common occurrence of cardiac arrhythmias in horses, the physiological situations in which they occur and respective treatments. The focus includes sinus arrhythmias and first- and second-degree atrioventricular block through to more serious cases such as atrial fibrillation and ventricular premature depolarizations.

Physiological Arrhythmias in Horses

  • The paper discusses the common nature of sinus arrhythmias and first- and second-degree atrioventricular block in horses. These are considered physiological arrhythmias, meaning they occur as a natural part of the horse’s physical functioning.
  • These physiological arrhythmias should disappear after periods of stress or exercise, indicating that they are a temporary and somewhat expected response to certain conditions or activities.

Atrial Premature Depolarizations and Fibrillation

  • The article discusses atrial premature depolarizations, which are generally not associated with poor performance in horses. However, these depolarizations can be a potential trigger for atrial fibrillation, a more serious condition.
  • Atrial fibrillation is a concerning arrhythmia as it results in an abnormal ventricular response during exercise and can potentially cause horses to collapse. It requires treatment, usually via quinidine sulfate or transvenous electrical cardioversion—a treatment that uses electricity to reset the heart’s rhythm.

Ventricular Premature Depolarizations and Fibrillation

  • Ventricular premature depolarizations pose a more serious risk, especially when they occur in conjunction with structural heart disease. These have the potential to be a risk factor for more dangerous arrhythmias, such as ventricular tachycardia or even ventricular fibrillation.
  • Ventricular fibrillation is incredibly serious as it can quickly escalate to become a life-threatening condition. For this reason, understanding and identifying risk factors such as ventricular premature depolarizations can be critical in safeguarding the health of horses.

Cite This Article

APA
van Loon G. (2019). Cardiac Arrhythmias in Horses. Vet Clin North Am Equine Pract, 35(1), 85-102. https://doi.org/10.1016/j.cveq.2018.12.004

Publication

ISSN: 1558-4224
NlmUniqueID: 8511904
Country: United States
Language: English
Volume: 35
Issue: 1
Pages: 85-102

Researcher Affiliations

van Loon, Gunther
  • Department of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke 9820, Belgium. Electronic address: Gunther.vanLoon@UGent.be.

MeSH Terms

  • Animals
  • Arrhythmias, Cardiac / diagnosis
  • Arrhythmias, Cardiac / therapy
  • Arrhythmias, Cardiac / veterinary
  • Atrial Fibrillation / diagnosis
  • Atrial Fibrillation / therapy
  • Atrial Fibrillation / veterinary
  • Horse Diseases / diagnosis
  • Horse Diseases / therapy
  • Horses

Citations

This article has been cited 21 times.
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