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.
Copyright © 2018 Elsevier Inc. All rights reserved.
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
Researcher Affiliations
- 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.- Schneider MJ, Piotrowski IL, Junge HK, van Steenkiste G, Vernemmen I, van Loon G, Schwarzwald CC. Application of Acoustic Cardiography in Assessment of Cardiac Function in Horses with Atrial Fibrillation Before and After Cardioversion. Animals (Basel) 2025 Jul 7;15(13).
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- Ibrahim L, Vernemmen I, Buschmann E, van Loon G, Cornillie P. Morphological variations of the interatrial septum and potential implications in equine cardiology. Sci Rep 2025 May 12;15(1):16500.
- Buschmann E, Van Steenkiste G, Vernemmen I, Demeyere M, Schauvliege S, Decloedt A, van Loon G. Caudal vena cava isolation using ablation index-guided radiofrequency catheter ablation (CARTO™ 3) to treat sustained atrial tachycardia in horses. J Vet Intern Med 2025 Jan-Feb;39(1):e17251.
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- Alberti E, Stucchi L, Lo Feudo CM, Stancari G, Conturba B, Ferrucci F, Zucca E. Evaluation of Cardiac Arrhythmias before, during, and after Treadmill Exercise Testing in Poorly Performing Standardbred Racehorses. Animals (Basel) 2021 Aug 16;11(8).
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