Frequency of cardiac arrhythmias in horses during straight and untethered swimming.
- Observational Study
- Veterinary
- Journal Article
Summary
The research paper investigates the occurrence and frequency of cardiac arrhythmias in horses while they swim. Through observing sixteen horses during and after swimming, the study provides insight into whether swimming is a high-risk cardio-arrhythmic exercise for this animal.
Research Objective
The paper’s main objective is to describe the type and frequency of arrhythmias in horses during repetitive swimming sessions. In the past, cardiac arrhythmias have not been reported in horses during swimming. This research is an attempt to fill this knowledge gap.
Research Methods
- Sixteen horses were selected to swim five pool lengths of 75 meters each time, with each swim separated by a recovery walk.
- The recorded continuous electrocardiograms (ECGs) were analyzed during pre-swim, swim, and active-recovery periods.
- The arrhythmias were categorized into sinus arrhythmia (SA), sinus block, sinus pause (both compensatory and non-compensatory), second degree atrioventricular block (2AVB) for physiological arrhythmias, and supraventricular premature depolarisation (SVPD) and ventricular premature depolarisation (VPD) for non-physiological arrhythmias.
- A linear mixed-effects model was employed to study the effects of repetitive swimming lengths on arrhythmias and other swimming parameters.
Research Findings
- Among the 16 horses, 15 (94%) experienced at least one type of arrhythmia. However, the frequency of these arrhythmias was low.
- All types of arrhythmias, be it sinus blocks, sinus pauses, SA, SVPD, or VPD were recorded at least once during swimming. Except for one VPD coupling, all premature depolarisations were isolated incidents.
- During the active recovery phase, 13 horses (81%) displayed SA, six (38%) showed isolated SVPD, and one (6%) exhibited sinus pause. No VPD was recorded in this period.
Research Conclusion
The research concluded that despite the existence of arrhythmias in horses during swimming, the frequency remained low. Even rare pathological arrhythmias were observed during the repetitive swimming and active-recovery cycles. Thus, the study proposes that swimming along with active recovery periods does not pose a high-risk cardio-arrhythmic exercise for horses. The study was, however, limited by the relatively small number of horses utilized in the experiment, which impacts the assessment of population prevalence. For the first time, the research acquired high-quality underwater ECGs in swimming horses.
Cite This Article
Publication
Researcher Affiliations
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.
- Equine Veterinary Medical Center, Member of Qatar Foundation, Doha, Qatar.
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.
- Al Shaqab - Endurance Department, Member of Qatar Foundation, Doha, Qatar.
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.
- Equine Veterinary Medical Center, Member of Qatar Foundation, Doha, Qatar.
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.
MeSH Terms
- Horses
- Animals
- Swimming
- Arrhythmias, Cardiac / veterinary
- Electrocardiography / veterinary
- Heart Block / veterinary
- Horse Diseases
Grant Funding
- RG19_FD1 / Qatar Foundation
- University of Calgary
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