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Journal of veterinary internal medicine2015; 29(3); 946-953; doi: 10.1111/jvim.12606

Risk factors for recurrence of atrial fibrillation in horses after cardioversion to sinus rhythm.

Abstract: Although atrial fibrillation (AF) can be successfully treated in horses, recurrence occurs frequently. In humans, atrial function after cardioversion can predict recurrence. Objective: To examine the prognostic value of atrial mechanical function at 24 hours after cardioversion and other potential predictor variables for AF recurrence in horses. Methods: 117 horses treated for AF at 4 referral centers. Methods: Retrospective study. Inclusion criteria were successful cardioversion, echocardiography at 24 hours after cardioversion and ≥4 months follow-up. To determine factors associated with AF recurrence, a multivariable survival model was built. Results: 133 AF episodes in 117 horses were included. AF recurred in 36/100 horses with a first AF episode and in 57/133 AF episodes overall. Factors associated with recurrence in horses with a first episode were previous unsuccessful treatment attempt (hazard ratio HR 2.36, 95% confidence interval CI 1.11-4.99, P = .025) and mild or moderate mitral regurgitation (HR 2.70, 95% CI 1.23-5.91, P = .013). When the last AF episode of all horses was included, previous AF (HR 2.53, 1.33-4.82, P = .005) and active left atrial fractional area change ≤9.6% (HR 3.43, 1.22-9.67, P = .020) were significant predictors. Conclusions: The only echocardiographic variable of left atrial function with significant prognostic value for recurrence was low active left atrial fractional area change. Further research is necessary to evaluate whether echocardiography at a later timepoint could provide more prognostic information.
Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
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Publication Date: 2015-04-27 PubMed ID: 25917409PubMed Central: PMC4895430DOI: 10.1111/jvim.12606Google 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.

The research investigates the factors contributing to the recurrence of atrial fibrillation in horses after undergoing a certain heart procedure called cardioversion. It concluded that prior unsuccessful treatment attempts, mild or moderate mitral regurgitation, and a low active left atrial fractional area change are key indicators of recurrence.

Objective and Methodology

  • The research sought to identify the predictors of atrial fibrillation (AF) recurrence in horses after they have been treated through cardioversion.
  • The researchers utilized a retrospective study where they included cases of 117 horses who had received treatment for AF at four referral centers.
  • The horses must have successfully underwent cardioversion, had an echocardiography 24 hours after cardioversion, and had a minimum follow-up period of four months in order to qualify for the study.
  • The researchers then built a multivariable survival model to determine the factors that were associated with the recurrence of AF.

Results

  • The study included a total of 133 AF episodes from the 117 horses. Of these, recurrence of AF was found in 36 of the 100 horses experiencing their first AF episode, and in 57 of the 133 total AF occurrences.
  • The study found that in horses experiencing their first AF episode, factors such as having had a previous unsuccessful treatment attempt and exhibiting mild or moderate mitral regurgitation were associated with AF recurrence.
  • When considering the last AF episode of all horses, previous occurrence of AF and an active left atrial fractional area change of less than or equal to 9.6% were found to be significant predictors of recurrence.

Conclusion

  • The only echocardiographic variable of left atrial function that held significant prognostic value for predicting recurrence was a low active left atrial fractional area change.
  • The researchers suggest that further studies need to be carried out to determine if conducting echocardiography at a later timepoint could provide more valuable prognostic information.

Cite This Article

APA
Decloedt A, Schwarzwald CC, De Clercq D, Van Der Vekens N, Pardon B, Reef VB, van Loon G. (2015). Risk factors for recurrence of atrial fibrillation in horses after cardioversion to sinus rhythm. J Vet Intern Med, 29(3), 946-953. https://doi.org/10.1111/jvim.12606

Publication

Journal of veterinary internal medicine
ISSN: 1939-1676
NlmUniqueID: 8708660
Country: United States
Language: English
Volume: 29
Issue: 3
Pages: 946-953

Researcher Affiliations

Decloedt, A
  • Department of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, 9820, Belgium.
Schwarzwald, C C
  • Clinic for Equine Internal Medicine, Vetsuisse Faculty, University of Zurich, Zurich, 8057, Switzerland.
  • Department of Veterinary Clinical Sciences, The Ohio State University, Columbus, OH, 43210.
De Clercq, D
  • Department of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, 9820, Belgium.
Van Der Vekens, N
  • Department of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, 9820, Belgium.
Pardon, B
  • Department of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, 9820, Belgium.
Reef, V B
  • Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA, 19348.
van Loon, G
  • Department of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, 9820, Belgium.

MeSH Terms

  • Animals
  • Atrial Fibrillation / etiology
  • Atrial Fibrillation / therapy
  • Atrial Fibrillation / veterinary
  • Echocardiography / veterinary
  • Electric Countershock / veterinary
  • Female
  • Horse Diseases / etiology
  • Horse Diseases / therapy
  • Horses
  • Male
  • Prognosis
  • Recurrence
  • Retrospective Studies
  • Risk Factors

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Citations

This article has been cited 15 times.
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