Presented as an abstract at the 2007 ACVIM Forum, Seattle, WA.
Bradycardia-Associated Syncope in 7 Boxers with Ventricular Tachycardia (2002–2005)
Article first published online: 4 JUN 2008
Copyright © 2008 by the American College of Veterinary Internal Medicine
Journal of Veterinary Internal Medicine
Volume 22, Issue 4, pages 931–936, July–August 2008
How to Cite
Thomason, J.D., Kraus, M.S., Surdyk, K.K., Fallaw, T. and Calvert, C.A. (2008), Bradycardia-Associated Syncope in 7 Boxers with Ventricular Tachycardia (2002–2005). Journal of Veterinary Internal Medicine, 22: 931–936. doi: 10.1111/j.1939-1676.2008.0119.x
- Issue published online: 4 JUL 2008
- Article first published online: 4 JUN 2008
- Submitted November 15, 2007; Revised February 5, 2008; Accepted March 10 2008.
- Event recording;
- Holter recording;
- Neurocardiogenic bradycardia
Background: Syncope is a recognized problem in Boxers and often is the result of rapid ventricular tachycardia (VT). Affected dogs may have echocardiographic evidence of dilated cardiomyopathy, but frequently have normal echocardiograms. Although VT is probably the most common cause of syncope in Boxers, neurocardiogenic bradycardia can also occur.
Objective: We describe 7 Boxers with comorbid VT and neurocardiogenic bradycardia, wherein the syncope was secondary to bradycardia rather than VT.
Animals: Seven Boxers were selected from a larger population of Boxers with Holter-documented VT because these dogs had documented bradycardia at the time of syncope.
Methods: Retrospective study.
Results: Although all dogs had Holter-documented VT, the etiology of the syncopal episodes was consistent with neurocardiogenic bradycardia.
Clinical Importance: Neurocardiogenic bradycardia or VT can occur as isolated problems in Boxers. In some Boxers, VT and potential or manifest neurocardiogenic bradycardia coexist. The administration of a β-blocker or sotalol to such dogs can aggravate or precipitate neurocardiogenic bradycardia-related syncope.