Clinical, electrocardiographic, and diagnostic imaging features and outcomes in cats with electrocardiographic diagnosis of ventricular pre-excitation: a retrospective study of 23 cases (2010-2022)

E A Gavic; C D Stauthammer; A K Masters; K R S Morgan; A Rendahl; M Ciccozzi; K Beekmann; R George; E Herrold; L E Markovic; K Schober; S S Tjostheim; K Wright

doi:10.1016/j.jvc.2024.09.003

Clinical, electrocardiographic, and diagnostic imaging features and outcomes in cats with electrocardiographic diagnosis of ventricular pre-excitation: a retrospective study of 23 cases (2010-2022)

J Vet Cardiol. 2024 Sep 20:56:97-109. doi: 10.1016/j.jvc.2024.09.003. Online ahead of print.

Authors

E A Gavic¹, C D Stauthammer², A K Masters², K R S Morgan², A Rendahl², M Ciccozzi², K Beekmann³, R George⁴, E Herrold⁵, L E Markovic⁶, K Schober⁵, S S Tjostheim⁷, K Wright³

Affiliations

¹ University of Minnesota, Veterinary Medical Center, Cardiology Department, 1365 Gortner Avenue, Saint Paul, MN 55108, USA. Electronic address: [email protected].
² University of Minnesota, Veterinary Medical Center, Cardiology Department, 1365 Gortner Avenue, Saint Paul, MN 55108, USA.
³ MedVet Cincinnati, 3964 Red Bank Road, Fairfax, OH 45227, USA.
⁴ Animal Emergency and Referral Center of Minnesota, 1160 Helmo Avenue North, Oakdale, MN 55128, USA.
⁵ The Ohio State University Veterinary Medical Center, 601 Vernon L Tharp Street, Columbus, OH 43210, USA.
⁶ Department of Small Animal Medicine and Surgery, University of Georgia, College of Veterinary Medicine, 501 D. W. Brooks Drive, Athens, GA 30602, USA.
⁷ Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin, 2015 Linden Drive, Madison, WI 53706, USA.

PMID: 39423603
DOI: 10.1016/j.jvc.2024.09.003

Abstract

Introduction/objectives: Ventricular pre-excitation (VPE) occurs when atrial electrical impulses prematurely excite the ventricles through an aberrant muscle bundle known as an accessory pathway (AP). Orthodromic atrioventricular reciprocating tachycardia is a re-entrant, narrow complex supraventricular tachycardia (SVT), maintained through retrograde conduction over an AP. The study aimed to describe patient signalments, clinical signs, electrocardiographic (ECG) and diagnostic imaging features, treatments, prognostic variables, and outcomes in cats with ECG diagnosis of VPE.

Animals: Twenty-three cats diagnosed with VPE between January 2010 and August 2022 were included in this study.

Materials and methods: This was a multicenter, retrospective study with twenty-three cats diagnosed with VPE between January 2010 and August 2022. Ventricular pre-excitation diagnosis was based on ECG evidence of shortened PR interval, delta wave, and prolonged QRS duration. The median survival time (MST) was estimated by the Kaplan-Meier curve. Log-rank tests were performed to assess for an association between clinical signs or presence of structural heart disease on the MST.

Results: Fourteen (60.8%) cats with VPE also had SVT documented on ECG, with 7 of 14 with ECG confirmation of orthodromic atrioventricular reciprocating tachycardia. Four (17.4%) cats had suspected AP-mediated tachyarrhythmia based on associated clinical signs. Common presenting signs included collapse (15/23; 65.2%) and respiratory distress (14/23; 60.8%). Five (21.7%) cats were asymptomatic. Heart rate during SVT ranged from 310 to 420 bpm (median: 375 bpm). Initial treatment included atenolol (10/18), sotalol (5/18), diltiazem (2/18), and amiodarone (1/18). From the date of diagnosis, MST was 1872 days (5.1 years).

Conclusions: The majority of cats with VPE also had symptomatic SVT. The prognosis for cats with VPE is considered good with an MST of greater than five years.

Keywords: Congestive heart failure; Feline; Orthodromic atrioventricular reciprocating tachycardia; Supraventricular tachycardia; Wolff-Parkinson-White syndrome.