Peer-reviewed veterinary case report
ECG signs of atrial depolarization in dogs with right-sided heart
By Maffei, A et al.·Published in Journal of veterinary cardiology : the official journal of the European Society of Veterinary Cardiology·2025·Clinica Veterinaria Malpensa, Italy·View original on PubMed →
PetCaseFinder translated the abstract of this peer-reviewed paper into plain English so pet owners can read it. We do not publish original research — every detail traces back to the citation above. How we work →
Original publication title: Atrial depolarization electrocardiographic features during orthodromic atrioventricular reciprocating tachycardia mediated by right-sided accessory pathway in the dog.
- Species:
- dog
Plain-English summary
A 5-year-old Beagle was brought in for rapid heartbeats and fainting episodes. The veterinarian performed an electrocardiogram (ECG) and found that the dog's heart was experiencing a specific type of abnormal rhythm called orthodromic atrioventricular reciprocating tachycardia (OAVRT), which is caused by an accessory pathway in the heart. While the study aimed to see if certain ECG features could help locate these pathways, it turned out that they weren't effective in pinpointing the exact location in dogs. The dog was treated with a procedure to ablate (destroy) the problematic pathway, which helped restore a normal heart rhythm.
People also search for: dog rapid heartbeat treatment · Beagle fainting episodes · OAVRT in dogs · accessory pathway heart condition in dogs
Abstract
INTRODUCTION/OBJECTIVES: Electrocardiographic features of atrial depolarization (AD) during orthodromic atrioventricular reciprocating tachycardia (OAVRT) have been widely studied to localize accessory pathways (APs) in humans. The aim of this study was to determine whether AD characteristics might also be used to determine AP anatomical sites in dogs. ANIMALS, MATERIALS AND METHODS: Clinical records of 83 dogs that underwent electrophysiologic studies for AP ablation were retrospectively analyzed. Accessory pathways were classified into three groups according to localization: right anterior (RA, 13.3%), right postero-septal (RPS, 36.1%), and right posterior (RP, 50.6%). Electrocardiographic characteristics of AD (duration, amplitude, and axis) and OAVRT (AD-AD, peak of R wave - atrial depolarization (R-AD)/atrial depolarization - peak of R wave (AD-R), peak to peak of R wave (RR) interval, and QT duration) were analyzed in all 12 leads. RESULTS: Mean AD duration in RA, RPS, and RP was 48.0 ± 10.3 ms, 46.1 ± 10.6 ms, and 47.1 ± 10.2 ms, respectively, and the mean amplitude was -0.25 ± 0.12 mV, -0.28 ± 0.20 mV, and -0.28 ± 0.18 mV, respectively. The median electrical axis on the frontal plane was -90.0° (interquartile range [IQR]: 26.5° in RA, 9.4° in RPS, and 13.9° in RP). The median AD-R, mean R-AD intervals, and mean R-AD/AD-R were 140.0 ms (IQR: 34.5 ms), 72.0 ± 19.3 ms, and 0.50 ± 0.14 in RA; 138.0 ms (IQR: 33.0 ms), 76.5 ± 13.6 ms, and 0.55 ± 0.15 in RPS; and 121.0 ms (IQR: 20.0 ms), 74.1 ± 11.7 ms, and 0.59 ± 0.15 in RP. No other statistically significant differences in electrocardiographic parameters were found. STUDY LIMITATIONS: Identification of ADs in some dogs was not straightforward, and thoracic conformation differences may have affected AD measurements. CONCLUSIONS: Electrocardiographic features of AD during OAVRT are not useful for localizing right-sided APs in dogs.
Find similar cases for your pet
PetCaseFinder finds other peer-reviewed reports of pets with the same symptoms, plus a plain-English summary of what was tried across them.
Search related cases →Original publication on PubMed: https://pubmed.ncbi.nlm.nih.gov/40577935/