Localization and characterization of atrial depolarization waves on the surface electrocardiogram in dogs with rapid supraventricular tachycardia

Abstract

BackgroundSupraventricular tachycardias (SVTs), despite having various anatomical substrates and pathophysiological mechanisms, frequently show similar electrocardiographic presentations.ObjectivesTo locate and characterize atrial deflections (ADs) on 12‐lead electrocardiograms in dogs with sustained rapid SVT and assess the utility of different electrocardiographic variables in differentiating types of tachycardia.AnimalsNinety‐two dogs with orthodromic atrioventricular reciprocating tachycardia, 17 with atrial flutter, 33 with focal atrial tachycardia recorded and confirmed by electrophysiological study, and 40 dogs with sinus tachycardia.MethodsAtrial deflection position on the 12‐lead surface electrocardiogram was assessed according to the sequence of intracardiac activation. Its features were evaluated together with the relationship between AD and QRS complex interval (AD‐R) and QRS complex and AD interval (R‐AD).ResultsOrthodromic atrioventricular reciprocating tachycardia was characterized by an AD‐AD interval of 213 ± 30 ms, mean electrical axis (MEA) of AD of −90 (−90/−78)°, R‐AD interval of 75 (65‐80) ms, and R‐AD/AD‐R of 0.54 (0.45‐0.64). Atrial flutter was characterized by an AD‐AD interval of 199 ± 57 ms, MEA of 76° (72/81), R‐AD of 120 (72‐144) ms, and R‐AD/AD‐R of 0.81 (0.63‐1.13). Focal atrial tachycardia was characterized by an AD‐AD interval of 270 ± 38 ms, MEA of 49 (−72/76)°, R‐AD of 160 (120‐200) ms, and R‐AD/AD‐R of 1.45 (0.92‐1.67). Sinus tachycardia was characterized by an AD‐AD interval of 292 ± 31 ms, MEA of 66° (52/73), R‐AD of 215 (192‐222) ms, and R‐AD/AD‐R of 2.68 (2.25‐3.08).Conclusions and Clinical ImportanceAnalyzing AD on 12‐lead electrocardiogram is helpful in differentiating the most common SVTs in dogs.

Successful high-resolution three-dimensional electroanatomical mapping and radiofrequency catheter ablation of a posteroseptal accessory pathway in a dog using CARTO 3

“…2), both QRS electrical alternans and TWA were observed simultaneously. QRS electrical alternans is common in human patients and dogs with OAVRT and is by most considered heart rate-dependent [4]. On the other hand, TWA could signal inhomogeneous tissue refractoriness [7] and may be related to an increased risk of sudden cardiac death in Doberman Pinschers [8].…”

“…Other than TWA, the above findings in dogs are most indicative of OAVRT and less so of atrial tachycardia and atrioventricular nodal re-entrant tachycardia [2][3][4]. Right atrial activation mapping during tachycardia revealed the earliest site of activation right postero-septal near the tricuspid annulus (Fig.…”

A new bipolar precordial electrocardiographic lead configuration for specific evaluation of atrial depolarization in healthy dogs

“…[7][8][9] Also in veterinary practice, identifying the P waves is essential for differentiating between various types of supraventricular tachycardia, such as AFL, AT, orthodromic atrioventricular reciprocating tachycardia, and sinus tachycardia. 10 However, there has not been an equivalent method to the Lewis lead proposed in veterinary medicine, and the Lewis lead configuration described in humans cannot be directly translated to dogs due to differences in the anatomical and electrical axes of the heart across species. 11,12 Therefore, this study proposes new bipolar lead configurations to specifically evaluate atrial depolarization in dogs and investigate their characteristics by comparing them with conventional leads.…”