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Updated: Jun 14, 2026

Electrophysiological Assessment of Murine Atria with High-Resolution Optical Mapping
Published on: February 22, 2018
Antidromic His capture during entrainment of orthodromic AVRT
Krishnakumar Nair1, Raja Selvaraj, Talha Farid
1The Hull Family Ventricular Fibrillation Management Laboratory, University Health Network, Toronto, Ontario, Canada. krishnakumar.nair@uhn.on.ca
Abstract:
A narrow QRS tachycardia with eccentric atrial activation is presented with features favoring an orthodromic atrioventricular re-entrant tachycardia including an extranodal paraHisian response, and a short corrected post-pacing interval to tachycardia cycle length difference following right ventricular entrainment. However, during entrainment, the H-H interval was entrained by the pacing train several beats prior to the A-A interval which would suggest an atrioventricular nodal re-entry tachycardia. We discuss the diagnosis and its mechanism.
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