Antidromic His capture during entrainment of orthodromic AVRT.
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.
Nair
Krishnakumar
K
The Hull Family Ventricular Fibrillation Management Laboratory, University Health Network, Toronto, Ontario, Canada. krishnakumar.nair@uhn.on.ca
Selvaraj
Raja
R
Farid
Talha
T
Nanthakumar
Kumaraswamy
K
D002036:Bundle of His / Q000503:physiopathology*; D017115:Catheter Ablation; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008875:Middle Aged; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*; D016896:Treatment Outcome