Longitudinal dissociation in the his bundle: a possible mechanism of two distinct cycle lengths in atrioventricular reentrant tachycardia.
Two wide QRS tachycardias with identical morphology but different cycle lengths (CLs) developed in a 63-year-old man. Electrophysiological study demonstrated inducible atrioventricular reentrant tachycardia (AVRT) due to a concealed left posterior accessory pathway (AP), which was successfully ablated by radiofrequency application. Neither dual AV nodal pathways nor other APs were documented. Splitting of the His-bundle electrogram was shown, and programmed stimulation induced sudden prolongation of intra-hisian conduction time. These results suggest longitudinal dissociation in the His bundle may be responsible for two distinct CLs in AVRT without dual AV nodal physiology.
Akiyama
J
J
Department of Cardiology, Yokosuka Kyosai General Hospital, Japan.
Aonuma
K
K
Ogahara
S
S
Okamoto
Y
Y
Umezawa
S
S
Inada
M
M
Korenaga
M
M
Nogami
A
A
Hiroe
M
M
Marumo
F
F
Iesaka
Y
Y
D002036:Bundle of His / Q000503:physiopathology*; D017115:Catheter Ablation; D006801:Humans; D008297:Male; D008875:Middle Aged; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000503:physiopathology* / Q000628:therapy