Ventriculoatrial block during atrioventricular nodal reentrant tachycardia utilizing multiple retrograde pathways.
A rare case of narrow QRS tachycardia continuing despite the occurrence of VA block is reported. Right ventricular stimulation suggested dual AV nodal physiology. The tachycardia was induced by ventricular premature stimulation, which failed to depolarize the atrium. Two types of tachycardia that had different retrograde conduction sequences, HA intervals, and cycle lengths were induced. The occurrence of VA block did not terminate the tachycardia but transiently prolonged the tachycardia cycle length. These findings suggest the mechanism is AV nodal reentry utilizing multiple retrograde pathways with intranodal reentry bridging the VA block and maintaining the tachycardia.
Ino
T
T
Department of Internal Medicine, Tama-Nagayama Hospital, Nippon Medical School, Tokyo, Japan. ti@nms.ac.jp
Tadera
T
T
Miyamoto
S
S
Tanaka
K
K
Ohno
T
T
Nagasawa
K
K
Hayakawa
H
H
D002036:Bundle of His / Q000503:physiopathology; D004558:Electric Stimulation; D006327:Heart Block / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology*; D006329:Heart Conduction System / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009434:Neural Pathways / Q000502:physiology; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology*; D016276:Ventricular Function