Alternate Ventriculo-Atrial Wenckebach Conduction during Ventricular Tachycardia

• Published in: Pacing and clinical electrophysiology 1985-07, Vol.8 (4), p.569-573
• Main Authors: LÉVY, SAMUEL, METGE, MARC, COINTE, ROLAND, FAUGERE, GÉRARD, VALEIX, BERNARD, GATAU-PELANCHON, JACQUELINE, GERARD, RAYMOND
• Format: Article
• Language: English
• Subjects: Adolescent; alternate Wenckebach periods; Heart Block - etiology; Humans; Male; retrograde conduction; Tachycardia - complications; ventricular tachycardia
• ISSN: 0147-8389; 1540-8159
• DOI: 10.1111/j.1540-8159.1985.tb05861.x

Although pacing‐induced ventriculo‐atrial (VA) Wenckebach conduction has been previously described, the occurrence of this phenomenon during ventricular tachycardia has received little attention. The latter is defined as 2:1 VA block in which the conducted beats show progressive lengthening of VA conduction until the sequence is terminated by two or three blocked ventricular beats. This phenomenon was observed in a 16‐year‐old boy who underwent electrophysiologic study for ventricular tachycardia as a late complication of surgical correction of tetralogy of Fallot. During pacing‐induced ventricular tachycardia with a morphology similar to that of the spontaneous tachycardia, 8:4 alternating VA block was observed. This sequence suggested that the AV node was the site of block, the 2:1 block being located at the upper level, and the VA Wenckebach block at the lower level Alternate VA Wenckebach conduction appears as a possible cause of variation in atrial depolarization intervals during ventricular tachycardias with short cycle lengths.