Wenckebach phenomenon occurring in the distal conducting system in a young adult.

This report describes the case of a young man who presented with right bundle-branch block and second degree atrioventricular block; intermittent episodes of Wenckebach periods were recorded. His bundle electrograms demonstrated progressive prolongation of the HV interval followed by block occurring distal to His. This report emphasizes the fact that the Wenckebach phenomenon as a manifestation of the distal conducting system disease can occur in young adults. The observations lend credence to the concept that Lenègre's disease can occur in young people.