Wenckebach's periods or alternating Wenckebach's periods during 4:1 atrioventricular block?

摘要

This article deals with the tracings of a patient having episodes of atrial flutter with 4:1 atrioventricular (AV) block increasing to 8:1 AV block. This phenomenon was attributed to the coexistence of 3-level block due to transverse dissociation with 2:1 AV block in the most proximal level, or first level as well as in the second level coexisting with a Wenckebach's period in the most distal, or third level. It is suggested that perhaps the term Wenckebach's periods during progression of 4:1 AV block best describes this arrhythmia so as to maintain the term alternating Wenckebach's periods only to those occurring when 2:1 block increases to higher degrees of AV block.