A case of infra-nodal Wenckebach conduction block with alternating bundle branch block

International Journal of Arrhythmia

Chun Hwang¹  Pichmanil Khmao²  Hui-Nam Pak² 

[1] Department of Cardiology, Revere Health, Provo, UT, USA;Yonsei University Health System, 50-1 Yonsei-ro, Seodaemun-gu, 03722, Seoul, Republic of Korea;

关键词: Ashman phenomenon;    Atrioventricular node;    Bundle branch block;    His-Purkinje system;    Infra-nodal block;   

DOI  :  10.1186/s42444-021-00036-w

来源: Springer

【 摘 要 】

BackgroundAtrioventricular (AV) node normally has decremental conduction property and a longer refractory period than His-Purkinje system (HPS). This results in AV conduction delay or block at the level of AV node in response to short-coupled atrial premature beats. Prolonged refractoriness in HPS can produce unusual physiological patterns of AV conduction such as conduction delay or infra-nodal block in the distal elements of HPS.Case presentationWe present a case in which atrial premature stimulation produces infra-nodal Wenckebach conduction block which initiates long-short cycle sequence within the bundle branches resulted in alternating bundle branch block and atypical pattern of Ashman phenomenon.ConclusionsThis case highlights the importance of recognizing the unusual physiological AV conduction patterns of HPS. The long-short cycle sequence in the bundle branches of distal HPS and linking phenomenon can result in alternating bundle branch block without the presence of HPS disease.

【 授权许可】

CC BY