Intra‐Atrial Conduction Block Along the Mitral Valve Annulus During Accessory Pathway Ablation: Evidence for a Left Atrial “Isthmus”

Abstract

An isthmus of conductive tissue is present in the low lateral left atrium of some individuals. Awareness of this structure may avoid misinterpretation of the electrogram during left AP ablation and may be useful in future therapies of atypical atrial flutter and fibrillation.