Bundle of His — ECG/EKG Terminology

Definition: Specialized muscle fibers that carry electrical impulses from the AV node down through the septum toward the ventricles.

Key Facts

• The Bundle of His is the only normal electrical bridge from atria to ventricles.
• Transmits impulses rapidly from AV node into bundle branches.
• Conduction delay below AV node can widen QRS and create escape rhythms.

ECG Connection: Infra-Hisian conduction delay may present with PR prolongation, dropped beats, or wide-complex bradycardia.

Why It Matters: Localization of block level helps communicate urgency and escalation needs.