EKG artifact

(Click on the image to enlarge)
This would have been reported as tachycardia if Channel III was not available! (Not sure what the reason for this artifact is. Recording was auto-triggered by the event monitor. Patient does not know; was probably sleeping).


Conduction system in VSD

Course of His bundle in VSD: Figure below shows the relationship for membranous VSD and inlet-muscular VSD (Note: Inlet-muscular VSD is different from inlet-VSD in AVSD.

Inlet-muscular VSD has a rim of myocardium separating the VSD margin from the tricuspid valve annulus; whereas, in inlet-VSD in AVSD, AV valve annulus itself if part of the VSD margin.
(See also separate posting for relevant images).

Image from Anderson RH, Wilcox BR. J Card Surgery. 1992;7:17-34.