When discussing the AV node's role in the electrical conduction of the heart with a client newly diagnosed with an AV block, which of the following statements are accurate? Select all that apply

Question

A) The AV node offers a two-way conduction area between the atria and the ventricles.
B) The velocity of conduction through the AV junctional fibers is very fast, which greatly increases impulse transmission.
C) A block at the AV bundle of His interferes with the normal delay of the impulse, thereby interfering with complete ejection of blood from the atria prior to ventricular contraction.
D) When there is an AV block, impulses from the atria and ventricles beat independently of each other so, the heart rhythm is usually chaotic and not regular.

Answer 1

Ans: C, D
Feedback:
The AV node connects the atrial and ventricular systems and normally provides for a one-way conduction between the atria and ventricles. The velocity of conduction through the AV junctional fibers is very slow, which greatly delays impulse transmission. A further delay occurs as the impulse travels through the transitional fibers and into the AV bundle, known as the bundle of His. This delay provides a mechanical advantage whereby the atria can complete their ejection of blood before ventricular contraction begins. Under normal circumstances, the AV node provides the only connection between the atrial and ventricular conduction systems. The atria and ventricles would beat independently of each other if the transmission of impulses through the AV node were blocked.