Question

Describe the anatomical pathway of the conducting system of the heart.

Note: Please type or write answers neatly and legibly.

Thank you for your time.

Answer 1

Conduction Pathway of the Heart

It consists of
1. Sinatrial node (SA node)
2. Atrial Ventricular Node (AV Node)
3. Bundle of Hiss or AV bundle
4. Right and Left bundle branches
5. Purkinjie Fibers.

1. SA Node

It is composed of special cardiac cells and nerve fibers and is located in the upper portion of the right atrium in the superior posterior wall of the right atrium.

2. AV Node or AV Ventricular Node

It is located on the floor of the right atrium at the beginning of the inter ventricular septum.
It causes a delay in the transmission of electrical impulses from the atria to the ventricles for the following reasons.
To give both the atria enough time to empty all the blood before they relax.
To protect the ventricles from the fast heart rate of the atria.
It fires electrical impulses at the rate of 40 to 60 per minute.
The AV node transfers impulses from the atria to the ventricles.

3. Bundles of Hiss or A.V Bundle

It is located next to the AV Node.

4. Bundle Branches

The right and left bundle branches run along either side of the interventicular septum.

5. Purkinjie Fibers

They transmit electrical impulses to the myocardial walls of the ventricles.
They fire at the rate of 20 to 30 beats per minute.