What is the critical role of nodal system in heart?

Also known as the intrinsic conduction system of the heart, it helps the heart beat even when a part of the heart is damaged. However,if one of the 5 parts of the nodal system are damaged, it can cause abnormal heart beat irregularities.

1. sinuatrial node
2. atrioventricular node
3. bundles of his
4. bundle branches
5. purkinje fibers

Irregularities include tachycardia, bradycardia, heart block, fibrillation, arrhythimas.