What happens in the last step of the conduction system?

In the last step of the cardiac conduction system, the ventricles contract. This occurs after the electrical impulse generated by the sinoatrial (SA) node travels through the conduction pathways, causing the atria to contract first, and then reaching the atrioventricular (AV) node. After a brief delay at the AV node to allow for filling of the ventricles, the impulse moves down through the bundle of His and into the Purkinje fibers, leading to a coordinated contraction of both ventricles. This contraction is essential for pumping blood either to the lungs or to the rest of the body, facilitating proper circulation.

Understanding this step is critical for grasping how electrical activity translates into mechanical action in the heart, which is vital for maintaining effective blood flow and overall cardiovascular health.