Which part of the heart's electrical conduction system is responsible for initiating electrical impulses?

The Sinoatrial (SA) node is recognized as the primary pacemaker of the heart. It is a group of specialized cells located in the right atrium and is responsible for initiating electrical impulses that trigger each heartbeat. These electrical signals cause the atria to contract, pumping blood into the ventricles and setting the rhythm for the heart.

This function of the SA node is crucial because it regulates the heart rate and coordinates the timing of the heart's contractions. The inherent rhythmicity of the SA node allows it to autonomously generate impulses, which effectively beats even without external stimulation. The other components of the heart's electrical conduction system, such as the atrioventricular node, the Bundle of His, and the Purkinje fibers, play roles in conducting these impulses or coordinating contractions but do not initiate them. Therefore, the Sinoatrial node is fundamentally vital for the heartbeat and heart rhythm.