What is the name of the original pacemaker of the heart?

The sinoatrial node is known as the natural pacemaker of the heart because it generates electrical impulses that initiate each heartbeat. Located in the right atrium, this cluster of cells is responsible for setting the rhythm and rate of the heartbeat, effectively controlling the timing of contractions in both the atria and the ventricles.

The sinoatrial node works by spontaneously depolarizing, meaning it can generate an action potential without external stimulation. This impulse spreads through the atrial myocardium, leading to the coordinated contraction of the atria. Following the atrial contraction, the electrical impulse travels to the atrioventricular node and further into the conduction system, ensuring the ventricles contract in a synchronized manner after the atria.

In contrast, while the atrioventricular node, the bundle of His, and Purkinje fibers have important roles in the conduction system of the heart, they do not initiate the heartbeat. The atrioventricular node acts as a relay station and introduces a delay to allow for proper filling of the ventricles, while the bundle of His and Purkinje fibers conduct impulses throughout the ventricles to facilitate their contraction. Thus, the sinoatrial node remains the primary driver of the heart's rhythmic activity.