What node serves as the backup pacemaker of the heart?

The AV Node, or atrioventricular node, serves as the backup pacemaker of the heart. While the primary pacemaker is the SA Node (sinoatrial node), which initiates electrical impulses that set the heart's rhythm, the AV Node has the important role of taking over if the SA Node fails. It can generate impulses at a slower rate, typically around 40 to 60 beats per minute, which is sufficient to maintain cardiac function if necessary.

The AV Node's location between the atria and the ventricles allows it to serve as a crucial relay point for the electrical signals, ensuring proper timing for the contraction of the heart's chambers. It helps to coordinate the passage of impulses from the atria to the ventricles, allowing for effective heart function. This backup capability is essential for maintaining the heart's rhythm and overall circulatory stability in the event of a malfunction in the primary pacemaking system.