What is the primary function of the atrioventricular (AV) node?

The primary function of the atrioventricular (AV) node is to regulate the transmission of electrical impulses from the atria to the ventricles. Located between the atria and ventricles, the AV node plays a critical role in the coordinated electrical activity of the heart.

After the sinoatrial (SA) node, which is the natural pacemaker of the heart, generates impulses, the electrical signal travels through the atria, causing them to contract and fill the ventricles with blood. When the signal reaches the AV node, it temporarily delays the impulse before it is transmitted to the ventricles. This delay ensures that the atria have enough time to fully contract and fill the ventricles with blood before the ventricles themselves contract.

By controlling the timing of impulses and allowing for this sequential contraction of the heart chambers, the AV node is essential for maintaining effective and efficient heart function.