Atrioventricular node

Atrioventricular Node

The atrioventricular node (or AV node) is a crucial part of the cardiac conduction system. It serves as the electrical bridge between the atria and the ventricles in the heart. The AV node is located in the lower part of the interatrial septum, near the tricuspid valve.

Function

The primary function of the AV node is to delay the electrical signals that pass from the atria to the ventricles. This delay allows the atria to complete their contraction and effectively pump blood into the ventricles before the ventricles start their contraction.

Structure

The AV node is a small mass of specialized cardiac muscle fibers. It is located in the right atrium, near the opening of the coronary sinus. The node is richly innervated by the autonomic nervous system, which modulates its function.

Clinical Significance

Diseases of the AV node, such as AV nodal reentrant tachycardia (AVNRT) and AV block, can disrupt the normal rhythm of the heart and lead to conditions like arrhythmia. Treatment options for these conditions include medication, catheter ablation, and the implantation of a pacemaker.

See Also

• Sinoatrial node
• Bundle of His
• Purkinje fibers