What is "atrioventricular node"

n. a node of specialized heart muscle located in the septal wall of the right atrium; receives impulses from the sinoatrial node and transmits them to atrioventricular bundle

The atrioventricular (AV) node is a part of the electrical conduction system of the heart that coordinates the top of the heart. It electrically connects atrial and ventricular chambers. The AV node is an area of specialized tissue between the atria and the ventricles of the heart, specifically in the posteroinferior region of the interatrial septum near the opening of the coronary sinus, which conducts the normal electrical impulse from the atria to the ventricles. The AV node is quite compact (~1 x 3 x 5 mm). It is located at the center of Koch's triangle—a triangle enclosed by the septal leaflet of the tricuspid valve, the coronary sinus, and the membraneous part of the interatrial septum.