Relating to both the atria (chambers) and the ventricles of the heart, especially to a connecting conduction event or anatomic structure between the atria and ventricles; a chamber of the heart that receives blood from an atrium (heart chamber) and pumps it to the arteries: The atrioventricular sections of the heart include the upper chambers of he heart (atria) and the lower chamber of the heart (ventricles).

The electrical relay station between the upper and lower chambers of the heart: "Electrical signals from the atria (upper chambers) must pass through the atrioventricular node in order to reach the ventricles (two lower chambers of the heart)."

"The atrioventricular note, or AV node, which controls the heart rate, is one of the major elements in the cardiac conduction system (specialized tissue that carries bodily electrical impulses)."