node (A-V node): A group of specialized cells that receive impulses from the atria of the heart and pass the impulses to the ventricles, causing them to contract. The A-V node also acts like a gate, preventing the ventricles from beating too fast when there is an abnormal rhythm in the atria, such as in atrial fibrillation. Back to Previous Page
node It is the small mass of conduction tissue, located between the upper and lower chambers of the heart, through which electrical impulses pass, controlling heart rhythm pass.