Atrioventricular node Atrioventricular node The atrioventricular node, or AV node is a part of the electrical conduction system of the heart that coordinates the top of the heart. It electrically connects the atria and ventricles. The AV node lies at the lower back section 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). The AV node lies at the lower back section of the interatrial septum near the opening of the coronary sinus, which conducts the
Lunar node about 0.94901 Gregorian year, as do descending-node eclipses. The nodes are called by different names in different areas of the world. In ancient European texts, the ascending node is referred to as the dragon's head ("Caput Draconis", or "Anabibazon"). Its symbol is , the astronomical and astrological symbol for the dragon's head. By the same analogy, the descending node is also known as the dragon's tail ("Cauda Draconis", or "Catabibazon"), and its symbol is the inversion of that of the ascending node: . In Hindu astronomy, the ascending node ☊ is called "Rahu" and the descending node ☋ is called