Aorta
The aorta ( ) is the main artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta distributes oxygenated blood to all parts of the body through the systemic circulation.
Atrioventricular nodal branch
The atrioventricular nodal branch is a cardiac artery that is crucial because it feeds the atrioventricular node, necessary for the excitation and contraction of the ventricles. Most frequently (in over 80% of humans) it arises as a distal branch from the right coronary artery near the crux of the heart. In some people, the atrioventricular node instead receives blood from the circumflex branch of the left coronary artery, otherwise known as the left circumflex coronary artery or LCX. Very rarely, in approximately 2% of people, the vascular supply to the atrioventricular node arises from both the right coronary artery and the left circumflex branch.