Right coronary artery arises from the anterior aortic sinus. It runs down along the anterior part of the coronary sulcus, reaches the lower border of heart turns round the lower border and lies in the posterior part of the atrioventricular groove. It ends by anastomosing with the circumflex branch of the left coronary artery. Just before its termination it gives off the posterior interventricular branch that runs downwards, forwards and to the left in the posterior interventricular groove. The branches of the right coronary artery are, branches to SA node, branches to right atrium and right ventricle, right marginal artery, posterior interventricular branches and branches to AV node. It is to be noted that the right coronary artery supplies the right atrium, right ventricle and conducting system of the heart.