Coronary circulation refers to the specialized set of arteries and veins that supply and drain blood form the heart. The heart does not derive oxygen and nutrients from the oxygenated blood returned by the pulmonary veins to the left atrium. In fact, the heart does not derive any significant exchanges from the blood that passes through any of its four chambers. Because the heart is a dynamic muscular organ, with especially high oxygen demands, the coronary circulation, a specialized sub-circulation of the systemic circulation, ensures delivery of oxygen and nutrients to cardiac tissue as well as the pick-up of carbon dioxide and metabolic waste from cardiac tissue.

Two primary coronary arteries, the right and left coronary arteries, branch from the aorta not far form the juncture of the aorta and the left ventricle. The left coronary artery divides into two major branches, the anterior interventricular branch...