Coronary Blood Vessels

The heart muscle itself needs a private blood supply to bring it nutrients and oxygen and remove its waste, and that supply is delivered by the coronary arteries and drained by the coronary veins. There are two coronary arteries, right and left, and both are the very first branches to come off the aorta - they wrap around the heart in a pattern resembling a crown, which is exactly where the name comes from (Latin corona, 'crown'). The right coronary artery supplies the right ventricle and the posterior part of the left ventricle, while the left coronary artery supplies the anterior and lateral parts of the left ventricle. This is why a blockage in a coronary artery is so dangerous: it starves a specific, predictable region of heart muscle of oxygen, which is the direct cause of a heart attack (covered later in the chapter's disorders section). The heart's demand on its coronary supply is not constant - during vigorous exercise the body actively reroutes blood away from the digestive organs toward the …