The heart muscle needs its own supply of oxygen and nutrients to pump properly. Although its chambers are full of blood, the heart receives no nourishment from this blood. The heart receives its own supply of blood through a network of arteries known as the coronary arteries.
The coronary arteries wrap around the surface of the heart. The two main coronary arteries, the Right Coronary Artery and the Left Coronary Artery, branch off from the aorta.
The heart also includes a system of arteries that branch off of the main coronary arteries that assist in supplying the heart with the needed oxygen and nutrients. The right coronary artery supplies the right atrium and right ventricle. It branches into the posterior descending artery.
The left coronary artery branches into the circumflex artery and the left anterior descending artery. The left coronary artery supplies the left atrium and the left ventricle.
Collateral circulation is a network of tiny blood vessels that usually remain inactive. When coronary arteries narrow to the point that blood flow to the heart is limited, collateral vessels become enlarged and active. This process allows for blood flow around the blocked artery to the heart muscle.
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