The heart is the center of the circulatory system. This pear-shaped organ, slightly larger than a clenched fist, is very powerful. It receives oxygen-rich blood from the lungs and pumps it throughout the body at a rate of more than four quarts a minute.
To keep up with the body’s demands, the heart muscle needs its own healthy blood supply. The main coronary arteries that supply blood to the heart muscle are: the left main coronary artery, which includes the left anterior descending artery and the circumflex artery; and the right coronary artery.
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