Because the heart is a muscle that works continuously to feed oxygenated blood to the body, it needs its own supply of oxygen-rich blood to power its contractions. The heart receives its blood supply through vessels called coronary arteries arising from the base of the main artery to the body, the aorta.
Fatty deposits in the linings of the coronary arteries can narrow the channel and limit the amount of blood and oxygen reaching the heart muscle. This restriction of blood flow to the heart is a condition called atherosclerosis.
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