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The coronary arteries deliver blood to the heart muscle, providing a
continuous supply of oxygen and nutrients needed for it to stay healthy and
The coronary arteries regulate the supply of blood to your heart
muscle depending on how much oxygen your heart needs at the time, as indicated
The harder the heart has to work to pump blood, the more oxygen it
needs. For example, when you exercise, your heart rate and blood pressure
increase, which in turn increases your heart's demand for oxygen.
The main way to increase the oxygen supply to the heart is to
increase the blood flow through the coronary arteries. Your heart increases the
blood flow by widening (dilating) your coronary arteries.
If your coronary arteries aren't able to dilate properly, your
heart muscle may not be able to get the amount of oxygen it needs to function
Your left ventricle pumps blood into the main artery of your body,
called the aorta. See a picture of the
heart and coronary arteries. Close to the heart, the two main coronary arteries
branch off of your aorta.
The coronary arteries also include the collateral coronary
arteries, small blood vessels that connect the normal coronary arteries with
one another. When the heart is healthy, these vessels play only a minor role.
When a coronary artery becomes obstructed, though, collateral coronary
arteries help increase the flow of blood to the area of the heart that is being
deprived of blood flow. These vessels, although small, may actually succeed in
providing sufficient blood to help prevent major damage to the heart muscle
during a heart attack.
When the heart doesn't get enough oxygen-rich blood through the
coronary arteries, the affected heart muscle can weaken or die. This is what
happens during a heart attack. The damaged heart muscle cannot pump
effectively, leading to heart failure.
ByHealthwise StaffPrimary Medical ReviewerRakesh K. Pai, MD, FACC - Cardiology, ElectrophysiologySpecialist Medical ReviewerRobert A. Kloner, MD, PhD - Cardiology
Current as ofJanuary 27, 2016
Current as of:
January 27, 2016
Rakesh K. Pai, MD, FACC - Cardiology, Electrophysiology & Robert A. Kloner, MD, PhD - Cardiology
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