The right and left coronary arteries supply blood to your heart. They’re the first branches off the aorta, which is the main artery in your body. These arteries and their branches supply all parts of the heart muscle with blood.
The coronary arteries are major blood vessels in your body, supplying blood to your heart. They make it possible for your heart to beat and pump blood throughout your body. You have a right coronary artery (RCA) and a left main coronary artery (LMCA). Each contains smaller branches that go deep inside your heart muscle.
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The function of the coronary arteries and their branches is to supply your heart with blood. Your heart muscles need the oxygen and nutrients in blood so they can pump blood through your heart and the rest of your body.
Your coronary arteries are around and inside your heart muscle. They branch off your aorta, which is the main artery in your body. They start at the aortic root, which is the first part of your aorta that emerges from the left ventricle of your heart. The left ventricle is where oxygenated blood leaves your heart and starts its journey through your body. The coronary artery branches are the first of many branches off your aorta.
There are two coronary arteries, each containing several branches:
It’s important to note that sometimes the structure of the coronary artery branches varies from person to person. Some examples are:
Most of these variations aren’t harmful and don’t produce symptoms. But in rare cases (less than 1% of people) coronary artery abnormalities can lead to serious problems or even death.
The main coronary arteries are usually between 3 and 4 millimeters in diameter. That’s a little smaller than the width of a drinking straw. The sizes of the arteries vary slightly according to your sex, body weight and even ethnicity.
The walls of all arteries, including the coronary arteries, contain three layers:
Coronary artery disease (CAD) is the most common condition that affects your coronary arteries. CAD is often the result of atherosclerosis, which is plaque buildup inside your arteries. Clogged arteries prevent blood from getting to your heart, which can lead to a heart attack.
Acute coronary syndrome is a condition that results in a sudden loss of blood flow to your heart through your coronary arteries. A heart attack is a type of acute coronary syndrome. Like CAD, these conditions are also a result of atherosclerosis.
Less common conditions that affect your coronary arteries include:
Call 911 right away if you experience any of the following symptoms, which could be signs of a heart attack:
A note from Cleveland Clinic
Your coronary arteries carry blood to your heart. They supply your heart muscles with the oxygen and nutrients they need to pump blood through your body. Coronary artery disease (CAD) occurs if these arteries clog and don’t deliver enough blood to your heart. You can reduce your risk of CAD or a heart attack by exercising, eating a healthy diet and not smoking or using tobacco products.
Last reviewed by a Cleveland Clinic medical professional on 05/09/2022.
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