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Last full review/revision Sep 2019| Content last modified Sep 2019
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What is angina?

Angina is pain, discomfort, or pressure in your chest that happens when your heart isn't getting enough oxygen. The lack of oxygen is caused by a narrow or blocked artery to your heart (coronary artery disease). Angina is often a warning sign of a heart attack.

  • Go to the hospital right away if you have pain, pressure, or burning in your chest, back, shoulders, jaw, or arms

  • Angina happens when you're exerting yourself and gets better quickly when you rest

  • Doctors usually do an ECG/EKG and a stress test or cardiac catheterization

  • Treatment is with medicines or sometimes a procedure such as angioplasty or bypass surgery

Supplying the Heart With Blood

Like any other tissue in the body, the muscle of the heart must receive oxygen-rich blood and have waste products removed by the blood. The right coronary artery and the left coronary artery, which branch off the aorta just after it leaves the heart, deliver oxygen-rich blood to the heart muscle. The right coronary artery branches into the marginal artery and the posterior interventricular artery, located on the back surface of the heart. The left coronary artery (typically called the left main coronary artery) branches into the circumflex and the left anterior descending artery. The cardiac veins collect blood containing waste products from the heart muscle and empty it into a large vein on the back surface of the heart called the coronary sinus, which returns the blood to the right atrium.

Supplying the Heart With Blood

What causes angina?

The most common cause of angina is narrowing of the arteries that carry blood to your heart (coronary arteries). That narrowing is most often caused by atherosclerosis, commonly known as hardening of the arteries. A fatty deposit builds up and can slowly block your arteries and slow down or stop the flow of blood. When your heart muscle doesn't get enough blood, it hurts.

Angina can also be caused by a coronary artery spasm, a sudden tightening of the artery. Certain drugs such as cocaine may trigger a spasm.

Severe anemia (low blood count) increases your risk of having angina. With anemia, you have fewer red blood cells to carry oxygen.

What are the symptoms of angina?

You may feel:

  • Discomfort, pressure, or aching in the middle of your chest

  • The discomfort may travel to your shoulder, down your arm, or to your throat, jaw, or teeth

Angina usually comes when you exert yourself, for example, by climbing stairs or walking up a hill. It goes away in a few minutes when you rest. You usually get angina each time you do the same amount of exertion. For example, you may get angina every time you walk up a certain hill. As your coronary arteries get narrower, you get angina with less and less exertion. For example, if you first got angina climbing 2 fights of stairs, later you might get it with only 1 flight of stairs.

Angina that comes without any exertion or that gets worse very quickly is:

Unstable angina is a warning you might be about to have a heart attack.

How can doctors tell if I have angina?

If you have symptoms that suggest angina, doctors will do tests such as:

  • Stress test—a test to see whether your heart is getting enough blood when it works hard (is under stress), such as when you exercise

  • ECG/EKG—a test that measures your heart’s electrical activity, which can be abnormal in coronary artery disease

  • CT scan—an imaging test to look for hardening of the coronary arteries

If your angina is severe or getting worse, doctors may do:

  • Cardiac catheterization—an invasive test that allows doctors to see if and where your coronary arteries are blocked

In cardiac catheterization, doctors put a long, thin catheter (small flexible tube) into an artery in your arm or leg, up to your heart, and into each of your coronary arteries.

How do doctors treat angina?

Doctors will give you treatments for:

  • When you get angina

  • Preventing angina

  • The problem that's causing your angina

When you get angina, doctors will have you take:

  • Nitroglycerin tablets or spray under your tongue

Nitroglycerin should work in a few minutes.

To prevent angina, doctors may give you:

  • Long-acting nitroglycerin pills or skin patches

  • Medicines to keep your heart from working too hard

To treat the problem that's causing your angina, doctors usually give you:

They will also have you change any behaviors that are hurting your heart, such as smoking, not exercising, and eating a poor diet.

Depending on how much your coronary arteries are blocked, doctors may do a procedure to clear your artery. They may do angioplasty or bypass surgery (also called coronary artery bypass grafting or coronary artery bypass surgery).

During angioplasty:

  • The doctor puts a small, flexible tube (catheter) into an artery in your upper leg (groin) or in your wrist

  • The catheter is pushed up the artery to your heart and then into one of your coronary arteries

  • A small balloon on the tip of the catheter is inflated

  • The balloon pushes the blockage open

  • Then the doctor slips a wire mesh tube (stent) off the end of the catheter into the blocked area

  • The wire mesh tube helps hold the blocked area open

During bypass surgery:

  • Doctors take a piece of healthy artery or vein from another part of your body

  • They sew one end of that piece of artery or vein to your aorta (the major artery that takes blood from your heart to the rest of your body)

  • They sew the other end to your blocked artery past the point of the blockage

  • Your blood then flows through this new route, bypassing the blockage

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