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.
Supplying the Heart With Blood
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.
You may feel:
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.
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.
Doctors will give you treatments for:
When you get angina, doctors will have you take:
Nitroglycerin should work in a few minutes.
To prevent angina, doctors may give you:
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).
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