A coronary angiogram is an X-ray test that takes pictures of the blood flow through your coronary arteries. It helps your doctor see if your arteries are clogged, where they are clogged, and by how much. An angiogram helps you and your doctor decide what treatment is best for your coronary artery disease. Treatments include medicines, angioplasty, and coronary artery bypass surgery.

During an angiogram, a thin tube called a catheter is placed in an artery of your arm or leg and gently threaded up into your heart. A special dye goes through the catheter. The dye helps the arteries show up on the X-ray. The doctor checks the X-rays to see if your coronary arteries are clogged or blocked.

Coronary artery disease occurs when fatty deposits called plaque (say "plak") build up inside the coronary arteries. The coronary arteries wrap around the heart and supply it with blood and oxygen. When plaque builds up, it narrows the arteries and limits how much blood can get to your heart.

Coronary artery disease can occur slowly over time without your knowing it. You may not have any symptoms until the arteries are very narrow. Symptoms include chest pain (angina) and shortness of breath.

Without treatment, coronary artery disease can lead to serious problems, such as a heart attack or a stroke.

Your doctor is likely to suggest that you adopt healthy habits such as quitting smoking, eating a heart-healthy diet, and getting regular exercise. By doing these things, you can slow the spread of the disease and improve your quality of life.

You may need to take medicines to lower your cholesterol or high blood pressure. Your doctor may prescribe aspirin to reduce your risk of heart attack. And he or she may prescribe other medicines to control chest pain (angina), if you have it.

If lifestyle changes and medicines don't work well enough to relieve your symptoms and lower your risk for a heart attack, you may need to have angioplasty or bypass surgery.

If during the angiogram the doctor sees that your arteries are badly blocked, you may need angioplasty or bypass surgery right away. You may want to talk with your doctor about these treatments before you have an angiogram. During the test, you will not be able to decide about more treatment, because you will be sleepy from medicines.

Your doctor may suggest that you have this test if:

• A cardiac stress test suggests that you have severe heart disease. This test checks for changes in your heart while you exercise.
• You have chest pain (angina) while you are at rest or during only moderate physical activity. Or you are taking medicines for chest pain but they don't control it.
• You have another heart problem, such as heart failure, that may be caused by heart disease.

You probably do not need an angiogram if you can control your angina and other symptoms with medicines and lifestyle changes and if you are otherwise healthy.