CT coronary angiogram

Overview

A computerized tomography (CT) coronary angiogram is an imaging test that looks at the arteries that supply blood to the heart. A CT coronary angiogram uses a powerful X-ray machine to make images of the heart and its blood vessels. The test is used to diagnose many different heart conditions.

A CT coronary angiogram involves no surgical cuts in the body. It is different from a standard coronary angiogram. With a standard coronary angiogram, a doctor makes a small cut in the groin or wrist. A soft tube called a catheter is then guided to the heart arteries.

A CT coronary angiogram also may be called a cardiac CT angiography (CCTA) scan. It is not the same test as a CT coronary calcium scan. A CT coronary angiogram looks for a buildup of plaque and other substances in the coronary artery walls. A CT coronary calcium scan looks only at how much calcium is in the artery walls.

Why it's done

A CT coronary angiogram mainly is done to check for narrowed or blocked arteries in the heart. It may be done if you have symptoms of coronary artery disease such as chest pain. But the test can look for other heart conditions too.

Risks

A CT coronary angiogram uses radiation. The amount depends on the type of machine used. If you are pregnant or think you may be pregnant, you ideally should not have a CT angiogram. Radiation from the test may harm the unborn child, also called a fetus. But some people with serious health conditions may need CT imaging during pregnancy. A healthcare professional takes steps to limit radiation exposure to the unborn child during the test.

A CT coronary angiogram is done with a substance called contrast. It can get into breast milk, so tell your healthcare professional if you're breastfeeding. Your team may give you suggestions on how to prepare before your test.

Some people also have an allergic reaction to contrast. Talk with your healthcare professional if you're concerned about this risk. If you have a contrast allergy, you may be asked to take steroid medicine 12 hours before the test. This lowers your risk of a reaction.

Rarely, contrast may damage the kidneys, especially in people with chronic kidney disease.

How you prepare

A healthcare professional tells you how to prepare for a CT coronary angiogram. Driving yourself to and from the test should be OK.

Food and medicines

You may be told not to eat anything for at least eight hours before a CT coronary angiogram. Drinking water is OK. Don't have drinks that contain caffeine for 12 hours before the test. Caffeine can raise the heart rate and make it harder to get clear pictures of the heart.

Tell your healthcare team about the medicines that you take. You may be asked not to take some medicines before the test.

Clothing and personal items

For the test, you need to remove jewelry, glasses and clothing above the waist. You change into a hospital gown.

What you can expect

A CT coronary angiogram usually is done in the radiology department of a hospital or an outpatient imaging facility.

Before

Before a CT coronary angiogram, a healthcare professional may give you medicine called a beta blocker. This medicine slows your heart rate to help the CT scanner make clearer images. Tell your healthcare professional if you've had side effects from a beta blocker in the past.

You also may be given a medicine called nitroglycerin to widen your coronary arteries. This helps them appear more clearly in the images taken during the test.

During

A healthcare professional places a thin tube called an IV into your hand or arm. A substance called contrast flows through this IV. The contrast helps blood vessels show up better on the images taken during the test. Sticky patches with sensors on them go on your chest to record your heart rate.

You lie on a long table that slides through a short, tunnel-shaped machine called a CT scanner. If you're not comfortable in closed spaces, ask your healthcare professional about medicine to help you relax. Do this before the day of your test.

During the scan you need to stay still and hold your breath as told. Movement can cause blurry images.

A healthcare professional controls the CT machine from a separate room with a glass window. An intercom system lets you talk with the healthcare professional during the test.

The scanning part of the test takes just a couple of seconds. But the entire process may take up to an hour if you're given medicines such as beta blockers or nitroglycerin.

After

After a CT coronary angiogram, you typically can return to your daily activities. You likely can drive after the test if there are no complications. Drink plenty of water to help flush the contrast from your body.

Results

The images from your CT coronary angiogram should be ready soon after your test. The healthcare professional who asked you to have the test gives you the results.

If your test suggests that you have or are at risk of heart disease, you and your healthcare professional can talk about treatment options.

Regardless of the test results, it's always a good idea to make lifestyle changes to help protect the heart. Try these heart-healthy habits:

• Get regular exercise and stay active. Staying active keeps the heart healthy. Exercise at least 30 minutes a day on most days of the week. Try walking, biking, swimming or even mowing the lawn. But ask your healthcare team what's right for you.
• Eat healthy foods. Eat plenty of fruits, vegetables and whole grains. Eat less sugar, salt, and saturated and trans fats. A healthy diet can help manage weight, blood pressure, cholesterol and blood sugar.
• Keep a healthy weight. Being at a healthy weight and staying there is good for your heart. If you are overweight, losing even a small amount of weight can help reduce risk factors for coronary artery disease. Ask your healthcare professional what weight is right for you.
• Don't smoke or use tobacco. Smoking is a major risk factor for coronary artery disease. Nicotine tightens blood vessels and forces the heart to work harder. Not smoking is one of the best ways to lower the risk of a heart attack. If you need help quitting, talk with your healthcare professional.
• Manage health conditions. Ask your healthcare professional how often you need to have your blood pressure, blood sugar and cholesterol levels checked.
• Lower stress. Stress can cause blood vessels to tighten. This raises the risk of a heart attack. Some ways to ease stress are to get more exercise, practice mindfulness and connect with others in support groups.
• Get enough sleep. Adults should try to get 7 to 9 hours of sleep a night.

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