Cardiac Computed Tomography (CT) for Calcium Scoring

What is a (CT) Computerized Tomography Coronary Angiogram or CCTA?

The coronary CT angiogram is a test that can check your heart for various conditions but is primarily used to check for narrowed arteries of the heart. Coronary CT angiograms are sometimes used in place of traditional coronary angiograms. A CT angiogram may be better than traditional angiography for people who have only a moderate risk of coronary artery disease.

Typically when your doctor needs to check for blockages in your heart's arteries he or she will perform a traditional coronary angiogram. In a coronary angiogram a catheter is inserted in an artery in the groin and threaded up the blood vessels into your heart. Contrast material is injected through the catheter and x-ray images are taken. Your doctor can see blockages in your heart's arteries on the images. Since the catheter is in place if blockages are found your doctor can perform a procedure called an angioplasty to open the blockages.

In a CT angiogram, no catheter has to be placed in the groin and the contrast visible on the CT images is injected through an intravenous (IV) line placed in your arm. However, because there is no catheter in the groin if blockages are found you will need a separate procedure to treat the blockages.

What is a coronary calcium score?

This test uses computerized tomography (CT) to check for calcium in your coronary arteries which can be a risk factor for coronary artery disease. No contrast is injected for a coronary calcium scan.

Coronary artery disease occurs when plaques build up within the walls of the heart's arteries causing narrowing (atherosclerosis). Coronary calcium scans detect the calcium in those plaques. Added up, the amount of calcium in plaques is used to calculate a score that helps determine your risk of coronary artery disease or heart attack.

If the coronary calcium score scan doesn't reveal calcium in the arteries it doesn't necessarily mean you are free of plaques. Plaques develop calcium only as they mature. The older you get without detectable calcium, the lower your risk of a heart attack or developing coronary artery disease.

What to expect when having a CT coronary angiogram:

At the time of scheduling, you will be asked to:

List your current medications; some may need to be stopped prior to or for a couple of days after the procedure.
List allergies you may have. If you are allergic to the IV contrast used for CT scans, you will need to be pre-medicated for Iodine sensitivity.
Have no caffeine for 12 hours prior to the exam.
Fast for 4 hours prior, sips of water are OK.
Arrive at Patient Registration 1 hour prior to your procedure.

After you check in at Patient Registration:

You will be taken to a (DI) Diagnostic Imaging recovery room and asked to change from the waist up and given a gown.
A nurse will go over some medical history with you and check your vital signs.
An IV will be placed in your arm.
Medications may be given at this time to lower heart rates that are over 59 beats per minute, to improve the quality of the study.

What to expect when you go into the CT room:

The CT technologist will place patches on your chest to monitor your heart that function to synchronize your heart's rhythm to the CT machine.
Your IV will be connected to the contrast media injector.
Breathing instructions will be given prior to the scan.
A small amount of contrast will be injected to determine the timing of your CT cardiac angiogram. You may also be given nitroglycerin spray (vasodilator- increasing blood flow to the heart) under your tongue just prior to injection.
When the contrast is injected, you may feel a warm sensation throughout your body and feel as though you are urinating. This is normal and goes away quickly.
A larger dose of the contrast will be administered for the exam.

When you are finished, you will go back to the DI recovery area and you will be observed for a short time before being discharged.