A coronary CT angiogram is a test that can check your heart for various conditions, but it's primarily used to check for narrowed arteries in your heart (coronary artery disease) that could explain chest pain or could put you at risk of a heart attack.
Coronary CT angiograms are sometimes used instead of traditional coronary angiograms to check for coronary artery disease. A CT angiogram may be better than a traditional angiogram 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 coronary angiogram. In a coronary angiogram, a catheter is inserted in an artery in your groin and threaded through your blood vessels to your heart. Dye that's visible on X-rays is then injected through the catheter, and X-ray images of your heart are taken.
Your doctor can see blockages and areas of narrowing in your heart's arteries on the images. Because the catheter is near your heart, if blockages are found, your doctor can perform a procedure called angioplasty to open your blockages after a traditional angiogram. However, many people who have coronary angiograms don't have any blockages.
In a CT angiogram, no catheter has to be placed in your groin, and the dye that's visible on the CT scan is injected through an intravenous (IV) line that's placed in your hand or arm. X-ray images are still taken of your heart. However, because no catheter is used, if you need treatment to improve blood flow to the heart, you'll need a separate procedure (a traditional coronary angiogram) to treat your condition.
A test that's similar to CT angiogram is a coronary calcium scan. This test uses a special type of computerized tomography to check for calcium in your coronary arteries, which can be a risk factor for coronary artery disease. No dye is injected during a coronary calcium scan.