What To Expect Before Cardiac CT

Your doctor will give you instructions before the cardiac computed tomography (CT) scan. Usually he or she will ask you to avoid drinks that contain caffeine before the test. Normally you’ll be able to drink water, but you won’t be able to eat for 4 hours before the scan.

If you take medicines for diabetes, ask your doctor whether you will need to change how you take them on the day of your cardiac CT scan.

Tell your doctor if you:

• Are pregnant or may be pregnant. Even though cardiac CT uses a low radiation dose, you shouldn’t have the scan if you’re pregnant. The x-rays may harm the developing fetus.
• Have asthma or kidney problems or are allergic to any medicines, iodine, and/or shellfish. These may increase your chance of having an allergic reaction to the contrast dye.

A technician will ask you to remove your clothes above the waist and wear a hospital gown. You also will be asked to remove any jewelry from around your neck or chest.

Taking pictures of the heart can be difficult because the heart is always beating (in motion). A slower heart rate will help produce better quality pictures. If you don’t have asthma or heart failure, your doctor may give you a medicine called a beta blocker to help slow your heart rate. The medicine will be given by mouth or injected into a vein.