What Are the Risks of Cardiac CT?

Cardiac computed tomography (CT) scans are safe, painless tests. Although cardiac CT uses radiation, the amount is small. This test gives out a radiation dose similar to the amount of radiation you’re naturally exposed to over 3 years. There is a very small chance that cardiac CT will cause cancer.

Some people feel side effects from the contrast dye that’s used during the cardiac CT scan, including the following:

• An itchy feeling or a rash may appear after the injection of the contrast dye. Neither one normally lasts for a long time, so medicine often isn’t needed. If you do want medicine to relieve these symptoms, you can ask your doctor to prescribe you a medicine called an antihistamine, which is used to help stop allergic reactions.
• Although rare, it’s possible to have a serious allergic reaction that may lead to breathing difficulties. Medicines are used to treat serious reactions.

People who have asthma or emphysema may have breathing problems during cardiac CT if they’re given beta blockers to slow down their heart rates.