Cardiac computed tomography (to-MOG-rah-fee), or cardiac CT, is a painless test that uses an x-ray machine to take clear, detailed pictures of the heart. Doctors use this test to look for heart problems.
During a cardiac CT scan, an x-ray machine will move around your body in a circle. The machine will take a picture of each part of your heart. A computer will put the pictures together to make a three-dimensional (3D) picture of the whole heart.
Sometimes an iodine-based dye (contrast dye) is injected into one of your veins during the scan. The contrast dye highlights your coronary (heart) arteries on the x-ray pictures. This type of CT scan is called a coronary CT angiography (an-je-OG-rah-fee), or CTA.
Doctors use cardiac CT to help detect or evaluate:
Different types of CT scans are used for different purposes. For example, multidetector computed tomography (MDCT) is a fast type of CT scanner. Because the heart is in motion, a fast scanner is able to produce high-quality pictures of the heart. MDCT also might be used to detect calcium in the coronary arteries.
Another type of CT scanner, called electron-beam computed tomography (EBCT), also is used to detect calcium in the coronary arteries.
Because an x-ray machine is used, cardiac CT involves radiation. The amount of radiation used is considered small. Depending on the type of CT scan you have, the amount of radiation is similar to the amount you’re naturally exposed to over
There is a small chance that cardiac CT will cause cancer because of the radiation. The risk is higher in people younger than 40 years old. New cardiac CT methods are available that reduce the amount of radiation used during the test.
Researchers continue to study new and better ways to use cardiac CT.
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