Computed Tomography (CT)

Computed tomography, sometimes called a CT scan or a CAT scan, is an advanced type of x-ray that can be used to measure calcium and find blockages, or plaques, in the coronary arteries. In some cases, you may be given a dye called a contrast agent that will help produce clearer pictures of your heart and its blood vessels. There are 2 types of CT scans used to detect coronary artery disease.

• Electron-beam computed tomography (EBCT), sometimes called an ultrafast CT or a heart scan, measures the levels of coronary calcium, a sign of CHD. While you lie on a special x-ray table, electron beams scan your heart to produce a picture of areas in the coronary blood vessels where calcium has built up over time.
• Multislice or multidetector computed tomography (MSCT or MDCT) uses a doughnut-shaped x-ray machine that moves rapidly around your body as you lie on a special table. As it moves, it takes several pictures at different angles to create a detailed map of your heart and coronary arteries. Like EBCT, MSCT can identify and measure coronary calcium deposits, but the very clear pictures it produces also allow detection of very small plaques that may be blocking blood flow to your heart but are missed by other tests.
   

CT is often used to detect early signs of CHD in women with risk factors or symptoms of heart disease. It may help your healthcare provider decide whether you need to undergo other tests or procedures, or if you should start taking medicines to prevent a heart attack.

Since CT scans expose you to a small amount of radiation, tell your healthcare provider if you think you might be pregnant before taking these tests.