A computed tomography angiogram (CT angiogram) is a test that uses X-rays to provide detailed pictures of the heart and the blood vessels that go to the heart, lung, brain, kidneys, head, neck, legs, and arms.

A CT angiogram can show whether a blood vessel is blocked, where the blockage is, and how big the blockage is. The test can also show whether there is a bulge (aneurysm) or a buildup of fatty material called plaque in a blood vessel.

During a CT angiogram, you lie on a table that passes through a doughnut-shaped opening in the scanner. A special dye (contrast material) is put in a vein (IV) in your arm or hand to make the blood vessels easier to see on the scan. If you are having a CT angiogram to look at your heart and the blood vessels that go to it (coronary arteries), you may be given a medicine called a beta-blocker to slow your heart rate during the test.

Why It Is Done

A CT angiogram is done to look for:

• A narrowing (stenosis) or blockage in the coronary arteries. This can occur when there is a buildup of fat (cholesterol) and calcium in the arteries. This buildup is called plaque.
• Heart problems, such as pericarditis (a buildup of fluid around the heart) and damage or injury to the heart valves.
• A bulge (aneurysm) or tear (dissection) in the aorta, which is a large blood vessel that carries blood from the heart to the rest of the body.
• A blood clot in the lungs (pulmonary embolism).
• A narrowing of the veins in the leg (deep vein thrombosis).
• An abnormal pattern of blood vessels that may be a sign of a tumor.

A CT angiogram is a less invasive test than a standard angiogram. A standard angiogram involves threading a thin tube called a catheter through an artery in your arm or leg up to the area being studied. But with a CT angiogram, no tubes are put in your body. For more information, see the medical test Angiogram.