Innovative technology is at the heart of new advances in cardiovascular care - and the improved results they bring. One of these, computed tomography (CT) angiography, uses advanced imaging capabilities to look inside your body and see how blood flows from arteries in the heart to the brain, lungs, kidneys, arms, legs and other areas. This allows doctors to precisely identify and treat problems.
Here's how it works:
X-ray beams capture cross-sectional images o an area of the body; a computer then combines them into a three-dimensional picture. These highly detailed images allow doctors to detect and diagnose problems so they can treat them in the most effective manner.
Putting it to the test
CT angiography offers a number of benefits. It is typically performed as an outpatient procedure and is less invasive, quicker, safer and more patient friendly than catheter angiography, which is the standard diagnostic tool. In addition, it displays images of blood vessels more precisely than magnetic resonance imaging (MRI) or ultrasound. The test is a valuable tool that doctors most commonly use to:
- Examine the arteries that travel to the lungs, heart, kidneys, pelvis, legs and the neck to check for blockages and other problems.
- Identify aneurysms in the aorta, brain or other major blood vessels. Aneurysms are severely weakened areas of the blood vessel wall that bulge out. If they rupture, the consequences are often fatal.
- Identify dissection in the aorta, a serious condition in which the layers of the artery wall peel away from each other.
- Check functioning of a stent, a mesh tube used to restore blood flow to a blocked artery.
A Step-by-Step Guide to Your Exam
Getting Ready - here are a few things to expect:
- You may be asked to only drink clear liquids before your CT angiography.
- When you arrive for your test, you will be asked if you have asthma or allergies to foods or drugs, and what medications you are taking. If you are breastfeeding, inform the technologist before the procedure.
- You may not need to undress if you are having an exam of the head, neck, arms or legs, but you will have to remove any jewelry or dentures. Prior to the exam, women will be asked to remove a bra with metal underwires; however, you will not have to remove a sports bra.
During your CT Angiogram
At the start of your exam, the area of your body being studied will be positioned inside the opening of the CT unit and a test image taken.
Next, contrast material (a type of dye) will be injected through a vein in the arm to make the blood vessels stand out. A machine automatically injects the contrast at a controlled rate. You may experience a feeling of warmth, but the test should not be painful at any time.
A rotating device spins by you, creating a beam of X-rays. A detector takes pictures of the beam as it passes by. Since the scanner is "open," only a small part of your body will be inside at one time. The table will move in and out of the scanner opening. You will be asked to remain still on the table, as any movement can affect the results of your test. You may be asked to hold your breath for 10-25 seconds so the pictures do not blur.
Finally, the images will be reviewed and, if needed, some will be repeated. While the test itself takes about 10-25 minutes, your entire visit can take up to one hour.
About your results
The cardiologist will report findings to your physician, who will discuss them with you. Results of the CT angiogram are usually available within 24 hours. However, in complicated cases, it may take longer.
A word of caution:
- Some people are allergic to the iodine in the contrast material. If you have a history of this type of allergy, you may be given special medication before hand to lessen risk. Or you may opt to undergo another type of exam.The contrast material can cause problems for patients with kidney disease or severe diabetes.
- If a large amount of the contrast material leaks from the N the surrounding skin can be damaged. Report any pain at the site of the injection immediately.
- Pregnant women, especially those in the first three months, should not have CTA or any exam exposing them to X-rays.