Cardiac computed tomography angiography (CT, CTA or CCTA) is a non-invasive diagnostic image that produces 3-D images of your heart and associated blood vessels. The images allow doctors to see the heart vessels without actually going inside your heart.
Cardiac CT is used for:
- Identifying calcium (plaque) buildup in blood vessels to the heart.
- Spotting possible narrowing of the blood vessels in and around the heart.
- Identifying aneurysms in major blood vessels or dissections in the aorta. Aneurysms are weakened areas of the blood-vessel walls that bulge out. Dissections are layers of artery wall that peel away from each other, weakening the artery.
- Diagnosing coronary-artery disease and heart disease at an early stage.
How does a cardiac CT scan work?
The special, doughnut-shaped x-ray machine emits radiation beams from several different angles to create three-dimensional cross-sectioned images of your heart and surrounding blood vessels. Contrast material is injected into a small vein in your arm and tracked by the cardiac CT scan as the contrast moves with the blood flow into the heart. The scanner collects information that is used to create hundreds of pictures of your heart. A computer allows the doctor to see your heart in multiple views.
Preparing for your cardiac CT scan
- Avoid any food or drinks with caffeine the day of your exam.
- Do not smoke.
- Avoid taking energy or diet pills on the before and day of the exam.
- Do not eat or drink anything four hours before the exam.
- Do not use Viagra or any similar medication on the day before or day of the exam. It is not compatible with the medications you will receive.
- If you take diabetes medicine or injections, the radiology nurse will give you special instructions.
- If you take other medications, please take your regular dose at your regular time.
- Arrive one hour before the exam.
- Please have someone to drive you home.
What to expect during a cardiac CT scan
- The nurse will start an IV in your arm and begin to monitor your vital signs.
- If needed, you will be given medication to lower your heart rate and make your pictures clearer. It may take an hour or more for the medication to take effect.
- When you have the appropriate heart rate, you will be taken into the CT scan room and placed on a heart monitor while lying on the scan table.
- Two scans will be taken: one before the contrast is injected through your IV, and one after. The scan without the contrast allows the doctor to see calcium deposits. The one with the contrast allows the doctor to see narrowing within heart vessels. You will be asked to hold your breath for 5–10 seconds each time.
- The IV contrast that is injected into your arm may give you a warm, flushed feeling for a few seconds as the CT scan table moves you in and out of the scanner.
- After your cardiac CT scan
- A radiologist will review your scan and send the final results to the doctor who ordered the scan. Please tell the receptionist if any other doctors need to receive the results of your scan.