A CT aortogram (or CT angiography of the aorta) is a rapid, highly detailed scan used to check the aorta, which is the largest blood vessel in your body. The aorta carries blood from your heart down through your chest and abdomen to feed the rest of your organs.
If you present with severe, sudden chest or back pain, a CT aortogram is used to check for life-threatening issues, such as a bulging artery (aneurysm) or a tear in the blood vessel wall (aortic dissection).
Common Indications for a CT Aortogram
- Investigating sudden, tearing chest or back pain.
- Screening for or monitoring a known abdominal or thoracic aortic aneurysm.
- Evaluating a suspected tear (dissection) or blockage in the aorta.
- Checking for injuries to the aorta after a major accident or trauma.
- Planning surgeries or stent placements on the aorta.
What exactly does a CT aortogram show?
The scan shows a three-dimensional view of the entire path of your aorta. By using contrast dye, it highlights the thickness of the blood vessel walls, the size of any bulges, and any narrow areas or blockages.
How should I prepare for a CT aortogram?
Fasting and fluid instructions vary by centre, urgency, and whether sedation is planned. Follow the appointment instructions. Do not deliberately overdrink; tell the team if you have heart failure, kidney disease, or a fluid restriction.
Do I need to stop taking medication?
Do not stop medication unless the clinical team tells you to. Metformin is not routinely withheld after every intravenous contrast CT; the decision depends on kidney function, acute kidney injury, and local policy. Confirm the instructions for your situation.
What happens when I arrive for my scan?
You will change into a gown and remove metal objects that could affect the images. A nurse or radiographer will place an intravenous (IV) line. Kidney-function testing is based on risk factors, acute illness, and local policy rather than being required for every patient.
How is the procedure performed?
You will lie flat on your back on the scanner table. The table will slide slowly into the doughnut-shaped CT scanner. The scan team will leave the room but can see and hear you. During the scan, contrast dye is injected rapidly through your IV. You will feel a sudden wave of warmth and a metallic taste in your mouth. The table will move through the scanner as images are taken. You may be asked to hold your breath for 10 to 15 seconds.
How long does a CT aortogram take?
The actual scan takes only about 10 to 15 seconds. However, the preparation, IV insertion, and post-scan observation take about 30 to 45 minutes.
Is there any discomfort?
The scan itself is painless. You will feel a brief pinch from the IV needle. During the contrast injection, you will feel a warm flushing sensation throughout your body and a strong feeling that you have wet yourself (this is a normal sensation caused by the dye and passes quickly).
Are there risks?
The examination uses ionising radiation and iodinated contrast. Allergic-like reactions can occur and severe reactions are rare. People with acute kidney injury or severe chronic kidney disease require individual review; the causal kidney risk from modern intravenous contrast is lower than historically believed. Pain or swelling at the injection site must be reported immediately.
Can children have this scan?
Children may have CT angiography when it is clinically justified. The protocol and contrast dose must be adjusted for size and the clinical question, and ultrasound or MRI should be considered when equally suitable.
Can I have this scan if I am pregnant?
Pregnancy Precaution
Tell the clinician and CT team if you are pregnant or could be pregnant. Ultrasound or MRI may be preferred when they can answer the question without harmful delay, but CT angiography should not be withheld when a serious aortic emergency is suspected and it is the most appropriate timely test.
When will I get my results?
A radiologist will review the images and communicate urgent findings to the treating team. Formal report timing varies by urgency and facility; ask when and how the result will be provided.
What if the scan finds something?
If the scan detects an aneurysm or dissection, your referring doctor will discuss management immediately. A large aneurysm or dissection may require urgent surgery or a stent placement, while smaller aneurysms are monitored with regular scans.
When should I seek urgent help?
Call emergency services for sudden severe chest, back, or abdominal pain; fainting; new weakness; or a suddenly cold, pale, painful, or numb limb. Do not wait for a scheduled outpatient scan.
Questions to ask your team
- Which part of the aorta is being examined and how urgent is the suspected condition?
- What IV contrast, kidney-function, and medication instructions apply?
- Which new chest, back, abdominal, fainting, or limb symptoms require emergency care now?
Sources and further reading
- RadiologyInfo: CT angiography
- ACR Manual on Contrast Media
- FDA: Computed tomography benefits and risks
Conclusion
CT aortography can rapidly assess serious aortic disease. Follow the centre's specific fasting and medication instructions, and tell the team about pregnancy, kidney disease, acute illness, metformin, or a previous iodinated-contrast reaction.