Coronary CT angiography

Category: Imaging & Scans · All imaging & scans

What it is

Coronary CT angiography is a CT scan that uses contrast dye to picture the coronary arteries — the vessels that supply the heart muscle — and look for narrowing caused by fatty deposits.

Why it is done

It is often used for people with chest pain whose risk is thought to be low or intermediate, as a non-invasive way to check whether narrowed heart arteries are a likely cause.

How to prepare

You may be asked to avoid caffeine on the day and not to eat for a few hours. Tell the team about allergies, kidney problems, asthma and any heart-rhythm medicines you take. A blood test for kidney function is usually checked first.

What happens during the procedure

Sticky ECG dots are placed on your chest so the scanner can time pictures to your heartbeat. You may be given a medicine to slow the heart rate and a spray under the tongue to widen the arteries, then contrast dye is injected as the table moves through the scanner. It usually takes 15 to 30 minutes.

Afterwards — recovery & results

You will usually be observed briefly afterwards and can then go home. Results are reviewed by specialists and sent to your doctor, who will discuss what they mean and whether any treatment or further test is advised.

Risks & considerations

Risks include an allergic-type reaction to contrast dye, effects on the kidneys in people with kidney problems, and the radiation dose of the scan. The medicines used to slow the heart can briefly cause breathlessness or flushing.

Frequently asked questions

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