Angiography (catheter angiogram)

Category: Imaging & Scans · All imaging & scans

What it is

An angiogram is an X-ray procedure in which contrast dye is injected through a fine tube (catheter) placed into a blood vessel, so that arteries or veins and any narrowings or blockages show up clearly.

Why it is done

It is used to investigate narrowed or blocked blood vessels — for example in the heart, legs, kidneys or brain — and sometimes to deliver treatment at the same time, such as widening a narrowed artery.

How to prepare

You will usually fast for several hours beforehand. Blood tests and kidney function are checked, and the team will ask about allergies and blood-thinning medicines. The entry site (usually the groin or wrist) is shaved if needed.

What happens during the procedure

You lie on an X-ray table and the entry site is numbed with local anaesthetic. The catheter is passed through the vessel using X-ray guidance and dye is injected while pictures are taken; the dye can cause a brief warm flush. The procedure usually takes 30 to 60 minutes, longer if treatment is done at the same time.

Afterwards — recovery & results

You will rest in bed for a few hours afterwards while the entry site is checked, and most people go home the same or the next day. You will be told to watch for bleeding or swelling at the site and to drink fluids to help clear the dye.

Risks & considerations

Risks include bruising or bleeding where the catheter entered, an allergic-type reaction to dye, effects on the kidneys, and rarely damage to the blood vessel or disturbance of heart rhythm. The team will explain the balance of risks and benefits for your situation.

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Frequently asked questions

Is an angiogram the same as an angioplasty?

An angiogram is the diagnostic picture-taking part. Angioplasty is a treatment — widening a narrowed artery, often with a stent — that can be done during the same procedure if a suitable narrowing is found.

Will it hurt?

The entry site is numbed, so you should feel pressure rather than pain. The dye injection often causes a short warm flush that passes quickly.

Related procedures — Imaging & Scans

Abdominal ultrasound Barium swallow and meal Breast ultrasound Carotid Doppler ultrasound Chest X-ray Coronary CT angiography

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Please note: This page is educational information about a medical procedure or test. It does not replace the instructions of your own care team, who know your situation and whose preparation, fasting and medication advice you should follow if it differs from anything here. If you have symptoms that worry you, or an appointment you do not understand, contact your clinical team.