What is a renal angiogram? 

Also known as renal angiography, a renal angiogram uses X-ray to produce detailed images of the kidney (renal) arteries. As blood vessels don’t show up clearly on a standard X-ray, a special contrast dye is injected to highlight them.

A renal angiogram can show whether there are any narrowed areas in a blood vessel causing a partial or complete blockage.

What does a renal angiogram involve?

It’s usually a day procedure carried out in hospital.

A thin plastic tube called a catheter is inserted into your artery using a needle. This is usually through an artery in your groin and guided under X-ray towards the arteries that supply the kidneys.

Contrast dye is injected into the artery through the catheter, and X-rays are taken as the dye flows through your blood vessels to the kidneys.

If a narrowing causing a partial or complete blockage is seen in one or both renal arteries, you may have go on to have a procedure to open the area, either at the same time or a later date. This could include a renal angioplasty and stenting or an embolisation, when the blood supply to one of your kidneys is stopped on purpose using small metal coils.

Who is it for?

Your kidney doctor may recommend an angiogram if they think you might have renovascular disease (RVD) or atherosclerosis, the narrowing or blockage of one or both kidney arteries due to a build-up of fatty deposits, which can cause raised blood pressure and reduced kidney function.

An angiogram can confirm narrowing or blockage and help you and your doctor decide on next steps.

Is a renal angiogram safe? Are there any alternatives?

The procedure is generally safe. It’s common to have temporary bruising, soreness and a small bump close to where the catheter was inserted.

There’s a small risk of minor complications, such as:

• an infection where the cut was made, which can be treated with antibiotics
• a mild reaction to the X-ray dye, such as an itchy rash, which can be managed with medicine
• bruising around the site where the needle is inserted into the artery
• failure to do the procedure – as with any procedure, there is always a risk that attempts might fail

More serious complications are very rare but may include:

• a serious allergic reaction to the dye (anaphylaxis)
• kidney damage caused by the dye, although it’s usually temporary
• damage to a blood vessel, which may need to be repaired with further surgery. This damage could cause a reduction in kidney function
• some bits of fatty material or blood clot can move during the procedure and travel further along the bloodstream. This is called an embolism. If it lodges in a small kidney blood vessel, it can reduce blood flow to a small area of the kidney.

Your healthcare team can talk through the potential risks and answer any questions you have.

Where will the renal angiogram take place?

In hospital, in the X-ray or radiology department.

Who will perform the renal angiogram?

An interventional radiologist, a specialist in catheter-based imaging, will perform the angiogram, supported by other staff.

What happens before the procedure? How do I prepare?

• The hospital team will ask about your medical history, including any allergies, medications and previous scans.
• They’ll tell you if you need to stop any medications.
• Guidelines on eating and drinking before the test can vary between hospitals, so follow the directions you’re given.
• If you have reduced kidney function, you may receive intravenous (IV) fluids before and after the angiogram.

What happens during the procedure? 

The procedure takes between 30 minutes and 2 hours, and you’ll be awake throughout. You may be given sedative medication to help you relax.

You lie on an X-ray table. After cleaning the skin and numbing the area with local anaesthetic, the radiologist uses a needle to insert a catheter into an artery, usually through your groin, and guides it to the renal arteries using X-ray.

Contrast dye is injected so the arteries show clearly on the screen, and images are recorded for your kidney team. When the dye is given, you may feel a brief warm flush or the feeling that you have passed urine.

The radiologist may carry out treatment to open a narrowed artery, such as inserting a balloon (angioplasty).

The catheter is then removed and pressure is applied to the entry site.

What happens immediately after a renal angiogram?

You’ll go to the recovery ward for observation. Nurses will check your pulse and blood pressure regularly. They will also look where the catheter was inserted to make sure it is okay. You will need to lie flat for a few hours to prevent bleeding from the incision site.

You may go home that day or stay overnight, depending on the time you had the procedure.

What should I expect when I get home?

• Rest for the remainder of the day – ideally, you should have someone with you for the first 24 hours.
• You can eat and drink normally.
• A small bruise or tenderness at the puncture site is common and settles within a few days.
• Follow the activity advice you’re given by your hospital team. Avoid anything strenuous until the site has healed.
• Contact your hospital team if you notice increasing pain, a rapidly enlarging bruise, bleeding that doesn’t stop, fever, chest pain, or shortness of breath, or have concerns about the amount of urine you’re passing.

How will I get the results?

Usually, the images need to be studied and won’t be available for a few weeks. The radiologist will send a report to your referring team, who will discuss them with you.

Is there anything else I need to know?

You won’t be able to drive immediately afterwards, so you'll need to arrange transport home.

Publication date: 01/2026

Review date: 01/2029