Angiogram (cardiac catheterisation)

Expert reviewer, Dr Tim Cripps, Consultant Cardiologist
Next review due September 2020

An angiogram is a test to find out more about your heart. It can show whether your heart is pumping properly.

An angiogram can also show if there’s any evidence of damage or disease affecting the blood vessels.

What is an angiogram?

An angiogram gives detailed images of your blood vessels and heart. It can help to show if blood vessels called coronary arteries, which supply blood to your heart, are narrowed or blocked. If they are, the test can show where and how seriously they’re affected. The doctor may be able to treat problems that show up during an angiogram. An angiogram can also show:

  • how well your heart is pumping blood
  • any damage after a heart attack

During an angiogram, your doctor will put a long, thin, flexible tube called a catheter into an artery in your groin or wrist. This procedure is called cardiac catheterisation. The doctor will guide the catheter to your heart and inject a dye through it. This will mean your heart and coronary arteries show up more clearly on X-rays.

Most people can have an angiogram. But the test may not be suitable if you have:

You may not be able to have an angiogram if you’ve had an allergic reaction to the dye before. You should also let your doctor know if you’re pregnant or breastfeeding, as there can be some risks to doing an angiogram in these situations.

Preparing for an angiogram

You’ll meet the doctor carrying out your angiogram to discuss your care. It may be different from what’s described here, because it’ll be designed to meet your individual needs.

Your doctor will explain how to prepare for your angiogram. Let them know if you take any medicines and have any health conditions. You may need to stop taking anticoagulants, such as warfarin, for up to three days before your test. This is because anticoagulants thin your blood, which means you’re more likely to bleed if you have surgery. But don’t stop taking any medicines unless your doctor tells you to.

It’s important that you don't eat or drink anything for several hours before your angiogram. Your doctor will explain exactly how long you need to do this for.

Your doctor may suggest you give up smoking before your angiogram. Smoking increases your chance of developing heart problems during and after surgery. It also means your wound is more likely to become infected. If you wish to stop smoking, speak to your pharmacist, local NHS Stop Smoking Service or GP.

You’ll usually have an angiogram under local anaesthesia. This completely blocks pain from where the catheter enters your artery (in your groin or wrist) and you’ll stay awake during the procedure. Your doctor may give you a sedative too, which will help you to relax. You can have an angiogram and go home on the same day. You don’t usually need to stay in hospital overnight.

Your surgeon will discuss with you what will happen before, during and after your surgery. If you’re unsure about anything, don’t be afraid to ask. No question is too small. It’s important that you feel fully informed, so you feel happy to give your consent for the operation to go ahead. You may be asked to do this by signing a consent form.

What happens during an angiogram?

An angiogram usually takes about half an hour. Your angiogram may be done by either:

  • a radiologist (a doctor who specialises in understanding X-rays)
  • a cardiologist (a doctor who specialises in heart conditions)

A radiographer, who is trained to take X-rays, will also be part of the team that looks after you.

You’ll have your angiogram in a room called a catheter lab. Your nurse will ask you to change into a hospital gown. A heart monitor will record your heart rate and rhythm during the procedure. You may be given extra fluid through a vein in your arm. Tell your nurse if you feel unwell or uncomfortable at any time.

You’ll be asked to lie on a table with an X-ray machine above your chest. Your doctor will inject local anaesthetic into your skin where the catheter will enter your artery – this is called the access site. If this is through your groin, you may notice pins and needles and tingling in your leg on that side.

Your doctor will make a small cut in your skin, before threading the catheter into the artery in your groin or your wrist. They will then move it up through your artery to the opening of your coronary arteries. Your doctor will use X-rays of your heart (shown on a screen) to carefully guide the catheter into your heart. When the catheter has reached the right place, your doctor will inject a dye into the catheter. You’ll have more X-rays as the dye flows through your arteries and heart. These will show up any narrowing or blockages.

You won’t feel the catheter in your artery, but you may notice a warm flush throughout your body when the dye is injected.

Your doctor will remove the catheter when the angiogram is finished. The access site then needs to be sealed. Either your nurse will press on the access site for about 20 minutes or you’ll have a small plug inserted to seal your artery.

If you had the catheter inserted into your wrist, you’ll be given a tight band to wear around your wrist. You’ll need to keep this on for two to three hours after your angiogram.

What to expect afterwards

If your angiogram was done through your groin, you’ll need to lie flat for a few hours so your artery can seal properly. You’ll need to keep your leg (or arm if your wrist was used) as straight as possible to reduce bleeding. Your nurse will regularly check your blood pressure and heart rate. They’ll also check the access site (where the catheter entered your artery) for bleeding, swelling and pain. You may be asked to drink plenty of fluids to help the dye flush out of your body when you go to the loo.

You’ll usually be able to go home when you feel ready but make sure someone can take you. You shouldn’t drive straight after an angiogram.

If your procedure was urgent, the healthcare team who carried out your angiogram may talk through your results with you before you go home. If it wasn’t urgent, your doctor will contact you to discuss your results. If you have any problems with the access site after you get home from the angiogram, it’s important to contact the hospital ward where you had the procedure. You should be given a contact number before you go home.

Recovering from an angiogram

Everyone recovers from an angiogram differently. Take it easy for the rest of the day after your procedure. And don’t do any vigorous exercise or heavy lifting for about three days.

Keep the dressing over your wound (access site) for 24 hours. You can then have a shower and carefully remove it. If the access site gets wet, dry it by patting it with a towel.

A sedative can affect you in many ways. You may find you’re not so coordinated or that it’s difficult to think clearly. This should pass within 24 hours. In the meantime, don’t drive, drink alcohol, operate machinery or sign anything important. Always follow your surgeon’s advice.

If you need to fly – for work or a holiday – you should be able to do so the next day. But be sure to check this with your doctor before having the test.

Side-effects of an angiogram

Generally, having an angiogram in your wrist will cause fewer side-effects than having the test through your groin. An angiogram through your wrist should also be a more comfortable procedure.

During your angiogram, you may have some mild chest pains or a fluttery heartbeat. If you have the catheter through your groin, you may notice pins and needles and tingling in your leg on that side. The dye may cause a warm flushing sensation in your body. It may make you cough or feel sick. You may also have a rash or blurred vision. These symptoms are mild and disappear quickly, but tell your nurse or doctor as soon as you notice them.

You may have some bruising, swelling or bleeding where the catheter entered your artery. This should disappear after a few days on its own. If it continues, contact your doctor or nurse.

Complications of an angiogram

Most people don’t have any complications after an angiogram. Any complications that do occur tend be mild and can be easily treated.


You may develop an infection at the access site, though this is rare. Your wound may be red and swollen and leak pus within a few days after your angiogram. If you notice this after you get home, contact the hospital ward where you had the procedure straightaway. You should have been given their number when you left the hospital. You may need a course of antibiotics.

Allergic reactions to the dye

Some people have an allergic reaction to the dye used in an angiogram. This usually gets better within a day but your doctor can give you some medicines to prevent and treat this. It’s important to tell your doctor if you have any type of allergy. If you have any allergies or asthma, you may be more likely to be allergic to the dye.

Kidney problems

Sometimes the dye used in an angiogram can cause kidney problems, especially if your kidneys already don’t work very well. Before your angiogram, tell your doctor if you have any kidney problems so they can use a different dye. Your doctor can reduce the chance of kidney problems by making sure you have enough fluids in your body before your angiogram.

You’re also more likely to have kidney problems afterwards if you have diabetes or high blood pressure. Tell your doctor if you take metformin, a common treatment for diabetes. You may need to stop taking this medicine for two days after your angiogram.

Irregular heartbeat (arrhythmia)

You may develop an irregular heartbeat from having a catheter within your heart or because of the dye injection. If this happens during your angiogram, your doctor will treat it straightaway.

Build-up of blood under your skin (haematoma)

Blood can build up if it leaks out of the blood vessel during an angiogram. This is called a haematoma. You may need to have the haematoma drained. Contact the hospital ward where you had the procedure if you notice any problems after getting home.

Heart attack or stroke

Very rarely, the tip of the catheter can dislodge a blood clot or fatty plaque from the wall of your blood vessel. There’s a risk that these may block the blood supply to your heart or brain and trigger a heart attack or stroke.

You’re more likely to have complications if you already have other health conditions, such as allergies or problems with your kidneys. Your doctor will discuss the pros and cons of having an angiogram with you.

Frequently asked questions

  • Children can have an angiogram. Most angiograms in children aim to treat a heart problem, as well as diagnose it.

    The angiogram is the same as for adults, but it’s usually done under a general anaesthetic. This is because children may find it difficult to stay still during the test. If your child has a general anaesthetic, this means they’ll be asleep during the angiogram. The staff at the hospital will take every step to care for your child during the procedure.

    The staff will be trained specifically to do angiograms in children. They will adjust the radiation doses to your child’s size. This is because children are more sensitive to radiation. The staff will make sure the type of dye used and the catheters to deliver the dye are suitable for your child. Your doctor will also use other operating equipment that’s designed for children. Your child will recover from the angiogram in a separate area, away from adults.

    If you’re worried about your child having an angiogram, talk to their doctor. You can discuss the pros and cons of the test and see if there’s an alternative.

  • Angiograms aren’t usually painful. You usually have the procedure under a local anaesthetic. This means you don’t feel any pain where the catheter enters your artery. If you’re anxious or worried, you can have a sedative before the test. This will relieve anxiety and help you relax.

    During the angiogram, you may notice a pushing and pulling sensation around your groin. If you have the test through your groin, you may notice pins and needles and tingling in your leg on that side. If you notice any pain, tell the doctor or nurse, as they may give you some painkillers. When the dye is injected, you may notice a warm flushing sensation.

    You may have some soreness and bruising after the angiogram. This doesn’t usually need any treatment and disappears on its own. But if it doesn’t disappear or gets worse, contact the hospital ward where you had the procedure. If your wound becomes red, sore and swollen and leaks pus within a few days after your angiogram, your may have an infection. Contact the hospital ward where you had the procedure. The healthcare team there can review you and prescribe antibiotics if necessary.

    Sometimes, blood may collect under your skin where the catheter entered your artery. This is called a haematoma and can be painful. A hard lump (with or without pain) may be a sign of a false aneurysm and needs to be checked – contact the hospital ward where you had the procedure to have this checked.

  • Your doctor may ask you to stop taking warfarin a few days before your angiogram. This will reduce your risk of bleeding during, and immediately after the procedure. But don’t stop taking any medicines unless your doctor tells you to do so.

    Warfarin is an anticoagulant medicine, which can stop your blood clotting. You may take warfarin if you have a medical condition, such as atrial fibrillation, that makes you prone to blood clots. Taking warfarin can mean your blood doesn’t clot easily when you bleed. This may mean you’re more prone to excessive bleeding (haemorrhage) during or after surgery.

    Your doctor will give you information about how to prepare for your angiogram. If you take any medicines regularly, show them to your doctor so they know exactly what you’re taking.

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  • Reviewed by Graham Pembrey, Lead Health Editor, Bupa Health Content Team, September 2017
    Expert reviewer, Dr Tim Cripps, Consultant Cardiologist
    Next review due September 2020

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