Angiogram (cardiac catheterisation)

An angiogram is a test to find out more about your heart. It can show whether your heart is pumping properly. It can also show if there’s any sign of damage or disease affecting the blood vessels or heart valves.

What is an angiogram?

An angiogram gives detailed images of your heart and its blood supply. It can help to show if the blood vessels are narrowed or blocked. The coronary arteries supply blood to your heart. If they are blocked, the test can show where and how serious the blockage is. 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. The dye makes 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:

• a high fever
• an infection
• uncontrolled high blood pressure
• kidney problems
• had an allergic reaction to the dye in the past

Also, let your doctor know if you’re pregnant or breastfeeding. They will advise if an angiogram is suitable for you.

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.

The catheter can go in through either your groin or wrist. Your doctor will discuss and explain the risks and benefits of each approach. Your doctor will explain what will happen before, during and after the procedure. 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. Once you feel happy for the procedure to go ahead, you’ll be asked to sign a consent form.

Your doctor will explain how to prepare for your angiogram. Let them know if you take any medicines or have any health conditions or allergies. You may need to stop taking certain medicines but discuss this carefully with your doctor. Don’t stop taking any medicines unless your doctor tells you to.

It’s important not to eat or drink anything for several hours before your angiogram. Your doctor will explain exactly how long for.

Your doctor may suggest you give up smoking  before your angiogram. Smoking increases the risk of heart problems during and after the procedure. It also means your wound is more likely to become infected.

You 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 be awake during the procedure. Your doctor may give you a sedative to help you relax. You can usually go home the same day and don’t need to stay in hospital overnight.

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)

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 drip in your arm. Tell your nurse if you feel unwell or uncomfortable at any time.

You will 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, the local anaesthetic may cause 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. 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 the dye and take 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 it for about 20 minutes or you’ll have a small plug put in to seal it. This dissolves on its own over the next few weeks.

What to expect afterwards

If you had your angiogram through 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.

If the catheter was put in 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 your wrist or groin for bleeding, swelling and pain. You may be asked to drink plenty of fluids to help flush the dye out of your body.

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

It’s important to take it easy for the rest of the day after your procedure, to allow the access site time to heal. Don’t do any vigorous exercise or heavy lifting for about three days.

Keep the dressing over your wound (access site) for as long as your doctor advises you to. They will also give you advice about when you can shower and about keeping the dressing dry.

If you had a sedative, you may find that you’re a little unsteady on your feet 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. You may have some bruising, swelling or bleeding where the catheter entered your artery. This should disappear on its own after a few days. If it continues or gets worse, contact the hospital where you had the angiogram.

During your angiogram, you may have some mild chest pains or a fluttery heartbeat. 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 problems with vision. These symptoms are usually mild and disappear quickly, but tell your nurse or doctor straightaway if you notice them.

Complications of an angiogram

Most people don’t have any complications after an angiogram. Any that do occur tend be mild and can be easily treated. You’re more likely to have complications if you already have other health conditions, such as diabetes or kidney problems. Your doctor will discuss the pros and cons of having an angiogram with you.

Infection

You may develop an infection at the access site, although this is uncommon. Your wound may become 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. This usually gets better within a day but your doctor can give you some medicines to prevent and treat it. 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 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 also reduce the chance of kidney problems by making sure you have enough fluids in your body before your angiogram.

If you have kidney problems from diabetes and take metformin, tell your doctor. You may need to stop taking this medicine for two days after your angiogram.

Irregular heartbeat (arrhythmia)

You may develop an irregular heartbeat during your angiogram. This is quite common and usually goes away quickly on its own. If necessary, 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 or after an angiogram. This is called a haematoma. It usually goes away on its own. Contact the hospital ward where you had the procedure if it doesn’t get better. You may need to have it drained.

Heart attack or stroke

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