Having a coronary angiogram

A coronary angiogram is a procedure that lets us see inside your coronary arteries. They are vessels that supply blood to the heart muscle.

The procedure:

• gives us important information about the structure of your heart and how well it is working
• shows if there are any narrowings or blockages

Preparing for a coronary angiogram

Before having a coronary angiogram, you can generally continue to take your usual medicines. We tell you in your admission letter if you need to change the amount (dose) or stop taking any of them temporarily. You might need to stop taking or change your doses of:

• anticoagulant medicines that help to prevent blood clots (including warfarin and newer oral anticoagulants or NOACs like rivaroxaban)
• medicines that contain metformin and other medicines for diabetes (including insulin)

If you take any of these medicines but have not received instructions, please contact the cardiology clinical nurse specialist team (phone 020 7188 7188 extension 55613). You need to do this at least 2 weeks before you come to hospital for the procedure, or as soon as is otherwise possible.

You need to bring with you all the medicines that you currently take or use. This includes:

• any medicines that you get from your doctor on prescription
• medicines that you buy from a pharmacy or shop
• any complementary and alternative medicines, such as herbal remedies

   

You can have a light breakfast before 6am on the morning of your procedure but must not eat after that. You can drink water only up to the time of the procedure.

It is best to have a shower or bath on the morning of the procedure to reduce your risk of infection.

Giving your permission (consent)

We want to involve you in decisions about your care and treatment. If you decide to have a coronary angiogram, we will ask you to sign a consent form. This says that you understand what is involved and agree to have the treatment.

You can read more about our consent process.

During the procedure

We do the procedure in a cardiac catheter laboratory.

If you are not having any more treatment (such as a thin tube called a stent being inserted) at the same time, the coronary angiogram will take about 30 minutes. The procedure could take up to 2 hours, depending on your anatomy (the structure of your body). You need to lie flat on a table for at least this length of time.

What happens during the procedure

1. We give you a local anaesthetic by injection. This temporarily makes an area of your body numb while you stay awake for the procedure. 
2. We then make a small cut (incision) in your wrist or groin and insert a thin tube called a sheath.
3. We pass a long, thin, flexible tube called a catheter through the sheath and into a blood vessel.
4. Using X-ray images as a guide, we pass the tip of the catheter up to your heart and coronary arteries. 
5. We inject a substance called a contrast agent into the catheter and take X-ray images (angiograms). They show if your coronary arteries are narrowed anywhere.

Sometimes, it is not clear how severe a narrowing is from the angiogram images. In this case, we might either:

• put a wire into your coronary artery to measure the blood pressure
• use a tiny device (imaging catheter) to scan the artery from inside

During this process, we might give you medicine through a drip. This may briefly make you feel short of breath or cause some chest discomfort. When the process is finished, we remove the catheter and any wires. Your symptoms will then resolve quickly.

You are awake during the procedure. We can give you light sedation (a medicine to make you feel relaxed and sleepy) and pain medicine, if needed.

How the procedure feels

A coronary angiogram is not a painful procedure. However, it might feel a bit uncomfortable at times, and you may get some slight chest pain. 

If you do have any pain or feel unwell, please tell the team looking after you immediately.