Coronary angiogram

Doctors looking away

An angiogram allows your doctor to look inside your coronary arteries and find out where and how severe any narrowed areas are.

It's also known as a coronary angiogram or a cardiac catheterisation.

The procedure helps your doctor decide what treatment you might need. It can also give information about how effectively your heart is pumping and about the blood pressure inside your heart.

An angiogram can also be helpful for investigating other conditions, such as congenital heart disease.

What happens during an angiogram?


The test is done in a cath lab. You can expect the test to last half an hour, although it can sometimes take longer.

  • Your hospital will ask you not to eat or drink anything for a few hours before your angiogram.
  • You’ll be given a local anaesthetic in the arm or groin, where a catheter (a thin, flexible tube) will be passed into the artery.
  • Using an x-ray, the catheter will be directed through your blood vessels and into your heart.
  • A special dye will then be passed through the catheter and a series of x-rays will be taken. You might feel a hot, flushing sensation from the dye. The dye will show up any narrowed areas or blockages in the artery on the x-ray.
  • During your procedure, you’ll be monitored by a heart monitor that records your heart rate and rhythm, but if you feel unwell or uncomfortable at any time, you should tell a member of the hospital staff.

What happens afterwards?

After the procedure, the catheter will be removed and you might have a small amount of bleeding. If so, the nurse or doctor will press on the cut for a little while or insert a plug called an angioseal.

They might ask you to stay in bed for a short time. Most people are able to go home on the same day, but some people may stay in hospital longer.

The most common after-effect is bruising around the groin area, if that is where your catheter was put in, and you may feel tender for a few days.

You might feel tired, but you should be back to normal within a few days. If you are worried about any of the after-effects, contact your doctor.

Many people who have a coronary angiogram go on to have a treatment called coronary angioplasty.

What is a CT coronary angiogram?

CT stands for ‘computerised tomography’. A CT scan is a sophisticated type of X-ray.

A CT coronary angiogram shows the blood flow through the coronary arteries. This test is similar to a traditional coronary angiogram. However, in this test the dye is injected into a small vein in your arm rather than an artery in your groin. This makes the test less invasive than a traditional angiogram. You will then lie on a bed which passes through a doughnut-shaped opening in a CT scanner to create an image of your heart.


A CT coronary angiogram is generally not as able to detect narrowings in small coronary arteries or in small branches as a traditional coronary angiogram. So, for now, the standard coronary angiogram is still the ‘gold standard’ for diagnosing coronary heart disease.

What are the risks?

An angiogram is a relatively safe test and serious complications are rare.

If there is bleeding from the area that the catheter was placed in, you might develop a collection of blood under the skin, which is called a haematoma. It can be uncomfortable and cause bruising, but this should go down after a few days. However, contact your doctor if you have any concerns.

The risk depends on your overall health and your individual heart condition – your doctor will not recommend the test if they don’t feel the benefits outweigh the small risk.

A small amount of radiation is used during an angiogram. If you’re exposed to lots of radiation, it can increase the risk of cancer. However, the amount of radiation is quite small. If it’s likely that you have coronary heart disease, the risks involved in not having the test may well be far greater than the risks from radiation.

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