What is coronary angiography?

Coronary angiography is an x-ray procedure or test to examine the arteries of your heart. Angiography provides information on the extent and location of any narrowing in the coronary arteries. The x-ray images are called coronary angiograms, while other terms used are cardiac catherisation and coronary arteriography. Sometimes other tests are done at the same time, eg, to measure the blood pressure within the heart chambers, and to check the functioning of the heart valves and of the heart pump.

What are the coronary arteries?

The coronary arteries supply your heart muscle with vital blood and oxygen so that your heart can pump blood around the body. The results of the angiography, which will give information on any narrowing in the coronary arteries, will help your doctor decide what treatments, if any, are best for you.

How will I be prepared for the angiography?

You will usually be seen at a pre-admission clinic some days or weeks beforehand. At the clinic, or when you arrive for angiography, you will likely be asked to have blood tests, an electrocardiogram (ECG), and a chest x-ray.

Your doctor/cardiologist will decide what food and drink you may have the night before and on the day of the test. If you have been taking medication, he or she will decide whether you should continue this before your test. If in doubt ask your doctor/cardiologist. You should bring all your medications with you into hospital.

Will I be admitted to hospital for coronary angiography?

You will usually be admitted to hospital on the day you are scheduled to have your angiography. The doctor or nurse will explain the procedure and any risks, and will answer any questions. They will ask you about your medical history and note your allergies and medications. You may be given a sedative tablet to help you relax, but will still be able to follow the doctor's instructions.

Where is the procedure carried out?

Coronary angiography is done in a cardiac catheterisation laboratory (cath lab). You will be taken there from the ward on a movable bed.

Once you are in the laboratory you will be moved onto an examination table. You will be lying directly under an x-ray camera through which the angiography procedure can be viewed. The procedure takes about 30 minutes.

What does the procedure involve?

The catheter insertion site in your arm or groin will be cleaned and covered in sterile sheets. The doctor will inject local anaesthetic into this area. When this area is numb, an introducing sheath (narrow tube) is inserted into your artery. A thin, flexible plastic tube called a catheter is then threaded through the sheath.

The catheter is guided through the artery until it reaches the part of the aorta, immediately outside the heart, where the coronary arteries begin. This should not cause any discomfort. The catheter's movement is monitored by x-rays which your doctor can see on a television screen. You may be able to watch this too. Ask your doctor if you would like to.

The coronary arteries do not show up on normal x-rays, so a special contrast fluid (dye) is used. Once the catheter is in place, the contrast fluid is injected through the catheter to highlight the blood in the coronary arteries. This will show any narrowings.

You may be asked to hold your breath while x-rays are continuously taken of your heart and coronary arteries. Your cardiologist will watch and monitor the procedure on a television screen.

Will there be discomfort with angiography?

You should tell the doctor or nurse if you start to feel flushed or develop chest pain. Common feelings, which are normal, include:

• slight pressure as the catheter is inserted, but not when it is inside your blood vessels
• occasional missed heartbeat - but your heart rate will be monitored throughout the procedure
• wanting to pass urine and feeling flushed as the contrast fluid is given.

Very rarely, an allergic reaction to the x-ray contrast fluid can happen, so it is important to know if you have had a previous reaction. If you develop itching, a rash or welts, medications are given to stop the reaction immediately.

What happens after the procedure?

The sheath in your groin or arm will be taken out at the end of the procedure. Pressure will be applied to the area for up to 20 minutes to stop any bleeding, or a tiny plug inserted into the artery to seal the insertion site. It is very important that you lie still during this time to prevent bleeding. If the catheter was inserted in your groin, you will need to lie flat for several hours. If the catheter was inserted into your arm, you will be able to sit up and walk soon after, with help from your nurse.

When you return to the ward the nursing staff will regularly check the catheter insertion site, your blood pressure, pulse and circulation of either your lower leg or arm, depending on where the insertion site was.

It is most important to follow the nurse's instructions. He/she will let you know when it is safe to sit up and slowly move around.

• If you feel any bleeding, pain, dizziness, sweating or a warm, wet feeling around the catheter insertion site, call the nurse immediately.
• If you experience discomfort at the site, inform the nurse and you will be given pain relief.
• It is normal to have some bruising around the site and for it to be slightly tender.
• You may feel a small lump where the sheath was inserted. This should disappear over the next few weeks.

Before going home, a nurse will teach you how to check the site for swelling or bleeding and will explain what to do if this does happen. You will be advised not to do any heavy lifting or straining for about a week to prevent bleeding or bruising from the insertion site.

What about my results?

If the angiogram shows a narrowing that can be treated immediately, your cardiologist may decide to continue to perform an angioplasty (procedure to open a narrow artery). In most cases this will include inserting one or more stents.

Alternatively, an angioplasty and stenting might be scheduled for a later date, or coronary artery bypass graft surgery may be recommended. Your cardiologist will also prescribe appropriate medications for you to take.

A letter will be sent to your GP, giving the results of your angiography. You should ask a friend or relative to drive you home and you should not be alone on the night following your procedure.

Original material provided by the Heart Foundation of New Zealand, July 2009. Reviewed by everybody, January 2011.