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Conditions and treatments 

Coronary angioplasty

Coronary angioplasty

Coronary angioplasty is a procedure to unblock a coronary artery. A catheter (flexible tube) with a small balloon at the end is inserted through an artery in the groin or arm. The balloon is directed to the blockage using X-ray guidance.


Once in place, the balloon is inflated. This pushes the fatty material out of the path of the blood and improves the blood supply in the heart.


When a coronary angioplasty is performed as an emergency treatment for a heart attack, it is called a primary angioplasty.

Coronary stenting 

In most cases a stent will also be left in the artery to keep it open - sometimes called coronary stenting. The stent is a small expandable metal tube which is fitted over the balloon. When the balloon is inflated, the stent expands to hold open the narrowed artery. The balloon is then deflated and removed, leaving the stent in place.


Royal Brompton has a long record of carrying out these procedures, having performed the UK's first coronary angioplasty in 1980 and implanting the first coronary stent in 1988.

Your coronary angioplasty procedure

Watch our short films to understand more about your coronary angioplasty procedure


Benefits, risks and alternatives

Benefits of coronary angioplasty

Coronary angioplasty aims to widen narrowed blood vessels, to help increase the flow of blood to the heart. This decreases the risk of a heart attack, reduces the symptoms of angina, and slows the progress of coronary artery disease.

Alternatives to coronary angioplasty

Medication can only treat the symptoms of coronary artery disease and, unlike angioplasty, will not affect the progression of the disease. Coronary artery bypass grafting (CABG – more commonly known as "heart bypass") can be used to "get around" the narrowed sections of arteries.

For some people angioplasty will offer the best treatment and for others grafting will be more appropriate. Your doctor will advise you on which he thinks is best for you and can explain his opinion.

Risks of coronary angioplasty

There are risks involved with coronary angioplasty – as there are with any medical procedure. When we advise a patient to have an angioplasty it is because we believe the benefits outweigh the risks in their case.

Exact risks vary from patient to patient but the most common complications associated with coronary angioplasty are:

  • Bruising and swelling where the catheter was inserted - It is usual to have bruising and swelling in the groin or wrist for a few days following coronary angioplasty. Occasionally the swelling will increase and/or the wound will become infected. If this happens, we can typically treat the infection with a course of antibiotics.

  • Allergic reaction to the dye used during the coronary angioplasty – We use a dye to help us see the coronary arteries on X-ray. Some people have an allergic reaction to this dye – also known as "contrast". If you have previously had an allergic reaction to X-ray contrast, please let us know. Reactions are rare, and can be treated.

  • Artery becomes completely blocked during the procedure – Rarely coronary angioplasty can cause the artery to become completely blocked. Should this happen, an emergency coronary artery bypass operation would be performed.

  • Heart attack during the coronary angioplasty - Occasionally patients have a heart attack while undergoing angioplasty. This is a rare complication.

  • The catheter damages an artery - Rarely, the catheter damages a coronary artery. In these instances, we may need to perform emergency heart surgery in order to repair the damage.

  • Risk of radiation from X-ray – Radiation is used as sparingly as possible and we believe the benefits far outweigh the risks to your health. If you have any concerns about X-rays or radiation, please just discuss them with us. Radiation affects growing cells, and so can be harmful to unborn babies. Female patients who are pregnant or think they may be pregnant, should tell us before their scan.

What will happen if I do not have the procedure?

If you suffer from coronary artery disease and have been advised to have an angioplasty and you do not, your coronary artery disease is likely to advance further and your risk of heart attack will increase. 

At this point, it is possible that more invasive treatment than coronary angioplasty – such as emergency heart surgery, or coronary artery bypass graft – will become necessary.

Royal Brompton

Sydney Street,
London SW3 6NP
Tel: +44 (0)20 7352 8121


"I had an angiogram leading to an angioplasty (stent) this week. This is the only hospital where my blood pressure goes down rather than rises. I know why. The manner of all staff from reception onwards is like no other hospital I have visited. 

"Friendly, helpful, joyful. They all put you completely at ease, I am a nervous person by nature but this place makes you relaxed. My consultant was as expected extremely polite and took time to explain the whole procedure. I cannot speak highly enough of everyone in Harefield."

- Review on NHS Choices, February 2017