Catheter ablation

Ablation illustration

If you feel your heart beating abnormally, you may need a catheter ablation. Dr Guy Haywood, Consultant Cardiologist in Plymouth, explains.

What is a catheter ablation and why might I need one?

Catheter ablation is a drug-free solution for a wide range of abnormal heart rhythms (arrhythmias). An ablation is usually performed when the arrhythmia is causing symptoms that interfere with the person’s quality of life, such as stopping them from doing their job or normal daily activities, and when they haven’t responded to other treatments, such as medicines.

A catheter ablation involves passing thin, flexible tubes, called catheters, through the blood vessels to the heart. The catheters record the heart’s electrical activity and can pinpoint where the arrhythmia is coming from.

For around 90 per cent of those who have it, catheter ablation is successful

The area of heart muscle at the affected site is then destroyed using either heat (radiofrequency ablation) or by freezing (cryoablation). This creates scar tissue, which doesn’t conduct electricity and so knocks out a trouble spot or acts as a fence around the problem area to prevent the electrical signals from reaching the rest of the heart and causing the arrhythmia.

How does my doctor know what type of arrhythmia I have?

For many people, their arrhythmia is paroxysmal, which simply means it comes and goes. This often makes capturing it on an ECG recording very difficult.

You will probably need to have a series of tests to show how your heart functions and determine what type of arrhythmia you have, so the doctor can decide the best treatment for you. These tests can include a chest X-ray, ambulatory ECG monitor (or Holter monitor), an echocardiogram, CT angiogram and MRI.

Sometimes, an event recorder that the patient can keep with them and activate when they feel they are in the arrhythmia is helpful. These are starting to appear as mobile phone attachments.

In the most difficult cases, where the arrhythmia causes bad symptoms but occurs only once or twice a year, a device like a computer memory stick can be implanted under the skin to record any arrhythmias automatically. This is called an implantable loop recorder.

Ablation explained

Catheters (small tubes) enter your heart via a vein or artery in your groin or neck. The arrhythmia trigger site is identified and radiofrequency energy is then used to inactivate or cordon off the affected area.

What happens once I agree to have a catheter ablation?

Your doctor will check if you need any preparation before your procedure. For example, you may need certain blood tests, and some patients must take an anticoagulant medicine (such as warfarin) for a few weeks before and after their ablation.

How long does the procedure take?

The shortest ablation can take as little as 15 minutes, whereas a more difficult and complex procedure can take three or four hours. However, this usually includes preparation before and a recovery period afterwards.

We closely monitor each patient for 15 to 30 minutes after the procedure to make sure it has been a success. Once on the ward, each patient continues to be observed for a few hours before they are allowed home, although some people may need to stay in hospital overnight.

Will I need a general anaesthetic?

For simpler, shorter ablation procedures, a general anaesthetic is unnecessary

For simpler, shorter ablation procedures, a general anaesthetic is unnecessary. A mild sedative is usually enough to keep you relaxed.

However, for prolonged procedures or ones where other treatments are needed – for example, when the heart needs controlled electrical shocks – a general anaesthetic will be given. You are also likely to be given painkillers.

How risky is it?

Complications are extremely infrequent and for around 90 per cent of those who have it, catheter ablation is successful. However, some patients may experience pain or bleeding at the sites where the catheters have been inserted or an allergic reaction to medications, although this is rare.

Theoretically, high doses of radiation from the X-rays can burn the skin, but this is extremely rare and usually only affects people who are very overweight or obese.

The risk of a disabling stroke is around one in 500, and the chance of a bleed around the heart needing to be drained is about one in 200.

The risk of death is around one in 1,000. Because of these risks, some patients refuse to undergo catheter ablation. A stroke, for example, can cause lifelong disability; that’s a frightening thought. Having these risks and alternative treatment options explained by your cardiologist in the right context and in the correct manner and tone, can make all the difference and offer reassurance.

How long is the recovery period after a catheter ablation?

Brisk walking by the second week is the norm

Once you are able to go home, you’re usually advised to rest for the remainder of the week and the weekend. This may mean taking a couple of days off work, particularly if you do a physical or demanding job.

You may also need to gradually increase the amount of exercise you do, especially if you hadn’t been doing much prior to the ablation procedure. Brisk walking by the second week is the norm.

Will I know straight away whether it has worked?

Immediately afterwards you might still have ongoing symptoms, usually palpitations, but these will settle and around 8-10 weeks later it will be much clearer as to whether the ablation has worked. Some people might experience short-term chest pain because of some inflammation of the heart but this usually settles on its own after 7-10 days.

If the ablation is a success your doctor will discuss stopping some of your medications. You’ll be followed up for 12 months afterwards and if your symptoms are still controlled the treatment has been successful and you can be discharged.

For some people, however, their AF may return, in which case it is possible to try again. 

What are the alternatives?

Treatment will depend on the type of arrhythmia you have. Sometimes, simply finding out what you are feeling and why is enough. For example, lots of us get extra heartbeats (ectopics) from time to time and, although these can be a nuisance, they are usually harmless and require no treatment. Knowing they are not dangerous and trying not to focus on them can help you feel better.

There are also a number of medicines that can help to keep your symptoms under control.

Dr Guy HaywoodDr Guy Haywood

Dr Guy Haywood is a specialist in adult cardiology, focusing on heart rhythm problems and coronary artery disease. Based in Devon, he helped set up the South West Cardiothoracic Centre.

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