What is atrial fibrillation?

Atrial fibrillation (AF) is a type of irregular heartbeat. In AF, your heartbeat is irregular and may be abnomally fast. The heart might not empty itself of blood at each beat, and a clot can form in the blood left behind. 

Why does AF increase your risk of stroke?

If blood clots form in your heart, there is a risk that it will travel in your bloodstream towards your brain. If a clot blocks one of the arteries leading to your brain, it could cause a stroke or TIA.

If you have atrial fibrillation, you are five times more likely to have a stroke. And atrial fibrillation contributes to just under 20% of all strokes in the UK. 

How do I know if I have AF?

Some common symptoms of AF include:

  • Palpitations (being aware of your heart beating fast)
  • Breathlessness
  • Chest pain
  • Fatigue.

However, some people do not have any symptoms and AF is often only diagnosed during a general medical check up.

There are four types of AF:

  • Paroxysmal AF comes and goes – it’s not there all the time. Your heart goes back to its normal rhythm without any treatment, usually within 48 hours
  • Persistent AF is where you have AF episodes that last more than seven days and it's unlikely that they'll stop on their own. You'll need treatment to restore your normal heart rhythm
  • Permanent AF is there all the time. You might be diagnosed with permanent AF if you’ve had it for more than one year and treatment hasn’t helped
  • Long-standing persistent AF is when you have had continuous atrial fibrillation for a year or longer.

As well as these four types, a small number of people may be diagnosed with "lone" AF. This is when doctors cannot find what is causing your AF, or you don’t have any risk factors for it. 

What should I do if my pulse feels irregular?

Atrial fibrillation makes your risk of stroke five times higher. If you suspect your pulse is irregular, make an appointment with your GP who will test your pulse. They may refer you for further tests to confirm whether you have AF and which type.

These tests may include the following:

  • An electrocardiogram (ECG) tests the electrical activity of your heart. It’s painless and usually takes less than 10 minutes. It may be done by your GP or in hospital
  • An echocardiogram uses sound waves to check your heart’s structure and how it’s working
  • Blood tests check for conditions that can cause AF, such as an overactive thyroid gland, anaemia, or any problems with your kidney function
  • A chest X-ray will check whether a lung problem could have caused your AF. 

AF that comes and goes can be hard to detect. To help diagnose it, you may be asked to wear a portable ECG monitor for 24 hours or more to check how your heart works over a longer period of time.

You may be referred to a heart specialist called a cardiologist. They can help you decide which types of medication are right for you and monitor them. They can also perform some procedures to treat AF, including cardioversion, a treatment that uses medication or a brief electrical shock (sometimes both) to help your heart return to its normal rhythm.

You may also be referred to an electrophysiologist who offers another type of treatment called catheter ablation. Many hospitals now have arrhythmia nurse specialists who can offer you and your family information about your treatment.

What can I do about AF?

AF is a manageable condition. The main treatment to reduce your stroke risk is blood thinning medication (anticoagulants). It's important that you discuss all options with your hospital doctor or GP, to make sure you receive the best treatment possible to reduce your risk of stroke.

Recognising and receiving proper treatment for AF is important as strokes due to AF are often more severe but are avoidable.

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