Atrial fibrillation

Heart rhythm disorder

A common rhythm abnormality, increasing with age, that raises the risk of stroke

What is atrial fibrillation?

Atrial fibrillation (also known as AF or Afib) is a heart condition that causes an irregular, often very fast heart rhythm. If you have atrial fibrillation, your heart may beat up to 100 - 175 beats per minute (BPM), compared to a normal heart rate of between 60 and 100 BPM. 

Atrial fibrillation is the most common form of cardiac arrhythmia (abnormal heart rhythm). It occurs when the atria (the heart’s two upper chambers) produce out-of-control electrical signals. These are then sent to the heart’s lower chambers (the ventricles), causing them to also beat rapidly. 

Atrial fibrillation is more common in older people, because it is often related to other pre-existing heart-related problems such as high blood pressure and coronary artery disease

At HCA UK, we provide comprehensive care for all types of arrhythmia, including atrial fibrillation. Our treatments include testing and monitoring, medication, interventional procedures like ablation therapy (which involves using high-energy radiation beams to destroy the tissue in your heart which is responsible for its irregular rhythm) and aftercare.


Symptoms of atrial fibrillation

There are a range of symptoms associated with atrial fibrillation, many of which are consistent with those of other heart conditions. However, the main symptoms of atrial fibrillation is a fast and irregular heartbeat.

You can test your heartbeat by taking your pulse in your neck or wrist. To check your pulse, sit down for at least five minutes. Press the index and middle finger of your right hand on your left wrist (or where you feel a pulse in your neck), and count the number of beats in a 30-second period. Double this number to find out your BPM. A normal resting heart rate is between 60 and 100 BPM. If you have atrial fibrillation,  more often than not your heart will be beating at over 100 BPM. 

Other symptoms of atrial fibrillation may include:

  • Palpitations: this describes the feeling that your heart is beating irregularly, very quickly (racing), pounding or fluttering. This feeling may last for several minutes at a time
  • Tiredness / fatigue
  • Chest pain which may feel like pressure or discomfort in the centre of your chest. This is known as angina, which is caused by decreased blood flow to the heart
  • Breathlessness
  • Dizziness
  • Blackouts or fainting (syncope)
  • Anxiety
  • Sweating

If you have atrial fibrillation, your heart is not working (pumping oxygenated blood around your body) as efficiently as it should, which can cause low blood pressure. This is why you may experience symptoms like breathlessness, dizziness, tiredness and even fainting. 

When to see a doctor

If you experience any of the following symptoms, you should arrange to see a GP:

  • Chest pain which comes and goes 
  • Heartbeats which are routinely faster or slower than the normal resting rate of 60 to 100 BPM (particularly if you have other symptoms, such as dizziness or breathlessness)
  • You notice a sudden change in your heartbeat 

Atrial fibrillation shares symptoms with several other heart conditions, so if you experience symptoms, you should arrange to see a doctor as soon as possible so that a proper diagnosis can be made. HCA UK offers same-day and next-day GP appointments.

If you experience chest pain which:

  • Spreads to your arms, back, neck or jaw
  • Makes your chest feel tight or heavy
  • Begins with breathlessness, sweating and / or feeling or being sick
  • Does not go away after more than 15 minutes

then it could be a sign of a heart attack. Call emergency services immediately.

Need to know

  • Potential treatment options icon plus

    If you are diagnosed with atrial fibrillation, then there are several different treatment options available. For some patients, treating the underlying cause of AF (such as an overactive thyroid) is sufficient, and no further treatment is necessary. However, most people will require treatment for AF. Your doctor will advise you about which is the best course of treatment for you, depending on your age, your general health, the type and cause of your atrial fibrillation and any other medical conditions you may have.

    Medication for atrial fibrillation may include:

    • Flecainide: to help restore normal heart rhythm
    • Beta blockers such as bisoprolol or atenolol: to slow the heart rate down and help restore normal heart rhythm 
    • Calcium channel blockers such as verapamil or diltiazem: these reduce your resting heart rate to below 90 BPM
    • Digoxin: this lowers your heart rate further 

    Medication side effects:

    Like most medications, some of these medicines can have unwanted side effects. Beta blockers can cause tiredness, cold hands and feet, low blood pressure, nightmares and impotence. Flecainide can make you feel sick, and occasionally causes heart rhythm disorders. Verapamil can cause constipation, low blood pressure, ankle swelling and in rare cases, heart failure.

    If you are at risk of a stroke, then your doctor may also prescribe an anticoagulant (to stop your blood from clotting) such as warfarin, dabigatran, rivaroxaban, apixaban or edoxaban. If you are prescribed an anticoagulant, you will need to have regular blood tests and may be at increased risk of bleeding. If you are worried about the possible side effects of any of these medications, then speak to your GP. 

    Electrical cardioversion
    In some cases, a procedure known as electrical cardioversion may be recommended to try and restore a normal heart rhythm. Electrical cardioversion can be either external or internal. In external cardioversion, large sticky pads will be placed on your front and back. These are then connected to a defibrillator machine, which gives your heart a small, controlled electric shock to make it beat normally again. For internal cardioversion, you'll be given local anaesthetic to numb your groin. A small tube will then be inserted into the vein at the top of your leg, to allow a fine wire to be threaded into your heart. This wire is connected to a defibrillator machine, which will deliver an internal electric shock.

    Catheter ablation
    Catheter ablation can be carried out under local or general anaesthetic. A small, flexible tube is inserted into a vein (or veins) at the top of your leg, and fine wires (catheters) are guided through the tube and into your heart. Once the area of tissue in your heart which is causing the atrial fibrillation is identified, it is destroyed using a beam of radiofrequency energy, or by freezing. This procedure corrects your heartbeat, so that it beats more regularly.

    If medication and other procedures are unsuccessful in treating your atrial fibrillation, then your doctor may suggest fitting a pacemaker. Pacemakers are smaller than a matchbox, and are usually fitted inside your chest below the collarbone. They work by sending out an electrical signal which can help regulate an irregular heartbeat.

  • Complications of AF icon plus

    In some cases, atrial fibrillation causes serious health problems. If you have AF, you are at greater risk of:


    An irregular rhythm in the upper chambers of the heart (the atria) can cause blood clots to form. In some cases, these clots travel from the heart to the brain, blocking blood flow and causing a stroke. If you have atrial fibrillation, you are 5 times more likely to have a stroke than people without the condition. 

    Heart failure

     In rare cases, atrial fibrillation which is not controlled can lead to heart failure. This is because the excess strain placed on the heart muscle by AF causes it to weaken, until it is unable to pump sufficient blood around your body. 

    Atrial fibrillation can have serious health consequences. That’s why it’s important to get a proper diagnosis from a doctor as soon as possible, so you can receive the treatment that you need.

Preventing Atrial fibrillation

It’s not always possible to prevent atrial fibrillation, particularly if it is caused by an underlying health problem. However, there are several steps that you can take to reduce your risk of atrial fibrillation. These include:

  • Giving up smoking 
  • Reducing your caffeine intake (tea, coffee and several energy drinks contain caffeine) 
  • Losing weight (if you are overweight)
  • Eating a healthy diet: a qualified nutritionist will be able to advise you on a heart-healthy diet (rich in fresh fruit, vegetables and pulses, and low in saturated fats)
  • Getting plenty of exercise
  • Avoiding excessive stress and anger, which are linked to heart rhythm problems
  • Controlling your cholesterol levels and blood pressure (with regular checks and treatment if necessary)

Our locations

From complex catheter lab procedures to tests, diagnostic procedures and cardiac rehab, we provide exceptional cardiac care across our network of hospitals, outpatient centres and specialist clinics.

Request a cardiac appointment

If heart symptoms are affecting your quality of life, we’re here to help. Our heart team is available to book an appointment with a cardiac specialist.

Call us today

020 7616 4988
This content is intended for general information only and does not replace the need for personal advice from a qualified health professional.
back to top