Atrial Fibrillation

Atrial Fibrillation, what is it?

What is atrial fibrillation? 0:47
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Atrial Fibrillation FAQs

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Overview  |  Stroke risk  |  Symptoms  |  Causes  |  Risk  |  Diagnosis  |  Treatment


What is atrial fibrillation?

Atrial fibrillation (AF or A-Fib) is a heart rhythm disorder that causes an irregular heartbeat (arrhythmia). It occurs due to electrical activity problems in the heart.

There are four main types:

  • Occasional (Paroxysmal) – A few minutes to 48 hours
  • Persistent – Longer than a week
  • Long-standing persistent – Lasts a year or more
  • Permanent – Requires life-long management

During atrial fibrillation, electrical impulses in your atria (the heart’s upper chambers) fire irregularly instead of consistently. The atria are then out of sync with the ventricles (lower chambers). You might have an abnormally fast heart rate – over 140 beats per minute while resting.

Stroke risk

An irregular heartbeat can cause blood to pool in the atria, which may lead to a blood clot. As a result, stroke risk is five times higher than the average person in people with AF.

Your risk is also higher if you have high blood pressure, diabetes, and heart failure. To reduce your stroke risk, we may recommend blood-thinning medications.


Atrial fibrillation can have symptoms that are anywhere from unnoticeable to severe. Older people, in particular, are more likely to experience no symptoms and the condition is often first noticed during a routine check-up.

Symptoms in the chest include:

If you experience sudden chest pain or chest tightness, seek emergency help. Chest pain can be a sign of a heart attack, alongside nausea, vomiting, and sweating.

You may also experience symptoms whilst going about daily activities, such as:

  • Breathlessness
  • Tiredness/ fatigue
  • Difficulty exercising
  • Feeling weak or confused
  • Dizziness, lightheadedness, or fainting


Symptoms at night

If you have obstructive sleep apnoea (OSA) or vagal-induced AF, your symptoms may worsen at night. You might wake up feeling anxious or have a strange sensation in your chest. A bed partner may notice symptoms you don’t, such as heavy breathing while sleeping and night sweats. 

If you have OSA, you might snore loudly, wake with a dry mouth or headache, and feel tired during the day. Up to 80% of people with atrial fibrillation have OSA, which can worsen symptoms if we don’t treat it.

Some people experience fewer symptoms sleeping on their side. Though, we don’t consider either side better than the other. You may benefit from doing yoga or deep breathing exercises.


Atrial fibrillation symptoms0:26


Conditions that affect the heart’s structure can cause atrial fibrillation, such as coronary artery disease and heart valve problems. A congenital heart defect, lung disease, and a heart attack can also lead to the condition.

Anxiety, smoking, and drinking a lot of alcohol or caffeine can trigger an instance of AF (an episode). Illegal drugs, such as amphetamines or cocaine, can also contribute to this.


What causes atrial fibrillation?0:27

Risk factors

While anyone can experience atrial fibrillation, certain factors can increase your risk.

These include factors out of your control, for example:

  • Tall height
  • Male gender
  • Older age (over 50)
  • Family history – especially in younger cases

Health issues, such as:

  • Obesity
  • Diabetes
  • Chronic kidney disease
  • High blood pressure
  • Previous heart surgery
  • High stress levels – physical and mental
  • Thyroid disease, such as hyperthyroidism

And certain heart and lung conditions:

  • Asthma
  • Heart failure
  • Lung cancer
  • Pulmonary embolism
  • Chronic obstructive pulmonary disease (COPD)

Atrial fibrillation is not limited to those with previous or existing health conditions. It can affect those who are physically fit and exercise regularly. If you experience an irregular heartbeat or concerning symptoms, speak to your doctor or book an appointment with a cardiologist. 


Diagnosis starts by discussing your symptoms and general health and checking for an erratic pulse. Then, we will refer you for an electrocardiogram (ECG), which records the heart’s electrical activity.

Some people need to wear a small heart monitor (a Holter monitor) for a few days to check their heart over time. We may recommend this if we detect no abnormalities during a standard ECG or if symptoms occur in brief bouts at various times of the day or night.

We might also send you for other tests, such as blood tests, a chest X-ray, and an echocardiogram (an ultrasound scan of the heart). This allows us to check for other conditions linked with AF or causing your symptoms.

Atrial fibrillation vs atrial flutter

Atrial fibrillation is sometimes mistaken for a similar condition called atrial flutter, a similar condition. It is possible to have both conditions simultaneously. Dr Syed Ahsan explains the difference in our video below: Atrial flutter vs atrial fibrillation: what is the difference?


How is atrial fibrillation diagnosed?0:51


Atrial fibrillation treatment aims to control your heart rate and rhythm, as well as reduce your stroke risk. We will tailor your treatment plan around your general health, the type of AF you have, your age and symptoms. Any other conditions you have will also impact our treatment recommendations.

Treatment options include:

There are also lifestyle changes that you can make to prevent episodes, such as managing stress. We discuss these and the treatment options on our atrial fibrillation treatment page. Read our blog to learn more about lifestyle changes to help manage an arrhythmia.


What are the treatments available0:59

Book an appointment

If you’re experiencing symptoms of atrial fibrillation, seek specialist help. Our expert cardiologist will perform a series of tests to diagnose your condition and identify other problems. We will then form a treatment plan based on your needs and circumstances.

It is helpful to list your symptoms, their severity, and any triggers you’ve noticed. We’ll also discuss your family medical history, so it can help to bring a list of any known conditions of close family members.

Book a private consultation to prioritise your heart health and discover the cause of your symptoms.

Dr Syed

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