Atrial fibrillation

Atrial fibrillation is a heart condition that causes an irregular and often abnormally fast heart rate. Speak to your GP immediately or contact GP out of hours service if you notice a sudden change in your heartbeat, that makes you feel unwell, or if you have chest pain.

Heart rate

A normal heart rate should be regular and between 60 and 100 beats a minute when you're resting.

You can measure your heart rate by feeling the pulse in your neck or wrist.

In atrial fibrillation, the heart rate is irregular and can sometimes be very fast. In some cases, it can be considerably higher than 100 beats a minute.

Symptoms of atrial fibrillation

Some people with atrial fibrillation, particularly older people, do not have any symptoms.

The abnormality in heart rhythm is often only discovered during routine tests or investigations for another condition.

People often link tiredness and feeling lethargic to ageing. But once normal rhythm is restored, they realise these symptoms were caused by atrial fibrillation.

Heart palpitations

The most obvious symptom of atrial fibrillation is heart palpitations. This is where the heart feels like it's pounding, fluttering or beating irregularly, often for a few seconds or possibly a few minutes.

As well as an irregular heartbeat, your heart may also beat very fast (often much higher than 100 beats per minute).

You can work out your heart rate by checking the pulse in your neck or wrist.

Other symptoms you may experience if you have atrial fibrillation include:

The way the heart beats in atrial fibrillation reduces the heart's performance and efficiency.

This can lead to low blood pressure (hypotension) and heart failure.

Electrocardiogram

An electrocardiogram (ECG) can be used to confirm a diagnosis of atrial fibrillation. An ECG is a test that records the rhythm and electrical activity of your heart.

When to see your GP

You should make an appointment to see your GP if:

  • you notice a change in your heartbeat which does not go away, or keeps happening
  • your heart rate is consistently lower than 60 or above 100, particularly if you're experiencing other symptoms of atrial fibrillation, (see above)

Speak to your GP urgently or contact GP out of hours service if you have palpitations and feel unwell, or if you have chest pain. If you are unable to contact them, call 999.

About atrial fibrillation

When the heart beats normally, its muscular walls contract (tighten and squeeze) to force blood out and around the body. They then relax so the heart can fill with blood again. This process is repeated every time the heart beats.

In atrial fibrillation abnormal electrical impulses suddenly start firing in the atria. This causes you to have a highly irregular pulse rate.

The heart's upper chambers (atria) contract randomly and sometimes so fast that the heart muscle cannot relax properly between contractions. This reduces the blood flow, from the heart, round the body. This can cause symptoms depending on how much the flow is reduced.

Causes of atrial fibrillation

Atrial fibrillation is the most common heart rhythm disturbance. Usually the cause is known but sometimes it is not fully understood. It can affect adults of any age, but it's more common in older people. It affects about 7 in 100 people aged over 65. More men than women have atrial fibrillation. 

Atrial fibrillation is more likely to occur in people with other conditions including:

It may be triggered by certain situations, such as drinking too much alcohol or smoking, or taking some medication.

Treating atrial fibrillation

Atrial fibrillation is not usually life threatening. But the condition can be uncomfortable and often requires treatment.

Treatment may involve: 

  • medication to prevent a stroke (people with atrial fibrillation are more at risk of having a stroke)
  • medication to control the heart rate or rhythm
  • cardioversion – where the heart is given a controlled electric shock to restore normal rhythm
  • catheter ablation – where the area inside the heart that's causing the abnormal heart rhythm is destroyed using radiofrequency energy; afterwards you may then need to have a pacemaker fitted to help your heart beat regularly

Atrial flutter

Atrial flutter is less common than atrial fibrillation, but shares the same symptoms, causes and possible complications.

About a third of people with atrial flutter also have atrial fibrillation.

Atrial flutter is similar to atrial fibrillation, but the rhythm in the atria is more organised and less chaotic than the abnormal patterns caused by atrial fibrillation.

Treatment for atrial flutter is also slightly different. Catheter ablation is considered to be the best treatment for atrial flutter. Medication is often the first treatment used for atrial fibrillation.

The information on this page has been adapted from original content from the NHS website.

For further information see terms and conditions.

Health conditions A to Z

Search by health condition or symptoms

Or find conditions beginning with …

Share this page

What do you want to do?
What is your question about?
Do you want a reply?
Your email address
To reply to you, we need your email address
Your feedback

We will not reply to your feedback.  Don't include any personal or financial information, for example National Insurance, credit card numbers, or phone numbers.

This feedback form is for issues with the nidirect website only.

You can use it to report a problem or suggest an improvement to a webpage.

If you have a question about a government service or policy, you should contact the relevant government organisation directly as we don’t have access to information about you held by government departments.

You must be aged 13 years or older - if you’re younger, ask someone with parental responsibility to send the feedback for you.

The nidirect privacy notice applies to any information you send on this feedback form.

Don't include any personal or financial information, for example National Insurance, credit card numbers, or phone numbers.

Plain text only, 750 characters maximum.
Plain text only, 750 characters maximum.

What to do next

Comments or queries about angling can be emailed to anglingcorrespondence@daera-ni.gov.uk 

What to do next

If you have a comment or query about benefits, you will need to contact the government department or agency which handles that benefit.  Contacts for common benefits are listed below.

Carer's Allowance

Call 0800 587 0912
Email 
dcs.incomingpostteamdhc2@nissa.gsi.gov.uk

Discretionary support / Short-term benefit advance

Call 0800 587 2750 
Email 
customerservice.unit@communities-ni.gov.uk

Disability Living Allowance

Call 0800 587 0912 
Email dcs.incomingpostteamdhc2@nissa.gsi.gov.uk

Employment and Support Allowance

Call 0800 587 1377

Jobseeker’s Allowance

Contact your local Jobs & Benefits office

Personal Independence Payment

Call 0800 587 0932

If your query is about another benefit, select ‘Other’ from the drop-down menu above.

What to do next

Comments or queries about the Blue Badge scheme can be emailed to bluebadges@infrastructure-ni.gov.uk or you can also call 0300 200 7818.

What to do next

For queries or advice about careers, contact the Careers Service.

What to do next

For queries or advice about Child Maintenance, contact the Child Maintenance Service.

What to do next

For queries or advice about claiming compensation due to a road problem, contact DFI Roads claim unit.

What to do next

For queries or advice about criminal record checks, email ani@accessni.gov.uk

What to do next

Application and payment queries can be emailed to ema_ni@slc.co.uk

What to do next

For queries or advice about employment rights, contact the Labour Relations Agency.

What to do next

For queries or advice about birth, death, marriage and civil partnership certificates and research, contact the General Register Office Northern Ireland (GRONI) by email gro_nisra@finance-ni.gov.uk

What to do next

For queries about:

If your query is about another topic, select ‘Other’ from the drop-down menu above.

What to do next

For queries or advice about passports, contact HM Passport Office.

What to do next

For queries or advice about Penalty Charge Notices (PCNs), including parking tickets and bus lane PCNs, email dcu@infrastructure-ni.gov.uk

What to do next

For queries or advice about pensions, contact the Northern Ireland Pension Centre.

What to do next

If you wish to report a problem with a road or street you can do so online in this section.

If you wish to check on a problem or fault you have already reported, contact DfI Roads.

What to do next

For queries or advice about historical, social or cultural records relating to Northern Ireland, use the Public Record Office of Northern Ireland (PRONI) enquiry service.

What to do next

For queries or advice about rates, email LPSCustomerTeam@lpsni.gov.uk

What to do next

For queries or advice about  60+ and Senior Citizen SmartPasses (which can be used to get concessionary travel on public transport), contact Smartpass - Translink.