Atrial Fibrillation (also known as AFib or AF) is a common heart rhythm problem. It can make you feel uncomfortable, but AF itself usually isn’t life-threatening. That is, unless it goes undetected or is not treated. This puts you at risk of developing blood clots, which has serious health implications. 

So, it’s important to detect and treat AF promptly. There are innovative treatments available that can deal with AF and help you to live a normal life. 

In this guide we explain: 

  • What causes AF
  • How doctors can detect it
  • How the treatments work and how effective they are

We also provide aftercare information to make sure your recovery continues.

Contents: 

What is atrial fibrillation?

Heart conditions such as atrial fibrillation result in an irregular and often abnormally fast heart rate.

Nearly 1.4 million people in the UK have AF, making it the most common heart rhythm disturbance.

So, what does AF mean in medical terms? AF is an abnormal heart rhythm that affects the heart’s two upper chambers (the atria). 

If the heartbeats irregularly because of AF, blood can pool in the heart, leading to clots. Developing blood clots increases the risk of stroke and other heart-related complications.

Adults of all ages can develop AF. It’s more common in older adults and it affects more men than women.

AF is also found in many people with conditions such as: 

  • High blood pressure (hypertension)
  • Atherosclerosis (when arteries become clogged with fatty substances)
  • Abnormal heart valves.

Explore this playlist to learn more about what atrial fibrillation is and how it differs from atrial flutter.

Read on to learn about atrial fibrillation symptoms to look for.

Symptoms of atrial fibrillation

In some cases, AF does not cause noticeable symptoms, especially in older people.

Those who find out they have irregular heart rhythms are often diagnosed after having a test for another issue.

When you’re resting, your heart rate should be between 60 and 100 beats per minute. If you wish to measure your heart rate, check your wrist or neck to feel the pulse.

It’s common to experience irregular and sometimes a very fast heart rate when you have AF. In some cases it can exceed 100 beats a minute. This may lead to dizziness, shortness of breath, pain in the chest and fatigue.

Your heart may pound, quiver, or beat irregularly if you experience heart palpitations. These sensations may last a few seconds or several minutes.

Symptoms can include:

  • Chest Pain
  • Confusion
  • Dizziness
  • Exercising is difficult
  • Fainting
  • Fatigue
  • Heart palpitations 
  • Lightheadedness
  • Shortness of breath
  • Weakness

You may experience these symptoms intermittently, depending on the severity of your condition.

Left untreated, AF may lead to potentially life threatening complications, which we detail below. 

Important note

  • If you have symptoms of an irregular heart rhythm, talk to your doctor or call 111
  • If you or someone near you may be having a stroke, heart attack or cardiac arrest, call 999 immediately.

Explore this playlist

to learn what atrial fibrillation feels like.

Is atrial fibrillation a serious condition?

AF is a potentially serious condition. While not fatal itself, this disorder may cause an increased risk of stroke and heart failure. It is possible to live a normal, active life with AF if you receive the right medical care.

During episodes of AF, the heart beats differently, reducing its efficiency.

Stroke

There is a risk of blood clots forming when the upper chambers of the heart (atria) don’t pump effectively. In some cases, the clots travel to the lower chambers of the heart (the ventricles) and get pumped into the lungs or circulate through the body.

The cause of a stroke is a clot blocking an artery in the brain. Strokes are five times more likely to happen in individuals with AF.

The likelihood of a blood clot depends various factors, including:

  • Whether you have high blood pressure (hypertension)
  • Heart failure (see below)
  • Diabetes
  • Or a past history of blood clots.

Explore this playlist to learn more about atrial fibrillation and stroke.

Heart failure

After prolonged periods of AF, your heart may start to weaken. Heart failure can develop as a result when your heart cannot pump blood as effectively around your body.

Heart failure typically develops over time, so it may take time for the signs to appear.

Heart failure and a heart attack are both a type of heart disease. While they share some common causes, they are different things. 

Both are different to cardiac arrest, which is when the heart malfunctions and stops completely. This may take place after a heart attack or it could happen suddenly and unexpectedly. 

What causes atrial fibrillation?

During a normal beat, the heart’s walls tighten and squeeze (contract) to force blood throughout the body.

Afterwards, the muscles relax so that blood can return to the heart. The process repeats with every heartbeat.

In atrial fibrillation the upper chambers of the heart (the atria) contract randomly. When this occurs too quickly, the heart muscle cannot do its job of relaxing between contractions. In turn, the heart performs less efficiently.

Atrial fibrillation happens due to the sudden firing of abnormal electrical impulses in the atria. These impulses alter the heart’s natural rhythm, which can no longer control the heartbeat. This results in an abnormal pulse rate.

People with long-term illnesses like heart disease, diabetes, or obesity may experience AF. Its precise cause is not yet understood.

Other heart conditions may cause AF, including:

  • Atherosclerosis (clogging of the arteries)
  • Cardiomyopathy (diseases affecting the heart muscle)
  • Congenital heart disease (a heart problem present at birth)
  • Heart valve disease (often connected to the other conditions listed here)
  • High blood pressure (also called hypertension)
  • Pericarditis (inflammation around the heart)

The following conditions are also linked to AF:

  • Anaemia
  • Asthma
  • Carbon monoxide poisoning
  • Chronic kidney disease
  • Chronic obstructive pulmonary disease (COPD)
  • Lung cancer
  • Overactive thyroid gland (hyperthyroidism)
  • Pneumonia
  • Pulmonary embolism
  • Type 2 diabetes

Certain situations may trigger AF, such as

  • Being overweight
  • Drinking caffeine-rich drinks, such as tea, coffee, or energy drinks
  • Drug use, especially amphetamines and cocaine
  • Excessive drinking, especially binge drinking
  • Psychological and physical stress
  • Smoking
  • Taking some kinds of medication

Explore this playlist to learn more about the causes of atrial fibrillation.

Atrial flutter is a different but similar condition to atrial fibrillation. It shares the same symptoms, causes, and potential complications. The main difference is that atrial flutter has a more orderly rhythm. It’s possible to have both atrial flutter and atrial fibrillation.

How to restore normal heart rhythm

The way we treat your AF depends on the type, length and severity of the condition. After determining your stroke risk and treating it, we will then decide together how to manage your AF.

There are two main treatment approaches:

  • Controlling your AF rate (helping to control the rate of your blood flow)
  • Control your heart’s rhythm (this helps your heart to stay in rhythm)

The most common treatment for AF is medication. You’ll either need to take the medication regularly or only when you feel symptoms. We will tell you what approach you should take.

The following medicines can help reduce the frequency of irregular heartbeats:

  • Beta blockers
  • Sodium channel blockers 

We may recommend a different prescription if a particular medication does not work or if its side effects are difficult to manage.

The goal of controlling the heartbeat rate is to keep it beneath 90 beats per minute while at rest.

We may prescribe a beta blocker (examples include bisoprolol and atenolol). Or a sodium channel blocker (such as flecainide). Or a calcium channel blocker (examples are verapamil or diltiazem).

If those options are not fully effective, we may use digoxin. The medication slows the transmission of electrical currents from the atria to the ventricles.

For cases where medication does not help, we will consider non-invasive or minimally invasive clinical procedures. We explain the treatment options for AF in more detail below. 

Explore this playlist to learn more about the medications available for atrial fibrillation.

Atrial fibrillation treatment options

Finding out what causes atrial fibrillation is the first step. 

For example, if we find an overactive thyroid gland (hyperthyroidism) is the reason for your AF, then treating that condition is also likely to relieve your AF symptoms. 

We will normally confirm a diagnosis of AF using one or more of the following tests:  

  • An electrocardiogram (ECG) is a quick test using sensors placed on your chest to measure your heart’s electrical activity rhythm
  • An echocardiogram is an ultrasound scan of the heart and its valves to assess the structure and performance
  • A chest X-ray can help us detect lung issues that might contribute to atrial fibrillation
  • Blood tests can show if you have anaemia, kidney disease or hyperthyroidism.

Explore this playlist to learn more about how atrial fibrillation is diagnosed.

If the tests find no underlying cause, the treatments for AF include:

  • Medicines that treat AF by controlling heart rate or rhythm
  • Medicines to reduce stroke risk
  • Cardioversion (electrical rhythm control)
  • Catheter ablation 
  • Pacemaker

Explore this playlist to learn more about AF treatments.


Read on to find out what each of these options involves.  

Which treatment is right for you?

Our team will work closely with you to determine which treatment is most suitable and appropriate for you. 

The things that we will need to consider include:

  • How old you are
  • Your general health
  • The type of AF that needs treating
  • What symptoms you are experiencing
  • Any reversible underlying medical conditions or risk factors that contribute to AF

Medicines to reduce stroke risk

You are often prescribed anticoagulants if you have a heart condition like atrial fibrillation.

They are a way to reduce your risk of stroke (and ‘mini-strokes’ or TIAs) because they help to prevent blood clots from forming. They are also used to cut the risk of heart attacks, deep vein thrombosis (DVT) and pulmonary embolism (a blocked artery in the lungs).

Blood clots normally help you because they create a seal to stop bleeding from wounds. But when they form in the wrong place, they can cause blockages in blood vessels and reduce blood flow to essential organs like the brain, heart, or lungs.

Anticoagulants come in a variety of forms. In general they alter the process which the body uses to make the blood clot. Some people call them ‘blood thinners’ though this is not technically correct. 

Anticoagulants also work differently to antiplatelet medicines (aspirin is one of these) but doctors may prescribe them for similar reasons. 

A common anticoagulant is warfarin. You should take care to check that any other medicines you take are safe to have with warfarin. This is to avoid potentially serious interactions. 

People taking warfarin should also avoid alcohol, cranberry juice and grapefruit juice. You will also need regular blood tests to keep track of whether your dose is correct. 

Anticoagulants developed more recently may have fewer interactions, if any. And some do not require ongoing blood screening. You may see these referred to collectively as new or novel oral anticoagulants (NOACs).

In most cases, the benefits of anticoagulation outweigh the risks of bleeding. You should discuss all the available options in detail with your doctor, as well as the risks and benefits associated with each. 

Medicines that treat AF by controlling heart rate or rhythm

Certain medications treat AF by either controlling the rate of your heartbeat or your cardiac rhythm. 

Rate-control drugs work on the electrical impulses in your heart to ensure that it doesn’t beat too fast. As the heart rate goes slower and has more efficiency, the AF symptoms should reduce too.

The type of rate-control medicine prescribed depends on your symptoms, how fast your heart rate is, any other medical conditions, and what your personal preferences are. 

The kinds of medications that act as heart rate-control treatment include: 

  • A standard beta-blocker (which slows down your heart rate)
  • A calcium-channel blocker (which lowers blood pressure and reduces strain on your heart).
  • A cardiac glycoside such as digoxin. This is an alternative treatment for heart problems in case the doctor finds that you need further rate control.

Rhythm-control medications aim to restore a normal rhythm to your heart (doctors call this sinus rhythm). They are also known as antiarrhythmic drugs. The main options are: 

  • Sodium channel blockers (or ‘class I’ antiarrhythmics such as flecainide)
  • Beta blockers (or ‘class II’ antiarrhythmics)
  • Potassium channel blockers (or ‘class III’  antiarrhythmics such as amiodarone and dronedarone).

Side effects may occur with antiarrhythmics, as they can with any medicine. The potential side effects of antiarrhythmics typically include:

  • Class I – digestive upset and heart rhythm interruptions
  • Class II – fatigue, cold hands or feet, impotence, sleep disturbances
  • Class III – stomach upsets, disruption to liver and thyroid function, low blood pressure, swollen ankles.

Cardioversion 

Cardioversion is a non-invasive treatment where the heart receives controlled electric shocks to restore a normal rhythm. We do this via electrodes placed on the chest, with the patient under sedation.

Cardioversion is suitable for many people with AF but it is not always successful. You may need another cardioversion treatment a few weeks or months later if symptoms come back. 

In the longer term, we may suggest a different treatment. 

Catheter ablation 

Catheter ablation is a minimally invasive procedure that uses very thin catheters inserted into a blood vessel. We use the catheters to locate and then target the diseased parts of the heart tissue by heating it with radiofrequency energy or freezing it. This creates scar tissue in precise areas which blocks the abnormal electrical signals that cause AF. We then remove the catheters.

We may perform an ablation procedure if options such as medication and cardioversion were unsuccessful.  

This is a low-risk treatment. Sometimes people have bleeding, bruising or develop an infection at the catheter insertion point. There is a slight risk that normal electrical pathways in the heart become altered by the ablation. We will check you carefully and, if this is the case, we may recommend having a pacemaker fitted. 

Explore this playlist to learn more what you can expect from a catheter ablation procedure.

Pacemaker

A pacemaker is a small artificial implant to ensure that your heart doesn’t beat too slowly.

Usually, pacemaker fittings are minor surgical procedures performed under local anaesthesia.

A doctor might use this treatment if medication is ineffective or unsuitable, or if needed to maintain a regular heart rate after ablation treatment. The majority of these cases involve people aged over 80.

Explore this playlist to learn more about how pacemakers can treat atrial fibrillation.

How to prepare for atrial fibrillation treatment

Cardioversion

People experiencing atrial fibrillation for more than a couple of days could have an increased risk of clotting after cardioversion treatment.

In this situation you will need to take an anticoagulant medication for three to four weeks before cardioversion. 

You should carry on taking your regular medications unless told otherwise. 

On the morning of the cardioversion, we may tell you not to take any calcium channel blockers/beta-blockers. This helps prevent bradycardia (a heart rate that is very slow) after the procedure.

Catheter ablation 

Our team will let you know if you need to stop taking any medications in advance, and when you leave the hospital. This advice will vary from patient to patient, and we’ll tell you at every stage what each drug aims to do.

You may start a course of warfarin (anticoagulant medication) six weeks before the procedure, if you are not taking it already. 

If you regularly take one of the new oral anticoagulants (NOACs), you may need to change it temporarily to warfarin if it’s suitable for you. 

You should also have regular blood tests in the lead up to the procedure to check how much time it takes for your blood to clot. We call this test an ‘international normalized ratio’ or INR.

We will tell you if you need to stop any of your medications before the ablation procedure. As with cardioversion, you will probably not take certain heart condition medications on the day. This is to prevent low blood pressure while the procedure takes place. 

Explore this playlist to learn about the success rates of catheter ablation.

What to expect on the day

Cardioversion

Cardioversions usually take place in a hospital so your heart can be carefully monitored.

For the procedure  you’ll have a short-acting anaesthetic or heavy sedative. This means you will be asleep and feel no pain. 

The treatment lasts for about half an hour. We stick electrodes onto your chest and then connect them to a defibrillator. This is a machine that produces one or more controlled electric shocks that pass through your chest wall. 

The defibrillator also shows a reading of your heart rhythm during the procedure. From this we can tell immediately if your heart now has a normal rhythm. 

Catheter ablation 

You will need to have an empty stomach when we give you the anaesthetic, so you cannot eat in the six hours before the procedure. 

You may have a general anaesthetic, or a local anaesthetic with sedation to make you more comfortable. The treatment is usually quick or, depending on your condition, it could take up to three or four hours. You will need to remain still and lie flat during this time. 

The catheters for cardiac ablation treatment are thin, soft wires. We pass them through a small cut (usually in the groin or arm) and guide them precisely along a vein or artery and into your heart.

The first stage is to measure electrical activity in the heart, known as an electrophysiological (EP) study. Sometimes we’ll do this in an earlier, separate procedure to the ablation. 

When we find the source of the AF, we send high-frequency radio waves along the catheter to treat the area with heat (sometimes it’s frozen instead, which we call cryoablation). This process aims to block the abnormal electrical signals causing AF. 

After performing the ablation, we remove all of the catheters. 

Explore this playlist to learn more about the risks of ablation.

Pacemaker

It’s a relatively simple surgical process to implant a pacemaker. Preparation usually involves a few general health and heart checks before surgery. Normally you’ll have a local anaesthetic and remain awake during the operation. 

A pacemaker is basically a small electrical generator. It’s implanted beneath your skin near your collarbone on the left side of your chest. The device has a wire that we guide into place in your heart via a blood vessel during the fitting. 

A procedure like this normally takes about an hour. Generally, you will be able to leave the hospital later that day or the day after.

Explore this playlist to learn more about pacemakers.

Recovery and aftercare

Cardioversion  

You will usually only need a few hours in the hospital although some people may need to stay overnight if their medical condition requires it.

In most cases, complications after cardioversion aren’t serious and will be temporary.

A fall in your blood pressure after cardioversion may cause headaches and dizziness. You may also feel slight discomfort where we had placed the electrodes. It is also common for the anesthetic to make patients nauseous.

Some people may have blood clots in their heart which could cause a stroke, if they move during the procedure. 

For people at risk of stroke, the doctor may use an echocardiogram test to check for blood clots. You will usually take an anticoagulant for at least a month afterwards. This aims to reduce your stroke risk, as well as the chances of your AF returning. We will review your situation a few weeks after cardioversion treatment. 

Catheter ablation 

After the ablation is complete, we take out all of the catheters. There may be small amounts of bleeding at the incision point. Nurses or doctors will apply pressure to the area for a short time to stop any bleeding. Feeling tender and experiencing some bruising is normal.

Having catheter ablation normally leads to a quick recovery. After the next day, you should be able to do most of what you normally do.

You should avoid driving for the first two days and any heavy lifting or physical exertion for two weeks.

It’s likely that you will need a second ablation if your symptoms don’t improve or if they return a few weeks after the first one. At this point we can discuss your options with you.

Explore this playlist to learn more about what to expect after your procedure.

Pacemaker  

The usual recommendation is to limit strenuous activity for up to six weeks following the installation of a pacemaker. There should be no problem doing most activities – including sports – after that.

Initially, you may be very aware of the pacemaker’s presence under your skin, but you will soon become accustomed to it. The majority of pacemakers record information about your heart rhythm. We can use this to see how you are getting on when you come in for a regular checkup.

Explore this playlist to learn more about recovery from a pacemaker procedure.

If you need treatment for atrial fibrillation, book a consultation with one of our specialists to discuss your options.