What is atrial fibrillation?
Atrial fibrillation, often shortened to AFib, is a heart condition that causes the heart to beat irregularly and often abnormally fast.
A healthy heart will beat with a steady, regular rhythm. If you have atrial fibrillation, the upper chambers of the heart (atria) beat irregularly – this leads to a decrease in heart function.
As well as making your heart beat irregularly, atrial fibrillation may also make your heart beat too fast. At rest, a normal heart rate is between 60 and 100 beats a minute; people with atrial fibrillation have a heart rate over 100 beats a minute.
How does atrial fibrillation occur?
The heart is made up of four chambers: two upper (atria) and two lower (ventricles). An electrical system helps keep the heart beating at a regular, steady rhythm.
The heart’s natural pacemaker (the sino-atrial node) is located in the right atrium. This node sends the signals that allow your heart to contract; the signals travel to the left atrium, then to the left and right ventricles. The atria contract to move blood into the ventricles, while the ventricles contract to move blood out to the body.
When you have atrial fibrillation, the heart receives signals from outside the sino-atrial node, causing the atria to quiver (fibrillate) in an irregular fashion. The ventricles receive these erratic signals and are unable to efficiently pump blood out to the body. These irregular contractions can also cause blood to pool in the heart.
If blood pools within the heart, it may start to clot. Most clots form inside the left atrium, because it has a pouch within the muscle wall (the left atrial appendage) where blood can become trapped. Clots have the potential to leave the heart and travel to the brain, causing a stroke – in fact, around 20% of all strokes in the UK are caused by atrial fibrillation.
Is atrial fibrillation heart failure?
Heart failure is when the heart becomes unable to pump blood properly around the body, meaning that your cells can’t receive the oxygen and nutrients they need. It can develop suddenly (acute) or gradually worsen over time (chronic).
Atrial fibrillation is not the same as heart failure. However, having atrial fibrillation can raise your risk of developing heart failure, alongside other heart-related complications.
How long can a person live with atrial fibrillation?
Untreated atrial fibrillation may lead to reduced life expectancy – this is because atrial fibrillation can raise your risk of heart failure, strokes, and more. However, most people who receive ongoing treatment for atrial fibrillation will lead long and healthy lives.
Atrial flutter vs atrial fibrillation
Atrial flutter is a type of abnormal heart rhythm (arrythmia) that causes the upper chambers of the heart (atria) to beat too quickly.
Atrial flutter is like atrial fibrillation. However, in atrial flutter, the heart rate is fast but regular; in atrial fibrillation, the heart rate is more erratic. It is possible to have episodes of both atrial flutter and atrial fibrillation.
Atrial fibrillation symptoms
If you have atrial fibrillation, you may feel that your heart beats irregularly and too fast, even if you’re at rest.
You may also experience other symptoms, including:
- heart palpitations (the sensation of your heart skipping a beat)
- chest pain
- tiredness
- shortness of breath
- dizziness
- feeling faint
- difficulty exercising
Some people do not experience any symptoms and their atrial fibrillation is only detected at a routine appointment.
Atrial fibrillation symptoms at night
Atrial fibrillation symptoms at night may differ from those experienced in the daytime – largely because you’re usually lying down and resting.
If you have atrial fibrillation symptoms at night, you may experience:
- frequent waking from sleep
- waking with an odd feeling in your chest
- feelings of anxiety
Atrial fibrillation causes
The causes of atrial fibrillation aren’t completely understood. It most often occurs in older people and those who have chronic conditions, such as heart disease, high blood pressure, or obesity.
However, some people who have atrial fibrillation don’t have any risk factors or pre-existing conditions. In these cases, their condition is known as lone atrial fibrillation.
Can stress cause atrial fibrillation?
Both stress and anxiety can contribute to atrial fibrillation, although they are not a direct cause of it.
Heightened emotional states can cause cardiac responses, such as heart palpitations when scared. It has been suggested that stress and anxiety can worsen episodes of atrial fibrillation in those who already have the condition.
Non-cardiac causes of atrial fibrillation
Atrial fibrillation can occur in some non-cardiac conditions, including:
- asthma
- overactive thyroid gland
- chronic obstructive pulmonary disorder (COPD)
- lung cancer
- type 2 diabetes
It may also be triggered by things like:
- consuming large amounts of alcohol or caffeine
- being overweight
- taking illegal drugs
- smoking
Tests for atrial fibrillation
There are various tests you may be recommended if you have suspected atrial fibrillation:
- electrocardiogram (ECG) – a test that measures the electrical signals of the heart (a snapshot at that time)
- 24-hour or 3-day Holter monitor – a test that measures electric signals of the heart of a longer period
- echocardiogram – a scan used to examine the heart and surrounding blood vessels
- chest X-ray – this may be carried out if you have a suspected lung problem that might be causing your atrial fibrillation
- blood tests – to check for other underlying causes of atrial fibrillation, such anaemia or an overactive thyroid gland
Atrial fibrillation medication
Some cases of atrial fibrillation can be controlled by medication called anti-arrhythmics, which help restore a normal heart rhythm and control the rate of your heartbeat.
You may also be given a type of medication, called anti-coagulants, to help prevent a stroke – this is because atrial fibrillation can raise your stroke risk. Anti-coagulants help stop the blood from clotting.
Catheter ablation for atrial fibrillation
Catheter ablation is a treatment used to correct certain types of abnormal heart rhythms. It works by either heating (radiofrequency ablation) or freezing (cryoablation) the area of the heart that’s causing the abnormal rhythm, creating scar tissue that blocks the electrical pathways. It can also destroy areas of the heart muscle that are responsible for triggering the abnormal rhythm.
During the procedure, thin, flexible tubes called catheters are passed through the blood vessels into the heart. Once the area to be treated is identified, any patches of abnormal tissue are destroyed. Patients are usually able to go home the same day, or after one night in hospital.
Hybrid ablation for atrial fibrillation
Hybrid ablation is an innovative new type of treatment for patients with persistent atrial fibrillation, which involves a combination of two procedures: keyhole surgery and catheter ablation. Ablation is used to destroy tissue inside the heart, while surgery destroys tissue on the outside of the heart.
The surgical portion of the treatment involves using a long, thin device called a pericardioscope, which has a tiny camera and light attached to one end. This allows the surgeon to effectively see the outside of the heart and enables them to destroy any fibrillation-causing tissues with greater precision.
In some cases, during the hybrid ablation procedure, your surgeon may choose to place a special clip or suture on a part of the heart called the left atrial appendage. This may help reduce your chances of having a stroke in the future.
At Cromwell Hospital, hybrid ablation is carried out jointly by Mr Aziz Momin, Consultant Cardiac Surgeon, and Dr Riyaz Kaba, Consultant Cardiologist – collectively they carried out the highest number of hybrid AF ablations in Europe in 2019, 2022, and 2023.
Cardioversion for atrial fibrillation
Cardioversion is a treatment that aims to return your abnormal heart rhythm to a regular state through the use of electrical signals. It may be suitable for certain types of atrial fibrillation.
During the procedure, you will be fitted with electrodes that are attached to your chest. Controlled electric shocks are then delivered to the heart via a defibrillator, which continuously monitors the heart rhythm throughout treatment.
Pacemaker for atrial fibrillation
A pacemaker is a small electronic device inserted into the chest to help control your heart rhythm. In some instances, it may be used as a treatment for atrial fibrillation – often for those who are older or do not respond to medication.
Inserting a pacemaker is a short and simple procedure that takes around 30 minutes to complete. Your surgeon will make a small incision just below the collarbone and insert the pacemaker into your chest, before feeding the pacemaker’s leads through a vein to your heart. Most patients stay in hospital overnight.
Atrial fibrillation treatment at Cromwell Hospital
If you require treatment for atrial fibrillation, the Heart and Lung Centre at Cromwell Hospital provides a comprehensive range of treatment options carried out by world-leading cardiac specialists. We are also one of the only private hospitals in the UK to provide minimally invasive (keyhole) cardiac surgery.
Patients at the Centre can benefit from our multidisciplinary approach to care, with input from cardiologists, cardiac surgeons, physiologists, and more. Every aspect of care is tailored to your unique needs, ensuring you feel supported throughout treatment.
About the consultants
Mr Aziz Momin graduated in medicine from King's College London and undertook surgical training at the Royal College of Surgeons of England. In 2013, he was appointed Consultant Cardiac Surgeon and Senior Lecturer at St. George's Hospital and Medical School, London. Mr Momin currently runs a new patient clinic and has a special interest in total arterial grafting, AF surgery, aortic surgery, and minimally invasive surgery.
View Mr Aziz Momin’s profile >
Dr Riyaz Kaba is a clinical academic Consultant Cardiologist and Cardiac Electrophysiologist at St George's, University of London, and Ashford and St Peter's Hospitals, Surrey, with an additional academic appointment at Royal Holloway, University of London. He has a special interest in arrhythmias and hosts the Surrey Atrial Fibrillation (AF) Meeting to enhance the clinical treatment and care of patients with atrial fibrillation and related conditions. Dr Kaba is the chief investigator of the HALT-AF (Hybrid AbLaTion of Atrial Fibrillation) trial.
View Dr Riyaz Kaba's profile >
Both consultants are members of the London Heart Partnership, a specialist cardiac group based at Cromwell Hospital.