What is Atrial Fibrillation?
Atrial fibrillation (AF) is a condition where the heart beats irregularly which is also known as an arrhythmia. In AF, the upper chambers of the heart (the atria) beat fast and chaotically instead of squeezing in a regular way, it is referred to as fibrillating or quivering. This makes the heartbeat irregular and can reduce how effectively the heart pumps blood.
When the heartbeat is irregular, blood can pool in the heart and this can lead to blood clots. If a clot travels to the brain it can cause a stroke. This is why AF is taken very seriously.
AF episodes can come and go, or the irregular rhythm can be there all the time. Some people feel AF straight away, while others have no symptoms and only find out when they have a test or a stroke.
Different types of Atrial Fibrillation
Doctors and physicians often describe AF in terms of how long it lasts and how often it returns.
A one-off AF event
Sometimes people experience a one-off episode of AF, for example after heavy drinking (“holiday heart”), severe illness, or major surgery. Even if AF seems to have settled, it is important to talk with your doctor about long-term risk and follow-up.
Occasional AF (Paroxysmal AF)
AF episodes start suddenly and then stop on their own. They may last from a few minutes but typically last for short durations.
Persistent AF
The irregular rhythm continues for longer than seven days and does not go back to normal on its own. Treatment such as medicines or a cardioversion procedure is usually needed.
Chronic or Permanent Atrial Fibrillation
The heart permanently has an irregular heartbeat, so AF has been present for a long time and attempts to restore a normal rhythm have not been successful or are not appropriate. The focus is on controlling heart rate and reducing stroke risk.
Causes of Atrial Fibrillation
There are many known causes for AF, typically around a disease or event which has an impact on the heart. Some of the known causes of AF are listed below, such as it becoming more common with age, but it can occur at younger ages, especially in women with other risk factors. However, it is also important to know sometimes no cause can be found for AF. Many people have another heart or health condition that puts extra strain on the heart.
Conditions and factors that can increase the risk of AF include:
- Family history or a genetic tendency to AF
- Heart valve problems where the flow of blood in the heart can be interrupted (for example, due to rheumatic heart disease)
- Heart failure a condition where the heart’s pumping function is impaired (the heart muscle is weak or stiff)
- High blood pressure (also known as hypertension)
- Coronary artery disease or a previous heart attack
- Cardiomyopathy or an enlarged heart
- Sleep apnoea
- Overactive thyroid gland (hyperthyroidism)
- Excess alcohol, especially “binge” drinking
- Recent heart surgery or major chest surgery
- Certain medicines and stimulants
Sometimes people with AF are undiagnosed because they have no obvious symptoms. Studies suggest that a substantial proportion of AF is “silent” and is only found when a person has a stroke or has an ECG for another reason.
How Common is AF, and What Does it Mean for Women?
AF is one of the most common heart rhythm problems worldwide. In Australia, the AIHW found that AF contributed to about 18,100 deaths (around one in ten deaths) in 2022 and was recorded as an underlying or associated cause on many death certificates.
Women are more likely to be diagnosed later. AF becomes more common with age, and many women are first diagnosed in their sixties or seventies.
Women with AF are more likely than men with AF to experience stroke, severe disability after stroke, and heart failure.
Women often have AF for longer before it is diagnosed, and are more likely to report fatigue, breathlessness and general “slowing down” rather than clear palpitations.
AF is an important contributor to the overall burden of cardiovascular disease in Australian women, alongside coronary heart disease and stroke.
Procedures such as ablation are performed less frequently in women.
For Aboriginal and Torres Strait Islander women, the burden of heart disease, stroke and other circulatory diseases is higher than for other Australian women. Hospitalisation rates for AF and its complications are higher, and risk factors such as rheumatic heart disease, hypertension and diabetes are more common.
Symptoms of Atrial Fibrillation
Sometimes AF causes no symptoms at all. When symptoms are present, they can be typical (what doctors expect) or atypical. Women are more likely to present with atypical symptoms, or to put symptoms down to stress, ageing, or “being unfit,” which can delay diagnosis. They also present after a longer duration of symptoms.
Typical symptoms
- A fast, fluttering or pounding heartbeat (palpitations)
- Irregular heartbeat that you can feel as “skipping,” “thudding” or “flip-flopping”
- Chest discomfort or chest pain
- Shortness of breath, especially on exertion or when lying flat
- Feeling light-headed or dizzy, or near-fainting
Atypical symptoms
- Unusual tiredness or loss of energy
- Weakness or reduced stamina
- Feeling “puffed” more easily with day-to-day activities
- Vague chest tightness, anxiety or feeling “on edge”
- Poor sleep or waking at night with a racing heart
Call 000 immediately if you have:
- Sudden chest pain or pressure
- Sudden weakness, difficulty speaking, facial droop, or loss of vision (possible stroke)
- Severe shortness of breath, fainting or collapse
Diagnosis of Atrial Fibrillation
AF is usually diagnosed with an electrocardiogram (ECG), a simple test that records the heart’s electrical activity. Sometimes a standard ECG in the clinic is enough to confirm AF. In other cases, your doctor may arrange:
- Ambulatory ECG monitoring (Holter monitor) worn for 24 hours or longer to capture intermittent episodes
- Event recorder or wearable device that records your heart rhythm during symptoms
- Blood tests to look for causes such as thyroid disease or electrolyte imbalance
- Echocardiogram (heart ultrasound) to look at the structure and pumping function of your heart
Managing AF and Reducing Stroke Risk
Treatment is tailored to each woman depending on age, symptoms, stroke risk, other health conditions and personal preferences. The goals of treatment are to reduce the risk of stroke, control heart rate, improve symptoms and, where appropriate, restore or maintain a normal rhythm. Also, to decrease symptoms and improve quality of life.
Medicines to reduce stroke risk
If you have AF, your doctor will assess your risk of stroke using a simple scoring system that includes age, sex, blood pressure, diabetes, heart failure and other factors. Many women with AF will be advised to take an anticoagulant medicine (sometimes called a “blood thinner”) to reduce the chance of a clot forming in the heart.
- Anticoagulants do not cure AF, but they are very effective at preventing stroke.
- Your doctor or pharmacist will explain how to take them safely and what blood tests or monitoring you may need.
- It is very important not to stop an anticoagulant suddenly without medical advice.
Medicines to help maintain a normal rhythm
In some cases, medicines are used to maintain or restore a normal (sinus) rhythm which often improves symptoms such as breathlessness and fatigue. These medicines can have side effects and may need regular blood tests or monitoring of the liver and thyroid. Your cardiologist will discuss whether rhythm-control medicines are suitable for you. These may include:
- Beta blockers
- Calcium channel blockers
- Other rate-controlling medicines as advised by your cardiologist
Cardioversion – a short procedure to restore normal rhythm
Cardioversion is a painless procedure which attempts to get your heart back to a normal rhythm. In a cardioversion, you are given a general anaesthetic (put to sleep) and gentle electric currents are sent to the heart to put it back to normal rhythm. It is usually a day procedure and is often recommended when symptoms are significant or AF is newly diagnosed. Many women find symptoms improve quickly after a successful cardioversion.
Catheter ablation – targeted treatment for the electrical triggers of AF
In a catheter ablation, thin catheters are passed through a vein into the heart, and heat or cold energy is used to isolate or destroy small areas of tissue that trigger AF. Ablation can significantly reduce symptoms and AF episodes, particularly in symptomatic women. Some women require more than one procedure, and your cardiologist will discuss the expected outcomes.
Pacemaker – used in select situations
A pacemaker is sometimes recommended when AF is associated with very slow heart rates or when certain ablation procedures are performed. It is a small device placed under the skin in the chest, with leads inside the heart and sends electrical signals to control the heart rate. It helps regulate the heartbeat and prevent symptoms such as dizziness or fainting. A pacemaker does not treat AF directly but supports the heart in maintaining a safe rhythm. Most people recover from the procedure within a few weeks of treatment.
Your cardiologist will explain the benefits and risks of each option and how they relate to your situation.
Living Well with AF
Many women with AF live active, fulfilling lives. Practical steps that can help include:
- Taking medicines exactly as prescribed
- Attending regular check-ups and asking about your stroke risk and blood pressure
- Limiting alcohol and avoiding binge drinking
- Not smoking
- Maintaining a healthy weight and being physically active most days of the week
- Treating conditions such as sleep apnoea, high blood pressure and diabetes
- Learning how to check your pulse and noticing if it feels irregular or unusually fast
If you feel that AF is affecting your mood, sleep, relationships or ability to work, it can help to talk with your doctor, a psychologist, or a peer support group.
What you need to know
Further information
- Expert Q&As - Atrial Fibrilation
- Fact sheet - Atrial Fibrilation
- Associate Professor Alex McLellan's explanation of AF
- How to check your pulse
Useful links
- Key Opinion Leader Series: Atrial Fibrillation: What Women Need to Know Interview with Dr. Karen Phillips
- Living With Atrial Fibrillation – Sally Brooks’ Story
- Addressing the Gender Disparity in the Treatment and Management of Atrial Fibrillation in the Asia-Pacific Region
- AF information from the Stroke Foundation
- Heart Support Australia is a NFP aimed at providing support and resources for people after a cardiac event
- Heart Rhythm Alliance
- Atrial Fibrillation Support Forum