Atrial fibrillation (AF) is a heart condition that causes an irregular and often fast heartbeat. The top chambers of the heart (the atria) beat chaotically, so the heart does not pump as well. Around 1.5 million people in the UK have AF, and many more may have it without knowing.
Symptoms
- a fluttering, thumping or racing heartbeat (palpitations)
- an irregular pulse
- feeling breathless, tired or dizzy
- chest discomfort
Some people have no symptoms. AF can come and go (paroxysmal) or be there all the time (persistent or permanent).
Why AF matters
Because blood does not flow smoothly, clots can form in the heart. If a clot travels to the brain it can cause a stroke. AF also makes heart failure more likely.
What raises the risk?
- getting older
- high blood pressure, heart disease, heart valve problems or heart failure
- diabetes, obesity, sleep apnoea and an overactive thyroid
- drinking a lot of alcohol
Getting diagnosed
AF is diagnosed with an ECG, a test that records your heart's rhythm. If it comes and goes, you may wear a small monitor for a day or more. Some smart watches can pick up signs of AF, but you still need an ECG to confirm it.
Read about treatment for atrial fibrillation.
Common questions
Is atrial fibrillation dangerous?
AF itself is not usually life-threatening, but it makes a stroke up to 5 times more likely. That is why many people with AF are offered a blood thinner.
How do I check my pulse?
Place two fingers on the inside of your wrist, below your thumb. Count the beats for 30 seconds and double it. Notice whether the beat is regular or irregular.
Sources we used
- NHS, Atrial fibrillation
- NICE guideline NG196, Atrial fibrillation
- Arrhythmia Alliance and AF Association
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