Atrial fibrillation

First signs and symptoms of atrial fibrillation

Atrial fibrillation (AF) is a heart condition in which the heart rate is irregular and the pulse rate is faster than normal. People may experience symptoms such as palpitations (a noticeably rapid, strong or irregular heart beat), dizziness, breathlessness and tiredness. Sometimes people have no symptoms at all. We asked Dr Tim Holt, an academic GP, to explain what atrial fibrillation (AF) is, and to describe its symptoms.
In our interviews people talked about the way they first experienced AF. For some, the first episode of AF occurred ‘out of the blue’ while they were going about normal everyday activities. Some needed to urinate frequently, others had a dizzy spell at work or experienced symptoms such as palpitations while sitting quietly watching television. Eileen explained how she woke up one morning and discovered she ‘couldn’t stand up long enough to cook breakfast’. George X collapsed in town. David X had an ‘out of body’ experience and ‘strange floating sensations’ while driving.
For others, the onset of AF was associated with physical activities. Keith first had palpitations while playing cricket, Janet found herself ‘getting very, very breathless’ while walking uphill on holiday, and Ginny experienced a ‘pounding heart and a very, very fast pulse’ while mountain climbing which left her legs ‘a bit sort of weak’.
Some people saw their GP after becoming aware of a high heart rate while exercising. Paul wore a personal heart rate monitor at the gym, and thought it must be broken. When he borrowed another and his heart rate was still high, he saw his GP. Raymond noticed a high pulse rate while working out and feared he was going to have a heart attack.
In some cases people may be unaware of symptoms of AF (asymptomatic). They are diagnosed by chance when they consult their doctor about other health concerns. (For more see ‘Diagnosing atrial fibrillation’ and ‘What having atrial fibrillation feels like’).


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