title: Atrial fibrillation.
abstract: Essential facts Atrial fibrillation (AF) causes an abnormal, sometimes fast pulse, and is the most common heart rhythm disturbance. It occurs when electrical impulses controlling the heart's natural rhythm lose co-ordination. People with AF have a four or five times higher risk of stroke because it increases the risk of a blood clot forming in the chambers of the heart. The condition is responsible for 22,500 strokes a year in the UK, according to the British Heart Foundation (BHF).
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D006801:Humans; D012307:Risk Factors; D006113:United Kingdom