Atrial fibrillation is the most common cardiac arrhythmia in everyday clinical practice, and has a significant morbidity and mortality related to it, either directly or indirectly. Atrial fibrillation results in a heavy burden on NHS services, in terms of both in-patient admissions, and out-patient care. Atrial fibrillation can be symptomatic or asymptomatic, yet morbidity and mortality are not much different in relation to symptom status. However, young patients with ‘lone AF’(i.e. AF without ‘overt’ structural heart disease, as defined by essentially normal clinical history and examination, electrocardiogram, chest X-ray, and, in more recent series, the ECG) are often considered as being ‘at low risk’, although recent
data have been less conclusive on this aspect