AF is associated with considerable morbidity and mortality. The mortality rate of patients with AF is approximately double that of patients in normal sinus rhythm. The arrhythmia accounts for 10-15% of all ischaemic strokes, and 25% of ischaemic strokes in patients over 80 years of age. In 2001-2002, the prevalence of AF in Scotland was 8.7 per 1,000, increasing dramatically with age to 71 per 1000 in people aged over 85 years. The prevalence was higher among men. Currently there are an estimated 4.5m people in the European Union with paroxysmal or persistent AF, costing the EU around €13.5 billion per year.¹ This burden is likely to increase as the population ages.