Anticoagulation in atrial fibrillation

### Learning objectives One in three of us will be diagnosed with atrial fibrillation (AF) at some point in our lives.1 Over 1.2 million individuals in the UK have been diagnosed with AF, and thousands still remain undiagnosed.2 3 Due to the ageing population, the number of individuals with AF in Europe will double in the next 50 years,3 contrasting with a fall in the incidence of myocardial infarction and stroke over recent decades.4 This shift in cardiovascular epidemiology is important as AF associates with a myriad of cardiovascular and non-cardiovascular complications (figure 1), and contributes to a 1.5-fold to 2.0-fold increase in all-cause mortality.5 Figure 1 Clinical events in the atrial fibrillation population. Cerebrovascular complications in red, other cardiovascular events in blue and other risks in green. Relative risk and 95% CIs are illustrated based on Odutayo et al. 5 The risk of ischaemic stroke in patients with AF is three to five times higher,6 with AF found in up to 30% of patients admitted with ischaemic stroke, and associated with a higher risk of fatal outcome.7 The risk of AF-related stroke can be mitigated through anticoagulation, with a 66% risk reduction with vitamin K antagonists (VKAs) and at least similar effectiveness with non-VKA.8 Stroke rates in patients with adequately anticoagulated AF are similar to those of patients without documented AF,9 with only 1 …