Atrial fibrillation (AF), the most common clinically relevant
arrhythmia, affects 2.2 million individuals in the USA and 4.5 million in Europe, resulting in significant morbidity and mortality.
Pharmacotherapy aimed at controlling both heart rate and rhythm is employed to relieve AF symptoms, though debate continues about which approach is preferable. AF prevalence rises with age from 0.4% to 1% in the general population to 11% in those aged >70 years. AF is associated with a pro-thrombotic state and other comorbidities; age,
hypertension,
heart failure and
diabetes mellitus all play a key role in AF pathogenesis. Anti-coagulation is essential for
stroke prevention in patients with AF and is recommended for patients with one or more risk factors for
stroke. Used within the recommended therapeutic range,
warfarin and other
vitamin K antagonists decrease the incidence of
stroke and mortality in AF patients.
Warfarin remains under-used, however, because of the perceived high risk of haemorrhage, narrow therapeutic window and need for regular monitoring. Several novel anti-
coagulants show promise in AF-related
stroke prevention. In particular, the novel, oral,
direct thrombin inhibitor,
dabigatran etexilate, recently licensed by the US Food and Drug Administration (FDA) and Health Canada has shown improved efficacy and safety compared with
warfarin for
stroke prevention in AF, and has the potential to replace
warfarin in this indication. The increasing number of new therapeutic options, including improved
anti-arrhythmic agents, novel anti-
coagulants and more accessible
ablation techniques, are likely to deliver better care for AF patients in the near future.