The clinical and electrophysiological implications of asymptomatic atrial fibrillation.

Atrial fibrillation (AF) is the commonest arrhythmia encountered in clinical practice and is frequently associated with significant symptoms. Asymptomatic AF may also increase the risks of heart failure, thromboembolism and cardiomyopathy but its prevalence is significantly underestimated by routine surveillance methods. The development of long-term external monitors and implantable devices has offered a new insight into the true prevalence of asymptomatic AF. Similar management strategies should be applied to both symptomatic and asymptomatic patient groups and anticoagulation should be continued indefinitely in those with a history of AF and risk factors for thromboembolism. Enhanced detection of clinically silent AF could improve outcomes but the resource implications will be significant.