AF is a supraventricular tachyarrhythmia characterized by uncoordinated atrial activation with consequent deterioration of atrial mechanical function. It is the most common arrhythmia in clinical practice, accounting for approximately onethird of hospitalizations for cardiac rhythm disturbances. It is classified, according to duration, as paroxysmal (intermittent, maximum duration of <7 days), persistent (< 1 year), and permanent AF (lasts for > 1 year and cardioversion either has not been attempted or has failed).