Pulmonary veins in the substrate for atrial fibrillation

Atrial fibrillation (AF) is classically proposed to result from multiple wandering atrial wavelets [(1,2)][1]. However, recent experiments by Jalife et al. [(3)][2]have implicated an additional role for single micro–re-entrant circuits within the left atrium in AF. The pulmonary veins (PVs) are