title: Advances in mechanisms of atrial fibrillation: structural remodeling, high-frequency fractionated electrograms, and reentrant AF drivers.
abstract: The mechanisms to explain atrial fibrillation (AF) have been widely debated. Although contemporary experimental techniques have provided more insight, hypotheses regarding AF propagation conceived in the early half of the century remain minimally altered and relevant today. Modern mapping technologies have implicated multiwavelet reentry as the electrophysiologic basis to explain AF propagation within the atrial myocardium; however, reentry has also been observed within pulmonary veins and may behave as a focal trigger. The ability to terminate AF by catheter ablation has provided additional clues to explain AF induction and sustenance. The presence of complex fractionated electrograms (CFAE) and subsequent successful CFAE-directed ablation suggest that diseased atrial myocardium is a necessary substrate for AF maintenance. Atrial remodeling creates differential areas of refractory periods and conduction velocity, which, in turn, creates a suitable environment for AF. This review addresses the complex relationship between remodeled atrial myocardium and reentry and explores the role of CFAEs in AF maintenance.
authors.affiliation: New England Cardiac Arrhythmia Center, Tufts-New England Medical Center, Tufts University School of Medicine, Boston, MA, USA.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Makati
authors.forename: Alawi A
authors.initials: AA
authors.lastname: Alsheikh-Ali
authors.forename: Ann C
authors.initials: AC
authors.lastname: Garlitski
authors.forename: Mark S
authors.initials: MS
authors.lastname: Link
authors.forename: Munther
authors.initials: M
authors.lastname: Homoud
authors.forename: Jonathan
authors.initials: J
authors.lastname: Weinstock
authors.forename: N A Mark
authors.initials: NA
authors.lastname: Estes Iii
mesh_terms: D001281:Atrial Fibrillation / Q000503:physiopathology* / Q000628:therapy; D018780:Body Surface Potential Mapping; D017115:Catheter Ablation / Q000379:methods*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods*; D006801:Humans; D054139:Tachycardia, Reciprocating / Q000601:surgery; D020257:Ventricular Remodeling