1 Introduction
Evidence suggests that “atrial fibrillation (AF) begets AF,” meaning that AF promotes left atrial (LA) remodeling electrophysiologically and structurally, and vice versa.1 Use of a mapping system that allows electrophysiological and anatomical information to be combined has shown that LA remodeling can ultimately manifest as low-voltage zones (LVZs).2 Previously reported studies have shown existence of LVZs in the LA to be a strong predictor of AF recurrence after pulmonary vein isolation (PVI),3 and LVZ ablation added to PVI has been shown to improve ablation outcomes.4 LVZs are commonly seen on the anterior LA wall in patients with AF,5-7 but pathophysiologic factors responsible for development of such LVZs have not been fully elucidated. Mechanical compression of the LA by extracardiac structures such as the vertebrae and descending aorta has been associated with development of LVZs on the posterior LA wall.5 On the basis of this reported association, we hypothesized that mechanical compression by an anatomically deviated or expanded ascending aorta is, at least in part, responsible for development of LVZs on the anterior wall of the LA. We conducted a retrospective study in which we evaluated the relation between anatomical features of the ascending aorta and sinus of Valsalva and distribution of LVZs on the anterior LA wall in patients with AF.