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.