Left Atrial Wall Stress Distribution and Its Relationship to Electrophysiologic Remodeling in Persistent Atrial Fibrillation

Abstract

Background-Atrial stretch causes remodeling that predisposes to atrial fibrillation. We tested the hypothesis that peaks in left atrial (LA) wall stress are associated with focal remodeling. Methods and Results-Nineteen patients underwent LA mapping before catheter ablation for persistent atrial fibrillation.Finite Element Analysis was used to predict wall stress distribution based on LA geometry from CT. The relationship was assessed between wall stress and (1) electrogram voltage and (2) complex fractionated atrial electrograms (CFAE), using CFAE mean (the mean interval between deflections). Wall stress varied widely within atria and between subjects (median, 36 kPa; interquartile range, 26 -51 kP). Peaks in wall stress (Ն90th percentile) were common at the pulmonary vein (PV) ostia (93%), the appendage ridge (100%), the high posterior wall (84%), and the anterior wall and septal regions (42-84%). Electrogram voltage showed an inverse relationship across quartiles for wall stress (19% difference across quartiles, Pϭ0.016). There was no effect on CFAE mean across quartiles of wall stress. Receiver operating characteristic analysis showed high wall stress was associated with low voltage (ie, Ͻ0.5 mV) and electrical scar (ie, Ͻ0.05 mV; both PϽ0.0001) and with absence of CFAE (ie, CFAE mean Ͻ120 ms; PϽ0.0001). However, peaks in wall stress and CFAE were found at 88% of PV ostia. Conclusions-Peaks in wall stress were associated with areas of low voltage, suggestive of focal remodeling. Although peaks in wall stress were not associated with LA CFAE, the PV ostia may respond differently. (Circ Arrhythm Electrophysiol. 2012;5:351-360.)

The influence of the external structures in atrial fibrillation patients: Relationship to focal low voltage areas in the left atrium

“…The wall stress from the inside demonstrated by the shapes of the LA was reported by Hunter et al and is suggestive of focal remodeling [12].…”

“…Low voltage areas (LVAs) appear in the LA, which is the result of the progression of remodeling, and are suggested to be one of the important factors for the maintenance of AF by their development of slow conduction and wave collisions [4][5][6][9][10][11]. LA remodeling in AF patients is suggested to be associated with continuous stretch and wall stress from the inside, and LVAs are reported to increase in persistent AF (PsAF) patients compared to paroxysmal AF (PAF) patients [5,6,12]. However, as AF itself can promote atrial remodeling, it may just be the result of the continuous stress from AF.…”

Impact of asymmetrical dilatation of the left atrium on the long-term success after catheter ablation of atrial fibrillation

“…This could reflect the physical constraints (spine/sternum) [7], the changing tissue characteristics [8,9] and the increased anterior wall stress [10], which as shown undergo continuous expansion during AF progression.…”

Evaluation of geometric, functional and mechanical parameters of left atrium remodeling after surgical treatment of isolated atrial fibrillation

“…Немаловажными моментами являются на-блюдения о том, что механическая дисфункция предшествует расширению ЛП [13,14]. Что еще более важно, параметры механической функ-ции могут определять необходимость и сроки антикоагулянтной терапии [15].…”