From bench to bedside: The clinical relevance of atrial electrical remodeling in atrial fibrillation therapy

Abstract

Atrial electrical remodeling spans molecular, electrical, and structural alterations that shorten refractoriness, facilitate reentry, and ultimately create the atrial substrate underlying atrial fibrillation (AF). These changes include ion channel dysfunction, calcium-handling abnormalities, oxidative injury, and deranged proteostasis that are tightly intertwined with atrial fibrosis and cardiomyopathy. High-density mapping and advanced imaging now allow in vivo staging of this substrate: left atrial low-voltage areas and functional conduction phenomena identify regions of fibrosis and conduction slowing that are associated with postablation recurrence, although the benefit of low-voltage area-targeted substrate ablation remains uncertain. Building on this pathophysiological framework, this review integrates experimental and clinical evidence to guide decision making in AF therapy, emphasizing early rhythm-control strategies and careful substrate characterization in sinus rhythm. Pulmonary vein (PV) isolation is presented as the cornerstone of ablation, whereas adjunctive substrate-oriented strategies, including low-voltage modification, hybrid surgical-catheter approaches, and vein of Marshall-based techniques, are discussed as investigational options for selected high-risk patients. Finally, the review contrasts PV- and non-PV-dependent forms of AF and appraises emerging artificial intelligence-guided electrogram interpretation within a mechanism-driven framework for personalized management of atrial electrical remodeling.

Keywords: Electrical remodeling; Paroxysmal and persistent atrial fibrillation; Pivot sites; Sinus rhythm; Slow conduction.