The Role of the Autonomic Nervous System as Both “Trigger and “Substrate” in Atrial Fibrillation

KEYWORDS Atrial fibrillation Autonomic nervous system Efferent autonomic nerves Afferent autonomic nerves Baroreceptors Atrial remodeling Autonomic remodelingKEY POINTS There are several interacting mechanisms that serve either as (1) trigger or (2) substrate (maintain)atrial fibrillation (AF). Efferent autonomic activity is well-known to trigger AF, even in structurally normal hearts. AF is associated with autonomic atrial neural remodeling (sympathetic and parasympathetic hyperinnervation as well as nerve growth). However, efferent autonomic tone does not seem to influenceAF progression. There is emerging evidence of afferent or regulatory autonomic nervous system dysfunction in patients with AF. Reversible dysfunction of volume-regulating reflexes occurs during AF with persisting abnormalities during sinus rhythm. These studies could provide a mechanistic link for the progression of AF