The autonomic nervous system and arrhythmias

Abstract

The autonomic nervous system is involved in the trigger of arrhythmias that are due to an arrhythmogenic substrate and in the maintenance of these arrhythmias. Pulmonary vein isolation (PVI) is the main therapeutic strategy for paroxysmal atrial fibrillation. The intrinsic autonomic nervous system located around the heart (which is also known as the ‘ganglionated plexi [GP]’) is suspected to be related to both the onset and maintenance of atrial fibrillation. The vagal response can be provoked by frequent stimulation of the GP, and GP ablation has been reported to be effective for suppressing paroxysmal atrial fibrillation. It is thus possible that PVI could become a therapeutic strategy for both tachyarrhythmia (i.e., atrial fibrillation) and bradyarrhythmia (i.e., sick sinus syndrome). According to studies of catheter ablation for paroxysmal atrial fibrillation that is associated with sick sinus syndrome, in some patients the presence of sinus node dysfunction is accompanied by a higher recurrence of atrial fibrillation and will require the implantation of a pacemaker for sinus node dysfunction. It was also suggested that the GP may be involved in the development of atrial fibrillation. However, our knowledge about selective autonomic modification and therapeutic endpoints is limited. As a therapeutic strategy for both tachyarrhythmia and bradyarrhythmia, neuromodulation therapy has shown promise but remains controversial. Further investigations of the long-term effects of neuromodulation therapy for arrhythmias are necessary.