Vagal denervation in atrial fibrillation ablation: A comprehensive review

Abstract

Although pulmonary vein isolation is accepted as an established interventional treatment in paroxysmal atrial fibrillation (AF), alternative modalities are being investigated because of the high recurrence rates of nonparoxysmal forms. One of the alternative ablation approaches is ablation or modification of vagal ganglionated plexi (VGP). The technique has not only been used in vagally mediated AF but also investigated in paroxysmal and nonparoxysmal AF. Clinical studies demonstrate significant discrepancy related with detection of VGP sites or ablation targets and definition of procedurel end-points, so far. In this review, we aimed to discuss the current data on the role of VGP in the pathogenesis of AF and potential therapeutic implications of ablation of these ganglia.

Figure 1

Schematic view of vagal ganglionated plexi. Pachon et al. (Ref. 51) re-named three fat pads in their study. According to this naming, ganglion A, B, and C correspond to superior vena cava-aorta fat pad, right pulmonary vein fat pad, and inferior vena cava-left atrium fat pad, respectively. Please pay attention similar anatomical localization of superior vena cava-aorta fat pad and superior right atrial vagal ganglionated plexus, right pulmonary vein fat pad and posterior right atrial vagal ganglionated plexus, and inferior vena cava-left atrium fat pad and posteromedial left atrial vagal ganglionated plexus CS - coronary sinus; GA - ganglion A; GB - ganglion B; GC - anglion C; LA - left atrium; LAA - left atrial appendage; LIPV - left inferior pulmonary vein; LSPV - left superior pulmonary vein; PMLA, VGP - posteromedial left atrial vagal ganglionated plexus; PLLA - posterolateral left atrial; PRA VGP - posterior right atrial vagal ganglionated plexus; RA - right atrium; RIPV - right inferior pulmonary vein; RSPV - right superior pulmonary vein; SLA - superior left atrial vagal ganglionated plexus; SRA VGP - superior right atrial vagal ganglionated plexus; VCI - vena cava inferior; VCS - vena cava superior

Figure 2

Spectral mapping and intracardiac recordings of fibrillar and compact atrial myocardium. (a) The fibrillar atrial myocardium presents a fractionated pattern with frequency >100 Hz on spectral analysis. (b) The compact atrial myocardium demonstrates homogenous spectrum with frequency <40 Hz on spectral analysis. (c) Areas that are compatible with fibrillar atrial myocardium demonstrates a complex fractionated pattern with ≥4 deflections at filter settings of 300–500 Hz on intracardiac recordings. (d) Areas that are compatible with compact atrial myocardium demonstrates monophasic or biphasic pattern on intracardiac recordings