Catheter Ablation of Right Atrial Ganglionated Plexi in Patients With Vagal Paroxysmal Atrial Fibrillation

Abstract

Background— Catheter ablation of ganglionated plexi (GP) in the left atrium has been proposed in different subgroup of patients with atrial fibrillation (AF). Anatomic studies found a high prevalence of GP in the posterior surface of the right atrium (RA). Experimental data suggested the potential role of right atrial GP in the AF initiation and maintenance. The aim of our study was to assess the efficacy of GP ablation in RA in patients with vagal AF. Methods and Results— Thirty-four patients without structural heart diseases were randomly assigned for a selective ablation procedure targeted on the elimination of vagal reflex evoked by high frequency stimulation or an extensive approach at anatomic sites of GP. All patients underwent Holter ECG and heart rate variability evaluation at baseline and at 3, 6, 12, and 18 months of follow-up. At a mean follow-up of 19.7±5.2 months, AF recurred in 5 of 17 patients with anatomic ablation and in 13 of 17 patients with a selective approach ( P =0.01). No patient had major complications. After ablation, heart rate variability parameters showed a significant parasympathetic (and sympathetic) denervation in the first 6 months, which was more prominent in patients with anatomic GP ablation and in those without AF recurrence. Conclusions— This study demonstrates that in a selected population of vagal paroxysmal AF, the anatomic ablation of GPs in the RA is effective in about 70% of patients. These results confirm that atrial vagal denervation can abolish AF, as suggested by experimental and clinical data.

Long-Term Effects of Ganglionated Plexi Ablation on Electrophysiological Characteristics and Neuron Remodeling in Target Atrial Tissues in a Canine Model

“…9,14 However, an animal study 27 reported ablation of the right pulmonary vein-atrial junction fat pads facilitated rather than prevented the initiation of AF. Another clinical study assessed the long-term outcome of patients who underwent anatomic GP ablation for paroxysmal AF, 29 results demonstrated that anatomic GP ablation could only achieve short-term suppression of AF inducibility; however, this result was not maintained over the long-term.…”

“…For example, Oh et al 12 reported that radiofrequency ablation of fat pads may not achieve long-term suppression of AF induction in a canine model. By contrast, Pokushalov et al 13 and Calo et al 14 confirmed that GP ablation in humans could be an efficient treatment for AF.…”

Pharmacological Tests in Atrial Fibrillation Ablation

“…34 It has been suggested that ganglionated plexi may have a role in the initiation and maintenance of both paroxysmal and non-paroxysmal AF. [35][36][37][38][39][40][41] Localisation is usually performed on the endocardium either anatomically, by vagal response following high-frequency stimulation, or by Fourier transform in sinus rhythm. 35,37 Although ganglionated plexi ablation significantly reduces AF recurrence, the long-term success rate is lower than after PVI.…”

“…[35][36][37][38][39][40][41] Localisation is usually performed on the endocardium either anatomically, by vagal response following high-frequency stimulation, or by Fourier transform in sinus rhythm. 35,37 Although ganglionated plexi ablation significantly reduces AF recurrence, the long-term success rate is lower than after PVI. [35][36][37][38][39][40][41] Interestingly, in addition to PVI, the suppression of ganglionated plexi response -particularly that observed during cryoablation -may reduce AF recurrence.…”

“…35,37 Although ganglionated plexi ablation significantly reduces AF recurrence, the long-term success rate is lower than after PVI. [35][36][37][38][39][40][41] Interestingly, in addition to PVI, the suppression of ganglionated plexi response -particularly that observed during cryoablation -may reduce AF recurrence. 40,41 Although many authors believe that additional ablations are required for non-paroxysmal AF or some paroxysmal AF, no randomised studies have consistently shown which strategy to use.…”