“Cardioneuroablation” – new treatment for neurocardiogenic syncope, functional AV block and sinus dysfunction using catheter RF-ablation

Abstract

Cardiac neuroablation is a new technique for management of patients with dominantly adverse parasympathetic autonomic influence. The technique is based on radiofrequency (RF) ablation of autonomic connections in the three main ganglia around the heart. Their connections are identified by Fast-Fourier Transforms (FFTs) of endocardial signals: sites of autonomic nervous connections show fractionated signals with FFTs shifted to the right. In contrast, normal myocardium without these connections does not show these features. RF-ablation is thought to inflict permanent damage on the parasympathetic autonomic influence because its cells are adjacent to the heart whereas sympathetic cells are remote. Twenty-one patients with a mean age of 48 years, neurally mediated reflex syncope in six, functional high grade atrioventricular block in seven and sinus node dysfunction in 13 (there is overlap between the second and third groups) were treated. Follow-up for a mean of 9.2 months demonstrated success in all cases with relief of symptoms. No complications occurred.

Targets and End Points in Cardiac Autonomic Denervation Procedures

“…Endocardial GP ablation has been increasingly used to treat severe vagal-related arrhythmias. [8][9][10][11][12][13][14] Although the guidelines 20 indicate pacemaker implantation for cases of symptomatic bradycardia and atrioventricular block, the fact that these patients are mostly young and otherwise healthy individuals encourages a more conservative approach.…”

“…The diverse GP-mapping strategies used by different authors (1, high-frequency endocardial stimulation [2][3][4][5][6][8][9][10][11][12] ; 2, purely anatomic location 7,13 ; and 3, atrial electrogram characteristics 1,10,14,15 ) emerged as potential alternatives, with each one proposing specific end points (1, evoked reflex abolition; 2, ablation of all anatomic GP sites achieved; and 3, elimination of all fragmented potentials, respectively). However, some important questions still remain whichever technique is chosen:…”

“…Ganglionated plexus (GP) ablation for the treatment of vagal-related atrial fibrillation [1][2][3][4][5][6][7] and symptomatic bradycardia, [8][9][10][11][12][13][14] such as cardioinhibitory vasovagal syncope, has been widely studied, and although convincing results had been reported by some authors, no consensus still exists on the most adequate technique to identify the critical targets or end points indicating clinical vagal attenuation.…”

Teste de inclinação (Tilt-test): do necessário ao imprescindível

“…Even though the European guidelines on syncope do not recommend the HUTT for patients that have a typical clinical history of VVS, the tilt test is valuable in identifying the type of VVS (cardioinhibitory, vasodepressor or mixed). Some authors recommend different treatment options depending on the type of vasovagal syncope, so in this case, HUTT would serve as therapeutic guidance 5,8 . Pachon et al 8 recently published a new therapeutic alternative for patients with neurocardiogenic syncope, which would be more suitable for patients with cardioinhibitory VVS.…”

Pulmonary Vein Isolation for Atrial Fibrillation in Patients With Paroxysmal Atrial Fibrillation and Prolonged Sinus Pause

“…[11][12][13] Pachon, et al reported recently that persistent parasympathetic denervation and sympathetic reinnervation after endocardial radiofrequency ablation of autonomic connections in the 3 main ganglia were demonstrated by the permanent modification of the heart rate variability in the chronic phase, leading to amelioration of sinus node function. 14) Recent reports have also shown improved sinus node function after PV isolation. 15,16) Thus, both reverse remodeling of sinus node function and parasympathetic denervation might reduce the recurrence of AF.…”