Italian Cardioneuroablation Study for Neurocardiogenic Syncope Patients (ItalianCNA)

Efficacy of Transcatheter Ablation of Ganglionic Plexuses (Cardioneuroablation) in Right Atrium in Patients With Asystolic Neuromediated Syncope

Multicenter Italian interventional "proof of efficacy" clinical trial that aims to evaluate the incidence of asystolic pauses and heart rate in patients with CNS who performed severe CNA identified through asystolic pauses identification by implantable loop recorder. The study is independent, "investigator-initiated," sponsored by a nonprofit scientific association called the Italian Multidisciplinary Group for the Study of Syncope (GIMSI).

The so called "Cardioneuroablation (CNA)" focused on the endocardial ablation of atrial ganglionated plexi has proven to be efficacy in patients affected by neuro-mediated cardioinhibitory syncope (NCS). No center currently has sufficient case series to establish long-term efficacy and safety results, for which a multicenter interventional study is therefore needed. The aim of the study will be to evaluate the efficacy and safety of CNA focused in NCS patients. The ablation procedure, consists of radiofrequency delivering at right atrial anatomic sites where the underlying presence of GP clusters is regarded as highly probable: 1) the inferior-posterior area (first ablation site): inferior right GP placed between inferior vena cava, coronary sinus ostium and near the atrio-ventricular groove, 2) the superior-posterior area (second ablation site): superior right atrial GP, adjacent to the junction of the superior vena cava and the posterior surface of RA.

The ablative procedure involves applying radiofrequency deliveries in the two Right atrium anatomical sites close to the two main ganglionic plexuses of the right atrium: Inferior-posterior area (site of first ablation) corresponding to the right inferior atrial ganglion located between the inferior vena cava, coronary sinus ostium and near the atrioventricular node Upper-posterior area (site of second ablation) corresponding to the right superior atrial ganglion located between the superior vena cava and the posterior surface of the right atrium

Comparison of mean heart rate, before and after cardioneuroablation, incidence of (pre)syncopal episodes before and after CNA and, finally, beat-to beat HR variability during ILR monitoring

intrapatient comparison of mean heart rate (bpm), beat-to-beat variability of heart rate, before and after CNA.

Inclusion Criteria: Age between 18 and 60 years Patients with a clinical diagnosis of neuromediated syncope according to class I criteria of the ESC guidelines, Table 1 Clinical history of recurrent syncope (≥2 in the last year or ≥3 in the last 2 years), severe, not tolerated by the patient Documentation of ≥2 asystolic pauses >3 sec daytime on ECG monitoring by implantable loop recorder (ILR), with or without syncope Refusal by patient to perform pacemaker implantation Tilt test is recommended but not mandatory. Patients with negative tilt test are also enrollable. It can be either positive or negative. Exclusion Criteria: Absence of sinus dysfunction and atrioventricular node disease. Absence of structural heart disease Possible alternative diagnoses of syncope

The study envisages the subsequent activation of other participating centres to recruit and enrol patients to undergo the Cardioneuroablation procedure

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