This study assesses the value of arrhythmogenic substrate identification and elimination by catheter ablation to prevent recurrent ventricular arrhythmias and sudden cardiac death in a series of selected patients with primary cardiomyopathy and/or channellopaties with ICD implantation.

The present study is designed as a prospective single center study. All selected patients with implanted ICD to prevent VT/VF recurrence who are referred to the Arrhythmology Department of San Donato Milanese Hospital, for the management of a primary cardiomyopathy fulfilling the inclusion criteria will be enrolled. Primary cardiomyopathies include: - dilated cardiomyopathy (DCM), - arrhythmogenic right ventricular cardiomyopathy (ARVC), - left ventricular non-compaction (LVNC), - early repolarization syndrome (ER), and - hypertrophic cardiomyopathy (HCM).Channellopaties incude - Long QT syndrome and J-wave syndrome) Patients with or without a family history of BrS, will also be included. Endo-epicardial electroanatomical 3Dmapping and RFA ablation will be systematically performed according to a standardized procedure. Patients will be monitored for at least 3 days after RF ablation. Before hospital discharge, echocardiography and 12-lead ECG will be performed. Patients will be followed-up clinically after the procedure as per normal clinical practice. Follow-up visits will be systematically scheduled at 3, 6, 12, 18 and 24 months. 12-lead ECG and ICD interrogation will be performed at each follow-up visit. Patients will be instructed to immediately contact the center in case of symptoms suggestive of ventricular arrhythmias. Documentation for intercurrent events will be requested and collected. The maximal duration of study participation for the individual patients is two years.

Inclusion Criteria:

• Patients affected by cardiomyopathies and/or channellopaties (long QT syndrome and J-wave syndrome) with and without documented family history of BrS;
• Presence of symptoms attributable to VA and/or presenting documented arrhythmic episodes;
• Patients with an ICD already implanted;
• Patients referred to the centre for an electrophysiological study and indication for a potential concomitant radio-frequency catheter ablation (RFA) of ventricular tachycardia (VT) or ventricular fibrillation (VF);
• Age ≥ 18;
• Willingness to attend follow-up examinations;
• Written informed consent for the participation in the trial

Exclusion Criteria:

• Pregnancy or breast-feeding;
• Life expectancy < 12 months