Defibrillation Testing During Implantable Cardioverter Defibrillator (ICD) Replacement

This study will evaluate safety and clinical outcomes of a systematic defibrillation threshold testing in patient with indication for defibrillator replacement.

Inclusion Criteria: * Patients with an ICD (VR or DR) or CRT-D undergoing generator replacement. * Consent for participation * Affiliation to the French social security system Exclusion Criteria: * Atrial Fibrillation without effective anti-coagulation treatments. * Severe Aortic valve stenosis * Stroke occurred in the previous month * Hemodynamic instability contraindicating the high energy shock * Contraindication for anesthesia * Pregnant or breastfeeding women * Communication difficulties or neuropsychiatric disorder * Patients under protection of the adults (guardianship, curators or safeguard of justice)