Inclusion Criteria:

• Patient with ischemic or non-ischemic heart disease who meets current guidelines for ICD therapy and intends to undergo a de novo implant procedure for an EMBLEM™ S-ICD (or newer generation BSC S-ICD)
• Left ventricular ejection fraction ≤ 35%
• A passing EMBLEM™ S-ICD (or newer generation BSC S-ICD) screening ECG
• Patient ≥ 21 years of age willing and capable of giving informed consent
• Patient willing and capable of complying with follow-up visits

Exclusion Criteria:

• Patient with a history of spontaneous sustained VT or VF
• Patient with bradycardia pacing indication
• Patient eligible and scheduled for cardiac resynchronization implant
• Patient with a previous S-ICD or a previous transvenous pulse generator (pacemaker or defibrillator)
• Patient in NYHA Class IV documented in the medical records within 90 days before enrollment
• Patient with life expectancy shorter than 18 months due to any medical condition (e.g., cancer, uremia, liver failure, etc…)
• Patient receiving hemodialysis within 180 days before to enrollment
• Patients unable to give consent in person, including patients unable to read or write
• Patient who is known to be pregnant or plans to become pregnant over the course of the trial
• Patient unwilling or unable to cooperate with the protocol
• Participation in concurrent clinical study without prior approval from Boston Scientific
• Medical status (e.g., hemodynamic conditions ) of the patient doesn't allow programming devices with a conditional shock zone at 200 bpm and a shock zone at 250 bpm, in the judgment of the implanting physician and/or according to (inter) national guidelines