This study aims to investigate the impact of antitachycardia pacing ( ATP) on the myocardial tissue with respect to its potential micro damage measured by several myocardial markers, especially by high-sensitive TroponinT.

Inclusion Criteria:

• All patients for de-novo implantation of a transvenous ICD (single chamber, dual chamber or cardiac resynchronization tehrapy) with left pectoral device position and planned apical location of the right ventricular defibrillation electrode.

Exclusion Criteria:

• Resuscitation, cardiac surgical procedure, acute coronary syndrome, acute myocardial infarction, coronary revascularisation, cardioversion or ablation during the past 4 weeks, if baseline high-sensitive Troponin T is elevated
• Known stenosis of coronary vessels with indication for coronary intervention or operative revascularisation
• Intracardiac thrombus or general contraindication against ventricular burst stimulation or intraoperative ICD-testing
• Atypical lead implantation with indication for defibrillation threshold testing by induction of ventricular fibrillation
• Right sided implantation of ICD
• Planned electrical cardioversion
• Lead explantation or -extraction during procedure
• Redo procedure (except of additional implantation of a right ventricular ICD lead)
• Present temporary pacemaker electrode
• ASA >= IV or NYHA IV
• Cardiogenic shock
• Pulmonary embolism, cerebrovascular insult or dialysis in the past 4 weeks
• Lack of consent of patient
• Minority of patient