BIO|MASTER.CorSky Family Post-market Study for the CorSky Family of ICDs

Inclusion Criteria: * Standard indication for ICD or CRT-D therapy according to clinical guidelines * Planned for de novo implantation of an ICD/CRT-D, or upgrade/exchange from existing ICD/CRT-D or pacemaker * Ability to understand the nature of the study. * Ability and willingness to perform all on-site follow-up visits at the study site. * Ability and willingness to use the CardioMessenger and acceptance of the BIOTRONIK Home Monitoring® concept. Exclusion Criteria: * For VR-T DX and CRT-DX: Permanent atrial tachyarrhythmia * For VR-T DX and CRT-DX: Patients requiring atrial pacing * Planned for His-Bundle-Pacing * Planned cardiac surgical procedures or interventional measures other than the study procedure within the next 12 months * Pregnant or breast feeding. * Age less than 18 years. * Participation in an interventional clinical investigation in parallel to this study. , * Life-expectancy less than 12 months.