Inclusion Criteria:  Subject meets current clinical practice guidelines for implantation of ICD or CRT-D and will undergo one of the following:  de novo Medtronic CRT-D system implant de novo Medtronic ICD system implant (single or dual chamber) Subject has, per local law and requirements, the minimum age for autonomously signing an ICF Subject is willing to undergo implant defibrillation testing if requested. Subject is geographically stable and willing and able to complete the study procedures and visits for the duration of the follow-up.  Exclusion Criteria:  Subject is unwilling or unable to personally provide Informed Consent. Subject has contraindications for standard RV transvenous lead placement (e.g., mechanical right heart valve). Subject is contraindicated for ≤1 mg dexamethasone acetate. Subject has a life expectancy of less than 12 months  For subject undergoing defibrillation testing the following medical conditions exclude them:  Pre-existing or suspected pneumothorax during implant Current intracardiac left atrial or left ventricular (LV) thrombus Severe aortic stenosis Severe proximal three-vessel or left main coronary artery disease without revascularization Unstable angina Ejection Fraction less than 25% Recent stroke or transient ischemic attack (within the last 6 months) Known inadequate external defibrillation Any other known medical condition not listed that precludes their participation in the opinion of the investigator Subject is enrolled or planning to enroll in a concurrent clinical study that may confound the results of this study, without documented pre-approval from a Medtronic study manager. Subject with any exclusion criteria as required by local law (e.g., age or other). Pregnant women or breastfeeding women, or women of childbearing potential and who are not on a reliable form of birth regulation method or abstinence Subject with an existing pacemaker (including transcatheter pacing system), ICD, or CRT device or leads Subject with any evidence of active infection or undergoing treatment for an infection Recent (or planned) cardiac surgery or stenting less than 1 month before implant End stage renal disease Subjects with NYHA IV classification Subjects with a transplanted heart Subjects with previously extracted leads Subjects with Left Ventricular Assist Device