A Clinical Evaluation of the Durata or Optisure High Voltage Leads and Ellipse VR ICD Undergoing MRI, an IDE Study

Inclusion Criteria: * Are implanted with the Durata or Optisure lead for at least 60 days (can include patients with Durata or Optisure lead for \> 60 days OR patients with a new Ellipse VR ICD and/or Durata/Optisure lead implanted for at least 60 days * Are implanted with an Ellipse VR ICD pectorally * Be willing to undergo an elective MRI scan without sedation NOTE: Antianxiety agents (e.g. minor tranquilizers, etc.) may be used as long as the patient can communicate with site personnel during the MRI scan * Capture threshold is stable \< 2.5V @ 0.5ms * Ventricular sensing is measurable (patient has underlying rhythm \> 30bpm) and the sensing amplitude is \> 4mV * Be able to provide informed consent for study participation (legal guardian or legally authorized representative is NOT acceptable) * Be willing and able to comply with the prescribed follow-up tests and procedures * Are not contraindicated for an MRI scan (per the MRI Screening Form) Exclusion Criteria: * Have a competitor's MRI compatible endocardial lead implanted or capped * Have another existing active implanted medical device, e.g., neurostimulator, infusion pump, etc., that has MR labeling that will not allow the MRI scans per this protocol to be completed. * Have a lead revision of the Durata/Optisure lead occur \< 60 days of the baseline visit * Have other non-MRI compatible device or material implanted NOTE: MRI compatible knee replacements, hip replacements, stents, etc. may be included as long as th…