Clinical Study to Confirm MRI Safety and Effectiveness Using St. Jude Medical (SJM) Cardiac Rhythm Management Systems

Inclusion Criteria: * Are implanted with one of the following SJM device/lead combinations evaluated in this study for at least 60 days (can include patients with an eligible SJM lead for ≥ 60 days OR patients with a new eligible SJM pacemaker, Implantable Cardioverter-Defibrillators (ICD), or Cardiac Resynchronization Therapy Defibrillators (CRT-D) device and eligible SJM lead implanted for at least 60 days: 1. Accent MRI™, Assurity MRI™, Endurity MRI™, or Endurity pacemaker with Tendril™ STS Model 2088 lead 2. Accent MRI™, Assurity MRI™, Endurity MRI™, or Endurity pacemaker with IsoFlex™ Optim (Model 1944 or 1948) lead 3. Ellipse™ VR/DR or Fortify Assura VR/DR ICD with Tendril™ STS (Model 2088) or Tendril MRI™ and Durata™ or Optisure™ leads 4. Quadra Assura™ CRT-D with Tendril™ STS (Model 2088), Durata™ or Optisure™, and Quartet™ Quadripolar leads * Are implanted with an eligible SJM pacemaker, ICD, or CRT-D device 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 subject can communicate with site personnel during the MRI scan * Be able to provide informed consent for study participation (legal guardian is NOT acceptable) * Be willing and able to comply with the prescribed follow-up tests and schedule of evaluations Exclusion Criteria: * 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 other non-MRI compatible device or material implanted * NOTE: MRI compatible knee replacements, hip replacements, stents, etc. may be included as long as the labeling of these devices allow MRI scans conducted per this protocol * NOTE: MRI compatible mechanical, prosthetic, and bioprosthetic heart valves may be included as long as the labeling of these devices allow for MRI scans conducted per this protocol * NOTE: Non-removable dental implants may be included * Have a lead extender, adaptor, or capped/abandoned lead * Be unable to fit in MRI bore, i.e., subject will come into contact with the magnet façade inside the MRI bore. * Are currently participating in a clinical investigation that includes an active treatment arm * Are pregnant or planning to become pregnant during the duration of the study * Have a life expectancy of less than 3 months due to any condition * Meet exclusion criteria per local law (e.g. age)