The aim of this study was to assess safety and efficacy of SJM MRI conditional pacing system. The study hypothesized that cardiac MRI scan would not affect performance of SJM MRI conditional pacing system.

Accent Cardiac MRI study was a prospective, randomized ,multi-center study conducted in Asia. Subjects indicated for dual-chamber pacemaker and who signed study consent form were considered enrolled and post implant were randomized to either Cardiac MRI Scan Group or Control Group.

Clinical evaluation and device interrogation were performed at baseline, pre- and post-MRI scan, and one month post-MRI for all subjects. At 9-12 weeks post-implant, patients in Cardiac MRI Scan Group underwent an elective non-diagnostic cardiac MRI scan at 1.5 Tesla (T) while patients in Control group underwent device interrogation and clinical evaluation twice with a 45-minute waiting period in between. The safety endpoint was freedom from MRI-related complications while efficacy endpoint was change in right atrial/ ventricular (RA/RV) capture threshold and sensing amplitude from pre-MRI scan to one month post-MRI scan.

Inclusion Criteria

• Have an approved indication per American College of Cardiology(ACC)/ American Heart Association(AHA)/ Heart Rhythm Society(HRS)/ European Society of Cardiology(ESC) guidelines for implantation of a pacemaker
• Will receive a new dual chamber pacemaker and leads
• Be willing to undergo an elective MRI scan without complete sedation, that is ,under consciousness during MRI scan
• Be able to provide informed consent for study participation
• Be willing and able to comply with the prescribed follow-up tests and schedule of evaluations
• Is not contraindicated for an MRI scan (per the pre-MRI safety screening form)
• Age≥18 years
• Subjects must be able to undergo pectoral implantation

Exclusion Criteria

• Having an existing pacemaker or Implantable Cardioverter Defibrillator (ICD) .A new pacemaker and lead is required for enrollment
• Permanent Atrial Fibrillation/Flutter
• Are medically indicated for an MRI scan at the time of enrollment
• Have an existing active implanted medical device, e.g. neurostimulator, infusion pump etc
• Have a non-MRI compatible device or material implanted
• Have a lead extender or adaptor
• Be unable to fit in MRI bore; 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 allergic to dexamethasone sodium phosphate(DSP)
• Are pregnant or planning to become pregnant during the duration of the study
• Have a life expectancy of less than 12 months due to any condition
• Subjects with exclusion criteria required by local law (e.g. age)
• Are unable to comply with the follow up schedule

Death, Adverse Device Effect (ADE) and Serious Adverse Device Effect (SADE) from Baseline to 1 month post MRI Scan Visit were collected.

1. In the Serious Adverse Event Section, only SADE are reported.
2. In the Other (Not Including Serious) Adverse Events Section, only ADE are reported.
3. In the All-Cause Mortality Section, there are 4 deaths reported. All of them happened prior to cardiac MRI scan and were not related to study procedures.