The MagnaSafe Registry: Determining the Risks of MRI in the Presence of Pacemakers and Implantable Cardioverter Defibrillators

The MagnaSafe Registry is an investigator initiated study designed to determine the risks of performing MRI for patients with pacemakers and Implantable Cardioverter-Defibrillators (ICDs). We hope that the results of the registry will provide physicians the risk-assessment data needed to assess the use of MRI as a diagnostic tool when no alternative diagnostic imaging technology is appropriate.

The number of patients living with permanent pacemakers or ICD devices in the United States is increasing dramatically as a result of expanded indications. Between 1990 and 2005, an estimated 2.8 million pacemakers and 690,000 ICDs were implanted in the United States. The number of implanted devices continues to increase without an apparent plateau.

Magnetic resonance is the imaging modality of choice for the diagnosis of many diseases of the brain, spinal cord, and musculoskeletal system. For some disease states, no acceptable alternative diagnostic imaging method is available. As the number of implanted cardiac devices is increasing, the clinical indications for MRI are expanding as well. Marketing research estimates that approximately 27.5 million MRI procedures were completed in 2007 (The Medical Information Division of IMV, LTD). It is predicted that there is a 50-75% probability that a patient with a pacemaker or ICD will have the need for an MRI over the lifetime of the device.

Most physicians consider the presence of a pacemaker or ICD to be an absolute contraindication to an MRI study. Patients are denied the examination, even when MR is clearly the superior diagnostic modality or when there is no acceptable alternative imaging test available. To provide optimal care to the increasing number of patients with an implanted cardiac device, health care professionals must have the capability to perform MR imaging with minimal risk and full knowledge of the possible complications.

The present study will create a registry of patients with pacemakers and ICDs who will undergo clinically indicated MRI and will document any adverse event or change in device parameters that may be associated with the imaging procedure. The results of this registry will provide the medical community with an accurate documentation of risk to patients and will establish a protocol of patient screening and device reprogramming for the purpose of maximizing the safe performance of MRI as a diagnostic tool in patients with implantable cardiac devices when indicated.