German Roentgen Society Statement on MR Imaging of Patients with Cardiac Pacemakers

The aim of this paper is to inform physicians, especially radiologists and cardiologists, about the technical and electrophysiological background of MR imaging of patients with implanted cardiac pacemakers (PM) and to provide dedicated clinical practice guidelines how to perform MR exams in this patient group. The presence of a conventional PM system is not any more considered an absolute contraindication for MR imaging. The prerequisites for MR imaging on pacemaker patients include the assessment of the individual risk/benefit ratio as well as to obtain full informed consent about the off label character of the procedure and all associated risks. Furthermore the use of special PM-related (e.g. re-programming of the PM) and MRI-related (e.g. limitation of whole body SAR to 2 W/kg) precautions is required and needs to be combined with adequate monitoring during MR imaging using continuous pulsoximetry. MR conditional PM devices are tested and approved for the use in the MR environment under certain conditions, including the field strength and gradient slew rate of the MR system, the maximum whole body SAR value and the presence of MR imaging exclusion zones. Safe MR imaging of patients with MR conditional PM requires the knowledge of the specific conditions of each PM system. If MR imaging within these specific conditions cannot be guaranteed in a given patient, the procedure guidelines for conventional PM should be used. The complexity of MR imaging of PM patients requires close cooperation of radiologists and cardiologists.

Conventional pacemaker systems are no longer an absolute but rather a relative contraindication for performing an MR examination. The procedural management of conventional pacemaker includes the assessment of the individual risk/benefit ratio, comprehensive patient informed consent about specific related risks and "off label" use, extensive PM- and MRI-related safety precautions as well as adequate monitoring techniques during the MR exam. Decisive for patient safety are precise understanding of, and compliance with, the terms of use for the specific MR-conditional pacemaker system. If the electrophysiological and MRI-specific conditions for use of MR-conditional pacemakers are not met or compliance with these conditions for use cannot be guaranteed, the device must be treated like a conventional pacemaker.