Evaluating MRI-compatible pacemakers: patient data now paves the way to widespread clinical application?

The worldwide use of both magnetic resonance imaging (MRI) and pacing devices has vastly increased in recent years and an important number of implanted patients likely will need an MRI over the course of the lifetime of their device. Although some studies have demonstrated that, given appropriate precautions, MRI can be safely performed in patients with selected implantable pacemakers, MRI in pacemaker patients is still contraindicated. Recently, new pacing systems have been specifically designed for safe use in the MRI environment and the first experience reported suggests that the technology is safe and may allow patients to undergo MRI. This review will describe the outstanding issues and controversies surrounding the safety of MRI imaging in pacemaker patients and the potential benefits of the new MRI-conditional technology. We will also discuss how to approach the decision whether or not an MRI-conditional system should be implanted and highlight key issues that warrant further studies.