Patients who have permanent pacemakers or implantable cardioverter-defibrillators are often denied the opportunity to undergo MRI because of safety concerns.New research in the New England Journal of Medicine argues such safety concerns are incorrected and outdated.These concerns exist because of previous case reports in which appropriate protocols were not followed. Nazarian and a team of Penn researchers performed a prospective, nonrandomized study of 1,509 patients to assess the safety of MRI at a magnetic field strength of 1.5 Tesla. 58 percent had a pacemaker and 42 percent were fitted with an implantable cardioverter-defibrillator; no devices were considered “MRI-conditional.” In total, no long-term, clinically relevant adverse events were reported during the study. But in nine MRI exams a patient’s device reset to a backup mode—a finding that was transient in eight of the nine instances.

Precautions

1. Use 1.5-tesla magnet

2. Limit specific absorption rate to 1.5 W/kg for a maximum of 30 minutes

3. Informed consent

4. Stand by cardiologist and pacemaker technician