Experiences of magnetic resonance imaging scanning in patients with pacemakers or implantable cardioverter-defibrillators

Background/Aims: Despite the U.S. Food and Drug Adminstration approving a magnetic resonance imaging (MRI)-conditional pacemaker system in 2011, many physicians remain reluctant to perform MRI scanning in patients with cardiac implantable electronic devices. Herein, we aimed to evaluate the real-world safety of MRI in these patients. Methods: This single-center retrospective study examined the interrogation data and outcomes of patients with pacemakers or implantable cardioverter defibrillators who underwent MRI. MRI interrogation data were collected pre- and post-MRI and after 1 month of follow-up; these included the lead impedance, measured P- and R-wave amplitudes, and capture threshold. We compared these results between the magnetic resonance (MR)-conditional and conventional groups. Results: From September 2013 to December 2015, 35 patients with cardiac implantable electronic devices underwent 43 MRI scans, with a mean follow-up of 5 months. Among these 35 patients, 14 (40%) had MR-conditional devices and 21 (60%) had conventional devices. Seven patients had high voltage devices, which were all the conventional type. There were no adverse events associated with MRI during the follow-up period, and there were no significant differences in the interrogation data changes between the conventional and MR-conditional groups. Conclusions: This single-center retrospective study found that MRI can be performed safely in patients with pacemakers or implantable cardioverter defibrillators, regardless of the MRI support, as long as appropriate precautions are taken.