Safety of magnetic resonance scanning without monitoring of patients with pacemakers

Aims The objective of this study was to investigate whether it is safe to perform 1.5-Tesla magnetic resonance imaging (MRI) scans in pacemaker (PM) patients without pulse oximetry or electrocardiogram monitoring and with no special specific absorption rate (SAR) or time limits, provided that the PMs are interrogated and programmed to asynchronous mode prior to the scan. Methods and results This study reports the outcome of 207 MRI scans on PM patients at Rigshospitalet, Copenhagen University Hospital from June 2010 to September 2013. All MRIs were performed with the PMs in asynchronous mode and without additional monitoring. There were no adverse events registered among the PM patients during the study period. The only statistically significant change after MRI scans was a small, but clinically insignificant increase in atrial sense. No occurrences of reprogramming to power-on-reset were registered. Conclusion It is possible to perform MRI scans relatively safely in PM patients without additional monitoring or change in the normal MRI protocol, given that the PM has been assessed and reprogrammed prior to MRI. This is especially important to remember in the acute setting where MRI scans may be delayed when monitoring facilities are unavailable.