The Effects of Nuclear Magnetic Resonance Imagers on External and Implantable Pulse Generators

This study evaluates the effect of nuclear magnetic resonance (NMR) scanning on pacemaker function. it must be emphasized that each manufacturer's pulse generators and each pacing modality may behave differently and, therefore, require individual evaluation. According to our results, patients with pacemakers should have their pacing activity monitored continuously during scanning with the NMR 1500 gauss imaging system. External pulse generators should he net to the asynchronous mode and placed outside the NMR image volume but within the radiofrequency [RF] shield. Implanted pacemakers should be verified for type and mode of operation. Ail implantable pulse generators evaluated reverted from the demand to the asynchronous mode within the magnetic field of the scanner. There was no observable damage to the discrete pacemaker components that were tested.