Safe scanning, but frequent artifacts mimicking bradycardia and tachycardia during magnetic resonance imaging (MRI) in patients with an Implantable loop recorder (ILR)

Background: Patients with implantable devices are generally not permitted to undergo magnetic resonance imaging (MRI) because of potentially deleterious interactions. Little has been reported regarding the safety and effects of MRI scanning of patients with implantable loop recorders (ILRs). We evaluated the safety of scanning patients with ILRs and the output of the ILR after undergoing MRI. Methods:Ten patients underwent 11 MRI scanning events. All patients had Reveal Plus (Medtronic, Minneapolis, MN) ILRs. Seven cranial, two lumbar-spine, one shoulder, and one knee MRI were performed. All of the MRIs were performed with the understanding that the patient had an ILR. In each patient, the ILR was cleared moments before the scan and the integrity of the signal and time date stamp were verified. The devices were reinterrogated immediately after MRI in 10 patients and two days post MR scanning in one patient. Each patient was questioned post MRI regarding any symptoms experienced during the scan. Results: Both tachy and bradyarrhythmias appeared as artifacts as a result of ILR exposure to MR]. Post MR], none of the ILRs showed diminished signal integrity, altered programmed parameters, diminished battery status, inability to communicate or be reprogrammed. No sensations of tugging or warmth at the implant site were noted. Conclusion: MRI was performed in ILR patients without harm to the patient or permanent damage to the ILR. MRI scanning of the Reveal appears safe. Artifact mimicking an arrhythmia was common, however, and must be excluded in any ILR patient undergoing MRI to avoid mistakenly attributing a syncopal episode, or palpitations to the artifacts produced from MRI exposure.