Abstract 15828: No Persistent Significant Risks Observed With Both Thoracic and Non-Thoracic Magnetic Resonance Imaging in the Presence of Implanted Cardiac Rhythm Devices
Introduction: Magnetic resonance imaging (MRI) may provide important and potentially life-saving information for patients with implanted cardiac devices. A protocol was developed at the Intermountain Medical Center to evaluate the risk of MRI at 1.5 Tesla for clinically-indicated patients with pacemakers and implantable cardioverter-defibrillators (ICD) for both thoracic and non-thoracic imaging.
Methods: An MRI was considered only when other noninvasive imaging was unable to provide diagnostic test results. MRI scanning consisted of the minimal number of scanning sequences necessary for clinical needs. Device interrogation was performed both pre and post MRI. Pacemaker patients that were pacemaker-dependent were programmed to an asynchronous pacing mode. ICD patients who were pacemaker-dependent were excluded, while those who were non-pacemaker dependent had tachyarrhythmia therapies turned off. Noninvasive monitoring of ECG, pulse oximetry, blood pressure, and verbal communication was performed during MRI. Study endpoints were device failure, loss of capture, electrical reset, induced arrhythmias, or clinically significant device programming changes.
Results: Between January 2006-2010, 104 MRI scans involving 71 pacemakers and 33 ICDs were performed. These included 17 cardiac and 11 T-spine MRI studies. Serial scans on different days were performed in 12 patients. No device failures, loss of capture, electrical reset or clinically significant device programming changes were observed. One patient showed a pacing lead impedance rise of over 50 ohms. One patient developed a nonsustained episode of atrial fibrillation while another showed a nonsustained wide complex tachycardia that stopped when the exam was stopped. One Biotronik pacemaker patient felt uncomfortable warming at the pacemaker site and the MRI was discontinued. No deaths were observed.
Conclusions: In patients with implanted cardiac devices, clinically-indicated thoracic and nonthoracic MRI at 1.5 Tesla performed under carefully controlled conditions were associated with no adverse events, electrical reset or clinically significant device programming changes suggesting that all fields of MRI imaging can be safely performed in device implanted patients.
- © 2011 by American Heart Association, Inc.