Author: Steven Leung

Publish Date: 12/1/17

In the current era, there are many different types of cardiac implants placed inside a patient.  These include and not limited to: coronary stents, heart valves (e.g. Transcatheter Aortic Valve Replacement ), heart valve prosthesis (e.g. MitraClip), septal occluder devices, left atrial appendage occlude/clips (percutaneously or surgically implanted), implantable loop recorders, pacemakers, Implantable Cardiac Devices.  Many of these devices are safe for cardiac MRI under specific conditions.  A comprehensive list of devices that are MRI safe or conditional can be found at http://www.mrisafety.com. 

Each MRI site may have different sets of guidelines in scanning patients, who have non MRI-conditional pacemakers or ICDs.  For patients with non MRI-conditional devices, it is best to discuss with the department performing the scan first before sending a patient for the MRI scan.

Since many of these devices are placed inside or near the heart, even if MRI can be performed safely, these devices can cause significant amount of artifacts that precludes evaluation of cardiac structures of interest (Figure).  Many of these cannot be predicted until the patient is being scanned, or particular sequences are used.  These artifacts can make the study non-diagnostic, and the patient should be informed of such possibility as well.

 Figure Legend: Large artifact from the ICD obscuring the left ventricle.

References:

1. Nazarian S, Hansford R, Roguin A et al. A Prospective Evaluation of a Protocol for Magnetic Resonance Imaging of Patients with Implanted Cardiac Devices.  Ann Intern Med. 2011;155:415-424
2. Sasaki T, Hansford R, Zviman MM et al. Quantitative Assessment of Artifacts on Cardiac Magnetic Resonance Imaging of Patients with Pacemakers and Implantable Cardioverter-Defibrillator. Circ Cardiovasc Imaging 2011;4:662-670.
3. Nazarian S. Beinart R, Halperin HR.  Magnetic Resonance Imaging and Implantable Devices. Circ Arrhythm Electrophysiol. 2013;6:419-428