Cardiac rhythm management devices in a magnetic resonance environment

Abstract

MRI is the gold standard diagnostic tool for soft tissue imaging for many specialties. An impressive body of research has proven the effectiveness of cardiac rhythm management devices (CRMDs) objectively, in terms of parameters that include patient's quality of life, morbidity, and mortality. However, interaction between CRMDs and MRI scanners is a problem. Static main magnetic field, radiofrequency energy and the gradient magnetic field are three distinct mechanisms related to MRI and cause risks to CRMDs. Very often, patients with CRMDs have been excluded from undergoing MRI scans despite the fact that these scans were critical for the diagnosis and therapy of patients with serious medical conditions. In order for all patients with CRMDs to have the ability to perform this exam, the industry works hard to design devices that are MRI conditional.

Keywords::

• cardiac rhythm management device
• MR conditional
• MR safe
• MR unsafe
• MRI

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• MRI is the gold standard diagnostic tool for soft tissue imaging for many specialties.

• Cardiac rhythm management devices (CRMDs) have proved their effectiveness objectively, in terms of parameters that include patient's quality of life, morbidity and mortality.

• Static main magnetic field, radiofrequency energy and the gradient magnetic field are three distinct mechanisms related to MRI and arise risks for CRMDs.

• It is estimated that up to 75% of pacemaker patients will have a medical need for an MRI over their lifetime.

• MRI conditional is a CRMD that has been demonstrated to pose no known hazards in a specified MR imaging environment with specified conditions of use.

• MRI safe is a CRMD that poses no known hazards in any MR environment.

• The most recently developed MR conditional cardiac device is the Advisa MRI™ SureScan™ Pacemaker, along with CapSureFix MRI SureScan leads by Medtronic, Inc., Minneapolis, MN, USA, which received US FDA approval on 13 February 2013.

• The first FDA-approved MR conditional pacing system in the USA was the Medtronic EnRhythm MRI™ SureScan™ pacing system and associated CapSureFix MRI™ SureScan^® leads.

• European Society of Cardiology foreseeing the problem of increasing patients with CRMDs and increasing MRI exams announced suggestions for device programming when MRI is required.

• European Society of Cardiology reports suggestions for devices programming when MRI is required. MRI of patients with CRMDs may be considered but with caution and with the benefits outweighing the risks of the examination.