Safety of magnetic resonance imaging of patients with a new Medtronic EnRhythm MRI SureScan pacing system: clinical study design

Richard Sutton,Inge Jenniskens,Torsten Sommer,Bruce L Wilkoff,Roger Luechinger,Michael Hull,David Bello,Emanuel Kanal

doi:10.1186/1745-6215-9-68

Richard Sutton, Inge Jenniskens + Show 6 more

Open Access

PDF Available

https://doi.org/10.1186/1745-6215-9-68

Copy DOI

Export

Save

Cite

Abstract
Highlights/Summary
Full-Text PDF
Similar Papers

Abstract

Listen

BackgroundMagnetic Resonance Imaging (MRI) of patients with implanted cardiac devices is currently considered hazardous due to potential for electromagnetic interference to the patient and pacemaker system. With approximately 60 million MRI scans performed worldwide per year, an estimated majority of pacemaker patients may develop an indication for an MRI during the lifetime of their pacemakers, suggesting that safe use of pacemakers in the MRI environment would be clinically valuable. A new pacing system (Medtronic EnRhythm MRI™ SureScan™ and CapSureFix MRI™ leads) has been designed and pre-clinically tested for safe use in the MRI environment. The EnRhythm MRI study is designed to confirm the safety and efficacy of this new pacing system.MethodsThe EnRhythm MRI study is a prospective, randomized controlled, unblinded clinical trial to confirm the safety and efficacy of MRI at 1.5 Tesla in patients implanted with a specifically designed pacemaker and lead system. The patients have standard indications for dual chamber pacemaker implantation. Successfully implanted patients are randomized in a 2:1 ratio to undergo MRI (MRI group) or to have no MRI scan (control group) at 9–12 weeks after pacemaker system implantation. Magnetic resonance (MR) scanning includes 14 head and lumbar scan sequences representing clinically relevant scans while maximizing the gradient slew rate up to 200 T/m/s, and/or the transmitted radiofrequency (RF) power up to SAR (specific absorption rate) levels of 2 W/kg body weight (upper limit of normal operating mode). Full interrogation of all device information and sensing and capture function are measured at device implantation, every follow-up and before and immediately after MRI in the MRI group and at the same time points in the control group. Complete pacemaker and lead evaluations are also done at one week and one month after the scan for the MRI and control group patients.The primary endpoint is safe and successful completion of the MRI scan as measured by freedom from both MRI-procedure related complications and clinically significant changes in the sensing and capture function of the leads.ResultsResults will be communicated after approximately 156 and 470 patients have completed 4 months of follow-up.Trial RegistrationClinicalTrials.gov identifier: NCT00433654.

Highlights

Magnetic Resonance Imaging (MRI) of patients with implanted cardiac devices is currently considered hazardous due to potential for electromagnetic interference to the patient and pacemaker system
With approximately 60 million MRI scans performed worldwide per year, an estimated majority of pacemaker patients may be indicated for an MRI during the lifetime of their pacemaker, suggesting that safe use of pacemakers in an MRI environment would be clinically valuable
Animal testing has demonstrated that the temperature at the lead tip increased up to 20°C during MRI scanning of the heart [6], which could result in tissue damage

Summary

Introduction

Magnetic Resonance Imaging (MRI) of patients with implanted cardiac devices is currently considered hazardous due to potential for electromagnetic interference to the patient and pacemaker system. With approximately 60 million MRI scans performed worldwide per year, an estimated majority of pacemaker patients may develop an indication for an MRI during the lifetime of their pacemakers, suggesting that safe use of pacemakers in the MRI environment would be clinically valuable. With approximately 60 million MRI scans performed worldwide per year, an estimated majority of pacemaker patients may be indicated for an MRI during the lifetime of their pacemaker, suggesting that safe use of pacemakers in an MRI environment would be clinically valuable. Several studies report that a small number of pacemaker patients underwent MRI scanning under controlled situations and by taking certain precautions. This was only done if the risk-benefit ratio was considered acceptable. Animal testing has demonstrated that the temperature at the lead tip increased up to 20°C during MRI scanning of the heart [6], which could result in tissue damage

Objectives

Methods

Conclusion