FDA Approves First "MRI-Safe" Pacemaker

Reed Miller

February 09, 2011

February 9, 2011 (Silver Spring, Maryland) — The FDA approved the first pacemaker specifically designed to be safe with magnetic resonance imaging scans [1].

Following the unanimous advice of its advisory panel, the agency yesterday approved Medtronic's REVO MRI pacemaker system with CapSureFix MRI SureScan leads, formerly called EnRhythm MRI. Specifically, the REVO MRI SureScan is approved for rate-adaptive pacing and dual-chamber pacing, according to the FDA's approval letter. Shipments of Revo MRI will begin immediately, according to the company.

The system is designed for patients who may need to undergo an MRI scan. REVO's SureScan function prepares the device for the MRI environment, and the CapSureFix MRI SureScan leads are versions of Medtronic's CapSureFix Novus active-fixation leads with modified internal wiring to decrease the risk of overheating during an MRI scan. Previously, MRI has been contraindicated for patients with a pacemaker.

The approval is based primarily on the company's 484-patient trial that randomized patients with the device to undergo or not undergo an MRI.  None of the patients scanned with MRI showed any MRI-related complications, confirming the results of animal studies and computer modeling. The study measured changes in the pacemaker's pacing capture threshold (PCT) as the indicator of myocardial damage associated with lead heating during an MRI.

As a condition of approval, Medtronic has agreed to file annual reports with detailed data on the performance of all implanted REVO MRI SureScan systems. The company has also agreed to conduct a five-year global, nonrandomized cohort study of patients implanted with the device. The study will include a chronic lead performance arm of 1810 patients to characterize the chronic performance of the pacemaker leads. The study will also include an arm with patients undergoing MRI to test whether the MRI-related complication rate is less than 2%.