The U.S. Food and Drug Administration today approved the first heart pacemaker designed to be used safely during certain magnetic resonance imaging (MRI) exams.
Pacemakers are surgically implanted medical devices that generate electrical impulses to treat irregular or stalled heart beats. MRIs use a powerful magnetic field, radio frequency pulses and an internal computer to produce detailed images of organs, soft tissues, bone, and other internal body structures not available with other imaging methods.
About half of all patients with pacemakers may require an MRI, but are advised not to have one because an MRI's magnetic and radiofrequency fields can disrupt the pacemaker's setting or cause wires to overheat, resulting in unintended heart stimulation, device electrical failure, or tissue damage.
The Revo MRI SureScan Pacing System includes a function that is turned on before a scan to prepare patients for the MRI. The pacemaker's use in MRIs is limited to certain patients, certain parts of the body, and certain scanning parameters. The FDA also is requiring training for cardiologists and radiologists who use the system.
"FDA's approval of the Revo pacemaker represents an important step forward toward greater device innovation," said Jeffrey Shuren, M.D., director of the FDA's Center for Devices and Radiological Health. "Those patients who meet the parameters for the device will be able to maintain their critical cardiac therapy while benefiting from the precise diagnostic capability of an MRI."
The FDA reviewed results from one clinical trial of 484 patients. Of those, 464 were successfully implanted with the device and then randomized to receive or not receive an MRI. None of the 211 who underwent an MRI experienced an MRI-related complication. The clinical results confirmed earlier data from animal studies, computational modeling, and other nonclinical research.
Revo is manufactured by Medtronic Inc. of Mounds View, Minn.