The US Food and Drug Administration (FDA) approved, on 8 February 2011, Medtronic’s Revo MRI SureScan pacing system. This is the first and only heart pacemaker in the USA designed to be used safely during certain magnetic resonance imaging (MRI) exams.
According to the FDA, about half of all patients with pacemakers may require a magnetic resonance imaging exam, but are advised not to take it because 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, 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.”
J. Rod Gimbel of Cardiology Associates of East Tennessee, Knoxville, USA commented, “Providing pacemaker patients with access to MRI allows detection and treatment of serious medical conditions such as stroke, cancer, and a wide variety of important neurologic and orthopedic conditions.”
The FDA reviewed results from one clinical trial of 484 patients. Of those, 464 were successfully implanted with the device and then randomised to receive or not receive an MRI. None of the 211 who underwent a magnetic resonance imaging exam experienced an MRI-related complication. The clinical results confirmed earlier data from animal studies, computational modeling, and other nonclinical research.