Medtronic is seeking regulatory approval for a pacemaker that's compatible with MRIs.

[JoyBridges]

In all of medical technology, few products have been as enduring as the pacemaker.

The device, which paces a heart that beats too slowly, has saved countless lives and enjoyed an extraordinary run, as medical devices go, and has helped build Minnesota's formidable medical economy.

But in the past decade or so, an unsettling truth has emerged about pacemakers, something none of its inventors could have imagined: Patients implanted with the silver-dollar-sized device are warned against getting MRI scans. The interaction between the tiny battery-powered devices and the powerful magnetic imagers is seen as terribly risky, and potentially harmful.

Now, Medtronic Inc. has developed a pacemaker system that is MRI-compatible under most circumstances. Its competitors are working on their versions, as well.

Already approved in Europe, Fridley-based Medtronic's Revo MRI Pacemaker System will be evaluated by a Food and Drug Administration (FDA) panel of experts on March 19. If the device clears the panel, it's likely the agency will approve it for sale in the United States.

In the evolution of pacemaker technology, this advance looms large -- and potentially could spread to other devices implanted in the body that react with MRI scans.

"Fifty years ago, no one thought about the use of MRIs and now it's become commonplace," said Dr. David Steinhaus, medical director of Medtronic's cardiac rhythm disease management business. "More and more, these patients who get pacemakers are going to need MRIs, so the ability to do MRIs on these patients will be really important."