Medtronic Exec: Think Twice before Using Next-Gen Medical Materials

Some experts complain about the current approach of relying on tried-and-true medical device materials. They say the materials are not optimal and are holding back the medical device industry.

But not so fast, says Jennifer Miller, senior director of materials strategy and failure analysis at Medtronic's Cardiac Rhythm Disease Management business. Miller--who is scheduled to speak at MD&M East, running June 9 through 12 in New York--is all for materials innovation, but also sees value in the tried-and-true.

At least in the CRDM space, where an implantable device such as a pacemaker is expected to last up to a decade or more, designers can only predict to a point when it comes to a material's ability to withstand mechanical and chemical rigours inside the body, according to Miller.

"You can only get to a certain point, and then you have to put it in and track your product," Miller says.

So here's an interesting scenario from Miller: Surgeons need to implant a device inside your grandma. One device might be made of materials such as silicone elastomers that have a 20- or 30-year track record of reliability. Another might be made of a new polymer that is super cool--but only theoretically.

"Which one are you going to put in your grandma?" Miller says.

"That's why it's really difficult to switch materials, because you need the validity and the longevity in vivo to demonstrate that for that application, it's appropriate," Miller says. "It takes tens of millions of dollars and a lot of time and direction tracking this stuff."

And in the end, the old standby material might be used instead anyway because it's been known to be good for decades, versus years.

"This is one of the hardest things for [young people] at universities to understand. They want to invent the next great thing, and they should, and we should be aware of what's out there. And we are," Miller says. "But when it comes down to what it's used for, what's the proof of its reliability, and how do you manage the risk of using it, that becomes a very complex decision."

Michael Drues, PhD, president of Vascular Sciences (Grafton, MA; www.vascularsci.com), recently told Qmed that he thinks the lack of new materials is preventing a host of innovative 3-D printing applications and other game changers in the medical device field. And MIT-based biomaterials pioneer Robert Langer has meanwhile observed has observed that many medical materials used throughout the 20th century had been inspired by household items.

But it is worth noting that there can even be trouble when tried and true materials are used for something different. (Need a good example? Try metal-on-metal hip implants, which are costing the industry billions of dollars in lawsuit settlements.) 

"That's why you don't see a lot of materials being introduced for long-term implants. ... You want us to be conservative," Miller says.

As patients live longer, materials need to last longer, too. "That's a whole different requirement on those materials, and we're learning, 'How long does this material need to go?'" Miller says. "We would love it to go forever and ever and ever."

Chris Newmarker is senior editor of MPMN and Qmed. Follow him on Twitter at @newmarker.