Even today, a baby born with congenital heart disease might need a pacemaker early on, and would have to get a new one implanted again and again over the course of his life.
These days, pacemakers last anywhere from about five to 12 years using lithium-iodine cell batteries.
Implanting the device is often considered a routine procedure for the growing population of patients who get them. In 1993, there were just over 121,000 pacemaker implantations in the United States, according to a 2012 study in the Journal of the American College of Cardiology. Last year, about 320,000 people got pacemakers, according to device-maker Medtronic—that's an increase of more than 60 percent over two decades.
More people getting pacemakers translates to more business for companies like Medtronic, which says it makes half of the world's pacemakers. But Calkins, the doctor at Hopkins, says requiring new pacemakers every 10 years isn't about protecting financial interests through planned obsolescence. The thing is: A decade is a really long time in medical years.
"And the reality is, every time your pacemaker runs out, you don't just replace the battery," Calkins told me. "You replace the whole pacemaker. You may say, 'This seems fairly wasteful. Why don't we just put in a new Duracell battery?' But there are always advances in pacemakers. The technology keeps getting better. They are smaller, they last longer, they have more of an ability to communicate with programmers."
In other words, pacemakers may seem outdated battery-wise, but they're actually heading in the same direction as most wearable gadgets: Data-driven and responsive to the behaviors of the person who is wearing—or in this case implanted with—the device.
Some pacemakers already have responsive capabilities. They can be set to recognize when a person's working out—so they'll automatically keep her heart beating at, say, 155 beats per minute while she jogs. "Pacemakers are just sort of a safety net, if you will," Calkins said. "[They set the rate] below which your heartrate can't go any slower, in case our own body's pacemaker's is starting to get sluggish."
Activity-specific heart-rate programming is standard with today's pacemakers. But Mike Hess, device president of research and development for the pacemaker division at Medtronic, says the pacemaker of the future will be even more sophisticated. Scientists are looking for more useful applications for the huge trove of data that pacemakers collect about people implanted with them. The idea is to figure out how that data—coupled with data from other monitors and devices—might contribute to more comprehensive understanding of a person's health.
"One area that a lot of people have interest in is how you integrate this implantable tech because these devices that are implanted have a unique front-row seat," Hess said. "How you link all of this data is a big area of focus for the future."