Pacemakers Get an Upgrade

February 21, 2023

Jim Allen knew something wasn’t right. He’d been walking at least 10,000 steps a day as part of a fitness program, but now was experiencing fatigue. He couldn’t take his walks, and he was also tired just sitting around.

After wearing a heart monitor for a month, he had the answer. His heart rate was extremely low, a condition known as bradycardia. At age 58, Allen’s should’ve been between 60 and 100 beats per minute. “It was running in the 30s at night and in the 50s during the day,” he said. “I was really, really tired all the time.”

Mercy doctor's coat A look at Jim Allen's pacemaker.


With his heart beating so slowly, oxygen wasn’t circulating through Allen’s body efficiently, leading to his fatigue. That’s typically when surgeons implant a pacemaker, a device that became commonplace in the 1970s. It contains a battery and electrical circuitry, connected to the heart through wires, or leads. The pacemaker sends impulses to the heart when the natural “wiring” isn’t telling the heart to beat fast enough.

Now, Mercy doctors are able to implant the tried-and-true technology in an entirely new, more natural way.


“The FDA just approved what’s known as ‘conduction system pacing’ late last year,” said Dr. Indrajeet Mahata, Mercy cardiac electrophysiologist. “The new lead and system work with the God-given architecture of the heart. We map the natural heart wiring in real time and implant the lead where those impulses originate so the artificial impulses can produce regular contractions.” 

Mercy doctor's coat The leads implanted in the heart.

The new type of pacing helps patients avoid complications that can be associated with traditional pacing methods, including cardiomyopathy, when the heart thickens and can no longer pump efficiently.

“I think within the next five years, this will be the way everyone is implanting pacemakers,” Dr. Mahata said. “We knew our patients could benefit from it, which is why we were ready to bring it to them right after Food and Drug Administration approval.”

As for Allen, less than a month after surgery, his life is already improving. “It took a couple of days after surgery for me to feel the difference, but now I can tell,” he said. “I can’t wait for warm weather so I can get back to the activities I used to enjoy with less fatigue.”