FRIDAY, May 27, 2022 (HealthDay News) — Researchers are one step closer to delivering heart patients a temporary “smart” pacemaker that simply disintegrates once it’s no longer needed.
Pacemakers are devices that are implanted to control certain abnormal heart rhythms by sending electrical impulses to the heart muscle. They are usually permanent, but in some cases patients only need temporary cardiac pacing for a few days.
Researchers at Northwestern University last year reported early success in developing an alternative to the temporary pacemakers used today: a wireless, “dissolving” pacemaker made from materials that biodegrade within a few weeks.
At that point, the focus was on the pacemaker itself, said researcher John Rogers, who is leading the development of the technology.
The pacemaker is a thin, flexible device made up of an encapsulating layer that contains electrodes. The bottom of each electrode is exposed and adheres to the heart’s surface.
Now the researchers have added components that allow the pacemaker to be self-contained: a network of thin, wireless sensors and a skin-worn control unit. They work together to monitor the heart’s electrical activity and other body processes, such as the rate of breathing, and to control heart rate.
The system is also designed to detect problems such as a pacemaker malfunction and then warn the patient. Meanwhile, all this important information can be streamed to a smart device, allowing doctors to examine patients remotely.
That’s in contrast to the way temporary pacemakers work today, Rogers explained.
Traditional permanent pacemakers consist of a battery-powered pulse generator that is implanted under the skin of the chest and connected to the heart by wires called electrodes.
When patients only need a pacemaker for a short time, doctors use an external pulse generator instead of implanting one. But patients still need electrodes sewn onto the heart and fitted with wires coming out of the chest and connected to the generator.
That system works well, Rogers said, but there are small risks — like a lead becoming detached or causing an infection. Also, it keeps patients tied to hospital equipment.
According to Rogers, the wireless system could allow them to exercise and maybe recover at home.
“We envision a future where patients are discharged from the hospital sooner,” he said.
However, many works remain for the time being. The technology has so far been tested on animals and in the laboratory on human heart tissue – not yet on patients.
This latest step in its development, described May 26 in the journal Scienceprovides “proof of concept,” said Dr. Jim Cheung, a cardiologist at Weill Cornell Medicine in New York City.
“This is very interesting, creative work,” said Cheung, who also serves as chair of the governing board of the electrophysiology section of the American College of Cardiology.
He noted that they are a “niche group” of patients who need temporary stimulation. A typical scenario would be after heart surgery where a patient has a slow heartbeat for a short period of time.
Another example, Cheung said, would be patients who have to have a permanent pacemaker removed due to an infection. Temporary stimulation can be used as a “bridge” until the infection clears and a new permanent device can be implanted.
The Northwestern researchers pointed to a different scenario: newborns needing surgery because they were born with a hole in the wall separating the upper chambers of the heart. These babies will need temporary stimulation after the procedure.
Cheung said it’s conceivable that the new technology could allow patients who need temporary stimulation to be mobile or even go home earlier. He also pointed out the bigger picture: The basic premise of this technology — a wireless, intelligent system that detects problems within a given tissue and applies a treatment — could have a number of medical applications.
Rogers said that is indeed the broader goal.
The pacemaker’s dissolving function would negate the need to subsequently remove anything from the patient’s body. If that idea sounds worrisome, Rogers said the device is made from substances found in vitamin pills — like small amounts of iron, magnesium and silicon — that are safe to break down in the body.
“There’s nothing exotic about that,” he said.
The US National Heart, Lung, and Blood Institute has more on pacemakers.
SOURCES: John Rogers, PhD, Professor, Materials Science and Engineering, Biomedical Engineering and Neurological Surgery, Northwestern University Feinberg School of Medicine, Chicago and Northwestern McCormick School of Engineering, Evanston, Illinois; Jim Cheung, MD, Chair of the Board of Directors, Electrophysiology Section, American College of Cardiology, Washington, DC, and Professor of Medicine, Weill Cornell Medicine, New York City; ScienceMay 26, 2022