Featuring: Igor Efimov, PhD
Soft, wireless implant monitors the heart without requiring removal
Nearly 700,000 people in the United States die from heart disease every year, and one-third of those deaths result from complications in the first weeks or months following a traumatic heart-related event.
To help prevent those deaths, investigators at Northwestern and George Washington (GW) universities have developed a new device to monitor and treat heart disease and dysfunction in the days, weeks or months following such events, according to new research published in Science Advances. And, after the device is no longer needed, it harmlessly dissolves inside the body, bypassing the need for extraction.
About the size of a postage stamp, the soft, flexible device uses an array of sensors and actuators to perform more complicated investigations than traditional devices, such as pacemakers, can accomplish. Not only can it be placed on various sections of the heart, the device also continuously streams information to physicians, so they can remotely monitor a patient’s heart in real time. The device is also highly transparent, allowing physicians to observe specific heart regions to make a diagnosis or provide a treatment.
“Several serious complications, including atrial fibrillation and heart block, can follow cardiac surgeries or catheter-based therapies,” said Northwestern’s Igor Efimov, PhD, a professor of Biomedical Engineering in the McCormick School of Engineering and of Medicine in the Division of Cardiology, and an experimental cardiologist, who co-led the study. “Current post-surgical monitoring and treatment of these complications require more sophisticated technology than currently available. We hope our new device can close this gap in technology. Our transient electronic device can map electrical activity from numerous locations on the atria and then deliver electrical stimuli from many locations to stop atrial fibrillation as soon as it starts.”
“Many deaths that occur following heart surgery or a heart attack could be prevented if doctors had better tools to monitor and treat patients in the delicate weeks and months after these events take place,” added GW’s Luyao Lu, PhD, who co-led the work with Efimov. “The tool developed in our work has great potential to address unmet needs in many programs of fundamental and translational cardiac research.”
Lu is an assistant professor of biomedical engineering at GW and Efimov is a member of the Robert H. Lurie Comprehensive Cancer Center of Northwestern University.
This work builds on Efimov’s previous work to develop cardiac implants to monitor and temporarily pace the heart. In 2021, Efimov and Northwestern professor John A. Rogers, PhD, a professor in the McCormick School of Engineering, and of Dermatology and Neurological Surgery, introduced the first-ever transient pacemaker, published in Nature Biomedical Engineering. Then, earlier this year, Efimov’s team unveiled a graphene “tattoo” for treating cardiac arrhythmia, published in Advanced Materials.
“After heart surgeries, surgeons sometimes insert temporary wires, which are connected to external current generators, to provide electrical stimulation during temporary heart block caused by the surgery,” Efimov said. “Recently, we developed a bioresorbable pacemaker to replace such a wire. Post-operative atrial fibrillation requires a more complicated approach based on a multi-electrode array for sensing and stopping atrial fibrillation. Now, we present a novel technology to achieve this goal.”
Tested in small animal models, the new device provides functions beyond those of a traditional pacemaker. While a pacemaker only can provide one overall picture of the heart (whether or not the heart is beating), the transient device provides a more nuanced picture. Not only can it restore normal heart rhythms, it also can show which areas of the heart are functioning well and which areas are not. The device’s transparent nature also allows investigators to optically map many important cardiac physical parameters through the device to better study heart function and heart disease mechanisms.
After a clinically relevant period, the device — which is made of biocompatible materials approved by the U.S. Food and Drug Administration — simply dissolves into benign products. Similar to absorbable stitches, the device degrades and then completely disappears through the body’s natural biological processes. The device’s bioresorbable nature could reduce healthcare costs and improve patient outcomes by avoiding complications from surgical extraction and lowering infection risks.
The study was supported by the National Science Foundation and the National Institutes of Health.
This article was originally published in the Feinberg School of Medicine News Center on July 24, 2023.
Igor Efimov, PhD, a professor of Biomedical Engineering in the McCormick School of Engineering and of Medicine in the Division of Cardiology, was co-senior author of the study in Science Advances.
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