Using the heart to power pacemakers
The heart is the most essential human organ, regulating blood flow to every other part of the body. Engineers at Dartmouth College’s Thayer School of Engineering have developed a device that can convert the kinetic energy of this important organ into electricity to power implantable devices.
Millions of people rely on pacemakers, defibrillators, and other vital implants that run on batteries that need to be replaced every five to 10 years, a complicated and expensive procedure that puts patients at risk for infection.
"We're trying to solve the ultimate problem for any implantable biomedical device," said Dartmouth engineering professor and lead researcher on the project John X. J. Zhang in a press release. "How do you create an effective energy source so the device will do its job during the entire lifespan of the patient, without the need for surgery to replace the battery?"
Funded by the National Institutes of Health (NIH) and published as the cover story for Advanced Materials Technologies, the study was a three-year collaboration between researchers at Dartmouth and clinicians at University of Texas Health San Antonio.
The team invented a dime-sized modification to existing pacemakers that continually charges their batteries using a lead wire that converts kinetic energy from the heart. They introduced a thin polymer piezoelectric film called PVDF which, when designed with porous structures, can convert small mechanical motion to electricity. In addition, the same technology has potential for integration with sensors to allow doctors to monitor patients’ conditions in real time.
"Of equal importance is that the device not interfere with the body's function," said Dartmouth researcher and first author Lin Dong. "We knew it had to be biocompatible, lightweight, flexible, and low profile, so it not only fits into the current pacemaker structure but is also scalable for future multi-functionality."
Engineers estimate that the technology is around five years away from commercialization. The team will use the next two years of their NIH funding to complete the pre-clinical process and obtain regulatory approval.
"We've completed the first round of animal studies with great results which will be published soon," said Zhang. "There is already a lot of expressed interest from the major medical technology companies, and Andrew Closson, one of the study's authors working with Lin Dong and an engineering Ph.D. Innovation Program student at Dartmouth, is learning the business and technology transfer skills to be a cohort in moving forward with the entrepreneurial phase of this effort."