Pacesetter Human Tissue Stimulator (HTS) (c) David Prutchi, Ph.D., 2024
I recently acquired this device on eBay® (from a very kind seller, I may add). Although labeled as a “Rechargeable Pacemaker,” and looks just like the one at the Udvar-Hazy about which I had posted a few years ago, it is in fact a neurostimulator.
The Human Tissue Stimulator or “HTS” was developed subsequently to the rechargeable pacemaker, prompted by the clinical need for a rechargeable implantable neurostimulator.
Yesterday I visited the Udvar-Hazy Center of the Smithsonian Air & Space Museum in Chantilly, VA. There I found this demo rechargeable pacemaker being displayed as a spinoff of NASA’s technology with the following explanation:
I can’t remember exactly where I found the picture of a Pacesetter model BD102 VVI, but the story behind it is documented by Kirk Jeffrey in “Machines in our Hearts”:
“In 1968, Robert Fischell, of the Applied Physics LOaboratory at Johns Hopkins University, and cardiologist Kenneth B. Lewis had begun a collaboration that led in 1973 to a new kind of Ni-Cad battery able to function more effectively at body temperature and hermetically sealable. Alfred E. Mann, a California entrepreneur with background in the aerospace industry, had provided some financial support to the Hopkins group. Eventually Mann founded a small company to develop a pacemaker for the rechargeable battery; this was the origin of Pacesetter Systems. The rechargeable pacemaker reached the market in the summer of 1973, just as CPI introduced its lithium pacer.”
Image Credit: NeuroPace
NeuroPace is a privately-held company in Mountain View, CA. Their RNS® implantable stimulator, along with depth leads and cortical strip leads are designed for the treatment of medically refractory partial epilepsy.
On November 14, 2013, NeuroPace has now received FDA pre-market approval for the NeuroPace RNS System as a treatment for adults with partial onset seizures that have not been controlled with two or more antiepileptic drugs.
According to the press release:
The RNS System has been evaluated in three clinical trials, including a prospective, randomized, double-blinded, sham stimulation controlled pivotal study. The pivotal study primary effectiveness endpoint was met by demonstrating a 37.9 percent reduction in seizure frequency in patients treated with responsive stimulation compared to a 17.3 percent reduction in patients who were implanted with the device but were not receiving responsive stimulation during a three month blinded period. The difference is statistically significant (p=0.012). For those subjects who reached two years post-implant, 55% of the subjects experienced a 50% or greater reduction in seizures.
Unlike Cyberonics’ VNS IPGs, the RNS neurostimulator is designed to detect abnormal electrical activity in the brain and respond by delivering electrical stimulation to normalize brain activity before the patient experiences seizure symptoms. The neurostimulator is implanted in the cranium and connected to one or two leads that are implanted near the patient’s seizure focus.
Image Credit: NeuroPace
NeuroPace is a privately-held company in Mountain View, CA. Their RNS® implantable stimulator, along with depth leads and cortical strip leads are designed for the treatment of medically refractory partial epilepsy.
Unlike Cyberonics’ VNS IPGs, the RNS neurostimulator is designed to detect abnormal electrical activity in the brain and respond by delivering electrical stimulation to normalize brain activity before the patient experiences seizure symptoms. The neurostimulator is implanted in the cranium and connected to one or two leads that are implanted near the patient’s seizure focus.
NeuroPace recently disclosed that it has raised about $18 million of a planned $50 million in new funding. NeuroPace has raised about $180 million since it was founded in 1997.
Dr. Fischell received his BSME degree from Duke University and MS and Sc.D. degrees from the University of Maryland. Dr. Fischell was employed at the Johns Hopkins University where he was the Chief Engineer of the Space Department and worked on more than 50 spacecraft. His interests at Johns Hopkins then turned to the invention of new medical devices such as pacemakers and implantable heart defibrillators. Starting in 1969, Dr. Fischell began the formation of 14 private companies that licensed his patents on medical devices. These companies include Pacesetter Systems, Inc. (now called St. Jude Medical), IsoStent, Inc., NeuroPace, Inc., Neuralieve, Inc., Angel Medical Systems, Inc, and Svelte Medical Systems, Inc. Dr. Fischell is a prolific inventor with over 200 issued U.S. and foreign patents, many of which have been the basis for new medical device companies. Continue reading