A 14-electrode-pair cuff resolved heart and larynx sectors of the human vagus nerve in a pilot procedure
A 14-electrode-pair cuff resolved heart and larynx sectors of the human vagus nerve in a pilot procedure
On September 14, a team from University College London demonstrated a temporary battery-free implant that receives power and pulse parameters (amplitude, duration, and frequency) over NFC, the same technology behind contactless phone payments. The device cycled through all sectors of a cuff wrapped around the cervical vagus nerve, first in four pigs, then over 30 minutes during surgery in one human subject.
The vagus nerve is a thick trunk connecting the brain to the heart, lungs, larynx, stomach, and intestines: roughly 80% of its fibers carry signals from organs to the brain, while 20% carry commands from the brain to muscles. Stimulation of this nerve is already used to treat drug-resistant epilepsy and depression and is being studied for arthritis and diabetes. A standard electrode, however, wraps around the entire trunk, and alongside the intended effect it activates neighboring fibers: patients develop hoarseness, shortness of breath, and skin tingling, forcing clinicians to reduce current intensity at the expense of therapeutic benefit. To avoid this, the new paper proposes first identifying the nerve sector responsible for the target function and delivering current only there.
A flexible cuff is placed around the nerve for this purpose: 14 independent electrode pairs are arranged around its circumference, with one additional channel spanning the entire trunk. The device has no battery: an external unit sets power and pulse parameters over NFC, and the wireless design allows the cuff to be placed and removed during surgery without a separate procedure for a battery. The cuff cycles through channels in sequence, like tuning an old radio: recordings of heart rate and laryngeal activity reveal which sector governs which function. In the future, the authors plan to build fiber visualization into the cuff so the relevant sector can be found immediately, without cycling through channels. A comparable cross-sectional nerve map was already presented in July by the Feinstein Institutes atlas: 60 nerves, 30 donors.
In an acute experiment on four pigs, this sector-by-sector sweep produced a mean selective heart rate reduction of 23.28%. The portable device replicated the effect of the previous bulky laboratory setup.
The cuff was placed during the first 30 minutes of a surgery to implant a stimulator for epilepsy treatment. Stimulation of channels 8 through 10 slowed the heart rate, most strongly in channel 10, by 7.5%, while channels 1 through 7 and 11 through 14 slightly accelerated it. This pattern reflects the same two fiber types: motor fibers slow the heart, sensory fibers accelerate it. The strongest laryngeal response fell on the opposite part of the same circumference, with the centers of the two responses separated by 231 degrees. The heart-slowing sector is distinct from the laryngeal one, and current can be directed to it selectively. The authors link this selectivity to potential future heart failure therapy and describe it as an inference drawn from a single pilot case.
The idea grew from a 2024 study by the same group in pigs: trial stimulations were compared with microtomography (an X-ray cross-section of the nerve), revealing that cardiac fibers and sensory cardiopulmonary fibers occupy different parts of the cross-section. The new device carries this finding from a laboratory bench into the brief window of a surgical procedure.
In the trial registry, the primary outcome is defined as a map of organ-specific sectors of the cervical nerve: the study plans to enroll 50 participants, and the map is to be linked to stimulation protocols. The cuff is suitable only for short-term use: testing showed that the encapsulation degrades from corrosion, and for a permanent implant the authors plan ceramic packaging.