Swiss scientists have designed a turbine that can fit in human arteries and generate enough power to recharge pacemakers, IEEE Spectrum reports.
The heart is a pump in a prime location, brimming with energy for the taking, says study researcher Alois Pfenniger from the University of Bern. It produces about 1 or 1.5 watts of hydraulic power, and “we want to take maybe one milliwatt,” he adds.
A pacemaker only needs around 10 microwatts.
They tested 3 off-the-shelf turbines in a tube designed to mimic the millimeters-wide internal thoracic artery, which supplies the chest and breasts.
The most efficient of the turbines they tested produced around 800 microwatts (that’s 80x what a pacemaker needs).
All kinds of implantable medical devices – like blood-pressure sensors, drug-delivery pumps, or neurostimulators – could benefit from an independent power supply. Many people already have these sorts of implants, but each still requires a replaceable battery or a cable to keep the power flowing.
Miniaturizing these devices and eliminating cables could allow surgeons to implant them in ways that improve blood flow, reduce side effects, and add new functions. Self-contained devices could also monitor vital signs with unprecedented continuity.
But the turbine’s turbulence could provoke a life-threatening blood clot, since blood that gets trapped in those vortexes would coagulate.
Some other groups have tried to address this problem:
- A design by Paul Roberts of Southampton University Hospitals NHS Trust doesn’t have a rotating part in the path of the blood flow. Instead, it’s attached to a pacemaker lead, and it works by using the blood pressure changes of a heart beating to move a magnet back and forth. However, a prototype tested in a pig produced only about one-fifth of the energy a pacemaker needs.
- A device from Dan Gelvan of Sirius Implantable Systems uses a different kind of energy conversion. But this mechanical-to-electrical energy transducer is located alongside moving organs rather than inside of an artery.
Via IEEE Spectrum.
Image: Alois Pfenniger, ARTORG Cardiovascular Engineering, University of Bern, Switzerland