Cardiac pacemakers and other implantable medical electronic devices are powered by batteries that eventually weaken and must be replaced. Advances in the science of microcircuitry and better battery technology have brought to market the small and long-lasting devices that are today's state of the art. Battery life continues to be the limiting factor for these devices.

Stores are full of common devices that utilize "the Faraday effect" (electromagnetic induction) to generate enough power for a few minutes of radio or LED light. These manually powered induction chargers create current by shaking a tube or spinning a crank within which are magnets and a wire coil. A few seconds of movement give the internal battery enough of a charge to power a device for some minutes. The limiting factor of induction chargers is, you might guess, power to move them. Luckily, a few seconds suffice to create stored power, or you'd find your arm grew very tired in the process.

One's heart is, in essence, a perpetual motion machine. Powered by metabolically-derived picovolt capacitative discharges across membranes, biomechanical activity triggers local responses across millions of cells. The effect is to make organisms what they are, independent of their cellular environment, a sum greater than the whole of its parts. When organism meets medical device, the outcome is dependence by the organism on the quality of its devices. Third party intervention is needed to keep the recipient of a medical device on schedule for preventive maintenance and battery replacement. A recharger for medical device batteries would prolong recipients' independence appreciably.

Acknowledging the vast power of the beating heart, I propose to tap that resource for power generation. Ring the heart or its pericardium with a hula hoop instantiated with microcircuitry and magnets mounted on slides within. Each heartbeat twists the hoop, moving the magnets inside, and the mechanical process generates a second of electromagnetic induction. The resulting power gathered in coils attached to the hoops' microcircuitry is channeled back to a device battery by way of recharging circuitry. In effect, the heart powers its own trickle charger.

Users might free themselves from the need for follow up surgery by a few or by many years, if pacemaker battery power output matches the feedback produced within their induction hoop.
-- reensure, Aug 10 2006

Better yet... http://www.isralert...israeli_researc.php
just another alternative, but probably more costly... [tallbrownie, Aug 10 2006]

The Forever Flashlight http://www.plowhear...r_index=&pcode=7380
"Keep this product at least one foot away from medical devices such as pacemakers due to the strong magnetic field generated by the product." [Klaatu, Aug 10 2006]

Aug. 9 issue of the ACS journal Nano Letters http://www.scienced...08/060820192933.htm
"Pizoelectric and Semiconducting Coupled Power Generating Process of a Single ZnO Belt/Wire: A Technology for Harvesting Electricity From the Environment" [reensure, Aug 21 2006]

Beautifully conceived. Dunno whether it would work, but [+] anyway.
-- pertinax, Aug 10 2006


how about you bypass the battery stage. The electric current formed by the heartbeat could be slightly delayed by an electronic circuit (by the period of time between the last two heartbeats, usually about 1 second); the delayed signal then used to stimulate the heart.
-- xaviergisz, Aug 10 2006


I think so. Most devices operate by "demand" to a degree, and healthier recipients demand a lower percentage of output than higher demand users. Devices utilize stored power at a constant low draw to monitor homeostatic functions, but draw more power to intervene, i.e. transmit a signal.
-- reensure, Aug 10 2006


This reminds me of a drfowler story. When doing her residency she was in the morgue and a body kept shaking or something. She thought it was odd but natural, after a while she started to freak out and called the ER doc...he came down to check the body out. He simply took a magnet and ran it across the chest...someone had forgotten to remove or turn off the pacemaker. lol

This is a good idea if it saves lives. I will give you a cookie, or a bun...whatever it is.
-- tallbrownie, Aug 10 2006


This really sounds like it would work. Great! Does anyone know about the method of recharging 'phones using body electricity? Could that be applied here?
-- nineteenthly, Aug 10 2006


I'm thinkin' a small one of those shakin' flashlight magnet/coil type arrangments might fit on the inside of an arm bone. Might look a little silly... I suppose it could be in the lower leg, the magnet resting on a spring inside the coil such that the shock of each step caused the magnet to oscillate inside the coil...
-- half, Aug 10 2006


You could always put one of those in a body part that tends to vibrate a lot anyway, then you wouldn't need to jiggle it yourself.
-- nineteenthly, Aug 10 2006


I hate to burst your bubble. 10 years as a trauma tech taught me that magnets and pacemakers only go together when you want to change the pacing. The pacemakers are set up to be calibrated through the skin by magnet. Bring a magnet near your Gramma Harriet's pacemaker and wait for the fun to start. Great idea, but it can't work. [-]
-- Klaatu, Aug 10 2006


How close to the heart is a pacemaker installed? Not that I'd recommend taking the chance on strapping anything on to even my perfectly healthy heart, just curious. As goofy as it is, I'd rather go with the solution I proposed, given some absurdly strange world where those were my only choices.

It wouldn't take much of a magnet to induce a tiny charge. Over a long time this might technically provide enough power. The magnets in those "forever flashlights" are very powerful. The ones in the proposed idea wouldn't have to be as strong.
-- half, Aug 10 2006


Pacemakers are generally installed under the left clavical, just under the skin. A magnet in the leg would be far enough away. I just don't think I would want a wire running from my leg all the way to my chest.

All pacemaker users are cautioned about *any* magnetic source.
-- Klaatu, Aug 11 2006


[tallbrownie] if you don't mind me asking, have you been a halfbaker with a different moniker in the past

<later edit> I just read your anno to Dr. Fowler, I get it now.
-- 2 fries shy of a happy meal, Aug 11 2006


<pacemaker patient> I pledge allegiance to the flrgz of the Untied Sthgzds (thud) (falls over in a clump) </pacemaker patient>
-- csea, Aug 11 2006


Cerebrospinal fluid is sometimes drained into the stomach via a permanently implanted cannula, which is not too dissimilar to a wire running from the heart to the leg.
-- nineteenthly, Aug 11 2006


Cerebrospinal fluid is sometimes drained into the stomach via a permanently implanted cannula, which is not too dissimilar to a wire running from the heart to the leg.
-- nineteenthly, Aug 11 2006


Does the cannula make one stutter?
-- Klaatu, Aug 11 2006


// .. Cerebrospinal fluid is sometimes drained into the stomach via a permanently implanted cannula

One possible treatment of hydrocephalus or pseudotumor cerebri. Do you suggest to avoid the chest and to seek the use of an alternate site of muscular activity?
-- reensure, Aug 15 2006


what about using the iron circulating in the blood to power something? Maybe if you create a coil of blood vessels somewhere?
-- wittyhoosier, Aug 21 2006


You're talking about a film of hemoglobin, [wittyhoosier]? Used as an array of ion channels, perhaps?

Now, I __know__ you weren't talking about running an electrical current, DSL style, through the body's blood stream. Careful now, thinking like that will piss off [Klaatu].
-- reensure, Aug 22 2006



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