
A way to charge pacemakers using the heart’s own muscle - jkuria
https://www.economist.com/science-and-technology/2019/03/23/a-way-to-charge-pacemakers-using-the-hearts-own-muscle
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Nextgrid
Just wondering why wireless charging isn’t used? A pacemaker seems to use
little energy so one overnight charge cycle should last for months if not
years?

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stuartbman
As said previously, they used to use these, but having an induction loop means
you can never have an MRI as this would superheat the coil. I'd rather have
the option of an MRI should I need it, and a daycase procedure to change my
batteries.

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amluto
I’m not sure I see the problem. If the pacemaker kept the coil shorted except
when charging, then even a fairly large AC field shouldn’t transfer much power
or induce a problematic voltage. And an MRI is mostly a DC field, which seems
mostly harmless.

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kgc
Shorted, it would still create heat.

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londons_explore
The AC fields in an MRI aren't that large.

You also don't have to short it. Leaving it open circuit with a charging
circuit that can withstand large voltages is a much better bet.

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ineedasername
Wouldn't this subtly sap the energy from the heart, making it just that little
bit harder perform every beat do due the resistance of the piezoelectric
strip? 10 microwatts seems little enough, but then how much does it take for
the heart to beat? What % increase is this over normal functioning?

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xiphias2
Google is your friend:

The heart has every other muscle in the body beat by producing between 1 and 5
watts

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ineedasername
Thanks, so I guess that's basically smaller than the margin of error if you
were sampling that

