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A comment on New generation artificial heart implanted in patient. Parent comment

Re:New generation artificial heart implanted in patient by aetherspawn on Friday July 16, 2021 @03:40AM (#27853867)
I have a feeling there isn’t enough power in nuclear at the scale that would fit inside the body with sufficient shielding. Nuclear is surely for low power devices, but human hearts would actually use a great deal of power (estimate 50-100W). It won’t last for years like you’d expect.

Even if you _can_ package it, still needs batteries for redundancy and clearly those don’t fit inside either. Patients with batteries carry around massive backpacks.

Brings a new meaning to ‘having a meltdown’ though. Overheating nuclear heart would literally boil your blood.

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Re:New generation artificial heart implanted in patient by Someone on Friday July 16, 2021 @04:05AM (#27853970)
On https://hypertextbook.com/facts/2003/IradaMuslumova.shtml, the highest estimate there is 5W, and that’s an outlier on that page.

That may be because of the difference between output power and input power needed to produce it. One citation there says the mechanical efficiency of the heart is about 20%.

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Re:New generation artificial heart implanted in patient by iancmceachern on Friday July 16, 2021 @01:37PM (#27858859)
Exactly, the human heart is a marvel of design and performance.

Typically these devices use between 10-30 watts of power for each side of the heart (in the LVAD case). For an artificial heart (which is two LVADs, basically a LVAD and a RVAD) it's more like 30-60 watts of continuous power.

The human heart is amazing.

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Re:New generation artificial heart implanted in patient by aetherspawn on Friday July 16, 2021 @05:08AM (#27854370)
It’s pretty easy to calculate if we knew how long the battery lasts. We can estimate the size of the battery from the weight of the backpack (6kg) and use the time to flat to estimate the power draw - that’s the actual electrical energy usage of the heart.
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Re:New generation artificial heart implanted in patient by marcan_42 on Friday July 16, 2021 @05:53AM (#27854599)
A heart uses nowhere near 100W of power. That's about the overall power consumption of the entire human body at rest.
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Re:New generation artificial heart implanted in patient by aetherspawn on Friday July 16, 2021 @11:32PM (#27863379)
My estimation was based on a value that is a fraction of the smallest brushless automotive water pump that I work with, which is smaller than a heart and barely suits a go kart.
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