Most of the mechanical pumps we use everyday are rotary pumps. They have an impeller, or propeller or something that sits on the end of the shaft of an electric motor and spins at high speed (thousands of revolutions per minute (RPM)). There might be pulsations in the fluid being pumped due to the impact of a blade of the impeller, but they are minuscule in amplitude and much higher in frequency than the kind of pulsations you get from any kind of reciprocating pump, or a biological heart.
Now there is an artificial heart in development that has more in common with everyday rotary pumps and not much in common with a heart. There were two concerns about using a rotary pump. One is the lack of a pulse, and the other is damage to the blood cells caused by the blades whirling around. Turns out neither one seems to be much of an issue.
This new, and so far experimental, heart requires power, but it only needs a little electricity and that can easily be supplied by a battery similar to one from a laptop computer. It's small enough you can carry it around with you.
Now we're getting into the realm of science fiction. This reminds me of Dune where the bad guy had heart plugs installed in all his minions. If one of his people displeased his, the baddy could kill him by simply pulling his plug. Of course, we have lot's of ways to kill people, and some of them aren't any more difficult than flipping a switch. Pulling the plug, I dunno, that just seems kind of slippery to me.
From the PopSci story:
"As many as five million Americans suffer some form of heart failure, but only about 2,000 hearts a year become available for transplant."I kind of doubt that all five million are candidates for an artificial heart, but there is certainly a market for thousands per year.
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