Have a heart...

For most of my life, I’ve had minor heart palpitations. They’ve never been very serious, at their worst making me mildly uncomfortable for a few seconds, but they've always thrown me a little off my guard. An irregular heartbeat is an uncomfortable thing to experience; that pumping rhythm is there one’s entire life, and the body doesn’t react well when the tempo switches up. 

But what if there was no tempo? Enter science. NPR recently covered a story about an artificial heart that doesn’t act like a heart at all… at least in the traditional sense. In the past, artificial hearts like the Jarvik 7 were designed to mimic the natural processes of the originals – mainly, the electrically-stimulated 'pumping' action – and act as a total replacement for the damaged organs. In most cases, though, damage wasn’t severe enough to cause a total shutdown, and so a total heart replacement would actually do more harm than good.

...in some cases.

When this happened, a blood pump would be surgically attached to replace whichever hemisphere had failed. This pump did not have to regulate a heartbeat like the Jarvik would, since the rest of the organ was still there to do the job. However, the human body isn't exactly welcoming to such invasive procedures; though machinery is not ‘rejected’ in the sense that implanted organs are, there is still a chance of infection, making the process a bit risky (though worth it considering the alternative).

Yet the artificial heart designed by the Texas Heart Institute followed this same logic… just without the heart. Instead of one part of the heart being controlled by pumps, the whole heart is replaced. 

They work like a set of turbines, spinning in synchronization to circulate blood. There’s no pumping, no rhythm; there is no pulse to feel, just the constant whirr of machinery. By all accounts, anyone with this in their chest cavity is clinically dead. Yet the first human patient to receive this unique mechanism (it had already been tested on cows) did incredibly well. Though Craig Lewis, suffering from amyloidosis, died a month after receiving the implant, it wasn’t from his heart, but his failing liver.

Science often goes back to nature when seeking solutions to difficult questions; the story is no different when it comes to creating a man-made heart. But a living man without a pulse? After this experiment, it seems that nature might not always have the only answer.

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