It seems that the quest to build an artificial heart, which has been going on for around fifty years, has largely failed. It has not proved possible to build an artificial heart which you can pop into someone's chest and then forget about it. There have been lots of attempts, but the recipient does not usually last very long, in the absence of a transplant. The only device which has been approved for general use is that at reference 1, a device which includes an external box of tricks and which is approved as a bridge to transplant. It seems that clots are a major problem, and if not the clots themselves, the side effects of dealing with them. While I wonder about how an artificial heart compensates for not being wired into the control functions usually exercised by the brain.
Heart assist devices - left ventricular assist devices or LVAD's - have been rather more successful, devices which get put into the chest cavity to run alongside the heart, to provide a bit of extra power. Devices which are also mainly intended to be used as a bridge to transplant. Perhaps they can piggy back, from a control point of view, on the activity of the real heart?
While heart transplants seem to have moved on a long way from the heroic days of my youth, with Dr. Christiaan Barnard and his dentist patient, with reference 2 suggesting that they have become almost routine. That the control problem has been solved.
Bing does not deliver much which helps on this occasion, so I have very little idea how the device at reference 1 actually works. Perhaps once one moves into realm of things which can be sold, open science evaporates.
But a cautionary tale: technology has not yet solved all the problems, not even the ones which are superficially mechanical.
PS: the article also tells of lots of serious medical controversy and politics in this area.
Reference 1: https://syncardia.com/.
Reference 2: https://www.bhf.org.uk/informationsupport/treatments/heart-transplant.
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