[{quoted}](name=Kyoki Shinkuro,realm=EUW,application-id=6kFXY1kR,discussion-id=9MJXEG8B,comment-id=0000000000000000,timestamp=2016-12-08T02:01:16.694+0000)
If you read Camille's color text and biography, it actually makes note of clockwork hearts. Camille has one and been alive for 80 yrs because of it. I am pretty sure that is long before the story of Orianna came to be.
Unfortunately, only 2 people knew how to make it: Hakim and his nephew. Hakim disappeared and died off a while ago. His nephew reappeared, lost all of his designs, and now works for Clan Medarda.
Which means, only 3 people know how now. Hakim, nephew, and Orianna. What makes the heart difficult is that the pervasion of magic, and the central component which makes up most technology (hex crystals and magic) is what prevents a heart pump that could be placed inside. Why would they have that when everything could be made in a vastly different way? It skews how things work.
I can only assume that her brain works like a computer now. What makes it hard to replace the brain for us is that we don't have a way to fully keep one's personality or reimbue their previous memories. You see in Orianna's lore that her personality slowly changed. She thinks more like a computer now, so what was magical and phantasmal (the ballet and theatre) have now been analyzed thoroughly for flow of movement. Her memories were probably downloaded as well as transferred through a crystal of some sort which powers her mind.
But yeah. In essence, he just put random hard drive in there and put in an Orianna OS with memories downloaded.
I can only assume that a mechanical heart for a fully living creature is a rather...esoteric thing to work out.