Very unique and cool idea! And very cool adition to the razing genre.
I am not sure if the controls convince me. I like how the nanobot only moves in the direction youre pointing when theres a heartbeat but I would made it like it will be faster if you stay in the center of the vein; hurting the vessel seems like a bad think (I had to read the description to realize I was actually donig good making it bleed) and also, idk how it should be done but i find it pretty hard to collision with the plaques when thats the reason the nanobot is in the body in the first place, and it doesnt seem too punishing to not clear them.
On the overall, I love the idea and the mechanics a lot but I think it needs some more polishing and testing on how the mechanics work to make a really amazing game with this idea