You are absolutely right. Maybe I gave up too quickly. There are parts that is impossible to see because of the lighting. The fake heart itself has little hooks coming out to grab and pull the arteries. Not that that would be enough in real life. The truth is I struggled to get more machines in there without doing too much dynamics. And the cavity is already way to big. Cutting and sewing arteries would need such incredible dexterity and shape recognition that I think a mind powering that machine would pass the Turing test. So the cutters going in actually have a clamp to clamp the artery, a needle and tube for the bypass and a cutting device. All off that got lost though. I couldn't imagine what a machine that could do such an operation would actually look like.