What if the device keeping your heart beating was entirely man-made? Inside a high-precision manufacturing facility in Singapore, trained mostly women operators sit behind microscopes, carefully stitching delicate heart-valve tissue by hand. A single valve can require around 1,000 stitches, with every movement demanding exceptional precision, judgement and months of training. For Jai Arora, who has lived with one of these bioprosthetic valve for five years, watching the process during a patient experience visit revealed a side of his lifesaving device he had never imagined that even in an age of automation, some of the most critical work still depends on the human hand.