Stem cells are very important! They are in the beginning stages of life. They can differentiate into any type of cell. They come from babies, like fetuses, for the most part because people are cruel, but you can find them in a grown being too. In adults, stem cells repair damaged tissues and other things. Bone marrow transplants are a form of stem cell usage in order to treat a disease. fMarrow transplants can help to cure lukemia.
But my answer to the question is: I would just go for the bypass, unless I was given ALL the facts about stem cell therapy.
I hope that answers your question!