Well you have got to love that really. I would be thrilled to know that I would not have to take coumadin the rest of my life. As a tissue valve receiver, (had my surgery in December of 07) I love that I am at 100% recovery and do not depend on medication for my survival. Less than 10% sounds like good odds and I imagine that if they ever had to go back in again, they might be able to repair that without a full chest slice.