If GoreTex lasts a lifetime, it can't grow with the heart. I'm guessing it is temporary while the skin forms a new pericardium (but then, what do I know?).
Also, imagine the technological advances during his lifetime. I am amazed to see what's happened in medicine in my own lifetime. What may have killed our grandparents is solved with a quick doctor's visit and shot. We've come to take so much for granted and now think we should live forever!
God bless the doctors, and the scientists who labor quietly for years/decades developing this stuff. Everyone knows who Terrell Owens is, but does anyone know who developed Gore-tex ? Not that we're a society that has its priorities out of whack, or anything ;)