My dad was 66 and had a tissue valve replacement in 1981 and later in 2001 he got another valve replacement with Mechanical. He was a surgeon and lived a very active life. He was also on Warfarin after his second surgery. Last December, he had sore throat for three weeks and one day he vomitted and in like 15 mintues he passed away. I am not surre if his tissue valve failed or something else.