Have faith in the docs . My mom had 4 heartattcks , due to her diabetes she had 2 of the sururies where they clear the plaque out.(sorry don't remember the name ) They told her she couldn't have bypass as the bottom part of the heart was dead. So she took it easy , she also developed n ulcer on a foot . after a while she just sat ending up in a wheel chair. For 5 years then they discovered she had enough blood flow through the out side veins they could do by pass. that was 8 years ago, she started 2 years ago doing the arthritics water classes she now teachers them and walks with out even a cane.
Many things are happening in the medical feilds, not to long ago my diabetes would have been a death sentence, now people are living almost normal lives. I know I do.
I'm sending you a big hug I know its hard to be strong but your dad needs you to be . Always remeber too that humer ,laughter,and positve emotins really help with healing. I've seen that in my mom heart stuff and my hubbys cancer. If you need to talk just e-mail me. I care.