No no no, he will have time, plenty of time :) Remember it will be gradual and he will likely feel the symptoms at around 90%. Also it is worth remembering that he could open collateral vessels which are natural bypass vessels on the surface of the heart.
Thanks for the response.Yes he is on aspirin daily. Well if the blockage does go 99% does he have enough time to have a stent or will it be too late? Does he not end up getting a stroke?
I assume your Father is on Aspirin each day? I wouldn't worry. First of all, the blockages will not jump from 70% to 100% over night. What he needs to do is take his daily aspirin and everything will be just fine. IF a blockage does worsen, say get to 99%, then he will feel symptoms and can then have a stent inserted. Aspirin helps prevent the blood from forming clots, so preventing a 100% blockage from very quickly forming. He is doing very well for his bypass :)