This question can't be really answered correctly. There really isn't any answer to it. Everyone and everyone's situation is completely different.
Plus, there is a lot to consider.
Have you EVER heard of someone dying because of a Triple Bypass?
People of all ages can have this surgery, but the biggest percent are really old.
People that have this surgery may have NO other heath issues, but the biggest percent of them have many other health issues.
People that have this surgery also may or may not live a healthy life, many may over eat, eat unhealthy food, not exercise, and not take perscribed medications.
Theres a lot of talk about "how long a bypass will last", but you never really hear of someone dying because their bypass failed after 20 years. And there are some people that had a bypass, and years later had more bypasses and lived many years later. They may say that a big majority of Triple Bypass people are only expected to live 10 years after, but thats because the biggest percent of them are over 70yrs old and they die of old age or some other health problem with-in 10 years after. There is many healthy people that have had a triple bypass that have lived many many years after, over 40 years after before dying of something else. Heart Surgery may sound very scary, but it's a great life saver.
Most people die of a heart attack or heart failure, they don't live to get the hospital to get treatment, they didn't even know they had any heart trouble.
Having a Triple Bypass means you made it, you have a second chance at life and your not going to be one of the millions that just have a heart attack and die with-out getting treated.