All good questions.
I've had three angioplasties in the past and a triple bypass 13 years ago. You go in scared because all of a sudden you're facing a life or death situation. Today's surgical successes are very good, but there is still risk with this type surgery.
1 Look on internet for coronary artery bypass surgery. It can get complicated but should give you a pretty good idea about the surgical procedure.
2. It's good that your brother is a non-smoker and maintains a fairly active lifestyle. Exercise is a good way to reduce the risk of coronary artery disease. Elevated colesteral levels. plaque in the blood stream, blood pressure, stress and heredity all can impact the risk of heart disease.
3. Cerrtainly it can be hereditary. My mom had high blood pressure. It was so high that a heart valve ripped. When it did, her blood pressure dropped to near normal and she lived another 10 years. I had a brother with igh blood pressure who died at 43 from a sudden caronary infarction.
4. At your age you should go to your doctor and get a thorough physical examination. You'll want EKG, EEG, thalium stress test, blood work, enhanced x-rays of heart and lungs.
I hope all goes well with your brother's surgery. He'll have some discomfort. They're going to want him to cough and that's going to hurt a lot where they split his chest apart. Follow yiour cardiologist's instructions. He should get into a monitored exercise program as quickly as he is physically up to it and push to meet their expectations. Watch diet.
Will be offering a prayer that all goes well with your brother.