Hello...age is not the barrier for Bypass surgery. Main factors to decide right modality of treatment for your grandfather are-
1.Heart function/EF on 2DEcho.
2.Number of blockages in heart/CAD.
3.Co-morbid conditions like
diabetes, asthama,
kidney disease etc. (Overall physical fitness needed for bypass surgery & it can be done with due risk)
Next Steps
Other methods for treating heart blockages or coronary heart disease incude -Medical management / Angioplasty.