My Husband Had Angiogram Which Showed Many Blockages. Some Up

My husband had angiogram which showed many blockages. Some up to 90 percent. He has quite an extensive medicated history. War fin bleed, perphieal vascular disease, 4 back surgeries,bladder cancer under control,terrible staff infection with last cervical surgery, Should he have open heart or stenting because he is so high risk. He is 77 yrs old. But still strong for his age. breathing tests are all good. No diabetes.,