My Brother Is 79 And His Heart Is Functioning At

My brother is 79 and his heart is functioning at 20%. He is retaining fluid in his legs, lungs and mid-section. He is very weak. He had surgery in December, 2015 for patella after suffering a fall. He has 100% blockage in the left descending artery as well as in another artery which has formed its own by-pass. The doctor said he was in no condition to have surgery and they continue to increase his fluid meds and blood pressure. He has celiac disease and is very thin. What do you think. He will see the doctor in another month. He says he is trying to strengthen the heart and is this possible?