I Had A Triple Bypass About 25 Years Ago And

I had a triple bypass about 25 years ago and I didn't seem to be having any problems. I noticed I was getting tired more often so I went in for a checkup. I failed a stress test and after an angiogram the doctor said that I only had one artery open and about 1/3 of my heart was working. He said it probably wouldn't do any good to have another bypass because my heart was probably damaged. Do I have any options to restore my heart to better condition?