My Husband Was Told His Heart Function Is Between 20

my husband was told his heart function is between 20 to 25% that he has no blockages that his heart muscle is not working possibly due to a virus from years ago the insurance will not allow a defibrillator for three months the doctor also said that it would not get better they put him on a water pill and heart medicine and that if his heart function went down to 18% he would be put on a heart transplant list he is 62 years old with no other medical conditions. The doctor told us this was significant I assumed this meant terminal since he said his heart muscle would not improve that they could get him some relief with the medications. He feels better dropping 15 pounds of weight with the water pill but he still has trouble breathing - his breathing was not bad enough for him to be on home oxygen per the insurance company. We have good insurance it TRI Care / Humana