Suggest Prognosis For Present Health Conditions

My husband had acute pancreatitis with an infection, and respiritatory acidosis..He is on life support. His echocardiogram shows function at 15percent, I was told that could improve and recover to 65 percent where he was before or to a higher percentage. But I just had a nurse tell me that once it s down to 15 it will never improve...Who s right? His nutrition through the nose tube is at 75 and he is doing well there. His kidneys are putting out a lot of fluid, and am told that is great. His blood pressure is going very high during the weaning off oxygen tests. 5 tests so far, today he made it to 1hr 45 min before his blood pressure when dangerously high. Can he recover heart function....?