What are the chances this man will survive?

My mother’s very close friend just suffered a double massive stroke and is currently on life support. The doctors said the next 48 hours will determine his fate. My mother doesn’t know any other details yet. I’m trying my best to keep her positive and in good spirits, but what are the odds of her friend actually recovering from this? Should we be preparing for the worst?

Edit: He is in his mid 40’s, and overweight. He had open heart surgery a couple years ago and has had heart issues for awhile.