I Have A Friend Who Had Her Heart Valve Replaced

I have a friend who had her heart valve replaced 3 years ago. She had an infection that spread to her brain and she had a stroke. She is 39. She has been in a medically induced coma for 11 days. She has endocarditis and has developed pneumonia. They are going to start a trac and feeding tube. There seems to be conflicting views on her recovery. How long can she stay in a coma and have a chance to wake up .... Somewhat normal?