I have my brother in critical condition in hospital,he has sufferred a stroke on the left side of his body,he had heart attack at the same time,doctors say he has a blood clot in the head and a swelling, he goes on to say that part of his brain is dead,what is the cause of all this?he is also diabetic and has blood pressure,what are the chances of healing,he is now opening his eyes and i doubt he is seeing anything,please help.