It always hard to answer specific questions without all the details, like your brothers age and all his other medical issues. In general, his congestive heart failure and poor heart function put him at a much higher risk for a stroke and make it more difficult for him to recover from this stroke.
At our rehabilitation hospital we find that people with a low ejection fraction ( heart function) have a more difficult time participating in rehabilitation. When faced with two debilitating situations it is always good to dividewhat is going on into strengths and weaknesses. It is probably obvious what your brother cannot do, what you and the therapists need to do is identify those things he can do and build on his strengths. He may have to lead a much more sedentary life and the job is how to bring quality into that life.
Do you know if he will be able to return home? Are there people to care for him ar home? Will his home need to be modified? It is never too early to start planning. Ask to speak with the Case Manager at the hsopital.
Finally, be sure people do not give up on him and give him every opportunity to improve. Ask about whether he will go to a rehabilitation hospital. I wrote a series of blogs on WebMD under Chronic Conditions on How to Pick a Rehabilitation Hospital.http://blogs.webmd.com/chronic-conditions/2012/03/where-you-go-for-rehabilitation-makes-a-difference.html
Good Luck
After your stroke you may be experiencing a new normal, but remember what George Eliot said- It is never too late to be what you might have been. You still can achieve new goals.