Vascular dementia and violence... [View all]

Anyone familiar with this disease?
My 83 year old wonderful, intelligent brother waited too long to get his heart valve replaced (taking care of his wife with Alzheimer's) and now he is in very poor shape indeed as the blood flow to his brain was so poor before the emergency valve surgery.
The two of them live in a residential facility and, actually, she is doing better - being social, going out for car rides, etc while he has become quite violent and is striking out at the staff, punching people, yelling out the window, etc.
He is on a blood thinner and has begun an anti seizure med this week, Depakote,
I assume he is striking out at people as he is afraid and confused.
Anyone familiar with this situation?
Its horrible for his grown kids to watch as he was always the loving and smart dad they so looked up to....
Thanks for any advice