Prayers for my grandpa

My Grandfather is back in the hospital.
He had a severe heart attack (his second) on Thanksgiving, followed by a period of dellusions (He thougth Hitler was visiting him ) and triple bypass surgery.
He's been home for a while though, and he's been doing great....driving, mild yardwork, etc.
Apparently, his doctors heard a flutter (?) in his heart and were going to have him come in tomorrow for a procedure to take care of it and do something with his pacemaker. But he was having trouble breathing and acting strange, so he was brought to the hospital by ambulance this morning at 5am.

I don't know how serious it is, since he was supposed to go in tomorrow anyway, but I'm a little worried about him....and could use some prayers and hugs for him.