When I asked my doc about minimally invasive procedures, he mirrored what Peter has said.
They did not believe there were notable differences for recovery, but more importantly, their philosophy is that the procedure is difficult enough in most cases that they do not want to be impeded by the sternum. Plus, if complications arise, they would have to waste precious time messing with the sternum and they do not like that.
I had thought of it not from a scarring standpoint, as this was my second AVR, but from a recovery perspective (anything to minimize discomfort is good). They said they also would not consider doing minimally invasive on a reop since the scar is already there.
For mitral and some other kinds of repair, they now can do a lot through truncates (spelling?). This is where they put a few little holes in the patient's chest and work between the ribs with their insturments and camera's. I believe Nancy's husband, Joe had this done.
The son of one of my business associates had mitral repair done in this manner. He went golfing less than one week after surgery.
Of course, he was 17 or some young precious age like that, so you can expect the kid could probably recover from even an open chest procedure twice as fast as most of us.
Don't worry about the minimally invasive procedure. They are not used that often and most of what seen suggests they add risk and hassle with no tangible benefit to the patient.
If he does in fact need an AVR, the surgeons will likely recommend a tissue valve for your father, since they don't usually like to use Coumadin (necessary with mechanical valves) with the elderly unless it's necessary. The tissue valves that are available today should ensure your father requires no further surgery (pending complications), so hopefully he won't have to endure another one later in life.
When I was in the hospital the first time, there was a nice old lady who was in her early '90's that had to have surgery. She got through it ok. The body can put up with a lot, even in our later years.
Kev