Heart Valve Re-Operations

Hello,

I orginally asked a question regarding my 80 year old father requiring a 3rd aortic valve surgery.  I believe the doctor who answered my query thought I was talking about a CABG re-op, and therefore want to ask the question again as I am not certain his/her answer was relevant to my father's situation.

Again, my father, who is 80 years old and in NY Class II-III (50 mg of lasix/day and no issues w/ tiredness/breathlessness when walking or climbing a couple of flights of stairs), will probably be undergoing his 3rd AVR next month; his mitral may also be leaking as a result of the aortic valve.  His first op was in 1993 for an anureysm /avr; this was followed by another avr in 2002.  As I said, he is in relatively good shape (eats well/exercises).  Unfortunately, it looks as though it's either surgery or a gradual decline in health, and he would rather have surgery while he is still relatively strong.

My question is,  how much riskier it is for him to have this 2nd re-op in comparison to his 1st and second?  Is the scar tissue/age  a big obstacle for a surgeon?  At the Cleveland clinic, what is the mortality rate for someone my dad's age having a 2nd re-op and how does this compare to an 80 year old having his primary  AVR there?  Also, it it important for him to have a CAT scan along with a cath before the surgery?  Answers to these questions and any other advice you may provide will be greatly appreciated!

Thank you.