IMHO, trying Coumadin prior to surgery would be a waste of time and not prove anything.
Again, IMHO, there are a lot of other factors that are more important in valve selection.
In my case, reducing the probability of repeat surgeries was the primary factor in selecting a mechanical valve. I got through my AVR with relative ease, but getting my sternum sawed open isn't necessary something I would look forward to doing again.
In eight years only I've had one complication from being on Coumadin and that was the result of a botched colonoscopy by a inept doctor, not caused by the Coumadin.
Alll the myths about Coumadin get a bit tiresome.
I shave with a razor, use hammers, saws, sharp knives, bust my knuckles working on my cars, crashed on my triathlon bike at 20mph, and have even had teeth pulled without any bleeding problems.
Is it just me or does it seem that the stories of the horrors of Coumadin seem come from people who aren't on it?
I would suspect that more folks stroke out from not taking their Coumadin than bleed to death from taking it.
Mark