Rachael, I did answer your PM but wanted to post here as well....Liver Shunt is not something only diagnosed in puppies. The specialist told me that often it happens that a pup can have a shunt that does not show up until they are adults ... they present with symptoms or with bladder stones.
If your vet suggests doing BAT's I would definitely do that.
Teddy Bear's thread:
http://www.yorkietalk.com/forums/sic...ver-shunt.html