Posted: 17/03/2014 at 16:16
Without seeing a picture it's a bit difficult to tell! Sorry! However, if it's been there for quite a while, the chances are that the roots are well-established so don't give up yet.
I have two wisterias along the front of my house - very long established - and last year I had to prune some of the branches very severely, to the point where there was just nothing left on parts of them. The main parts (just above ground) are really big - about ten or eleven inches in circumference, so their overall size - and what was left untouched - may well have contributed to the fact that where I'd cut stuff off did produce more shoots as the summer progressed.
One way to establish whether there's still hope might be to take a sharp knife and slice/scrape a bit through a bit of the bark of what you have left. You'd probably be able to see then whether it looks "white-ish" or definitely dead. It won't look particularly green beneath the surface, but I think if it's definitely dead you'd probably be able to tell.