Q.Hedge growth
Hedge is dead looking at the bottom and has large brown patches, is it still alive??
In parts it has had ivy crawling up it
Is there anything I can do to bring it back to life?

It looks to be a juniper hedge. If I'm correct, then I'm not optimistic about returning it to its former glory. Juniper does not break new stems on old wood that has stopped producing leaves. Trimming junipers (and many other hedge plants) with shears results in dense growth at the tip of branches which blocks sunlight to the interior. Without sunlight, those interior branches die. Creating some openings for light is crucial which means pruning, not just tip shearing