Varus's Q goes through Nocturne's shield

Well that doesn't make much sense at all. Last game against a Varus as Nocturne. Use my W against his Q. Goes right through and kills me. Last I checked, that was an ability and my shield negates that(mostly). Varus's Q is an ability. Since Nocturne just recently got a buff, I wouldn't be surprised that his W got messed up a bit.