I just noticed Claire's post, but here's what I wrote anyway
The dialogue goes:
1: 気づかなかった
2: 気づかなかったって?どういういみ?
Like I said in the post I linked you to, a lot of the time「って」is used to infer common phrases, so it's all about making an informed guess as to what that phrase is. In this case, B is simply repeating what A said, so it could be「って言った?」or a broken up 「って言うのはどういういみ?」.
I'm pretty sure the phrase「っていうか」can be used in this way, but I can't find an explanation anywhere
You see it more commonly starting a sentence, to infer the quote rather than the other way around, and in structures like 'rather than <quote>, <clause>'. Maybe somebody else can clarify? I never know how to translate this properly a lot of the time.
EDIT: reading it again, Claire's explanation seems a lot better. I just wanted some help with「っていうか」