In The Tell Tale Heart a moment of foreshadowing is when the narrator thinks he hears the old man's heart and the anticipation is building up.
In The Tell Tale Heart the narrator is battling his "disease". He copes by killing the old man whose eye was bothering him. He then thought he heard the old man's heart underneath im when it was his own.
In The Tell Tale Heart the narrator describes his hatred for the old man's eye. It was a pale blue with a film over it. It looked like a vulture's eye.