Can a bank/credit union etc revoke a Heloc if market turns?

[Seth Rouch]

Hi all, I’m curious to know if: I have a HELOC, for easy numbers let’s say $100k, then the market turns/tanks. That equity is no longer real essentially. Would/coukd the HELOC be “revised” or “revoked” if I’ve not used/pulled any funds out? Could the amount be changed if I have pulled nothing out? Secondly: I don’t believe this to be the case but wanted to check- Would/could the note balance be called due in a tanking economy? (Assuming no foreclosure happened)