Querying the same agent

This is sort of an etiquette question--a little more than two years ago I sent a query to an agent who requested the manuscript and then ultimately rejected it. Since then I have completely rewritten the book--it's the same basic story but it's told from the POV of a different character, so it's not like it was just a minor edit or even an additional draft, it's a completely new book.

I'd like to query her again but I'm unsure how to do it since she did read the first incarnation of the manuscript. Do I just query her as if we've never had any contact before or do I mention that she read the first version of the story and this is a completely rewritten book? Or do I just avoid querying her altogether? It was long enough ago that I feel like the storyline may ring a bell but she won't necessarily remember much about me or my work.

Thanks for any advice.

Thank you! That's exactly the information I was looking for. Much appreciated.