Welcome to Healing Well! I'm not a regular member of this forum, but am helping out while a friend is away. I happen to have mitral valve prolape myself, but once it was diagnosed, and I knew it was okay, it didn't bother me any more.
I found a site that discusses the surgery, in case you're interested:my.clevelandclinic.org/heart/disorders/valve/mvrepair.aspx?authoringerror=noupdatesongetrequest#advantages
I know that certain things trigger my problem--caffeine, wine. and stress are three.
Here's another interesting site:www.heart-valve-surgery.com/mitral-valve-prolapse-symptoms.php
Hopefully someone will be by to share more information soon.
Good luck to your friend. He/she is lucky to have you.