My mytral valve prolaps was found in my early 20s. also under alot of stress. Found by echo cardio gram. An aunt and two cousins also have it. I have had to be pre-medicated with Antibiotics prior to dental or surgigal procedures ever since. No one ever suggested rechecking it again, however I have suddendly become allergic to the Antibiotics I have taken all my life. And now my Doctor has done a new echo to see if it "regergatates" don't have those results yet. If it does not, it may not be worth the risk of pre medicating. I was told that this condition is usallay hereditary, it can develope or in my case they think I was probably born with it. So I suggest an echo, and always exercise and reasonable weight.
Good Luck
Robin