Hey sampson....i too have had MVP for years but have been very very lucky w. no symptoms and was told that MVP itself is not hereditary but one of the factors that figure into the 25% of the population that have it is our body types believe it or not. The general consensus of people who have it are those with a very specific chest type of alot of times is known as chicken breast, or people who have chests that are sunken a little or those with pronounced ribs cages that cover the heart area. I know it sounds strange but i swear i read it in the New England Journal of Medicine and read an article put out by the American Medical Association. I actually asked my heart doc about it and he said as a general rule it was true. You can bet when my daughters were born that was one of the first things i looked for and they didn't have it and have no probs. As far as virus and flu goes...most definately yes, yes, yes.....An increase in palps. are normal and if we don't get enough fluid into us and keep all of the organs hydrated its a well known fact that being dehydrated sets the series off. Plus not to mention your body is a little busy trying to fight off the bugs so i think not so much as it being an MVP problem as much as it being a palpatation thing. They say that 10 % of the population doesn't even know that they have mitral valve prolapse altho it is very common. I would just stay away from any over the counter drugs that have anything in them that ends with "phrene" and definately stay away from caffeine. I hope this helps a little....
My guess is yes, sickness may cause any type of heart rhythm problem to worsen in some people.
I have suffered from Mitral leakage (regurgitation) for years, and have atrial fibrillation (possibly for that reason). I have not noticed an correlation between sickness and heart rhythm problems - fortunately I rarely get a cold of flu, unfortunately I am right now.
In my case, I'm now 70, I ended up having the Mitral valve repaired, it no longer leaks, but the AFib continues.