Hi,
Thanks for query,
It seems that there is infection at the site of belly button pierced.
Go for antibiotic course,anti inflammatory medicine.
Do daily dressing with antibiotic cream.
As she is having MVP,be careful and take this problem seriously.
Avoid taking bath in sea water.
ok and bye.

The need for antibiotic before such a procedure would depend on the presence or absence of mitral regurgitation due to MVP. If there is no leakage, there is usually no need for antibiotic prophylaxis. However, if she has been advised antibiotics before dental procedures, it is probable that there is some degree of mitral regurgitation. Belly button piercing, if done with all aseptic precautions by qualified personnel, is harmless. However, the caution advised by most doctors is due to the fear of infection which can spread to the mitral valve (prone to infective endocarditis, due to MVP). Such infection of the valve is called infective endocarditis and can be quite serious. In addition to the problem of prolonged infection needing hospitalization and long-term antibiotics (4-8weeks), there is the danger of the leakage from the valve increasing, need for emergency valve replacement, etc.
Even though, in terms of absolute risk, the chances of such complications are not high, yet the very grave nature of the many complications that could occur necessitates prudence and caution........