I don't speak english very well. I am new in the breed, I know TVD means Tricuspid valve dysplasia, but I don't what it is.
Please, can someone be gentle and take some of their time to explain a foreign what is Tricuspid valve dysplasia.
Thank you very much.

Here is a link to a good article - explained by a fellow Lab person. Even though it is in English, you should be able to look up any familiar terms without a problem.
http://www.labbies.com/tvd.htm