purchase of purebread dog

i purchased a puppy from a breader under the promise that the puppy was healthy and vet checked. when we took him for his (what was supposed to be 2nd vet visit) he was diagnosed with a heart murmur. he will not live long unless he undergoes surgery. i got in touch with the breeder who sold me the dog and found out that none of the pups where vet checked! i would like to know if their is any laws and what they are, on breeding and sale of purebread dogs and what kind of case (if any) do i have?

We can't offer help if we don't know where you are (see the instructions in red at the top of the screen?).

But, in a general answer...
If there was a written agreement (or even a much harder to enforce, verbal agreement) that the dog would be 'vet examined' and wasn't, then you probably have an action for breach of contract. I would suggest that you send a WRITTEN notice to the breeder furnishing the details, dates and support of your agreement that a 'vet examination' was included. Send it Certified RRR. Give them a few (7?) days to respond and if they don't, you might need to consider taking Small Claims court action against them.