Mitral Valve disease and breeding. - Page 1

I am dealing with a situation that I need to learn more about and hope folks here can advise or steer me in the right direction for accurate research. We have just gotten a male pup from a very reputable breeder. He arrived at 16 weeks, in good condition and happy as a lark. As is common sense, the pup was taken to the vet for a general check up a day or 2 after arrival. The vet heard a "click" when listening to the heart. The vet was then told the pup was bought as a possible breeding prospect to which the vet replied the pup should definitely not be used for breeding. (Let me state it was not a murmur, which we have experienced in young pups that were gone by puberty). 
Anyway, the pup was then taken to a cardio specialist to further determine what was going on and this vet stated pup was born with mitral valve slightly off (meaning not aligned properly) which is causing a tiny leak hence the "click" sound heard by the first vet. Cardio vet stated pup should have a follow up EKG in a year or so but that she didn't expect it to get worse and probably wouldn't be a huge concern overall. 
After some basic research on our part we found that another breed (the Cavalier King Charles) is rampant with this issue and that it is thought it could have been avoided had breeders not bred dogs known to have mitral valve issues. 
So here is my question for anyone who might know more on this subject. The breeder did have a clear health check prior to shipping the puppy, so we are not trying to get on their case, we just want to do best going forward. 
If this was your breeding would you check the parents out? According to the Cavalier folks, they want parents checked and shown to be clear as they feel it is totally hereditary in that breed (this pup is not a Cav, just the breed I found with the most info).  
I'm going to talk to the breeder in a few days and I want to discuss the breed overall, not just this pup. It is a breed with a VERY limited gene pool so it's not like I can find suitable males within even 500 miles so this puts a big wet blanket over our immediate plans. It took us 3 years to find this pup with diverse enough bloodlines to what we have here and to convince the breeder to send it to the USA, sigh.
Does anyone have any experience as to the genetics of this? Is it truly a genetic thing, or maybe a fluke? The internet is overrun with good and bad info so I'm not sure which to believe. 
Thanks all,
Annette
 

What you are describing is Mitral Valve Prolapse. I have actually researched quite a bit on this topic last week. MVP is nearly identical in humans and canines, it is thought to be genetic passed down in a pattern. It is also shown to be polygenic, with clear parents sometimes producing MVP. Both of my parents have had an Echo, and I can say without a doubt that I didn't inherit it from either of them. I was told it is benign in 95% of people and is medicated if discomfort becomes a problem, but meds are not necessary. Severe regurgitation (only seen on Echocardiogram) may make the dog lethargic, but this degree of regurgitation is not often seen. I was told that many many people are diagnosed every year, and it is very very common.

If the gene pool in your chosen breed is already limited w/ very few dogs, I don't know that I'd throw the baby out with the bath water so to speak.

Melissa
 

It can be genetic or congenital. I have it; neither of my parents have it. No one else in my family has it that we're aware of. 

With Cavaliers, it's degeneration that's the issue, not just the click heard when valves are slightly off. My one valve is just a bit longer, creating a slapping towel sort of noise that a doctor can hear...but only if I'm standing when they check it. I've had this since I was a kid, and it's never gotten worse. It was first heard 20+ years ago. When I was pregnant, it disappeared and it's disappeared several times before and after that. Sometimes an echo shows it, sometimes not. And sometimes they hear it, sometimes they don't. It's not degenerative; it's simply a valve that is slightly mis-aligned for whatever reason. Degeneration of a mitral valve is much more serious. Regurgitation and degeneration of the tissue itself is what leads to heart failure and thus the devastating consequences seen in the Cavaliers. Disease is different than simple prolapse...have him thoroughly evaluated and then go from there. Don't make any hasty decisions at this stage. 

Thanks so much for the info. I was getting pretty confused because a) both parents seem to be clear (talked to breeder and have never had an issue at any regular check up, but never did EKG or any other heart specific testing and b) as far as we know it's not a breed problem. I'm not planning on any hasty decisions, although both vets recommended neutering (a 16 week old pup! I DON'T THINK SO). Both parents have been bred prior although I don't think they'd been bred to each other prior to this litter. No heart issues with any of the progeny as of this point, but of course they've only had regular stethoscope checks since there is no reason to delve further. 
Strangely enough one of my best friend's husbands was just diagnosed with this so it is fresh in my head (humanwise) from that. I distinctly remember him saying his was congenital and that was pretty common (as opposed to genetic). 
The gene pool for the breed is very small so I was really hoping not to just dismiss this guy right off the bat, especially as he's such a great little guy with outstanding temperament and very good conformation. The temperament was the clincher, of course. 
Oh, and I'm not discussing Beaucerons here. As that is the breed in my avatar I didn't want to start some sort of rumor mill going just in case :D. 

Once again thanks for easing my mind. I'm going to go forward with registering him and letting him grow up for a while. We'll do a recheck in a year or so to see where things stand. I'm guessing if it degenerative then it may change along the way?

Annette
 

Mind sharing what breed this is, then, now that we know it's not the breed of your user name and avatar?