Our beloved golden passed away last week from a fatal arrhythmia. 2 yrs ago he was diagnosed with mitral valve disease, which seems to be pretty rare for goldens and he had been on six different medications since then. Both parents had OFA heart clearance, and I just don't understand how this could have occurred. Just a genetic anomaly? It makes me scared to get another puppy without understanding whether this could happen again or if I could find out in some way whether the puppy is susceptible.