Well we took Fiona to the cardiologist clinic at the Dixon show last weekend. The good news is that it's not a murmur! Thank god since she's only 10 months old. The cardiologist (who I guess is one of the best in our area) said that Fiona has what she calls a "prolonged first heart beat". Has anyone else heard of this? The way she described it is that a normal heart goes "dun-dun dun-dun" and Fiona's is more like "duuun-dun duuuun-dun". She said she's actually come accross this in other Cavaliers, and with many of them it doesnt turn into anything, and two years later it is either the same or has disappeared. She said it is nothing to worry about now, and to just have our vet listen for change. She was impressed that our vet heard anything at all, so she said that if the vet can hear that, there's no need to go to a cardiologist! Phew! It MIGHT be a sign of an eventual murmur, but most likely not for a while!