Not always straight forward. I was born with a heart murmur that has never affected me that I am aware. It seems mine only shows up when I am run down or Ill, at other times it has never shown up on tests etc anywayMy eldest Ridgeback was diagnosed with a heart murmur when he was a couple of years old, I was pretty devastated as part of choosing the breed was their endurance. I cant remember the reason for that visit, I'd seen no signs of anything up with him. I took the next few weeks carefully, but still there were no signs, so I took him out running, 6 - 8 miles 2 or 3 times a week, then in winter we would go out in the dark with my mountain bike and some serious lights. He was fine. When he was about 7 or 8 at another vets visit the different vet said there was no sign of a heart murmur. Was there ever one? Do vets just like to scare us? We'll never know, cancer took him 2 years ago at 11 years old.