Our cat has had a heart murmur for about 10 years and it doesn't seem to have done him any harm. In that time he's lived alongside up to 5 dogs at once plus a brood of border collie pups - for at least a few years he decided to live outside and only come in for food occasionally and spent his time under a bush opposite the house come wind or snow. He also has asthma which is triggered by purring. He's 15 and still going strong!
Our cat has had a heart murmur for about 10 years and it doesn't seem to have done him any harm. In that time he's lived alongside up to 5 dogs at once plus a brood of border collie pups - for at least a few years he decided to live outside and only come in for food occasionally and spent his time under a bush opposite the house come wind or snow. He also has asthma which is triggered by purring. He's 15 and still going strong!