Paddy has just had a murmur (graded at 2 on a scale of 1 to 6) diagnosed at age 4. I was told not to worry.
As someone else has posted, you can't hear an irregular heartbeat - it's a whooshing sound in the middle of the beat - so instead of "da-dum, da-dum, da-dum" you can hear a faint "da-whoosh-dum, da-whoosh-dum". Vet told me what to listen for and gave me the stethoscope to listen to it. I've lain on sofa with Paddy wrapped up on my and put my ear to his chest and can just hear it. It's the valve not closing properly, I think, and that's what the "whoosh" is mid-beat.
HTH.
Denise
