Answer

Thanks for the question Zena.

While I cannot diagnose this over the internet there is a strong possibility that this is related in some way to the heart problem. It does seem a little strange though that she was not displaying exercise intolerance while running and under stress which is what would normally happen with cardiomegaly { enlarged heart }. Cardiomegaly is normally a disease of older dogs, in a young dog like yours there is a possibility you are dealing with some form of congenital heart abnormality.

If she was resting or dozing when the incident happened there is a chance that she was experiencing a minor fit of some kind, it would be normal for a dog with inherited epilepsy to have its first fit in your dog's age group.

All you can do in the meantime is to keep her quiet and calm until she gets her heart workover. If any more incidents happen you should note down what the dog was doing at the time and any other details as this may well help your vet.

If I can advise you further please get back in touch.

Scott Nimmo BVMS