Dog and cat enlarged heart is a symptom of different conditions. If you notice that your dog or cat seems to be wheezing or seems to be gasping for breath all the time, it may be because of a serious issue, like a heart condition.
More reading
Natural diuretics for dogs with congestive heart failure
Liquid meal replacement for cats
When your cat's heart is enlarged, it may only be temporary. This is the case when it happens during pregnancy. See a veterinarian to learn more about what's happening in your pet's case.