• Getty Images
    14 of 14
    Next: 12 Most Frequent Adult Dog Illnesses

    Certain congenital heart defects are often first noticed in puppies. Unless severe, many will be asymptomatic except for a murmur your veterinarian can hear when listening with a stethoscope. If severe, the puppy may grow slowly, fail to thrive, have difficulty breathing and have little energy. Surgery may be curative for some conditions.

    Many conditions, if treated early and appropriately, can be cured so that your puppy can live a long and healthy life.