Subvalvular aortic stenosis is the form of canine heart disease which is most common in the Newfoundland dog. It is an obstruction which causes a rushing noise in the blood as it passes through the valve. It manifests itself as a heart murmur.
Although parents should have heart scans before breeding it is not easily detectable and can show up in later generations. The parents may not necessarily have the disease, but can still be carriers.
Regular checks of a puppy are essential to detect any sign of heart murmur, as the murmurs can come and go and may not always be detectable. The puppy can appear absolutely normal in every other way.
X-rays and cardiograms are necessary to detect the condition, which can be controlled with drugs for the dog's lifetime, though it can never be completely cured.
Symptoms of heart failure include sudden lethargy, continuous heavy panting and a rise in temperature
Surgery has proved ineffective in dogs, unlike humans who have a good recovery rate.
The outcome of this disease is bleak, resulting in early cardiac arrest and sudden death.
You would treat a dog with canine heart disease the same as a human with a weak heart - gentle exercise, plenty of rest, and a careful watch on the dog's weight. He will not be able to run and play like any other dog, but he does not know that so it is up to us humans to provide him with the right care.
This disease is more likely to occur in certain breeds, but the Newfoundland dog has the highest incidence among giant dogs. It is essential that your puppy's parents have no sign of this condition in themselves and in their history.