What is ventricular septal defect (VSD)?

If your dog is diagnosed with ventricular septal defect (VSD), it means that it has an opening in the division between its heart ventricles. VSD is a congenital disease in dogs and affected dogs should not be used for breeding. When a dog is diagnosed with ventricular septal defect defect, its parents should also not be used for breeding any longer. Siblings can be used for breeding, but only after careful physical examination. The offspring of such siblings should be carefully screened for VSD, and if the problem is diagnosed the parents should not longer be used for breeding.

As a dog embryo develops, the heart begins as a single tube. This tube will then gradually separate into four different chambers. Abnormalities can appear at several different steps in this intricate process and this can lead to ventricular septal defect in a dog. When a dog has a hole in the division between the heart ventricles, it will cause abnormal blood flow inside the heart. The exact symptoms will vary depending on size and location of the abnormality. 

Symptoms of ventricular septal defect in dogs

The nature and extent of the symptoms will depend on both the size of the abnormality and exactly where it is located. In mild cases of ventricular septal defect, most dogs will display no symptoms except heart murmur. It is even possible for a small defect to close on its own as the dog matures.

In a dog with a larger defect, the pressure in the left side of the heart will be higher than the pressure in the right side, and there will be a blood flow from left to right via the defect. The left side of the dog’s heart will be forced to work harder than normally and more blood will circulate to the lungs. This will in turn cause a higher than normal work load for the lungs. If your dog is suffering from ventricular septal defect, the symptoms can develop over the course of several months or even years. Common symptoms of ventricular septal defect in dogs are exercise intolerance and shortness of breath. In severe cases, abnormal heart rhythm can lead to premature death. If the heart develops a so called reverse stunt due to the uneven pressure in the heart, the result can be cyanosis, i.e. the pink mucous membranes of your dog will turn grey.

Ventricular septal defect treatment for dogs

To begin with, the various symptoms of heart disease can be treated to make the dog feel better. The veterinarian can administer medications that will support the heart and reduce any pulmonary congestion. This should normally be combined with a special diet suitable for dogs with ventricular septal defect and restrictions when it comes to exercising. If the dog is to undergo procedures such as dentistry, precautionary antibiotic treatment can be administered to lower the risk of infection.

In dogs where a major defect has been found in the heart, pulmonary artery banding is a surgical option that will decrease the blood flow across the abnormal area. This will make the overload on the lungs and the left heart much lower. Pulmonary artery banding is however only carried out before the development of right-to-left shunting. The other possible surgical treatment of ventricular septal defect in dogs is to repair the defect. This will however require open heart surgery, which is a very risky procedure even for otherwise healthy dog.

Cardiovascular and circulatory problems in dogs: (click for more info)
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Congestive heart failure in dogs
Degenerative mitral valve disease in dogs
Dilated cardiomyopathy in dogs
Heart valve dysplasia in dogs
Hemolytic anemia in dogs
Patent ductus arteriosus in dogs
Pericardial effusion in dogs
Pulmonary hypertension in dogs
Pulmonic stenosis in dogs
Thrombocytopenia in dogs
Ventricular septal defect in dogs
Atrial septal defect in dogs
Tetralogy of Fallot in dogs
Von Willebrand disease in dogs