Dogs can suffer from the classic 'hole in the heart' - otherwise known as a ventricular septal defect (VSD) - seen in babies. The term describes a malformation of the heart where there is a hole between the left and right ventricles. The effect is not dissimilar to that caused by patent ductus arteriosus: a short circuit leading to a loss in the heart's ability to pump blood.
This illustration shows a ventral septal defect, or 'hole in the heart'.
A malformation of the heart leads to a hole between the left and right ventricles.
This causes blood to 'leak' between the two chambers, reducing the heart's ability to pump blood around the body.
Hole in the heart defects most frequently affect Terriers (especially Border Terriers and West Highland Whites), Springer Spaniels, Basset Hounds and Border Collies.
A dog with a 'hole in the heart', or VSD, may appear overly quiet and inactive. During any period of excitement, it may experience shortness of breath and or collapse, and its gums may appear tinged blue, due to a lack of oxygen. The symptoms of VSD will vary according to how large the defect is.
A small hole in the heart will sometimes seal of its own accord in the first year of life. Even if it remains open, a dog may well live with the condition for years without suffering any ill effects. Large defects will eventually give rise to symptoms of heart failure and require surgical repair.