Ventricular Septal Defect (VSD)

The wall between the two lower chambers of the heart is called the ventricular septum. An opening in this wall is known as a ventricular septal defect. A VSD causes oxygen-rich blood to leak from the left side of the heart, where the pressure is higher, to the right side. With large holes, this is a problem because too much blood flows to the lungs. This forces the heart to overwork and makes it get bigger. There are 4 types of VSDs, named according to where they occur in the septum: membranous defect, muscular defect, inlet defect, and outlet defect.

VSD accounts for about 20% of congenital heart defects. About five to 50 children out of 1,000 are born with this defect.

Ventricular Septal Defect
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A hole in the wall diVideoing the lower chambers of the heart results in oxygen-rich blood leaking into the right ventricle. This means that oxygenated blood is mixing with deoxygenated blood, and more blood is travelling to the lungs than is necessary.
What are the symptoms of ventricular septal defect?

The hole does not usually cause symptoms if it is small and does not allow much blood to pass through. For about 5% to 10% of cases, though, the hole may be large and cause congestive heart failure. A heart murmur may also be present.

These defects are usually identified when a doctor hears a heart murmur. A chest X-ray, electrocardiogram, and echocardiogram or, in rare cases, cardiac catheterization, may be done to diagnose this condition.

How is ventricular septal defect treated?

VSDs occur in a range of sizes and their treatment is very individual. Small holes may need no treatment and can sometimes close on their own. Larger holes will need to be closed in open heart surgery by applying a patch or sewing shut the hole. Sometimes, a closure device can be inserted through cardiac catheterization.

If there are several holes, the cardiologist may insert a band around the pulmonary artery, a procedure called pulmonary artery banding. This allows the baby to grow until the child is better prepared for surgery to close the holes.

What is the long-term outlook for children with ventricular septal defect?

The outlook for children with this defect is very good, particularly if the hole was small and easily repaired. Children in whom the hole was not repaired are at risk of infection, poor growth, and the development of Eisenmenger's syndrome. Today, this is rare.

Fraser Golding, MD, FRCPC