Ventricular Septal Defect (VSD)

This is a hole between the two pumping chambers (ventricles). It allows some oxygenated blood to pass from the left side back into the right side and through the lungs. The amount of abnormal blood flow depends on the size and site of the hole as well as the pressure difference between the two sides of the heart.

The abnormal flow produces the murmurs that are heard, and also the thrill, a vibration, which can be sometimes felt.

If the hole is small, the child is well and there are no problems. If the hole is moderate, the extra blood in the lungs makes them heavy and the child may breathe quickly, be slow to feed with poor weight gain, and have increased chest infections. These complaints are more marked if the hole is large.

The children with medium or large holes require medications, those with small ones do not. Echocardiography can show where it is, how big it is and often give an indication of whether it will close by itself.

Most holes will close spontaneously or get significantly smaller. Some will not and will require operation. The usual indications for operation are:

  • Failure to thrive adequately, despite medication in the first year of life.
  • The worry about high blood pressure in the lung arteries.
  • The persistence of a large blood flow into the lungs at over 7 years of age.
  • Development of a leaking aortic valve related to the hole.
  • Development of extra muscle in the right ventricle secondary to the abnormal blood flow.

The operation to close the hole, usually with a patch, is performed using the heart lung machine (cardiopulmonary bypass). Occasionally in small babies, or in those where there are additional significant problems, the blood flow to the lungs may be reduced by a preliminary operation – a banding, that narrows the lung artery.

Antibiotic prophylaxis is required, probably for one year after the spontaneous closure of the hole. If the hole is closed surgically, and if there is no murmur and no residual leak, endocarditis prophylaxis can be stopped after one year. If there is a residual murmur from a leak, or signs of leakage, antibiotics should be continued until these resolve.


Victoria & Tasmania