How is a ventricular septal defect (VSD) diagnosed?

Ventricular septal defect can be detected by cardiac auscultation; they typically cause systolic murmurs. Confirmation of findings from cardiac auscultation can be obtained with cardiac ultrasound (echocardiography - less invasive) and cardiac catheterization (more invasive).The heart can sometimes be seen or felt to be beating hard because of the extra work it is performing. Babies can be breathing fast or hard and have a fast heart rate.

An electrocardiogram can help determine the sizes of the chambers to see if there is strain on the heart due to the ventricular septal defect.

However, this can be normal at birth and change with time as congestive heart failure worsens. It can also suggest if there are other heart defects associated with the ventricular septal defect.

A chest X-ray can also help follow the progression of congestive heart failure by looking at the size of the heart and the amount of blood flow to the lungs. This may be normal at birth and change with time.

An echocardiogram may need to be performed for certain circumstances. If the diagnosis is unclear or if there is suspicion of associated anomalies, this test can help sort this out.

Most small ventricular septal defects will not require an echocardiogram as they tend to close, but often moderate or large ventricular septal defects will need to have at least one echocardiogram to provide the cardiologist a complete picture of the defect.

Although rare, in some children with ventricular septal defects a cardiac catheterization will need to be performed, particularly in the moderate-sized defects.

This can help the cardiologist determine more accurately how much blood flow is going out to the lungs. This can be very useful in determining the need for surgery in children who have had subtle signs of congestive heart failure but who do not have clear-cut evidence of the need for surgical repair.