Tests and diagnosis

By Mayo Clinic Staff

Ventricular septal defects often cause a heart murmur that your doctor can hear using a stethoscope. If your doctor hears a heart murmur or finds other signs or symptoms of a heart defect, he or she may request one or more of these tests:

  • Chest X-ray. An X-ray image helps the doctor view the heart and lungs. An X-ray may identify conditions other than a heart defect that may explain symptoms.
  • Electrocardiogram (ECG). This test records the electrical activity of the heart through electrodes attached to the skin. This test helps diagnose heart defects or rhythm problems.
  • Echocardiogram. An echocardiogram uses sound waves to produce a video image of the heart. This image can help doctors see if you have a ventricular septal defect and if the heart is pumping properly. Echocardiography can also be done while a baby is still in the womb (fetal echocardiography).
  • Cardiac catheterization. In this test, a thin, flexible tube (catheter) is inserted into a blood vessel at the groin or arm and guided through the blood vessels into the heart. Through catheterization, doctors can diagnose congenital heart defects and test the strength of the ventricles — the heart's pumping chambers — and the function of the heart valves.
  • Pulse oximetry. This painless test measures how well oxygen is reaching tissues. It helps determine whether oxygenated blood is mixing with deoxygenated blood, which can help diagnose the type of heart defect present. A small finger clip on the fingertip measures the amount of oxygen in the blood.
Oct. 26, 2011