How is tetralogy of Fallot diagnosed?
The physician may have heard a heart murmur during a physical examination, and referred your child to a pediatric cardiologist for a diagnosis. A heart murmur is simply a noise, heard with a stethoscope, caused by the turbulence of blood flowing through the obstruction from the right ventricle to the pulmonary artery. Symptoms your child exhibits will also help
with the diagnosis.
When a newborn baby with significant cyanosis is first seen, they are often placed in supplemental oxygen. The increased oxygen improves the child's oxygen levels in cases of lung disease, but breathing extra oxygen will have little effect on the oxygen levels of a child with tetralogy of Fallot.
Failure to respond to this "hyperoxia test" is often the first clue to suspect a cyanotic cardiac defect. Infants with tetralogy of Fallot can have normal oxygen levels if the pulmonary stenosis is mild (referred to as "pink" tetralogy of Fallot). In these children, the first clue to suggest a cardiac defect is detection of a loud murmur when the infant is examined. Once congenital heart disease is suspected, echocardiography can rapidly and accurately demonstrate the four related defects characteristic of tetralogy of Fallot.
Cardiac catheterization is occasionally required to evaluate the size and distribution of the pulmonary arteries and to clarify the branching patterns of the coronary arteries. Catheterization can also demonstrate whether patients have pulmonary blood flow supplied by an abnormal blood vessel from the aorta (aortopulmonary collateral). |
