How does assessment of pulmonary blood flow aid in the diagnosis of cyanotic disease?
The first consideration in diagnosing CHD is whether the infant is clinically cyanotic.
Cyanosis may be secondary to admixture of oxygenated and deoxygenated blood, which can appear as increased blood flow to the heart with enlargement of the pulmonary arteries, or may be secondary to blood shunted away from the lungs, which would appear as decreased blood flow with small to absent pulmonary arteries.
Assessment of blood flow includes looking for shunt vessels at the periphery of the lung fields or behind the liver shadow.
