Which condition is the most common cyanotic congenital heart disease in newborns?

Transposition of the great vessels is recognized as the most common cyanotic congenital heart disease in newborns. This condition occurs when the aorta and pulmonary artery are switched, resulting in two separate circulatory systems: one that circulates deoxygenated blood and another that circulates oxygenated blood. This arrangement leads to severe hypoxemia in newborns since oxygen-poor blood returns to the body without being re-oxygenated by the lungs.

In newborns with transposition of the great vessels, the presence of a patent ductus arteriosus (PDA) or atrial septal defect (ASD) often allows for some mixing of blood, which can temporarily stabilize the condition until corrective intervention can be performed. Immediate recognition and management are critical to improve outcomes.

While Tetralogy of Fallot is also a common cyanotic heart defect, it typically presents later in infancy rather than immediately at birth. Atrial septal defect and ventricular septal defect are acyanotic defects, often associated with left-to-right shunting, and usually do not cause immediate cyanosis in neonates. Therefore, transposition of the great vessels stands out as the condition primarily responsible for the acute presentation of cyanosis in newborns.