In a normal newborn, the free wall of the right ventricle is typically what thickness?

In a normal newborn, the thickness of the free wall of the right ventricle is typically within the range of 2-4 mm. This measurement reflects the developmental stage of the heart in neonates, where the myocardium is generally thinner than in older children and adults due to the lower demands on the right ventricle in terms of pressure.

The right ventricle is responsible for pumping deoxygenated blood to the lungs for oxygenation, and in a newborn, the circulatory dynamics are different compared to older individuals. The relatively thinner walls are a result of the heart adapting to the lower pressures it encounters during this early stage of life. As the child grows and the heart's workload increases, the myocardial thickness of the ventricles will generally increase to accommodate the greater demands of the circulatory system.

This understanding is crucial for cardiac sonographers as they assess heart structures and function in pediatric patients. Correctly identifying the typical thickness helps in diagnosing potential cardiac abnormalities or conditions in newborns.