In a newborn with tricuspid valve atresia, what would be the expected chest X-ray finding?

In a newborn with tricuspid valve atresia, the expected chest X-ray finding is decreased pulmonary markings. This condition leads to an underdeveloped right ventricle due to the absence of the tricuspid valve, ultimately resulting in reduced blood flow to the lungs. Since the blood flow is diminished, the pulmonary vasculature is less prominent on X-ray, which is reflected in the reduced vascular markings in the lungs.

In the context of tricuspid valve atresia, the central pulmonary arteries are often hypoplastic, further contributing to the appearance of decreased vascularity. Additionally, these patients typically present with some degree of hypoxemia and cyanosis due to inadequate pulmonary blood flow, which, coupled with the decreased pulmonary vascularity, manifest clearly on a chest X-ray.

While an enlarged cardiac silhouette could be seen in certain congenital heart diseases with volume overload situations, tricuspid valve atresia primarily causes an underdeveloped right heart structure that does not lead to heart enlargement on initial imaging. Normal lung fields would not typically be present in the context of cardiac issues associated with decreased pulmonary flow, and increased pulmonary vascularity would be inconsistent with the lack of blood flow to the lungs due to the structural anomaly.