Tricuspid atresia is a cyanotic congenital heart defect characterized by complete absence or agenesis of the tricuspid valve, resulting in no direct communication between the right atrium and right ventricle. This creates an obligatory right-to-left atrial shunt through an atrial septal defect (ASD) or patent foramen ovale (PFO), as all systemic venous return must cross to the left atrium to reach the systemic circulation. The right ventricle is hypoplastic (underdeveloped) because it receives no direct blood flow through the absent tricuspid valve. Pulmonary blood flow depends on alternative pathways: a ventricular septal defect (VSD) allowing blood to flow from the left ventricle to the hypoplastic right ventricle and then to the pulmonary artery, or a patent ductus arteriosus (PDA) providing aorta-to-pulmonary artery flow. In the most common classification (Type I, normally related great arteries with restrictive VSD), pulmonary blood flow is diminished, producing significant cyanosis. The mixing of oxygenated and deoxygenated blood in the left atrium results in systemic oxygen desaturation. Survival depends on maintaining these alternative pathways for pulmonary blood flow. Surgical palliation follows a staged approach: neonatal stage...