The

Fontan procedure is a palliative surgical strategy used in the

management of severe congenital heart defects, resulting in the

creation of a single-ventricle circulation. In this

physiological configuration, venous blood from the systemic

circulation flows directly into the pulmonary arteries, bypassing the

heart muscle. The operation is typically performed in early

childhood and significantly improves long-term prognosis, enabling

survival into the third decade of life and beyond. Over time,

however, children and young adults develop complications related to

the altered circulatory system, including chronic liver disease

predominantly driven by passive hepatic congestion. This condition

leads to progressive hepatic fibrosis, cirrhosis, and, in

a substantial proportion of patients, hepatocellular carcinoma.

Consequently, lifelong interdisciplinary specialist care, including

structured hepatological follow-up, is required from early childhood.

Progressive liver disease in children with altered cardiovascular

physiology poses distinct diagnostic and therapeutic challenges.