Childhood Liver-Related Abnormalities After Fontan Completion: Evidence from a 20-Year Tertiary Centre Cohort.

Fontan-Associated Liver Disease (FALD) occurs due to increased venous pressures and reduced cardiac output that result following Fontan completion. This may eventually progress to fibrosis, cirrhosis and in some cases, hepatocellular carcinoma. There is currently no consensus regarding the age at which hepatic insult typically begins. Therefore, this study aimed to assess evidence of biochemical and ultrasound-based liver abnormalities to inform effective liver surveillance and follow-up protocols. We conducted a retrospective single-centre cohort study with serial cross-sectional analyses of 353 Fontan patients born between 2003 and 2022. Results from biochemical tests and ultrasound scans were used to assess post-Fontan liver function. Available paired comparisons between Liver tests (LTs) and platelets at pre-Fontan and at 5-, 10-, and 15-year post-Fontan were analysed, and abnormal values at each time point were recorded. Post-Fontan liver ultrasounds were also used to assess changes in liver structure. 82 liver ultrasounds (done at a median of 8 years post-Fontan) were available, with 59% exhibiting abnormal hepatic echotexture, and 3 cases of focal lesions. Pre-operative, 5-year, 10-year, and 15-year post-operative LTs were available in 155/353, 298/353, 166/353 and 51/353 patients, respectively. The proportions of abnormal LTs were 17%, 56%, 71% and 63%, respectively. Between pre-Fontan and 5 years post-Fontan, Bilirubin, ALT, and Platelets showed liver-related abnormal progressions. Biochemical and ultrasound data indicate that liver changes are detectable in childhood, but these findings should be interpreted cautiously due to incomplete data that preclude adequate longitudinal analysis. Current post-Fontan liver monitoring is limited, and our findings support the case for early structured liver surveillance in the paediatric population.