Differences in Prevalence and Severity of Liver Disease Between Lateral Tunnel and Extracardiac Conduit Fontan

Recent studies suggest differences in liver disease severity based on the type of total cavopulmonary connection (TCPC).

The purpose of this study was to compare the severity and progression of liver disease between patients with extracardiac conduit (ECC) vs lateral tunnel (LT) using 2 separate cohorts: i) TCPC at the initial Fontan operation (primary-TCPC cohort) and ii) Fontan conversion (FC) to TCPC (FC-TCPC cohort).

This is a retrospective study of adults with TCPC (ECC [N = 62, 46%]; LT [N = 73,54%). Liver disease severity was assessed at baseline using biomarkers (model for end-stage liver disease excluding international normalized ratio, Fibrosis-4 [FIB-4], aspartate aminotransferase to platelet ratio index [APRI]), and progression of liver disease was assessed as temporal change in biomarkers at 3, 5, and 7 years.

In the primary-TCPC cohort (ECC [N = 62,46%]; LT [N = 73,54%), patients with ECC had a higher prevalence of cirrhosis (27% vs 12%; P = 0.03) and worse disease severity at baseline (APRI 0.46 [0.34;0.61] vs 0.39 [0.29;0.52], P < 0.001; FIB-4 (0.89 [0.59;1.12] vs 0.76 [0.31;0.99], P = 0.009) compared to LT. Both groups had progression of liver disease (temporal increase in biomarker levels), but the ECC group had a greater temporal increase in biomarker levels resulting in a higher relative increase in model for end-stage liver disease excluding international normalized ratio, FIB-4, and APRI. There were no significant differences in prevalence and severity of liver disease at baseline, or liver disease progression during follow-up between patients with ECC vs LT in the FC-TCPC group.

ECC was associated with a higher prevalence and worse severity of liver disease at baseline, and greater disease progression during follow-up compared to those with LT. Further studies are required to determine the optimal strategies for the management of liver disease in patients with ECC.