Evaluation of Fontan-associated Liver Disease and Ethnic Disparities in Long-term Survivors of the Fontan Procedure: A Population-based Study

Objectives: Fontan-associated liver disease (FALD) has emerged as a nearly universal chronic comorbidity in patients with univentricular congenital heart disease who undergo the Fontan procedure. There is a paucity of data reporting long-term outcomes and the impact of FALD in this population. Methods: Patients who underwent the Fontan procedure between 1992 and 2018 were identified using California registry data. Presumed FALD was assessed by a composite of liver disease codes. Primary outcomes were mortality and transplant. Multivariable regression and survival analyses were performed. Results: Among 1436 patients post-Fontan, 75.9% studied were adults, with a median follow-up of 12.6 (8.4, 17.3) years. The population was 46.3% Hispanic. Overall survival at 20 years was >80%, but Hispanic patients had higher mortality risk compared with White patients [hazard ratio: 1.49 (1.09-2.03), P=0.012]. Only 225 patients (15.7%) had presumed FALD, although >54% of patients had liver disease by age 25. FALD was associated with later deaths [median: 9.6 (6.4-13.2) years post-Fontan] compared with patients who died without liver disease [4.1 (1.4-10.4) years, P=0.02]. Patients with FALD who underwent combined heart liver transplant had 100% survival at 5 years, compared with only 70.7% of patients who underwent heart transplant alone. Conclusions: In this population-based analysis of long-term outcomes post-Fontan, Hispanic ethnicity was associated with increased all-cause mortality. Further, the prevalence of FALD is underrecognized, but our data confirms that its incidence increases with age. FALD is associated with late mortality but excellent posttransplant survival. This emphasizes the need for FALD-specific liver surveillance strategies in patients post-Fontan.