Low Albumin and Elevated FIB-4 Are Associated With Adverse Outcomes After the Fontan Procedure

Fontan-associated liver disease contributes to long-term morbidity and mortality. This study evaluated whether non-invasive liver fibrosis scores-aspartate transaminase to platelet ratio index (APRI) and fibrosis-4 (FIB-4) and routine clinical hepatic synthetic function, specifically albumin-predict adverse outcomes when obtained 10 and 20 years after the Fontan procedure.

We conducted a retrospective analysis of Fontan patients with laboratory data available at ≥10 years post-procedure. The primary adverse outcomes included death, heart transplantation, or Fontan failure. Failing Fontan physiology was defined as heart failure, poorly controlled ascites, plastic bronchitis, or treatment-resistant protein-losing enteropathy. Cox regression was used to evaluate associations between APRI, FIB-4, and albumin level with adverse outcomes.

Outcomes of 98 patients surviving at 10 years (but <20 years), and 109 different patients surviving at 20 years were included. At least one adverse outcome occurred in 8% (8/98) of patients at 10 years and 12% (13/109) of patients at 20 years. Albumin <3.5 g/dL was associated with adverse outcomes at both 10 years (hazard ratio [HR] 8.54; p=0.02) and 20 years (HR 4.31; p=0.03). FIB-4 >1.45 but not APRI was significantly associated with adverse outcomes (HR 21.3; p=0.03) at 20 years.

Low albumin and elevated FIB-4 scores, usually leveraged in evaluation of liver disease, are associated with more frequent adverse outcomes of death, heart transplantation, or Fontan failure. These markers may serve as simple, non-invasive prognostic tools in long-term follow-up.