Fontan-Associated Anatomical Variants and Hepatic Fibrosis

Abstract

Objective: We hypothesized that a relationship between post-Fontan hepatic fibrosis and anatomical variants might exist. Methods: Attempting to limit confounding variables, we analyzed data from living, stable, post-extracardiac Fontan patients who underwent cardiac catheterization and transvenous hepatic biopsy procedures between March 2012 and June 2020. Results: We identified 120 patients who met the inclusion criteria. Of the 120, 35 (29%) had pulmonary artery stents. For the 35 with pulmonary artery stents, the average total fibrosis score was 3.2 ± 1.9 and the fibrosis progression rate was 0.36 ± 0.33, and for those with no pulmonary artery stents, the total fibrosis score was 2.6 ± 1.8 and the fibrosis progression rate was 0.27 ± 0.33 ( P = .13 and P = .11, respectively). Of the 120, 65 had functional univentricles of right ventricular type. Of these 65, 27 had pulmonary artery stents. For the 27 with pulmonary artery stents, the average total fibrosis score was 3.4 ± 1.8 and the average fibrosis progression rate was 0.39 ± 0.30, and for the 38 without pulmonary artery stents, the average fibrosis score was 2.3 ± 1.5 and the average fibrosis progression rate was 0.23 ± 0.21 ( P = .01 for comparison of both values). Conclusions: This study’s findings suggest that a post-extracardiac Fontan with a functional univentricle of right ventricular type plus a pulmonary artery stent may have more advanced liver pathology than those without a pulmonary artery stent at similar Fontan duration years and ages at liver biopsy.

Fontan‐associated liver disease and total cavopulmonary anatomical flow effectors

“…Our previous works and this current study have investigated the anatomic variables that may affect the rate and degree of hepatic fibrosis. [13][14][15][16] From such variables, we have attempted to construct a useful method for assisting with routine, long-term, post-Fontan follow-up.…”

“…1,2 Such effectors may include, but are not limited to, Fontan connection compliance, Fontan fenestrations and venovenous collaterals, disturbances at Fontan connection junctions, compliance of the large pulmonary arteries and vascular obstructions, pulmonary arterial microvascular cross-sectional area, pulmonary venous vascular compliance and obstructions, and functional univentricular diastolic performance. [13][14][15][16][26][27][28][29][30][31][32][33][34][35][36] In particular, a neonatal history of obstructed pulmonary blood, chiefly when accompanied by a functional univentricle of right-right ventricular type, appears to especially negatively affect the outcome of FALD. 14 In conclusion, in a relatively young, stable extracardiac Fontan patient cohort, average composite anatomical risk scores strongly correlated with average hepatic total fibrosis scores by anatomical group.…”

“…19,23 Transvenous liver biopsy added no significant time to the cardiac catheterization procedure. 16 Liver biopsy specimens were stained with hematoxylin and eosin, trichrome, and reticulin.…”

“…12 Patients were assigned to anatomical groups (with a minimum n ≥ 3) by functional univentricle type, presence or absence of venovenous collaterals and pulmonary artery stents, and neonatal history of obstructed or unobstructed pulmonary blood flow. Based on previous investigations, [13][14][15][16][26][27][28][29][30][31][32][33][34][35][36] we developed a composite anatomical risk score, which resulted in the best correlation with total fibrosis scores. We assigned 0 points for functional univentricles of either right and left ventricular type without venovenous collaterals or pulmonary artery stents.…”

“…This study builds on the findings from our previous reports that demonstrated hepatic fibrosis risk associated with a neonatal history of obstructed pulmonary blood flow and a functional univentricle of right ventricular type, presence of venovenous collaterals, and the presence of pulmonary artery stents. [13][14][15][16]…”