title: Transient elastography may identify Fontan patients with unfavorable hemodynamics and advanced hepatic fibrosis.
abstract: BACKGROUND
  Transient elastography (TE) offers a noninvasive correlate with the degree of hepatic fibrosis. However, factors other than fibrosis affect liver stiffness. We sought to determine whether hepatic congestion related to hemodynamics in Fontan circulation influences liver stiffness measurement (LSM) assessed by TE.
  
  
  METHODS
  We studied 45 subjects with Fontan circulation undergoing cardiac catheterization with or without simultaneous liver biopsy. Subjects underwent TE within 5 days before catheterization. Clinical history, hemodynamic and biopsy data, and hepatic biomarkers were collected. Five subjects who had previously undergone liver biopsy and TE were also included.
  
  
  RESULTS
  Median age was 13.1 years (range 2.4-57.8); median time since Fontan was 9.9 years (range 0.1-32.5). No subject had known hepatitis C. Mean LSM for the entire cohort was 21.4 ± 10.8 kPa. Univariate regression analysis using LSM as a continuous outcome variable shows significant correlations with age (R = 0.35, P = .01), time since Fontan (R = 0.41, P = .003), Fontan pressure (R = 0.31, P = .04), cardiac index (R = 0.33, P = .03), pulmonary vascular resistance (R = 0.34, P = .03), systemic arterial oxygen saturation (R = 0.31, P = .04), and platelet count (R = 0.29, P = .05). On multiple regression analysis, Fontan pressure (β = 0.901, P = .03) and cardiac index (β = 2.703, P = .02) were significant predictors of LSM with overall model R(2) = 0.206. Univariate analysis shows LSM to be associated with more severe centrilobular fibrosis (P = .05).
  
  
  CONCLUSIONS
  Higher LSM is associated with unfavorable Fontan hemodynamics and advanced centrilobular hepatic fibrosis. TE may be a useful tool for identifying Fontan patients who warrant invasive testing.
authors.affiliation: Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, Mass, USA; Division of Cardiology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Mass, USA.
authors.forename: Fred M
authors.initials: FM
authors.lastname: Wu
authors.forename: Alexander R
authors.initials: AR
authors.lastname: Opotowsky
authors.forename: Roshan
authors.initials: R
authors.lastname: Raza
authors.forename: Sarah
authors.initials: S
authors.lastname: Harney
authors.forename: Chinweike
authors.initials: C
authors.lastname: Ukomadu
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Landzberg
authors.forename: Anne M
authors.initials: AM
authors.lastname: Valente
authors.forename: Roger E
authors.initials: RE
authors.lastname: Breitbart
authors.forename: Michael N
authors.initials: MN
authors.lastname: Singh
authors.forename: Kimberlee
authors.initials: K
authors.lastname: Gauvreau
authors.forename: Maureen M
authors.initials: MM
authors.lastname: Jonas
mesh_terms: D000293:Adolescent; D000328:Adult; D001706:Biopsy; D006328:Cardiac Catheterization; D002648:Child; D002675:Child, Preschool; D042241:Early Diagnosis; D054459:Elasticity Imaging Techniques; D005260:Female; D018729:Fontan Procedure / Q000009:adverse effects*; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D006439:Hemodynamics; D006801:Humans; D007223:Infant; D016014:Linear Models; D008099:Liver / Q000473:pathology*; D008103:Liver Cirrhosis / Q000150:complications / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
keywords: Congenital Heart Disease; Fontan; Transient Elastography