title: Evidence of endothelial dysfunction in patients with functionally univentricular physiology before completion of the Fontan operation.
abstract: BACKGROUND
  Postoperative thrombosis after a cavopulmonary connection has been widely described. Abnormalities in coagulation seem to occur early in the course of patients with functionally univentricular physiology, and may precede surgery. Endothelial abnormalities due to chronic hypoxia, and hyperviscosity, may contribute to this scene. The purpose of our study was to investigate if patients with a superior cavopulmonary connection have altered levels of endothelial and coagulative markers in the plasma.
  
  
  METHODS
  We compared findings in 10 patients, aged from 4 to 19 years, with 6 age-matched normal controls. We measured levels of von Willebrand factor antigen, thrombomodulin, tissue-type plasminogen activator, plasminogen activator inhibitor-1 and d-dimer in the plasma using enzyme-linked immunosorbent assay.
  
  
  RESULTS
  We found increased levels of von Willebrand factor antigen (p = 0.01), tissue-type plasminogen activator (p = 0.01), and decreased levels of thrombomodulin (p = 0.008) in the patients when compared to controls, while levels of plasminogen activator inhibitor-1 were not different. Values of d-dimer were within the reference range. Levels of tissue-type plasminogen activator had a positive correlation with von Willebrand factor antigen (r = 0.66, p = 0.008).
  
  
  CONCLUSIONS
  Altered levels of endothelial markers in the plasma, in the presence of normal levels of d-dimer, suggest that endothelial dysfunction may precede the occurrence of intravascular coagulation and thrombosis in patients with functionally univentricular physiology. These observations may have therapeutical implications.
authors.affiliation: Department of Paediatric Cardiology and Adult Congenital Heart Disease, Heart Institute, University of São Paulo Medical School, São Paulo, Brazil. conangelica@incor.usp.br
authors.forename: Maria A
authors.initials: MA
authors.lastname: Binotto
authors.forename: Nair Y
authors.initials: NY
authors.lastname: Maeda
authors.forename: Antonio A
authors.initials: AA
authors.lastname: Lopes
mesh_terms: D000293:Adolescent; D000328:Adult; D000941:Antigens / Q000097:blood; D002648:Child; D002675:Child, Preschool; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D018729:Fontan Procedure; D006352:Heart Ventricles / Q000002:abnormalities*; D006801:Humans; D008297:Male; D017395:Plasminogen Activator Inhibitor 1 / Q000097:blood; D018180:Thrombomodulin / Q000097:blood; D014841:von Willebrand Factor / Q000276:immunology
chemical_list: D000941:Antigens; D017395:Plasminogen Activator Inhibitor 1; D018180:Thrombomodulin; C029417:Von Willebrand antigen; D014841:von Willebrand Factor