title: Hypertensive changes within the aortic arch of infants and children with isolated coarctation.
abstract: BACKGROUND
  Despite repair, a significant proportion of patients with coarctation of the aorta (CoA) present with late hypertension. Increased gene expression of aortic wall collagen and vascular smooth muscle cell markers occurs in the presence of hypertension. Before repair, a patent ductus arteriosus (PDA) limits hypertension proximal to the coarctation. We hypothesize that preoperative collagen and vascular smooth muscle expression from the aortic arch in children is variable, depending on the presence or absence of a PDA.
  
  
  METHODS
  We analyzed the expression patterns of collagen and vascular smooth muscle cell markers in 25 children with CoA using a quantitative polymerase chain reaction. Aortic arch tissue proximal to the CoA was normalized to descending aortic tissue distal to the coarctation. Collagen-I, transforming growth factor-β, elastin, and calponin were analyzed.
  
  
  RESULTS
  At repair, 19 patients were aged younger than 3 months (14 with a PDA, 5 with a ligamentum arteriosum), and the remaining 6 were older than 1 year. There was no difference in age or weight between infants with or without a PDA. Infants without a PDA had the greatest difference in collagen-I expression compared with infants with a PDA (7.0 ± 1.6-fold vs 0.8 ± 1.1-fold, p = 0.01). Expression of transforming growth factor-β (4.3 ± 1.4 vs 2.6 ± 2.3, p = 0.01) and calponin (3.7 ± 0.7 vs 0.6 ± 1.1, p = 0.05) was lower from infants with vs without a PDA.
  
  
  CONCLUSIONS
  Our findings provide evidence of preoperative changes in the aortic arch before repair, particularly in the absence of a PDA.
authors.affiliation: Pediatric Cardiac Consortium of Upstate New York, Rochester, New York, USA. michael_swartz@urmc.rochester.edu
authors.forename: Michael F
authors.initials: MF
authors.lastname: Swartz
authors.forename: David
authors.initials: D
authors.lastname: Morrow
authors.forename: Nader
authors.initials: N
authors.lastname: Atallah-Yunes
authors.forename: Jill M
authors.initials: JM
authors.lastname: Cholette
authors.forename: Francisco
authors.initials: F
authors.lastname: Gensini
authors.forename: Rae-Ellen
authors.initials: RE
authors.lastname: Kavey
authors.forename: George M
authors.initials: GM
authors.lastname: Alfieris
mesh_terms: D001013:Aorta, Thoracic / Q000000981:diagnostic imaging / Q000378:metabolism / Q000601:surgery; D001017:Aortic Coarctation / Q000150:complications / Q000235:genetics* / Q000601:surgery; D002135:Calcium-Binding Proteins / Q000096:biosynthesis / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D024042:Collagen Type I / Q000096:biosynthesis / Q000235:genetics*; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D005786:Gene Expression Regulation; D006801:Humans; D006973:Hypertension / Q000209:etiology / Q000235:genetics / Q000378:metabolism*; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008840:Microfilament Proteins / Q000096:biosynthesis / Q000235:genetics*; D009131:Muscle, Smooth, Vascular / Q000378:metabolism; D011379:Prognosis; D012313:RNA / Q000235:genetics*; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016212:Transforming Growth Factor beta / Q000096:biosynthesis / Q000235:genetics*; D014656:Vascular Surgical Procedures / Q000379:methods; D000096985:Calponins
chemical_list: D002135:Calcium-Binding Proteins; D024042:Collagen Type I; D008840:Microfilament Proteins; D012313:RNA; D016212:Transforming Growth Factor beta; D000096985:Calponins