title: The RV-PA conduit stimulates better growth of the pulmonary arteries in hypoplastic left heart syndrome.
abstract: OBJECTIVE
  This retrospective study compared the size of the central pulmonary arteries in patients with hypoplastic left heart syndrome (HLHS) following either a classical Norwood or Norwood procedure with a right ventricle to pulmonary artery (RV-PA) conduit.
  
  
  METHODS
  Between May 2001 and May 2003, 30 patients with HLHS underwent cardiac catheterization prior to stage II palliation. Patients were initially palliated with a classical Norwood (Classical group, n=18) or Norwood procedure with RV-PA conduit (RV-PA group; n=12). Indexed maximum and minimum diameters of the LPA and RPA were measured using the McGoon ratio. Cardiac catheterisation was performed at a median age of 4.0 months. There was no difference in the time interval to catheterisation (P=0.13), Qp:Qs (P=0.41) or median haemoglobin (P=0.42) between the groups.
  
  
  RESULTS
  The combined PA diameter was larger in the RV-PA group (B) than the classical group (A) (1.99+/-0.38 versus 1.63+/-0.29, P<0.05). There were marked differences in the relative size of the pulmonary arteries between the two groups. In RV-PA patients, the LPA and RPA sizes were comparable (0.99+/-0.22 versus 1.00+/-0.31, P=1.00) whereas, in the classical group, the LPA was smaller than the RPA (0.75+/-0.15 versus 0.88+/-0.17, P<0.05). Both techniques were also associated with discrete PA stenoses at the site of shunt insertion. Stenoses were more severe in RV-PA group (RV-PA), causing a 42+/-16% reduction in the combined PA diameter compared with a 28+/-18% reduction in Classical group (classical) (P<0.05).
  
  
  CONCLUSIONS
  The Norwood procedure with RV-PA conduit is associated with better and more evenly distributed central pulmonary artery growth. Nevertheless, it is also associated with central PA stenoses, which may require subsequent reconstruction.
authors.affiliation: Department of Paediatric Cardiac Surgery, Diana, Princess of Wales Children's Hospital, Steelhouse Lane, Birmingham B4 6NH, UK.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Rumball
authors.forename: Simon P
authors.initials: SP
authors.lastname: McGuirk
authors.forename: Oliver
authors.initials: O
authors.lastname: Stümper
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Laker
authors.forename: Joseph V
authors.initials: JV
authors.lastname: de Giovanni
authors.forename: John G
authors.initials: JG
authors.lastname: Wright
authors.forename: David J
authors.initials: DJ
authors.lastname: Barron
authors.forename: William J
authors.initials: WJ
authors.lastname: Brawn
mesh_terms: D000714:Anastomosis, Surgical; D019917:Blood Vessel Prosthesis Implantation; D006328:Cardiac Catheterization; D006348:Cardiac Surgical Procedures; D003251:Constriction, Pathologic; D006352:Heart Ventricles / Q000473:pathology / Q000601:surgery; D006801:Humans; D018636:Hypoplastic Left Heart Syndrome / Q000473:pathology / Q000601:surgery*; D007223:Infant; D007231:Infant, Newborn; D010166:Palliative Care; D011651:Pulmonary Artery / Q000473:pathology / Q000601:surgery*; D012189:Retrospective Studies