title: Evolving strategies and improving outcomes of the modified norwood procedure: a 10-year single-institution experience.
abstract: BACKGROUND
  This study reviews our 10-year experience with the modified Norwood procedure to determine its early and midterm outcomes. The focus is on the impact of evolving management strategies and accumulated institutional experience.
  
  
  METHODS
  A modified Norwood operation was performed in 171 infants over a 10-year period. Sixty-eight percent of the infants were male, the median age at operation was 6 days (range 1 to 175 days), and the median weight was 3.3 kg (range 1.7 to 4.8 kg). The 10-year period was divided into three eras: era I; 1990 through 1993; era II; 1994 through 1997; and era III; 1998 into 2000. Outcomes and risk factors for mortality were sought.
  
  
  RESULTS
  Hypoplastic left heart syndrome or a variant was the primary diagnosis in 118 infants (69%). The overall 5-year survival rate was 43%. Multivariate analysis revealed that only need of preoperative ventilatory support, earlier date of operation, and lower weight at operation were significant independent predictors of increased time-related mortality. Morphologic features such as a diagnosis other than hypoplastic left heart syndrome, ascending aortic size, and noncardiac anomalies were not significantly associated with an increased risk of death. The hospital survival rate for stage-one palliation in era III was 82%, significantly better than that in the preceding eras (p < 0.001). Attrition between stages one and two accounted for a 15% mortality rate among hospital survivors.
  
  
  CONCLUSIONS
  With increasing experience and improvements in perioperative care and surgical technique, good outcomes can be expected for the first-stage modified Norwood procedure. Greater monitoring of patients in the interstage period may reduce interval mortality and improve overall survival.
authors.affiliation: Department of Surgery, The Hospital for Sick Children, University of Toronto School of Medicine, Ontario, Canada. tony.azakie@utoronto.ca
authors.forename: T
authors.initials: T
authors.lastname: Azakie
authors.forename: S L
authors.initials: SL
authors.lastname: Merklinger
authors.forename: B W
authors.initials: BW
authors.lastname: McCrindle
authors.forename: G S
authors.initials: GS
authors.lastname: Van Arsdell
authors.forename: K J
authors.initials: KJ
authors.lastname: Lee
authors.forename: L N
authors.initials: LN
authors.lastname: Benson
authors.forename: J G
authors.initials: JG
authors.lastname: Coles
authors.forename: W G
authors.initials: WG
authors.lastname: Williams
mesh_terms: D005260:Female; D005500:Follow-Up Studies; D016027:Heart Transplantation; D006801:Humans; D018636:Hypoplastic Left Heart Syndrome / Q000401:mortality / Q000601:surgery*; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010166:Palliative Care; D011183:Postoperative Complications / Q000401:mortality; D012086:Reoperation; D012307:Risk Factors; D015996:Survival Rate; D016896:Treatment Outcome