title: Hybrid versus Norwood strategies for single-ventricle palliation.
abstract: BACKGROUND
  Hybrid and Norwood strategies differ substantially in terms of stage II palliative procedures. We sought to compare these strategies with an emphasis on survival and reintervention after stage II and subsequent Fontan completion.
  
  
  RESULTS
  Of 110 neonates with functionally single-ventricle physiology who underwent stage I palliation between 2004 and 2010, 75 (69%) infants (Norwood, n=43; hybrid, n=32) who subsequently underwent stage II palliation were studied. Survival and reintervention rates after stage II palliation, anatomic and physiologic variables at pre-Fontan assessment, and Fontan outcomes were compared between the groups. Predictors for reintervention were analyzed. Freedom from death/transplant after stage II palliation was equivalent between the groups (Norwood, 80.4% versus hybrid, 85.6% at 3 years, P=0.66). Hybrid patients had a higher pulmonary artery (PA) reintervention rate (P=0.003) and lower Nakata index at pre-Fontan evaluation (P=0.015). Aortic arch and atrioventricular valve reinterventions were not different between the groups. Ventricular end-diastolic pressure, mean PA pressure, and ventricular function were equivalent at pre-Fontan assessment. There were no deaths after Fontan completion in either group (Norwood, n=25, hybrid, n=14).
  
  
  CONCLUSIONS
  Survival after stage II palliation and subsequent Fontan completion is equivalent between the groups. The hybrid group had a higher PA reintervention rate and smaller PA size. Both strategies achieved adequate physiology for Fontan completion. Evolution of the hybrid strategy requires refinement to provide optimal PA growth.
authors.affiliation: Division of Cardiovascular Surgery, The Labatt Family Heart Centre, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Kenji
authors.initials: K
authors.lastname: Baba
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kotani
authors.forename: Devin
authors.initials: D
authors.lastname: Chetan
authors.forename: Rajiv R
authors.initials: RR
authors.lastname: Chaturvedi
authors.forename: Kyong-Jin
authors.initials: KJ
authors.lastname: Lee
authors.forename: Lee N
authors.initials: LN
authors.lastname: Benson
authors.forename: Lars
authors.initials: L
authors.lastname: Grosse-Wortmann
authors.forename: Glen S
authors.initials: GS
authors.lastname: Van Arsdell
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Caldarone
authors.forename: Osami
authors.initials: O
authors.lastname: Honjo
mesh_terms: D001013:Aorta, Thoracic / Q000601:surgery; D058366:Blalock-Taussig Procedure / Q000379:methods* / Q000706:statistics & numerical data; D005260:Female; D018729:Fontan Procedure / Q000706:statistics & numerical data; D016027:Heart Transplantation / Q000706:statistics & numerical data; D006352:Heart Ventricles / Q000601:surgery; D006801:Humans; D018636:Hypoplastic Left Heart Syndrome / Q000401:mortality / Q000601:surgery*; D007223:Infant; D007231:Infant, Newborn; D053208:Kaplan-Meier Estimate; D008943:Mitral Valve / Q000601:surgery; D058327:Norwood Procedures / Q000379:methods* / Q000706:statistics & numerical data; D010166:Palliative Care; D011183:Postoperative Complications / Q000401:mortality; D011651:Pulmonary Artery / Q000601:surgery; D012086:Reoperation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D016896:Treatment Outcome; D014261:Tricuspid Valve / Q000601:surgery