title: Ventriculoarterial coupling in palliated hypoplastic left heart syndrome: Noninvasive assessment of the effects of surgical arch reconstruction and shunt type.
abstract: OBJECTIVE
  To assess the coupling efficiency in hypoplastic left heart syndrome, considering the effect of surgical arch reconstruction and the shunt type received during the Norwood procedure.
  
  
  METHODS
  Ventriculoarterial coupling was assessed before Fontan completion in 32 patients with hypoplastic left heart syndrome (19 modified Blalock-Taussig and 13 Sano shunts at stage 1). Cardiovascular magnetic resonance data were analyzed, deriving functional parameters and 3-dimensional volumes. Dimensional indexes were computed from 3-dimensional data sets as the area ratio of the isthmus to the descending aorta (Risthmus) and the isthmus to surgically enlarged transverse arch (Rarch). Wave intensity was calculated from cardiac magnetic resonance, using the peaks of the forward compression and expansion waves in early and late systole as surrogate indicators of ventriculoarterial coupling.
  
  
  RESULTS
  Aortic distensibility (3.6±2.7×10(-3) 1/mm Hg) was not associated with the time elapsed from stage 1 palliation (P=.94), suggesting an early loss of elasticity that did not progress thereafter. Risthmus was 1.0±0.4, and Rarch was 0.3±0.1, indicating the dilated reconstructed arch was the main anatomic feature. The forward compression wave correlated significantly with Rarch (R2=0.23, P=.006) but not with Risthmus (R2<0.01, P=.63). Patients with a reduced ejection fraction exhibited a larger ventricular mass (R2=0.28, P=.003). The Sano shunt patients had a lower ejection fraction (51%±6% vs 57%±6%, P=.02); however, neither the forward compression nor expansion wave varied significantly between shunt type or the other functional parameters.
  
  
  CONCLUSIONS
  Ventriculoarterial coupling in operated hypoplastic left heart syndrome was affected by aortic arch size mismatch but not by the type of shunt placed at the Norwood operation.
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science, University College London, and Cardiorespiratory Division, Great Ormond Street Hospital for Children, National Health Service Foundation Trust, London, United Kingdom. Electronic address: g.biglino@ucl.ac.uk.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Biglino
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science, University College London, and Cardiorespiratory Division, Great Ormond Street Hospital for Children, National Health Service Foundation Trust, London, United Kingdom.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Giardini
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science, University College London, and Cardiorespiratory Division, Great Ormond Street Hospital for Children, National Health Service Foundation Trust, London, United Kingdom.
authors.forename: Hopewell N
authors.initials: HN
authors.lastname: Ntsinjana
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science, University College London, and Cardiorespiratory Division, Great Ormond Street Hospital for Children, National Health Service Foundation Trust, London, United Kingdom.
authors.forename: Silvia
authors.initials: S
authors.lastname: Schievano
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science, University College London, and Cardiorespiratory Division, Great Ormond Street Hospital for Children, National Health Service Foundation Trust, London, United Kingdom.
authors.forename: Tain-Yen
authors.initials: TY
authors.lastname: Hsia
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science, University College London, and Cardiorespiratory Division, Great Ormond Street Hospital for Children, National Health Service Foundation Trust, London, United Kingdom.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Taylor
mesh_terms: D002675:Child, Preschool; D004548:Elasticity; D005260:Female; D018729:Fontan Procedure; D006801:Humans; D018636:Hypoplastic Left Heart Syndrome / Q000503:physiopathology* / Q000601:surgery*; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D058327:Norwood Procedures; D010166:Palliative Care; D063177:Pulse Wave Analysis; D012189:Retrospective Studies; D016896:Treatment Outcome; D059289:Vascular Stiffness