title: Influence of surgical arch reconstruction methods on single ventricle workload in the Norwood procedure.
abstract: OBJECTIVE
  The study objective was to evaluate various types of Norwood arch reconstruction methods and to show the factors that affect the cardiac workload of the single ventricle. The Norwood procedure is one of the most challenging congenital heart surgeries. Several aortic arch reconstruction techniques have been reported to avoid recoarctation, ensure coronary perfusion, and improve long-term outcomes. Inside the arch, complicated turbulent flow is generated; however, little is known about the cause of the disadvantageous inefficient flow and the surgical techniques to avoid it.
  
  
  METHODS
  We created patient-specific computational hemodynamic models of 9 patients who underwent different types of arch reconstruction methods. Four patients had aortic atresia, and 5 patients had aortic stenosis. Flow profiles were defined by echocardiography data corrected with body surface area. Turbulent pulsatile flow was analyzed with the finite volume method. Flow energy loss was calculated to estimate cardiac workload, and wall shear stress was calculated to estimate vessel wall stiffness increase.
  
  
  RESULTS
  Recoarctation and acute arch angles increased wall shear stress and energy loss. In the patients with aortic atresia, a longitudinal incision toward the descending aorta was effective in creating a smooth arch angle. In the patients with aortic stenosis, arch repair with the Damus-Kaye-Stansel procedure in a single anastomotic site was effective in creating sufficient anastomosis space and a smooth arch angle.
  
  
  CONCLUSIONS
  Creation of a large anastomotic space and a smooth aortic arch angle reduced wall shear stress and energy loss, and should improve long-term cardiac performance after the Norwood procedure.
authors: Department of the Cardiovascular Surgery, Kitasato University School of Medicine, Kanagawa, Japan.
authors: Keiichi
authors: K
authors: Itatani
authors: Kagami
authors: K
authors: Miyaji
authors: Yi
authors: Y
authors: Qian
authors: Jin Long
authors: JL
authors: Liu
authors: Tomoyuki
authors: T
authors: Miyakoshi
authors: Arata
authors: A
authors: Murakami
authors: Minoru
authors: M
authors: Ono
authors: Mitsuo
authors: M
authors: Umezu
mesh_terms: D001013:Aorta, Thoracic / Q000002:abnormalities / Q000503:physiopathology / Q000601:surgery*; D001017:Aortic Coarctation / Q000503:physiopathology / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000151:congenital / Q000503:physiopathology / Q000601:surgery*; D002675:Child, Preschool; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007223:Infant; D008297:Male; D058327:Norwood Procedures; D011673:Pulsatile Flow; D016896:Treatment Outcome