title: Impact of the location of the fenestration on Fontan circulation haemodynamics: a three-dimensional, computational model study.
abstract: OBJECTIVE
  There is no consensus or theoretical explanation regarding the optimal location for the fenestration during the Fontan operation. We investigated the impact of the location of the fenestration on Fontan haemodynamics using a three-dimensional Fontan model in various physiological conditions.
  
  
  METHODS
  A three-dimensional Fontan model was constructed on the basis of CT images, and a 4-mm-diameter fenestration was located between the extracardiac Fontan conduit and the right atrium at three positions: superior, middle, and inferior part of the conduit. Haemodynamics in the Fontan route were analysed using a three-dimensional computational fluid dynamic model in realistic physiological conditions, which were predicted using a lumped parameter model of the cardiovascular system. The respiratory effect of the caval flow was taken into account. The flow rate through the fenestration, the effect of lowering the central venous pressure, and wall shear stress in the Fontan circuit were evaluated under central venous pressures of 10, 15, and 20 mmHg. The pulse power index and pulsatile energy loss index were calculated as energy loss indices.
  
  
  RESULTS
  Under all central venous pressures, the middle-part fenestration demonstrated the most significant effect on enhancing the flow rate through the fenestration while lowering the central venous pressure. The middle-part fenestration produced the highest time-averaged wall shear stress, pressure pulse index, and pulsatile energy loss index.
  
  
  CONCLUSIONS
  Despite slightly elevated energy loss, the middle-part fenestration most significantly increased cardiac output and lowered central venous pressure under respiration in the Fontan circulation.
authors.affiliation: 1Department of Cardiovascular Surgery,Kitasato University School of Medicine,Sagamihara,Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Sughimoto
authors.affiliation: 3Graduate School of Engineering,Chiba University,Chiba,Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Asakura
authors.affiliation: 2Department of Cardiac Surgery,The Royal Children's Hospital,Melbourne,Australia.
authors.forename: Christian P
authors.initials: CP
authors.lastname: Brizard
authors.affiliation: 5School of Naval Architecture, Ocean and Civil Engineering,Shanghai Jiao Tong University,Shanghai,China.
authors.forename: Fuyou
authors.initials: F
authors.lastname: Liang
authors.affiliation: 3Graduate School of Engineering,Chiba University,Chiba,Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Fujiwara
authors.affiliation: 1Department of Cardiovascular Surgery,Kitasato University School of Medicine,Sagamihara,Japan.
authors.forename: Kagami
authors.initials: K
authors.lastname: Miyaji
authors.affiliation: 3Graduate School of Engineering,Chiba University,Chiba,Japan.
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
mesh_terms: D002302:Cardiac Output; D002648:Child; D018729:Fontan Procedure / Q000379:methods*; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008955:Models, Cardiovascular; D014057:Tomography, X-Ray Computed
keywords: Fontan; computer fluid dynamics; fenestration; haemodynamics