title: Computational modeling of blood flow in the aorta--insights into eccentric dilatation of the ascending aorta after surgery for coarctation.
abstract: OBJECTIVE
  To assess whether combining a computational modeling technique with data from patient magnetic resonance imaging studies can detect different fluid dynamics and vascular biomechanical properties of the ascending and horizontal aorta in patients with angulated "gothic" arch geometry compared with those with normal "Romanesque" arch geometry after aortic coarctation repair.
  
  
  METHODS
  Advanced computational fluid dynamics techniques (coupled Navier-Stokes and elastodynamics equations) were used to predict the fluid-wall interactions in large arteries. We modeled the fluid dynamics and shear stress in the ascending and horizontal aorta in cases of "gothic" arch and normal "Romanesque" aortic arch geometry. A total of 30 patients after aortic coarctation repair prospectively underwent 3-dimensional magnetic resonance imaging angiography of the thoracic aorta. Measurements of the ascending and horizontal aorta were assessed using multiplanar reformatting images.
  
  
  RESULTS
  Our computational model demonstrated that wall shear stress is greater in those with an angulated "gothic" aortic arch than in those with a "Romanesque" arch. In particular, wall shear stress affected the anterior and posterior segments of the ascending aorta and the inferior and superior segments of the horizontal aorta (vs the left and right segments). In vivo, a "gothic" arch was associated with dilatation of the ascending and horizontal aorta, which was eccentric rather than concentric (P<.05).
  
  
  CONCLUSIONS
  Our results have shown that wall shear stress is eccentric and significantly increased in the ascending and horizontal aorta in patients with a "gothic" aortic arch after repair of coarctation. This suggests that patients with an angulated "gothic" aortic arch might warrant increased surveillance for aortic complications.
authors: Université de Strasbourg, Institut de Recherche Mathématique Avancée, Unité Mixte De Recherche 7501, Strasbourg, France.
authors: Marcela
authors: M
authors: Szopos
authors: Université Pierre et Marie Curie-Paris 6, Faculté de Mathématiques, Unité Mixte De Recherche 7598, Laboratoire JL Lions, Paris, France.
authors: Nicole
authors: N
authors: Poussineau
authors: Université Pierre et Marie Curie-Paris 6, Faculté de Mathématiques, Unité Mixte De Recherche 7598, Laboratoire JL Lions, Paris, France; Division of Applied Mathematics, Brown University, Providence, Rhode Island.
authors: Yvon
authors: Y
authors: Maday
authors: Department of Radiology, University Paris Descartes, Hopital Bichat, Assistance Publique - Hôpitaux de Paris, Paris, France.
authors: Carla
authors: C
authors: Canniffe
authors: Department of Medicine, University of Sydney, Sydney, Australia.
authors: David S
authors: DS
authors: Celermajer
authors: University Paris Descartes, Hopital Necker-Enfants Malades, Assistance Publique - Hôpitaux de Paris, Paris, France.
authors: Damien
authors: D
authors: Bonnet
authors: Department of Radiology, University Paris Descartes, Hopital Bichat, Assistance Publique - Hôpitaux de Paris, Paris, France; University Paris Descartes, Laboratoire MAP5, Unité Mixte De Recherche 8145, Paris, France. Electronic address: phalla.ou@bch.aphp.fr.
authors: Phalla
authors: P
authors: Ou
mesh_terms: D000293:Adolescent; D000328:Adult; D001013:Aorta, Thoracic / Q000503:physiopathology* / Q000601:surgery*; D001017:Aortic Coarctation / Q000503:physiopathology* / Q000601:surgery*; D002648:Child; D003198:Computer Simulation; D004106:Dilatation; D005260:Female; D020342:Finite Element Analysis; D006439:Hemodynamics; D018056:Hemorheology; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D015996:Survival Rate