title: Impact of synthetic elements on aortic root haemodynamics: computed fluid dynamics of aortic root reconstruction and valve reimplantation.
abstract: The aim was to evaluate the impact of the aortic valve reimplantation (David) and of the aortic root (AoR) remodelling (Yacoub) on the AoR haemodynamics.
  
  
  
  In an experimental setup where the clinical scenario of Yacoub, ( n =  5, domestic pig) and of David ( n =  5, domestic pig) procedure was performed in each AoR, six high-fidelity (200 Hz) sonomicrometric crystals were implanted. Crystals were positioned at three commissures with their projection at the root base. In post-measurement processing 3D deformation of both AoR was determined and used for computed fluid dynamic modelling in order to evaluate pressure, velocity and shear stress profiles.
  
  
  
  In David AoR: high pressure (> 150 mmHg) and low to moderate shear stress (0-30 Pa) were found from the period of isovolemic contraction to the closure of the aortic valve. At mid diastole pressure augmentation (> 120 mmHg) a low shear stress (0-10 Pa) was registered at the leaflets, three commissures, and intervalvular triangles. In Yacoub AoR: high pressure (110-130 mmHg) with moderate low shear stress (0-30 Pa) was only registered at isovolemic contraction.
  
  
  
  The results show that haemodynamic conditions following a David procedure have a less favourable pattern as compared to a Yacoub AoR. In David AoR, high pressure and low shear stress are present during 2/3 of the cardiac cycle, whereas in Yacoub root, these conditions are present only for a short period of isovolemic contraction.
authors.affiliation: Department of Surgery and Anesthesiology, Cardiovascular Research, University Hospital Lausanne, Lausanne, Switzerland.|Department of Cardiac Surgery, University Hospital Basel, Basel, Switzerland.
authors.forename: Denis
authors.initials: D
authors.lastname: Berdajs
authors.affiliation: Department of Surgery and Anesthesiology, Cardiovascular Research, University Hospital Lausanne, Lausanne, Switzerland.
authors.forename: Selim
authors.initials: S
authors.lastname: Mosbahi
authors.affiliation: Department of Surgery and Anesthesiology, Cardiovascular Research, University Hospital Lausanne, Lausanne, Switzerland.
authors.forename: Francesco
authors.initials: F
authors.lastname: Strano
authors.affiliation: Swiss Federal Institution of Technology Zürich, Zürich, Switzerland.
authors.forename: Zalan
authors.initials: Z
authors.lastname: Forro
authors.affiliation: Department of Surgery and Anesthesiology, Cardiovascular Research, University Hospital Lausanne, Lausanne, Switzerland.
authors.forename: Marco
authors.initials: M
authors.lastname: Burki
authors.affiliation: Department of Surgery and Anesthesiology, Cardiovascular Research, University Hospital Lausanne, Lausanne, Switzerland.
authors.forename: Ludwig K
authors.initials: LK
authors.lastname: von Segesser
mesh_terms: D000818:Animals; D001011:Aorta / Q000503:physiopathology / Q000601:surgery*; D001021:Aortic Valve / Q000503:physiopathology / Q000601:surgery*; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D019917:Blood Vessel Prosthesis Implantation / Q000379:methods*; D006439:Hemodynamics; D057446:Hydrodynamics; D012092:Replantation / Q000379:methods; D013314:Stress, Mechanical; D034421:Sus scrofa
keywords:  Aortic root ; Aortic valve ; Computed fluid dynamics