title: In vitro investigation of a novel elastic vascular prosthesis for valve-sparing aortic root and ascending aorta replacement.
abstract: OBJECTIVE
  Prosthetic replacement of the thoracic aorta with common Dacron prostheses impairs the aortic 'windkessel' and, in valve-sparing procedures, also aortic valve function. Elastic graft material may overcome these deficiencies.
  
  
  METHODS
  Fresh porcine aortas including the root were set up in a mock circulation before and after replacement of the ascending part with a novel vascular prosthesis providing elastic behaviours. In a first series (n = 14), haemodynamics and leaflet motions of the aortic valve were investigated and also cyclic changes of aortic dimensions at different levels of the root. In a second series (n = 7), intravascular pressure and dimensions of the proximal descending aorta were measured and the corresponding wall tension was calculated.
  
  
  RESULTS
  Haemodynamics of the aortic valve remain comparable after replacement. Though the novel prosthesis does not feature such high distensibility as the native aorta, the dynamic of the root was significantly increased compared with common Dacron prostheses at the commissural level, preserving 'windkessel' function. Thus, wall tension of the residual aorta remained unchanged; nevertheless, maximum pressure-time differential dp/dt increased by 13%.
  
  
  CONCLUSIONS
  The use of the novel elastic prosthesis for replacement of the ascending aorta seems to be beneficial, especially with regard to the preservation of the aortic windkessel. Further studies will be needed to clarify long-term utilization of the material in vivo.
authors.affiliation: Department of Cardiac Surgery, University Clinic of Schleswig-Holstein, Lübeck, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Scharfschwerdt
authors.affiliation: Department of Cardiac Surgery, University Clinic of Schleswig-Holstein, Lübeck, Germany.
authors.forename: Moritz
authors.initials: M
authors.lastname: Leonhard
authors.affiliation: Department of Cardiac Surgery, University Clinic of Schleswig-Holstein, Lübeck, Germany.
authors.forename: Judith
authors.initials: J
authors.lastname: Lehmann
authors.affiliation: Department of Cardiac Surgery, University Clinic of Schleswig-Holstein, Lübeck, Germany.
authors.forename: Doreen
authors.initials: D
authors.lastname: Richardt
authors.affiliation: Department of Cardiac Surgery, University Clinic of Schleswig-Holstein, Lübeck, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Goldmann
authors.affiliation: Department of Cardiac Surgery, University Clinic of Schleswig-Holstein, Lübeck, Germany Department of Cardiac and Thoracic Vascular Surgery, University of Lübeck, Lübeck, Germany hans-hinrich.sievers@uksh.de.
authors.forename: Hans-Hinrich
authors.initials: HH
authors.lastname: Sievers
mesh_terms: D000818:Animals; D001011:Aorta / Q000601:surgery*; D001021:Aortic Valve / Q000601:surgery*; D001794:Blood Pressure; D019917:Blood Vessel Prosthesis Implantation / Q000295:instrumentation*; D004548:Elasticity; D006350:Heart Valve Prosthesis; D008422:Materials Testing; D008955:Models, Cardiovascular; D011140:Polyurethanes / Q000737:chemistry*; D011474:Prosthesis Design; D013552:Swine
chemical_list: D011140:Polyurethanes
keywords: Aorta, thoracic; Blood pressure; Blood vessel prosthesis; Blood vessel prosthesis implantation; Elasticity; Polyurethane