title: In vitro evaluation of aortic valve prosthesis in a novel valved conduit with pseudosinuses of Valsalva.
abstract: OBJECTIVE
  This study was undertaken to determine whether the presence of vortices immediately above a prosthetic aortic valve could negatively influence the in vitro hydrodynamic performances of a biologic or mechanical valve implanted in a new Dacron polyester fabric conduit that incorporates sculpted sinuses of Valsalva.
  
  
  METHODS
  With a computer-controlled pulse duplicator, the in vitro performance (pressure differences, closure and leakage volumes, and energy losses) of a 25-mm mechanical or biologic prosthesis implanted in a standard Dacron straight conduit or in the new Dacron graft with a sculpted sinus were analyzed and compared.
  
  
  RESULTS
  The mechanical and biologic prostheses at 7 L/min cardiac output showed pressure drops across the valve of 8.72 mm Hg and 13.45 mm Hg, respectively, when inserted in the new Valsalva-style graft and of 7.97 mm Hg and 12.94 mm Hg, respectively, when inserted in the standard graft. The closure and leakage volumes for mechanical valves were higher than those for biologic valves; however, the presence or absence of sinuses did not result in significant differences in closure and leakage volumes. The maximal total energy losses were 5.89% and 9.49% for mechanical and biologic valves, respectively. No differences were evident between the two different Dacron grafts for each prosthetic heart valve.
  
  
  CONCLUSIONS
  The normal opening and closing behavior of a prosthetic aortic valve was not altered or modified by a different root shape above the heart valve. The presence of vortices inside the pseudosinuses of Valsalva did not influence the hydrodynamic properties of the biologic and mechanical valves tested.
authors.affiliation: Cardiac Surgery Department, University of Tor Vergata, Rome, Italy. depauli@tin.it
authors.forename: Ruggero
authors.initials: R
authors.lastname: De Paulis
authors.forename: Christoph
authors.initials: C
authors.lastname: Schmitz
authors.forename: Raffaele
authors.initials: R
authors.lastname: Scaffa
authors.forename: Paolo
authors.initials: P
authors.lastname: Nardi
authors.forename: Luigi
authors.initials: L
authors.lastname: Chiariello
authors.forename: Helmut
authors.initials: H
authors.lastname: Reul
mesh_terms: D001021:Aortic Valve; D055592:Biophysical Phenomena; D001703:Biophysics; D006350:Heart Valve Prosthesis; D066298:In Vitro Techniques; D011474:Prosthesis Design; D012850:Sinus of Valsalva