title: Hemodynamic performance of stented and stentless aortic bioprostheses.
abstract: BACKGROUND
  This study compares the hemodynamic performance of stented and stentless bioprostheses used for aortic valve replacement in patients with aortic stenosis and small aortic root.
  
  
  METHODS
  Between 1995 and 1998, 37 patients with a 21-mm aortic annulus (group 1) underwent aortic valve replacement with either a 21-mm Edwards Perimount or a 23-mm St. Jude Toronto bioprosthesis whereas 47 patients with a 23-mm aortic annulus (group 2) received either a 23-mm Medtronic Mosaic or a 25-mm Edwards Prima bioprosthesis. In each group mean and peak gradients, effective orifice area index, and left ventricular mass index were compared during follow-up.
  
  
  RESULTS
  Group 1 patients showed a significant reduction of mean (p < 0.001) and peak gradients (p = 0.001) during follow-up, more evident for St. Jude Toronto versus Edwards Perimount (p = 0.02 and p = 0.05, respectively). Group 2 patients showed a significant reduction of mean and peak gradients (p < 0.001), more evident for Edwards Prima versus Medtronic Mosaic (p < 0.001 and p = 0.07, respectively). Effective orifice area index significantly increased only in group 1 (p = 0.005). Left ventricular mass index significantly decreased in all patients regardless of the type of valve (p < 0.001). Patients with Edwards Prima showed a trend to a higher regression of left ventricular mass index versus Medtronic Mosaic recipients (p = 0.07).
  
  
  CONCLUSIONS
  After aortic valve replacement, stented and stentless bioprostheses exhibited similar results with a more evident hemodynamic improvement during follow-up in the stentless valves. Stented bioprostheses of new generation, however, may parallel the hemodynamic performance of stentless valves and appear to be a valid alternative for aortic valve replacement in elderly patients with a small aortic annulus.
authors.affiliation: Cardiac and Thoracic Department, University of Pisa Medical School, Italy.
authors.forename: A D
authors.initials: AD
authors.lastname: Milano
authors.forename: C
authors.initials: C
authors.lastname: Blanzola
authors.forename: G
authors.initials: G
authors.lastname: Mecozzi
authors.forename: A
authors.initials: A
authors.lastname: D'Alfonso
authors.forename: M
authors.initials: M
authors.lastname: De Carlo
authors.forename: C
authors.initials: C
authors.lastname: Nardi
authors.forename: U
authors.initials: U
authors.lastname: Bortolotti
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000503:physiopathology / Q000601:surgery*; D001705:Bioprosthesis; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D005260:Female; D006350:Heart Valve Prosthesis; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D011183:Postoperative Complications / Q000503:physiopathology*; D011474:Prosthesis Design; D012189:Retrospective Studies; D015607:Stents