title: Randomized comparison of stentless versus stented valves for aortic stenosis: effects on left ventricular mass.
abstract: BACKGROUND
  Aortic valve replacement (AVR) is the established treatment for severe aortic stenosis. In response to the long-term results of aortic homografts, stentless porcine valves were introduced as an alternative low-resistance valve. We conducted a randomized trial comparing a stentless with a stented porcine valve in adults with severe aortic stenosis.
  
  
  RESULTS
  The primary outcome was change in left ventricular mass index (LVMI) measured by transthoracic echocardiography and, in a subset, by cardiovascular MR. Measurements were taken before valve replacement and at 6 and 12 months. Patients undergoing AVR with an aortic annulus < or =25 mm in diameter were randomly allocated to a stentless (n=93) or a stented supra-annular (n=97) valve. There were no significant differences in mean LVMI between the stentless versus stented groups at baseline (176+/-62 and 182+/-63 g/m2, respectively) or at 6 months (142+/-49 and 131+/-45 g/m2, respectively), although within-group changes from baseline to 6 months were highly significant. Changes in LVMI measured by cardiovascular MR (n=38) were consistent with the echo findings. There was a greater reduction in peak aortic velocity (P<0.001) and a greater increase in indexed effective orifice area (P<0.001) in the stentless group than in the stented group. There were no differences in clinical outcomes between the 2 valve groups.
  
  
  CONCLUSIONS
  Despite significant differences in indexed effective orifice area and peak flow velocity in favor of the stentless valve, there were similar reductions in left ventricular mass at 6 months with both stented and stentless valves, which persisted at 12 months.
authors.affiliation: Royal Brompton and Harefield NHS Trust, London, UK.
authors.forename: Diego
authors.initials: D
authors.lastname: Perez de Arenaza
authors.forename: Belinda
authors.initials: B
authors.lastname: Lees
authors.forename: Marcus
authors.initials: M
authors.lastname: Flather
authors.forename: Fiona
authors.initials: F
authors.lastname: Nugara
authors.forename: Trygve
authors.initials: T
authors.lastname: Husebye
authors.forename: Marek
authors.initials: M
authors.lastname: Jasinski
authors.forename: Marek
authors.initials: M
authors.lastname: Cisowski
authors.forename: Mohammed
authors.initials: M
authors.lastname: Khan
authors.forename: Michael
authors.initials: M
authors.lastname: Henein
authors.forename: Jullien
authors.initials: J
authors.lastname: Gaer
authors.forename: Levant
authors.initials: L
authors.lastname: Guvendik
authors.forename: Andrzej
authors.initials: A
authors.lastname: Bochenek
authors.forename: Stanislaw
authors.initials: S
authors.lastname: Wos
authors.forename: Mons
authors.initials: M
authors.lastname: Lie
authors.forename: Guido
authors.initials: G
authors.lastname: Van Nooten
authors.forename: Dudley
authors.initials: D
authors.lastname: Pennell
authors.forename: John
authors.initials: J
authors.lastname: Pepper
mesh_terms: D000368:Aged; D001024:Aortic Valve Stenosis / Q000601:surgery*; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009929:Organ Size / Q000502:physiology*; D018579:Patient Selection; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology*; D016277:Ventricular Function, Left / Q000502:physiology