title: Impact of valve prosthesis-patient mismatch on left ventricular mass regression following aortic valve replacement.
abstract: BACKGROUND
  Valve prosthesis-patient mismatch is a frequent problem in patients undergoing aortic valve replacement and its main hemodynamic consequence is to generate high transvalvular gradients through normally functioning prosthetic valves. The persistence of high gradients may hinder or delay the regression of left ventricular hypertrophy after aortic valve replacement.
  
  
  METHODS
  The aim of the study was to determine the impact of prosthesis-patient mismatch on the postoperative regression of left ventricular mass. Left ventricular mass was measured by Doppler echocardiography in 109 patients undergoing aortic valve replacement with a single type of bioprosthesis (Carpentier-Edwards Perimount) for pure aortic stenosis. Prosthesis-patient mismatch was defined as a projected indexed effective orifice area less than 0.90 cm2/m2. On this basis, 58/109 (53.2%) patients had prosthesis-patient mismatch.
  
  
  RESULTS
  There was a good correlation (r = 0.61, p < 0.001) between the postoperative mean transprosthetic gradient and the projected indexed effective orifice area. The absolute and relative left ventricular mass regression was significantly (p = 0.002 and p = 0.01, respectively) lower in patients with prosthesis-patient mismatch (-48 +/- 47 g, -17% +/- 16%) compared to those with no prosthesis-patient mismatch (-77 +/- 49 g, -24% +/- 14%). In multivariate analysis, a larger projected indexed effective orifice area, female gender and a higher preoperative left ventricular mass are independent predictors of greater left ventricular mass regression.
  
  
  CONCLUSIONS
  This study shows that in patients with pure aortic stenosis prosthesis-patient mismatch is associated with lesser regression of left ventricular hypertrophy after aortic valve replacement. These findings may have important clinical implications given that prosthesis-patient mismatch is frequent in these patients.
authors.affiliation: Department of Cardiac Surgery, Poliambulanza Hospital, Brescia, Italy. cch-segreteria.poli@poliambulanza.it
authors.forename: Giordano
authors.initials: G
authors.lastname: Tasca
authors.forename: Federico
authors.initials: F
authors.lastname: Brunelli
authors.forename: Marco
authors.initials: M
authors.lastname: Cirillo
authors.forename: Margherita
authors.initials: M
authors.lastname: DallaTomba
authors.forename: Zen
authors.initials: Z
authors.lastname: Mhagna
authors.forename: Giovanni
authors.initials: G
authors.lastname: Troise
authors.forename: Eugenio
authors.initials: E
authors.lastname: Quaini
mesh_terms: D000368:Aged; D001021:Aortic Valve / Q000601:surgery; D001024:Aortic Valve Stenosis / Q000601:surgery*; D001705:Bioprosthesis; D015150:Echocardiography, Doppler; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis / Q000009:adverse effects*; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging* / Q000209:etiology*; D008297:Male; D011300:Preoperative Care; D017755:Prosthesis Fitting