Impact of valve prosthesis-patient mismatch on left ventricular mass regression following aortic valve replacement.
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.
Tasca
Giordano
G
Department of Cardiac Surgery, Poliambulanza Hospital, Brescia, Italy. cch-segreteria.poli@poliambulanza.it
Brunelli
Federico
F
Cirillo
Marco
M
DallaTomba
Margherita
M
Mhagna
Zen
Z
Troise
Giovanni
G
Quaini
Eugenio
E
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