Prosthesis-patient mismatch after transcatheter aortic valve implantation using the Edwards SAPIEN™ prosthesis.
OBJECTIVE
Prosthesis-patient mismatch (PPM) is defined as a too small effective orifice area (EOA) of the prosthetic valve in relation to the patient's body size and has been documented to be related to adverse outcomes after conventional aortic valve replacement (AVR). Aim of this study was to analyze the incidence of PPM after transcatheter aortic valve implantation (T-AVI) using the Edwards SAPIEN prosthesis and its relation to postoperative outcome.


METHODS
200 consecutive high-risk patients underwent transapical aortic valve implantation (TA-AVI) between February 2006 and January 2009 and fulfilled 1 year follow-up were included. Severe PPM was defined as indexed EOA (EOAi) <0.65 cm2/m2 and moderate PPM as EOAi = 0.65-0.85 cm2/m2, EOA was calculated from transthoracic echocardiographic (TTE) measurements using the continuity equation. Total 112 patients with sufficient postoperative TTE image quality formed the study group.


RESULTS
EOAi increased from 0.3 ± 0.1 cm2/m2 (preoperatively) to 1.1 ± 0.4 cm2/m2 after TA-AVI (p < 0.001). According to the standard definitions, PPM was seen in 38.4% of the patients and 9.8% presented with severe PPM. The occurrence of PPM had neither an effect on clinical outcome in terms of NYHA class nor on survival. Patients with PPM had significantly higher postoperative transprosthetic gradients (mean gradient 10.4 ± 4.1 versus 7.1 ± 3.0 mm Hg, p < 0.001). Based on the in vitro EOA data obtained from pulse duplicator measurements, however, none of the patients was judged to have PPM.


CONCLUSIONS
Transcatheter AVI provides good antegrade hemodynamic function and EOAi improves significantly. According to standardized evaluations PPM occurs after TA-AVI, but it is not associated with adverse outcomes. Thus use of the continuity equation may not adequately reflect the situation after T-AVI or the current definition of PPM is not suitable for T-AVI prostheses.
Department of Cardiac Surgery, Heartcenter University of Leipzig, Germany.
Arnaud
A
Van Linden
Jörg
J
Kempfert
Johannes
J
Blumenstein
Ardawan
A
Rastan
David
D
Holzhey
Sven
S
Lehmann
Friedrich W
FW
Mohr
Thomas
T
Walther
D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000503:physiopathology; D001024:Aortic Valve Stenosis / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D049628:Body Size; D006328:Cardiac Catheterization / Q000009:adverse effects* / Q000295:instrumentation* / Q000401:mortality; D016009:Chi-Square Distribution; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects* / Q000295:instrumentation* / Q000379:methods / Q000401:mortality; D006439:Hemodynamics; D017052:Hospital Mortality; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D011474:Prosthesis Design; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome; D014463:Ultrasonography