Prosthesis-patient mismatch affects late survival after valve surgery for severe aortic stenosis

BACKGROUND: The effect of prosthesis-patient mismatch (PPM) on late survival after aortic valve replacement (AVR) in patient with symptomatic severe aortic stenosis (AS) remains unclear. Also, late follow-up in previous studies is confined to only one decade. We aimed to determine the effect of PPM on late survival after isolated AVR for symptomatic severe AS during 25 years of follow-up. METHODS: In this retrospective cohort study, Kaplan-Meier survival analysis was performed to determine late survival in 404 consecutive patients with moderate PPM (N.=86), severe (N.=11), or no/mild PPM (N.=307) after isolated AVR for symptomatic severe AS during a mean follow-up of 25.0 +/- 2.9 years. Moderate, severe, and no/mild PPM were defined as indexed effective orifice area of >0.65 <= 0.85, <= 0.65, and >0.85 cm(2)/m(2), respectively. Multivariable analysis was performed to identify possible independent predictors of decreased late survival, including moderate or severe PPM. RESULTS: Late survival of patients with severe PPM was worse in comparison with those with no/mild PPM: 7.4 +/- 2.6 (95% confidence interval 2.2-12.5) vs. 13.6 +/- 0.5 (95% confidence interval 12.6-14.6) years, respectively; P=0.020. Late survival of patients with moderate PPM was similar to those with no/mild PPM. Severe PPM was an independent predictor of decreased late survival: hazards ratio 4.002 (95% confidence interval 1.869-8.569); P<0.001. Moderate PPM was not an independent predictor of decreased late survival. CONCLUSIONS: Severe PPM was independently associated with decreased late survival after isolated AVR for symptomatic severe AS during a mean follow-up of 25.0 +/- 2.9 years. Therefore, severe PPM should be prevented as much as possible.