Effect of prosthesis-patient mismatch on survival after aortic valve replacement using mechanical prostheses in patients with aortic stenosis.

摘要

BACKGROUND: This study assessed the effects of prosthesis-patient mismatch (PPM) after aortic valve replacement (AVR) using mechanical prostheses in patients with aortic stenosis. METHODS: A total of 124 patients with aortic stenosis who underwent AVR with mechanical prostheses were followed (mean 9.1+/-4.9 years). The patients were divided into two groups based on the effective orifice area index (EOAI): Group A did not have significant PPM, defined as an EOAI>or=0.85 cm2/m2; and the PPM group had significant PPM, defined as an EOAI<0.85 cm2/m2. RESULTS: In all, 25 patients (20.2%) had PPM. The operative mortality was 6.1% in group A and 12.0% in the PPM group; the difference between the groups was not significant. Moreover, the difference in overall survival rates between group A and the PPM group was not statistically significant (15-year postoperative survival: group A 78.5% vs. PPM group 81.3%). Although there were four late deaths in the PPM group, only one was valve-related. PPM had no effect onlate survival. Postoperatively, cardiac function and physical activity levels improved in both groups; the extent of improvement was not dependent on the presence or severity of PPM. CONCLUSION: Although PPM may affect operative mortality, the effect of PPM appears to decrease over time. PPM had no effect on late survival.