The influence of patient-prosthesis mismatch on in-hospital complications and early mortality after aortic valve replacement.

BACKGROUND AND AIM OF THE STUDY: The study aim was to analyze the relationship between patient-prosthesis mismatch (PPM) and in-hospital complications and mortality after aortic valve replacement (AVR).

METHODS: AVR was performed in 1,819 patients between January 1996 and July 2006. Follow up investigations were performed after a mean of 4.3 years (range: 0 days to 10.6 years). Univariate and multivariate analysis were used to evaluate risk factors for in-hospital complications and mortality in patients with prosthesis mismatch. Actuarial statistics were used to calculate survival rates.

RESULTS: Multivariate analysis showed that PPM (defined as indexed effective orifice area < or = 0.85 cm2/m2) was associated with an increased risk of postoperative neurological events (OR 2.26, 95% CI 1.05-4.83, p = 0.037). There were no significant differences in 30-day mortality between the PPM and non-PPM groups. Neither was any significant difference found between the two groups regarding long-term survival adjusted for significant risk factors for death after AVR.

CONCLUSION: The results suggest PPM to be an independent predictor of postoperative neurological complications in patients undergoing AVR. However, PPM did not negatively influence either short- or long-term survival. PPM may play an important role in selected categories of patients, and should be considered in order to avoid postoperative neurological complications.