Avoidance of patient-prosthesis mismatch

To minimize the incidence of patient-prosthesis mismatch (PPM), we have routinely adopted aortic root enlargement to avoid PPM for patients with small aortic annulus. The aim of this study was to review our strategy of avoiding PPM. The Carpentier-Edwards Perimount (CEP) valves were implanted in 53 patients who were mostly aged over 65 and the St. Jude Medical (SJM) mechanical valves were used in 128 patients aged under 65. A standard 21-mm SJM valve was used in only 3 patients and no 19-mm valves were employed. However, 19-mm CEP valves were used in 12 patients with a small body surface area (1.43 +/- 0.14 m2). Of these, 26 patients (14.4%) who had a small aortic annulus and 24 patients aged under 65 underwent aortic root enlargement. No patient receiving an SJM valve had an projected indexed effective orifice area (EOAI) < or = 0.85 cm2/m2 because of performing aortic valve replacement (AVR) with annular enlargement and only 2 (3.8%) out of 53 patients receiving CEP valves developed PPM. Consequently, the prevalence of PPM was 1.1% in this series. The prevalence of PPM was low in patients over 65 years old with a relatively small body size who received bioprosthetic valves. A pericardial bioprosthesis was considered to be an appropriate valve in older population with regard to avoiding PPM. In patients under 65 years old with a small annulus, the first choice for avoiding PPM is aortic annular enlargement, which may be avoided by high performance mechanical valves with larger EOA.