Aortic valve replacement with smaller prostheses in elderly patients: does patient prosthetic mismatch affect outcomes?

BACKGROUND AND AIM OF THE STUDY: To evaluate the influence of patient-prosthesis mismatch (PPM) on survival, and quality of life (QOL) after aortic valve replacement (AVR) in elderly patients with small prosthesis size. METHODS: Between 2005 and 2010, 142 patients older than 65 years were discharged from the hospital after AVR with 19 or 21 mm prosthesis for aortic stenosis. Their median age was 79 years (range 66 to 91). Prosthesis effective orifice area (EOA) was derived from the continuity equation and PPM was defined as an indexed EOA (IEOA) < 0.85 cm(2)/m(2). Patients having IEOA < 0.75 cm(2)/m(2) and IEOA < 0.60 cm(2)/m(2) were also investigated. Mean follow-up was 23 months (range 1 to 58) and was 98% complete. RESULTS: PPM was found in 86 patients, 63 had an IEOA = 0.75 cm(2) /m(2), and 23 had an IEOA = 0.60 cm(2) /m(2). The groups were similar except for older age (p = 0.0364), larger body surface area (p = 0.0068), more male gender (p = 0.0186), and more EF < 40% in patients with PPM. Survival at 58 months was 81 ± 6.4% and was not influenced by PPM (p = 0.9845). At Cox analysis only preoperative NYHA class (p = 0.0064) was identified as an independent risk factor for late death. The SF12 test was used to analyze the QOL of patients and it did not reveal differences between groups. CONCLUSIONS: PPM does not affect survival in this series of elderly patients. We believe that more aggressive surgical procedures are not justified in these patients.