Prosthesis-patient mismatch in high-risk patients with severe aortic stenosis: A randomized trial of a self-expanding prosthesis

Objectives We compared the incidence of prosthesis-patient mismatch (PPM) between transcatheter aortic valve replacement (TAVR) using a self-expanding bioprosthesis and surgical aortic valve replacement (SAVR) in the CoreValve US High Risk Pivotal Trial. We sought to determine the influence of PPM on clinical outcomes. Methods Patients with severe aortic stenosis and at increased risk for surgery were randomized 1:1 to TAVR or SAVR. Postoperative PPM was defined by the effective orifice area index (EOAi) as severe PPM (EOAi ≤ 0.65 cm²/m²) and no severe PPM (EOAi > 0.65 cm²/m²); clinical outcomes were analyzed in the TAVR arm (n = 389) and SAVR arm (n = 353). Left ventricular mass index and regression were analyzed at baseline and 1 year. Results The incidence of severe PPM in the SAVR group at 1 year was 25.7% versus 6.2% in the TAVR group (P <.0001). Left ventricular mass index regression at 1 year was 6.8% for TAVR and 15.1% for SAVR in patients with severe PPM. At 1 year the rate of all-cause mortality and acute kidney injury were significantly greater in all patients (TAVR + SAVR) with severe PPM compared with no severe PPM (20.6% vs 12.0% [P =.0145] for death and 19.2% vs 8.5% [P =.0008] for acute kidney injury). Conclusions In patients with high surgical risk and severe aortic stenosis, severe PPM is more common in patients treated with SAVR than those treated with TAVR. Patients with severe PPM are a greater risk for death and acute kidney injury than patients without severe PPM.