Structural valve deterioration (SVD) is a major obstacle to lifetime durability for bioprosthetic heart valves. A bio-prosthetic valve created with RESILIA™ tissue was designed to produce long-term resistance to SVD. The objective of this study was to evaluate the safety and performance of this new class of RESILIA™ tissue aortic bio-prosthesis. A nonrandomised, prospective, multi-centre, single-arm, observational study was performed in 133 patients who underwent surgical aortic valve replacement between July 2011 and February 2013. Patients were assessed at 3-6 months and one year for haemodynamic performance, clinical outcomes, and functional improvement. The mean age was 65.3 ± 13.5 years, with 34 (25.6%) of patients < 60 years of age. Early (≤ 30 day) and late (> 30 day) all-cause mortality rates were 2.3% (n = 3) and 4.5% (n = 6), respectively. Early events included thromboembolism in three (2.3%) patients and major bleeding events requiring transfusion in six (4.5%) patients. Late events included one endocarditis leading to explant. Mean gradients were reduced across all valve sizes and were maintained at one year of follow-up. The mean effective orifice area and effective orifice area index increased across all valve sizes postoperatively and were maintained at one year. The rates of paravalvular leak (> 2+) at 3-6 months and one-year follow-up were 0.7% and 0.7%, respectively. The new generation RESILIA™ tissue aortic valve bioprosthesis demonstrated excellent haemodynamic per-formance and safety outcomes at one year of follow-up. Longer follow-up of these patients will provide further insight on long-term durability.