Current care randomized clinical trial comparing the CE marked Symetis ACURATE neo™ Aortic Bioprosthesis and ACURATE TF™ Transfemoral Delivery System with the CE marked Medtronic CoreValve Evolut R TAVI system (or any future CE-marked CoreValve versions).

Transcatheter aortic valve implantation (TAVI) is an established and valuable treatment option for patients with severe symptomatic aortic stenosis and at high surgical risk for aortic valve replacement. The use of TAVI is rapidly expanding worldwide and its indications are widening into intermediate and lower risk populations. However, device comparisons by use of randomized trials are scarce in particular for newer generation transcatheter valves.

The Symetis ACURATE neo™, a self-expanding transcatheter valve delivered via transfemoral access, is a second-generation device that gained CE mark approval in June 2014.

The SCOPE-II trial will compare the safety and performance of the Symetis ACURATE neo™ with the self-expanding Medtronic Evolut R system, a widely used and well-established transcatheter heart valve, which obtained CE mark in 8NOV2006 and HAS approval on 13JAN2015.

Inclusion Criteria:

• Patient with severe symptomatic aortic stenosis defined by a mean aortic gradient > 40 mmHg or peak jet velocity > 4.0 m/s or an aortic valve area (AVA) < 1cm2 or AVA indexed to body surface area (BSA) of <0.6 cm2/m2
• Patient is symptomatic (heart failure with New York Heart Association (NYHA) Functional Class > I, angina or syncope)
• Patients are considered at high risk for mortality with conventional surgical aortic valve replacement as assessed by a Heart Team consisting of a cardiologist and surgeon or as confirmed by a logistic EuroSCORE I > 20% and / or STS score > 10%.
• Aortic annulus diameter ranging from 21 to 26mm and perimeter rage from 66 - 81.7mm , based on ECG-gated multi-slice computed tomographic measurements. Findings of TTE, TEE and conventional aortography should be integrated in the anatomic assessment.
• Arterial aorto-iliac-femoral axis suitable for transfemoral access as assessed by conventional angiography and/or multi-detector computed tomographic angiography (access vessel diameter ≥ 6mm)
• Patient understands the purpose, the potential risks as well as benefits of the trial and is willing to participate in all parts of the follow-up
• Patient age 75 years or older
• Patient has given written consent to participate in the trial

Exclusion Criteria:

• Severely reduced left ventricular (LV) function (ejection fraction <20%)
• Pre-existing prosthetic heart valve in aortic and/or mitral position
• Participation in another trial, which would lead to deviations in the preparation or performance of the intervention or the post-implantation management from this protocol
• Severe coagulation conditions
• Inability to tolerate anticoagulation therapy
• Contraindication to contrast media or allergy to nitinol
• Active infection, including endocarditis
• Congenital aortic stenosis or unicuspid or bicuspid aortic valve
• Non-valvular aortic stenosis
• Hypertrophic obstructive cardiomyopathy
• New or untreated echocardiographic evidence of intracardiac mass, thrombus, or vegetation
• Non-calcific acquired aortic stenosis
• Severe eccentricity of calcification
• Anatomy not appropriate for transfemoral implant due to size, disease and degree of calcification or tortuosity of the aorta or ilio-femoral arteries
• Severe mitral regurgitation

764 patients presenting with severe symptomatic aortic stenosis with the indication for TAVI, as agreed by the Heart Team. If all eligibility criteria and none of the exclusion criteria are fulfilled, patients will be allocated in a 1:1 ratio to either the Symetis ACURATE neo™ or the Medtronic CoreValve Evolut R (or any future CE-marked CoreValve versions) by permuted block randomization.