Vergleich der Wirksamkeit und Sicherheit zweier künstlicher biologischer Aortenklappen, der Symetis ACURATE neo/TF und der Edwards SAPIEN 3, welche beide über einen Kathetereingriff über die Leistengefässe eingesetzt werden.

Device: Symetis ACURATE neo/TF transfemoral TAVI system;Device: Edwards Sapien 3 Transcatheter Heart Valve

Inclusion Criteria:

- Patient with severe aortic stenosis defined by an aortic valve area (AVA) < 1cm2 or
AVA indexed to body surface area (BSA) of < 0.6 cm2/m2, including low-flow severe
aortic stenosis defined by stroke volume index (SVI) < 35ml/m2, as assessed by
integration of echocardiographic and invasive measurements

- Subject is symptomatic (heart failure symptoms with New York Heart Association (NYHA)
Functional Class > I, angina or syncope)

- Patient is considered at increased risk for mortality if undergoing conventional
surgical aortic valve replacement or judged as not operable as determined either

- by a Logistic EuroSCORE > 20 % OR

- by a STS-PROM score > 10% OR

- by the heart team consisting of at least one cardiologist and cardiac surgeon
based on the integration of individual clinical and anatomical factors not
captured by risk-scores, the patient's age, frailty and life-expectancy

- The heart team agrees on eligibility of the patient for participation and that TAVI by
transfemoral access constitutes the most appropriate treatment modality, from which
the patient will likely benefit most

- Aortic annulus dimensions suitable for both valve types (area range: 338-573 mm2 AND
perimeter range: 66-85 mm) based on ECG-gated multislice computed tomographic
measurements. Findings of transesophageal echocardiography (TEE) and conventional
aortography should be integrated in the anatomic assessment if available

- Arterial aorto-iliac-femoral axis suitable for transfemoral access with a minimum
access vessel diameter = 6 mm as assessed by multislice computed tomographic
angiography and/or conventional angiography

- Written informed consent of the patient or her/his legal representative

- 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

Exclusion Criteria:

- Non-valvular aortic stenosis

- Congenital aortic stenosis or unicuspid or bicuspid aortic valve

- Non-calcific acquired aortic stenosis

- Anatomy not appropriate for transfemoral transcatheter aortic valve implantation due
to size of the aortic annulus or degree or eccentricity of calcification of the native
aortic valve or tortuosity of the aorta or ilio-femoral arteries

- Emergency procedure including patients in cardiogenic shock (low cardiac output,
vasopressor dependence, mechanical hemodynamic support)

- Severely reduced left ventricular (LV) function (ejection fraction < 20%)

- Pre-existing prosthetic heart valve in aortic position

- Presence of mitral valve prosthesis

- Concomitant planned procedure except for percutaneous coronary intervention (PCI)

- Planned non-cardiac surgery within 30 days

- Stroke within 30 days of the procedure.

- Myocardial infarction within 30 days of the procedure (except type 2)

- Evidence of intra-cardiac mass, thrombus or vegetation

- Severe coagulation conditions

- Inability to tolerate anticoagulation/anti-platelet therapy

- Active bacterial endocarditis or other active infections

- Hypertrophic cardiomyopathy with or without obstruction

- Contraindication to contrast media or allergy to nitinol

- 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