ACURATE TF™ Transfemoral Aortic Bioprosthesis for Implantation in Patients With Severe Aortic Stenosis:CE-approval Cohort

Inclusion Criteria: 1. Patients 75 years of age and older 2. Logistic EuroSCORE ≥ 20% 3. Severe aortic stenosis characterized by mean aortic gradient \> 40 mmHg or peak jet velocity \> 4.0 m/s or aortic valve area of \< 1.0 cm2 4. New York Heart Association (NYHA) Functional Class \> II 5. Aortic annulus diameter from ≥ 21mm up to ≤ 27mm by Trans-esophageal Echocardiography (TEE) 6. Patient not a surgical candidate due to significant co-morbid conditions unrelated to aortic stenosis 7. Patient willing to participate in the study and provide signed informed consent Exclusion Criteria: 1. Unicuspid or bicuspid aortic valve 2. Extreme eccentricity of calcification 3. Severe mitral regurgitation ( \>2+) 4. Pre-existing prosthetic heart valve in any position and / or prosthetic ring 5. Aortic or peripheral anatomy NOT appropriate for transfemoral implant 6. Thoracic (TAA) or abdominal (AAA) aortic aneurysm 7. Presence of endovascular stent graft for treatment of TAA or AAA 8. TEE is contraindicated 9. Left Ventricular Ejection Fraction (LVEF) \< 30% by echocardiography (ECHO) 10. ECHO evidence of intracardiac mass, thrombus, or vegetation 11. Acute Myocardial Infarction (AMI) within 1 month prior to implant procedure 12. Percutaneous Coronary Intervention (PCI), except for balloon valvuloplasty (BAV) within 1 month prior to implant procedure 13. Previous Transien Ischemic Attack (TIA) or stroke within 3 months prior to implant procedure 14. Active ulcer or gastrointestinal (GI) bleeding within 3 months prior to implant procedure 15. Any scheduled surgical or percutaneous procedure to be performed prior to 30 day visit 16. History of bleeding diathesis or coagulopathy or refusal of blood transfusions 17. Systolic pressure \<80 mmHg, cardiogenic shock, need for inotropic support or Intra-Aortic Balloon Pump (IABP) 18. Primary hypertrophic obstructive cardiomyopathy (HOCM) 19. Active infection, endocarditis or pyrexia 20. Hepatic failure 21. Chronic renal dysfunction with serum creatinine \> 2.5 mg/dL or renal dialysis 22. Refusal of surgery 23. Severe Chronic Obstructive Pulmonary Disease (COPD) requiring home oxygen 24. Neurological disease severely affecting ambulation or daily functioning, or dementia 25. Life expectancy \< 12 months due to non-cardiac co-morbid conditions 26. Known hypersensitivity/contraindication to study medication, contrast media, or nitinol 27. Currently participating in an investigational drug or another device study