Clinical trial aimed at evaluating the safety and performance of the ACURATE neo™ AS Aortic Bioprosthesis and ACURATE neo™ AS TF Transfemoral Delivery System for CE mark approval purposes.

Single arm, prospecitve, multicenter, non-randomized and open trial. The purpose of this trial is to collect and safety and performance data concerning the ACURATE neo™ AS Aortic Bioprosthesis and ACURATE neo™ AS TF Transfemoral Delivery System

The ACURATE neo™ AS Aortic Bioprosthesis and ACURATE neo™ AS TF Transfemoral Delivery System are intended for use in minimally invasive, transcatheter aortic valve replacement (TAVR) using transfemoral access in patients presenting with severe aortic valve stenosis.

The primary objective is to evaluate the safety and performance of the study device in patients presenting with severe aortic stenosis (AS) considered to be high risk for surgery.

The secondary objective is to evaluate adverse events and study device performance.

Inclusion Criteria:

1. Patient 75 years of age and older

2. Severe aortic stenosis defined as:

   • Mean aortic gradient > 40 mmHg or
   • Peak jet velocity > 4.0 m/s or
   • Aortic valve area of < 1.0 cm2

3. High risk candidate for conventional AVR defined as:

   • Logistic EuroSCORE 1 ≥ 20% or
   • STS Score ≥ 8% or
   • Heart team (cardiologist and cardiac surgeon) consensus that patient is not a surgical candidate for conventional AVR due to significant co-morbid conditions unrelated to aortic stenosis

4. NYHA Functional Class > II

5. Aortic annulus diameter from ≥ 21mm up to ≤ 27mm by CT

6. Patient willing to participate in the study and provides signed informed consent

Exclusion Criteria:

1. Congenital aortic stenosis or unicuspid or bicuspid aortic valve
2. Non-stenotic Aortic Insufficiency
3. Severe eccentricity of calcification
4. Severe mitral regurgitation (>2+)
5. Presence of mitral bioprosthesis
6. Presence of previously implanted aortic bioprosthesis
7. Presence of prosthetic ring
8. Anatomy NOT appropriate for transfemoral implant due to the size, disease and degree of calcification or tortuosity of the aorta or ilio-femoral arteries
9. Thoracic (TAA) or abdominal (AAA) aortic aneurysm
10. Presence of endovascular stent graft for treatment of TAA or AAA
11. Trans-oesophageal echocardiogram (TEE) is contraindicated
12. Evidence of intra-cardiac mass, thrombus or vegetation
13. Severe ventricular dysfunction with ejection fraction < 20%
14. Any percutaneous intervention, except for balloon valvuloplasty (BAV) within 1 month prior to implant procedure
15. Acute Myocardial Infarction within 1 month prior to implant procedure
16. Previous TIA or stroke within 3 months prior to implant procedure
17. Active ulcer or gastrointestinal (GI) bleeding within 3 months prior to implant procedure
18. Any scheduled surgical or percutaneous procedure to be performed prior to 30 day visit
19. Severe coagulation conditions
20. Refusal of blood transfusions
21. Systolic pressure <80mmHg, cardiogenic shock, need for inotropic support or IABP
22. Hypertrophic cardiomyopathy with or without obstruction
23. Active bacterial endocarditis or other active infections
24. Hepatic failure (> Child B)
25. Chronic renal dysfunction with serum creatinine > 2.5 mg/dL or renal dialysis
26. Refusal of surgery
27. Severe COPD requiring home oxygen
28. Neurological disease severely affecting ambulation or daily functioning, or dementia
29. Life expectancy < 12 months due to non-cardiac co-morbid conditions
30. Inability to tolerate anticoagulation therapy
31. Contraindication to contrast media or allergy to nickel
32. Currently participating in an investigational drug or another device study
33. Non-valvular aortic stenosis
34. Non-calcific acquired aortic stenosis

The data and study protocol for this clinical trial may be made available to other researchers in accordance with the Boston Scientific Data Sharing Policy (http://www.bostonscientific.com/en-US/data-sharing-requests.html)