Feasibility Trial on ACURATE™ Transapical Implantation in Patients With Severe Symptomatic Aortic Stenosis (2009-01)

Inclusion Criteria: * Patients older than 75 years; * Additive EuroSCORE \> 9 and/or STS \> 9%; * Severe symptomatic AS assessed by echocardiography, documented by a derived mean gradient \> 40mmHg,and a native Aortic Valve Area (AVA) \< 0.8 cm² or Aortic Valve Area Index (AVAI) \< 0.6 cm²/m²; * NYHA Functional Class \> II; * Aortic annulus (AAn) diameters between and including 21 mm up to 27 mm (21mm ≤ AAn ≤27mm) by transoesophageal echocardiography; * Sinotubular junction (STJ) higher than 1,1times the native aortic annulus diameter (AAn) \[STJ\>1.1xAAn\] AND STJ\<45mm by transoesophageal echocardiography; * Patient understands the implications of participating in the study and provides signed informed consent Exclusion Criteria: * Congenital unicuspid or bicuspid aortic valve; * Severe eccentricity of calcification; * Severe mitral regurgitation (\> 2°); * Pre-existing prosthetic heart valve in any position and /or prosthetic ring; * Severe transapical access problem, non-reachable LV apex; * Previous surgery of the LV using a patch, such as the Dor procedure; * Presence of apical LV thrombus; * Echocardiographic evidence of intracardiac mass, thrombus, or vegetation; * Acute Myocardial Infarction (AMI) within 1 month prior to the procedure; * PCI within 1 month prior to the procedure; * Previous Transient Ischemic Accident (TIA) or stroke in the last 3 months; * Untreated clinically significant CAD requiring revascularization; * Hemodynamic instability: systolic pressure \<90mmHg without afterload reduction, shock, need for inotropic support or intra-aortic balloon pump; * Severe left ventricular dysfunction with a LV Ejection Fraction (LVEF) \< 25% by echocardiography; * Calcified pericardium; * Septal hypertrophy; * Primary Hypertrophic Obstructive Cardiomyopathy (HOCM); * Active infection, endocarditis or pyrexia; * Active peptic ulcer or Gastrointestinal (GI) bleeding within the past 3 months; * Significant hepatic involvement (Child \> B); * Major lung disease (FEV \< 0.8 or FEV1% \< 30% of normal); * Pulmonary hypertension; * History of bleeding diathesis or coagulopathy; * Hematologic disorder (WBC\<3000mm3, Hb\<9g/dL, platelet count \<50000 cells/ mm3); * Serum creatinine level greater than 3.0 mg/dL or chronic renal failure requiring dialysis; * Neurological disease severely affecting ambulation or daily functioning, including dementia; * Other procedure scheduled at the same time, whether surgery or percutaneous approach; * Emergency procedure; * Life expectancy \< 12 months due to non-cardiac co-morbid conditions; * Known hypersensitivity/contraindication to any study medication, contrast media, or nitinol; * Currently participating in an investigational drug or another device study