Medtronic CoreValve Evolut R U.S. Clinical Study (Evolut 34R Addendum)

Inclusion Criteria

• Severe aortic stenosis, defined as aortic valve area of 40 mmHg or maximal aortic valve velocity > 4.0 m/sec by resting echocardiogram.

Subjects with low-flow/low gradient severe aortic stenosis can be included, provided low-dose dobutamine or exercise stress echocardiography demonstrates a mean gradient of > 40 mmHg or a maximal aortic valve velocity of > 4.0 m/sec, AND aortic valve area of < 1.0 cm2 (or aortic valve area index of < 0.6 cm2/m2).

• Society of Thoracic Surgeons (STS) score of ≥ 8 OR documented heart team agreement of ≥ high risk for aortic valve replacement due to frailty or co-morbidities.
• Symptoms of aortic stenosis, AND New York Heart Association (NYHA) Functional Class II or greater.
• The subject and the treating physician agree that the subject will return for all required post-procedure follow-up visits.

Exclusion Criteria

• Any condition considered a contraindication for placement of a bioprosthetic valve (e.g. subject is indicated for mechanical prosthetic valve).
• A known hypersensitivity or contraindication to any of the following which cannot be adequately pre-medicated:
• aspirin or heparin (HIT/HITTS) and bivalirudin
• ticlopidine and clopidogrel
• Nitinol (titanium or nickel)
• contrast media
• Blood dyscrasias as defined: leukopenia (WBC < 1000 mm3), thrombocytopenia (platelet count <50,000 cells/mm3), history of bleeding diathesis or coagulopathy, or hypercoagulable states.
• Untreated clinically significant coronary artery disease requiring revascularization.
• Severe left ventricular dysfunction with left ventricular ejection fraction (LVEF) < 20% by echocardiography, contrast ventriculography, or radionuclide ventriculography.
• End stage renal disease requiring chronic dialysis or creatinine clearance < 20 cc/min.
• Ongoing sepsis, including active endocarditis.
• Any percutaneous coronary or peripheral interventional procedure with a bare metal or drug eluting stent performed within 30 days prior to study procedure.
• Symptomatic carotid or vertebral artery disease or successful treatment of carotid stenosis within 10 weeks of Heart Team assessment.
• Cardiogenic shock manifested by low cardiac output, vasopressor dependence, or mechanical hemodynamic support.
• Recent (within 6 months of Heart Team assessment) cerebrovascular accident (CVA) or transient ischemic attack (TIA).
• Gastrointestinal (GI) bleeding that would preclude anticoagulation.
• Subject refuses a blood transfusion.
• Severe dementia (resulting in either inability to provide informed consent for the study/procedure, prevents independent lifestyle outside of a chronic care facility, or will fundamentally complicate rehabilitation from the procedure or compliance with follow-up visits).
• Estimated life expectancy of less than 12 months due to associated non-cardiac co-morbid conditions.
• Other medical, social, or psychological conditions that in the opinion of the investigator precludes the subject from appropriate consent or adherence to the protocol required follow-ups exams.
• Currently participating in an investigational drug or another device study (excluding registries).
• Evidence of an acute myocardial infarction ≤ 30 days before the study procedure.
• Need for emergency surgery for any reason.
• Liver failure (Child-Pugh class C).
• Subject is pregnant or breast feeding.

Anatomical exclusion criteria:

• Pre-existing prosthetic heart valve in any position.
• Mixed aortic valve disease (aortic stenosis with severe aortic regurgitation).
• Severe mitral regurgitation.
• Severe tricuspid regurgitation.
• Moderate or severe mitral stenosis.
• Hypertrophic obstructive cardiomyopathy.
• Echocardiographic or Multi-Slice Computed Tomography (MSCT) evidence of intracardiac mass, thrombus, or vegetation.
• Congenital bicuspid or unicuspid valve verified by echocardiography.

For transfemoral or transaxillary (subclavian) access:

• Acce