Evaluation of TAVR Using the NAVITOR Valve in a Global Investigation

Inclusion Criteria: 1. Subject who is judged by a Heart Team, including a cardiac surgeon, to be appropriate for transcatheter heart valve intervention therapy, and is deemed to be at intermediate or low risk for open surgical aortic valve replacement (i.e., heart team estimates risk of surgical mortality \< 7% at 30 days, considering the Society of Thoracic Surgeons (STS) risk score, overall clinical status, and other clinical co-morbidities unmeasured by the risk calculator). \* 2. New York Heart Association (NYHA) Functional Classification of II, III, or IV \* 3. Degenerative aortic valve stenosis with echo-derived criteria, defined as: aortic valve area (AVA) of ≤ 1.0 cm2 (or indexed EOA ≤ 0.6 cm2/m2) AND either mean gradient ≥ 40 mmHg or peak jet velocity ≥ 4.0 m/s or doppler velocity index (DVI) ≤ 0.25. The echocardiogram supporting the qualifying AVA baseline measurement must be performed within 90 days prior to informed consent). \* 4. Aortic annulus diameter of 19-30 mm and ascending aorta diameter of 26-44 mm for the specified valve size listed in the IFU, as measured by CT (systolic phase) conducted within 12 months prior to informed consent. Exclusion Criteria: 1. Life expectancy is less than 2 years in the opinion of the Investigator. 2. Evidence of an acute myocardial infarction \[defined as ST-segment elevation myocardial infarction (STEMI) or non-ST-segment elevation myocardial infarction (NSTEMI) with acute ischemia symptoms and troponin elevation\] within 30 days prior to index procedure. 3. Untreated clinically significant coronary artery disease requiring revascularization. 4. Any percutaneous coronary or peripheral interventional procedure performed within 30 days prior (except pacemaker or implantable cardioverter defibrillator (ICD) implant) to index procedure or planned within 30 days following the index procedure. 5. Blood dyscrasias as defined: leukopenia (WBC \< 3000 mm3), acute anemia (Hb \< 9 g/dL), thrombocytopenia (platelet count \< 50,000 cells/mm³); history of bleeding diathesis or coagulopathy 6. Active peptic ulcer or upper GI bleeding within 3 months prior to index procedure that would preclude anticoagulation 7. Recent (within 6 months prior to index procedure date) cerebrovascular accident (CVA) or a transient ischemic attack (TIA) 8. Renal insufficiency (creatinine \> 3.0 mg/dL or eGFR \< 30 ml/min/1.73m2) and/ or end stage renal disease requiring chronic dialysis 9. Hostile chest or conditions or complications from prior surgery that would make the subject be considered high surgical risk (i.e., mediastinitis, radiation damage, abnormal chest wall, porcelain aorta, adhesion of aorta or internal mammary artery to sternum, etc.) \* 10. Significant frailty as determined by the heart team (after objective assessment of frailty parameters) that would indicate high or extreme surgical risk \* 11. Mixed aortic valve disease (aortic stenosis and aortic regurgitation with predominant aortic regurgitation 3-4+) \* 12. Aortic valve is a congenital unicuspid or congenital bicuspid valve as verified by echocardiography or CT \* 13. Severe ventricular dysfunction with LVEF \< 30% as measured by resting echocardiogram 14. Pre-existing prosthetic heart valve or other implant (such as prosthetic ring or transcatheter edge-to-edge repair (TEER) clip) in any valve position \* (Note: Subjects with a bioprosthetic aortic valve may be included in the ViV cohort.) 15. Severe circumferential mitral annular calcification (MAC) which is continuous with calcium in the left ventricular outflow tract (LVOT) \* 16. Severe (greater than or equal to 3+) mitral regurgitation or severe mitral stenosis with pulmonary compromise 17. Minimum access vessel diameter of \< 5.0 mm for small FlexNav Delivery System and \< 5.5 mm for large FlexNav Delivery System 18. Eccentricity ratio of the annulus \< 0.73 * Criterion not applicable for valve-in-valve application