DEFLECT II: A Study to Evaluate the Safety and Performance of the TriGuard™HDH in Patients Undergoing TAVR

Inclusion Criteria: 1. The patient must be ≥ 18 years of age. 2. The patient meets indications for transcatheter aortic valve replacement procedure. 3. The patient is willing to comply with specified follow-up evaluations. 4. The patient, or legally authorized representative, has been informed of the nature of the study, agrees to its provisions and has been provided written informed consent, approved by the appropriate Medical Ethics Committee (EC). Exclusion Criteria: 1. Patients undergoing transcatheter aortic valve replacement via the trans-axillary, subclavian, or direct aortic route 2. Pregnant or nursing subjects and those who plan pregnancy in the period up to 1 year following index procedure. Female subjects of child-bearing potential must have a negative pregnancy test done within 7 days prior to index procedure per site standard test. 3. Patients with known diagnosis of acute myocardial infarction (AMI) within 72 hours preceding the index procedure (according to definition) or AMI \> 72 hours preceding the index procedure and creatine kinase and creatine kinase fraction have not returned to normal limits at the time of procedure. 4. Patients who are currently experiencing clinical symptoms consistent with new onset AMI, such as nitrate-unresponsive prolonged chest pain. 5. Patients with impaired renal function (estimated Glomerular Filtration Rate \[Estimated Glomerular Filtration Rate\] \<30, calculated from serum creatinine by the Cockcroft-Gault formula). 6. Patients with torturous/unsuitable anatomy as related to major cerebral arteries in the aortic arch that may interfere with device deployment or remain deployed. 7. Patients with a platelet count \<100.000 cells/mm³ or \>700.000 cells/mm³ or a white blood cell \<3000 cells/mm³ within 7 days prior to index procedure. 8. Patients with a history of bleeding diathesis or coagulopathy or patients in whom anti-platelet and/or anticoagulant therapy is contraindicated, or will refuse transfusion. 9. Patients who have received any organ transplant or are on a waiting list for any organ transplant. 10. Poor fluoroscopic visualization due to obesity or other medical reason 11. Hypotension requiring iv/ia medication or other therapy such as resuscitation and defibrillation 12. Patients with known other medical illness or known history of substance abuse that may cause non-compliance with the protocol, confound the data interpretation or is associated with a life expectancy of less than one year. 13. Patients with a known hypersensitivity or contraindication to aspirin, heparin/bivalirudin, clopidogrel/ticlopidine, nitinol, stainless steel alloy, latex, and/or contrast sensitivity that cannot be adequately pre-medicated. 14. Patients with a history of a stroke or transient ischemic attack (TIA) within the prior 6 months. 15. Patients with an active peptic ulcer or upper gastrointestinal (GI) bleeding within the prior 6 months. 16. Patients presenting with cardiogenic shock. 17. Patients with severe peripheral arterial disease that precludes the delivery sheath vascular access. 18. Patients with severe calcification/atheroma, friable or mobile atherosclerotic plaque in the aortic arch 19. Patients with contraindication to cerebral MRI. 20. Patients going through unprotected (cerebral embolization) cardiovascular procedure prior, during or post transcatheter aortic valve replacement procedure, before the post-procedure diffusion-weighted magnetic resonance imaging evaluation 21. Patients who have a planned treatment with any other investigational device or procedure during the study period.