The CoreValve Advance study is intended to evaluate the clinical utility of the Medtronic CoreValve System in a "Real-World" patient population.

The CoreValve Advance study is intended to evaluate the clinical utility of the Medtronic CoreValve System for percutaneous aortic valve implantation in a "Real-World" patient population with severe aortic valve stenosis. Data collected in this study will provide additional information on the understanding of the safety and device performance and how to best treat elderly patients with severe aortic valve stenosis. In addition, health economic data will be collected to understand the improvement of quality of life and the cost effectiveness of the therapy.

Inclusion Criteria:

• Patients with severe aortic valve stenosis requiring treatment
• Patient is an acceptable candidate for elective treatment with the Medtronic CoreValve System and in conformity with the local regulatory and medico economical context
• Patient is above the minimum age as required by local regulations to be participating in a clinical study
• The patient or legal representative has been informed of the nature of the study and has consented to participate, and has authorized the collection and release of his/her medical information by signing a consent form ("Patient Informed Consent Form")

Exclusion Criteria:

• Currently participating in another trial
• High probability of non-adherence to the follow-up requirements (due to social, psychological or medical reasons)
• Pregnancy

patients with severe aortic valve stenosis requiring treatment, who are selected to be treated electively with the Medtronic CoreValve System