CoreValve Advance International Post Market Study

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