VitaFlow® Transcatheter Aortic Valve Replacement System Pre-market Trial Long Term Follow Up （VITAL）

Inclusion Criteria: * Must meet 1, 2, 3, 4 or 1, 5 to be selected: 1. Patients who have participated in the VitaFlow® transcatheter aortic valve system pre-market trial in the 4 designated research institutions\*; 2. Be able to get in touch with the patient or his legal guardian/relative; 3. Patients who can understand the purpose and nature of the follow-up of this study, and are willing to cooperate with the follow-up and provide follow-up information; 4. Sign the informed consent form; 5. Patients who are known to have died. * 4 research institutions: Zhongshan Hospital Fudan University, Second Affiliated Hospital of Zhejiang University School of Medicine, West China Hospital of Sichuan University and Fuwai Hospital. Exclusion Criteria: 1. Participate in clinical trials of other drugs or medical devices and have not yet reached the primary endpoint; 2. The investigator judges that the patient's compliance is poor and the study cannot be completed as required.