Alwide Plus China Post-market Clinical Investigation

Inclusion Criteria: * Age≥18 years old; * Severe aortic stenosis verified by echocardiogram: mean transvalvular gradient≥40mmHg (1mmHg=0.133kPa), or peak aortic jet velocity≥4m/s, or aortic valve area (AVA) ≤ 1.0cm2 (or AVA index≤ 0.6cm2/m2); * Patients, who can understand the clinical investigation purpose, voluntary agree and sign the informed consent form, and willing to comply with relevant trial assessments and clinical follow up Exclusion Criteria: * Aortic valve anatomy or lesion unsuitable or not necessary for balloon pre-dilation during the TAVR procedure * TAVR procedure in trans-apical access * Pre-implanted mechanical or bioprosthetic valve at the aortic valve position * Acute myocardial infarction (MI) occurred in the last 30 days before the treatment； * LVOT obstruction; * Serious left ventricular dysfunction with left ventricular ejection fraction (LVEF) \<20% * Echocardiographic evidence of intracardiac mass, thrombus or neoplasm； * Unable to receive anticoagulation or antiplatelet therapy； * Allergy to nitinol or sensitive contrast media； * Active bacterial endocarditis or other active infection may affect the procedure； * Aortic valve anatomy , lesion, or other situation unsuitable for the prosthesis valve implantation as assessed by the investigator team； * Life expectancy \> 12 months； * vulnerable individuals who are unable to give informed consent/ unable to fully understand all aspects of the investigation or Severe incapacitating Alzheimer's disease； * Patients who participated in other clinic trials of drugs or medical device before being enrolled for which the primary endpoint follow up duration has not been reached； * Investigators determined that patients have poor compliance and can't complete the study as required