Inclusion Criteria:

1. Age≥ 70 years;
2. Patients with symptomatic severe aortic stenosis (mean pressure gradient across the aortic valve ≥ 40 mmHg (1 mmHg = 0.133 kPa) on echocardiography, or trans-aortic valve blood flow velocity ≥ 4.0 m/s, or aortic orifice area ≤ 1.0 cm2, or effective aortic orifice area index ≤0.6 cm2/m2)
3. NYHA Grading ≥ Level II;
4. Life expectancy of more than 1 year after implantation of the prosthetic valve;
5. Assessed by not less than two cardiothoracic surgeons, documented as a contraindication to surgery, or documented as unsuitable for conventional surgery;
6. Patients who can understand the purpose of the trial, voluntarily participate in and sign the informed consent form, and are willing to undergo relevant examinations and clinical follow-up.

Exclusion Criteria:

1. The imaging data shows that it is anatomically unsuitable for transcatheter aortic valve implantation;
2. Acute myocardial infarction (defined as Q-wave myocardial infarction, or non-Q-wave myocardial infarction with CK-MB≥ twice normal and/or elevated Tn (WHO definition)) occurring within 1 month before valve implantation);
3. Received any therapeutic traumatic cardiac surgery (other than coronary revascularization) within 1 month before valve implantation;
4. Implanted prosthetic heart valves at any location, or combined with other valves with severe stenosis or severe regurgitation;
5. Hemorrhagic constitution or coagulation dysfunction (platelet PLT<50×10^9/L);
6. Haemodynamic instability requiring continuous mechanical cardiac assistance;
7. Severe left ventricular dysfunction, left ventricular ejection fraction LVEF <20%;
8. Echocardiography shows intracardiac thrombosis or vegetation, etc.;
9. Renal insufficiency decompensation (endogenous creatinine clearance rate<20ml/min);
10. Active peptic ulcer or upper gastrointestinal bleeding within 3 months;
11. Cerebrovascular events (CVAs) within 3 months before valve implantation, excluding transient ischemic attack;
12. Allergy or contraindication to antiplatelet drugs, anticoagulant drugs, or contrast agents, resulting in the inability to perform preoperative or appropriate intraoperative medication, allergies, or contraindications to polymer materials;
13. Patients with active infective endocarditis or other active infections;
14. Concurrent participation in other drug or device studies.
15. In the opinion of the investigator, it is not suitable for enrollment.