Safety and Efficacy of TaurusOne® Transcatheter Aortic Valve System in Patients With Severe Calcific Aortic Stenosis

Inclusion Criteria: * Patients who voluntarily participate and sign the informed consent and are able to comply with the entire trial process; * Age ≥ 70 years; * Patients with severe calcific aortic stenosis confirmed by echocardiography (Transaortic flow velocity ≥ 4.0 m/s, or aortic-valve gradient ≥ 40 mmHg (1 mmHg = 0.133 kPa), or aortic valve area \< 0.8 cm2, or effective orifice area \< 0.5 cm2/m2); * Patients who have symptoms obviously caused by aortic stenosis, NYHA Class II or worse; * Patients who are unsuitable for conventional surgery evaluated by the cardiac team (including at least two cardiovascular surgeons) \[13\] \*; * Life expectancy after implantation of prosthetic valve is more than one year evaluated by the cardiac team (including at least two cardiac surgeons); * Aortic annulus diameter ≥ 18 mm and ≤ 29 mm (measured by cardiac CT); * Ascending aorta diameter \< 50 mm \*: If the patient meets any of the following criteria judged by a multidisciplinary cardiac team composed of cardiologists and cardiovascular surgeons, radiologists, anesthesiologists, etc. (at least two cardiovascular surgeons), the patient will be identified as unsuitable for conventional surgery (at least STS ≥ 8 points): * Estimated risk of surgery-related death or disability \> 50% within 1 year; * ≥3 major organ damage that could not be improved by surgery; * Obstacles related to surgical procedures judged as serious Exclusion Criteria: * Patients with bacteremia or toxemia; *…