The TaurusOne® transcatheter aortic valve system with retrievable delivery catheter system is evaluated the safety and effectiveness for the delivery of artificial aortic valve in a prospective, multicenter, single-arm clinical trial.

The TaurusOne® transcatheter aortic valve system with retrievable delivery catheter system is evaluated the safety and effectiveness for the delivery of artificial aortic valve in a prospective, multicenter, single-arm clinical trial. According to the inclusion and exclusion criteria, sixty patients are planed been enrolled and implanted with TaurusOne® .Patients are seen at pre and post procedure, discharge, 30 days. The main follow-up included clinical symptoms and signs, cardiac ultrasound, CT, etc. The outcome included immediate device success, procedure success, And the major cardiovascular and cerebrovascular adverse events (MACCE, including mortality, stroke, myocardial infarction, reoperation, arrhythmia, conduction block).

Inclusion Criteria:

• Patients who are willing to participate and sign the informed consent and can cooperate with the whole trial process;
• Age ≥70 years old;
• Patients with severe calcified aortic stenosis confirmed by echocardiography (trans-aortic valve flow velocity ≥ 4.0m /s, or trans-active valvular pressure difference ≥40mmHg (1mmHg=0.133kPa), or aortic valve orientation area < 0.8cm2, or effective aortic valve orifice the product index is < 0.5cm2/m2);
• Appear obvious symptoms caused by aortic stenosis, NYHA class Ⅱ or higher;
• The cardiac team (at least two specialists in cardiovascular surgery) assessed the patient as unsuitable for routine surgery ;
• The life expectancy of the patient after implantation of the prosthetic valve was evaluated by the cardiac team (at least two specialists in cardiovascular surgery) as more than one year;
• Patients with aortic ring diameter ≥18mm and ≤29mm (cardiac CT measurement);
• The diameter of the ascending aorta of the patient was < 50mm.

Exclusion Criteria:

• Patients with bacteremia or toxemia;
• previous history or active endocarditis;
• Acute myocardial infarction (Q-wave MI, or non-Q-wave MI with increased creatine kinase isoenzyme and/or troponin T) within 30 days;
• Echocardiography found any intracardiac mass, left ventricle or atrial thrombosis, vegetations;
• Symptomatic atrial fibrillation that cannot be improved by medication;
• Familial hypertrophic cardiomyopathy;
• Mitral valve and tricuspid valve insufficiency (reflux Ⅱ level above);
• Prior aortic valve grafts (mechanical or biological valve stents);
• Known allergy to contrast agent, aspirin, heparin, ticlopidine, nickel-titanium memory alloy, or bovine products;
• Known to be contraindication or allergic to all anticoagulant regimens, or unable to use anticoagulant during the test;
• Other serious diseases that may reduce life expectancy to less than 12 months (e.g. clinically recurrent or metastatic cancer, congestive heart failure, etc.)
• Current drug abuse problem (e.g., alcohol, cocaine, heroin, etc.); Plan to undergo surgery that may cause nonadherence to protocol or confusion in data interpretation.
• Cerebrovascular accident (CVA) in the past 6 months;
• Patients with common or internal carotid or vertebral artery stenosis (> 70%);
• WBC count < 3×109/L, platelet count < 50×109/ L;
• Hemoglobin < 90g/L;
• Patients with severe coagulation dysfunction;
• Severe left ventricular dysfunction, left ventricular ejection fraction < 20%;
• Abdominal or thoracic aortic aneurysm;
• Hepatic encephalopathy or acute active hepatitis;
• Receiving dialysis or a baseline creatinine level of > 3.0 mg/dL (266μmol/L);
• Have bleeding tendency or history of coagulation disease or refuse blood transfusion;
• Have active gastric ulcer or active gastrointestinal (GI) bleeding;
• Suffer from neurological diseases that seriously affect the ability to move or live in daily life;
• People with mental illness or mental disorder who cannot express themselves normally;
• Need emergency surgery for any reason;
• Screening participants who had participated in other drug or medical device clinical trials within the previous 3 months;
• Other conditions considered by the investigator to be inappropriate for participation in this clinical trial.