safety and efficacy of taurusone® transcatheter aortic valve system in patients with severe calcific aortic stenosis

Conditions: Aortic Stenosis

Summary: to observe and evaluate the safety and efficacy of taurusone® transcatheter aortic valve system in patients with severe calcific aortic stenosis through a prospective, multicenter clinical trial using objective performance criteria.


Eligibility criteria:
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; * previous endocarditis or active endocarditis; * acute myocardial infarction (q-wave mi, or non-q-wave mi with elevated creatine kinase isoenzyme and troponin t) within 30 days; * any intracardiac mass, left ventricular or atrial thrombus, vegetation on echocardiography; * symptomatic atrial fibrillation that cannot be improved by drug therapy; * familial hypertrophic cardiomyopathy; * mitral or tricuspid valve insufficiency (grade ii regurgitation or higher); * previous aortic valve graft (mechanical or bioprosthetic valve); * known allergies to contrast agents, aspirin, heparin, ticlopidine drugs, nitinol shape memory alloy, or bovine products; * known contraindications or allergies to anticoagulant regimens, or inability to use anticoagulants throughout the trial; * other serious diseases that may reduce life expectancy to less than 12 months (such as clinically recurrent or metastatic cancer, congestive heart failure, etc.); * current substance abuse problems (e.g., alcohol, cocaine, heroin, etc.); * scheduled to undergo surgery that may result in protocol noncompliance or confounding in data interpretation. * cerebrovascular accident (cva) in the past 6 months; * patients with common carotid artery or internal carotid artery or vertebral artery stenosis (\>70%); * white blood cell count \<3×109/l, platelet count \<50×109/l; * hemoglobin \< 90 g/l; * patients with severe coagulopathy; * severe left ventricular dysfunction, left ventricular ejection fraction \< 20%; * abdominal or thoracic aortic aneurysm; * hepatic encephalopathy or acute active hepatitis; * on dialysis or baseline creatinine level \> 2.5 mg/dl (221 μ mol/l); * bleeding tendency or history of coagulation disease or refusal of blood transfusion; * patients with active peptic ulcer or active gastrointestinal (gi) bleeding; * patients with neurological diseases that seriously affect mobility and activities of daily living; * patients with mental illness or psychological disorders who are unable to communicate effectively; * patients who need emergency surgery for any reason; * patients who have participated in other drug or medical device clinical trials within 3 months prior to screening; * other conditions that make the patient ineligible to participate in this clinical trial in judgement of investigators