Safety and Efficacy of Emergent TAVI in Patients With Severe AS

Study Overview
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Brief Summary
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This is a single-centre, prospective, observational cohort study focusing on of patients suffering severe aortic valve stenosis (AS) undergoing emergent transcatheter aortic valve implantation (TAVI). AS patients undergoing emergent TAVI always have complicated clinical situations. Therefore, the aims of the study are to collect the incidence and outcomes of emergent TAVI in patients with severe symptomatic AS, to assess the safety and effectiveness of emergency TAVI system for severe AS, and to describe a more practical evidence of emergency TAVI system in severe AS patients.

Official Title
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Safety and Efficacy of Emergent Transcatheter Aortic Valve Implantation (TAVI) in Patients With Severe Aortic Valve Stenosis (AS): a Single-center, Prospective, Observational Cohort Study.

Conditions
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Aortic Valve Stenosis, Transcatheter Aortic Valve Implantation, Emergencies

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Every patient that diagnosed with severe aortic valve stenosis (evaluated by echocardiography: peak transaortic valve blood flow rate ≥4.0m/s, or mean transaortic valve pressure gradient ≥40mmHg (≥5.32kPa), or aortic Valve area <0.8cm2, or AVA<0.5cm2/m2); Every patient that 1) required cardiopulmonary resuscitation due to cardiac arrest, or requiring external chest compressions during surgery (Salvage), 2) or has ongoing, refractory (difficult, complicated, and/or unmanageable) unrelenting cardiac compromise, with or without hemodynamic instability, and not responsive to any form of therapy except cardiac surgery (STS/ACC TVT defined Urgent Status), 3) or required urgent procedure during same hospitalization in order to minimize chance of further clinical deterioration (examples include, but are not limited to, worsening, sudden chest pain, heart failure, acute myocardial infarction, anatomy, intra-aortic balloon pump, unstable angina with intravenous nitroglycerin or rest angina) (STS/ACC TVT defined Urgent Status); Every patient that has been informed of the objectives of the study, agreed to participate, has signed the approved consent form, and was willing to accept all relevant examinations and clinical follow-up. Exclusion Criteria: Anatomically, the approach or aortic root is not suitable for transcatheter aortic valve implantation (TAVI). Anatomical morphology or vascular diseases affecting the device approach. Left ventricular outflow tract obstruction. Primary dilated cardiomyopathy. The echocardiogram indicates the presence of left ventricular thrombus. Cannot tolerate anticoagulation and antiplatelet therapy. Are allergic or resistant to nickel titanium alloys. Active infective endocarditis, or other active infections affecting the effect of TAVI. Severe disabling Alzheimer's disease. Life expectancy< 6 months. Other conditions (examples include poor compliance of patients and families) considered by the investigator to be inappropriate for participation in this clinical trial.
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| All-cause mortality | including cardiac and non-cardiac deaths. | 12 months post-TAVI | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of major adverse cardiovascular and cerebrovascular events (MACCEs) during the trial | Incidence of MACCEs (including mortality, disabling stroke, myocardial infarction, reoperation, arrhythmias and conduction blocks) during the trial. | immediate, 30 days, 6 months, 12 months, 2 years, 3 years, 4 years and 5 years post-TAVI | 
| Acute kidney injury | Incidence of acute kidney injury (kidney function was accessed by AKIN kidney function classification, including AKIN class II, AKIN class III and renal replacement therapy (RRT: hemodialysis, peritoneal dialysis, hemofiltration) ). | immediate, 30 days, 6 months, 12 months, 2 years, 3 years, 4 years and 5 years post-TAVI | 
| Permanent pacemaker implantation | Rate of patients implanted with permanent pacemaker. | immediate, 30 days, 6 months, 12 months, 2 years, 3 years, 4 years and 5 years post-TAVI | 
| Vascular complications (life-threatening or disabling) | including dissection, occlusion, rupture and bleeding of access vessels. | immediate, 30 days, 6 months, 12 months, 2 years, 3 years, 4 years and 5 years post-TAVI | 
| The incidence of other TAVI complications | including conversion to surgery, unexpected cardiopulmonary mechanical assistance, coronary artery occlusion, ventricular septal perforation, mitral valve injury or loss of function, pericardial tamponade, endocarditis, valve thrombosis, valve ectopic (displacement, embolization, misrelease), valve-in-valve, reoperation due to valve dysfunction, and so on. | immediate, 30 days, 6 months, 12 months, 2 years, 3 years, 4 years and 5 years post-TAVI | 
| Valve function | Doppler echocardiography was used to evaluate the valve performance at each follow-up point, including valve orifice area, mean aortic gradient, degree of valve regurgitation, moderate or above perivalvular leakage (PVL), and degree of aortic stenosis. | immediate, 30 days, 6 months, 12 months, 2 years, 3 years, 4 years and 5 years post-TAVI | 
| Cardiac function improvement | Doppler echocardiography was used to evaluate the heart function at each follow-up point, and cardiac function improvement is accessed by NYHA cardiac function classification, including NYHA class I, II, III and IV. | immediate, 30 days, 6 months, 12 months, 2 years, 3 years, 4 years and 5 years post-TAVI | 
| Device success rate | Incidence of device success | immediate post-TAVI |