Antithrombotic Strategy Based on Clinical Events and 4D-CT for Patients After TAVR

Study Overview
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Brief Summary
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This is a multicenter, open-label, randomized controlled study meant to test the superior efficacy of oral anticoagulation (OAC) therapy versus single antiplatelet therapy (SAPT) in patients after TAVR. Patients who accept successful TAVR will be randomized to receive either the OAC group (Vitamin-K antagonists) or the SAPT group (aspirin) for 6 months on a 1:1 ratio. After that, patients from both groups will be treated with single antiplatelet therapy (aspirin). All patients will be followed for 1 year to test the difference between net clinical benefits and bioprosthetic valve thrombosis diagnosed by 4D-CT.

Official Title
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Antithrombotic Strategy Based on Clinical Events and 4D-CT for Patients After TAVR

Conditions
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Transcatheter Aortic Valve Replacement, Antithrombotic Therapy, Bioprosthetic Valve Thrombosis

Intervention / Treatment
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* Drug: Oral anticoagulation therapy
* Drug: Single antiplatelet therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged 18-85 years old with severe aortic stenosis; Successful TAVR via femoral artery approach (VARC 3 device success criteria); Implantation of self-expanding bioprosthetic valve; Be willing to give informed consent. Exclusion Criteria: Patients with anticoagulant indications, such as atrial fibrillation, intracardiac thrombosis, deep vein thrombosis, pulmonary embolism, history of mechanical valve implantation; Patients needed double antiplatelet therapy, such as acute myocardial infarction within one year, coronary stent implantation within 6 months, peripheral artery stent implantation within 3 months; Patients who received concomitant TAVR and percutaneous coronary intervention; Patients with peptic ulcers or active bleeding or history of cerebral hemorrhage Patients with ischemic stroke or TIA within 6 months; Patients with left ventricular ejection fraction < 30% or pulmonary hypertension (>70mmHg) before discharge; Patients intolerant or allergic to aspirin or Vitamin-K antagonists (warfarin); Patients with evaluated glomerular filtration rate <15ml/min/m2 (Cockcroft formula) or on dialysis; Patients with poor compliance, unable to complete the study and follow-up as required; Patients' life expectancy less than 1 year; Patients who already participated in other clinical trials (within the last 30 days).

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Oral anticoagulation therapy group<br>Vitamin-K antagonists (warfarin), therapeutic INR: 1.8-2.5 | Drug: Oral anticoagulation therapy<br>* Vitamin-K antagonists (warfarin)<br>|
| Active Comparator: Single antiplatelet therapy group<br>Aspirin, 75-100mg | Drug: Single antiplatelet therapy<br>* Aspirin<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| A composite of all-cause mortality, myocardial infarction, stroke, TIA, peripheral artery thrombosis, intracardiac thrombosis, major bleeding (BARC 3a), and disabling/life-threatening bleeding (BARC 3b,3c,5) | A composite of all-cause mortality, myocardial infarction, stroke, TIA, peripheral artery thrombosis, intracardiac thrombosis, major bleeding (BARC 3a), and disabling/life-threatening bleeding (BARC 3b,3c,5) | 1 year | 
| Rates of bioprosthetic valve thrombosis detected by 4D-CT |  | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| A composite of all-cause mortality, myocardial infarction, stroke, TIA, peripheral artery thrombosis, intracardiac thrombosis | A composite of all-cause mortality, myocardial infarction, stroke, TIA, peripheral artery thrombosis, intracardiac thrombosis | 1 year | 
| Major bleeding (BARC 3a), and disabling/life-threatening bleeding (BARC 3b,3c,5) | Major bleeding (BARC 3a), and disabling/life-threatening bleeding (BARC 3b,3c,5) | 1 year | 
| Cardiac death | Cardiac death | 1 year | 
| Minor bleeding (BRAC 2) | Minor bleeding (BRAC 2) | 1 year | 
| Bleeding (BRAC 1, 2, 3a-c, 5) | Bleeding (BRAC 1, 2, 3a-c, 5) | 1 year | 
| All-cause mortality | All-cause mortality | 1 year | 
| Myocardial infarction | Myocardial infarction | 1 year | 
| Stroke | Stroke | 1 year | 
| TIA | TIA | 1 year | 
| Peripheral artery thrombosis | Peripheral artery thrombosis | 1 year | 
| Intracardiac thrombosis | Intracardiac thrombosis | 1 year | 
| Major bleeding (BARC 3a) | Major bleeding (BARC 3a) | 1 year | 
| Disabling/life-threatening bleeding (BARC 3b,3c,5) | Disabling/life-threatening bleeding (BARC 3b,3c,5) | 1 year |