Aspirin vs Clopidogrel After TAVR

Study Overview
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Brief Summary
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Currently, the optimal antithrombotic therapy after transcatheter aortic valve replacement (TAVR) remains still unknown., The purpose of the study is to compare aspirin versus clopidogrel monoantiplatelet therapy for preventive effect on leaflet thrombosis in patients undergoing TAVR for severe aortic stenosis. This study is designed as a prospective, multicenter, open label, randomized controlled study. Eligible patients will be randomized to aspirin or clopidogrel monotherapy after TAVR. Patients will have dual antiplatelet therapy of aspirin 100 mg and clopidogrel 75 mg for 4 weeks after TAVR and then subsequent monoantiplatelet therapy of either aspirin 100 mg or clopidogrel 75 mg according to the randomization. Leaflet thrombosis will be assessed with cardiac computed tomography (CT) and transthoracic echocardiography at 3 months after TAVR. Patients will be clinically followed for 6 months. The primary endpoint is the Incidence of leaflet thrombosis on cardiac CT at 3 months.

Detailed Description
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Prospective, multicenter, open label, randomized controlled study Eligible patients will be randomized to aspirin or clopidogrel monotherapy after TAVR All patients will have dual antiplatelet therapy of aspirin 100 mg and clopidogrel 75 mg for 4 weeks after TAVR and then subsequent monoantiplatelet therapy of either aspirin 100 mg or clopidogrel 75 mg. Leaflet thrombosis will be assessed with cardiac computed tomography (CT) and transthoracic echocardiography at 3 months after TAVR Clinical follow-up up to 6 months

Official Title
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Aspirin Versus Clopidogrel for Leaflet Thrombosis Prevention in Patients Undergoing Transcatheter Aortic Valve Replacement: ACLO-TAVR Trial

Conditions
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Severe Aortic Stenosis

Intervention / Treatment
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* Drug: Aspirin single antiplatelet therapy
* Drug: Clopidogrel single antiplatelet therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients >19 years old Patients who underwent TAVR symptomatic severe AS Provision of informed consent Exclusion Criteria: Patients requiring dual antiplatelet therapy longer than 4 weeks Any conditions requiring specific antiplatelet therapy aspirin or clopidogrel History of stroke or transient ischemic attack (TIA) within 6 months Planned major surgery Cardiogenic shock or hemodynamic instability Chronic kidney disease stage 4 or 5 (eGFR <30mL/min) Valve-in-valve TAVR procedure Hypersensitivity or contraindication to aspirin or clopidogrel Indication for anticoagulation therapy

Ages Eligible for Study
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Minimum Age: 19 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 |
| --- | --- |
| Active Comparator: Aspirin group<br>Patients receive the aspirin (100 mg/day) single antiplatelet therapy after 4 weeks of dual antiplatelet therapy of aspirin (100 mg/day) and clopidogrel (75 mg/day) after TAVR. | Drug: Aspirin single antiplatelet therapy<br>* Patients receive the aspirin (100 mg/day) single antiplatelet therapy after 4 weeks of dual antiplatelet therapy of aspirin (100 mg/day) and clopidogrel (75 mg/day) after TAVR.<br>|
| Experimental: Clopidogrel group<br>Patients receive the clopidogrel (75 mg/day) single antiplatelet therapy after 4 weeks of dual antiplatelet therapy of aspirin (100 mg/day) and clopidogrel (75 mg/day) after TAVR. | Drug: Clopidogrel single antiplatelet therapy<br>* Patients receive the clopidogrel (75 mg/day) single antiplatelet therapy after 4 weeks of dual antiplatelet therapy of aspirin (100 mg/day) and clopidogrel (75 mg/day) after TAVR.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of leaflet thrombosis | Incidence of leaflet thrombosis on cardiac CT at 3 months after TAVR | At 3 months after TAVR | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Any stroke |  | 3 months and 6 months after TAVR | 
| Ischemic Stroke |  | 3 months and 6 months after TAVR | 
| Transient ischemic attack |  | 3 months and 6 months after TAVR | 
| Thromboembolic events (composite of any stroke, myocardial infarction, systemic embolism (not involving the central nervous system), deep-vein thrombosis, or pulmonary embolism) |  | 3 months and 6 months after TAVR | 
| Echocardiographic parameters (maximum and mean aortic valve pressure gradient) |  | at 3 months after TAVR | 
| Echocardiographic parameters (doppler velocity index) |  | at 3 months after TAVR | 
| Echocardiographic parameters (paravalvular regurgitation) |  | at 3 months after TAVR | 
| Echocardiographic parameters (leaflet thrombosis) |  | at 3 months after TAVR | 
| VARC-3 type 3 or 4 bleeding |  | 3 months and 6 months after TAVR | 
| VARC-3 type 2 bleeding |  | 3 months and 6 months after TAVR |