Non-antithrombotic Therapy After Transcatheter Aortic Valve Implantation Trial

Study Overview
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Brief Summary
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Aspirin group: Aspirin 100mg will be started within 24 hours after randomization, and continued aspirin 100mg/day the end of the study period. Non-antithrombotic group: No antithrombotic agents will be administered after randomization until the end of the study period.

Official Title
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Non-antithrombotic Therapy After Transcatheter Aortic Valve Implantation Trial

Conditions
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Aortic Stenosis, TAVI(Transcatheter Aortic Valve Implantation), Aspirin, DAPT(Dual Antiplatelet Therapy), SAPT(Single Antiplatelet Therapy)

Intervention / Treatment
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* Drug: Aspirin group
* Drug: Non-antithrombotic group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who underwent transfemoral TAVI for aortic stenosis Patients aged 20 years or older at the time of informed consent Patients who have a thorough understanding of the subject of the study and who have agreed in writing to participate in the study Exclusion Criteria: Those with perioperative complications at the time of TAVI (conversion to open heart surgery, coronary artery occlusion, annulus rupture, cardiac tamponade, vascular dissection, cerebral infarction/cerebral hemorrhage, new atrial fibrillation, new atrioventricular block) Individuals requiring antiplatelet agents for reasons other than TAVI (history of myocardial infraction, history of PCI（Percutaneous Coronary Intervention）, history of EVT（EndoVascular Treatment）, history of cerebral infraction and transient ischaemic stroke, with significant coronary artery narrowing, with high-grade carotid artery narrowing, and others judged as requiring antiplatelet therapy by the chief researcher or a sub-investigator) Patients requiring oral anticoagulants (patients with atrial fibrillation, history of pulmonary embolism or deep venous thrombosis, and other patients who are deemed to require anticoagulation therapy by the investigator or coinvestigator) Patients with eGFR（estimated Glomerular Filtration Rate） <30 and patients on hemodialysis/peritoneal dialysis. Patients with a history of valve replacement in the heart valves. Patients who are pregnant, have childbearing potential, wish to become pregnant, or are breastfeeding. Patients who have a concomitant medical illness associated with expected survival less than one year. Patients who have the contraindications for aspirin. Patients with a diagnosis of severe allergy to aspirin or a history of hypersensitivity. Patients requiring a legally acceptable representative, patients unable to obtain written informed consent, or patients unable to understand the outline or purpose of the study. Other patients for whom the principal investigator or the coinvestigator judges the participation in the study inappropriate.

Ages Eligible for Study
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Minimum Age: 20 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>Aspirin 100mg will be started within 24 hours after randomization, and continued aspirin 100mg/day the end of the study period. | Drug: Aspirin group<br>* Aspirin 100mg will be started within 24 hours after randomization, and continued aspirin 100mg/day the end of the study period.<br>|
| Experimental: Non-antithrombotic group<br>No antithrombotic agents will be administered after randomization until the end of the study period. | Drug: Non-antithrombotic group<br>* No antithrombotic agents will be administered after randomization until the end of the study period.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Primary endpoint | Composite endpoint consisting of all-cause deaths, myocardial infarction, stroke from any cause and bleeding from randomization to end of study The outcomes of this study will comply with the Valve Academic Research Consortium 3 (VARC 3). VARC 3 Type 1, Type 2, Type 3, and Type 4 bleeding are all included as bleeding. In this study, the study subjects will be randomized after it has been confirmed that there were no perioperative complications, so it is essentially assumed that there will be no procedure-related bleeding. Surviving subjects for whom the event does not occur will be censored as of the date the study treatment is discontinued or as of the last confirmed date of survival. | minimum 1 year, maximum 3 years of follow-up | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Key Secondary endpoint | Bleeding Events from Randomization to Study End. Cardiovascular adverse events from randomization until the end of the study (composite endpoint comprised of cardiovascular death, myocardial infarction, or CVA). The definition of censoring for survival time analysis is the same as that used for the primary endpoint. | minimum 1 year, maximum 3 years of follow-up |