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.
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
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.