The goal of this clinical trial is to verify that Non-Antithrombotic Therapy (NAPT) followed by Oral Anticoagulants (OAC) monotherapy for 45 days after Left Atrial Appendage Closure (LAAC) is non-inferior to Single Antiplatelet Therapy (SAPT) with aspirin during the period from randomization to the end of observational period (4 years at the maximum) in non-valvular atrial fibrillation subjects with high bleeding risk.
The primary endpoint is a composite endpoint consisting of all-cause mortality, myocardial infarction, stroke, systemic embolism, major bleeding, or clinically relevant non-fatal bleeding from randomization to the end of study observation (up to a maximum follow-up of 4 years).
* Participants will be enrolled in this study until the day following the implementation of LAAC and will be randomized to the SAPT arm and NAPT arm in a 1:1 ratio. * Participants will be observed for 4 years from the time the first subject is enrolled in this study. * Participants will visit the hospital at 45 days, 1 year, and 2 years after enrollment, and will also be followed up by telephone, basically at the end of the observation period (up to a maximum follow-up of 4 years).
\<Study treatment duration\> In both arms, OAC monotherapy will be initiated in the first 24 hours of enrollment and continued for 45 days (allowed window period: plus 2 weeks)..
* SAPT arm will continue to receive 45 days of OAC monotherapy followed by low-dose aspirin (75～100 mg/day) as an antithrombotic agent required through the end of the study observation period. * NAPT arm do not receive antithrombotic medication after 45 days of OAC monotherapy through the end of the study observation period.
Patient has documented non-valvular atrial fibrillation (i.e, atrial fibrillation without severe mitral stenosis or mechanical valves)
Patient has CHA2DS2-VA score of 2 or greater
Patient meets the guidelines for proper use of the left atrial appendage closure system including patient who has an increased risk of bleeding.
Individual with nonvalvular atrial fibrillation who underwent successful LAAC (defined as no significant residual circumferential leak [>3 mm] or major morbidity by the time of procedure completion).
Patients who are currently enrolled in other clinical trials, except when the patient is participating in a mandatory governmental registries or purely observational registries with no associated treatment.
Individuals require long-term anticoagulation therapy for reasons other than atrial fibrillation (AF)-related stroke risk reduction (e.g.,thrombophilic conditions, previous pulmonary embolism, or deep venous thrombosis).
Patients requiring oral antiplatelet therapy for reasons other than LAAC (e.g.,history of myocardial infarction, history of endovascular treatment, history of stroke/transient ischemic attack, significant coronary stenosis proven by myocardial ischemia, severe carotid stenosis requiring invasive treatment,hematologic disease such as antiphospholipid syndrome or if the investigator and/or subinvestigator judged the need for antiplatelet therapy).
Patients who meet one or more of the following criteria
OCEAN-SHD Study Group
Lead sponsor
Boston Scientific Corporation
Collaborator