Non-Antithrombotic Versus Single Antiplatelet Therapy Following Left Atrial Appendage Closure: NAPT-LAAC Randomized Controlled Trial
Led by OCEAN-SHD Study Group · Updated on 2025-08-15
500
Participants Needed
21
Research Sites
43 weeks
Total Duration
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AI-Summary
Brief Title
Who Can Participate
AI-Screening
Your Study Journey
Trial Site Locations
Research Team
How is the study designed?
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Frequently Asked Questions
Research Publications
Sponsors
O
OCEAN-SHD Study Group
Lead Sponsor
B
Boston Scientific Corporation
Collaborating Sponsor
AI-Summary
What this Trial Is About
Researchers are evaluating two different approaches to antithrombotic therapy after Left Atrial Appendage Closure (LAAC) in people with non-valvular atrial fibrillation who have a high risk of bleeding. The study compares Non-Antithrombotic Therapy (NAPT) followed by oral anticoagulants (OAC) monotherapy for 45 days against Single Antiplatelet Therapy (SAPT) with aspirin. This Phase 4 trial aims to determine if the NAPT approach is not worse than SAPT over an observation period of up to 4 years, focusing on a combination of serious events including death, heart attack, stroke, embolism, and bleeding complications.
Participants are randomly assigned to one of two groups: the SAPT arm or the NAPT arm, with equal chance of assignment. Both groups start with oral anticoagulants for 45 days after LAAC. After this period, the SAPT group continues with low-dose aspirin, while the NAPT group does not receive further antithrombotic medication for the remainder of the study. The study includes visits at 45 days, 1 year, and 2 years after enrollment, along with telephone follow-ups up to 4 years.
During their participation, subjects will undergo clinical evaluations to monitor safety and effectiveness, including imaging tests to check for device-related thrombus at specific intervals. Researchers will track major health events such as mortality, heart attacks, strokes, embolism, and bleeding incidents throughout the study. The study includes regular hospital visits, phone assessments, and ongoing observation, lasting up to 4 years per participant to thoroughly assess long-term outcomes.
CONDITIONS
Brief Title
Non-antithrombotic Versus. Single Antiplatelet Therapy Following Left Atrial Appendage Closure
Who Can Participate
All Genders
Eligibility Criteria
You may qualify if you...
Documented non-valvular atrial fibrillation (without severe mitral stenosis or mechanical valves)
CHA2DS2-VA score of 2 or greater
Meets guidelines for proper use of Left Atrial Appendage Closure system with increased bleeding risk
Underwent successful Left Atrial Appendage Closure (no significant residual leak or major morbidity)
Suitable for both Non-Antithrombotic Therapy and Single Antiplatelet Therapy
Left Atrial Appendage anatomy compatible with Boston Scientific WATCHMAN FLX Pro device
Willing to return for all required post-procedure visits
Provided written informed consent after understanding the study purpose
You will not qualify if you...
Currently enrolled in other clinical trials except mandatory governmental or purely observational registries
Require long-term anticoagulation for reasons other than atrial fibrillation stroke risk reduction
Require oral antiplatelet therapy for reasons other than Left Atrial Appendage Closure
Contraindicated or allergic to DOAC, VKA, or aspirin
Undergoing or scheduled for cardiac or noncardiac surgery or intervention within 45 days before or 60 days after LAAC
Stroke or transient ischemic attack within 30 days before enrollment
Active bleeding at enrollment
Absence of Left Atrial Appendage or surgical ligation of it
Myocardial infarction within 30 days before enrollment
Previous atrial septal repair or device for atrial septal defect/patent foramen ovale
Presence of mechanical valve prostheses
Contraindications to transesophageal echocardiography
Active infection
NYHA class IV congestive heart failure
Pregnant, breastfeeding, or planning pregnancy
Expected life expectancy less than 2 years
Require emergency surgery
Medical, social, or psychological conditions preventing consent or follow-up
Investigator judgment deeming participation inappropriate for other reasons
AI-Screening
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Your Study Journey
Screening
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
1 visit (in-person)
Treatment
Duration - 45 days
Participants receive either single antiplatelet therapy or no antithrombotic therapy following left atrial appendage closure.
1 visit between 46 and 60 days after randomization
Long-term Monitoring
Duration - Up to 4 years with a minimum of 2 years
Participants are monitored for clinical outcomes including mortality, stroke, bleeding events, and device-related thrombus detection.
Visits at 1 year and 2 years after randomization
Trial Site Locations
Total: 21 locations
1
Nagoya Heart Center
Nagoya, Aichi-ken, Japan, 461-0045
Actively Recruiting
2
Toyohashi Heart Center
Toyohashi, Aichi-ken, Japan, 441-8530
Actively Recruiting
3
New Tokyo Hospital
Matsudo, Chiba, Japan, 270-2232
Actively Recruiting
4
Kokura Kinen Hospital
Kitakyushu, Fukuoka, Japan, 802-8555
Actively Recruiting
5
Gifu Heart Center
Gifu, Gifu, Japan, 500-8384
Actively Recruiting
6
Medical Corporation Sapporo Heart Center Sapporo Cardio Vascular Clinic
No antithrombotic therapy versus single antiplatelet therapy after percutaneous left atrial appendage closure in non-valvular atrial fibrillation: rationale and design of the multicentre, randomised, non-inferiority NAPT-LAAC trial.