Efficacy of Different Anti-Thrombotic Strategies on Device-Related Thrombosis Prevention After Percutaneous Left Atrial Appendage Occlusion

Study Overview
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Brief Summary
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Comparison among three different antithrombotic strategies after percutaneous LAA occlusion with a Watchman FLX LAAC device.

Detailed Description
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Data on the optimal antithrombotic therapy (AT) after percutaneous left atrial appendage (LAA) occlusion are still scarce. The classical AT strategy after LAA occlusion includes 6-weeks of warfarin + aspirin followed by dual anti platelet therapy with clopidogrel (75 mg) and aspirin (81-325 mg) until 6 months of follow-up, then aspirin alone is continued indefinitely. Nonetheless, a significant number of patients continues to suffer from device-related thrombosis which carries a high risk of thromboembolic events. Other AT strategies have been tested in order to reduce the risk of thrombus-formation on device. Among them, replacement of clopidogrel with half-dose oral anticoagulation (OAC) in patients with genetic resistance to this drug has been recently reported to reduce the incidence of DRT. Additionally, reduced dose of novel OAC was demonstrated to lead to lower thrombin generation compared to DAPT.

Official Title
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Efficacy of Different Anti-Thrombotic Strategies on Device-Related Thrombosis Prevention After Percutaneous Left Atrial Appendage Occlusion

Conditions
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Device-Related Thrombosis, Atrial Fibrillation, Left Atrial Appendage Occlusion

Intervention / Treatment
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* Drug: ASA plus Clopidogrel
* Drug: Genetic-Tailored AntiThrombotic Strategy
* Drug: Half-Dose of novel OAC


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men and women ≥18 years of age Successful LAAC procedure (device implanted without procedural or bleeding complication). Patients contraindicated or unsuitable for long-term OAC. History of AF (permanent or persistent or paroxysmal). Written informed consent by the patient or designee if the patient is unable to consent Exclusion Criteria: Life expectancy < 2 years. Pregnant, breastfeeding, or unwilling to practice birth control during participation in the study. Presence of a condition or abnormality that in the opinion of the Investigator would compromise the safety of the patient or the quality of the data

Ages Eligible for Study
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Minimum Age: 18 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Standard Antithrombotic Therapy<br>OAC for 6 weeks followed by DAPT until 6 month-follow-up, then aspirin alone | Drug: ASA plus Clopidogrel<br>* OAC (6 weeks) + DAPT (until 6 months) + ASA<br>|
| Active Comparator: Genetic-Tailored AntiThrombotic Strategy<br>OAC for 6 weeks followed by DAPT (clopidogrel responders) or aspirin plus half-dose OAC (clopidogrel non-responders) until 6 month-follow-up, then aspirin alone | Drug: Genetic-Tailored AntiThrombotic Strategy<br>* Half-Dose OAC or Clopidogrel in combination with ASA on the basis of CYP2C19 Genotype<br>|
| Active Comparator: Half-Dose NOAC<br>Half Dose of Novel OAC | Drug: Half-Dose of novel OAC<br>* Half Dose of novel OAC post-device Implantation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Composite of Stroke, Systemic Embolism, and Device-related Thrombosis |  | 1 year | 
| Incidence of Major Bleeding Events |  | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of Minor Bleeding Events |  | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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left atrial appendage, Watchman, antithrombotic therapy, device-related thrombosis