Platelet-activation and Optimal Inhibition in Patients With Atrial Fibrillation Undergoing Left Atrial Appendage Occlusion

Study Overview
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Brief Summary
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The POPULAR-LAAO registry is an open-label observational prospective registry to investigate hemostatic processes following left atrial appendage occlusion.

Detailed Description
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This is an open-label observational prospective registry. The aim is to develop a better understanding of coagulation, platelet reactivity and prothrombotic factors in the first months after left atrial appendage occlusion, as occurrence of device-related thrombus and optimal postprocedural management remain a challenge after LAAO. The study population will consist of patients with non-valvular atrial fibrillation (AF) at risk for cardio-embolic stroke scheduled for left atrial appendage occlusion. In these patients, blood samples for coagulation and platelet reactivity testing will be taken, which will be gathered prior to the procedure and 1 day, 14 days, 3 months and 6 months after the procedure. Data will be analyzed longitudinally and between groups based on patient characteristics.

Official Title
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Platelet-activation and Optimal Inhibition in Patients With Atrial Fibrillation Undergoing Left Atrial Appendage Occlusion; The POPULAR-LAAO Trial

Conditions
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Atrial Fibrillation

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The subject is aged 18 years or older The subject is accepted/scheduled for left atrial appendage occlusion The subject has a CHA₂DS₂-VASc Score ≥2 (male) or ≥3 (female) The subject or legal representative is able to understand and is willing to provide written informed consent to participate in the trial. Exclusion Criteria: Unable or unwilling to return for required follow-up visits and examinations Mechanical heart valves or valvular disease requiring surgery or interventional procedure Ongoing major bleeding or complicated or recent (<72hours) major surgery Known large oesophageal varices or decompensated liver disease (unless a documented positive opinion of a gastro-enterologist) Severe thrombocytopenia (<50,000/ml) High likelihood of being unavailable for follow-up or psycho-social condition making study participation impractical. Woman with child bearing potential who do not use an efficient method of contraception. Positive serum or urine pregnancy test for woman with child bearing potential Pregnancy or within 48 hours post-partum unsuitable LAA anatomy for occlusion or thrombus in the LAA at the time of procedure contraindications or unfavourable conditions to perform cardiac catheterization or transesophageal echocardiography (TEE) atrial septal malformations, atrial septal defect or a high-risk patent foramen ovale that may cause thrombo-embolic events atrial septal defect repair or closure device or a patent foramen ovale repair or any other anatomical condition as this may preclude an LAAO procedure Mitral valve regurgitation grade 3 or more Aortic valve stenosis (AVA<1.0 cm2 or Pmax>50 mmHg) or regurgitation grade 3 or more Planned carotid endarterectomy (CEA) for significant carotid artery disease Life expectancy of less than 1 year

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Left Atrial Appendage Occlusion<br>Patients undergoing left atrial appendage occlusion. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in coagulation activation | Influence of LAAO on coagulation activation over time | Pre-LAAO and post-LAAO (1 day, 2 weeks, 3 months, 6 months) | 
| Change in platelet reactivity | Influence of LAAO on platelet reactivity over time | Pre-LAAO and post-LAAO (1 day, 2 weeks, 3 months, 6 months) | 
| CYP2C19 genotype | Rate of clopidogrel non-responders among LAAO patients will be assessed by determining CYP2C19 genotype | Pre-LAAO | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Separate and composite event rates of stroke (ischemic or hemorrhagic), transient ischemic attack (TIA), systemic embolism and cardiovascular death. |  | Post-LAAO (3 months, 6 months, 12 months) | 
| Major and minor bleeding event rate (according to Bleeding Academic Research Consortium criteria) |  | Post-LAAO (3 months, 6 months, 12 months) | 
| Device related thrombus event rate |  | Post-LAAO (3 months, 12 months) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Left atrial appendage occlusion, Device-related thrombus, Platelet reactivity, Coagulation activation