Long-Term Outcomes of LAA Contrast Flow in CT Scans After Endocardial LAA Closure: The CF-CT Registry

Study Overview
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Brief Summary
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This study is intended to assess the incidence and correlation to the development of peri-device leaks (PDLs), device related thrombosis (DRTs) and cerebral vascular accident (CVA)/transient ischemic attacks (TIAs) in association with left atrial appendage contrast flow (LAA-CF). It will be a multi-center, retrospective study. Approximately 100 subject charts will be reviewed.

Detailed Description
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Although the clinical significance of long-term left atrial appendage contrast flow (LAA-CF) in computerized tomography (CT) scan is unknown, study by Lim et al reported that 45 days are not enough for complete left atrial appendage (LAA) seal-off after left atrial appendage occlusion (LAAO) in humans and anatomic closure may not necessarily ensure treatment success. Long-term monitoring is warranted in high-risk patients with LAAO after switching from anticoagulation to antiplatelet therapy. They reported possible explanations for residual LAA-CF after LAAO to be related to peri-device gaps, incomplete endothelialization on the device surface, an off-axis device, fabric leak through the non-endothelialized portion of the device. To this date no studies or registries exist on long term follow up and association of Left Atrial Appendage Contrast Flow (LAA-CF). In this study with two FDA approved devices (Watchman/Watchman FLX and Amplatzer Amulet), it is hypothesized that the LAA contrast-flow (CF) rate is related to lack of endothelization of the implanted devices and potentially associated with peri-device leaks (PDLs), device related thrombosis (DRT).

Official Title
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Long-Term Outcomes of Left Atrial Appendage Contrast Flow in CT Scans After Endocardial LAA Closure: The CF-CT Registry

Conditions
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Atrial Fibrillation, Ischemic Stroke, Acute

Intervention / Treatment
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* Other: Left Atrial Appendage Occlusion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subjects must be at least 18 years of age. Subjects underwent LAA closure with Watchman/Watchman FLX or Amplatzer Amulet at our institution from January 2019 till June 2022 Exclusion Criteria: No definite exclusion criteria are defined for the study as all patients with Watchman-FLX or Amplatzer Amulet will be included in the study.

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 |
| --- | --- |
| Amplatzer Amulet<br>This is the group of subjects who are implanted with Amplatzer Amulet device. | Other: Left Atrial Appendage Occlusion<br>* Acute ischemic stroke is a major cause of morbidity and mortality in non-valvular Atrial Fibrillation (AF). Oral Anticoagulation (OAC) with Warfarin and Direct oral anticoagulants (DOACs) has been the mainstay to prevent systemic thromboembolism (STE) in this patient population. It is estimated that around 50% of patients who have AF with indication for OAC end up being not on OAC due to bleeding complications leaving them at high risk for developing STE. Left atrial appendage occlusion (LAAO) offers an option in such population.<br>|
| Watchman / Watchman FLX<br>This is the group of subjects who are implanted with Watchman / Watchman FLX device. | Other: Left Atrial Appendage Occlusion<br>* Acute ischemic stroke is a major cause of morbidity and mortality in non-valvular Atrial Fibrillation (AF). Oral Anticoagulation (OAC) with Warfarin and Direct oral anticoagulants (DOACs) has been the mainstay to prevent systemic thromboembolism (STE) in this patient population. It is estimated that around 50% of patients who have AF with indication for OAC end up being not on OAC due to bleeding complications leaving them at high risk for developing STE. Left atrial appendage occlusion (LAAO) offers an option in such population.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence and correlation to the development of Peri-Device Leak (PDLs), Device-Related Thrombus (DRT) or cerebral vascular accident (CVA) in association with LAA-CF | Incidence and correlation to the development of PDLs, DRTs or CVA in association with LAA-CF will be assessed. These will be noted as either Yes or No. | 12 Months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total time to complete endothelization or no LAA-CF | Total time to complete endothelization or no LAA-CF will be assessed. | 12 Months | 
| Association of device size with LAA-CF | Association of device size with LAA-CF will be assessed. | 12 Months | 
| Association of landing zone with LAA-CF | Association of landing zone with LAA-CF will be assessed. | 12 Months |