D-Dimer-based Indication for Transesophageal Echocardiography to Exclude Left Atrial Thrombus Before Cardioversion of Non-anticoagulated Atrial Fibrillation: A Multicenter Belgian Study

Study Overview
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Brief Summary
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This trial aims at evaluating the number of thromboembolic events post cardioversion in patients receiving a direct current cardioversion with either prior transesophageal echocardiography or D-Dimer (DD) analysis. Patients in need of a direct current cardioversion (DCCV), meeting the criteria for DCCV with prior transesophageal echocardiography (TEE), will be asked to participate in the CARDDI-BEL study. Patients will be randomized on a 1:1 ratio to the TEE-group or DD-group. Patients in the TEE-group will receive TEE prior to cardioversion to exclude left atrial thrombus according to current guidelines [1]. In patients randomized to the DD-group, D-Dimer will be analyzed (cut-off defined by DDage). If the DDage > 10x patient's age, the analysis is suggestive for the presence of left atrial thrombus and the cardioversion will be performed with prior TEE. In case of negative DDage, no TEE will be used in the DD-group.

Official Title
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D-Dimer-based Indication for Transesophageal Echocardiography to Exclude Left Atrial Thrombus Before Cardioversion of Non-anticoagulated Atrial Fibrillation: A Multicenter Belgian Study

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Diagnostic Test: Transesophageal echocardiography
* Diagnostic Test: D-Dimer analysis


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients older than 18 years Patients with non-valvular atrial fibrillation scheduled for direct current cardioversion with prior TEE according to current guidelines Patients willing to sign informed consent Exclusion Criteria: Cardiac surgery within the previous 90 days. Coronary percutaneous transluminal coronary angioplasty/stenting within the previous 90 days or myocardial infarction within the previous 60 days. Significant congenital anomaly or other medical problem that in the opinion of the investigator would preclude enrollment History of blood clotting disease or bleeding abnormalities. Patients with valve implants Women who are pregnant Aortic aneurysm or dissection Documented history of deep vein thrombosis within the last 6 months Documented history of pulmonary embolism within the last 6 months Unwilling or unable to provide informed consent. Recent transient ischemic attack or stroke (90 days) Instable angina

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: TEE-group<br> | Diagnostic Test: Transesophageal echocardiography<br>* Patients randomized to the TEE group will be scheduled for cardioversion with prior TEE<br>|
| Active Comparator: DD-group<br> | Diagnostic Test: D-Dimer analysis<br>* Patients randomized to the DD-group will be scheduled for cardioversion with prior D-Dimer analysis. In case of positive D-Dimer results, TEE will be performed prior to cardioversion<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence in thromboembolic events between both groups after 4 weeks follow-up | The number of thromboembolic events (stroke, transient ischemic attack, ...) in the TEE and DD-group will be compared | up to 4 weeks after cardioversion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between D-Dimer-value (ng/L) and number of thrombi visible on TEE |  | Procedure (At time of cardioversion) | 
| Correlation of DD-value (ng/L) with flow velocity (m/s) in case of spontaneous contrast or suspicion of thrombus in left atrial appendage |  | Procedure (At time of cardioversion) |