Transesophageal Echocardiography to Identify pAtients With Low Risk of Stroke in Atrial Fibrillation - TIARA Pilot Study

Study Overview
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Brief Summary
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In this multi centre pilot study we will perform TEE in patients with AF who are eligible for VKA treatment. TTE will be used as pre-screening: if TTE shows left atrial abnormalities or aortic plaque, patients will be excluded from randomisation. TEE will be performed in all other patients to detect or exclude complex aorta plaques or signs of left atrial stasis. Three hundred patients who do not have these features on TTE will be randomly assigned to treatment with aspirin or VKA. Follow-up will be 1 year.

Detailed Description
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BACKGROUND Atrial fibrillation (AF) is an independent risk factor for stroke. Therapy with vitamin K antagonists (VKA) and aspirin reduces the risk of thromboembolism (TE) dramatically. Risk stratification is nowadays based on clinical characteristics. However, many high risk AF patients may actually be at low risk, identified by trans-oesophageal echocardiography (TEE). HYPOTHESIS A comprehensive strategy of TEE based aspirin treatment in AF patients eligible for VKA therapy is safe and feasible. OBJECTIVES To show that TEE based aspirin treatment is safe when compared with VKA therapy. To test the feasibility of TEE as a tool to detect all four echocardiographic features of high stroke risk. METHODS In this multi centre pilot study we will perform TEE in patients with AF who are eligible for VKA treatment. TTE will be used as pre-screening: if TTE shows left atrial abnormalities or aortic plaque, patients will be excluded from randomisation. TEE will be performed in all other patients to detect or exclude complex aorta plaques or signs of left atrial stasis. Three hundred patients who do not have these features on TTE will be randomly assigned to treatment with aspirin or VKA. Follow-up will be 1 year. EXPECTED RESULTS Application of a new echo-guided antithrombotic strategy as proposed herein is feasible and may help to reduce bleeding whilst stroke prevention is maintained. If the lower limit of the 95% confidence interval of the yearly incidence of the primary endpoint on aspirin remains below 4.4% then a large multi centre randomised controlled trial will be performed.

Official Title
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Transesophageal Echocardiography to Identify pAtients With Low Risk of Stroke in Atrial Fibrillation

Conditions
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Atrial Fibrillation, Stroke

Intervention / Treatment
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* Procedure: Transoesophageal echocardiography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Documented atrial fibrillation or atrial flutter, paroxysmal or permanent Conventional indication for VKA treatment Signed informed consent Exclusion Criteria: Planned electro cardioversion Very high risk of TE (previous ischemic stroke or systemic TE, symptoms of heart failure or left ventricular dysfunction, mitral valve stenosis, hypertrophic cardiomyopathy) Indication for VKA treatment other than atrial fibrillation (e.g. mechanic valve prosthesis) Atrial fibrillation secondary to reversible diseases (e.g. thyrotoxicosis) Contraindication for treatment with VKA, aspirin, or clopidogrel

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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Aspirin<br>Ascal 100mg once daily | Procedure: Transoesophageal echocardiography<br>* TEE<br>* Other names: No other names;|
| Active Comparator: Coumarin derivates<br>Acenocoumarol or fenprocoumon | Procedure: Transoesophageal echocardiography<br>* TEE<br>* Other names: No other names;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| A composite of the following endpoints: ischemic stroke, systemic embolism, major bleeding, acute coronary syndrome, death. |  | at least 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Completion of a technical adequate TTE/TEE on the four echocardiographic features of high stroke risk. |  | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Echocardiography