Efficacy of Optison Echo Contrast to Detect Thrombus in Left Atrial Appendage

Study Overview
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Brief Summary
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The investigators intend to determine if using Optison echocardiography contrast increases sensitivity and specificity of detecting left atrial appendage thrombus in transesophageal echocardiography studies as opposed to standard 2D and 3D TEE imaging without the use of echo contrast.

Detailed Description
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Accurate determination of the presence or absence of left atrial appendage (LAA) thrombus has a large impact on the clinical course of patients with atrial fibrillation or ischemic stroke and has large financial implications as well. Misdiagnosing the presence of LAA thrombus can lead to unnecessarily cancelled procedures (cardioversion and atrial fibrillation ablation) and potentially hazardous, unnecessary changes in clinical care (such as prolonged Coumadin anticoagulation). Missing LAA thrombus can result in continuation of cardioversion or atrial fibrillation ablation procedures at a time when there is higher risk of subsequent embolic stroke. Several of the patients with atrial fibrillation require transesophageal echocardiography (TEE) performed prior to cardioversion or atrial fibrillation ablation procedures. There is opportunity to enroll most of these patients in our proposed study. There has been essentially no work published about the use of echo contrast materials in TEE (other than agitated saline), particularly the use of Optison. Thus, the investigators will be exploring a new field in echocardiography and echo contrast.

Official Title
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The Use of Optison Echocardiography Contrast in the Detection of Left Atrial Appendage Thrombus With Transesophageal Echocardiography.

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Drug: Optison echocardiography contrast agent


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: > 18 years old Cognitively sound and able to provide informed consent Indicated for TEE as a standard clinical procedure for evaluation of cardiac health status. Exclusion Criteria: Contraindicated for Optison administration Known right-to-left or bi-directional cardiac shunts Hypersensitivity to perflutren, blood, blood products or albumen Women who are pregnant Removal of Left Atrial Appendage Not able to provide informed consent

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 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: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Echo arm<br>Subjects with atrial fibrillation who are undergoing a TEE procedure will be assessed using Optison echocardiography contrast agent | Drug: Optison echocardiography contrast agent<br>* Subjects undergoing transesophageal echocardiography who will receive the Optison contrast agent during the procedure to test if the image quality improves to provide accurate assessment of the presence of left atrial thrombus.<br>* Other names: Perflutren Protein-Type A microspheres;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percent Confidence in Assessment of Left Atrial Appendage Thrombus | Confidence among echo readers to determine presence or absence of left atrial appendage thrombus before and after injection of Optison contrast agent. Percent confidence was calculated from a subjective assessment made by each reader after viewing the echo images. A six-point scale was used by the readers to grade the subjective assessment of their confidence in detecting thrombus; a score of 0 representing 0% (no confidence) up to a score of 5 representing 100% (total confidence) that the interpretation was correct for presence or absence of left atrial appendage thrombus. The reported percent confidence is the average of both echo readers. | One Transesophageal Echocardiography, up to 1 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Concordance Between Echo Readers in Determining Presence or Absence of Thrombus in the Left Atrial Appendage | Percent agreement between echo readers to determine presence or absence of left atrial appendage thrombus before and after injection of Optison contrast agent | One transesophageal echocardiography, up to 1 hour | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Atrial fibrillation, stroke, TEE, Left atrial thrombus