Clinical implications of left atrial appendage function: its influence on thrombus formation

Area of Science:

• Cardiology
• Echocardiography
• Vascular Ultrasound

Background:

• The left atrial appendage (LAA) is a common site for thrombus formation, particularly in patients with atrial fibrillation.
• Understanding factors influencing LAA blood flow and clot risk is crucial for patient management.

Purpose of the Study:

• To investigate the relationship between left atrial appendage (LAA) function and the occurrence of LAA spontaneous echo contrast (SEC) or thrombus.
• To assess how different LAA blood flow patterns correlate with LAA SEC and thrombus.

Main Methods:

• Transesophageal echocardiography (TEE) was used to evaluate LAA function in 75 patients, measuring LAA area, ejection fraction, and peak emptying velocity.
• Patients were categorized into three groups based on LAA blood flow patterns: biphasic, multiphasic, and very low flow.
• Correlation analysis was performed to determine the association between LAA function parameters and the presence of LAA SEC or thrombus.

Main Results:

• Patients with very low LAA blood flow (Group 3) exhibited the lowest LAA ejection fraction and peak emptying velocity.
• LAA SEC was significantly more prevalent in patients with multiphasic (Group 2) and very low LAA flow (Group 3) compared to those with biphasic flow (Group 1).
• LAA thrombus formation was also significantly higher in patients with poorer LAA function (Groups 2 and 3) compared to Group 1.

Conclusions:

• Impaired LAA function, characterized by reduced ejection fraction and emptying velocity, is associated with a higher incidence of LAA spontaneous echo contrast and thrombus.
• These findings underscore the clinical significance of assessing LAA function to predict thrombotic risk in patients undergoing TEE.