Left atrial appendage morphology is closely associated with specific echocardiographic flow pattern in patients with atrial fibrillation

AIMS: To assess the relation between left atrial appendage (LAA) morphology and echocardiographic flow pattern of the LAA by means of two- and three-dimensional transoesophageal echocardiography (3D-TEE).

METHODS AND RESULTS: In a total of 131 patients with atrial fibrillation, LAA morphology was analyzed by 3D-TEE and classified into four types (Chicken Wing, Windsock, Cactus, Cauliflower). Left atrial appendage flow pattern as maximal LAA emptying flow velocity and spontaneous echo contrast (SEC) were retrieved from 2D-TEE imaging in all patients. In patients with atrial fibrillation (AF), Chicken Wing morphology was associated with a higher LAA emptying flow velocity (difference of means = -11.7, 95% CI 4.6-19.3, P = 0.003) and a reduced prevalence of SEC (OR 3.2, 95% CI 1.1-9.3, P = 0.025) compared with all other LAA types (so-called 'Non-Chicken Wing' LAA). These alterations were irrespective of the underlying type of AF.

CONCLUSION: Non-Chicken Wing LAA morphologies are associated with a specific echocardiographic flow pattern in patients with AF. Since evidence exists that LAA flow pattern are indicative of an enhanced risk of thrombus formation, 3D-TEE might be a valuable tool warranting future studies to test whether these morphological and functional characteristics permit risk stratification in AF.