Complex Left Atrial Appendage Morphology and Left Atrial Appendage Thrombus Formation in Patients With Atrial Fibrillation

Abstract

Background-In patients with atrial fibrillation (AF), most thrombus forms in the left atrial appendage (LAA). However, the relation of LAA morphology with LAA thrombus is unknown. Methods and Results-We prospectively enrolled 633 consecutive patients who were candidates for catheter ablation for symptomatic drug-resistant AF. Transesophageal echocardiography (TEE) was performed to assess LAA thrombus. LAA structure was assessed by 3-dimensional TEE. LAA orifice area, depth, volume, and number of lobes were measured on reconstructed 3-dimensional images. Clinical characteristics and echocardiographic measures were compared to determine variables predicting LAA thrombus.

Percutaneous left atrial appendage occlusion: New perspectives for the method

“…An increased number of lobes was associated with the presence of a thrombus independent of the clinical risk [18]. The "cauliflower" morphology is most often associated with embolic events.…”

Left Atrial Appendage Exclusion for Atrial Fibrillation

“…In a Japanese study of 564 patients with 3D-TEE, left atrial volume and number of LAA lobes were independently associated with LAA thrombus, with 94% (32/34) of those with thrombus having 3 or more lobes. 98 In contrast, LAA ostial size has been associated with both an increased 32 and decreased 97 …”

Association of Thromboembolic Risk Score with Left Atrial Thrombus and Spontaneous Echocardiographic Contrast in Non-Anticoagulated Nonvalvular Atrial Fibrillation Patients

“…Previous studies have shown that non-paroxysmal AF [35], LAE [5,18,21,[36][37][38][39][40], and impaired LVEF [35][36][37][38][39] were independent risk factors for LAT/SEC. Consistent with these observations, clinical studies or meta-analysis using thromboembolic events as the end point also showed that non-paroxysmal AF increased risk for AFrelated thromboembolism [41], and that LAE [42,43] and impaired LVEF [42,44] were the independent predictors of thromboembolic events.…”