Left atrial appendage geometry and function using transesophageal three-dimensional echocardiography in atrial fibrillation: a new approach to characterize left atrial thrombogenic milieu

Abstract

Abstract Background Little data is available on the evaluation of left atrial appendage (LAA) geometry and function using three-Dimensional (3D) transoesophageal echocardiography (TEE). Purpose We hypothesized that 3D LAA geometry evaluated using dedicated TEE software could be integrated in the evaluation of the thromboembolic milieu in patients hospitalized for atrial fibrillation (AF). Methods We prospectively studied 206 hospitalized patients with AF with two-dimensional transthoracic echocardiography (TTE) and 3D TEE of the LAA within 24 hours of admission. 3D parameters were analysed off-line using Tomtec software (4D Cardio-View, Generic Volume, Philips) (Figure 1). Patients were divided into two groups according to the presence (n = 35) or absence (n = 171) of LAA sludge/thrombus on admission. Results Patients with LAA sludge/thrombus had more frequently a history of heart failure together with higher values of BNP, CRP and hemoglobin. These patients received less frequently angiotensin II receptor antagonist treatment on admission. Concerning the echocardiographic characteristics, patients with LAA sludge/thrombus exhibited higher left atrial (LA) volume, lower left ventricular ejection fraction (LVEF) and cardiac output. In the 2D TEE study they had lower LAA emptying and filling flow velocities compared to those without sludge/thrombus. 3D TEE showed overall higher 3D end-systolic (ES) and end-diastolic (ED) LAA measurements (ostium area, length, volume), and more frequently the absence of a chicken wing morphology. There were no intergroup differences regarding the number of LAA lobes (Table 1). Conclusion 3D characterization of LAA geometry and function depicts a degree of appendage remodeling in AF that appears to be associated with the degree of thrombogenicity. Further investigation is needed to determine the impact of this remodeling on outcomes in these patients.