Refining the Prothrombotic State and Prognosis in Atrial Fibrillation With Left Atrial Appendage 3D Echocardiography

Abstract

BACKGROUND: Left atrial (LA) volume is an echocardiographic marker of remodeling, thromboembolic risk, and prognosis in atrial fibrillation (AF); limited data are available on LA appendage (LAA) characterization beyond morphology. We sought to evaluate LAA characteristics in 2-dimensional (2D) and 3-dimensional (3D) transesophageal echocardiography (TEE) and the correlation with LA/LAA prothrombotic state and prognosis. METHODS: We prospectively studied 206 hospitalized patients with AF using 2D transthoracic echocardiography (TTE) and 2D/3D TEE of the LAA ≤24 hours from admission. Patients were divided according to the presence or absence of LAA sludge and/or thrombus. Data on clinical events were collected for 2 years. RESULTS: Patients with LAA sludge/thrombus (n=35) on admission had higher LA volumes, lower left ventricular ejection fraction, lower LAA emptying and filling flow velocity, larger 2D LAA measurements (2D LAA ostium diameter, 2D LAA area) as well as larger 3D LAA measurements (higher 3D LAA volumes (LAAV), higher 3D end-systolic [ES] LAA ostium area), and more frequently non-chicken wing morphology. On multivariable logistic regression analysis, LAA filling flow velocity and 3D ES LAAV were associated with the presence of LAA sludge/thrombus at admission (P=0.031 and P<0.0001 respectively). Receiver operating characteristic curve analysis revealed the optimal cut-off for 3D ES LAAV to discriminate patients at risk of death within 2 years was 9.3 mL. Kaplan–Meier curves demonstrated a significant difference in survival at 2-year follow-up according to this value: 3 deaths occurred in the group with 3D ES LAAV <9.3mL and 11 in those with volume ≥9.3 mL (P=0.02). CONCLUSIONS: 3D characterization of LAAV depicts a degree of LAA remodeling in AF that appears associated with LA/LAA thrombogenicity and mid-term prognosis.