Research on Post-Stroke Anticoagulation Strategies for Atrial Fibrillation Based on Left Atrial Appendage Flow Velocity Measured by Intracardiac Echocardiography (ICE)

1. Study Purpose The primary aim of this research was to systematically describe and characterize a novel, thrombus-mimicking artifact observed during Intracardiac Echocardiography (ICE), termed the "Floating Lotus" sign. The study sought to define its imaging features, determine its prevalence, and identify the clinical factors that predict its occurrence. This was driven by the clinical need to prevent the misdiagnosis of this pseudo-thrombus as a true Left Atrial Appendage (LAA) thrombus, which could lead to unnecessary procedure cancellations or anticoagulation changes. 2. Study Population The study population consisted of 172 consecutive patients with non-valvular atrial fibrillation (AF) who underwent ICE-guided catheter ablation and/or left atrial appendage occlusion (LAAO) between January and December 2024 across three tertiary medical centers. Patients with confirmed intracardiac thrombus, significant valvular heart disease, or prior cardiac surgery were excluded. 3. Key Research Focus The key research focus was a multi-faceted investigation of the "Floating Lotus" sign: Incidence and Imaging Characterization: To quantify how common this sign is (found in 27.9% of patients) and meticulously describe its dynamic sonographic appearance-a mobile, echogenic mass within an anechoic space (pericardial effusion) that merges with the LAA wall upon catheter rotation. Identification of Clinical Predictors: To analyze which patient factors are associated with the sign. The study identified heart failure (LVEF \<55%) as the sole independent predictor through multivariable analysis. Clinical Correlation and Differentiation: To examine the sign's association with other clinical parameters (e.g., recent stroke, larger left atrial diameter) and emphasize the critical imaging maneuver (catheter rotation) that differentiates it from a true LAA thrombus, thereby highlighting its direct implications for procedural safety and decision-making.