Real-world incidence and predictors of left atrial thrombus detected on transesophageal echocardiography before atrial fibrillation ablation procedures

BACKGROUND: Transesophageal echocardiography (TEE) is routinely performed before atrial fibrillation (AF) electrotherapy to exclude left atrial thrombus. AIMS: The aim of this study is to assess the real-world prevalence of left atrial appendage thrombus (LAAT) and improve risk stratification to limit the number of unnecessary TEE examination. METHODS: We retrospectively analyzed 7357 TEE exams at a high-volume hospital to assess LAAT prevalence. Subsequently, we prospectively studied 517 consecutive patients in whom TEE was routinely performed prior to elective AF ablation, to assess LAAT and spontaneous echocardiographic contrast (SEC) prevalence. RESULTS: LAAT was detected in only 1.5% (108/7357) of all TEE studies performed for various indications. In elective AF ablation patients, LAAT or dense SEC was found in only 1.6% of cases (8/511).Predictors of LAAT/SEC were as follows: persistent AF over one year (odds ratio [OR], 0.20; 95%confidence interval [CI], 0.05-0.7; P = 0.012), and at least moderate valvular heart disease or postvalve repair/replacement status (OR, 0.46; 95% CI, 0.22-0.98; P = 0.044). Conversely, the identified protective factors included the following: CHA₂DS₂-VA score