Prevalence and predictors of left atrial thrombosis in atrial fibrillation patients treated with non-vitamin K antagonist oral anticoagulants

Background: Few data are available regarding the prevalence of left atrium (LA) thrombi in atrial fibrillation (AF) patients treated with non-vitamin K antagonist oral anticoagulants (NOACs). Methods: We evaluated the prevalence and predictors of LA/LA appendage (LAA) thrombi in non-valvular AF patients treated with NOACs referring to a single centre for a scheduled electrical cardioversion (ECV) or catheter ablation (CA). Transesophageal echocardiography (TEE) was performed within 12 h prior to the index procedure. Results: A total of 352 consecutive patients with non-valvular AF treated with NOACs were included in this analysis (ECV group n = 176 and CA group n = 176) between 2013 and 2018. 85 patients (24.2%) were on dabigatran, 150 (42.7%) on rivaroxaban, 104 (29.6%) on apixaban and 13 (3.7%) on edoxaban. A LA/LAA thrombus was detected by TEE in 27 (7.7%) patients, 18 in the ECV group and nine in the ablation group; 18 (5.1%) patients presented dense LA/LAA spontaneous echo contrast (SEC). Predictors of LA/LAA thrombi were a CHA2DS2-VASc score > 3 (OR 4.54, 95% CI 1.50 − 13.70, p value =.007) and obesity (OR 6.01, 95% CI 1.95 − 18.50, p value =.001). Conclusions: Among real-world patients with non-valvular AF treated with NOACs, we found a high incidence of LA/LAA thrombi compared to previous reports. The main predictors of LA/LAA thrombosis were a CHA2DS2-VASc score > 3 and obesity.