Average e′ velocity on transthoracic echocardiogram is a novel predictor of left atrial appendage sludge or thrombus in patients with atrial fibrillation

Studies have demonstrated the value of transthoracic echocardiogram (TTE) diastolic parameters in predicting left atrial appendage (LAA) thrombus; however, these studies have been small. We aim to clarify the relationship between TTE diastolic parameters, in particular average e', and LAA thrombus or sludge.A case-control review was conducted of subjects with non-valvular atrial fibrillation (n = 2263) who had undergone TEE (transesophageal echocardiogram) and had a TTE within 1 year of TEE. Cases of LAA sludge or thrombus were matched to controls by age, sex, left ventricular ejection fraction (LVEF), and anticoagulation status.Forty-three subjects (mean age 73 ± 12, 65% male, LVEF 47%, 44% on anticoagulation) with LAA sludge or thrombus were identified. Compared to matched controls, average TTE e' (7.3 ± 2.1 cm/s vs 8.7 ± 2.1 cm/s, P < 0.001) and the E:e' ratio (15 ± 7 cm/s vs 12 ± 5 cm/s; P = 0.005) were significant predictors of LAA sludge or thrombus. Average TTE e' value of >11 cm/s had 100% sensitivity for ruling out LAA sludge or thrombus.In individuals with atrial fibrillation, average e' >11 cm/s on TTE is a promising independent predictor of the absence of LAA sludge or thrombus on TEE.