Comparison of cardiac computed tomography and transesophageal echocardiography for left atrial appendage thrombus detection

BACKGROUND AND OBJECTIVE: Pulmonary vein isolation (PVI) is a common intervention for symptomatic atrial fibrillation (AF). Transesophageal echocardiography (TEE) and cardiac computed tomography (CCT) are commonly used pre-PVI to assess left atrial (LA) and left atrial appendage (LAA) thrombus and visualize LA and pulmonary vein anatomy. This retrospective study aims to compare CCT and TEE in detecting LAA thrombus in patients with symptomatic paroxysmal or persistent AF scheduled for PVI. METHODS: Seven hundred five patients underwent routine TEE and CCT within 24 h. Patients with prior LAA thrombus, cardioembolic stroke, or contraindications to TEE were excluded. The presence or absence of LAA thrombus and other potential thrombus-inducing factors were evaluated using TEE and CCT, and the diagnostic performance of the two imaging modalities was compared. RESULTS: Most patients had paroxysmal AF (54.2%) and a high CHA₂DS₂-VASc score (47.6%). TEE detected LAA thrombus in 1.8%, while 7% had SEC without thrombus. Cardiac CT scans showed LAA filling defects in 17.2%. Using TEE as the reference, CCT demonstrated high sensitivity (92.3%) and negative predictive value (99.8%), but low specificity (84.2%) and positive predictive value (9.9%) for LAA thrombus detection. CONCLUSION: The study supports CCT as a reliable imaging method for excluding LAA thrombus in AF patients scheduled for PVI. In cases where CCT shows no thrombus and adequate anticoagulation is ensured, catheter ablation and DCCV procedures can be safely considered.