Background: Thrombi of the left atrial appendage (LAA) are common source of stroke and its detection may clearly affect patient management. Although, transesophageal echocardiography (TEE) is believed to be the single best modality for patients with suspected intracardiac thrombi, we assessed the diagnostic performance of 64-slice computed tomographic coronary angiography (CTCA) for detection of the LAA thombus in stroke patients. Methods and Materials:Hundred-one patients with a recent episode of stroke suspected for cardioembolic source, who underwent both 64-slice CTCA and TEE, were selected. All examinations were performed within 1 week. The number of thrombus detected upon both CTCA and TEE were recorded, and agreement between detection of thrombus with CT and TEE was assessed with 觀 statistics. Results: In 101 patients, there were total 8 thrombi detected by TEE. The overall sensitivity, specificity, positive predictive value and negative predictive value of 64-slice CTCA for detection thrombus in the LAA were 100%, 96%, 67%, and 100%, respectively. Concordance between detection of thrombus in the LAA with 64-slice CTCA and TEE was high: no thrombus (CT and TEE); 89 patients, thrombus (CT and TEE); 8 patients, and thrombus (CT), no thrombus (TEE); 4 patients (overall 觀=0.876). Conclusions: We found that 64-slice CTCA is a noninvasive and very sensitive modality in detecting thrombus in the LAA in stroke patients. Although, TEE is considered as the gold standard modality for detecting LAA thrombus, 64-slice MDCT has a potential to be become a useful modality for detection of intracardiac thrombus.