Hur J, Kim YJ, Lee HJ et al. Stroke 2011;42:2471–7.
In the present study, the authors assessed the diagnostic performance of a cardiac computed tomography (CT) protocol for detection of left atrial appendage thrombi and for differentiation between thrombus and circulatory stasis in patients with stroke, using transesophageal echocardiography as the reference standard. The overall sensitivity and specificity of CT for the detection of thrombi and circulatory stasis in the left atrial appendage were 96% and 100%, respectively. This newly proposed cardiac CT protocol is a non-invasive, sensitive modality for detecting left atrial appendage thrombi, albeit at the expense of an additional radiation exposure and a risk of contrast-induced nephropathy.
Cardiogenic emboli have been estimated to be the causative factor in 20–40% of all stroke cases. Currently, transesophageal echocardiography (TEE) has emerged as the most sensitive technique for the detection of intracardiac thrombi. However, TEE is a semi-invasive method that in some cases is performed under sedation. Computed tomography (CT) is a sensitive alternative modality for the detection of intracardiac thrombus, which is seen as a filling defect on a CT scan. However, using an early-enhanced CT scan, it is not possible to differentiate between a filling defect caused by a thrombus versus that caused by a circulatory stasis (spontaneous echo contrast [SEC]) in the left atrial appendage (LAA).