Left atrial appendage thrombus in acute stroke: diagnostic accuracy of CT angiography compared to transesophageal echocardiography

Abstract

ObjectivesTo evaluate the value of an extended emergency computed tomography angiography (CTA) including cardiac imaging in patients with acute ischemic stroke for the detection of left atrial appendage (LAA) thrombus compared to transesophageal echocardiography (TEE) as a reference standard. Materials and MethodsWe conducted a retrospective case-control study of patients with presumed acute ischemic stroke who had undergone non-ECG-gated CTA for the craniocervical vessels with an extended coverage including the heart in the context of emergency stroke evaluation and for whom TEE was available as part of the routine stroke diagnostic. We selected cases with evidence of LAA thrombus in TEE and controls without LAA thrombus in TEE in a 1:3 ratio. Two independent observers analyzed CTA images for presence of LAA thrombus and were blinded to the presence of thrombus in TEE. ResultsTwenty-two patients with LAA thrombus in TEE, and 66 patients without LAA thrombus in TEE were included. The detection of LAA thrombus using CTA showed a sensitivity of 63.6%, a specificity of 81.8%, a positive predictive value of 53.9% and a negative predicted value of 87.1%. Interobserver agreement was only moderate (Cohen´s κ = 0.43). ConclusionsAn extended emergency CTA including cardiac imaging can be helpful in early risk stratification in patients with stroke of cardioembolic origin. However, our data show that a standard CTA of craniocervical vessels with extended coverage of the heart is of limited value when compared to TEE, the standard method of detecting LAA thrombi.