Detection and prevalence of intra-cardiac thrombus in patients with embolic stroke of undetermined source

Background: Embolic Stroke of Undetermined Source (ESUS) is defined as non-lacunar brain infarct without proximal arterial stenosis or known cardioembolic source (including atrial arrythmias). Little is known about the prevalence of intra-cardiac thrombus as a potential source of embolism in patients presenting with ESUS.

Objectives: To examine the use of contrast-enhanced electrocardiogram-gated computed tomography (CT) to elucidate the prevalence of intra-cardiac thrombus in patients suspected of ESUS.

Methods: We retrospectively investigated 101 consecutive patients who presented to our hospital with ESUS between January 2019 and March 2021 and underwent 2D echocardiography and CT as part of stroke etiology evaluation.

Results: In our study population (73.2 ± 9.98 years, 41% female), CT detected intra-cardiac thrombus in 19 (18.8%) patients. Left ventricular thrombus (LVT) was found in 10 (9.9%) patients and left atrial/left atrial appendage in 8 (7.9%) patients. All of cases of LVT were detected by using cardiac CT, while 2D echocardiography was able to detect only four of these cases. All cases of LVT were associated with significant coronary obstructive disease, while in 2 out of 10 patients, a previous history of ischemic heart disease was unknown. Using CT, 2 patients after transcatheter aortic valve implantation were diagnosed with hypoattenuated leaflet thickening ,and 3 patients with pulmonary embolism. In total, the finding of CT resulted in change of management, i.e. indication for anticoagulation instead of antiplatelets drugs, in 23 (22.7%) patients.

Conclusion: CT is useful to enhance the detection of intra-cardiac thrombus among patients presenting with ESUS. The imaging provides relevant information for anticoagulation treatment and need of further coronary evaluation and intervention.