Carotid Free-Floating Thrombus in the Setting of Bilateral Embolic Strokes: A Case Report

Carotid free-floating thrombus (CFFT) is a rare entity that can lead to life-threatening embolic events. An 80-year-old man presented with left-sided weakness. Computed tomography angiography (CTA) demonstrated bilateral carotid plaques with pedunculated mural thrombi and no hemodynamically significant stenosis. After intracranial hemorrhage was excluded, intravenous tissue plasminogen activator was administered. Within 12 hours, he developed a contralateral ischemic stroke; repeat CTA showed disappearance of the left internal carotid artery (ICA) thrombus, while magnetic resonance imaging demonstrated a new left hemispheric infarction. Carotid duplex ultrasound revealed a mobile right ICA thrombus consistent with CFFT. Urgent carotid endarterectomy (CEA) was performed without complications, and no further neurological events or hemorrhagic transformation occurred. This case suggests that urgent CEA may help prevent further embolic events in selected patients with CFFT.