Considerations beyond Stenosis for Carotid Endarterectomy in Treating Free-Floating Thrombus of the Carotid Artery

Background: Free-floating thrombus (FFT) of the carotid artery is an uncommon condition that can present with neurologic symptoms, often in the setting of ischemic stroke. The literature pertaining to the incidence and optimal treatment of this condition is limited. Herein, we report our contemporary experience with FFT across a range of degrees of carotid stenosis. Methods: Medical records and imaging studies from a single academic medical center from January 2016 to July 2018 were retrospectively reviewed. Patient demographics, presentation, treatment, and follow-up were abstracted. Results: Six cases of FFT of the carotid artery with and without hemodynamically significant atherosclerotic disease were identified. All cases presented with ischemic stroke; one case had a hemorrhagic conversion. In each case, the FFT was visualized by at least one imaging modality including computed tomography angiography, magnetic resonance angiography, and duplex ultrasound. Three patients had >50% carotid stenosis and three had <50%. All cases were treated with endarterectomy. Four of the six patients received preoperative anticoagulation. There were no postoperative complications. Median follow-up was 252 days, with one case lost to follow-up. Four of the six patients have been without restenosis, recurrence of the thrombus, nor worsening or recurrent stroke on follow-up. The fifth patient developed restenosis but remained clinically stable. Conclusions: Although current society guidelines do not recommend carotid endarterectomy as first-line treatment for symptomatic patients with <50% stenosis, it may be indicated in the context of FFT.