Carotid Artery Free-Floating Thrombus Caused by Paradoxical Embolization From Greater Saphenous Vein Ascending Thrombophlebitis Luigi Irace, 1 Roberto Gabrielli, 1 Maria Sofia Rosati, 1 Maria Fabrizia Giannoni, 2 Anna Castiglione, 2 Antonella Laurito, 2 and Bruno Gossetti, 2 Rome, Italy Stroke of unknown origin in young patients is seen to be closely correlated with patent foramen ovale (PFO) than stroke in patients with established stroke mechanisms. We report a case of a young woman without cardiovascular risk factors who was admitted to our emer- gency department with listlessness and altered mental status. The clinical examination revealed right lower limb swelling. Magnetic resonance imaging and contrast-enhanced computed tomographic scans revealed a free floating thrombus of the left internal carotid artery (ICA) with a large bilateral frontal ischemic lesion. The diagnosis of a medium-sized PFO with moderate right-to-left contrast shunting was made after transesophageal echocardi- ography. No other cardiac sources for embolization were detected, while an ascending throm- bophlebitis of the right greater saphenous vein was detected by venous Doppler ultrasonography. These findings support the diagnosis of ICA free-floating thrombus caused by paradoxical embolization (via the PFO) of clot from the greater saphenous vein. The patient underwent emergency saphenofemoral disconnection with femoral vein thrombectomy and subsequently carotid artery thrombectomy under general anesthesia. No carotid athero- matous wall lesions were detected at surgical exploration; no immunologic pathology, hyper- coagulable status, or malignancy were recorded. No hemorrhagic cerebral complications were observed in the postoperative period, and the patient had an improvement of her neurologic status (a reduction of the National Institutes of Health Stroke Scale score from 7 to 3). Her recovery was uneventful. The patient was transferred for rehabilitation on postoperative day 5 with oral anticoagulation. Six-month ultrasound follow-up revealed deep and superficial venous system and carotid artery patency. The patient was asymptomatic and anticoagulation was discontinued. Paradoxical cerebral embolization through a PFO is a rare phenomenon that, in our patient, appeared to have resulted in stroke caused by a free-floating thrombus in the ICA. Accurate evaluation of carotid and lower limb veins by duplex scan is mandatory in cases of stroke of unknown origin, and urgent surgical repair can be useful in order to improve the clinical outcome. INTRODUCTION Free-floating thrombus (FFT) in the internal carotid artery (ICA) and paradoxical embolization through a patent foramen ovale (PFO) are rare conditions, and their true incidence is unknown. The clinical presentation may range from completely asymp- tomatic to a devastating stroke, 1,2 and it can be diag- nosed by indirect evidence and could be cause a cerebral vascular event. 1 1 Department of Emergency ‘‘Policlinico Umberto I,’’ ‘‘Sapienza’’ University of Rome, Rome Italy. 2 Department of Vascular Surgery A, ‘‘Policlinico Umberto I,’’ ‘‘Sapienza’’ University of Rome, Rome Italy. Correspondence to: Roberto Gabrielli, MD, PhD, Via Don Luigi Sturzo 9 Anguillara Sabazia, Rome 00061, Italy; E-mail: rogadoc@ libero.it Ann Vasc Surg 2013; 27: 499.e13e499.e17 http://dx.doi.org/10.1016/j.avsg.2012.06.020 Ó 2013 Elsevier Inc. All rights reserved. Manuscript received: February 13, 2012; manuscript accepted: June 11, 2012. 499.e13