A Case of Carotid Free-floating Thrombus Longitudinally Extending to the Craniocervical Junction after Intravenous Thrombolytic Therapy for Acute Internal Carotid Artery Occlusion

Carotid free-floating thrombus (CFFT) is rare with less than 150-200 cases reported in the literature. Most previous reports were related to the spontaneous onset of CFFT. Its etiology was thought to be due to atheromatous plaque complication and hypercoagulable states. We experienced a longitudinally extensive CFFT secondarily generated following intravenous thrombolytic therapy. When reviewing the literature, there was only one other case of CFFT secondarily generated after intravenous thrombolytic therapy. Treatment options of CFFT include medical management and surgical and endovascular thrombectomy. In our case, mechanical thrombectomy was deferred due to an extremely high risk of embolism. Delayed endarterectomy after antithrombotic therapy resulted in a favorable clinical outcome. We report an extremely rare and successful case of longitudinally extensive CFFT, secondarily generated after intravenous thrombolytic therapy.