"Internal cross-clamping" for symptomatic internal carotid artery thrombus. Report of two cases.

Both carotid endarterectomy and carotid artery stent placement with filter embolic protection present a higher risk for patients with internal carotid artery (ICA) lesions containing intraluminal thrombus. Despite the risk associated with intervention, patients with symptomatic intraluminal thrombus who were enrolled in the North American Symptomatic Endarterectomy Trial did better with surgical than medical treatment. We describe the novel use of an endovascular "internal cross-clamping" technique in two patients with symptomatic intraluminal thrombus in the ICA. A 57-year-old woman presented with a history of multiple episodes of left upper-extremity numbness, mild dysarthria, and agraphia occurring over the previous 24 hours. Cranial magnetic resonance imaging revealed a scattered watershed infarction of the right hemisphere and a critical stenosis of the right ICA. An 81-year-old man awoke with hemiplegia and inability to follow commands after undergoing a complicated carotid endarterectomy. Computed tomographic perfusion imaging demonstrated an increased time to peak in the left middle cerebral territory, and emergent angiography demonstrated both intimal flaps and thrombus in the endarterectomy bed. The lesions in both patients were treated with endovascular stent placement using both proximal and distal flow occlusion--a functional "internal cross-clamping"--for embolic protection. To our knowledge, this is the first report of internal trapping and stent placement for symptomatic carotid stenosis containing intraluminal thrombus. This treatment strategy should be added to the armamentarium of endovascular surgeons in selected patients with symptomatic carotid intraluminal thrombus.