64-detector CT angiography within 24 hours after carotid endarterectomy and correlation with postoperative stroke

Abstract

W hile carotid endarterectomy (CEA) is a wellestablished treatment for patients with carotid stenosis, 2,11,21 it is associated with a small but not insignificant rate (3.9%-6.5%) of perioperative stroke/transient ischemic attack (TIA). 9,16 This can necessitate urgent postoperative neuroimaging of the brain and supplying vasculature. Imaging findings associated with ischemic/hemorrhagic stroke 3,5,18,26 and hyperperfusion syndrome 12 after CEA are well reported, as are arterial changes (days to weeks) 8,19 and restenosis (months to years) 6,7,10,17 after CEA. However, there are few studies examining the carotid artery within the early 24-hour period following CEA (during which more than 75% of perioperative strokes occur), 9 and, to our knowledge, all have relied upon duplex ultrasound. obJect Carotid endarterectomy (CEA) carries a small but not insignificant risk of stroke/transient ischemic attack (TIA), most frequently observed within 24 hours of surgery, which can lead to the need for urgent vascular imaging in the immediate postoperative period. However, distinguishing expected versus pathological postoperative changes may not be straightforward on imaging studies of the carotid artery early after CEA. The authors aimed to describe routine versus pathological anatomical findings on CTA performed within 24 hours of CEA, and to evaluate associations between these CTA findings and postoperative stroke/TIA. methods The authors reviewed 113 consecutive adult patients who underwent postoperative CTA within 24 hours of CEA at a single academic institution. Presence and location of arterial "flaps," luminal "step-off," intraluminal thrombus and hematoma were documented from postoperative CTA scans. Medical records were reviewed to determine the incidence of new postoperative neurological findings. results Postoperative CTA findings included common carotid artery (CCA) step-off (63.7%), one or more intraarterial flaps (27.4%), hematoma at the surgical site (15.9%), and new intraluminal thrombus (7.1%). Flaps were seen in the external carotid artery (ECA), internal carotid artery (ICA), and CCA in 18.6%, 9.7%, and 6.2% of patients, respectively. New postoperative neurological findings were present in 7.1% of patients undergoing CTA. Flaps (especially ICA/CCA) and/ or intraluminal thrombi were more frequently seen in patients undergoing CTA for new postoperative stroke/TIA (85.7%) versus patients undergoing CTA for routine postoperative imaging (14.3%, p = 0.002). coNclusioNs CTA within 24 hours of CEA demonstrates characteristic anatomical findings. CCA step-offs and ECA flaps are relatively common and clinically insignificant, whereas ICA/CCA flaps and thrombi are less frequently seen and are associated with postoperative stroke/TIA.