Early acute hemispheric stroke after carotid endarterectomy. Pathogenesis and management

Stenting for subclavian steal phenomenon to restore cerebral perfusion due to acute carotid occlusion following carotid endarterectomy: a case report

BACKGROUND

Perioperative symptomatic carotid artery occlusion after carotid endarterectomy is a rare complication. In this study, we present a case of symptomatic acute carotid artery occlusion that occurred after carotid endarterectomy in a patient with coexistent subclavian artery steal phenomenon, which was successfully treated with subclavian artery stenting.

CASE PRESENTATION

A 57-year-old East Asian female presented with stenosis in the left common carotid artery and left subclavian artery along with subclavian steal. The proximal segment of the left anterior cerebral artery was hypoplastic, and the posterior communicating arteries on both sides were well-developed. Left internal carotid artery stenosis progressed during the follow-up examination; therefore, left carotid endarterectomy was performed. On the following day, symptoms of cerebral perfusion deficiency appeared due to occlusion of the left carotid artery. The stenotic origin of the left common carotid artery and the suspected massive thrombus in the left carotid artery posed challenges to carotid revascularization. Therefore, left subclavian artery stenting for the subclavian steal phenomenon was determined to be the best option for restoring cerebral blood flow to the whole brain. Her symptoms improved after the procedure, and the postprocedural workup revealed improved cerebral blood flow.

CONCLUSION

Subclavian artery stenting is safe and may be helpful in patients with cerebral perfusion deficiency caused by intractable acute carotid occlusion coexisting with the subclavian steal phenomenon. Revascularization of asymptomatic subclavian artery stenosis is generally not recommended. However, cerebral circulatory insufficiency as a comorbidity may be worth considering.

Intraoperative Computed Tomography Angiography: A Novel Completion Imaging Modality for Carotid Endarterectomy

BACKGROUND

Intraoperative computed tomography angiography (ICTA) is a novel completion imaging modality for carotid endarterectomy (CEA). No studies exist in the literature describing ICTA use in CEA.

OBJECTIVE

To evaluate the feasibility and efficacy of ICTA as a method of immediately evaluating the technical results of CEA.

METHODS

Twenty-three consecutive CEAs were performed by a single neurosurgeon over an 8-month period. Of this series, 12 utilized ICTA for completion imaging, 10 utilized duplex ultrasonography (US), and 1 utilized no intraoperative completion imaging. Electronic medical records were reviewed to assess demographics, CTA results, US results, and need for revisions.

RESULTS

Patients included 13 men (62%) and 8 women (38%). All patients had symptomatic internal carotid artery stenosis. Polytetrafluoroethylene (PTFE) patch angioplasty was used in 16 cases (70%). Average operative times were comparable between cases that utilized CTA and US, 180 and 175 min, respectively. Major technical defects were identified in one of the 12 cases utilizing ICTA and none of the 10 cases utilizing intraoperative US. The technical defect was revised without subsequent neurological complication. One patient had a postoperative intracerebral hemorrhage requiring surgical evacuation. Fifteen patients were followed for up to 3 months with no postoperative stroke or transient ischemic attacks.

CONCLUSION

ICTA is a potentially safe and effective completion imaging modality compared to traditional alternatives, enabling the identification of technical deficits intraoperatively. While no statistically significant difference in operative times were noted between intraoperative CTA and US use, numerous steps must be taken to maximize the efficiency of ICTA.

Perioperative stroke after carotid endarterectomy: etiology and implications

BACKGROUND

Carotid endarterectomy (CEA) is the procedure of choice for reducing the risk of stroke in both symptomatic and asymptomatic carotid artery stenoses. Stroke is associated with significant morbidity and mortality peri-operatively (2-3 %). Our primary aim is to evaluate the etiology of these strokes after CEA and their impact on morbidity by comparing the length of stay in the hospital.

METHODS

A total of 584 patients with documented neurological status evaluations who underwent CEAs were included in the study. Neurophysiological monitoring data was obtained during CEA for carotid stenosis included eight-channel electroencephalography (EEG) and upper extremity somatosensory evoked potentials (SSEPs).

RESULTS

Twenty-one (3.595 %) patients had strokes in the perioperative period and they were more likely to have left-sided surgery (p = 0.008), intraoperative monitoring (IOM) changes (p < 0.001), an intraoperative shunt placed (p = 0.0002) or a hospital stay longer than 5 days (p = 0.0042). Unilateral anterior circulation ischemic stroke were the most common in our series. In a logistic regression model, left-sided surgery was shown to be 4.78 times more likely to be associated with perioperative stroke (1.50-15.27; p = 0.008) while intraoperative shunts were 11.85 times more likely to have strokes (3.97-35.34; p < 0.0001). Patients with stenosis greater than 70 % were 6.67 times less likely to have a stroke (0.04-0.59; p = 0.007).

CONCLUSIONS

Ischemic anterior circulation strokes are the most common type of post-operative neurological changes in patients undergoing CEA. Intraoperative shunt placement was a strong predictor of perioperative strokes. Since shunts are only placed following intraoperative monitoring changes, SSEPs and EEG can therefore function as a biomarker of cerebral hypo-perfusion.

Acute stroke after carotid endarterectomy: time for a paradigm shift? Multicenter experience with emergent carotid artery stenting with or without intracranial tandem occlusion thrombectomy

BACKGROUND

Stroke in the immediate postoperative period after carotid endarterectomy is a rare complication. Many centers have begun incorporating angiography before surgical re-exploration, which has the advantage of confirming carotid occlusion and treating tandem intracranial lesions if present.

OBJECTIVE

To determine the safety and efficacy of this strategy.

METHODS

A retrospective review was performed of all patients undergoing acute stenting of the carotid artery after carotid endarterectomy from November 2009 to June 2013 at 4 centers. Charts and angiographic images were reviewed. Eleven cases of carotid thrombosis within 72 hours of carotid endarterectomy and subsequent treatment strategies are summarized.

RESULTS

All patients had >50% carotid stenosis before carotid endarterectomy. One patient had intraoperative occlusion and dissection of the internal carotid artery, which was noted on intraoperative carotid duplex ultrasound. All patients underwent postoperative computed tomography or computed tomography perfusion scans with subsequent cerebral angiography and stent reconstruction within 11 hours of symptom onset. In all cases, carotid recanalization was successfully completed between 32 and 160 minutes from groin puncture. There were no procedural complications. Four patients had a tandem middle cerebral artery occlusion, 3 of whom underwent successful recanalization.

CONCLUSION

Emergent endovascular evaluation in the setting of acute post--carotid endarterectomy thrombosis is a safe and timely treatment option, with the benefit of detecting and treating embolic intracranial lesions. Immediate angiography and intervention in this rare surgical complication show promising initial results.

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

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.

Low-dose GYKI-52466: prophylactic preconditioning confers long-term neuroprotection and functional recovery following hypoxic-ischaemic brain injury

Experimental preconditioning provides beneficial outcomes in conditions such as cardiac surgery, brain surgery and stroke. Here we evaluated the protective effects of low-dose subcutaneous GYKI-52466 preconditioning in a rat model of hypoxic-ischaemic (HI) brain injury. Male Sprague-Dawley rats (postnatal day 26) were administered saline or GYKI-52466 (GYKI; 3-mg/kg, 90 min; 1-mg/kg, twice in 120 min; or 0.5-mg/kg, thrice in 180 min) prior to left common carotid artery occlusion. Animals were allowed to recover for 2h, and then placed in a hypoxia chamber (8% O₂/92% N₂; 33 ± 1°C) for 1h. A sham surgery group received saline without HI. Seizure activity was scored during hypoxia and sensorimotor tests performed before surgery and at 1, 7, 14 and 90 days post-HI. On days 14 and 90 brains were fixed and sectioned for the assessment of infarct size and ventricular enlargement. Low-dose GYKI-52466 preconditioning significantly reduced infarct volume and ventricular enlargement relative to saline-treated controls at day 14 after HI. On day 90, tissue loss was significantly reduced by GYKI 3-mg/kg compared to saline. Foot-faults, paw use asymmetry, and postural reflex scores were significantly improved in all GYKI treatment groups. Our results show that GYKI-52466 is effective at doses well-below, and at pre-administration intervals well-beyond previous studies, and suggest that a classical blockade of ionotropic AMPA receptors does not underlie its neuroprotective effects. Low-dose GYKI-52466 preconditioning represents a novel, prophylactic strategy for neuroprotection in a field almost devoid of effective pharmaceuticals.