Recanalization of a Symptomatic Extracranial Internal Carotid Artery Near Occlusion with Proximal and Distal Protection

Subacute endovascular recanalization of symptomatic cerebral artery occlusion: a propensity score-matched analysis

BACKGROUND

The interval between the onset of cerebral vessel occlusion and recanalization has been shown to be an independent predictor of poor outcomes. However, endovascular recanalization of symptomatic cerebral vessel occlusion in the subacute period has not been well documented. We investigated the safety and efficacy of subacute recanalization of occluded cerebral vessels in patients with ischemic stroke or transient ischemic attacks (TIAs).

METHODS

Between 2014 and 2015, 98 patients were admitted to the emergency room for ischemic stroke or TIA with a small infarct core, which was defined as modest early ischemic change on non-contrast CT or overt diffusion-perfusion mismatch. All patients underwent pre-transfemoral cerebral angiography and post-endovascular treatment. The patients were classified according to acute (onset-to-groin puncture time ≤6 hours) or subacute (onset-to-groin puncture time >6 hours) recanalization. Using propensity score analysis, recipients of acute and subacute recanalization underwent 1:1 matching.

RESULTS

Following 1:1 propensity score matching, 32 patients who underwent acute and 32 who underwent subacute intra-arterial thrombolysis were matched. There were no significant differences in National Institutes of Health Stroke Scale at discharge, modified Rankin scale (mRS), the proportion of patients with an mRS value of 0-2, mortality at discharge, intracerebral bleeding, postprocedural infarct extension, newly detected infarction, and hyperintense acute reperfusion marker on follow-up images between the acute and subacute recanalization groups.

CONCLUSIONS

In selected patients with clinically unstable cerebral artery occlusions, a diffusion-perfusion mismatch and small CT lesions, subacute and acute recanalization has comparable safety and efficacy rates.

Carotid Near-Occlusion: A Comprehensive Review, Part 1--Definition, Terminology, and Diagnosis

Carotid near-occlusion is distal ICA luminal collapse beyond a tight stenosis, where the distal lumen should not be used for calculating percentage stenosis. Near-occlusion with full ICA collapse is well-known, with a threadlike lumen. However, near-occlusion without collapse is often subtle and can be overlooked as a usual severe stenosis. More than 10 different terms have been used to describe near-occlusion, sometimes causing confusion. This systematic review presents what is known about carotid near-occlusion. In this first part, the foci are definition, terminology, and diagnosis.

Symptomatic carotid near-occlusion with full collapse might cause a very high risk of stroke

BACKGROUND

The risk of early stroke recurrence amongst patients with symptomatic carotid near-occlusion with and without full collapse is unknown. Therefore, the aim of this study was to analyse the 90-day risk of recurrent ipsilateral ischaemic stroke in patients with symptomatic carotid near-occlusion both with and without full collapse.

METHODS

This study was a secondary analysis of the Additional Neurological SYmptoms before Surgery of the Carotid Arteries: a Prospective study (ANSYSCAP). We prospectively analysed 230 consecutive patients with symptomatic 50-99% carotid stenosis or near-occlusion. Based on the combination of several imaging modalities, 205 (89%) patients were classified as having 50-99% carotid stenosis, and 10 (4%) and 15 (7%) as having near-occlusion with and without full collapse, respectively. The 90-day risk of recurrent ipsilateral ischaemic stroke was compared between these three groups. Only events that occurred before carotid endarterectomy were analysed.

RESULTS

The 90-day risk of recurrent stroke was 18% [95% confidence interval (CI) 12-25%; n = 29] for patients with 50-99% carotid stenosis, 0% for patients with near-occlusion without full collapse and 43% (95% CI 25-89%; n = 4) for patients with near-occlusion with full collapse (P = 0.035, log-rank test). The increased risk of recurrent ipsilateral ischaemic stroke for patients with symptomatic near-occlusion with full collapse remained significant after multivariable adjustment for age, sex and type of presenting event.

CONCLUSIONS

Patients with symptomatic carotid near-occlusion with full collapse might have a very high risk of stroke recurrence. Carotid endarterectomy could be considered for these patients.

Reduction in distal emboli with proximal flow control during mechanical thrombectomy: a quantitative in vitro study

BACKGROUND AND PURPOSE

To evaluate the impact of proximal flow control on efficacy and safety of mechanical thrombectomy in an in vitro middle cerebral artery occlusion.

METHODS

Three independent variables, including clot type, device (Merci Retriever, Solitaire FR, and Trevo devices), and use of a balloon guide catheter, were used to ascertain the impact of proximal flow control on the size and number of distal emboli generated during thrombectomy. Secondary end points were the recanalization rate and amount of flow restored.

RESULTS

Use of the balloon guide catheter during thrombectomy of the fragile, hard clot significantly reduced the formation of large distal emboli with a diameter >1 mm, regardless of the device used (P<0.01). Applying aspiration via the balloon guide catheter in place of the conventional guide catheter resulted in a significant increase of flow reversal (P<0.0001). Prior to thrombectomy, deployment of the stent-trievers produced immediate flow restoration through the soft and hard clot occlusions, 69.2 ± 27.3 and 45.5 ± 22.8 mL/min, respectively, that was preserved after the balloon inflation because of collateral flow via the posterior communication artery. After deployment but before thrombectomy, no flow was restored when using the Merci Retriever. After thrombectomy, complete flow restoration was achieved in a majority of cases. The Merci Retriever required more thrombectomy attempts to achieve hard clot removal compared with the stent-trievers when the conventional guide catheter was used (1.5 versus 1.1).

CONCLUSIONS

The risk of distal embolization was significantly reduced with the use of the balloon guide catheter.

External Carotid Artery Stenting to Treat Patients With Symptomatic Ipsilateral Internal Carotid Artery Occlusion

BACKGROUND

The external carotid artery (ECA) anastomoses in many distal territories supplied by the internal carotid artery (ICA) and is an important source of collateral circulation to the brain. Stenosis of the ECA in ipsilateral ICA occlusion can produce ischemic sequelae.

OBJECTIVE

To examine the effectiveness of ECA stenting in treating symptomatic ipsilateral ICA occlusion.

METHODS

We retrospectively reviewed patient databases from 5 academic medical centers to identify all individuals who underwent ECA stenting after 1998. For all discovered cases, coinvestigators used a common submission form to harvest relevant demographic information, clinical data, procedural details, and follow-up results for further analysis.

RESULTS

Twelve patients (median age, 66 years; range, 45–79 years) were identified for our cohort. Vessel disease involvement included severe ECA stenosis ≥ 70% in 11 patients and ipsilateral ICA occlusion in all patients. Presenting symptoms included signs of transient ischemic attack, stroke, and amaurosis fugax. ECA stenting was associated with preservation of neurological status in 11 patients and resolution of symptoms in 5 patients at a median follow-up time of 26 months (range, 1–87 months; mean, 29 months). Symptomatic in-stent restenosis did not occur within any patient during the follow-up course.

CONCLUSION

We found ECA stenting in symptomatic ipsilateral ICA disease to be a potentially effective strategy to preserve neurological function and to relieve ischemic symptoms. Further investigation with larger studies and longer follow-up periods is warranted to elucidate the true indications of this management strategy.

Chronic total symptomatic carotid artery occlusion treated successfully with stenting and angioplasty

OBJECTIVE AND IMPORTANCE

Treatment of symptomatic chronic totally occluded carotid artery has been limited to medical management. An ongoing clinical trial is examining the role of extracranial to intracranial bypass surgery in select patients with impaired cerebrovascular reserve based on PET imaging parameters. We describe a case utilizing stenting and angioplasty to treat a chronic total carotid occlusion as a potential alternative therapy.

CLINICAL PRESENTATION

A 55-year-old woman presented with a right hemispheric ischemic stroke in the setting due to a right internal carotid artery total occlusion.

INTERVENTION

She was treated medically with antiplatelet therapy and oral vasopressor agents. She returned with new symptoms 1 month later and was successfully treated with stenting and angioplasty. At the 9-month follow-up, she remains neurologically intact.

CONCLUSION

Stenting and angioplasty may be a therapeutic option in select patients with chronic total carotid occlusion. Further study is required to determine the safety profile of this treatment modality.