Commentary on a case report and literature review of acute carotid stent thrombosis

In this commentary on the article entitled“Acute carotid stent thrombosis:A case report and literature review”,the key points of the article are discussed.Acute carotid stent thrombosis(ACST)in the setting of carotid artery stenting(CAS)represents a rare but potentially catastrophic event.There is a wide range of treatment options available,including carotid endarterectomy,which is generally recommended for cases of refractory ACST.While there is no standard treatment regimen,dual antiplatelet therapy is typically recommended both before and after CAS to reduce risk of ACST.

Acute carotid stent thrombosis:A case report and literature review

BACKGROUND Acute carotid stent thrombosis(ACST)is a rare but devastating complication in the carotid artery stenting(CAS)procedure.The aim of this article is to report a case and review cases of ACST reported in the literature,and investigate risk factors and management strategies for ACST.CASE SUMMARY We reviewed the treatment process of a patient with ACST after CAS.Then multiple databases were systematically searched to identify studies reporting ACST from 2005 to 2020.The demographic data,risk factors,treatment strategies,and prognosis were extracted and analyzed.CONCLUSION The reason for ACST is multifactorial.Proper patient selection,normative antiplatelet treatment,and perfect technical detail may decrease the incidence of ACST.Several treatment strategies such as thrombolysis,mechanical thrombectomy,and open surgery may be options for the treatment of ACST.Limited data have shown that carotid endarterectomy is effective with favorable results.

Update on Carotid Stenting and Endarterectomy

The role of carotid stenting and endarterectomy has been evolving over the past few decades. Results of recent randomized trials have added more insights to the indications of the two established interventions for symptomatic moderate to severe stenosis as well as asymptomatic carotid stenosis. Despite a wide range of complication rates in various trials for both symptomatic and asymptomatic carotid stenosis, benefits of the two interventions have been consistently demonstrated for symptomatic moderate stenosis as well as asymptomatic severe stenosis albeit with lower benefit margin for asymptomatic disease. Intervention for asymptomatic carotid stenosis should only be considered when the complication rate can be maintained below 3%.

Intravascular ultrasonography assisted carotid artery stenting for treatment of carotid stenosis: Two case reports

BACKGROUND Digital subtraction angiography(DSA),the gold standard of cerebrovascular disease diagnosis,is limited in its diagnostic ability to evaluate arterial diameter.Intravascular ultrasonography(IVUS)has advantages in assessing stenosis and plaque nature and improves the evaluation and effectiveness of carotid artery sten-ting(CAS).CASE SUMMARY Case 1:A 65-year-old man presented with a five-year history of bilateral lower limb weakness due to stroke.Physical examination showed decreased strength(5-/5)in both lower limbs.Carotid artery ultrasound,magnetic resonance angiography,and computed tomography angiography(CTA)showed a right proximal internal carotid artery(ICA)stenosis(70%-99%),acute cerebral infarction,and severe right ICA stenosis,respectively.We performed IVUS-assisted CAS to measure the stenosis and detected a low-risk plaque at the site of stenosis prior to stent implantation.Post-stent balloon dilatation was performed and postoperative IVUS demonstrated successful expansion and adherence.CTA six months postoperatively showed no significant increase in in-stent stenosis.Case 2:A 36-year-old man was admitted with a right common carotid artery(CCA)dissection detected by ultrasound.Physical examination showed no positive neurological signs.Carotid ultrasound and CTA showed lumen dilation in the proximal CCA with an intima-like structure and bulging in the proximal segment of the right CCA with strip-like low-density shadow(dissection or carotid web).IVUS-assisted DSA confirmed right CCA dissection.CAS was performed and intraoperative IVUS suggested a large residual false lumen.Post-stent balloon dilatation was performed reducing the false lumen.DSA three months postoperatively indicated good stent expansion with mild stenosis.CONCLUSION IVUS aids decision-making during CAS by accurately assessing carotid artery wall lesions and plaque nature preoperatively,dissection and stenosis morphology intraoperatively,and visualizing and confirming CAS postoperatively.

Ultrasound-guided carotid angioplasty and stenting in a patient with iodinated contrast allergy:A case report

BACKGROUND Ischemic stroke is an entity with high incidence,morbidity,and mortality rates.Carotid artery stenosis is an important and independent risk factor for ischemic stroke.The three current approaches for treating carotid artery stenosis are drug treatment,carotid endarterectomy(CEA),carotid angioplasty and stenting(CAS).The approach is chosen based on the degree of stenosis.CEA or CAS could have been chosen for the current patient,who had severe carotid stenosis and an iodinated contrast allergy.After thoroughly communicating with the patient,the patient chose CAS for treatment.Therefore,we performed ultrasound-guided CAS to avoid the use of iodinated contrast.CASE SUMMARY The main symptoms of the patient were numbness and weakness of the left limb.Computed tomography angiography of the head and neck at another hospital indicated multiple sites of stenosis in the arteries of the head and neck.The patient requested CAS for treatment but was allergic to iodinated contrast media.Thus,routine digital subtraction angiography(DSA)with iodinated contrast could not be used for the procedure.The diagnosis of this patient was as follows:(1)Right parietal lobe cerebral infarction;(2)multiple sites of stenosis in the arteries of the head and neck(severe stenosis of the right internal carotid artery,severe stenosis of the right subclavian artery);(3)right subclavian steal syndrome;and(4)hypertension(stage 3,high risk).The interventions included routine treatment for cerebral infarction,oral administration of clopidogrel(75 mg qd)and aspirin(100 mg qd),ultrasound-guided CAS,and postoperative follow-up.Postoperative color Doppler ultrasound and cerebrovascular magnetic resonance angiography of the carotid artery showed good vascular recovery,and the postoperative follow-up indicated a good prognosis.CONCLUSION This case study suggests that ultrasound-guided endovascular treatment is a potential option for patients with contraindications to the iodinated contrast agents used in DSA-guided surgery,although excellent surgical operating skills are needed.

Relation between Carotid Artery Plaques Characteristics as a Predictor of Haemodynamics Changes after Carotid Artery Stenting

Objectives: To study relationship between carotid artery plaques characteristics and haemodynamic changes after carotid stenting. Patients and Methods: This observational prospective (pilot) study included 20 patients—who underwent CAS. The study was carried out in Ain shams university hospitals—Railway hospital (ERMED) and Suez insurance hospital from December 2018 to February 2020. Inclusion criteria, Symptomatic (defined as amaurosis fugax, TIA, Minor stroke or Major stroke) stenosis > 70%. Asymptomatic stenosis > 80% (accidentally discovered during pre-operative assessment for CABG and during full assessment for irrelevant stroke). Results: Regarding to plaque character for degree of stenosis, calcification and ulceration revealed significantly higher degree of stenosis in hemodynamic events group (P = 0.024). On the other hand, that there was no statistically significant difference between the two groups as regard calcification, ulceration and lesion location. Conclusion: The study revealed that HI is a common occurrence following CAS procedures and significantly higher degree of stenosis in hemodynamic events group. Plaque shape, ulcerations hardly affect haeodynamic instability after carotid stenting.

Monitoring cerebral ischemia during carotid endarterectomy and stenting

Current therapy for carotid stenosis mainly includes carotid endarterectomy and endovascular stenting,which may incur procedure-related cerebral ischemia.Several methods have been employed for monitoring cerebral ischemia during surgery,such as awake neurocognitive assessment,electroencephalography,evoked potentials,transcranial Doppler,carotid stump pressure,and near infrared spectroscopy.However,there is no consensus on the gold standard or the method that is superior to others at present.Keeping patient awake for real time neurocognitive assessment is effective and essential;however,not every surgeon adopts it.In patients under general anesthesia,cerebral ischemia monitoring has to rely on non-awake technologies.The advantageous and disadvantageous properties of each monitoring method are reviewed.

Evaluation of ischemic lesions after carotid artery stenting with diffusion-weighted imaging

BACKGROUND Almost 90%of cerebral thromboembolism cases are caused by atherosclerosis.Craniocervical atherosclerosis is often observed at the carotid bifurcation and is responsible for 20%-30%of all stroke cases.The course of atherosclerotic carotid artery stenosis varies depending on the grade of stenosis and characteristics of the plaque.Carotid artery stenting(CAS)can be used as a less invasive method in patients with symptomatic and asymptomatic high-grade carotid artery stenosis.Diffusion-weighted imaging(DWI)is an effective method for detection of silent or symptomatic acute ischemic lesions that may arise due to CAS or carotid endarterectomy.The number and volume of new ischemic lesions are determined using DWI.AIM To evaluate the number and volume of ischemic lesions and their cerebral parenchymal and vascular distribution after CAS using DWI.METHODS Forty-seven male(73.4%)and seventeen female(26.6%)patients(total,n=64)aged 42-84 years(mean 67.96±8.03 years)diagnosed with carotid stenosis between October 2006 and July 2012 were included in this retrospective study.Twelve of the cases(18.8%)were asymptomatic,while fifty-two(81.2%)were symptomatic.The area where the stenosis was highest was measured,and the stenosis rate was determined using the North American Symptomatic Carotid Endarterectomy Trial method.DWI of the cases was evaluated by two radiologists experienced in neuroradiology(B.A.with more than 15 years of experience,E.G.with more than 10 years of experience).Routine DWI examinations were carried out by a 1.5 T MR device 1 h before and after the operation.Since the ischemic lesions that developed in the first hour and in the follow-up period of 5-24 h were assumed to be due to CAS,all lesions within the first 24 h were considered as new ischemias.RESULTS In the present study,39 new ischemic lesions were detected in 20 cases.The average number of new lesions after all CAS operations was 0.62.They were mostly located in the occipital lobes,followed by the frontal and parietal lobes.These new ischemic lesions were most common in the middle cerebral artery territory,followed by the posterior cerebral artery territory and middle cerebral artery-posterior cerebral artery watershed areas.New lesions were found in 31.2%(20/64)of patients,including 17(26.5%)in ipsilateral and three(4.6%)in contralateral hemispheres.New bilateral lesions were detected in one case(1.5%).The average volume of the new ischemic lesions detected by the two observers was 1.10 cm³.The numbers of newly appearing ischemic lesions in DWI after CAS were significantly higher in cases where stenting was applied on the left side of the carotid artery and in cases where longer plaques(>1 cm)were responsible for the narrowing in symptomatic patients.The stenosis rate was low in the group with ulcerated plaques.CONCLUSION New ischemic lesions due to CAS appear mostly in the main arterial territory but they may also occur in watershed areas.

Short-term results of carotid stenting for the treatment of extracranial carotid occlusive disease

Carotid artery angioplasty and stenting （CAS） has been performed with increasing frequency for the treatment of extracranial carotid occlusive diseases （ECOD） in recent years. Its feasibility and safety are supported by the Stenting and Angioplasty with Protection in Patient at High Risk for Endarterectomy （SAPPHIRE） trial,1 which revealed a lower incidence of death, stroke and myocardial infarction compared with carotid endarterectomy （CEA） in high-risk patients. However, it is a pity that up to now, initial results of this endovascular procedure have yet been infrequently documented in China. This retrospective study was to analyze the short-term results of CAS to treat ECOD in a single medical center.

Carotid artery stenting versus carotid endarterectomy in the treatment of symptomatic and asymptomatic carotid stenosis: a systematic review and meta-analysis

Purpose: To evaluate the short-term and intermediate-to long-term efficacy and safety of carotid artery stenting(CAS) compared with carotid endarterectomy(CEA). Materials and Methods: The published literature was electronically searched for randomized controlled trials(RCTs) between CAS and CEA for the treatment of carotid stenosis performed from January 2000 to January 2017. The short-term and intermediate-to long-term outcomes were evaluated. Results: We identified 10 RCTs including 7,183 participants with symptomatic or asymptomatic carotid stenosis. Our meta-analysis found different results between the patients with and those without symptoms. In patients with symptomatic carotid stenosis, the total stroke incidence in the CAS group was significantly higher than that in the CEA group within the 30-day periprocedural period(p<0.001); however, the myocardial infarction incidence in the CAS group was significantly lower than that in the CEA group(p<0.05). There was no significant difference between the two groups in the mortality within 30 days post-procedure, but the intermediate-to long-term incidence of stroke or death in the CAS group was higher than that of the CEA group(p<0.05). In contrast, for asymptomatic patients, there were no significant differences between the CAS and CEA groups in the short-and intermediate-to long-term outcomes. Conclusion: For patients with symptomatic carotid stenosis, CEA is associated with an increased risk of myocardial infarction, whereas CAS is correlated with an increased risk of procedurally related strokes. However, for patients with asymptomatic carotid stenosis, no significant difference was found in the efficacy or safety between CAS and CEA.

Percutaneous cervical carotid artery access with stenting of the left internal carotid artery in an elderly patient

To describe the successful endovascular treatment in a nonagenarian with symptomatic internal carotid artery stenosis using direct carotid artery access. An independent 98 year-old man was admitted to our hospital for symptoms of progressive weakness with disorientation and dysphasia. Carotid Duplex ultrasonography was performed which revealed a totally occluded right internal carotid artery and high grade stenosis of the left internal carotid artery by velocities of 608/240 cm/sec. The patient refused surgical endarterectomy and thus he was referred for carotid artery stenting. Using the femoral artery approach and multiple catheter techniques, access to the common carotid artery could not be accomplished safely. The procedure was aborted and he was therefore brought back to the catheterization laboratory the following day for direct carotid access. Carotid artery stenting was accomplished by using of a 6F sheath percutaneously in the left common carotid, cerebral protection device (CPD) and a Nitinol stent. The patient was discharged the following day without complications. At 14 months follow-up the patient is functional and independent without recurrence of symptoms. Carotid artery stenting via direct access can be accomplished in patients when the femoral artery approach is anatomically prohibitive. In this case of advanced age and the patient’s refusal for surgery, direct carotid access was his only option.

Evaluation of changes of intracranial blood flow after carotid artery stenting using digital subtraction angiography flow assessment

AIM: To evaluate the changes of intracranial blood flow after carotid artery stenting(CAS), using the flow assessment application "Flow-Insight", which was developed in our department.METHODS: Twenty patients treated by CAS participated in this study. We analyzed the change in concentration of the contrast media at the anterior-posterior and profile view image with the flow assessment application "Flow-Insight". And we compared the results with N-isopropyl-p-[123I] iodoamphetamine-single-photon emission computed tomography(IMP SPECT) performed before and after the treatment. RESULTS: From this study, 200% of the parameter "blood flow" change in the post/pre-treatment is suggested as the critical line of the hyperperfusion syndrome arise. Although the observed blood flow increase in the digital subtraction angiography system did not strongly correlate with the rate of increase of SPECT, the "Flow-Insight" reflected the rate of change of the vessels well. However, for patients with reduced reserve blood flow before CAS, a highly elevated site was in agreement with the site analysis results. CONCLUSION: We concluded that the cerebral angiography flow assessment application was able to more finely reveal hyperperfusion regions in the brain after CAS compared to SPECT.

Plaque components affect wall stress in stented human carotid artery: A numerical study

Carotid artery stenting presents challenges of in-stent restenosis and late thrombosis, which are caused primarily by alterations in the mechanical environment of the artery after stent implantation. The present study constructed patient-specific carotid arterial bifurcation models with lipid pools and calcified components based on magnetic resonance imaging. We numerically analyzed the effects of multicomponent plaques on the distributions of von Mises stresses (VMSs) in the patient-specific models after stenting. The results showed that when a stent was deployed, the large soft lipid pool in atherosclerotic plaques cushioned the host artery and reduced the stress within the arterial wall; however, this resulted in a sharp increase of VMS in the fibrous cap. When compared with the lipid pool, the presence of the calcified components led to slightly increased stresses on the luminal surface. However, when a calcification was located close to the luminal surface of the host artery and the stenosis, the local VMS was elevated. Overall, compared with calcified components, large lipid pools severely damaged the host artery after stenting. Furthermore, damage due to the calcified component may depend on location.

Transcervical access,reversal of flow and mesh-covered stents:New options in the armamentarium of carotid artery stenting

In the last 25 years, the very existence of carotid artery stenting(CAS) has been threatened on a number of occasions. The initial disappointing results that even lead to the discontinuation of an early randomized controlled trial have improved considerably with time. Novel devices, advanced stent and equipment technology, alternative types of access and several types of filters/emboli protecting devices have been reported to reduce stroke/death rates during/after CAS and improve CAS outcomes. The present review will provide a description of the various technology advances in the field that aim to reduce stroke and death rates associated with CAS. Transcervical access, reversal of flow and mesh-covered stents are currently the most promising tools in the armamentarium of CAS.

Carotid artery stenting in the elderly: the time has come

Introduction Affecting over half a million people per year, stroke is the third leading cause of death in the United States. Approximately 30% of strokes are caused by carotid occlusive disease.……

Ileal hemorrhagic infarction after carotid artery stenting:A case report and review of the literature

BACKGROUND Ileal hemorrhagic infarction after carotid artery stenting(CAS)is a fatal complication.The prognosis of ileal hemorrhagic infarction after CAS is very poor if not treated in a timely manner.We describe a rare case of ileal hemorrhagic infarction due to acute embolism of the mesenteric artery after CAS.CASE SUMMARY A 67-year-old man with acute ischemic stroke underwent CAS via the right femoral artery approach 21 d after intensive medical treatment.On the first day after surgery,the patient had abdominal distension and abdominal pain.Abdominal enhanced computed tomography revealed intestinal obstruction,severe stenosis of the superior mesenteric artery,and poor distal angiography.An exploratory laparotomy was performed,and pathological examination showed hemorrhagic ileal infarction.It was subsequently found that the patient had intestinal flatulence.With the guidance of an ultrasound scan,the patient underwent abdominal puncture,drainage,and catheterization.After 58 d of treatment,the patient was discharged from hospital with a National Institutes of Health Stroke Scale score of 2 points,and a Modified Rankin Scale score of 1 point.At the 6-mo follow-up,the patient had an excellent functional outcome without stroke or mesenteric ischemia.Furthermore,computed tomography angiography showed that the carotid stent was patent.CONCLUSION Ileal hemorrhagic infarction is a fatal complication after CAS,usually caused by mesenteric artery embolism.Thus,more attention should be paid to the complications of embolism in the vascular system as well as the nervous system after CAS,and the complications should be identified and treated as early as possible.

Efficacy of Different Types of Self-expandable Stents in Carotid Artery Stenting for Carotid Bifurcation Stenosis

Both open and closed loop self-expandable stents were used in carotid artery stenting（CAS） for carotid bifurcation stenosis. We sought to compare the efficacy of two types of stents in CAS. The data of 212 patients treated with CAS（42 and 170 cases implanted with closed and open loop stents, respectively） for carotid bifurcation stenosis and distal filtration protection devices were retrospectively analyzed. Between closed and open loop stents, there were no significant differences in hospitalization duration, NIHSS score before and after the treatment, stenosis at 12 th month, and cumulative incidence of primary endpoint events within 30 days or from the 31 st day to the 12 th month; while there were significant differences in hemodynamic changes and rate of difficulty in recycling distal filtration protection devices. Use of open vs. closed loop stents for carotid bifurcation stenosis seems to be associated with similar incidence of complications, except for greater rate of hemodynamic changes and lower rate of difficulty in recycling the distal filtration protection devices.

Effect of Carotid Artery Stenting and Extracranial-Intracranial By-Pass on Cognitive Function: Preliminary Results

Background: To compare the neuropsychological consequences after carotid artery stenting (CAS) and extracranial-intracranial by-pass (EC-IC by-pass). Methods: A total of 43 patients referred to CAS, 32 patients referred to EC-IC by-pass and 43 control subjects were enrolled in the study. Neuropsychologic testing was performed before and three months after procedure. A paired Student t test was used to compare neuropsychologic test scores at baseline and three months after procedure in each group. Cognitive changes in a three-month follow-up were not normally distributed and compared among/between groups with Kruskal-Wallis test. Results: Three months after the treatment both the CAS and EC-IC by-pass groups showed improved cognitive performance compared to baseline, whereas the same improvement wasn’t seen in the control group. The scores from Activities of Daily Living also improved in all three groups in a three-month follow-up, and EC-IC group presented a more distinct increase in daily life abilities comparing to the other two groups. Conclusions: CAS and EC-IC by-pass in patients with a carotid or intracranial stenosis may result in cognitive improvement three months after surgery.

Evaluation of the Protégé^(TM) stent in the treatment of carotid artery stenosis with adjunctive use of a filter Embolic Protection Device (PROCAR)-one-month follow-up data on 77 patients

Objective The trial was designed to evaluate the safety and performance of the ev3 Protégé TM stent in the treatment of de novo or re-stenotic common and/or internal carotid artery stenoses with adjunctive use of a CE-marked filter embolic protection device.Methods This study was a prospective multi-center, single-arm trial. Between June and October 2003, 77 patients were enrolled in 8 investigational centers throughout Europe. The primary endpoint was the incidence of Major Neurological Events (MANE) through one month. Other endpoints were the ability to properly place the stent, and primary patency and MANE after six months. Eligible for the study were patients with a de novo or restenotic target lesion located in the common and/or internal carotid artery (>70% stenosis for asymptomatic and >50% stenosis for symptomatic patients). The ev3 Spider (Embolic Protection Filter was used in 75 of 77 cases. Results In 76 out of the 77 patients (99%), the stent could be successfully implanted with a residual stenosis ≤30% as criterion. Of the 74 patients that had a carotid ultrasound at one month follow-up, none had a re-stenosis of the target lesion. There were three MANEs during or immediately after the procedure (3.9%), two were major and one was a minor stroke. There were eight severe complications (9.1%); six of these happened during or immediately after the procedure and were related to the procedure, none was related to the device. They are resolved without sequelae. No deaths have occurred.Conclusions The Protégé stent is safe and performs well in the treatment of carotid artery stenosis. The technical success rate for placement of the Protégé stent as assessed by the residual stenosis post implant was very high and all stents were successfully deployed. The incidence of MANE was comparable with that in other recent carotid stent studies and still lower than standard CEA.

A Comprehensive Analysis of a Case of Internal Carotid Artery Stenting

With the development of science and technology and the continuous progress of interventional equipment,internal carotid artery stenting has become increasingly popular among patients in view of its advantages,which include high efficiency,minimally invasive,and fast postoperative recovery.It has grown importance as a surgical method for the treatment of severe internal carotid artery stenosis.This paper discusses a rare case of severe internal carotid artery stenosis and its management,where various types of pre-dilatation balloons were not able to be positioned in the stenting process.Relevant solutions have also been proposed in hope to provide a more theoretical and practical basis for clinical work.