Feasibility of carotid artery stenting in patients with angiographic string sign

Background : Treatment of angiographic string sign (SS) of the carotid artery with carotid endarterectomy or carotid artery stenting (CAS) has been associated with a high incidence of periprocedural neurological events. We describe our experience with CAS in a case series of symptomatic patients with severe carotid stenosis and angiographic SS. Methods : We performed a retrospective review from 1999 to 2009 using our cardiac cath laboratory database and identified nine patients with the angiographic SS who underwent CAS. All patients were referred for carotid angiography by a neurologist due to symptoms (stroke or transient ischemic attack (TIA)). All lesions were predilated and treated with self‐expanding stents. Distal protection devices were utilized (six patients) once they became available. Periprocedural outcomes and long‐term follow‐up was reviewed when available. Results : The average time from onset of symptoms to CAS was 45 days. All CAS procedures were technically and clinically successful without acute complications. One year follow‐up was available in eight patients. One patient had a possible TIA, and the remaining seven patients did not report any events (death, stroke, TIA or myocardial infarction). Carotid ultrasound evaluation at 12 months was available in six patients and showed no evidence of restenosis. Conclusions : In our experience, CAS in patients with severe symptomatic carotid stenosis and angiographic SS is feasible, with an acceptably low periprocedural complication rate. © 2010 Wiley‐Liss, Inc.     

An evidence‐based review of the impact of periprocedural myocardial infarction in carotid revascularization

Landmark trials comparing carotid endarterectomy (CEA) with medical therapy in patients with symptomatic or asymptomatic atherosclerotic stenosis of extracranial carotid arteries have favored carotid revascularization. Carotid artery stenting (CAS) has emerged as a minimally invasive option for revascularization of carotid artery stenoses and has been shown to be noninferior to CEA, regardless of patient symptom status. Debate continues regarding the importance of periprocedural myocardial infarction (PMI) as an endpoint in carotid revascularization trials. Recent randomized comparisons of CEA and CAS pre‐specify PMI as an endpoint. Understanding PMI in CEA and CAS, the need for routine biomarker assessment surrounding both revascularization strategies, the effect of PMI on long‐term morbidity and mortality, and the groups most at risk for PMI are of critical importance when choosing a carotid revascularization strategy for symptomatic and asymptomatic patients, since decreasing the incidence of PMI will make revascularization safer. This review examines available data regarding the relevance of PMI in vascular and carotid‐specific outcomes. © 2013 Wiley Periodicals, Inc.     

Neuroprotection during carotid artery stenting using the GORE flow reversal system: 30‐day outcomes in the EMPiRE Clinical Study

Background : Each of the embolic protection devices used in carotid artery stenting (CAS) has advantages and disadvantages. The prospective, multicenter, single‐arm EMPiRE Clinical Study investigated a proximally placed device (GORE Flow Reversal System) that provides distal neuroprotection during CAS by reversing blood flow in the internal carotid artery, thereby directing emboli away from the brain. Methods : The study evaluated 30‐day outcomes in 245 pivotal high‐surgical‐risk patients (mean age, 70 years; 32% symptomatic; 16% ≥80‐years old) with carotid stenosis who underwent CAS using the flow reversal system. The primary endpoint was a major adverse event (MAE; stroke, death, myocardial infarction, or transient ischemic attack) within 30 days of CAS. The MAE rate was compared with an objective performance criterion (OPC) derived from CAS studies that included embolic protection. Results : The MAE rate was 4.5% (11 patients; P = 0.002 compared with the OPC). The stroke and death rate was 2.9%. No patient had a major ischemic stroke. Six patients (2.4%) had intolerance to flow reversal. The death and stroke rates in the symptomatic, asymptomatic, and octogenarian subgroups were 2.6, 3, and 2.6%, respectively, meeting American Heart Association guidelines for carotid endarterectomy. Conclusion : The stroke and death rate in this study was among the lowest in CAS trials. The results indicate that the flow reversal system is safe and effective when used for neuroprotection during CAS and that it provides benefits in a broad patient population. © 2010 Wiley‐Liss, Inc.     

Carotid artery stenting in high surgical risk patients using the FiberNet® embolic protection system: The EPIC trial results

Objective: The multicenter EPIC (FiberNet Embolic Protection System in Carotid Artery Stenting Trial) single‐arm trial evaluated the 30‐day outcomes of a new design concept for embolic protection during carotid artery stenting (CAS). Background: Embolic protection filters available for use during CAS include fixed and over‐the‐wire systems that rely on embolic material capture within a “basket” structure. The FiberNet® Embolic Protection System (EPS), which features a very low crossing profile, consists of a three‐dimensional fiber‐based filter distally mounted on a 0.014 inch guidewire with integrated aspiration during filter retrieval. Methods: The trial enrolled 237 patients from 26 centers. Demographics, clinical and lesion characteristics, as well as adverse events through a 30‐day follow‐up were recorded. The mean age of the patients was 74 years, 64% were male and 20% had symptomatic carotid artery disease. Results: The combined major adverse event (MAE) rate at 30 days for all death, stroke, and myocardial infarction was 3.0%. There were three major strokes (two ischemic and one hemorrhagic) and two minor strokes (both ischemic) for a 2.1% 30‐day stroke rate. The procedural technical success rate was 97.5% and macroscopic evidence of debris was reported in 90.9% of the procedures. Conclusions: The FiberNet EPS, used with commercially available stents, produced low stroke rates following CAS in high surgical risk patients presenting with carotid artery disease. The unique filter design including aspiration during retrieval may have contributed to the low 30‐day stroke rate reported during CAS in patients considered at high risk for complications following carotid endarterectomy (CEA). © 2009 Wiley‐Liss, Inc.     

Carotid artery stenting with distal filter protection: single-center experience in high-surgical-risk patients

Carotid artery stenting (CAS) is an efficient alternative procedure for the treatment of high-surgical-risk patients with symptomatic and asymptomatic carotid stenosis. The use of cerebral protection systems might decrease procedural risk of stroke and death. We report our initial experience with protected carotid stenting in high-risk patients with severe carotid artery disease. From January 2006 until July 2008 we routinely performed CAS using a distal filter protection device in 65 consecutive high-surgical-risk patients with 72 high-grade carotid stenoses. Technical success rate was 97.2%. Neurologic periprocedural complications included two transient ischemic attacks and one major stroke. Three filter-related complications were managed without negative results to the patients. The overall in-hospital and 30-days MACE rate was 1.5%, 3.6% in symptomatic patients and 0% in asymptomatic patients. In our series of high-risk patients, CAS with the use of a distal filter protection system was safe and effective with a low incidence of periprocedural complications.     

The carotid artery revascularization and endarterectomy (CARE) registry: Objectives,design, and implications

This is the first comprehensive national registry that will provide data characterizing contemporary results of carotid endarterectomy (CEA) and carotid artery stenting (CAS). Carotid endarterectomy (CEA) has become the standard revascularization therapy to prevent stroke in patients with carotid artery disease, while carotid artery stenting (CAS) offers a percutaneous alternative in selected patients. Given the rapid growth in the numbers of CAS procedures being performed, there is a critical need for a national program to assess quality outcomes. The Carotid Artery Revascularization and Endarterectomy (CARE) Registry was developed through a multispecialty collaboration resulting in a comprehensive data collection tool for carotid revascularization procedures. The intent of the CARE registry is to collect and analyze clinical data to measure clinical practice, patient outcomes, and enable quality improvement for carotid revascularization. Finally, the CARE Registry satisfies the Center for Medicare and Medicaid Services (CMS) data reporting criteria for reimbursement. © 2008 Wiley‐Liss, Inc.     

SCAI/SVM expert consensus statement on Carotid Stenting: Training and credentialing for Carotid Stenting

Carotid artery stenting (CAS) has become an integral part of the therapeutic armamentarium offered by cardiovascular medicine programs for the prevention of stroke. The purpose of this expert consensus statement is to provide physician training and credentialing guidance to facilitate the safe and effective incorporation of CAS into clinical practice within these programs. Since publication of the 2005 Clinical Competence Statement on Carotid Stenting, there has been substantial device innovation, publication of numerous clinical trials and observational studies, accumulation of extensive real‐world clinical experience and widespread participation in robust national quality improvement initiatives [5]. Collectively, these advances have led to substantial evolution in the selection of appropriate patients, as well as in the cognitive, technical and clinical skills required to perform safe and effective CAS. Herein, we summarize published guidelines, describe training pathways, outline elements of competency, offer strategies for tracking outcomes, specify facility, equipment and personnel requirements, and propose criteria for maintenance of CAS competency. © 2015 Wiley Periodicals, Inc.     

Carotid Revascularization: A Systematic Review of the Evidence

Objective and Background

The aim of this study is to provide an evidence‐based review of the periprocedural safety and long‐term effectiveness of carotid artery stenting (CAS) compared to carotid endarterectomy (CEA), with particular attention paid to the use of embolic protection devices and patients at high risk for CEA.

Methods

Electronic databases (Ovid Medline, Cochrane central register of controlled trials, Pubmed, and Embase) were searched to identify: (1) randomized controlled trials (RCT) comparing outcomes of CEA and CAS, and (2) prospective clinical trials assessing the safety of CAS in patients at high surgical risk. Pooled incidence rates and one‐sided 95% confidence interval for the periprocedural and long‐term composite end‐point of stroke, myocardial infarction, or death among high surgical risk patients were generated and compared to objective performance criteria (OPC) reported by previous trials.

Results

Six RCTs and 14 prospective clinical trials met our search criteria. Selected RCTs showed inconsistency in reported periprocedural and long‐term outcome rates. Pooled incidence rates of the periprocedural and long‐term composite end‐point of stroke, myocardial infarction or death in high surgical risk candidates were 5.59% and 7.92%, respectively. These results were noninferior to selected OPCs (P‐value <0.001).

Conclusions

CAS represents a safe and effective stroke prevention strategy in high surgical risk patients when compared with CEA. The inconsistent results from the RCTs and the improved outcomes in the prospective clinical trials are likely related to variability in operator experience, use of embolic protection devices, and patient selection strategies.

     

Mid‐term outcomes of carotid artery stenting in patients with angiographic string sign

Objectives : To report on early and mid‐term outcomes of carotid artery stenting (CAS) in patients with angiographic string sign (SS). Background : Little is known about the prognosis of patients with carotid SS treated by CAS. Methods : We retrospectively evaluated early and mid‐term outcomes, together with ultrasound findings, in patients with SS treated by CAS at our institution. Results : Of 308 CAS procedures, SS was diagnosed in 6.2% (19 patients, 58% symptomatic). Carotid stent implantation was successful in 18 patients (success rate 95%). There were no peri‐procedural adverse events. One patient suffered from a transient ischemic attack during hospitalization and died of pneumonia. All remaining patients completed a 30‐day follow‐up, and no complications were reported (asymptomatic restenosis was diagnosed in 1 patient and successfully redilated). Six patients died of causes unrelated to CAS (pneumonia, decompensated heart failure, and contralateral stroke) before completing a 6‐month follow‐up. However, these patients presented with more pronounced, unfavorable clinical and angiographic characteristics compared to the rest of the patients. Conclusions : We suggest that CAS might be performed with acceptable procedural risk in patients presenting with SS, which is unsuitable for surgery. However, patients' clinical and angiographic characteristics must be carefully evaluated when considering interventional therapy, regardless of the favorable procedural outcomes. © 2011 Wiley Periodicals, Inc.     

Predicting Hemodynamic Changes of Cerebral Blood Flow during Temporal Carotid Occlusion: A Review of Current Knowledge with Implication for Carotid Artery Stenting

Carotid artery disease (CAD) plays an important role in the stroke development and its prevalence increases with aging of the population. Its wide variability of clinical manifestation ranges from incidental asymptomatic finding to devastating or fatal stroke, although cerebral collateral circulation is considered one of the major modifying factors. Over time, carotid artery stenting (CAS) has evolved into a reputable method for the treatment of patients with severe CAD. With expanding use of proximal protection systems resembling surgical clamp, there is an increasing demand to understand collateral cerebral circulation to protect patients from periprocedural hypoperfusion, which increases the risk of cerebral events. Transcranial Doppler ultrasound (TCD) is a useful tool allowing monitoring in real time during procedure patien$\acute{t}$s cerebral hemodynamic status providing the operator with valuable information. Its role in predicting periprocedural hypoperfusion is, however, less well established. In this article, we discuss the role of cerebral collateral circulation, summarize the current knowledge regarding its evaluation with TCD and suggest future implications for CAS.     

A "mouse in a trap" method for cerebral protection during carotid stenting: Technical note.

Carotid artery angioplasty and stenting (CAS) is now used as an alternative to surgical endarterectomy. The introduction of cerebral protection systems during stenting has improved carotid artery stenosis treatment, with less periprocedural complications. A "mouse in a trap" method was conceived and used in three patients. This involved an emboli entrapment-aspiration system using one proximal occluder in the common carotid artery and two distal occluders in the internal carotid artery or external carotid artery, followed by serial inflation-deflation cycles during each carotid stenting procedure. Debris was retrieved before dilation in one patient, after deployment in one, and after dilation in two. Although only used in a few cases to date, the method may improve the practice of CAS in treating patients with carotid stenosis, resulting in less thromboembolic events.     

The CAPTURE registry: results of carotid stenting with embolic protection in the post approval setting.

BACKGROUND: Pivotal study data examining carotid stenting with embolic protection as a less invasive alternative to endarterectomy for high surgical risk patients have been acquired under controlled conditions with highly selected physicians and hospitals. This report examines outcomes of carotid stenting post-approval after diffusion of this technology to a broader cross-section of physicians and hospitals. METHODS: The Carotid Acculink/Accunet Post-Approval Trial to Uncover Unanticipated or Rare Events (CAPTURE) is a prospective, multi-center registry to assess two important aspects of the post-IDE experience: the safety of carotid stenting by physicians with varying levels of experience as a measure of the adequacy of physician training, and the identification of rare/unexpected device-related complications. The primary endpoint was a composite of death, any stroke, or myocardial infarction within 30 days post-procedure. RESULTS: 3,500 patients were enrolled by 353 physicians at 144 sites. The 30-day primary endpoint event rate was 6.3% (95% CI: 5.5-7.1%) and did not differ among the three operator experience levels (5.3%, 6.0%, and 7.4%; P = 0.31) from most to least experienced, respectively. There were no differences in outcomes among physician specialties when adjusted for case mix. There were no unanticipated device related adverse events. CONCLUSIONS: The results of the CAPTURE study compare favorably to those achieved in the predicate pivotal investigations, and suggest that the post-approval transfer of this new therapy to the community practice setting via carotid stent training programs is effective in preparing physicians with varying experience levels and specialty training backgrounds.     

Multidisciplinary approach to carotid stenting

Background: Stroke neurologists, vascular surgeons, interventional neuroradiologists and interventional cardiologists have embraced carotid angioplasty and stenting (CAS) because of potential advantages over carotid endarterectomy (CEA). At Austin Health, a multidisciplinary neuro‐interventional group was formed to standardise indications and facilitate training. The aims of this study were to describe our organisational model and to determine whether 30‐day complications and early outcomes were similar to those of major trials. Methods: A clinical protocol was developed to ensure optimal management. CAS was performed on patients with high medical risk for CEA, with technically difficult anatomy for CEA, or who were randomised to CAS in a trial. Results: From October 2003 to May 2008, 47 patients (34 male, mean age 71.5) underwent CAS of 50 carotid arteries. Forty‐three cases had ipsilateral carotid territory symptoms within the previous 12 months. The main indications for CAS were high risk for CEA (n= 17) and randomised to CAS (n= 21). Interventionists were proctored in 27 cases. The procedural success rate was 94% with two cases abandoned because of anatomical problems and one because of on‐table angina. Hypotension requiring vasopressor therapy occurred in 12 cases (24%). The duration of follow up was one to 44 months (mean 6.8 months). The 30‐day rate of peri‐procedural stroke or death was 6% and the one‐year rate of peri‐procedural stroke or death or subsequent ipsilateral stroke was 10.6%. Restenosis occurred in 13% (all asymptomatic). Conclusion: A multidisciplinary approach is a useful strategy for initiating and sustaining a CAS programme.     

颈动脉狭窄患者的脑功能储备评价

颈动脉支架置入术（CAS）和颈动脉内膜切除术（QEA）是目前颈动脉狭窄患者最主要的非药物治疗方法。评价颈动脉狭窄患者的脑功能储备,不仅能筛选出近期可能面临卒中的高危患者,而且还能对无症状颈动脉狭窄患者行CEA和CAS的纳入标准进行修正,从而为患者提供最佳的治疗方案。文章对颈动脉狭窄患者的脑功能储备评价和MRI在其中的应用做了综述。     

Interventional Management of Asymptomatic Extracranial Carotid Stenosis

Carotid artery stenosis is a major risk factor for stroke and transient ischemic attack. Although carotid endarterectomy is the established gold standard for carotid revascularization, carotid artery angioplasty and stenting (CAS)—proven by large randomized clinical trials and rigorous registries and supported by improving stent designs, embolic protection, and increasing neurointerventionalist experience—is developing into a safer and more efficacious method of stroke prevention. Today, protected CAS is approved for symptomatic and asymptomatic patients with severe carotid stenosis with high surgical risk. We reviewed recently published data regarding new developments in the use of protected CAS, particularly in patients with carotid stenosis who are either asymptomatic or at low surgical risk.     

Utilization of Intravascular Ultrasound during Carotid Artery Stenting

For patients at high risk for surgery, carotid artery stenting (CAS) is a viable alternative to help reduce risk of stroke for patients with high-grade carotid artery stenosis; however, a higher incidence of perioperative stroke has been observed in patients undergoing stenting compared to those undergoing open surgery. Intravascular ultrasound (IVUS) is commonly used during coronary artery procedures to help evaluate lesions and to guide stent placement. Multiple groups have sought to determine whether IVUS could also be used during CAS. While IVUS has been shown to be both feasible and safe during CAS, there is limited evidence that demonstrates direct improvement in procedural outcomes. Further studies focusing on clinical outcomes should be conducted in order to justify routine use of this technology during CAS.     

The CAPTURE registry: predictors of outcomes in carotid artery stenting with embolic protection for high surgical risk patients in the early post-approval setting.

BACKGROUND: The use of carotid artery stenting with embolic protection has been practiced for over a decade in the United States, and increasingly so since carotid stenting received FDA approval in 2004. While there have been attempts at establishing predictors of outcomes in carotid artery stenting, they have generally been limited to single center experiences and/or multicenter retrospective surveys. This report examines predictors of outcomes in carotid stenting in the earliest and largest prospective multicenter neurologist-adjudicated experience in the United States post device approval. METHODS: The Carotid Acculink/Accunet Post-Approval Trial to Uncover Unanticipated or Rare Events (CAPTURE) is a prospective, multi-center registry conducted to assess outcomes of carotid artery stenting (CAS) in the noninvestigational setting following device approval for high surgical risk patients (symptomatic with > or =50% stenosis; asymptomatic > or =80% stenosis). A neurologist examined the patients before the procedure, at 24 hr and 30-days post-procedure. The primary endpoint was a composite of death, any stroke, or myocardial infarction within 30-days post-procedure. Strokes and neurological events suspected to be strokes were adjudicated by an independent Clinical Events Adjudication Committee (CEAC) using prespecified definitions. Logistic regression analysis was performed to determine clinical, procedural, and anatomic predictors of endpoint outcomes. RESULTS: Three thousand five hundred patients were enrolled at 144 sites by 353 physicians of varying specialty backgrounds and CAS experience. The 30-day primary endpoint event rate of death, stroke and MI was 6.3% [95% CI: 5.5-7.1%], and the rate of major stroke and death 2.9% [95% CI: 2.4-3.5]. Predictors of adverse outcomes included age, symptomatic patients, predilation prior to embolic protection device placement, time from symptoms to CAS procedure, and the use of multiple stents. CONCLUSIONS: In general, carotid stenting is performed safely in patients with severe stenosis at high surgical risk, with best outcomes in younger asymptomatic patients. However, there are certain patient and procedural characteristics that are associated with poorer outcomes. In these patients, the risk of stenting should be considered vis-à-vis both the anticipated benefit as well as the alternative surgical and medical options.     

Starting a carotid artery stenting program is safe

Background : Little is known on the performance of newly initiated carotid artery stenting (CAS) programs. The safety of the procedure is being questioned following the publication of the EVA‐3S trial, a study criticized for the limited interventional experience required to enroll patients. Methods : Within a newly started academic CAS program, patient data and outcomes were collected prospectively. The outcomes of the first 100 consecutive patients treated are reported. A CAS‐fellowship‐trained interventionalist was involved in all procedures. All patients underwent clinical assessment by a neurologist before and after the procedure, and serial ECG and cardiac enzymes were routinely obtained. Primary outcome measures included 30‐day major adverse events (MAE), defined as death, stroke, or myocardial infarction, while on follow‐up deaths and ipsilateral strokes were added. Results : Between July 2003 and November 2006, 92 patients had a single internal carotid artery treated, while 7 underwent staged bilateral CAS. In one patient, the procedure was aborted prior to lesion treatment. The 30‐day MAE rate per procedure was 1.9% (one major and one minor stroke). By a mean follow‐up of 16 months (range 2–42 months), one patient had died of refractory heart failure, while one patient had a minor ipsilateral stroke and three had minor contralateral strokes, corresponding to total MAE per patient of 4%. The rate of any stroke or death was 7%. The rate of restenosis ≥50% per lesion by ultrasound was 3.8%. Conclusion : This single center experience suggests that it is safe to start a CAS program following dedicated fellowship. © 2008 Wiley‐Liss, Inc.     

Symptomatic carotid artery stenosis: what is the preferred treatment?

Stroke is a major cause of mortality, morbidity, and disability. Carotid artery disease is the etiology for 15% to 20% of stroke. Carotid endarterectomy (CEA) reduces the risk of ipsilateral stroke and death in symptomatic patients with 50% to 99% carotid artery stenosis when the operative risk of stroke or death is less than 6%. Treatment benefit is greater with earlier surgery, more severe stenoses, and older age. Recently, carotid artery stenting (CAS) has emerged as a treatment option, especially in patients with high surgical risk due to anatomic or clinical variables. Nondisabling stroke risk may be higher with CAS than CEA, but the difference is narrowed with the use of embolic protection devices. The risk for myocardial infarction is lower with CAS than CEA. There is no difference in risk for disabling stroke or death. Worse results with new or low-volume CAS operators is a concern. CEA and CAS are complementary revascularization strategies. CEA may be preferred in older patients with complex anatomy or bulky plaques. CAS may be preferred in younger patients and those with restenosis, history of neck radiation, surgical contraindications, or surgically inaccessible lesions. The role for optimal medical therapy as an alternative treatment strategy remains to be defined. Nevertheless, all patients should be treated with lifestyle interventions and secondary risk factor control to target levels to reduce the risk of subsequent atherosclerotic events.