Carotid Artery Stenting

Learning curve of transfemoral carotid artery stenting in the vascular quality initiative registry

OBJECTIVE

With the recent expansion of the Centers for Medicare and Medicaid Services coverage, transfemoral carotid artery stenting (tfCAS) is expected to play a larger role in the management of carotid disease. Existing research on the tfCAS learning curve, primarily conducted over a decade ago, may not adequately describe the current effect of physician experience on outcomes. Because approximately 30% of perioperative strokes/deaths post-CAS occur after discharge, appropriate thresholds for in-hospital event rates have been suggested to be <4% for symptomatic and <2% for asymptomatic patients. This study evaluates the tfCAS learning curve using Vascular Quality Initiative (VQI) data.

METHODS

We identified VQI patients who underwent tfCAS between 2005 and 2023. Each physician's procedures were chronologically grouped into 12 categories, from procedure counts 1-25 to 351+. The primary outcome was in-hospital stroke/death rate; secondary outcomes were in-hospital stroke/death/myocardial infarction (MI), 30-day mortality, in-hospital stroke/transient ischemic attack (stroke/TIA), and access site complications. The relationship between outcomes and procedure counts was analyzed using the Cochran-Armitage test and a generalized linear model with restricted cubic splines. Our results were then validated using a generalized estimating equations model to account for the variability between physicians.

RESULTS

We analyzed 43,147 procedures by 2476 physicians. In symptomatic patients, there was a decrease in rates of in-hospital stroke/death (procedure counts 1-25 to 351+: 5.2%-1.7%), in-hospital stroke/death/MI (5.8%-1.7%), 30-day mortality (4.6%-2.8%), in-hospital stroke/TIA (5.0%-1.1%), and access site complications (4.1%-1.1%) as physician experience increased (all P values < .05). The in-hospital stroke/death rate remained above 4% until 235 procedures. Similarly, in asymptomatic patients, there was a decrease in rates of in-hospital stroke/death (2.1%-1.6%), in-hospital stroke/death/MI (2.6%-1.6%), 30-day mortality (1.7%-0.4%), and in-hospital stroke/TIA (2.8%-1.6%) with increasing physician experience (all P values <.05). The in-hospital stroke/death rate remained above 2% until 13 procedures.

CONCLUSIONS

In-hospital stroke/death and 30-day mortality rates after tfCAS decreased with increasing physician experience, showing a lengthy learning curve consistent with previous reports. Given that physicians' early cases may not be included in the VQI, the learning curve was likely underestimated. Nevertheless, a substantially high rate of in-hospital stroke/death was found in physicians' first 25 procedures. With the recent Centers for Medicare and Medicaid Services coverage expansion for tfCAS, a significant number of physicians would enter the early stage of the learning curve, potentially leading to increased postoperative complications.

Impact of Physician Experience on Stroke or Death Rates in Transfemoral Carotid Artery Stenting: Insights from the Vascular Quality Initiative

Objective

With the recent expansion of the Centers for Medicare and Medicaid Services (CMS) coverage, transfemoral carotid artery stenting (tfCAS) is expected to play a larger role in the management of carotid disease. Existing research on the tfCAS learning curve, primarily conducted over a decade ago, may not adequately describe the current effect of physician experience on outcomes. This study evaluates the tfCAS learning curve using VQI data.

Methods

We analyzed tfCAS patient data from 2005-2023. Each physician's procedures were chronologically grouped into 12 categories, from procedure counts 1-25 to 351+. Primary outcome was in-hospital stroke/death rate; secondary outcomes were in-hospital stroke/death/MI, 30-day mortality, and in-hospital stroke/TIA. The relationship between outcomes and procedure counts was analyzed using Cochran Armitage test and a generalized linear model with restricted cubic splines, validated using generalized estimating equations.

Results

We analyzed 43,147 procedures by 2,476 physicians. In symptomatic patients, there was a decrease in rates of in-hospital stroke/death (procedure counts 1-25 to 351+: 5.2% to 1.7%), in-hospital stroke/death/MI (5.8% to 1.7%), 30-day mortality (4.6% to 2.8%), in-hospital stroke/TIA (5.0% to 1.1%) (all p-values<0.05). The in-hospital stroke/death rate remained above 4% until 235 procedures. Similarly, in asymptomatic patients, there was a decrease in rates of in-hospital stroke/death (2.1% to 1.6%), in-hospital stroke/death/MI (2.6% to 1.6%), 30-day mortality (1.7% to 0.4%), and in-hospital stroke/TIA (2.8% to 1.6%) with increasing physician experience (all p-values<0.05). The in-hospital stroke/death rate remained above 2% until 13 procedures.

Conclusions

In-hospital stroke/death and 30-day mortality rates post-tfCAS decreased with increasing physician experience, showing a lengthy learning curve consistent with previous reports. Given that physicians' early cases may not be included in the VQI, the learning curve was likely underestimated. With the recent CMS coverage expansion for tfCAS, a significant number of physicians would enter the early stage of the learning curve, potentially leading to increased post-operative complications.

Proximal balloon-guided catheter with flow inversion vs. distal filter protection during the carotid stent placement, a seven years experience in a Colombian reference center

BACKGROUND AND PURPOSE

The carotid stent placement as a therapeutic option for carotid stenosis has been increasing among years; therefore, studies are required to evaluate the security and efficacy of its materials. The purpose of this study was to evaluate the distal filter and the proximal balloon-guided catheter with flow inversion as protection devices during carotid angioplasty and stenting.

METHODS

This is a retrospective, observational study of patients diagnosed with carotid stenosis treated with angioplasty between January 1, 2014, and June 30, 2020; we analyzed a radiology service database to compare the distal filter and the proximal balloon-guided catheter as protection devices during angioplasty.

RESULTS

One hundred seventy-five angioplasties were performed, the distal filter was the most prevalent embolic protection device used (66%), patients baseline characteristics did not differ between groups with different embolic protection devices, except for history of dyslipidemia (p < 0.000). As well, we did not find any significant differences between the groups in the device related complications, intervention time (p = 0.140), unrelated complications (p = 0.693) and functional independence at 90 days (p = 0.096).

CONCLUSIONS

In our study the proximal balloon-guided catheter and the distal filter protection device as protection devices during the carotid stenting didn't show significant differences regarding complications related to the system.

Early and Long-Term Outcomes of Carotid Stenting and Carotid Endarterectomy in Women

Background: The role of carotid revascularization in women remains intensely debated because of the lower benefit and higher perioperative risks concerning the male counterpart. Carotid artery endarterectomy (CEA) and stenting (CAS) represent the two most valuable stroke prevention techniques due to large vessel disease. This study investigates the early and late outcomes in female sex in a real-world everyday clinical practice.

Methods: Data were retrospectively analyzed from a single-center database prospectively compiled. A total of 234 procedures, both symptomatic and asymptomatic, were identified (98 CEAs and 136 CASs). Perioperative risks of death, cerebral ischemic events, and local complications were analyzed and compared between the two groups. Long-term outcomes were evaluated in overall survival, freedom from ipsilateral stroke/transient ischemic attack, and freedom from restenosis (>50%) and reintervention.

Results: Women who underwent CAS and CEA did not differ in perioperative ischemic cerebral events (2.2 vs. 0%, p = 0.26) and death (0.8 vs. 0%, p = 1). Other perioperative and 30-day outcomes were similarly distributed within the two groups. Kaplan–Meier curves between CAS and CEA groups highlighted no statistical differences at 6 years in overall survival (77.4 vs. 77.1%, p = 0.47) of ipsilateral stroke/transient ischemic attack (94.1 vs. 92.9%, p = 0.9). Conversely, significant differences were showed in 6 years freedom from restenosis (93.1 vs. 83.3%, p = 0.03) and reinterventions (97.7 vs. 87.8%, p = 0.015).

Conclusion: Our results revealed that both CEA and CAS have acceptable perioperative risk in women. Long-term outcomes highlighted favorable indications for both procedures, especially for CAS, which seemed to be an excellent alternative to CEA in female patients when performed by well-trained operators.

Personalized-medicine on carotid endarterectomy and stenting

Evidence based medicine (EBM) is the core of current clinical guidelines and is considered as the gold standard of clinical practice. Despite this, a number of limitations and criticisms are moved to EBM. The major one is that this method privileges randomized controlled trials (RCTs), in which the selection of patients is often based on rigid inclusion criteria. The lack of “pragmatism” of some RCTs sometimes makes it difficult to apply guidelines that derive from them to patients observed in clinical practice, who are often affected by comorbidities and disabilities. The new paradigm to overcome this limitation is personalized medicine (PM), which aims to take into account the particular characteristics displayed by the individual. In order to tailor the best treatment for the patient, PM uses EBM but emphasizes the person's specific information from the assessment of the clinic, lifestyle and risk/benefit scores. This narrative review tries to find the best evidence by analysing subgroups and risk scores of patients from meta-analysis and RCTs in order to try to apply PM and to provide good practice points (GPP) on grey aspects and open questions not fully covered by current guidelines on carotid endarterectomy (CEA) and stenting for stroke prevention.

Multivariable Analysis of Patients With Severe Persistent Postprocedural Hypotension After Carotid Artery Stenting

Purpose: To assess the incidence and predictors of severe, persistent postprocedural hypotension (PPH) after carotid artery stenting (CAS). Materials and Methods: A total of 146 patients (mean age 72.8 years; 104 men) who underwent 160 CAS procedures using a standardized protocol at 3 vascular centers were retrospectively analyzed. The primary endpoint was postprocedural hypotension, defined as a reduction in systolic blood pressure (SBP) >40 mm Hg from baseline or an SBP of <90 mm Hg sustained for >1 hour after CAS. Potential prognostic factors for postprocedural hypotension were identified and subjected to logistic regression analyses; outcomes are presented as the odds ratios (ORs) with 95% confidence intervals (CIs). Results: PPH developed in 36 (24.7%) patients after 37 (23.1%) CAS procedures. These patients had significantly longer intensive care unit and hospital stays than those who did not develop hypotension (p<0.001). PPH was associated with severe lesion calcification (OR 6.28, 95% CI 1.81 to 21.98, p=0.004) and contrast volume (OR 1.02, 95% CI 1.01 to 1.02, p<0.001). A 4-fold increase in the risk of PPH (OR 4.22, 95% CI 1.38 to 13.33, p=0.012) was found between the embolic protection device most associated with PPH (Angioguard) and the device least associated with PPH (Emboshield NAV6). A similar trend was also observed for the Precise vs Xact stents (OR 6, 95% CI 2.08 to 17.6, p=0.001). Bootstrapped multivariable modeling identified the Precise stent and contrast volume as significant predictors of persistent postprocedural hypotension. Further investigation of the contrast volume revealed associations with sex, severe calcification, arch type, previous coronary artery bypass surgery, and primary stenting, suggesting that the contrast volume reflects the complexity of the procedure. Conclusion: The complexity of the procedure and type of stent may play a role in the development of postprocedural hypotension after CAS.

Thirty-day results from prospective multi-specialty evaluation of carotid artery stenting using the CGuard MicroNet-covered Embolic Prevention System in real-world multicentre clinical practice: the IRON-Guard study

AIMS

The aim of the present study was to evaluate periprocedural and 30-day outcomes in a prospective series of patients treated with the CGuard Embolic Prevention System (EPS).

METHODS AND RESULTS

From April 2015 to June 2016, a physician-initiated prospective multicentre study was performed in 200 consecutive patients admitted for protected carotid artery stenting (CAS) and treated using the CGuard EPS in twelve vascular centres. Outcome measures were: technical success, periprocedural (0-24 hours) and post-procedural (24 hours-30 days) major and minor strokes, death, acute myocardial infarction (AMI), transient ischaemic attack (TIA), and external carotid occlusion. In three centres, consecutive diffusion-weighted magnetic resonance cerebral imaging (DW-MRI) was performed ≤72 hours prior to and within 72 hours after the intervention. A distal embolic protection device was employed in 182 patients (91%). Technical success was 100%. No death, AMI or major stroke occurred periprocedurally. There were two TIAs and five periprocedural minor strokes (2.5%), including one thrombosis solved by surgery. In the remaining patients (199/200; 99.5%) one-month follow-up duplex ultrasound revealed optimal technical results. Post-procedural clinical follow-up was uneventful. No external carotid artery occlusion occurred. New post-procedural DW-MRI lesions were detected in 12 patients out of 61 (19.6%), including bilateral in five (8.2%) and isolated ipsilateral in six (9.8%), whereas one patient (1.6%) had contralateral only lesions.

CONCLUSIONS

Multicentre multi-specialty use of the CGuard EPS in routine clinical practice was associated with no major periprocedural neurologic complications and a total elimination of post-procedural neurologic complications by 30 days.

An update of the Italian Stroke Organization–Stroke Prevention Awareness Diffusion Group guidelines on carotid endarterectomy and stenting: A personalized medicine approach

Although proof-based medicine has generated much valid evidence for the drawing up of guidelines and recommendations for best clinical practice in symptomatic and asymptomatic carotid stenosis, whether and when it is better to employ endarterectomy or stenting as the intervention of choice still remain matters of debate. Moreover, guidelines have been targeted up to now to the ‘representative’ patient, as resulting from the statistical analyses of the studies conducted on the safety and efficacy of both interventions as well as on medical therapy alone. The Italian Stroke Organization (ISO) and Stroke Prevention and Awareness Diffusion (SPREAD) group has thus decided to update its statements for an 8th edition. To this end, a multidisciplinary team of authors representing Italian scientific societies in the neurology, neuroradiology, vascular and endovascular surgery, interventional cardiology, and general medicine fields re-examined the literature available on stroke. Analyses and considerations on patient subgroups have allowed to model the risks/benefits of endarterectomy and stenting in the individual. Accordingly, the guideline's original methodology has been revised to follow the new SIGN (Scottish Intercollegiate Guideline Network) Grade-like approach, integrating it with new considerations on Precision, or Personalized Medicine. Therefore, this guideline offers recommendations on precision medicine for the single patient, and can be followed in addition to the more standard guidelines.

Management of asymptomatic carotid stenosis

With modern intensive medical therapy, the risk of ipsilateral stroke in patients with asymptomatic carotid stenosis (ACS) is below the risk of either carotid stenting or endarterectomy. Routine intervention for ACS is therefore not justified; approximately 90% of patients with ACS would be better off with intensive medical therapy. The few who could benefit can be identified by transcranial Doppler embolus detection or features of vulnerable plaque that can be imaged by 3-dimensional ultrasound, MRI or positron emission tomography/computed tomography; some of these methods are still in development.

Recommendations for carotid stenting in Korea

Carotid artery angioplasty with stenting (CAS) is being performed in many hospitals in Korea. Most of the guidelines which are being used are similar, but the practical aspects such as techniques are different between hospitals. For example, usage of various protective devices, the oral antiplatelet regimen prior to procedure and placing of temporary pacemaker to prevent bradycardia are different between hospitals. In this article, we summarize and propose the guidelines for CAS which is currently being accepted in Korea. These guidelines may be helpful in providing protocol to neurointerventionalist who perform CAS and to standardize the process including reporting of CAS in the future comparative trials in Korea.

An Update on Italian Stroke Organization Guidelines on Carotid Endarterectomy and Stenting

One hundred and fifty-three authors, 45 Italian scientific societies, and two Italian patients' associations participated in drafting the Italian Stroke Organization document, which has become the national guideline for the prevention and treatment of stroke in Italy. For the surgical therapy section of the Italian Stroke Organization document, the main trials on carotid endoarterectomy and stenting were critically reviewed in order to formulate recommendations for these procedures. Recommendations are presented here for the referral of patients to either carotid endarterectomy or stenting on the basis of whether carotid stenosis is symptomatic or asymptomatic.

Cerebral microemboli and neurocognitive change after carotid artery stenting with different embolic protection devices

OBJECTIVES

Proximal cerebral protection devices have been developed as an alternative to filter protection devices for reducing neurological complications during carotid artery stenting (CAS). The aim of the present study was to evaluate the frequency of silent cerebral embolism after CAS using different cerebral embolic protection devices and the impact of silent cerebral embolism on neurocognitive function.

METHODS

One hundred consecutive patients who underwent CAS were enrolled. The patients were randomized to either proximal balloon occlusion or filter protection. Neurocognitive tests were performed before and six months after CAS. Cerebral embolisms were evaluated with diffusion-weighted magnetic resonance imaging (DW-MRI).

RESULTS

The number and volume of new ischemic lesions found with DW-MRI were higher in the filter protection group than in the proximal balloon occlusion group. According to our definition, nine (21%) patients in the balloon occlusion group and 16 (36%) patients in the filter protection group showed neurocognitive decline, and ten (23%) patients in the balloon occlusion group and four (9%) patients in the filter protection group showed neurocognitive improvement (NS). Regarding the group of patients with new cerebral ischemic lesions on DW-MRI, neurocognitive decline occurred in 14 (31%) of 45 patients with DW-MRI lesions and 11 (26%) of 43 patients without DW-MRI lesions (NS).

CONCLUSION

Neurocognitive outcome after CAS is unpredictable; both neurocognitive decline and improvement can occur. In this study, the proximal balloon occlusion system significantly decreased cerebral microemboli during CAS compared to filter protection. Cerebral microembolism was not found to be associated with neurocognitive decline.

[Current guidelines on carotid artery stenting. Critical evaluation]

Scientific data underlying current guidelines on treatment of carotid artery stenosis is subject to interdisciplinary discussion. In particular selective weighting of the randomized European studies leads to conflicting levels of recommendation and levels of evidence, especially when directly comparing guidelines under surgical versus endovascular guidance. Surgical guidelines recommend a limitation of carotid artery stenting (CAS) to symptomatic patients with specific surgical/anatomical disadvantages and/or severe comorbidities. The European Society of Cardiology (ESC) guidelines recommend the use of CAS only in patients at increased surgical risk but at the same time requires morbidity and mortality rates comparable to those of surgical interventions. Even one step further, the American guidelines and specifically the associated comments of the German Society of Cardiology on the above mentioned ESC guidelines put CAS and carotid endarterectomy (CEA) on a par in terms of treatment alternatives, presupposing analogous CEA complication rates. Differential interpretation of the so far inadequate data is a common issue of current evidence-based medicine. The difficulty in conceptualization of new studies concerning the therapy of carotid stenosis lies in the funding these large projects and also on the high patient number required to achieve adequate statistical power. Furthermore, during the estimated long study period substantial changes of current techniques and devices can be anticipated which might render the study results in part outdated by the time of publication. However, as long as no new randomized study results comparing medical, surgical and interventional treatment of carotid stenosis are available, the question on the optimal therapy for patients with carotid artery disease remains unanswered.

Acceleration time ratio for the assessment of extracranial internal carotid artery stenosis

PURPOSE

To apply the acceleration time (AcT) ratio as an additional marker for diagnosing internal carotid artery (ICA) stenosis.

METHODS

Carotid artery sonography was performed in 140 patients, and the AcT ratio was calculated as the AcT of the ICA divided by the AcT of the ipsilateral common carotid artery, and compared with diameter stenosis.

RESULTS

There was a significant correlation between diameter stenosis and the AcT ratio. The receiver operating characteristic curve revealed a cutoff level of 1.5, with 90.0 % sensitivity and 93.5 % specificity for stenosis >65 %.

CONCLUSION

Our results indicate that applying the AcT ratio can help in the diagnosis of ICA stenosis.

Carotid Artery Stenting: Operator and Institutional Learning Curves

Despite rapid growth in the frequency that carotid artery stenting (CAS) is performed, there remain concerns regarding the steep learning curve associated with this procedure. This article reviews the evidence base supporting operator and institutional CAS learning curves and discusses their implications for the establishment and maintenance of competencies. Attempts are made to delineate minimum volume thresholds to attain these goals and means to enhance procedural safety without compromising patient access.

Usefulness of acceleration time for internal carotid artery origin stenosis

Calcification of the internal carotid artery (ICA) hinders accurate evaluation of the stenosis by conventional ultrasonography due to acoustic shadow. We examined the relationship between acceleration time (AcT) and ICA origin stenosis. One hundred thrity seven samples (266 vessels) that enforced duplex ultrasonography in our hospital were targeted. The results have shown that there is a significant relationship between AcT and stenosis. AcT of more than 110 msec suggests that the stenosis is more than 60% by the North American Symptomatic Carotid Endarterectomy Trial (NASCET) method. AcT is thought to be useful for the diagnosis of ICA stenosis with calcification. (English Translation of J Jpn Coll Angiol 2011; 51: 365-371).

Objective simulator-based evaluation of carotid artery stenting proficiency (from Assessment of Operator Performance by the Carotid Stenting Simulator Study [ASSESS])

Studies have suggested that operator proficiency has a substantial effect on complication rates and procedural outcomes. Endovascular simulators have been used for training and have been proposed as an alternative to the conventional assessment of skills. The present study sought to validate simulation as an objective method for proficiency evaluation in carotid artery stenting. Interventional cardiologists classified as novice, intermediate, or experienced practitioners performed 3 simulated, interactive carotid stenting cases on an AngioMentor endovascular simulator. An automated algorithm scored the participants according to the technical performance, medical management, and angiographic results. A total of 33 interventional cardiologists (8 novices, 15 intermediates, and 10 experts) completed 82 simulated procedures. The composite scores for the case simulations varied significantly by operator experience, with better scores for the more experienced groups (p <0.0001). The metrics that discriminated between operator experience groups included fluoroscopy time, crossing the carotid lesion with devices other than a 0.014-in. wire before filter deployment, and incomplete coverage of the lesion by the stent. In conclusion, the results of the present study validate that a simulator with an automated scoring system is able to discriminate between levels of operator proficiency for carotid artery stenting. Simulator-based performance assessment could have a role in initial and ongoing proficiency evaluations and credentialing of interventional operators of high-risk endovascular procedures.

Age and gender disparities in the risk of carotid revascularization procedures

The potential effect of age and gender stratification in the outcome of patients with carotid artery stenosis undergoing carotid revascularization procedures (CRP) may have important implications in clinical practice. Both European Stroke Organization and American Heart Association guidelines suggest that age and sex should be taken into account when selecting a CRP for an individual patient. We reviewed available literature data through Medline and Embase. Our search was based on the combination of terms: age, gender, sex, carotid artery stenosis, carotid artery stenting (CAS) and carotid endarterectomy (CEA). Postoperative stroke and mortality rates increased with age after any CRP (CEA or CAS), especially in patients aged over 75 years. Older patients with carotid artery stenosis undergoing CAS were found to have a nearly double risk of stroke or death compared with CEA, while CEA was found to benefit more patients aged over 70 years with symptomatic carotid artery stenosis. Male patients with symptomatic or asymptomatic carotid artery stenosis had lower stroke/mortality rates and benefited more from CEA compared with females. For the periprocedural risk of stroke or death in patients with carotid artery stenosis after CAS no sex differences were found. Therefore, CEA appears to have lower perioperative risks than CAS in patients aged over 70 years, and thus should be the treatment of choice if not contraindicated. The periprocedural risk of CEA is lower in men than in women, while there was no effect of gender on the periprocedural risk of CAS.

Effects of carotid artery stenting on cognitive function in patients with mild cognitive impairment and carotid stenosis

Carotid stenosis is known to be an independent risk factor in the transformation process of mild cognitive impairment (MCI) to dementia and is treated by carotid artery stenting (CAS); however, the effects of CAS on cognitive function are unclear. In this study, 240 patients were prospectively assigned to a CAS or control group according to patient preference and underwent detailed neuropsychological examinations (NPEs) before and 6 months after treatment. Cerebral perfusion was assessed with computed tomography perfusion (CTP). Among the 240 patients included in the study, 208 patients completed NPEs at baseline and 6 months after therapy. The patients in the two groups did not differ with regard to baseline characteristics, educational level, vascular risk factors (VRFs) and NPEs prior to therapy. Significant improvements in the Mini-Mental State Examination (MMSE; before, 24.6±1.7 vs. after, 24.8±1.9; P=0.016), Montreal Cognitive Assessment (MOCA; before, 23.7±1.7 vs. after, 24.1±2.0; P=0.006), Fuld Object Memory Evaluation (FOME; before, 13.8±2.2 vs. after, 14.0±2.3; P=0.031) and Wechsler Adult Intelligence Scale-digital span (WAIS-DS; before, 6.7±2.1 vs. after, 6.9±2.3; P=0.040) were observed in the CAS group; however, improvements were not observed in the control group. Of the 84 patients in the CAS group who received CTP follow-up, 72 (86%) presented improvements in ipsilateral brain perfusion 6 months after the procedure; however, no improvement was observed in the control group. Close correlations were identified between the change in perfusion and the change in MMSE (r=0.575) and MOCA (r=0.574). CAS improves global cognitive function in patients with carotid stenosis and MCI and the improvement of cognition is closely related to the improvement of cerebral perfusion.

Diagnosis of and treatment for symptomatic carotid stenosis: an updated review

Carotid stenoses of ≥50% account for about 15-20% of strokes. Their degree may be moderate (50-69%) or severe (70-99%). Current diagnostic methods include ultrasound, MR- or CT-angiography. Stenosis severity, irregular plaque surface, and presence of microembolic signals detected by transcranial Doppler predict the early recurrence risk, which may be as high as 20%. Initial therapy comprises antiplatelets and statins. Benefit of revascularization is greater in men, in older patients, and in severe stenosis; patients with moderate stenoses may also profit particularly if the plaque has an irregular aspect. An intervention should be performed within <2 weeks. In large randomized studies comparing endarterectomy and stenting, endovascular therapy was associated with a higher risk of periprocedural stroke, yet in some studies, with a lower risk of myocardial infarction and of cranial neuropathy. These trials support endarterectomy as the first choice treatment. Risk factors for each of the two therapies have been indentified: coronary artery disease, neck radiation, contralateral laryngeal nerve palsy for endarterectomy, and, elderly patients (>70 years), arch vessel tortuosity and plaques with low echogenicity on ultrasound for carotid stenting. Lastly, in direct comparisons, a contralateral occlusion increases the risk of periprocedural complications in both types of treatment.

Role of patient-specific virtual reality rehearsal in carotid artery stenting

Background

Recent advances in simulation science permit patient-specific rehearsal of endovascular stenting procedures. This study aimed to evaluate how effectively real interventions are replicated by patient-specific rehearsal technology, and to assess its value as a preparatory tool for the interventionalist and the operating team.

Methods

All patients deemed candidates for carotid artery stenting procedures with suitable computed tomography images were enrolled. Each team member rehearsed the virtual procedure in the laboratory, simulated operating theatre or angiography suite environment immediately before treating the real patient. Dexterity and qualitative metrics were recorded. Subjective questionnaires used a Likert scale from 1 (poor) to 5 (excellent).

Results

Of 18 patients, three were excluded. In 11 of 15 and 13 of 15 patients respectively endovascular tool use and fluoroscopy angles were identical during rehearsal and the real procedure. In a third of patients, the simulator did not adequately predict difficulties in cannulating the stenotic internal or common carotid arteries. The procedure realism, value in evaluating the case, increase in efficiency in tool use, and potential to increase communication, confidence and team performance were all rated highly (4 of 5).

Conclusion

Patient-specific rehearsal was rated highly for both face and content validity. Access strategy, endovascular material use and angiographic imaging were all replicated effectively, although certain biomechanical vessel properties seemed to be replicated to a lesser degree. Patient-specific rehearsal constitutes a unique tool that may help tailor endovascular material choice, and optimize the preoperative preparation of the interventionalist and team.

Outcomes After Carotid Artery Stenting and Endarterectomy in the Medicare Population

Background and Purpose—

Carotid artery stenting (CAS) is an alternative to carotid endarterectomy (CEA) for stroke prevention. The value of this therapy relative to CEA remains uncertain.

Methods—

In 10 958 Medicare patients aged 66 years or older between 2004 and 2006, we analyzed in-hospital, 1-year stroke, myocardial infarction, and death rate outcomes and the effects of potential confounding variables.

Results—

CAS patients (87% were asymptomatic) had a higher baseline risk profile, including having a higher percentage of coronary and peripheral arterial disease, heart failure, and renal failure. In-hospital stroke rate (1.9% CAS versus 1.4% CEA; P =0.14) and mortality (CAS 0.9% versus 0.6% CEA; P =0.20) were similar. By 1 year, CAS patients had similar stroke rates (5.3% CAS versus 4.1% CEA; P =0.12) but higher all-cause mortality rates (9.9% CAS versus 6.1% CEA; P <0.001). Using Cox multivariable models, there was a similar stroke risk (hazard ratio, 1.28; 95% CI, 0.90–1.79) but CAS patients had a significantly higher mortality (HR, 1.32; 95% CI, 1.02–1.71). Sensitivity analyses suggested that unmeasured confounders could be responsible for the mortality difference. In multivariable analysis, stroke risk was highest in the patients symptomatic at the time of revascularization.

Conclusions—

CAS patients had a similar stroke risk but an increased mortality rate at 1 year compared with CEA patients, possibly related to the higher baseline risk profile in the CAS patient group.

Classification for carotid artery stenting complications: manifestation, management, and prevention

Carotid artery stenting is a rapidly evolving method for treating carotid artery disease. Various intraprocedural and postprocedural complications have been reported in the literature. However, the absence of a unified classification scheme for these complications makes it difficult, if not impossible, to study their precise incidence, predictors, and management. The aim of this article is to propose the first joint classification of periprocedural complications, to analyze their incidence and etiology, and suggest possible ways to manage and prevent them. This classification is intended to be used as a common platform for prompt recognition, evaluation, treatment, and universal study of the complications during carotid stenting procedures. For this purpose, the opinions of the major experts on carotid interventions worldwide were merged with all the available information reported in the English-language literature to present as accurately as possible the management and prevention of carotid stenting complications according to this proposed classification.

Carotid artery stenting in octogenarians using a proximal endovascular occlusion cerebral protection device: a multicenter registry

BACKGROUND

Carotid stenting (CAS) has been proposed as an alternative to carotid endoarterectomy also in elderly patients with discrepant results. However, the use of proximal neuroprotection devices have not been evaluated in octogenarians.

PURPOSE

The aim of this multicenter prospective registry was to demonstrate that CAS in octogenarians is safe and effective if performed in high-volume centers by experienced operators.

METHODS

From July 2005 to May 2009, a total of 198 octogenarians patients, in three different institutions, were included in this registry. All patients underwent CAS using proximal endovascular occlusion device (Mo.Ma. device Invatec, Roncadelle, Italy). An independent neurologist evaluated all patients. The primary endpoint was death and stroke rate at 30 days.

RESULTS

198 octogenarians (135 men; mean age: 83.2 years) were included in the registry. 39.4% of the patients were symptomatic. Procedural success was 100%. In-hospital complications: Two minor and two major strokes (2.02%) occurred. No device-related complications and no serious access site complication were noted. Between discharge and 30-day follow-up, one patient died due to a cardiac arrest. The overall 30-day combined stroke/death rate was 2.52%, resulting in 1.61% event incidence in asymptomatic and 3.9% in symptomatic patients (P = ns). Logistic regression did not identify independent predictor of neurological events, except in the female gender.

CONCLUSION

This multicenter prospective registry shows that CAS performed with proximal flow blockage is safe and feasible also in octogenarians. Thirty days death/stroke rates are similar to those of the overall population and within the International guidelines.

Are symptomatic patients currently appropriate candidates for carotid artery stenting? Yes

Most of the currently published randomized trials (RCTs) for carotid artery stenting (CAS) versus carotid endarterectomy (CEA) on symptomatic patients have concluded that CAS is associated with outcomes that are inferior to those of CEA. However, before final decision making on the future of CAS, there are some major issues of concern. Randomized controlled trials condemning CAS suffer from major study flaws, rendering comparison with CEA ineffective. These trials are challenged by methodological gaps, underpowered results, old-fashioned equipment and underuse of cerebral protection devices or even of stents. On the other hand, physicians' experience in CAS has not been that much appreciated, whereas CEA has been widely performed during the last 30 years by experienced and fully trained vascular surgeons. CAS is a recently emerged treatment that cannot yet be standardized. No matter the final verdict on CAS, the procedure will never be for low volume practitioners. It is required that CAS be performed exclusively in high volume centers with specific dedicated experience and adequate training. Yet, optimistic results on CAS have been constantly reported from single, highly specialized CAS centers around the world. Regarding restenosis rates, they should be evaluated on the true need for re-intervention, since its clinical significance is still debated; but even when decision is undertaken to operate a restenosis, a repeat endovascular procedure is safe with reported complication rates < 1%. Concluding, vascular surgeons should be thoughtful about rejecting it as an alternative to CEA, because with advancing technology, vascular surgeons electing to stay away, and not perform CAS, will stay out of the "race."

Proximal endovascular occlusion for carotid artery stenting: results from a prospective registry of 1,300 patients

OBJECTIVES

This single-center registry presents the results of proximal endovascular occlusion (PEO) use in an unselected patient population.

BACKGROUND

In published multicenter registries, the use of PEO for carotid artery stenting (CAS) has been demonstrated to be safe and efficient in patient populations selected for anatomical and/or clinical conditions.

METHODS

From July 2004 to May 2009, 1,300 patients underwent CAS using PEO. Patients received an independent neurological assessment before the procedure and 1 h, 24 h, and 30 days after the procedure.

RESULTS

Procedural success was achieved in 99.7% of patients. In hospital, major adverse cardiac or cerebrovascular events included 5 deaths (0.38%), 6 major strokes (0.46%), 5 minor strokes (0.38%), and no acute myocardial infarction. At 30 days of follow-up, 2 additional patients died (0.15%), and 1 patient had a minor stroke (0.07%). The 30-day stroke and death incidence was 1.38% (n = 19). Symptomatic patients presented a higher 30-day stroke and death incidence when compared with asymptomatic patients (3.04% vs. 0.82%; p < 0.05). No significant difference in 30-day stroke and death rate was observed between patients at high (1.88%; n = 12) and average surgical risk (1.07; n = 7) (p = NS). Operator experience, symptomatic status, and hypertension were found to be independent predictors of adverse events.

CONCLUSIONS

The use of PEO for CAS is safe and effective in an unselected patient population. Anatomical and/or clinical conditions of high surgical risk were not associated with an increased rate of adverse events.