Protected carotid stenting in high-surgical-risk patients: The ARCHeR results

Flow arrest during carotid artery stenting with a distal embolic protection device: A single-center experience and clinical implications

OBJECTIVE

We aimed to investigate the incidence of flow arrest during carotid artery stenting (CAS) with filter-type embolic protection device (EPD), identify any predisposing factors for those situations, and contemplate intraprocedural precautionary steps.

METHODS

CAS was performed in 128 patients with 132 arteries using filter-type EPD. The characteristics of treated patients and arteries were compared between groups with and without flow arrest.

RESULTS

The incidence of flow arrest during CAS with filter-type EPD was 17.4%. In flow arrest group, cases of vulnerable plaques (p=0.02) and symptomatic lesions (p=0.01) were significantly more common, and there were more cases of debris captured by EPD in a planar pattern (p<0.01). Vulnerable plaques were significantly more common in the procedures showing a planar pattern than in the cases with other patterns (p<0.01). Flow arrest group showed a significantly higher rate of ischemic complications (p<0.05), although there were no significant periprocedural neurological changes. The planar pattern of captured debris in filter-type EPD was the only significant risk factor for flow arrest (adjusted odds ratio 88.44, 95% confidence interval 15.21-514.45, p<0.05).

CONCLUSIONS

Flow arrest during CAS with filter-type EPD is not uncommon and associated with increased ischemic complications. Symptomatic stenoses and vulnerable plaque are related to this event. The planar pattern of captured debris on the EPD was the only significant risk factor for the flow arrest. Clinicians must pay attention to the occurrence of flow arrest and react quickly when performing CAS.

Clinical Outcomes of Second- versus First-Generation Carotid Stents: A Systematic Review and Meta-Analysis

Background: Single-cohort studies suggest that second-generation stents (SGS; “mesh stents”) may improve carotid artery stenting (CAS) outcomes by limiting peri- and postprocedural cerebral embolism. SGS differ in the stent frame construction, mesh material, and design, as well as in mesh-to-frame position (inside/outside). Objectives: To compare clinical outcomes of SGS in relation to first-generation stents (FGSs; single-layer) in CAS. Methods: We performed a systematic review and meta-analysis of clinical studies with FGSs and SGS (PRISMA methodology, 3302 records). Endpoints were 30-day death, stroke, myocardial infarction (DSM), and 12-month ipsilateral stroke (IS) and restenosis (ISR). A random-effect model was applied. Results: Data of 68,422 patients from 112 eligible studies (68.2% men, 44.9% symptomatic) were meta-analyzed. Thirty-day DSM was 1.30% vs. 4.11% (p < 0.01, data for SGS vs. FGS). Among SGS, both Casper/Roadsaver and CGuard reduced 30-day DSM (by 2.78 and 3.03 absolute percent, p = 0.02 and p < 0.001), whereas the Gore stent was neutral. SGSs significantly improved outcomes compared with closed-cell FGS (30-day stroke 0.6% vs. 2.32%, p = 0.014; DSM 1.3% vs. 3.15%, p < 0.01). At 12 months, in relation to FGS, Casper/Roadsaver reduced IS (−3.25%, p < 0.05) but increased ISR (+3.19%, p = 0.04), CGuard showed a reduction in both IS and ISR (−3.13%, −3.63%; p = 0.01, p < 0.01), whereas the Gore stent was neutral. Conclusions: Pooled SGS use was associated with improved short- and long-term clinical results of CAS. Individual SGS types, however, differed significantly in their outcomes, indicating a lack of a “mesh stent” class effect. Findings from this meta-analysis may provide clinically relevant information in anticipation of large-scale randomized trials.

Survival and Prognostic Factors After Carotid Artery Stenting in Patients with Concomitant Coronary Disease

AIM: The aim of the study was to analyze the prognostic factors in patients after carotid artery stenting (CAS). METHODS: In 329 patients after CAS, the median survival (MS) and overall survival (OS) were calculated for a follow-up period of 2–101 months. All patients underwent coronary angiography before carotid stenting and, if indicated, coronary revascularization. Four groups of factors were analyzed: Carotid disease, coronary artery disease (CAD), underlying cardiac pathology, and concomitant diseases. RESULTS: MS in all patients was 86 months, OS at 1, 3, 5, and 9 years was - 94%, 85%, 73%, and 51%, respectively. Event free survival was 85 months. Log Rank-Mantel-Cox analysis demonstrated significantly reduced MS in 21 tested factors, most of them related to CAD. Two-step multifactorial Cox regression analysis defined only 7 of them as independent prognostic factors for the survival of patients after CAS: Left main stenosis, complete revascularization, late myocardial infarction, stroke, age over 70 years, valvular disease, and carotid score. CONCLUSION: Survival of patients after CAS is limited mainly by CAD and underlying cardiac pathology. Staged revascularization treatment strategy may improve the prognosis and survival of patients with both carotid and coronary disease.

Propensity score-matched analysis of 1-year outcomes of transcarotid revascularization with dynamic flow reversal, carotid endarterectomy, and transfemoral carotid artery stenting

OBJECTIVE

Initial studies showed no significant differences in perioperative stroke or death between transcarotid artery revascularization (TCAR) and carotid endarterectomy (CEA) and lower stroke/death rates after TCAR compared with transfemoral carotid artery stenting (TFCAS). This study focuses on the 1-year outcomes of ipsilateral stroke or death after TCAR, CEA, and TFCAS.

METHODS

All patients undergoing TCAR, TFCAS, and CEA between September 2016 and December 2019 were identified in the Vascular Quality Initiative (VQI) database. The latest follow-up was September 3, 2020. One-to-one propensity score-matched analysis was performed for patients with available 1-year follow-up data for TCAR vs CEA and for TCAR vs TFCAS. Kaplan-Meier survival and Cox proportional hazard regression analyses were used to evaluate 1-year ipsilateral stroke or death after the three procedures.

RESULTS

A total of 41,548 patients underwent CEA, 5725 patients underwent TCAR, and 6064 patients underwent TFCAS during the study period and had recorded 1-year outcomes. The cohorts were well-matched in terms of baseline demographics and comorbidities. Among 4180 TCAR vs CEA matched pairs of patients, there were no significant differences in 30-day stroke, death, and stroke/death. However, TCAR was associated with a lower risk of 30-day stroke/death/myocardial infarction (2.30% vs 3.25%; relative risk, 0.71; 95% confidence interval [CI], 0.55-0.91; P = .008), driven by a lower risk of myocardial infarction (0.55% vs 1.12%; hazard ratio [HR], 0.49; 95% CI, 0.30-0.81; P = .004). At 1 year, no significant difference was observed in the risk of ipsilateral stroke or death (6.49% vs 5.68%; HR, 1.14; 95% CI, 0.95-1.37; P = .157). Among 4036 matched pairs in the TCAR vs TFCAS group, TCAR was also associated with lower risk of perioperative stroke or death compared with TFCAS (1.83% vs 2.55%; HR, 0.72; 95% CI, 0.54-0.96; P = .027). At 1 year, the risks of ipsilateral stroke or death of TCAR and TFCAS were comparable (6.07% vs 7.07%; HR, 0.85; 95% CI, 0.71-1.01; P = .07). Symptomatic status did not modify the association in TCAR vs CEA. However, asymptomatic patients had favorable outcomes with TCAR vs TFCAS at 1 year (HR, 0.78; 95% CI, 0.62-0.98; P = .033).

CONCLUSIONS

In this propensity score-matched analysis, no significant differences in ipsilateral stroke/death-free survival were observed between TCAR and CEA or between TCAR and TFCAS. The advantages of TCAR compared with TFCAS seem to be mainly in the perioperative period, which makes it a suitable minimally invasive option for surgically high-risk patients with carotid artery stenosis. Larger studies, with longer follow-up and data on restenosis, are warranted to confirm the mid- and long-term benefits and durability of TCAR.

Transcervical carotid artery revascularization: A systematic review and meta-analysis of outcomes

OBJECTIVE

Carotid artery stenosis is considered a determinant factor for cerebrovascular events, estimated to be the cause of 10% to 20% of all ischemic strokes. Transcervical carotid artery revascularization (TCAR) has been offered as an alternative to transfemoral carotid artery stenting and carotid endarterectomy to treat carotid artery stenosis.

METHODS

We performed a systematic review and meta-analysis of prospective and retrospective studies reporting the outcomes of patients who had undergone TCAR for carotid artery stenosis. The incidence of periprocedural adverse events was calculated.

RESULTS

A total of 45 studies with 14,588 patients met the predefined eligibility criteria and were included in the present meta-analysis. The technical success rate was 99% (95% confidence interval [CI], 98%-99%). The reasons for technical failure included an inability to cross the lesion and/or failure to deploy the stent. Access site complications occurred in 2% of all cases (95% CI, 1%-2%; 30 studies). Overall, the incidence of cranial nerve (CN) injuries was very rare, with only 33 of 8994 patients experiencing neurologic deficits attributed to CN involvement. Bleeding complications were reported by 20 studies and occurred in 2% (95% CI, 1%-3%) of all cases. The overall periprocedural all-cause mortality and stroke rate was 0.5% and 1.3%, respectively. In-stent restenosis was observed in 4 of 260 patients (1.5%; 7 studies), and early (30-day) reocclusion or acute thrombosis of the target lesion occurred in 12 of 1243 patients (∼1%; 11 studies).

CONCLUSIONS

The results from the present study have provided significant evidence that TCAR is a very promising and safe carotid revascularization approach with favorable technical success rates associated with low periprocedural stroke and CN injury rates.

Factors associated with hemodynamic instability following carotid artery stenting

OBJECTIVE

Carotid artery stenting (CAS) is a major treatment option for carotid artery stenosis, and a recognized alternative to carotid endarterectomy (CEA). However, CAS-related hemodynamic instability occurs frequently and is a known major risk factor of associated complications. This study was undertaken to identify the risk factors of hemodynamic instability associated with CAS.

METHODS

We analyzed the medical records of 128 patients with carotid artery stenosis treated by CAS at our institution from 2014 to 2019 to identify the risk factors of hemodynamic instability after CAS. In addition, the incidences of hemodynamic instability, including bradycardia and hypotension, during and after the procedure were investigated.

RESULTS

Overall, periprocedural bradycardia requiring atropine occurred in 18 (14.1 %) of the 128 study subjects, and postprocedural persistent hypotension requiring vasopressors occurred in 15 (11.7 %). Risk-adjusted analysis showed carotid bulb involvement of a stenotic lesion was an independent risk factor of periprocedural bradycardia (OR 4.25, 95 % CI 1.34-13.40) and postprocedural persistent hypotension (OR 7.36, 95 % CI 1.86-29.12). However, though a preoperative regimen of ≥ 2 antihypertensives was found to be an independent protective factor against postprocedural persistent hypotension (OR 0.17, 95 % CI 0.04-0.81), it was not associated with periprocedural bradycardia (OR 0.37 95 % CI 0.08-1.60).

CONCLUSIONS

The risk of hemodynamic instability development is greater when a carotid stenotic lesion involves the carotid bulb, which cautions that careful evaluation is necessary. In addition, the receipt of antihypertensive regimens before CAS had a protective effect on persistent hypotension after CAS, but did not affect bradycardia.

Outcomes of Transcarotid Artery Revascularization and Carotid Endarterectomy at a Single Institution

BACKGROUND

Carotid endarterectomy (CEA) and carotid artery stenting (CAS) are accepted revascularization modalities to treat carotid artery stenosis. Higher incidences of perioperative adverse neurological events and death have been reported in patients with transfemoral CAS. Transcarotid artery revascularization (TCAR) is a newer operative technique that involves direct transcervical carotid access, mitigating aortic arch manipulation and minimizing the risk of embolic stroke via cerebral blood flow reversal. Perioperative stroke, myocardial infarction (MI), and death rates have been shown to be similar between TCAR and CEA, with TCAR having fewer complications. The objective of this study was to ascertain the safety and viability of TCAR by evaluating perioperative outcomes. We hypothesized that patients undergoing TCAR and CEA have equivalent outcomes.

METHODS

We performed a single-institution retrospective review of a prospectively maintained Vascular Quality Initiative database on patients who underwent TCAR or CEA between 2012 and 2019. A total of 66 TCAR cases from February 2018 to December 2019 and 501 CEA cases from January 2012 to December 2019 were reviewed. Preoperative, intraoperative, and postoperative characteristics as well as perioperative outcomes were captured for the statistical analyses.

RESULTS

From 2012 to 2019, 567 patients underwent TCAR or CEA. Patients who underwent TCAR were found to have higher rates of comorbidities compared with CEA. There were no procedure-related strokes in patients who underwent TCAR. There was no statistically significant difference between TCAR and CEA procedure-related strokes (0% vs. 1.0%, P = 0.42). There were 5 CEA procedure-related strokes because of technical problems resulting in thrombosis of the target vessels. Three patients who underwent CEA had strokes unrelated to the operations. Overall, there were no perioperative deaths, MI, cranial nerve injury (CNI), or hematoma in patients who underwent TCAR. There were no complications of surgical site infection, pseudoaneurysm, or arteriovenous fistula among patients who underwent TCAR or CEA.

CONCLUSIONS

This single-center retrospective analysis of TCAR and CEA for the treatment of carotid artery disease suggests TCAR can result in equivalent perioperative procedure-related stroke as CEA as well as equivalent incidence of perioperative complications including MI, CNI, hematoma, and death in selected patients or patients with proper anatomy. TCAR may be considered a safe, feasible carotid revascularization option for carotid artery stenosis.

The less invasive paradox, why carotid artery stenting is not suitable for the high-risk patient

Carotid artery stenosis causes significant morbidity and mortality accounting for approximately 8% of all ischaemic strokes. Carotid artery stenting (CAS) offers an endovascular alternative to carotid endarterectomy (CEA), suggested as a viable option in those deemed high-risk for open CEA due to comorbidities or operative technical considerations. A number of large randomised-controlled trials (RCTs) and meta-analysis comparing CAS vs. CEA in unselected patient populations support the conclusion that CAS is associated with a higher risk of stroke and CEA is associated with a higher risk of myocardial infraction. Initial promise for CAS in high-risk patients was demonstrated by The Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy (SAPPHIRE) trial that reported CAS was non-inferior to CEA. However, there is evidence to suggest age-related adverse outcome in patients undergoing CAS. There is limited evidence to suggest that CEA could be suitable even in patients deemed high-risk for medical or technical reasons. Further contemporary research on the use of CAS and CEA in high-risk patients is required to re-evaluate current guidelines and high-risk criterion. It is common for a composite outcome of death, ipsilateral stroke and MI which should be questioned as subsequent quality of life is likely to differ after suffering a stroke in comparison to MI. This literature review will discuss the current evidence for CAS and CEA interventions in unselected populations and high-risk patients with carotid disease requiring intervention.

Carotid endarterectomy remains safe in high-risk patients

OBJECTIVE

Carotid endarterectomy (CEA) is a proven intervention for stroke risk reduction in symptomatic and asymptomatic patients. High-risk patients are often offered carotid stenting to minimize the risk and optimize the outcomes. As a referral center for high-risk patients, we evaluated and analyzed our experience with high-risk CEA patients.

METHODS

We retrospectively reviewed consecutive patients who had undergone CEA at a tertiary referral center. The demographics, indications for surgery, physiologic and anatomic risk factors, intraoperative surgical management, perioperative complications, morbidity, and mortality were analyzed. The high-risk physiologic factors identified included an ejection fraction <30%, positive preoperative stress test results, and compromised pulmonary function test results. The high-risk patients included those requiring home oxygen, those with a partial pressure of oxygen of <60 mm Hg, and patients with a forced expiratory volume in 1 second of <30%. The high-risk anatomic factors identified included previous head and/or neck radiation, a history of ipsilateral neck surgery, contralateral nerve palsy, redo CEA, previous ipsilateral stenting, contralateral occlusion, contralateral CEA, nasotracheal intubation, and digastric muscle division. After propensity score matching, patients with and without high-risk physiologic and anatomic factors were compared. The primary outcomes were a composite of stroke, myocardial infarction, and 30-day mortality. The secondary outcomes were cranial injury and surgical site infection.

RESULTS

During a 10-year period, 1347 patients had undergone CEA at the Cleveland Clinic main campus. Of the 1347 patients, 1152 met the criteria for analysis. Propensity score matching found adequate matches for 424 high-risk patients, with 173 patients having at least one physiologic high-risk factor and 293 at least one anatomic high-risk factor. No significant differences were found in the primary composite outcome or any of its components. Overall, the stroke rate for the standard-risk and high-risk patients was 1.9% and 1.4%, respectively. The high-risk patients were significantly more likely to have experienced a cranial nerve injury, although most were temporary. When patients with one or multiple risk factors were analyzed, no significant difference was found in the primary composite outcome or any of its components. Patients with two or more risk factors were significantly more likely to have experienced a cranial nerve injury, with most being temporary.

CONCLUSIONS

In our large series, CEA remained a viable and safe surgical solution for patients with high-risk anatomic and physiologic risk factors, with acceptable stroke, myocardial infarction, and 30-day mortality rates.

Angioplasty and carotid artery stenting: clinical and morphological factors affecting long-term outcomes

Aim. To identify clinical and morphological factors affecting the longterm outcomes of endovascular angioplasty and carotid artery stenting.

Material and methods. The analysis included 198 patients after carotid artery stenting between 03.2014 and 05.2018. There were following inclusion criteria: (1) 50% of symptomatic or 70% of asymptomatic carotid artery stenosis of according to NASCET (North American Symptomatic Carotid Endarterectomy Trial) criteria; (2) follow-up for each patient for at least 1 year. Using the univariate and multivariate logistic regression, risk factors associated with adverse events were determined.

Results. The incidence of major adverse events during the 12-month follow-up was 9,6% (n=19), including 4 (2%) major and 6 (3%) minor strokes, 7 (3,5%) cases of transient ischemic attack; one (0,5%) patient had transient blindness and one (0,5%) died in the long-term follow-up period due to acute cerebrovascular accident in the target arterial territory. Also, 11 (5,6%) patients had restenosis >50% after 12-month follow-up. Multivariate analysis showed that long-term outcomes were significantly affected by: age >70 years (odds ratio (OR)=1,27, 95% confidence interval (CI): 1,07-1,61 (p=0,01); using of open-cell stents (OR=1,02, 95% CI: 1,01-1,03 (p=0,034)); contralateral stenosis (OR=1,28, 95% CI: 1,05-1,57 (p=0,01); lesion length >15 mm (OR=1,46, 95% CI: 1,12-1,89 (p=0,01)); residual stenosis <30% (OR=1,38, 95% CI: 1,09-1,49 (p=0,012)); complicated atherosclerotic plaque (OR=1,78, 95% CI: 1,21- 2,34 (p=0,007)). The development of in-stent restenosis was significantly influenced by factors such as the residual stenosis ><30% (OR=1,26, 95% CI: 1,1-1,65; p=0,017) and severe plaque calcification (OR=1,24, 95% CI: 1,04-1,31; p=0,02). Conclusion. The results obtained indicate the need for more careful preparation for endovascular intervention. Such factors as the use of open-cell stents, contralateral stenosis, lesion length >< 30% (OR=1,38, 95% CI: 1,09-1,49 (p=0,012)); complicated atherosclerotic plaque (OR=1,78, 95% CI: 1,21- 2,34 (p=0,007)). The development of in-stent restenosis was significantly influenced by factors such as the residual stenosis <30% (OR=1,26, 95% CI: 1,1-1,65; p=0,017) and severe plaque calcification (OR=1,24, 95% CI: 1,04-1,31; p=0,02).

Conclusion. The results obtained indicate the need for more careful preparation for endovascular intervention. Such factors as the use of open-cell stents, contralateral stenosis, lesion length >15 mm, and residual stenosis < 30% may be associated with an increased risk of adverse events.

Clinical outcomes of radiation-induced carotid stenosis: A systematic review and meta-analysis

OBJECTIVES

Clinical outcomes of radiation-induced carotid stenosis are still unclear. Therefore, a systematic review and meta-analysis is needed to evaluate the short- and long-term outcomes after interventions to treat radiation-induced carotid stenosis.

METHODS

PubMed, EMBASE, the Cochrane Library and Web of Science were searched from 1 January 2000 for relevant RCTs and observational studies which reported outcomes after carotid endarterectomy (CEA) and carotid angioplasty and stenting (CAS) for carotid stenosis induced by radiation. Risk of bias were assessed through different scales according to study design. I² statistic were used to evaluate the heterogeneity, and meta-regression were performed to investigate the source of heterogeneity. Visual inspection of funnel plots was used to judge publication bias.

RESULTS

A total of 26 studies with 1002 patients were included. CEA was performed in 364 patients and CAS in 638 patients. The overall estimated rate of short-term stroke was 0.19% (95% CI: 0-0.90%), and the rate of long-term stroke was 2.68 % (95% CI: 1.19-4.57%). The rate of cranial nerve injury in CEA group was significantly higher than that in CAS group [risk ratio (RR): 6.03, 95% CI: 1.63-22.22, P = .007]. The univariate regression analysis showed that the risk of stroke in CAS group were significantly higher than CEA group in both short- and long-term [incidence rate ratio (IRR): 3.62, 95% CI: 1.21-10.85, P = 0.22; IRR: 2.95, 95% CI: 1.02-8.59, P = .046, respectively].

CONCLUSIONS

This systematic review provided the worldwide profile of outcome of treatment for radiation-induced carotid stenosis, and also found that CEA can yield better results for these patients than CAS. Nonetheless, as large-scale studies have not yet been conducted, and there is a definite need for further studies in the future.

WIRION™ embolic protection system for carotid artery stenting and lower extremity endovascular intervention

Aim: To summarize all available literature regarding the Wirion™ embolic protection system (EPS) and present examples from our center. Materials & methods: A review of literture was performed about the utilization of Wirion EPS. Results: One study was identified investigating the outcomes of Wirion during carotid artery stenting. The study demonstrated 98.3% procedural success with stroke occurring in only 2.5%. Two single arm studies were identified investigating the efficacy of the Wirion filter during lower extremity endovascular interventions. The reported device success ranged from 95.1 to 97.3%. Conclusion: While carotid artery stenting should always be performed with adjunctive EPS in order to decrease the risk of cerebrovascular accidents, the routine use of EPS in femorpopliteal interventions remains an active area of investigation.

Double Filtration During Carotid Artery Stenting Using a Novel Post-Dilation Balloon With Integrated Embolic Protection

OBJECTIVES

This study evaluated the safety and performance of the Paladin System, a novel angioplasty balloon with an integrated embolic protection filter designed to increase embolic protection during post-dilation.

BACKGROUND

The risk of major adverse events during carotid artery stenting (CAS) is equivalent to carotid endarterectomy. However, the risk of minor stroke remains higher with CAS. Much of this risk occurs during post-stent dilation.

METHODS

A total of 106 patients were enrolled in 5 centers in Germany. The study's primary endpoint was all-cause death, myocardial infarction, and stroke at 30 days post-procedure. Pre- and post-procedural diffusion-weighted magnetic resonance imaging evaluated new ischemic lesions in 30 subjects. Filter histomorphometric analysis was performed in 23 patients. Retrospective analyses compared outcome rates to historical controls.

RESULTS

Device and procedural success rates were 100%. The combined major adverse event rate (death, myocardial infarction, and stroke) at discharge and at 30 days was 0% and 1.0%, respectively. The single adverse event was a stroke, which occurred at day 12 and was believed unrelated to the device or procedure. New ischemic lesions were found in 11 (36.7%) patients in the diffusion-weighted magnetic resonance imaging subset. New ipsilateral lesions were seen in 9 (30.0%) patients. Mean lesion volume per patient was 0.010 cm³. Debris was present in all filters, and approximately 90% of captured particles were <100 μm.

CONCLUSIONS

Use of the Paladin System for post-stent dilation during CAS appears safe, and it may effectively decrease the number of embolic particles reaching the brain, which may help reduce the risk of procedure-related stroke. (A Multi-Center Study to Evaluate Acute Safety and Clinical Performance of Paladin® Carotid Post-Dilation Balloon System With Integrated Embolic Protection; NCT02501148).

Carotid artery stenting versus endarterectomy for treatment of carotid artery stenosis

BACKGROUND

Carotid artery stenting is an alternative to carotid endarterectomy for the treatment of atherosclerotic carotid artery stenosis. This review updates a previous version first published in 1997 and subsequently updated in 2004, 2007, and 2012.

OBJECTIVES

To assess the benefits and risks of stenting compared with endarterectomy in people with symptomatic or asymptomatic carotid stenosis.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched August 2018) and the following databases: CENTRAL, MEDLINE, Embase, and Science Citation Index to August 2018. We also searched ongoing trials registers (August 2018) and reference lists, and contacted researchers in the field.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing stenting with endarterectomy for symptomatic or asymptomatic atherosclerotic carotid stenosis. In addition, we included RCTs comparing carotid artery stenting with medical therapy alone.

DATA COLLECTION AND ANALYSIS

One review author selected trials for inclusion, assessed trial quality and risk of bias, and extracted data. A second review author independently validated trial selection and a third review author independently validated data extraction. We calculated treatment effects as odds ratios (OR) and 95% confidence intervals (CI), with endarterectomy as the reference group. We quantified heterogeneity using the I² statistic and used GRADE to assess the overall certainty of evidence.

MAIN RESULTS

We included 22 trials involving 9753 participants. In participants with symptomatic carotid stenosis, compared with endarterectomy stenting was associated with a higher risk of periprocedural death or stroke (the primary safety outcome; OR 1.70, 95% CI 1.31 to 2.19; P < 0.0001, I² = 5%; 10 trials, 5396 participants; high-certainty evidence); and periprocedural death, stroke, or myocardial infarction (OR 1.43, 95% CI 1.14 to 1.80; P = 0.002, I² = 0%; 6 trials, 4861 participants; high-certainty evidence). The OR for the primary safety outcome was 1.11 (95% CI 0.74 to 1.64) in participants under 70 years old and 2.23 (95% CI 1.61 to 3.08) in participants 70 years old or more (interaction P = 0.007). There was a non-significant increase in periprocedural death or major or disabling stroke with stenting (OR 1.36, 95% CI 0.97 to 1.91; P = 0.08, I² = 0%; 7 trials, 4983 participants; high-certainty evidence). Compared with endarterectomy, stenting was associated with lower risks of myocardial infarction (OR 0.47, 95% CI 0.24 to 0.94; P = 0.03, I² = 0%), cranial nerve palsy (OR 0.09, 95% CI 0.06 to 0.16; P < 0.00001, I² = 0%), and access site haematoma (OR 0.32, 95% CI 0.15 to 0.68; P = 0.003, I² = 27%). The combination of periprocedural death or stroke or ipsilateral stroke during follow-up (the primary combined safety and efficacy outcome) favoured endarterectomy (OR 1.51, 95% CI 1.24 to 1.85; P < 0.0001, I² = 0%; 8 trials, 5080 participants; high-certainty evidence). The rate of ipsilateral stroke after the periprocedural period did not differ between treatments (OR 1.05, 95% CI 0.75 to 1.47; P = 0.77, I² = 0%). In participants with asymptomatic carotid stenosis, there was a non-significant increase in periprocedural death or stroke with stenting compared with endarterectomy (OR 1.72, 95% CI 1.00 to 2.97; P = 0.05, I² = 0%; 7 trials, 3378 participants; moderate-certainty evidence). The risk of periprocedural death or stroke or ipsilateral stroke during follow-up did not differ significantly between treatments (OR 1.27, 95% CI 0.87 to 1.84; P = 0.22, I² = 0%; 6 trials, 3315 participants; moderate-certainty evidence). Moderate or higher carotid artery restenosis (50% or greater) or occlusion during follow-up was more common after stenting (OR 2.00, 95% CI 1.12 to 3.60; P = 0.02, I² = 44%), but the difference in risk of severe restenosis was not significant (70% or greater; OR 1.26, 95% CI 0.79 to 2.00; P = 0.33, I² = 58%; low-certainty evidence).

AUTHORS' CONCLUSIONS

Stenting for symptomatic carotid stenosis is associated with a higher risk of periprocedural stroke or death than endarterectomy. This extra risk is mostly attributed to an increase in minor, non-disabling strokes occurring in people older than 70 years. Beyond the periprocedural period, carotid stenting is as effective in preventing recurrent stroke as endarterectomy. However, combining procedural safety and long-term efficacy in preventing recurrent stroke still favours endarterectomy. In people with asymptomatic carotid stenosis, there may be a small increase in the risk of periprocedural stroke or death with stenting compared with endarterectomy. However, CIs of treatment effects were wide and further data from randomised trials in people with asymptomatic stenosis are needed.

CEA vs. stent in patients with acute strokes: are they equally effective?

INTRODUCTION

Stroke is the 3rd leading cause of death worldwide with 15 million strokes annually. Extracranial carotid stenosis contributes to major stroke morbidity and mortality as a significant etiology of ischemic strokes. For acute stroke, in addition to optimal medical management, patients may be candidates for carotid endarterectomy and/or carotid stenting for secondary stroke reduction. This paper set out to review the data currently available regarding equivalency of the two intervention options.

EVIDENCE ACQUISITION

A comprehensive literature review was performed through PubMed and other sources using the key words carotid endarterectomy, carotid artery stent, acute stroke, symptomatic carotid stenosis, flow reversal, TCAR. Studies which solely evaluated patients with asymptomatic disease were ineligible for the study.

EVIDENCE SYNTHESIS

Review of landmark trials such as NASCET and CREST in addition to more recent studies demonstrates the effectiveness of surgical management with carotid endarterectomy of acute stroke. Carotid stenting has also been shown to have acceptable outcomes in certain patient populations.

CONCLUSIONS

Carotid endarterectomy continues to demonstrate effectiveness and safety for management of acute stroke, while carotid stenting has limitations. Carotid artery stenting has been shown to be non-inferior in some patient populations, but more recent and future technologic developments may expand the potential acceptable patient selection criteria.

Carotid artery stenting: Current state of evidence and future directions

Both carotid endarterectomy (CEA) and carotid artery stenting (CAS) are common treatments for carotid artery stenosis. Several randomized controlled trials (RCTs) have compared CEA to CAS in the treatment of carotid artery stenosis. These studies have suggested that CAS is more strongly associated with periprocedural stroke; however, CEA is more strongly associated with myocardial infarction. Published long-term outcomes report that CAS and CEA are similar. A reduction in complications associated with CAS has also been demonstrated over time. The symptomatic status of the patient and history of previous CEA or cervical radiotherapy are significant factors when deciding between CEA or CAS. Numerous carotid artery stents are available, varying in material, shape and design but with minimal evidence comparing stent types. The role of cerebral protection devices is unclear. Dual antiplatelet therapy is typically prescribed to prevent in-stent thrombosis, and however, evidence comparing periprocedural and postprocedural antiplatelet therapy is scarce, resulting in inconsistent guidelines. Several RCTs are underway that will aim to clarify some of these uncertainties. In this review, we summarize the development of varying techniques of CAS and studies comparing CAS to CEA as treatment options for carotid artery stenosis.

Analysis of the ROADSTER pivotal and extended-access cohorts shows excellent 1-year durability of transcarotid stenting with dynamic flow reversal

OBJECTIVE

We report the 1-year outcomes of the Safety and Efficacy Study for Reverse Flow Used During Carotid Artery Stenting Procedure (ROADSTER) multicenter trial. This trial introduced a novel transcarotid neuroprotection system (NPS), the ENROUTE transcarotid NPS (Silk Road Medical Inc, Sunnyvale, Calif). Postoperative results demonstrated that the use of the ENROUTE transcarotid NPS is safe and effective. The aim of this study was to evaluate the safety of transcarotid artery revascularization (TCAR) and to present the 1-year outcomes.

METHODS

This study is a prospective, single-arm clinical trial. Current enrollment occurs in 14 centers. Primary end points were incidence rates of ipsilateral stroke at 1 year after TCAR. Occurrence of stroke was ascertained by an independent Clinical Events Committee. Patients with anatomic or medical high-risk factors for carotid endarterectomy (CEA) were eligible to be enrolled in the ROADSTER trial.

RESULTS

Overall, 165 patients were included in the long-term follow-up (112 of 141 patients from the pivotal phase and 53 of 78 patients from the extended access). Mean age was 73.9 years (range, 42.1-91.3 years). Patients aged 75 years and older were 43.3% of the cohort. The majority of patients were white (92.7%) and male (75.2%). Most patients were asymptomatic (79.9%). Anatomic risk factors were distributed as follows: contralateral carotid artery occlusion (11.0%), tandem stenosis of >70% (1.8%), high cervical carotid artery stenosis (25.0%), restenosis after CEA (25.6%), bilateral stenosis requiring treatment (4.3%), and hostile neck (14.6%). Medical high-risk criteria included two-vessel coronary artery disease (14.0%) and severe left ventricular dysfunction with ejection fraction <30% (1.8%). In general, 43.3% of patients had at least one anatomic high-risk factor, whereas 29.9% of patients had medical high-risk factors. Both subsets of factors were present simultaneously in 26.8% of the cohort. At 1-year follow-up, ipsilateral stroke incidence rate was 0.6%, and seven patients (4.2%) died. None of the deaths were neurologic in origin.

CONCLUSIONS

TCAR with dynamic flow reversal had previously shown favorable 30-day perioperative outcomes. This excellent performance seems to extend to 1 year after TCAR as illustrated in this analysis. The promising results from the ROADSTER trial likely stem from the novel cerebral protection provided through the ENROUTE transcarotid NPS in comparison to distal embolic protection devices as well as the transcarotid approach's circumventing diseased aortic arch manipulation and minimizing embolization. TCAR offers a safe and durable revascularization option for patients who are deemed to be at high risk for CEA.

A Regional Experience with Carotid Endarterectomy in Patients with a History of Neck Radiation

BACKGROUND

Historically, a history of neck radiation has been considered as an anatomic risk factor for poor outcomes after carotid endarterectomy (CEA). However, this is based on small and primarily single institution reports with few comparative series. This study uses a regional quality database to compare perioperative outcomes of CEA in patients with and without a history of neck radiation (RAD and NORAD, respectively).

METHODS

The Vascular Study Group of New England database was queried for all CEA from 2003 to 2017. The RAD group included a history of neck radiation. Primary end points included perioperative stroke (30-day), myocardial infarction (MI) (in-hospital), death (30-day), a composite end point including major adverse events (MAEs: stroke, MI, and death), and long-term survival.

RESULTS

Overall, 18,832 patients underwent CEA (18,551 NORAD, 281 RAD). Baseline demographics differed in the following: the RAD group more frequently had a history of contralateral carotid artery stenting (1.4% vs. 0.3%, P = 0.009), anatomic high risk features (12.8% vs. 1.3%, P < 0.001), and contralateral carotid occlusion (5.3% vs. 2.4%, P = 0.005). The NORAD cohort comprised mostly women (38.9% vs. 29.5%, P < 0.001), had American Society of Anesthesiologists class 4 or 5 (8.0% vs. 4.6%, P = 0.035), had higher body mass index (28.3 ± 5.6 vs. 27.1 ± 5.4, P < 0.001), on a beta blocker preoperatively (68.0% vs. 62.3%, P = 0.042), and had major cardiovascular comorbidities including coronary artery disease (29.6% vs. 22.1%, P = 0.006). There were no differences in the percent stenosis, proportion symptomatic (37.4% vs. 34.2%, P = 0.259), use of preoperative antiplatelet agents or statins. Electroencephalography monitoring was more frequently used in RAD (54.5% vs. 46.0%, P = 0.005). There was no difference in perioperative complications, including stroke (RAD 0.4% vs. NORAD 0.7%, P > 0.999), MI (0.4% vs. 0.9%, P = 0.736), death (0.7% vs. 0.6%, P = 0.683), MAE (2.1% vs. 2.2%, P > 0.999), or long-term survival (79.9% vs. 85.0%, P = 0.357). When only symptomatic or asymptomatic stenosis was considered, there remained no difference in primary end points. However, perioperative neurologic events (transient ischemic attack or stroke) was higher in symptomatic RAD versus symptomatic NORAD (6.7% vs. 2.6%, P = 0.020).

CONCLUSIONS

This regional experience with CEA in RAD patients shows similar perioperative morbidity, mortality, and long-term survival when compared with CEA for standard surgical patients (NORAD). Symptomatic presentation was associated with higher perioperative neurologic events, but this was not reflected in stroke rates. RAD is not always a contraindication to CEA and select patients can expect outcomes comparable to standard surgical patients.

Independent Modular Filter for Embolic Protection in Carotid Stenting

BACKGROUND

Embolic protection during carotid artery stenting reduces the rate of thromboembolic events. The Wirion Embolic Protection System is used to deploy an independent distal filter using any 0.014″ guidewire. WISE study (Wirion Study Europe) evaluated the safety and performance of Wirion Embolic Protection System in patients undergoing carotid artery stenting.

METHODS AND RESULTS

A prospective, multicenter, nonrandomized, open-label, single-arm study of carotid artery stenting in high surgical risk patients was performed. The primary end point, a composite of death, stroke, and myocardial infarction at 30 days, was compared with performance goal derived from historical controls. Secondary end points were components of the primary end point and the device, angiographic, procedural, and clinical success rates. Preplanned interim analysis was performed on the first 120 patients. At interim analysis, the primary end point was significantly lower for the Wirion Embolic Protection System group, compared with historical data (3.3% versus 6.3%, respectively; P value =0.0008). Analysis of primary end point components in the WISE group, compared with the historical control group, shows numerically lower mortality (0% versus 1.7%, respectively; P=0.21), stroke (2.5% versus 4.6%, respectively; P=0.18), and myocardial infarction (0.8% versus 1.5%, respectively; P=0.50). Device, angiographic, procedural, and clinical success was achieved in 99.2%, 99.1%, 98.3%, and 96.6% of cases, respectively.

CONCLUSIONS

The data suggest that independent modular filter use in carotid artery stenting in high surgical risk patients is safe and effective. The outcomes suggest that use of an independent modular filter may be associated with a lower rate of embolic complications associated with carotid stent placement.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01783639.

An Algorithm for the Use of Embolic Protection During Atherectomy for Femoral Popliteal Lesions

OBJECTIVES

This study sought to identify an algorithm for the use of distal embolic protection on the basis of angiographic lesion morphology and vascular anatomy for patients undergoing atherectomy for femoropopliteal lesions.

BACKGROUND

Atherectomy has been shown to create more embolic debris than angioplasty alone. Distal embolic protection has been shown to be efficacious in capturing macroemboli; however, no consensus exists for the appropriate lesions to use distal embolic protection during atherectomy.

METHODS

Patients with symptomatic lower extremity peripheral artery disease treated with atherectomy and distal embolic protection were evaluated to identify potential predictors of DE. Plaque collected from the SilverHawk nose cone subset was sent to pathology for analysis to evaluate the accuracy of angiography in assessing plaque morphology.

RESULTS

Significant differences were found in lesion length (142.1 ± 62.98 vs. 56.91 ± 41.04; p = 0.0001), low-density lipoprotein (82.3 ± 40.3 vs. 70.9 ± 23.2; p = 0.0006), vessel runoff (1.18 ± 0.9 vs. 1.8 ± 0.9; p = 0.0001), chronic total occlusion (131 vs. 10; p = 0.001), in-stent restenosis (33 vs. 6; p = 0.0081), and calcified lesions (136 vs. 65; p < 0.001). In simple logistic regression analysis lesion length, reference vessel diameter, chronic total occlusion, runoff vessels, and in-stent restenosis were found to be strongly associated with macroemboli. Angiographic assessment of plaque morphology was accurate. Positive predictive value of 92.31, negative predictive value of 95.35, sensitivity of 92.31, and specificity of 95.35 for calcium; positive predictive value of 95.56, negative predictive value of 100, sensitivity of 100, and specificity of 92.31 for atherosclerotic plaque. Thrombus/in-stent restenosis was correctly predicted.

CONCLUSIONS

Chronic total occlusion, in-stent restenosis, thrombotic, calcific lesions >40 mm, and atherosclerotic lesions >140 mm identified by peripheral angiography necessitate concomitant filter use during atherectomy to prevent embolic complications.

Hemorrhagic and ischemic outcomes of Heparin vs. Bivalirudin in carotid artery stenting: A meta-analysis of studies

INTRODUCTION

Bivalirudin, has been shown to have comparable efficacy and better safety profile when compared to unfractionated heparin (UFH) in percutaneous coronary interventions. Bivalirudin's safety in carotid artery stenting (CAS) was associated with better outcomes than heparin in some studies. In this Meta analysis we examine the hemorrhagic and ischemic outcomes associated with Bivalirudin compared to UFH during CAS.

METHODS

A comprehensive literature search was conducted with the electronic databases MEDLINE, EMBASE, and CENTRAL. Random-effects meta-analysis method was used to pool risk ratio (RR) for both Heparin and Bivalirudin with 95% confidence interval (CI). Study outcomes included hemorrhagic complications; major/minor bleeding and intracranial hemorrhage (ICH) as well as ischemic complications including ischemic stroke, myocardial infarction, and 30 day mortality.

RESULTS

A total of four studies were included enrolling 7,784 patients. Compared to UFH, Bivalirudin was associated with significantly lower major bleeding events with a relative risk (RR) of 0.53 (95% CI: 0.35-0.80; I²  = 0%). Minor bleeding events were significantly lower in the Bivalirudin group with a RR of 0.41 (95% CI: 0.2-0.82; I²  = 0%). Looking into other outcomes, there were no significant differences between anticoagulation strategies in terms of ischemic stroke (RR 0.8, with 95% CI: 0.60-1.06), intracranial hemorrhage (RR 0.73 with 95% CI: 0.27-1.98), myocardial infarction (RR 1.01 with 95% CI: 0.59-1.73) or 30 day mortality (RR 0.83 with 95% CI: 0.47-1.47).

CONCLUSION

Compared to UFH, Bivalirudin is associated with lower bleeding risk when used during CAS. © 2016 Wiley Periodicals, Inc.

Clinical results of carotid artery stenting versus carotid endarterectomy

Objective:

To review our results of carotid artery stenting (CAS) and carotid endarterectomy (CEA).

Methods:

We evaluated the medical records of patients undergoing carotid artery revascularization procedure, between 2001 and 2013 in Baskent University Hospital, Ankara, Turkey. Carotid artery stenting or CEA procedures were performed in patients with asymptomatic carotid stenosis (≥70%) or symptomatic stenosis (≥50%). Demographic data, procedural details, and clinical outcomes were recorded. Primary outcome measures were in 30-day stroke/transient ischemic attacks (TIA)/amaurosis fugax or death. Secondary outcome measures were nerve injury, bleeding complications, length of stay in hospital, stroke, restenosis (ICA patency), and all-cause death during long-term follow-up.

Results:

One hundred ninety-four CEA and 115 CAS procedures were performed for symptomatic and/or asymptomatic carotid artery stenosis. There is no significant differences 30-day mortality and neurologic morbidity between CAS (13%) and CEA procedures (7.7%). Length of stay in hospital were significantly longer in CEA group (p=0.001). In the post-procedural follow up, only in symptomatic patients, restenosis rate was higher in the CEA group (p=.045). The other endpoints did not differ significantly.

Conclusions:

Endovascular stent treatment of carotid artery atherosclerotic disease is an alternative for vascular surgery, especially for patients that are high risk for standard CEA. The increasing experience, development of cerebral protection systems and new treatment protocols increases CAS feasibility.

Long-Term Outcomes of Carotid Artery Stenting in Clinical Practice

Background—

There is a lack of long-term data and data outside of controlled clinical trials in carotid artery stenting. Thus, we sought to evaluate the long-term effectiveness in stroke prevention by carotid artery stenting in a large number of patients in a real-world setting.

Methods and Results—

The present work represents an all-comer registry with a strict, prospectively designed, follow-up protocol, including an independent pre- and postprocedural neurological assessment. Between November 1999 and March 2015, 1000 procedures in 901 patients were consecutively performed in a single center. Mean age was 71±9 years, and symptomatic stenosis was present in 262 patients (29.1%). The population was also characterized by a high comorbidity: 289 patients (32.1%) would have been excluded according to the CREST protocol (Carotid Revascularization Endarterectomy Versus Stent Trial). The median length of follow-up was 5.5 (interquartile range, 2.6–7.9) years and complete in 93% of the patients. The rate of the primary end point (composite of stroke, death, and myocardial infarction [major adverse cardiac or cerebrovascular event] by day 30 plus ipsilateral stroke beyond 30 days) was 6.9% (9.9% in symptomatic versus 5.7% in asymptomatic patients; P =0.03). The rate was higher in CREST ineligible than in CREST eligible patients (11.4% versus 4.9%; P =0.001).

Conclusions—

Long-term stroke prevention by carotid artery stenting is effective in experienced centers. A high percentage of patients who would have been excluded from controlled clinical trials undergoes carotid artery stenting in daily clinical practice. However, these patients have a substantially higher risk for an acute major adverse cardiac or cerebrovascular event.

Diagnostic vascular ultrasonography with the help of color Doppler and contrast-enhanced ultrasonography

The use of ultrasonography and especially of contrast-enhanced ultrasonography (CEUS) in the diagnosis of vascular pathologies before and after interventions has significantly increased over the past years due to the broader availability of modern ultrasound systems with CEUS capabilities and more trained user experience in this imaging modality. For the preinterventional and postinterventional work-up of carotid diseases, duplex ultrasound as well as CEUS have been established as the standard-of-care examination procedures for diagnosis, evaluation, and follow-up. In addition to its use for carotid arterial diseases, ultrasonography has also become the primary modality for the screening of vascular pathologies. This review describes the most common pathologies found in ultrasonography of the carotid arteries, the abdominal aorta, and the femoral arteries.

Risk Factors for Developing Postprocedural Microemboli following Carotid Interventions

Purpose:

To determine risk factors predictive of microemboli found on diffusion-weighted magnetic resonance imaging (DW-MRI) following carotid angioplasty and stenting (CAS) with distal protection and carotid endarterectomy (CEA).

Methods:

A retrospective review was conducted of all carotid interventions at a single institution between 2004 and 2006. In that time frame, 64 carotid interventions (34 CAS, 30 CEA) were performed in 63 male patients (mean age 69.5 years, range 52 to 91) with DW-MRI scans available for review. Patient characteristics, including age, gender, smoking history, diabetes mellitus, hypertension, hyperlipidemia, obesity (body mass index >30), coronary artery disease (CAD), chronic obstructive pulmonary disease, peripheral vascular disease, and atrial fibrillation, were documented. For the CAS patients, anatomical and procedural characteristics, including fluoroscopy time, contrast volume, performance of an arch angiogram, and lesion anatomy, were recorded. Bivariate analyses were performed to determine which parameters were associated with the occurrence of acute postprocedural microemboli found on DW-MRI by 2 blinded neuroradiologists.

Results:

Twenty-four (71%) of the 34 CAS patients and 1 (3%) of the 30 CEA patients demonstrated new cerebral microemboli postoperatively. In the bivariate analyses of all patient, anatomical, and procedural characteristics, only a history of CAD was associated with an increased risk of microemboli; 20 (80%) of the 25 patients who had postprocedure microemboli had CAD compared to 18 (46%) of 39 patients without microemboli (p=0.007). Twenty (53%) of the 38 (59%) patients with CAD developed microemboli compared to 5 (19%) of the 26 patients without CAD (p=0.007). All other patient, procedural, and anatomical characteristics were not found to be independent risk factors predictive of postprocedure microemboli.

Conclusion:

CAS with distal protection carries a significantly greater risk for developing new microemboli compared to CEA. Of all the risk factors analyzed, only a history of CAD emerged as an independent risk factor for the development of microemboli following carotid intervention. This finding may influence the decision to perform CAS in patients deemed high risk solely due to the presence of CAD.

Endovascular Rescue of a Fused Monorail Balloon and Cerebral Protection Device

Purpose:

To present a case of successful endovascular retrieval of a monorail predilation balloon fused to an embolic protection device (EPD) in the distal internal carotid artery (ICA) of a high-risk symptomatic patient.

Case Report:

A 60-year-old man with documented systemic atherosclerotic disease had a severe (>70%) restenosis in the left ICA 3 years after endarterectomy. He was scheduled for carotid artery stenting (CAS) with cerebral protection; however, he developed unstable angina and was transferred to our facility, where the admitting team decided that staged CAS followed by coronary bypass grafting would be the best option. During the CAS procedure, a 6-mm AccuNet filter was passed across the lesion via a 6-F carotid sheath and deployed in the distal ICA without incident. However, the 4-×20-mm predilation monorail balloon was then advanced without visualizing the markers, resulting in inadvertent aggressive interaction that trapped the balloon's tip in the filter. Several maneuvers to separate the devices were unsuccessful. Finally, the filter/balloon combination was moved gently retrograde until the balloon was straddling the subtotal ICA lesion. The lesion was dilated to 4 mm with the balloon, and the sheath was gently advanced across the lesion as the balloon was deflated. Angiography excluded interval occlusion of the filter from the embolic debris during the aforementioned aggressive maneuvers and documented antegrade flow. The filter was slowly withdrawn into the 6-F sheath with simultaneous aspiration. A second 6-mm filter was deployed, and the procedure was completed satisfactorily. The patient did well, with no neurological sequelae.

Conclusion:

EPDs are an essential in carotid artery stenting and, keeping in mind the potential risks associated with their use, will help the operator avoid complications such as this one.

TCD Evaluation before and after Stenting in Patients with Severe Primary Carotid Artery Stenosis versus Restenosis

Purpose:

To evaluate cerebral hemodynamics before and after carotid angioplasty and stenting (CAS) using transcranial Doppler (TCD).

Methods:

Sixty-eight patients (52 men; mean age 69±9.5 years) with severe carotid stenosis (83.4%±10.2%) were examined by TCD before and 2 months after CAS. Thirty-two (47%) patients had primary carotid stenosis and 36 (53%) had restenosis after carotid endarterectomy (CEA). A broad TCD protocol was employed to estimate cerebral hemodynamics, including assessment of velocities (V) and asymmetry of cerebral blood flow velocity (CBFV) in the middle cerebral artery, (MCA) anterior cerebral artery (ACA), and basilar artery (BA); the pulsatility indexes; and flow acceleration.

Results:

Ipsilateral MCA mean velocities before stenting were 46.3±12.6 cm/s in the primary stenosis group and 47.1±12.3 cm/s in restenosis group; after stenting, the velocities were 53.8±12.1 and 52.7±9.6 cm/s, respectively (p<0.005 for both groups). MCA asymmetry by Vmean before CAS was higher in the primary stenosis group (27.6%±2.4% versus 19.8%±2.3%, p<0.05). After stenting, this index was significantly lower in both groups: 16.4%±2.4% and 12.3%±2.3%, respectively (p<0.0001 for each group). All other TCD parameters improved significantly in both groups after CAS as well (p<0.05), showing the strong hemodynamic effect of this procedure.

Conclusion:

CAS effectively improves cerebral hemodynamics in patients with severe primary and restenosis of the internal carotid artery.

Carotid Artery Stenting with Distal Protection Using the Carotid Wallstent and Filterwire Neuroprotection: Single-Center Experience of 380 Cases with Midterm Outcomes

Emerging data have supported the clinical efficacy of carotid artery stenting (CAS) in stroke prevention in high-risk surgical patients. This study was performed to evaluate the midterm clinical outcome of CAS using the Carotid Wallstent and FilterWire distal protection (both Boston Scientific, Natick, MA) at an academic institution. Risk factors for in-stent restenosis (ISR) were also analyzed. Clinical variables and treatment outcome of high-risk patients who underwent Carotid Wallstent placement with FilterWire EX/EZ neuroprotection were analyzed during a recent 54-month period. Three hundred eighty CAS procedures were performed in 354 patients. Technical success was achieved in 372 cases (98%), and symptomatic lesions existed in 85 (24%) patients. No patient experienced periprocedural mortality or neuroprotective device–related complication. The 30-day stroke and death rate was 2.7%, and the overall complication rate was 6.9%. The overall major or fatal stroke rates in symptomatic and asymptomatic patients were 4.6% and 1.3%, respectively (not significant). The overall stroke and death rates between the symptomatic and asymptomatic groups were 5.8% and 2.4%, respectively (not significant). The median follow-up period was 29 months (range 1–53 months). With Kaplan-Meier analysis, the rates of freedom from 60% or greater ISR after CAS procedures at 12, 24, 36, and 48 months were 97%, 94%, 92%, and 90%, respectively. The rates of freedom from all fatal and nonfatal strokes at 12, 24, 36, and 48 months were 97%, 91%, 89%, and 85%, respectively. Multivariable analysis of significant univariate predictors identified that postendarterectomy stenosis (odds ratio [OR] 3.98, p = .02) and multiple stent placement (OR 3.68, p = .03) were independent predictors of ISR. Our study yielded favorable short-term and midterm clinical results using Carotid Wallstent with FilterWire neuroprotection. Late follow-up results showed low rates of fatal and nonfatal stroke and favorable ISR rates compared with other carotid stent trials. Postendarterectomy and multiple stent placement were associated with subsequent ISR.

Association of CYP2C19 Polymorphisms with the Clinical Efficacy of Clopidogrel Therapy in Patients Undergoing Carotid Artery Stenting in Asia

The CYP2C19 gene plays a detrimental role in the metabolism of clopidogrel. This study aimed to investigate the association between CYP2C19 polymorphisms and the clinical efficacy of clopidogrel therapy in patients who have undergone carotid artery stenting (CAS). CYP2C19 genotype screening was performed on 959 ischemic stroke patients. Of these patients, 241 who had undergone CAS were enrolled in the study. They were all followed up for 1 year after stent surgery, and the primary clinical end-points were ischemic events. The frequencies of the CYP2C19*2 and *3 alleles among the 959 patients were 31.80% and 5.06%, respectively. Regarding the 241 participants who had undergone CAS, multivariate Cox regression analysis showed that the CYP2C19 loss-of-function (LOF) alleles (*2 and *3) were risk factors for post-CAS prognosis. Within 1 year of follow-up, the patients carrying the CYP2C19 LOF alleles were more likely to experience ischemic events than those carrying none. The occurrence of ischemic events did not significantly differ between the *2 and *3 allele carriers. Our results suggest that CYP2C19 LOF alleles (*2 and *3) significantly impact the prognosis of patients on clopidogrel therapy after CAS and that the CYP2C19*2 and CYP2C19*3 alleles have the same effects on prognosis.

Preoperative and Postoperative Evaluation of New Double Mesh Carotid Stents with Contrast-Enhanced Ultrasound and Diffusion-Weighted Imaging

In this case series, we selected 4 patients with asymptomatic severe carotid stenosis due to unstable plaques, which were identified with contrast-enhanced ultrasound. These patients underwent carotid stenting with a new generation double mesh stent. Diffusion-weighted magnetic resonance imaging (DW-MRI) was executed before and after the procedure to detect early cerebral microembolizations. No early neurological complications occurred nor cerebral microembolizations were detected at DW-MRI. New double mesh carotid stents appear to be a safe option also in asymptomatic patients with unstable plaques at high risk for surgery.

Percutaneous Aspiration Thrombectomy for Arterial Thromboembolism during Infrainguinal Endovascular Recanalization

Objectives

To evaluate the efficacy of percutaneous aspiration thrombectomy (PAT) for infrainguinal arterial thromboembolism in patients undergoing endovascular recanalization (EVR) and to investigate the predictors for thromboembolic complications.

Materials and Methods

In total, 23 patients (23 limbs) who underwent PAT for thromboembolism (PAT group, PG) during EVR and 237 patients (302 limbs) who underwent successful EVR without thromboembolic complications (control group, CG) were enrolled. Immediate post-operation and follow-up outcomes were compared between the two groups. Multivariate analysis was performed to identify the predictors of thromboembolic complications. Technical success of PAT was defined as achievement of <30% residual stenosis and restoration of mTIMI grade 3.

Results

The technical success rate was 95.7% in PG. After intervention, the ankle–brachial index (ABI), restoration of blood flow and improvement in dorsal/plantar arterial pulse score showed no significant differences between PG and CG. During follow-up in PG, a sustained ABI improvement was observed in 63.6% (70.9% in CG), an improvement in walking distance in 68.8% (79.9% in CG,), ulcer healing in 75.0% (71.7% in CG) and restenosis/occlusion in 31.8% (25.2% in CG). The limb salvage rate was 100% in PG (96.0% in CG), and pain relief was observed in 66.7% patients with critical limb ischaemia (81.6% in CG). Superficial femoral artery involvement [0.233; 95% confidence interval (CI), 0.108–0.461; P < 0.001], de-novo lesion occlusion (683.8; 95% CI, 36.5–12804.6; P < 0.001) and intraluminal angioplasty (118.4; 95% CI, 8.0–1758.0; P = 0.001) was associated with high incidence of thromboembolism.

Conclusion

PAT is a safe and effective treatment for thromboembolism during infrainguinal arterial EVR. SFA involvement, de-novo lesion occlusion and intraluminal angioplasty may be predictors of thromboembolic complications.

Selecting an appropriate surgical treatment instead of carotid artery stenting alone according to the patient's risk factors contributes to reduced perioperative complications in patients with internal carotid stenosis: a single institutional retrospective analysis

This retrospective study was aimed to compare the perioperative complications for internal carotid artery stenosis (ICS) in a Japanese single institute between the use of carotid artery stenting (CAS) alone or the use of an appropriate individualized treatment method allowing either carotid endarterectomy (CEA) or CAS based on patient risk factors. Based on the policy at our hospital, only CAS was performed on patients (n = 33) between January 2005 and November 2009. From December 2009 to December 2012, either CEA or CAS (tailored treatment) was selected for patients (n = 61) based on individual patient risk factors. CEA was considered the first-line treatment in all cases. In high-risk CEA cases, CAS was performed instead (n = 11), whereas in low-risk CEA cases, CEA was performed (n = 19). Further, in moderate-risk CEA cases based on own criteria, CAS was considered first, whereas for high-risk CAS cases, CEA was performed (n = 17). For low-risk CAS cases, CAS was performed (n = 9). Perioperative clinical complications (any stroke, myocardial infarction, or death within 30 days) were compared between both periods. Significantly reduced perioperative complications were observed during the tailored period (4/61 sites, 6.6%) as compared with the CAS period (8/33 sites, 24.2%) [Fisher’s exact test p = 0.022; odds ratio, 4.56 (CAS/tailored); 95% confidence interval, 1.26–16.5]. Selecting an appropriate individualized treatment method according to patient risk factors, as opposed to adhering to a single treatment approach such as CAS, may contribute to improved overall outcomes in patients with ICS.

The development of carotid stent material

Endovascular angioplasty with stenting is a promising option for treating carotid artery stenosis. There exist a rapidly increasing number of different stent types with different materials. The bare-metal stent is the most commonly used stent with acceptable results, but it leaves us with the problems of thrombosis and restenosis. The drug-eluting stent is a breakthrough as it has the ability to reduce the restenosis rate, but the problem of late thrombosis still has to be addressed. The biodegradable stent disappears after having served its function. However, restenosis and degradation rates remain to be studied. In this article, we review every stent material with its characteristics, clinical results and complications and point out the standards of an ideal carotid stent.