Anatomic criteria in the selection of treatment modality for atherosclerotic carotid artery disease

Outcomes of transcarotid artery revascularization: A systematic review

BACKGROUND

Ischemic stroke and disability caused by carotid artery stenosis have always been worldwide problems. At present, carotid endarterectomy (CEA) and transfemoral carotid artery stenting (TFCAS) have been commonly used to treat carotid artery stenosis. Recently, transcarotid artery revascularization (TCAR) seems to be another option.

METHODS

We searched PubMed and Embase to find literatures comparing TCAR with TFCAS and CEA. The primary outcomes were stroke, myocardial infarction (MI), transient ischemic attack (TIA), death, cranial nerve injure (CNI), and operative time. Secondary outcomes were stroke, death, MI in the elderly; cost; radiation; and entry site complication.

RESULTS

Initial search of the literature included 165 articles, of which 12 studies were chosen in the end. These studies demonstrated high technical success rate of TCAR. Patients who received TCAR had lower risks of death, stroke/death and less radiation exposure compared to TFCAS. In meta analysis, the risk of stroke was significantly lower in TCAR group than TFCAS (OR 0.63; 95%CI 0.47-0.85). And there was no significant difference in TIA and MI. TCAR was associated with shorter operative time, lower risk of CNI and less blood loss compared to CEA. In older patients, the effect of TCAR was significantly better than that of TFCAS.

CONCLUSION

TCAR is associated with a lower risk of perioperative stroke compared to TFCAS. TCAR is also associated with shorter operative time, lower risk of CNI and less blood loss compared to CEA. TCAR may be a promising treatment option besides TFCAS and CEA.

Seven years of the transcarotid artery revascularization surveillance project, comparison to transfemoral stenting and endarterectomy

OBJECTIVE

This study utilizes the latest data from the Vascular Quality Initiative (VQI), which now encompasses over 50,000 transcarotid artery revascularization (TCAR) procedures, to offer a sizeable dataset for comparing the effectiveness and safety of TCAR, transfemoral carotid artery stenting (tfCAS), and carotid endarterectomy (CEA). Given this substantial dataset, we are now able to compare outcomes overall and stratified by symptom status across revascularization techniques.

METHODS

Utilizing VQI data from September 2016 to August 2023, we conducted a risk-adjusted analysis by applying inverse probability of treatment weighting to compare in-hospital outcomes between TCAR vs tfCAS, CEA vs tfCAS, and TCAR vs CEA. Our primary outcome measure was in-hospital stroke/death. Secondary outcomes included myocardial infarction and cranial nerve injury.

RESULTS

A total of 50,068 patients underwent TCAR, 25,361 patients underwent tfCAS, and 122,737 patients underwent CEA. TCAR patients were older, more likely to have coronary artery disease, chronic kidney disease, and undergo coronary artery bypass grafting/percutaneous coronary intervention as well as prior contralateral CEA/CAS compared with both CEA and tfCAS. TfCAS had higher odds of stroke/death when compared with TCAR (2.9% vs 1.6%; adjusted odds ratio [aOR], 1.84; 95% confidence interval [CI], 1.65-2.06; P < .001) and CEA (2.9% vs 1.3%; aOR, 2.21; 95% CI, 2.01-2.43; P < .001). CEA had slightly lower odds of stroke/death compared with TCAR (1.3% vs 1.6%; aOR, 0.83; 95% CI, 0.76-0.91; P < .001). TfCAS had lower odds of cranial nerve injury compared with TCAR (0.0% vs 0.3%; aOR, 0.00; 95% CI, 0.00-0.00; P < .001) and CEA (0.0% vs 2.3%; aOR, 0.00; 95% CI, 0.0-0.0; P < .001) as well as lower odds of myocardial infarction compared with CEA (0.4% vs 0.6%; aOR, 0.67; 95% CI, 0.54-0.84; P < .001). CEA compared with TCAR had higher odds of myocardial infarction (0.6% vs 0.5%; aOR, 1.31; 95% CI, 1.13-1.54; P < .001) and cranial nerve injury (2.3% vs 0.3%; aOR, 9.42; 95% CI, 7.78-11.4; P < .001).

CONCLUSIONS

Although tfCAS may be beneficial for select patients, the lower stroke/death rates associated with CEA and TCAR are preferred. When deciding between CEA and TCAR, it is important to weigh additional procedural factors and outcomes such as myocardial infarction and cranial nerve injury, particularly when stroke/death rates are similar. Additionally, evaluating subgroups that may benefit from one procedure over another is essential for informed decision-making and enhanced patient care in the treatment of carotid stenosis.

Feasibility and Intermediate Results of Transcarotid Revascularization with a Prosthetic Conduit

BACKGROUND

Transcarotid artery revascularization (TCAR) is a hybrid technique with excellent initial outcomes. The technical success and safety of TCAR is heavily dependent on an anatomically suitable common carotid artery (CCA). Many patients do not meet anatomic criteria and therefore are not eligible for this therapy. We sought to extend the eligibility of TCAR to patients with unfavorable CCA anatomy via the adoption of a prosthetic arterial conduit.

METHODS

A single-center retrospective study of patients with critical carotid artery stenosis who underwent TCAR via a prosthetic conduit between June 2019 and October 2021 was performed. All patients in the study were considered high-risk for carotid endarterectomy based on anatomic features, such as restenosis post-carotid endarterectomy and neck radiation. Unfavorable CCA anatomy was defined as a clavicle to carotid bifurcation distance <5 cm, a CCA diameter <6 mm, and/or significant atherosclerotic disease at the intended arterial access site. The primary outcome of interest was technical success. Secondary outcomes included perioperative complications, intermediate and long-term patency, intermediate and long-term stroke and/or mortality and in-hospital length of stay. Follow-up ranged from 1 to 29 months.

RESULTS

Eight patients underwent 10 TCAR procedures via a prosthetic conduit. A total of 2 procedures (20%) were performed on female patients and 8 procedures (75%) were performed on male patients. The mean age was 65 years old (standard deviation 11 years). Technical success was 100%. The 30-day ipsilateral stroke rate was 0%. The 30-day patency was 90%. There was no re-exploration for hemorrhage and 30 day mortality was 0%.

CONCLUSIONS

TCAR is an excellent option for carotid artery revascularization. Unfavorable CCA anatomy has limited its applicability. TCAR via a prosthetic conduit has the potential to expand eligibility for this promising therapy.

Discrepancies in clavicle-to-carotid bifurcation length measurements for transcarotid artery revascularization using different imaging modalities

OBJECTIVE

Transcarotid artery revascularization (TCAR) has emerged as an effective method for carotid artery stenting. However, anatomic eligibility for TCAR is most often limited by an inadequate clavicle-to-carotid bifurcation length of <5 cm. Preoperative clavicle-to-carotid bifurcation distances may be underestimated when using conventional straight-line measurements on computed tomographic angiography (CTA) imaging. We therefore compared clavicle-to-carotid bifurcation lengths as measured by straight-line CTA, center-line CTA, and intraoperative duplex ultrasound (US), to assess potential differences.

METHODS

We conducted a single-center, retrospective review of consecutive TCAR procedures performed between 2016 and 2019 for atherosclerotic carotid disease. For each patient, we compared clavicle-to-carotid bifurcation lengths measured by straight-line CTA, center-line CTA using TeraRecon image reconstruction, and intraoperative duplex US with neck extension and rotation. We further assessed patient and imaging characteristics in individuals with a ≥0.5 cm difference among the measurement methods. In particular, common carotid artery (CCA) tortuosity, defined as the inability to visualize the entire CCA from clavicle to carotid bifurcation on both a single coronal and sagittal imaging cut, was examined as a contributing factor for these discrepancies.

RESULTS

Of the 70 TCAR procedures identified, 46 had all three imaging modalities available for review. The median clavicle-to-carotid bifurcation length was found to be 6.4 cm (interquartile range [IQR], 5.4-6.7 cm) on straight-line CTA, 7.0 cm (IQR, 6.0-7.5 cm) on intraoperative duplex US, and 7.2 cm (IQR, 6.5-7.5 cm) on center-line CTA (P < .001). Patients with a ≥0.5 cm difference between their straight-line CTA and either their intraoperative duplex US or center-line CTA measurements were more likely to have tortuous CCAs (60.0% vs 19.1%; P = .01; 51.4% vs 0.0%; P = .01). There were no notable differences in age, gender, prior neck/cervical spine surgery, or neck immobility among these individuals. In patients with tortuous CCAs, duplex US and center-line CTA measurements added 1.0 cm (IQR, 0.6-1.5 cm) and 1.1 cm (IQR, 0.9-1.6 cm) more in length than straight-line CTA measurements, respectively. There was a strong linear correlation between the additional lengths provided by duplex US measurements and those provided by center-line CTA measurements for each individual within the tortuous CCA group (r = 0.83).

CONCLUSIONS

The use of straight-line CTA during preoperative planning can underestimate the clavicle-to-carotid bifurcation lengths in patients undergoing carotid revascularization, particularly in those with tortuous CCAs. Both duplex US performed with extended-neck surgical positioning and center-line CTA provide similar and longer carotid length measurements, and should be utilized in patients with tortuous carotid vessels to better determine TCAR anatomic eligibility.

Delayed Migration of Tapered Open-Cell Design Carotid Stent: A Case Report

We present a case of delayed migration of an open-cell design carotid stent, which is a rare complication following carotid artery stenting (CAS). A 65-year-old patient with carotid artery stenosis underwent CAS with an open-cell stent, initially achieving successful deployment. However, 4 months later, the stent migrated and resulted in restenosis. The patient underwent balloon angioplasty and received an additional stent, leading to improved blood flow. The rarity of stent migration, particularly in the absence of risk factors, highlights the need for clinicians to be vigilant and consider early imaging follow-up for patients at risk of this complication after CAS.

Adoption and Diffusion of Transcarotid Artery Revascularization in Contemporary Practice

BACKGROUND

In 2015, the FDA approved transcarotid artery revascularization (TCAR) as an alternative to carotid endarterectomy (CEA) and transfemoral carotid artery stenting (TF-CAS) for high-risk patients with carotid stenosis. This was granted in the absence of level 1 evidence to support TCAR. We aimed to document trends in TCAR utilization, its diffusion over time, and the clinical phenotypes of patients undergoing TCAR, CEA, and TF-CAS.

METHODS

We used the Vascular Quality Initiative to study patients who underwent TCAR. We calculated the number of TCARs performed and the percent of TCAR utilization versus CEA/TF-CAS. Using data from before TCAR was widespread, we calculated propensity scores for patients to receive CEA. We applied this model to patients undergoing carotid revascularization from 2016 to 2022 and grouped patients by the procedure they ultimately underwent, examining overlap in score distribution to measure patient similarity. We measured the trend of in-hospital stroke/death after TCAR.

RESULTS

We studied 31 447 patients who underwent TCAR from January 1, 2016 to March 31, 2022. The number of centers performing TCAR increased from 29 to 606. In 2021, TCAR represented 22.5% of carotid revascularizations at centers offering all 3 procedures. The percentage of patients that underwent TCAR who met approved high-risk criteria decreased from 88.5% to 80.9% (P<0.001). Those with a prior ipsilateral carotid procedure decreased from 20.6% in 2016 to 12.0% in 2021 (P<0.001). Patients undergoing TCAR after stroke increased from 19.7% to 30.7% (P<0.001). Propensity-score overlap was 55.4% for TCAR/CEA, and 58.6% for TCAR/TF-CAS, demonstrating that TCAR patients have a clinical phenotype mixed between those who undergo CEA and TF-CAS. The average in-hospital stroke/death risk after TCAR was 2.3% in 2016 and 1.7% in 2022 (P trend: 0.954).

CONCLUSIONS

TCAR now represents nearly 1-in-4 procedures at centers offering it. TCAR was increasingly performed among standard-risk patients and as a first-line procedural option after stroke. The absence of level 1 evidence underscores the importance of high-quality registry-based analyses to document TCAR's real-world outcomes and durability.

Interventions in Carotid Artery Surgery: An Overview of Current Management and Future Implications

Atherosclerotic carotid artery disease has been well studied over the last half-century by multiple randomized controlled trials attempting to elucidate the appropriate modality of therapy for this disease process. Surgical techniques have evolved from carotid artery endarterectomy and transfemoral carotid artery stenting to the development of hybrid techniques in transcarotid artery revascularization. In this article, the authors provide a review of the available literature regarding operative and medical management of carotid artery disease.

Fluid-structure interaction study of hemodynamics and its biomechanical influence on carotid artery atherosclerotic plaque deposits

Atherosclerotic plaque deposits are common causes of blood flow disruption in the carotid artery bifurcation and the associated fluid mechanics has been extensively studied using Computational Fluid Dynamics (CFD) and Fluid Structure Interaction (FSI). However, the elastic responses of plaques to hemodynamics in the carotid artery bifurcation has not been deeply studied using either of the above-mentioned numerical techniques. In this study, a two-way FSI study was coupled with CFD technique, using Arbitrary-Lagrangian-Eulerian method, to study the biomechanics of blood flow on nonlinear and hyperelastic calcified plaque deposits in a realistic geometry of the carotid sinus. FSI parameters such as total mesh displacement and von Misses stress on the plaque, as well as flow velocity and blood pressure around the plaques, were analyzed and compared to variables such as velocity streamline, pressure and wall shear stress obtained from CFD simulation in a healthy model. The blood flow simulations reveal complete reversed blood flow behavior in the internal carotid artery, ICAs and external carotid artery, ECAs for both cases. In particular, this study suggests that plaques, irrespective of the masses, possess a high yielding response to hemodynamic forces at the attaching edges, while the surfaces are vulnerable to rupture.

Analysis of the anatomic eligibility for transcarotid artery revascularization in Chinese patients who underwent carotid endarterectomy and transfemoral carotid artery stenting

Objective

Transcarotid artery revascularization (TCAR) is thought to be a promising technique and instrument for treating carotid stenosis with favorable outcomes. Since there remain several differences in anatomic characteristics among races, this study was conducted to investigate the anatomic eligibility of TCAR in Chinese patients who underwent carotid revascularization.

Methods

A retrospective review of patients with carotid stenosis from 2019 to 2021 was conducted. The anatomic eligibility of TCAR was based on the instruction of the ENROUTE Transcarotid Neuroprotection System. The carotid artery characteristics and configuration of the circle of Willis (CoW) were evaluated by CT angiography. The demographic and clinical characteristics and procedure-related complications were recorded. Logistic regression was used to analyze the independent factors for TCAR eligibility.

Results

Of 289 consecutive patients [222 for carotid endarterectomy (CEA) and 67 for transfemoral carotid artery stenting (TF-CAS)] identified, a total of 215 patients (74.4%) met TCAR anatomic eligibility. Specifically, 83.7% had mild common carotid artery (CCA) puncture site plaque, 95.2% had 4-9 mm internal carotid artery diameters, 95.8% had >6 mm CCA diameter, and 98.3% had >5 cm clavicle to carotid bifurcation distance. Those who were female (OR, 5.967; 95% CI: 2.545-13.987; P < 0.001), were of an older age (OR, 1.226; 95% CI: 1.157-1.299; P < 0.001), and higher body mass index (OR, 1.462; 95% CI: 1.260-1.697; P < 0.001) were prone to be associated with TCAR ineligibility. In addition, 71 patients with TCAR eligibility (33.0%) were found to combine with incomplete CoW. A high risk for CEA was found in 29 patients (17.3%) with TCAR eligibility, and a high risk for TF-CAS was noted in nine patients (19.1%) with TCAR eligibility. Overall, cranial nerve injury (CNI) was found in 22 patients after CEA, while 19 of them (11.3%) met TCAR eligibility.

Conclusion

A significant proportion of Chinese patients meet the anatomic criteria of TCAR, making TCAR a feasible treatment option in China. Anatomic and some demographic factors play key roles in TCAR eligibility. Further analysis indicates a potential reduction of procedure-related complications in patients with high-risk carotid stenosis under the TCAR procedure.

Relationship of pharmacotherapy and the incidence of embolic complications of carotid reconstructive surgery

Aim. To evaluate the relationship between lipid-lowering and antiplatelet therapy and the incidence of cerebral microembolism and related complications in open and endovascular revascularization of the carotid arteries (CA).

Material and methods. This single-center study involved patients with internal CA stenosis. The patients were divided into 2 groups depending on the surgery type performed: carotid endarterectomy (CEA)  — 163 patients; CA stenting (CAS)  — 71 patients. All patients underwent intraoperative transcranial Doppler monitoring to register cerebral embolism during CAS and CE.

Results. In CAS, microembolism episodes were observed in 66,2% vs 22,1% of patients in the CEA group (p=0,04), the largest number of which was recorded during catheterization of the internal CA and embolic filter installation (p=0,000). There were no significant differences between the groups in terms of the stroke incidence. In 8 patients in the CAS group and 1 patient in the CEA group, a transient ischemic attack was observed within 30 days after surgery (p=4x10-4 ). Intraoperative embolism was a predictor of a neurological event in the early postoperative period (odds ratio (OR), 33,08; 95% confidence interval (CI): 3,49-56,37 (p6 months before surgery reduces the likelihood of embolism by 4 times (OR 0,25; 95% CI: 0,11-0,58 (p=0,001), while lipid-lowering and antiplatelet therapy combination — by 12,5 times (OR, 0,08; 95% CI: 0,01-0,40 (p=0,001)).

Conclusion. Preoperative antiplatelet and statin therapy reduces the likelihood of embolism during the CA revascularization procedure.

Current evidence for transcarotid artery stenting with flow reversal as the preferred carotid artery stenting approach

Although the transfemoral approach to carotid artery stenting offers a minimally invasive method for treatment of carotid atherosclerotic disease, this technique for carotid revascularization has unfortunately not led to equivalent overall outcomes of stroke or death compared with endarterectomy in symptomatic or high-risk patients. Transcarotid artery revascularization (TCAR) with a flow reversal neuroprotection system was designed to reduce the embolic risk associated with the transfemoral approach, but randomized trials have yet to be published comparing transfemoral carotid artery stenting with TCAR. Regardless, many surgeons and interventionalists have already adopted TCAR as the preferred modality for carotid artery stenting, given the accumulating evidence supporting the reduced stroke or death benefits of TCAR over the transfemoral approach.

Analysis of Medicare Payments and Patient Outcomes With Pre-Operative Imaging for Carotid Endarterectomy

OBJECTIVE

The use of radiographic evaluation of carotid disease may vary, and current guidelines do not strongly recommend the use of cross-sectional imaging (CSI) prior to surgical intervention. We sought to describe the trends in preoperative carotid imaging and evaluate the associated clinical outcomes and Medicare payments for patients undergoing carotid endarterectomy (CEA) for asymptomatic carotid disease.

METHODS

We used a 20% Medicare sample from 2006 to 2014 identifying patients undergoing CEA for asymptomatic disease. We evaluated preoperative carotid ultrasound and CSI use: CT or MRI of the neck prior to CEA. We calculated average payments of each study from the carrier file and revenue center file. Imaging payments included both the professional component (PC) and the technical component (TC). Claims with a reimbursement of $0 and studies where payment for both the TC and PC could not be identified were excluded from the overall calculation to determine average payment per study. Inpatient reimbursements according to DRG 37-39 were calculated. We compared hospital length of stay (LOS), in hospital stroke, carotid re-exploration, and mortality according to CSI use.

RESULTS

A total of 58,993 CEAs were identified with pre-operative carotid imaging. The average age was 74.8 ± 7.5 years, and 56.0% were men. A total of 19,678 (33%) patients had ultrasound alone with an average of (2.4 ± 1.9) exams prior to CEA. A total of 39,315 patients underwent CSI prior to CEA with 2.5 ± 2.1 ultrasounds, 0.95 ± 0.86 neck CTs and 0.47 ± 0.7 MRIs per patient. The average payment for ultrasound was $140 ± 40, $282 ± 94 for CT and $410 ± 146 for MRI. The average inpatient reimbursements were $7,413 ± 4,215 for patients without CSI compared with $7,792 ± 3,921 for patients with CSI, P < 0.001. The average LOS during CEA admission was 2.5 ± 3.7days. Patients with CSI had a slightly lower percentage of patients being discharged by postoperative day 2 compared with ultrasound alone (88.9% vs. 91.5%, respectively, P < 0.001). The overall in-hospital stroke rate was 0.38% and carotid re-exploration rate was 1.0% and there was no statistical significant difference between groups. Median follow-up was 3.9 years, and mortality at 8 years was 50% and did not statistically differ between groups.

CONCLUSIONS

Our analysis found preoperative imaging to include CSI in nearly two-thirds of patients prior to CEA for asymptomatic disease. As imaging and inpatient payments were higher with patients with CSI further work is needed to understand when CSI is appropriate prior to surgical intervention to appropriately allocate healthcare resources.

Outcomes of Carotid Revascularization in the Treatment of Restenosis After Prior Carotid Endarterectomy

BACKGROUND AND PURPOSE

Restenosis after carotid endarterectomy (CEA) is associated with an increased risk of ipsilateral stroke. The optimal procedural modality for this indication has yet to be determined. Here, we evaluate the in-hospital outcomes of transcarotid artery revascularization (TCAR), redo-CEA, and transfemoral carotid artery stenting (TFCAS) in a large contemporary cohort of patients who underwent treatment for restenosis after CEA.

METHODS

We performed a retrospective analysis of all patients in the vascular quality initiative database who underwent TCAR, redo-CEA, or TFCAS after ipsilateral CEA between September 2016 and April 2020. Patients with prior ipsilateral CAS were excluded from this analysis. In-hospital outcomes following TCAR versus CEA and TCAR versus TFCAS were evaluated using multivariate logistic regression analysis.

RESULTS

A total of 4425 patients were available for this analysis. There were 963 (21.8%) redo-CEA, 1786 (40.4%) TFCAS, and 1676 (37.9%) TCAR. TCAR was associated with lower odds of in-hospital stroke/death (odds ratio [OR], 0.41 [95% CI, 0.24-0.70], P=0.021), stroke (OR, 0.46 [95% CI, 0.23-0.93], P=0.03), myocardial infarction (MI; OR, 0.32 [95% CI, 0.14-0.73], P=0.007), stroke/transient ischemic attack (OR, 0.42 [95% CI, 0.24-0.74], P=0.002), and stroke/death/MI (OR, 0.41 [95% CI, 0.24-0.70], P=0.001) when compared with redo-CEA. There was no significant difference in the odds of death between the 2 groups (OR, 0.99 [95% CI, 0.28-3.5], P=0.995). TCAR was also associated with lower odds of stroke/transient ischemic attack (OR, 0.37 [95% CI, 0.18-0.74], P=0.005) when compared with TFCAS. There was no significant difference in the odds of stroke, death, MI, stroke/death, or stroke/death/MI between TCAR and TFCAS.

CONCLUSIONS

TCAR was associated with significantly lower odds of in-hospital stroke, MI, stroke/transient ischemic attack, stroke/death, and stroke/death/MI when compared with redo-CEA and lower odds of in-hospital stroke/transient ischemic attack when compared with TFCAS. Additional long-term studies are warranted to establish the role of TCAR for the treatment of restenosis after CEA.

Assessing the Suitability of the Carotid Bifurcation for Stenting: Anatomic and Morphologic Considerations

OBJECTIVE

Over the years where stents have been used to treat carotid lesions, a great deal has been learned about which anatomical characteristics lead to adverse outcomes. This review summarizes the anatomic and morphologic characteristics of the carotid vasculature that can help guide patient selection and clinical decision-making.

METHODS

Each of the carotid artery anatomy and lesion characteristics that are relevant to carotid stenting are described in detail. These are accompanied with evidence-based outcomes and results.

RESULTS

Data on the prevalence of carotid artery lesions that are unsuitable for stenting are summarized and the implications of these data for practice are discussed, especially as they pertain to transcarotid artery revascularization.

CONCLUSIONS

CAS can be viable option for carotid revascularization, but the lesion must be acceptable and safe for stent placement. There should be thorough assessment to rule out the presence of severe tortuosity, long-segment disease, severe calcification (circumferential or exophytic), mobile-plaque, swollen ICA sign, and carotid diameters outside the acceptable range. In carefully chosen lesions with the absence of the unfavorable characteristics described-TCAR may offer improved periprocedural success, and CAS may attain better long-term durability.

Learning curve and proficiency of transcarotid artery revascularization compared to transfemoral carotid artery stenting

Both transfemoral carotid artery stenting (TF-CAS) and transcarotid artery revascularization (TCAR) are competing endovascular alternatives to carotid endarterectomy for the treatment of atherosclerotic carotid artery stenosis. TF-CAS is an endovascular procedure associated with a long learning curve and higher periprocedural stroke and death rates during an operator's early experience. Estimates suggest that more than 50 cases are required to achieve outcomes similar to carotid endarterectomy. TCAR is a novel hybrid procedure combining direct common carotid artery access and cerebral blood flow reversal with carotid stent placement. In distinction from TF-CAS, TCAR has a rather short learning curve. A multi-institutional analysis showed that operators achieved technical proficiency after approximately 10 to 15 cases. This was reinforced by a large Society for Vascular Surgery, Vascular Quality Initiative Transcarotid Artery Revascularization Surveillance Project analysis that demonstrated that expertise peaked after approximately 20 cases. Both studies found that TCAR was not associated with an increased rate of stroke or death during operator's early experience. These data suggest that TCAR is readily learned and patients are not at increased risk during a surgeon's early experience.

Is it possible to prevent cerebral embolization by improving the design and technology of carotid stent implantation?

INTRODUCTION

The prevention of atherosclerotic plaque fragmentation during carotid artery stenting is a fundamental problem in decreasing the risk of disability of patients. The goal of this review is to clarify whether the stent design can have a decisive impact on the rate of intraoperative and postoperative complications.

AREAS COVERED

Different designs of the carotid stents are briefed and the advantages and disadvantages of different stent designs are discussed as well as the results of their clinical use. Various solutions are presented to reduce cerebral embolism during carotid artery stenting.

EXPERT OPINION

There is no conclusive evidence for the benefits of closed cell and hybrid stents. The stent design cannot completely resolve the problem of cerebral embolism. Most of the events of cerebral microembolism occur at the stages of stent delivery rather than protrusion of an atherosclerotic plaque in the long-term follow-up. Most likely, minimization of the risks for periprocedural and postprocedural strokes requires not only the new solutions in stent design as well as the corresponding delivery systems and brain embolic protection systems, but also the new strategies of preprocedural drug stabilization of the atherosclerotic plaque in the carotid artery. Abbreviations: CAS, carotid artery stenting; CE, carotid endarterectomy; DW-MRI, diffusion-weighted magnetic resonance imaging; ECA, external carotid artery; ICA, internal carotid artery; IVUS, intravascular ultrasound examination; OCT, optical coherence tomography.

Critical Appraisal on the Quality of Reporting on Safety and Efficacy of Transcarotid Artery Stenting With Flow Reversal

Transcarotid revascularization is an alternative to transfemoral carotid artery stenting, designed to avoid aortic arch manipulation and concomitant periprocedural stroke. This article aims to perform a detailed analysis on the quality of the currently available evidence on safety and efficacy of transcarotid artery revascularization. Although current evidence is promising, independent randomized controlled studies comparing transcarotid artery revascularization with carotid endarterectomy in recently symptomatic patients are lacking and will be necessary to establish the true value of transcarotid artery revascularization in carotid artery revascularization.