The Efficacy of Transcarotid Artery Revascularization With Flow Reversal System Compared to Carotid Endarterectomy: A Systematic Review and Meta-Analysis

An International, Expert-Based Delphi Consensus Document on Controversial Issues about TransCarotid Artery Revascularization (TCAR)

BACKGROUND

Transcarotid artery revascularization (TCAR) has emerged as an alternative therapeutic modality to carotid endarterectomy (CEA) and transfemoral carotid artery stenting (TFCAS) for the management of patients with carotid artery stenosis. However, certain issues regarding the indications and contraindications of TCAR remain unanswered or unresolved. The aim of this international, expert-based Delphi consensus document was to attempt to provide some guidance on these topics.

METHODS

A 3-round Delphi consensus process was performed, including 29 experts. The aim of round 1 was to investigate the differing views and opinions of the participants. Round 2 was carried out after the results from the literature on each topic were provided to the participants. During round 3, the participants had the opportunity to finalize their vote.

RESULTS

Most participants agreed that TCAR can or can probably or possibly be performed within 14 days of a cerebrovascular event, but it is best to avoid it in the first 48 hr. It was felt that TCAR cannot or should not replace TFCAS or CEA, as each procedure has specific indications and contraindications. Symptomatic patients >80 years should probably be treated with TCAR rather than with TFCAS. TCAR can or can probably be used for the treatment of restenosis following CEA or TFCAS. Finally, there is a need for a randomized controlled trial (RCT) to provide better evidence for the unresolved issues.

CONCLUSIONS

This Delphi consensus document attempted to assist the decision-making of physicians or interventionalists or vascular surgeons involved in the management of carotid stenosis patients. Furthermore, areas requiring additional research were identified. Future studies and RCTs should provide more evidence to address the unanswered questions regarding TCAR.

Symptomatic Cervical Carotid Artery Stenosis: Evolving Paradigms in Risk Stratification and Intervention

Symptomatic carotid disease, characterized by atherosclerotic or non-atherosclerotic internal carotid artery disease with ipsilateral stroke symptoms, represents a critical condition in stroke neurology. This "hot carotid" state carries a high risk of stroke recurrence, with almost one-fourth of the patients experiencing recurrent ischemic events within 2 weeks of initial presentation. The global prevalence of significant carotid stenosis (conventionally defined as ≥50% narrowing) is estimated at around 1.8% in men and 1.2% in women and increases with age. Management of symptomatic carotid disease remains challenging, requiring a balance between urgent medical and surgical interventions and their associated risks. Current treatment approaches combine medical management, focusing on optimal antithrombotic therapy, with revascularization procedures such as carotid endarterectomy or carotid artery stenting. However, decision making has evolved beyond considering stenosis degree alone, now incorporating advanced imaging data on plaque composition and intraluminal characteristics. Even though there are numerous randomized trials, uncertainties persist regarding optimal management, particularly in light of improved medical therapies and emerging concepts like symptomatic non-stenotic carotid disease. Future research directions include exploring newer antithrombotic regimens, refining patient selection criteria for revascularization, and evaluating novel techniques like transcarotid artery revascularization.

Postoperative outcomes in patients with anemia undergoing carotid revascularization

BACKGROUND

Preoperative anemia is associated with worse postoperative morbidity and mortality after major vascular procedures. Limited research has examined the optimal method of carotid revascularization in patients with anemia. Therefore, we aim to compare the postoperative outcomes after carotid endarterectomy (CEA), transfemoral carotid artery stenting (TFCAS), and transcarotid artery revascularization (TCAR) among patients with anemia.

STUDY DESIGN

This is a retrospective review of patients with anemia undergoing CEA, TFCAS, and TCAR in the Vascular Quality Initiative database between 2016 and 2023. We defined anemia as a preoperative hemoglobin level of <13 g/dL in men and <12 g/dL in women. The primary outcomes were 30-day mortality and in-hospital major adverse cardiac events (MACE). Logistic regression models were used for multivariate analyses.

RESULTS

Our study included 40,383 CEA (59.3%), 9159 TFCAS (13.5%), and 18,555 TCAR (27.3%) cases in patients with anemia. TCAR patients were older and had more medical comorbidities than CEA and TFCAS patients. TCAR was associated with a decreased 30-day mortality (adjusted odds ratio [aOR], 0.45; 95% confidence interval [CI], 0.37-0.59; P < .001), in-hospital MACE (aOR, 0.58; 95% CI, 0.46-0.75; P < .001) compared with TFCAS. Additionally, TCAR was associated with a 20% decrease in the risk of 30-day mortality (aOR, 0.80; 95% CI, 0.65-0.98; P = .03) and a similar risk of in-hospital MACE (aOR, 0.86; 95% CI, 0.77-1.01; P = .07) compared with CEA. Furthermore, TFCAS was associated with an increased risk of 30-day mortality (aOR, 2; 95% CI, 1.5-2.68; P < .001) and in-hospital MACE (aOR, 1.7; 95% CI, 1.4-2; P < .001) compared with CEA.

CONCLUSIONS

In this multi-institutional national retrospective analysis of a prospectively collected database, TFCAS was associated with a high risk of 30-day mortality and in-hospital MACE compared with CEA and TCAR in patients with anemia. TCAR was associated with a lower risk of 30-day mortality compared with CEA. These findings suggest TCAR as the optimal minimally invasive procedure for carotid revascularization in patients with anemia.

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.

The intracranial effects of flow reversal during transcarotid artery revascularization

Background

This study aimed to assess intraoperative cerebral hemodynamic responses and embolic events during transcarotid artery revascularization via transcranial Doppler, near-infrared spectroscopy, and bispectral index monitoring.

Methods

Twelve patients (7 males, 5 females; mean age: 72.8±9.0 years; range, 63 to 91 years) undergoing transcarotid artery revascularization with simultaneous transcranial Doppler, near-infrared spectroscopy, and bispectral index monitoring were analyzed in this retrospective study between September 2017 and December 2019. The mean flow velocity and pulsatility index of the middle cerebral artery, alongside near-infrared spectroscopy and bispectral index values, before flow reversal, during flow reversal, and after flow reversal phases were investigated. The presence and frequency of high-intensity transient signals were recorded to evaluate embolic incidents.

Results

Significant reductions in middle cerebral artery mean flow velocity were noted during flow reversal (40.58±10.57 cm/sec to 20.58±14.34 cm/sec, p=0.0004), which subsequently returned to and exceeded baseline values after flow reversal cessation (53.33±17.69 cm/sec, p=0.0005). Near-infrared spectroscopy (71±4.4% to 66±6.2%) and bispectral index (45.71±8.5 to 40.14±8.1) values mirrored these hemodynamic changes, with notable decreases during flow reversal, and recoveries after flow reversal. The highest concentration of high-intensity transient signals was observed during stent deployment, signifying a critical embolic phase. No perioperative neurological complications or other significant adverse events were documented.

Conclusion

Transcranial Doppler, near-infrared spectroscopy, and bispectral index effectively monitor cerebral hemodynamics and embolic potential during transcarotid artery revascularization, providing real-time data crucial for optimizing perioperative management. These findings underscore the clinical value of multimodal monitoring in improving patient outcomes in transcarotid artery revascularization procedures.

Trans-Carotid Artery Revascularization Versus Carotid Endarterectomy in Patients With Carotid Artery Disease: Systematic Review and Meta-analysis of 30-day Outcomes

This systematic review and meta-analysis compared trans-carotid artery revascularization (TCAR) as an alternative approach to carotid endarterectomy (CEA) in patients with carotid artery disease. An electronic search was conducted using PubMed, Scopus, and Cochrane databases including comparative studies with patients who underwent either TCAR or CEA. This meta-analysis is according to the recommendations of the PRISMA statement. Eight studies met our eligibility criteria, incorporating 7,606 and 7,048 patients in the TCAR and CEA groups, respectively. Thirty-day mortality (odds ratio [OR]: 0.94, 95% confidence interval [CI]: 0.56-1.56, P = .81) and stroke (OR: 0.92, 95%CI 0.70-1.22, P = .57) were similar between the two groups, with low heterogeneity. The odds of myocardial infarction (OR: 1.79, 95% CI: 1.18-2.71, P = .01) and cranial nerve injury were significantly higher in patients undergoing CEA compared with TCAR (OR: 4.11, 95% CI: 2.59-6.51, P < .001). The subgroup analysis according to symptomatic pre-intervention status revealed no statistically significant difference regarding 30-day mortality (symptomatic OR: 0.91, 95% CI: 0.40-2.07, P = .82, asymptomatic OR: 0.93, 95% CI: 0.46-1.86, P = .83) and stroke (symptomatic OR: 0.88, 95% CI:0.47-1.64, P = .68, asymptomatic OR: 0.93, 95% CI: 0.64-1.35, P = .70). TCAR offers an alternative treatment for patients with carotid artery stenosis with comparable to CEA mortality and stroke rates during a 30-day post-operative period.

Propensity-Score Matched Analysis of Three Years Survival of Trans Carotid Artery Revascularization Versus Carotid Endarterectomy in the Vascular Quality Initiative Medicare-Linked Database

OBJECTIVE

Carotid endarterectomy (CEA) remains the gold standard procedure for carotid revascularization. Transfemoral carotid artery stenting (TFCAS) was introduced as a minimally invasive alternative procedure in patients who are at high risk for surgery. However, TFCAS was associated with an increased risk of stroke and death compared to CEA.

BACKGROUND

Transcarotid artery revascularization (TCAR) has outperformed TFCAS in several prior studies and has shown similar perioperative and 1-year outcomes compared with CEA. We aimed to compare the 1-year and 3-year outcomes of TCAR versus CEA in the Vascular Quality Initiative (VQI)-Medicare-Linked [Vascular Implant Surveillance and Interventional Outcomes Network (VISION)] database.

METHODS

The VISION database was queried for all patients undergoing CEA and TCAR between September 2016 to December 2019. The primary outcome was 1-year and 3-year survival. One-to-one propensity-score matching (PSM) without replacement was used to produce 2 well-matched cohorts. Kaplan-Meier estimates, and Cox regression was used for analyses. Exploratory analyses compared stroke rates using claims-based algorithms for comparison.

RESULTS

A total of 43,714 patients underwent CEA and 8089 patients underwent TCAR during the study period. Patients in the TCAR cohort were older and were more likely to have severe comorbidities. PSM produced two well-matched cohorts of 7351 pairs of TCAR and CEA. In the matched cohorts, there were no differences in 1-year death [hazard ratio (HR)=1.13; 95% CI, 0.99-1.30; P =0.065]. At 3-years, TCAR was associated with slight increased risk of death (HR=1.16; 95% CI, 1.04-1.30; P =0.008). When stratifying by initial symptomatic presentation, the increased 3-year death associated with TCAR persisted only in symptomatic patients (HR=1.33; 95% CI, 1.08-1.63; P =0.008). Exploratory analyses of postoperative stroke rates using administrative sources suggested that validated measures of claims-based stroke ascertainment are necessary.

CONCLUSIONS

In this large multi-institutional PSM analysis with robust Medicare-linked follow-up for survival analysis, the rate of death at 1 year was similar in TCAR and CEA regardless of symptomatic status. The slight increase in the risk of 3-year death in symptomatic patients undergoing TCAR is likely confounded by more severe comorbidities despite matching. A randomized controlled trial comparing TCAR to CEA is necessary to further determine the role of TCAR in standard-risk patients requiring carotid revascularization.

Predictors of 30-Day Stroke and Death After Transcarotid Revascularization

INTRODUCTION

Much of the previous robust analyses of the results associated with transcarotid revascularization (TCAR) derives from industry-sponsored trials or the Vascular Quality Initiative (VQI). This investigation was performed to identify preoperative predictors of 30-day stroke and death using institutional databases.

METHODS

A retrospective analysis was performed of carotid revascularization databases created at two high-volume TCAR centers and maintained independently of the VQI carotid module between December 2015 and December 2021. The primary outcome of interest was a composite of perioperative (30-day) stroke and death. Univariate regression analyses, followed by multivariate regression analyses, were performed to identify potential predictors of adverse events.

RESULTS

During the study period, 750 TCAR procedures were performed at our combined health systems, resulting in 24 (3.2%) individuals who experienced either stroke and/or death in the perioperative period. Of these, we observed nine (1.2%) mortality events and 18 (2.4%) strokes. On univariate analysis, candidate protectors of stroke/death were found to be coronary artery disease (odds ratio [OR], 0.43; 95% confidence interval [CI], 0.18-1.01; P = 0.05) and protamine reversal (0.51; 0.21-1.21; P = 0.15). Candidate predictors of the primary outcome were anticoagulant usage (3.03; 1.26-7.24; P = 0.01), postprocedural debris in the filter (2.30; 0.97-5.43; P = 0.06), symptomatic carotid lesion (2.03; 0.90-4.50), and cardiac arrhythmia (1.98; 0.80-4.03; P = 0.14). On multivariate analysis, two predictors remained, cardiac arrhythmia (4.21; 1.10-16.16; P = 0.04) and symptomatic carotid lesion (14.49; 1.80-116.94; P = 0.01).

CONCLUSIONS

A symptomatic carotid lesion, and to a lesser extent cardiac arrhythmia, are strong predictors of 30-day stroke/death after TCAR. Surgeons should be cognizant of the increased risk of adverse events in the perioperative period in these patients.

Update on Management of Symptomatic Carotid Stenosis

Carotid artery stenosis (CAS) is one of the leading causes of cerebral ischemia and stroke.7 When plaque builds up in the internal carotid artery, it blocks blood flow to the brain. Oftentimes, this condition only comes to light after a patient experiences a stroke or stroke-like symptoms. When this occurs, cholesterol-lowering medications and blood thinners can help to increase blood flow to the brain. However, if the plaque is so large that it severely narrows the lumen of the artery, surgery may be required to restore blood flow to the brain. Patients with severe stenosis can undergo procedures such as carotid endarterectomies (CEA), stenting, and transcarotid artery revascularization (TCAR) for this purpose. In this review, we discuss these procedures and which patients warrant which type of intervention. We look at the pathophysiology of internal carotid artery stenosis and current treatment options, while highlighting emerging treatment options. This review aims to increase understanding of the management of symptomatic carotid artery stenosis as well as provide a groundwork for more innovative treatments.