Association of Adoption of Transcarotid Artery Revascularization With Center-Level Perioperative Outcomes

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.

Racial differences in adoption and outcomes of transcarotid artery revascularization among high-risk adults with carotid artery stenosis

INTRODUCTION

Differential access to new technologies may contribute to racial disparities in surgical outcomes but has not been well-studied in the treatment of carotid artery stenosis. We examined race-based differences in adoption and outcomes of transcarotid artery revascularization (TCAR) among high-risk non-Hispanic (NH) NH Black and NH white adults undergoing carotid revascularization.

METHODS

We conducted a retrospective analysis of TCAR, transfemoral carotid artery stenting (TF-CAS), and carotid endarterectomy (CEA) procedures performed for carotid artery stenosis from 1/2015 to 7/2023 in the Vascular Quality Initiative. NH Black and NH white adults were included if they met Centers for Medicare & Medicaid Services high-risk criteria. Hospitals and physicians were categorized as TCAR-capable if they had previously performed at least one TCAR prior to the time of a given procedure. We fit logistic and linear regressions, adjusted a priori for common demographic, clinical, and disease characteristics, to estimate associations of race with receipt of TCAR (versus CEA or TF-CAS), and to explore associations between race, hospital and physician characteristics, and perioperative composite stroke/death/myocardial infarction.

RESULTS

Of 159,471 high-risk patients undergoing revascularization for carotid artery stenosis (mean age 72 years, 38.5% female, 5.3% NH Black), 28,722 (18.0%) received TCAR, including 16.9% of NH Black adults and 18.1% of NH white adults (P<0.001). After controlling for patient and disease characteristics, NH Black patients were less likely than NH white patients to receive TCAR (aOR 0.92, 95% CI 0.87 to 0.99). The use of TCAR did not vary by race among patients treated at TCAR-capable hospitals (aOR 0.98, 95% CI 0.91 to 1.05) or by TCAR-capable physicians (aOR 1.01, 95% CI 0.93 to 1.10); however, NH Black race was associated with lower odds of receiving treatment in these settings (TCAR-capable hospital: aOR 0.93 [0.88 to 0.98]; TCAR-capable physician: aOR 0.92 [0.87 to 0.98]). NH Black race was associated with higher odds of stroke/death/MI in the full cohort (aOR 1.18, 95% CI 1.03 to 1.36), but not in the subgroup of patients who received TCAR (aOR 0.87, 95% CI 0.56 to 1.34).

CONCLUSIONS

TCAR attenuated racial disparities in perioperative morbidity and mortality associated with carotid revascularization, but NH Black adults were less likely than NH white adults to receive TCAR. Relatively worse access for NH Black adults to technologically-advanced treatment settings may partially explain the broader persistence of race-based differences in carotid revascularization treatment patterns and outcomes.

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 (MACEs). 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 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 is 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.

Carotid revascularisation versus medical treatment for asymptomatic carotid artery stenosis

OBJECTIVES

This is a protocol for a Cochrane Review (intervention). The objectives are as follows: To compare the safety and efficacy of carotid revascularisation plus best medical treatment with best medical treatment alone in people with asymptomatic carotid artery stenosis.

Patient decision-making in the era of transcarotid artery revascularization

OBJECTIVE

The National Coverage Determination on carotid stenting by Medicare in October 2023 stipulates that patients participate in a shared decision-making (SDM) conversation with their proceduralist before an intervention. However, to date, there is no validated SDM tool that incorporates transcarotid artery revascularization (TCAR) into its decision platform. Our objective was to elicit patient and surgeon experiences and preferences through a qualitative approach to better inform the SDM process surrounding carotid revascularization.

METHODS

We performed longitudinal perioperative semistructured interviews of 20 participants using purposive maximum variation sampling, a qualitative technique designed for identification and selection of information-rich cases, to define domains important to participants undergoing carotid endarterectomy or TCAR and impressions of SDM. We also performed interviews with nine vascular surgeons to elicit their input on the SDM process surrounding carotid revascularization. Interview data were coded and analyzed using inductive content analysis coding.

RESULTS

We identified three important domains that contribute to the participants' ultimate decision on which procedure to choose: their individual values, their understanding of the disease and each procedure, and how they prefer to make medical decisions. Participant values included themes such as success rates, "wanting to feel better," and the proceduralist's experience. Participants varied in their desired degree of understanding of carotid disease, but all individuals wished to discuss each option with their proceduralist. Participants' desired medical decision-making style varied on a spectrum from complete autonomy to wanting the proceduralist to make the decision for them. Participants who preferred carotid endarterectomy felt outcomes were superior to TCAR and often expressed a desire to eliminate the carotid plaque. Those selecting TCAR felt it was a newer, less invasive option with the shortest procedural and recovery times. Surgeons frequently noted patient factors such as age and anatomy, as well as the availability of long-term data, as reasons to preferentially select one procedure. For most participants, their surgeon was viewed as the most important source of information surrounding their disease and procedure.

CONCLUSIONS

SDM surrounding carotid revascularization is nuanced and marked by variation in patient preferences surrounding autonomy when choosing treatment. Given the mandate by Medicare to participate in a SDM interaction before carotid stenting, this analysis offers critical insights that can help to guide an efficient and effective dialog between patients and providers to arrive at a shared decision surrounding therapeutic intervention for patients with carotid disease.

Higher stroke risk after carotid endarterectomy and transcarotid artery revascularization is associated with relative surgeon volume ratio

OBJECTIVE

Adoption of transcarotid artery revascularization (TCAR) by surgeons has been variable, with some still performing traditional carotid endarterectomy (CEA), whereas others have shifted to mostly TCAR. Our goal was to evaluate the association of relative surgeon volume of CEA to TCAR with perioperative outcomes.

METHODS

The Vascular Quality Initiative CEA and carotid artery stent registries were analyzed from 2021 to 2023 for symptomatic and asymptomatic interventions. Surgeons participating in both registries were categorized in the following CEA to CEA+TCAR volume percentage ratios: 0.25 (majority TCAR), 0.26 to 0.50 (more TCAR), 0.51 to 0.75 (more CEA), and 0.76 to 1.00 (majority CEA). Primary outcomes were rates of perioperative ipsilateral stroke, death, cranial nerve injury, and return to the operating room for bleeding.

RESULTS

There were 50,189 patients who underwent primary carotid revascularization (64.3% CEA and 35.7% TCAR). CEA patients were younger (71.1 vs 73.5 years, P < .001), with more symptomatic cases, less coronary artery disease, diabetes, and lower antiplatelet and statin use (all P < .001). TCAR patients had lower rates of smoking, obesity, and dialysis or renal transplant (all P < .001). Postoperative stroke after CEA was significantly impacted by the operator CEA to TCAR volume ratio (P = .04), with surgeons who perform majority TCAR and more TCAR having higher postoperative ipsilateral stroke (majority TCAR odds ratio [OR]: 2.15, 95% confidence interval [CI]: 1.16-3.96, P = .01; more TCAR OR: 1.42, 95% CI: 1.02-1.96, P = .04), as compared with those who perform majority CEA. Similarly, postoperative stroke after TCAR was significantly impacted by the CEA to TCAR volume ratio (P = .02), with surgeons who perform majority CEA and more CEA having higher stroke (majority CEA OR: 1.51, 95% CI: 1.00-2.27, P = .05; more CEA OR: 1.50, 95% CI: 1.14-2.00, P = .004), as compared with those who perform majority TCAR. There was no association between surgeon ratio and perioperative death, cranial nerve injury, and return to the operating room for bleeding for either procedure.

CONCLUSIONS

The relative surgeon CEA to TCAR ratio is significantly associated with perioperative stroke rate. Surgeons who perform a majority of one procedure have a higher stroke rate in the other. Surgeons offering both operations should maintain a balanced practice and have a low threshold to collaborate as needed.

Appropriateness of care: Asymptomatic carotid stenosis including transcarotid artery revascularization

Carotid artery stenosis is one of the most common diagnoses treated by vascular specialists in the United States. The optimal management of carotid stenosis remains controversial, however, with notable variation surrounding diagnostic imaging modalities, longitudinal surveillance, medical therapies, and procedural interventions. Data from high-quality randomized controlled trials and observational studies form the foundation for current management paradigms and societal guidelines that inform clinical practice. Presently, a diagnosis of carotid disease is most often established with duplex ultrasound and supplemental cross-sectional imaging using computed tomography or magnetic resonance angiography as needed to provide additional anatomic information. All patients with documented occlusive disease should receive goal-directed medical therapy with antiplatelet agents and a lipid-reduction strategy, most commonly with a statin. Those with severe carotid stenosis and an acceptable life expectancy may be considered for carotid artery revascularization. The proceduralist should optimally consider a shared decision-making approach in which the tradeoffs of revascularization can be carefully considered with the patient to optimize informed therapeutic decision making. In current practice, three distinct procedure options exist to treat carotid artery stenosis, including carotid endarterectomy, transfemoral carotid artery stenting, and transcarotid artery revascularization. It should be noted that each procedure, although often used interchangeably in most clinical settings, carry technical nuances and outcome disparities. In this review, each of these topics are explored and various approaches are outlined surrounding the appropriate use of treatments for patients with asymptomatic carotid artery 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.

Association of stroke or death with severity of carotid lesion calcification in patients undergoing carotid artery stenting

OBJECTIVE

Carotid artery stenting (CAS) for heavily calcified lesions is controversial due to concern for stent failure and increased perioperative stroke risk. However, the degree to which calcification affects outcomes is poorly understood, particularly in transcarotid artery revascularization (TCAR). With the precipitous increase in TCAR use and its expansion to standard surgical-risk patients, we aimed to determine the impact of lesion calcification on CAS outcomes to ensure its safe and appropriate use.

METHODS

We identified patients in the Vascular Quality Initiative who underwent first-time transfemoral CAS (tfCAS) and TCAR between 2016 and 2021. Patients were stratified into groups based on degree of lesion calcification: no calcification, 1% to 50% calcification, 51% to 99% calcification, and 100% circumferential calcification or intraluminal protrusion. Outcomes included in-hospital and 1-year composite stroke/death, as well as individual stroke, death, and myocardial infarction outcomes. Logistic regression was used to evaluate associations between degree of calcification and these outcomes.

RESULTS

Among 21,860 patients undergoing CAS, 28% patients had no calcification, 34% had 1% to 50% calcification, 35% had 51% to 99% calcification, and 3% had 100% circumferential calcification/protrusion. Patients with 51% to 99% and circumferential calcification/protrusion had higher odds of in-hospital stroke/death (odds ratio [OR], 1.3; 95% confidence interval [CI], 1.02-1.6; P = .034; OR, 1.9; 95% CI, 1.1-2.9; P = .004, respectively) compared with those with no calcification. Circumferential calcification was also associated with increased risk for in-hospital myocardial infarction (OR, 3.5; 95% CI, 1.5-8.0; P = .003). In tfCAS patients, only circumferential calcification/protrusion was associated with higher in-hospital stroke/death odds (OR, 2.0; 95% CI, 1.2-3.4; P = .013), whereas for TCAR patients, 51% to 99% calcification was associated with increased odds of in-hospital stroke/death (OR, 1.5; 95% CI, 1.1-2.2; P = .025). At 1 year, circumferential calcification/protrusion was associated with higher odds of ipsilateral stroke/death (12.4% vs 6.6%; hazard ratio, 1.64; P = .002).

CONCLUSIONS

Among patients undergoing CAS, there is an increased risk of in-hospital stroke/death for lesions with >50% calcification or circumferential/protruding plaques. Increasing severity of carotid lesion calcification is a significant risk factor for stroke/death in patients undergoing CAS, regardless of approach.

Risk Factors for Cerebral Hyperperfusion Syndrome following Carotid Revascularization

BACKGROUND

Cerebral hyperperfusion syndrome (CHS) is a rare but known complication of carotid revascularization that can result in severe postoperative disability and death. CHS is a well-described sequela of carotid endarterectomy (CEA) and, more recently, of transfemoral carotid artery stenting (TFCAS), but its incidence after transcarotid artery revascularization (TCAR) has not been delineated. The aims of this study were to determine the impact of procedure type (CEA versus TCAR versus TFCAS) on the development of CHS as well as to identify perioperative risk factors associated with CHS.

METHODS

The Society for Vascular Surgery Vascular Quality Initiative was queried for patients aged ≥18 years who underwent CEA, TCAR, or TFCAS from 2015-2021. Emergent procedures were excluded. The primary outcome was postoperative development of CHS, defined as the presence of postoperative seizures, intracerebral hemorrhage due to hyperperfusion, or both. Bivariate and multivariable logistic regression analyses were performed to identify factors associated with CHS.

RESULTS

156,003 procedures were included (72.7% CEA, 12.4% TCAR, and 14.9% TFCAS). The incidence of CHS after CEA, TCAR, and TFCAS were 0.15%, 0.18%, and 0.53%, respectively. There was no significant difference in risk of CHS after TFCAS compared to CEA (odds ratio [OR]: 1.21; 95% confidence interval [CI] 0.76-1.92; P = 0.416), nor was there a difference between TCAR and CEA (OR: 0.91; 95% CI 0.57-1.45; P = 0.691). Perioperative risk factors associated with an increased risk of CHS included previous history of transient ischemic attack or stroke (OR: 2.50; 95% CI 1.69-3.68; P < 0.0001), necessity for urgent intervention within 48 hr (OR: 2.03; 95% CI 1.43-2.89; P < 0.0001), treatment of a total occlusion (OR: 3.80; 95% CI 1.16-12.47; P = 0.028), and need for postoperative intravenous blood pressure medication (OR: 5.45; 95% CI 3.97-7.48; P < 0.0001). Age, preoperative hypertension, degree of ipsilateral stenosis less than or equal to 99%, and history of prior carotid procedures were not statistically associated with an increased risk of CHS. Discharging patients on an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker was associated with a decreased risk of developing CHS (OR: 0.47; 95% CI 0.34-0.65; P < 0.0001).

CONCLUSIONS

Compared with CEA, TCAR and TFCAS were not statistically associated with an increased risk of postoperative CHS. Patients with a previous history of transient ischemic attack or stroke, who require urgent intervention or postoperative intravenous blood pressure medication, or who are treated for a total occlusion are at a higher risk of developing CHS. Using an angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker on discharge appears to be protective against CHS and should be considered for the highest risk patients.

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.

What Is the Role of Transcarotid Artery Revascularization in the Treatment of Carotid Stenosis?

TCAR for the Treatment of Carotid StenosisTwo carotid revascularization strategies, CEA and TF-CAS, have been informed by high-quality randomized trials. In contrast, no randomized trial evidence exists regarding a newer procedural option, TCAR. The authors discuss these procedures and propose a randomized trial to inform the role of TCAR in the treatment of carotid stenosis.

Proximal versus distal protection: dissecting clinical trials

Carotid artery stenting (CAS) is a valid alternative to conventional carotid endarterectomy for treatment of carotid artery stenosis. Distal embolization of atherosclerotic debris causing cerebrovascular accidents during CAS has been the most significant concern limiting widespread application of CAS technology. A variety of embolic protection devices (EPDs) with different mechanism of action, have been designed to minimize the risk of major embolization causing stroke and their use is recommended by current guidelines. Two general types of EPDs are available: proximal protection devices (PPDs) and distal protection devices (DPDs). However, there is no convincing clinical evidence of the clinical superiority of one device over another. This review will examine the different types of available devices and also innovative devices and techniques, including strengths and weaknesses of each, and present the available evidence and rationale for their routine use during CAS.

Learning the Treatment Impact on Time-to-Event Outcomes: The Transcarotid Artery Revascularization Simulated Cohort

Proportional hazard Cox regression models are overwhelmingly used for analyzing time-dependent outcomes. Despite their associated hazard ratio is a valuable index for the difference between populations, its strong dependency on the underlying assumptions makes it a source of misinterpretation. Recently, a number of works have dealt with the subtleties and limitations of this interpretation. Besides, a number of alternative indices and different Cox-type models have been proposed. In this work, we use synthetic data, motivated by a real-world problem, for showing the strengths and weaknesses of some of those methods in the analysis of time-dependent outcomes. We use the power of synthetic data for considering observable results but also utopian designs.

Procedural Safety Comparison Between Transcarotid Artery Revascularization, Carotid Endarterectomy, and Carotid Stenting: Perioperative and 1-Year Rates of Stroke or Death

Background Transcarotid artery revascularization (TCAR) was approved by the Food and Drug Administration in 2015 for patients with carotid artery stenosis. However, no randomized trial to evaluate TCAR has been performed to date, and previous reports have important limitations. Accordingly, we measured stroke or death after TCAR compared with carotid endarterectomy (CEA) and transfemoral carotid artery stenting (TF-CAS). Methods and Results We used the Vascular Quality Initiative registry to study patients who underwent TCAR, CEA, or TF-CAS from September 2016 to June 2021. Our primary outcomes were perioperative and 1-year stroke or death. We used logistic regression for risk adjustment for perioperative outcomes and Cox regression for risk adjustment for 1-year outcomes. We used a 2-stage residual inclusion instrumental variable (IV) method to adjust for selection bias and other unmeasured confounding. Our instrument was a center's preference to perform TCAR versus CEA or TF-CAS. We performed a subgroup analysis stratified by presenting neurologic symptoms. We studied 21 234 patients who underwent TCAR, 82 737 who underwent CEA, and 14 595 who underwent TF-CAS across 662 centers. The perioperative rate of stroke or death was 2.0% for TCAR, 1.7% for CEA, and 3.7% for TF-CAS (P<0.001). Compared with TCAR, the IV-adjusted odds ratio of perioperative stroke or death for CEA was 0.74 (95% CI, 0.55-0.99) and for TF-CAS was 1.66 (95% CI, 0.99-2.79). Results were similar among both symptomatic and asymptomatic patients. The 1-year rate of stroke or death was 6.4% for TCAR, 5.2% for CEA, and 9.7% for TF-CAS (P<0.001). Compared with TCAR, the IV-adjusted hazard ratio of 1 year stroke or death for CEA was 0.97 (95% CI, 0.80-1.17), and for TF-CAS was 1.45 (95% CI, 1.04-2.02). IV analysis further demonstrated that symptomatic patients with carotid stenosis had the lowest 1-year likelihood of stroke or death with TCAR (compared with TCAR, symptomatic IV-adjusted hazard ratio for CEA: 1.30 [95% CI, 1.04-1.64], and TF-CAS: 1.86 [95% CI, 1.27-2.71]). Conclusions Perioperative stroke or death was greater following TCAR when compared with CEA. However, at 1 year there was no statistically significant difference in stroke or death between the 2 procedures. TCAR performed favorably compared with TF-CAS at both time points. Although CEA remains the gold standard procedure for patients with carotid stenosis, TCAR appears to be a safe alternative to CEA and TF-CAS when used selectively and may be useful when treating symptomatic patients.

Use of Transcarotid Artery Revascularization, Transfemoral Carotid Artery Stenting, and Carotid Endarterectomy in the US From 2015 to 2019

IMPORTANCE

A transcarotid artery revascularization (TCAR) device was approved by the US Food and Drug Administration in 2015 for carotid revascularization in patients at high risk for stroke, cranial nerve injury, or major cardiac event. It is unclear how the introduction of TCAR has changed the use of carotid endarterectomy (CEA) and transfemoral carotid artery stenting (TFCAS).

OBJECTIVE

To quantify the temporal changes in the operative approach to carotid revascularization (CEA vs TFCAS vs TCAR), and to identify patient and disease characteristics commonly associated with each approach.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study obtained data from the Vascular Quality Initiative database from January 1, 2015, to December 31, 2019. Patients with carotid artery stenosis who underwent CEA, TFCAS, or TCAR were included. Data were analyzed from January to April 2022.

EXPOSURES

Month and year of surgery as well as patient risk status.

MAIN OUTCOMES AND MEASURES

Number and proportion of carotid revascularization procedures by operative approach.

RESULTS

A total of 108 676 patients (mean [SD] age 56.6 [12.5] years; 66 684 men [61.4%]) were included in the analysis. The most common operative approach overall was CEA (n = 81 508 [75.0%]), followed by TFCAS (n = 15 578 [14.3%]) and TCAR (n = 11 590 [10.7%]). The number of procedures increased over the study period (16 754 in 2015 vs 27 269 in 2019; P < .001). In 2015, CEA was used in 84.9% of all cases, followed by TFCAS (14.4%) and TCAR (0.8%). In 2019, CEA was used in 64.8% of cases, followed by TCAR (21.9%) and TFCAS (13.3%). The proportional use of CEA decreased by 5.0% (95% CI, -7.4% to -2.6%) per year, and TCAR use increased by 5.3% (95% CI, 2.3%-8.3%) per year. Among patients at high risk, the change was greater: CEA use decreased by 7.8% (95% CI, -11.9% to -3.8%) per year, TFCAS decreased by 4.8% (95% CI, -9.5% to -0.14%) per year, and TCAR increased by 12.6% (95% CI, 7.1%-18.1%) per year. Multinomial logistic regression showed that patient risk status was the most important characteristic associated with TCAR compared with CEA (relative risk ratio, 36.10; 95% CI, 29.24-44.66; P < .001) and TFCAS (relative risk ratio, 14.10; 95% CI, 11.86-16.66; P < .001). Linear regression revealed no association between year of surgery and in-hospital myocardial infarction, stroke, or mortality.

CONCLUSIONS AND RELEVANCE

Results of this study indicate that TCAR has become the dominant carotid revascularization approach, surpassing TFCAS and CEA in patients at high risk for stroke, cranial nerve injury, or cardiovascular events. Patient high-risk status was the main characteristic associated with a stenting approach, highlighting the perceived importance of carotid stenting therapies in this patient population.

Transcarotid Artery Revascularization: Is It Better than Carotid Endarterectomy?

Transcarotid artery revascularization (TCAR) is a novel carotid stenting method that avoids the manipulation of the aortic arch and uses a flow-reversal neuroprotection system that effectively reduces the risk of embolic events during carotid intervention. Studies have shown a lower risk of stroke or death compared with the transfemoral carotid stenting approach, and an equivalent risk of stroke or death compared with traditional carotid endarterectomy. TCAR has added benefits of lower risk of myocardial infarction, cranial nerve injuries, and shorter operative times compared with endarterectomy. TCAR has become widely adopted by vascular surgeons in the United States for the treatment of patients with high-risk medical comorbidities and those with challenging surgical anatomy.

Transcarotid artery revascularization is associated with similar outcomes to carotid endarterectomy regardless of patient risk status

BACKGROUND

Carotid artery stenting (CAS), including both transfemoral carotid artery stenting (TFCAS) and transcarotid artery revascularization (TCAR), reimbursement has been limited to high-risk patients by the Centers for Medicare & Medicaid Services (CMS) since 2005. We aimed to assess the association of CMS high-risk status with perioperative outcomes for carotid endarterectomy (CEA), TFCAS, and TCAR.

METHODS

We performed a retrospective review of all Vascular Quality Initiative patients who underwent carotid revascularization between 2015 and 2020. Patients were stratified by whether they met CMS CAS criteria, and univariable and multivariable logistic regression analyses were performed to assess the association of procedure type (CEA, TFCAS, TCAR) with perioperative outcomes.

RESULTS

Of 124,531 individuals who underwent carotid revascularization procedures, 91,687 (73.6%) underwent CEA, 17,247 (13.9%) underwent TFCAS, and 15,597 (12.5%) underwent TCAR. Among patients who met the CMS CAS criteria (ie, high-risk patients), the incidence of perioperative stroke was 2.7% for CEA, 3.4% for TFCAS, and 2.4% for TCAR (P < .001). Among standard-risk patients, the incidence of perioperative stroke was 1.7% for CEA, 2.7% for TFCAS, and 1.8% for TCAR (P < .001). After adjusting for baseline demographic and clinical characteristics, the odds of perioperative stroke were lower for TCAR versus CEA in high-risk patients (adjusted odds ratio [aOR], 0.82; 95% confidence interval [CI], 0.68-0.99) and similar in standard-risk patients (aOR, 1.05; 95% CI, 0.84, 1.31). In contrast, the adjusted odds of perioperative stroke were higher for TFCAS versus CEA in high-risk patients (aOR, 1.23; 95% CI, 1.03-1.46) and standard-risk patients (aOR, 1.60; 95% CI, 1.37-1.86). In both populations, TFCAS and TCAR patients had significantly lower odds of myocardial infarction than CEA patients (both P < .001).

CONCLUSIONS

The perioperative risks associated with CEA, TFCAS, and TCAR in high-risk patients support the current CMS criteria, although the risks associated with each revascularization approach in standard-risk patients suggest that distinguishing TCAR from TFCAS may be warranted.

How responsible is AI- identification of key public concerns using Sentiment Analysis and Topic Modeling

Many businesses around the World are adopting AI with the hope of increasing their top-line and bottom-line numbers. The COVID19 pandemic has further accelerated the journey. While AI technology promising to bring enormous benefits, the challenges come in similar proportions. In the current form, the requirements for transparency and trust are relatively low for AI systems. On the other hand, there is a lot of regulatory pressure for AI systems to be trustworthy and responsible. Challenges still exist both on the methods and theory side and how explanations are used in practice. The objective of this paper is to analyze Twitter data to extract sentiments and opinions in unstructured text. We attempted to use contextual text analytics to categorize the twitter data to understand the positive or negative sentiments and feelings for the AI Ethical challenges and highlight the key concerns. Text clustering has also been performed on positive and negative sentiments to understand the key themes behind people's concern.

SOCIETY FOR VASCULAR SURGERY CLINICAL PRACTICE GUIDELINES FOR MANAGEMENT OF EXTRACRANIAL CEREBROVASCULAR DISEASE

Management of carotid bifurcation stenosis in stroke prevention has been the subject of extensive investigations, including multiple randomized controlled trials. The proper treatment of patients with carotid bifurcation disease is of major interest to vascular surgeons and other vascular specialists. In 2011, the Society for Vascular Surgery published guidelines for treatment of carotid artery disease. At the time, several randomized trials, comparing carotid endarterectomy (CEA) and carotid artery stenting (CAS), were published. Since that publication, several studies and a few systematic reviews comparing CEA and CAS have been published, and the role of medical management has been re-emphasized. The current publication updates and expands the 2011 guidelines with specific emphasis on five areas: is carotid endarterectomy recommended over maximal medical therapy in low risk patients; is carotid endarterectomy recommended over trans-femoral carotid artery stenting in low surgical risk patients with symptomatic carotid artery stenosis of >50%; timing of carotid Intervention in patients presenting with acute stroke; screening for carotid artery stenosis in asymptomatic patients; and optimal sequence for intervention in patients with combined carotid and coronary artery disease. A separate implementation document will address other important clinical issues in extracranial cerebrovascular disease. Recommendations are made using the GRADE (Grades of Recommendation Assessment, Development and Evaluation) approach, as has been done with other Society for Vascular Surgery guidelines. The committee recommends CEA as the first-line treatment for symptomatic low risk surgical patients with stenosis of 50% to 99% and asymptomatic patients with stenosis of 70% to 99%. The perioperative risk of stroke and death in asymptomatic patients must be <3% to ensure benefit for the patient. In patients with recent stable stroke (modified Rankin 0-2), carotid revascularization is considered appropriate in symptomatic patients with greater than 50% stenosis and is recommended and performed as soon as the patient is neurologically stable after 48 hours but definitely before 14 days of onset of symptoms. In the general population, screening for clinically asymptomatic carotid artery stenosis in patients without cerebrovascular symptoms or significant risk factors for carotid artery disease is not recommended. In selected asymptomatic patients who are at increased risk for carotid stenosis, we suggest screening for clinically asymptomatic carotid artery stenosis as long as the patients would potentially be fit for and willing to consider carotid intervention if significant stenosis is discovered. In patients with symptomatic carotid stenosis 50-99%, who require both CEA and CABG, we suggest CEA before or concomitant with CABG to potentially reduce the risk of stroke and stroke/death. The sequencing of the intervention depends on clinical presentation and institutional experience.