Impact of the type of anesthesia on adverse events during transcarotid artery revascularization.

OBJECTIVE: The use of local or regional anesthesia (LRA) is encouraged during transcarotid artery revascularization (TCAR) because the procedure is performed through a small incision. LRA permits neurologic evaluation during the procedure and may reduce periprocedural cardiac morbidity compared with general anesthesia (GA). There is limited and conflicting information regarding the preferred anesthesia to use during TCAR. We compared periprocedural clinical and technical complications, and intraprocedural performance metrics of TCAR performed under GA vs LRA. METHODS: Patient, lesion, physician, and procedural information was collected in a worldwide quality assurance program of consecutive TCAR procedures. A composite clinical adverse event rate (death, stroke, transient ischemic attack, myocardial infarction) and a composite technical adverse event rate (aborted procedure, conversion to carotid endarterectomy, bleeding, dissection, cranial-nerve injury, device failure) in the periprocedural period were computed. Four intraprocedural performance measures (flow-reversal time, fluoroscopy time, contrast volume, and skin-to-skin time) were recorded. Deidentified data were analyzed independently at the Center for Vascular Research, University of Maryland. Poisson regressions were used to assess the impact of anesthesia type on adverse event rates. Linear regressions were used to compare performance measures. RESULTS: A total of 27,043 TCARs were performed by 1456 physicians between 2012 and 2021. A majority of patients (83%) received GA, and this proportion increased over time (R2 = 0.74; P < .0001). Some physicians (33.4%) used LRA in some of their procedures; only 2.7% used LRA in all of their procedures. Clinical risk factors were more common in the LRA group (P < .0001) and anatomic risk factors in the GA group (P < .0001); these differences were adjusted for in subsequent analyses. LRA was more likely to be used by vascular surgeons and by physicians with higher prior transfemoral carotid stenting experience (P < .0001). When comparing GA vs LRA, clinical adverse events (1.49%; 95% confidence interval [CI], 1.3-1.8 vs 1.55%; 95% CI, 1.2-2.0; P = .78), technical adverse events (5.6%; 95% CI, 5.2-6.2 vs 5.3%; 95% CI, 4.5-6.3; P = .47), and intraprocedural performance measures did not differ by type of anesthesia. CONCLUSIONS: Almost two-thirds of physicians performed TCAR exclusively under GA, and the overall proportion of procedures performed under GA increased over time. A larger fraction of patients with severe medical risk factors received LRA vs GA, whereas a larger fraction of patients with anatomic risk-factors received GA. Periprocedural clinical and technical adverse events did not differ by type of anesthesia. Intraprocedural performance metrics that drive procedural cost were similar between groups; potential differences in procedural cost driven by anesthetic choice require further study.

A Scoping Review of Simulation-Based Training Paradigms for Carotid Artery Endarterectomy and Carotid Artery Stenting.

BACKGROUND: Surgical simulation has come to the forefront to enhance the training of residents. The aim of our scoping review is to analyze the available simulation-based carotid revascularization techniques, including carotid endarterectomy (CEA) and carotid artery stenting (CAS) and suggest critical steps for evaluating competency in a standardized fashion. METHODS: A scoping review of all reports on simulation-based carotid revascularization techniques including CEA and CAS was performed in PubMed/MEDLINE, Scopus, Embase, Cochrane, Science Citation Index Expanded, Emerging Sources Citation Index, and Epistemonikos databases. Data were collected according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. The English language literature was searched from January 1, 2000 to January 9, 2022. The outcomes evaluated included measures of assessment of operator performance. RESULTS: Five CEA and 11 CAS manuscripts were included in this review. The methods of assessments employed by these studies to judge performance were comparable. The 5 CEA studies sought to validate and demonstrate improved performance with training or distinguish surgeons by their experience level, either through assessing operative performance or end-product results. The 11 CAS studies used 1 of 2 types of commercial simulators and focused on determining the efficacy of simulators as teaching tools. By examining the steps of the procedure associated with preventable perioperative complications, it provides a reasonable framework for determining which elements of the procedure should be emphasized most. Furthermore, using potential errors as a basis for assessment of competency could reliably distinguish operators based on level of experience. CONCLUSIONS: Competency-based simulation training is becoming more relevant as our surgical training paradigm shifts with the increased scrutiny within training programs of work-hour regulations and the need to develop a curriculum to assess our trainees' ability to perform specific operations competently during their stipulated training period. Our review has given us an insight into the current efforts in this space regarding 2 specific procedures that are key for all vascular surgeons to master. Although many competency-based modules are available, there is a lack of standardization in the grading/rating system of what surgeons consider vital steps of each procedure to assess these simulation-based modules. Therefore, the next steps of curriculum development should be based on standardization efforts for the different protocols available.

Transcarotid revascularization outcomes do not differ by patient age or sex.

BACKGROUND: Transcarotid artery revascularization (TCAR) is a hybrid approach to carotid revascularization. Limited information is available on the differences in periprocedural complications and performance measures of TCAR for men compared with women and for older vs younger adults. METHODS: The patient, lesion, and physician characteristics were collected for all TCAR procedures performed by each physician worldwide in an international quality assurance database between March 3, 2009 and May 7, 2020. Clinical composite (ie, death, stroke, transient ischemic attack, myocardial infarction) and technical composite (ie, aborted procedure, conversion to surgery, bleeding, dissection, cranial nerve injury, device failure) adverse events within 24 hours of the procedure were recorded. Four performance measures were recorded: flow-reversal time, fluoroscopy time, contrast volume, and skin-to-skin time. Poisson regressions were used to assess the effects of age and sex on the incidence of clinical and technical composite adverse events. Linear regressions were used to compare the four performance measures. RESULTS: A total of 18,240 TCARs were performed by 1273 physicians; 34.9% of the patients were women and 37.5% were symptomatic. The overall incidence of clinical and technical composite adverse events was low. The adjusted clinical (1.62% [95% confidence interval (CI), 1.17%-2.23%] vs 1.35% [95% CI, 1.01%-1.79%]; P = .22) and technical (7.84% [95% CI, 6.85%-8.97%] vs 7.80% [95% CI, 6.94%-8.77%]; P = .93) composite adverse event rates did not vary for women vs men. The adjusted clinical (P = .65) and technical (P = .55) composite adverse event rates also did not vary by age. The adjusted skin-to-skin time was shorter for the women (76.6 minutes; 95% CI, 74.6-78.6) than for the men (77.7 minutes; 95% CI, 75.7-79.6; P = .002). Significant differences were found by age group for fluoroscopy time, flow-reversal time, and skin-to-skin time, although the magnitude of these differences was small (<1 minute for each). CONCLUSIONS: The clinical and technical outcomes of TCAR are not affected by age or sex. We found clinically minor differences in the procedural performance measures when stratified by age and sex. In addition to being safe for younger individuals, TCAR could also be the preferred method for performing carotid stenting in women and older patients, in particular, older women.

Learning curve and proficiency metrics for transcarotid artery revascularization.

BACKGROUND: When introduced to a new procedure, physicians improve their performance and reduce their procedural adverse event rates rapidly during the initial cases and then improvement slows, signaling that proficiency has been achieved. Determining when they have acquired proficiency has important implications for procedural innovation, education, credentialing, and patient safety. We analyzed the worldwide experience with transcarotid artery revascularization (TCAR), a hybrid approach to carotid revascularization, to identify the (1) procedural performance measures associated with clinical and technical adverse events; (2) target levels of performance measures that minimize adverse event rates; and (3) number of TCAR cases needed to achieve the target levels for the performance measures. METHODS: The patient, lesion, and physician characteristics were collected for each TCAR procedure performed by each physician worldwide in an international quality assurance database. Four procedural performance measures were recorded for each procedure: flow-reversal time, fluoroscopy time, contrast volume, and total skin-to-skin time. Composite clinical adverse events (ie, transient ischemic attack, stroke, myocardial infarction, death) and composite technical adverse events (ie, aborted procedure, conversion to surgery, bleeding, dissection, cranial nerve injury, device failure), occurring within 24 hours were also recorded. Correlations between each performance measure and the clinical and technical adverse event rates were computed. The inflection points in the performance measures were identified at which no further improvements occurred in the adverse event rates. Finally, the minimum number of TCAR cases required to achieve the target performance measure levels was computed. RESULTS: A total of 18,240 procedures performed by 1273 physicians were analyzed. Of the 18,240 patients, 34.9% were women and 62.5% were asymptomatic. The flow-reversal time correlated with clinical adverse events adjusted for age, sex, and symptomatic status (R2 = 0.91; P < .0001) and adjusted technical adverse events (R2 = 0.86; P < .0001). The skin-to-skin time correlated with adjusted technical adverse events (R2 = 0.92; P < .0001). A reduction in flow-reversal times to <13.1 minutes and the skin-to-skin time to <81 minutes did not translate into further improvements in the adverse event rates. A minimum of 26 TCAR cases was required to achieve the target flow-reversal time, and a minimum of 15 cases was required to achieve the target skin-to-skin time. CONCLUSIONS: The flow-reversal time and skin-to-skin time are appropriate performance measures for establishing the level of expertise of physicians as they acquire skills to perform TCAR. A target time of ≤13.1 minutes for flow-reversal and 81 minutes for skin-to-skin time minimized the adverse event rates. Familiarity with the steps involved in performing TCAR was achieved after ≥15 cases, and minimizing clinical adverse events occurred after ≥26 cases.

Risk Factors for and Intraoperative Management of Intolerance to Flow Reversal in TCAR.

BACKGROUND: In patients deemed high risk for carotid endarterectomy (CEA) who are indicated for treatment of carotid artery stenosis (CAS), transcarotid artery revascularization (TCAR) has been demonstrated as a safe and effective alternative to trans-femoral carotid artery stenting (TF-CAS). Compared to CEA, where approx. 12% of patients undergoing awake intervention do not tolerate internal carotid artery (ICA) clamping, only 1-2% of patients were observed to have intolerance to flow reversal during TCAR based on data from the ROADSTER1/2 trials. This study reviewed awake interventions from those trials to assess factors associated with intolerance to flow reversal and review how those cases were managed. METHODS: This is a retrospective review of prospectively collected data from Reverse Flow Used During Carotid Artery Stenting Procedure (ROADSTER) multicenter trial along with the subsequent post-approval (ROADSTER-2) trial. The subset of patients from both trials undergoing awake TCAR was analyzed to compare demographics, procedural details, and anatomic factors between patients who did and did not experience intolerance to reversal of flow to assess for predisposing factors. Patients were deemed intolerant to flow reversal at the discretion of the operator, often related to changes in completion of neurologic tasks, hemodynamic stability, or patient reported symptoms. RESULTS: A total of 103 patients from ROADSTER and 194 patients from ROADSTER-2 underwent TCAR under local/regional anesthesia. Of these, 8 patients had intolerance to flow reversal, though all cases were successfully completed. While intraoperative hemodynamic data was only available for 5 of the 8 intolerant patients, none experienced hypotension. 4 cases were completed under low flow reversal, 3 cases were successfully weaned from low to high flow over several minutes, and 1 case required general anesthesia. No significant association was found between intolerance to flow reversal and comorbidities including diabetes mellitus (DM), hypertension (HTN), hyperlipidemia (HLD), congestive heart failure (CHF), prior MI or angina, pre-op CAS-related symptoms, prior stroke, prior CAS or CEA, prior neck radiation, tandem stenosis, high cervical stenosis, or hostile neck. A trend towards significance was seen with chronic obstructive pulmonary disease (COPD) and contralateral carotid artery occlusion (P = 0.086 and 0.139, respectively). CONCLUSIONS: Despite intolerance to flow reversal, TCAR cases were successfully completed by adjusting reversal-of-flow rate and do not typically require conversion to GETA. While factors contributing to intolerance of flow reversal during TCAR remain poorly understood, this study identified a trend towards significance with an association of preexisting COPD and contralateral carotid artery occlusion. Given the low number of patients who experienced this issue, a larger sample size is required to better elucidate these trends.

Evaluating the optimal training paradigm for transcarotid artery revascularization based on worldwide experience.

BACKGROUND: Transcarotid artery revascularization (TCAR) is a new hybrid approach to carotid artery revascularization. Proctored training on live cases is an effort-, time-, and resource-intensive approach to learning new procedures. We analyzed the worldwide experience with TCAR to develop objective performance metrics for the procedure and compared the effectiveness of training physicians using cadavers or synthetic models to that of traditional in-person training on live cases. METHODS: Physicians underwent one of three mandatory training programs: (1) in-person proctoring on live TCAR procedures, (2) supervised training on human cadavers, and (3) supervised training on synthetic models. The training details and information from all subsequent independently performed TCAR procedures were recorded. The composite clinical adverse events (ie, transient ischemic attack, stroke, myocardial infarction, death) and composite technical adverse events (ie, aborted procedure, conversion to surgery, bleeding, dissection, cranial nerve injury, or device failure, occurring within 24 hours were recorded). Four procedural proficiency measures were recorded: procedure time, flow-reversal time, fluoroscopy time, and contrast volume. We compared the adverse event rates between the procedures performed by physicians after undergoing the three training modes and tested whether the proficiency measures achieved during TCAR after training on cadavers and synthetic models were noninferior to proctored training. RESULTS: From March 3, 2009 to May 7, 2020, 1160 physicians had undergone proctored (19.1%), cadaver-based (27.4%), and synthetic model-based (53.5%) TCAR training and had subsequently performed 17,283 TCAR procedures. The proctored physicians had treated younger patients and more patients with asymptomatic carotid stenosis and had had more prior experience with transfemoral carotid stenting. The overall 24-hour composite clinical and technical adverse event rates, adjusted for age, sex, and symptomatic status, were 1.0% (95% confidence interval, 0.8%-1.3%) and 6.0% (95% confidence interval, 5.4%-6.6%), respectively, and did not differ significantly by training mode. The proficiency measures of cadaver-trained and synthetic model-trained physicians were not inferior to those for the proctored physicians. CONCLUSIONS: We have presented key objective proficiency metrics for performing TCAR and an analytic framework to assess adequate training for the procedure. Training on cadavers or synthetic models achieved clinical outcomes, technical outcomes, and proficiency measures for subsequently performed TCAR procedures similar to those achieved with training using traditional proctoring on live cases.

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 anatomic 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 is 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: Carotid artery stenting can be a 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 internal carotid artery sign, and carotid diameters outside the acceptable range. In carefully chosen lesions with the absence of the unfavorable characteristics described, transcarotid artery revascularization may offer improved periprocedural success and carotid artery stenting may attain better long-term durability.

Low-frequency avoidable errors during transcarotid artery revascularization.

OBJECTIVE: Transcarotid artery revascularization (TCAR) seems to be a safe and effective alternative to carotid endarterectomy (CEA) and transfemoral carotid artery stenting (TF-CAS). The TCAR system represents a paradigm shift in the management of carotid artery stenosis with potential for a significant decrease in periprocedural morbidity. However, as with CEA or TF-CAS, TCAR is associated with infrequent complications related to user technical error, most of which are preventable. Our goal is to describe these low-frequency events, and to provide guidelines for avoiding them. METHODS: The U.S. Food and Drug Administration (FDA) requires that all medical device manufacturers create a system for receiving, reviewing, and evaluating complaints (Code 21 of Federal Regulations 820.198). Silk Road Medical, Inc (Sunnyvale, Calif), has established a process by which all feedback, including complaints that may not meet FDA criteria, is captured and stored in a database for detailed analysis. More than 13,300 cases have been performed; submitted complaints were reviewed for incidents of serious injury and periprocedural complications, above and beyond the device-related events that must be reported to the FDA. RESULTS: A total of 13,334 patients have undergone TCAR worldwide between early 2011 and December 2019 using the SilkRoad device. Reported complications included 173 dissections (1.4% overall rate) of the common carotid artery at the access point, of which 22.5% were managed without intervention or with medical therapy alone and 24.3% were converted to CEA (considered failing safely). Errors in the location of stent deployment occurred in 16 cases (0.13%), with the most common site being the external carotid artery (75%). One wrong side carotid artery stent was placed in a patient with a high midline pattern of the bovine arch. Cranial nerve injury was reported in 11 cases (0.08%), only one of which persisted beyond 3 months. There have been three reported pneumothoraces and one reported chylothorax. Many of these errors can be recognized and prevented with careful attention to detail. CONCLUSIONS: In high-risk patients requiring treatment for carotid artery stenosis, TCAR has been proven as an alternative to TF-CAS with an excellent safety profile. As with CEA or TF-CAS, this procedure has the potential for infrequent complications, often as a result of user technical error. Although significant, these events can be avoided through a review of the collective experience to date and recognition of potential pitfalls, as we have described.

Vascular Anatomy Predicts the Risk of Cerebral Ischemia in Patients Randomized to Carotid Stenting Versus Endarterectomy.

BACKGROUND AND PURPOSE: Complex vascular anatomy might increase the risk of procedural stroke during carotid artery stenting (CAS). Randomized controlled trial evidence that vascular anatomy should inform the choice between CAS and carotid endarterectomy (CEA) has been lacking. METHODS: One-hundred eighty-four patients with symptomatic internal carotid artery stenosis who were randomly assigned to CAS or CEA in the ICSS (International Carotid Stenting Study) underwent magnetic resonance (n=126) or computed tomographic angiography (n=58) at baseline and brain magnetic resonance imaging before and after treatment. We investigated the association between aortic arch configuration, angles of supra-aortic arteries, degree, length of stenosis, and plaque ulceration with the presence of ≥1 new ischemic brain lesion on diffusion-weighted magnetic resonance imaging (DWI+) after treatment. RESULTS: Forty-nine of 97 patients in the CAS group (51%) and 14 of 87 in the CEA group (16%) were DWI+ (odds ratio [OR], 6.0; 95% confidence interval [CI], 2.9-12.4; P<0.001). In the CAS group, aortic arch configuration type 2/3 (OR, 2.8; 95% CI, 1.1-7.1; P=0.027) and the degree of the largest internal carotid artery angle (≥60° versus <60°; OR, 4.1; 95% CI, 1.7-10.1; P=0.002) were both associated with DWI+, also after correction for age. No predictors for DWI+ were identified in the CEA group. The DWI+ risk in CAS increased further over CEA if the largest internal carotid artery angle was ≥60° (OR, 11.8; 95% CI, 4.1-34.1) than if it was <60° (OR, 3.4; 95% CI, 1.2-9.8; interaction P=0.035). CONCLUSIONS: Complex configuration of the aortic arch and internal carotid artery tortuosity increase the risk of cerebral ischemia during CAS, but not during CEA. Vascular anatomy should be taken into account when selecting patients for stenting. CLINICAL TRIAL REGISTRATION: URL: http://www.isrctn.com/ISRCTN25337470. Unique identifier: ISRCTN25337470.

Results of the ROADSTER multicenter trial of transcarotid stenting with dynamic flow reversal.

OBJECTIVE: This report presents the 30-day results of the Safety and Efficacy Study for Reverse Flow Used During Carotid Artery Stenting Procedure (ROADSTER) multicenter trial and evaluates the safety and efficacy of ENROUTE Transcarotid NPS (Silk Road Medical Inc, Sunnyvale, Calif), a novel transcarotid neuroprotection system that provides direct surgical common carotid access and cerebral embolic protection via high-rate flow reversal during carotid artery stenting (CAS). METHODS: A prospective, single-arm, multicenter clinical trial was performed to evaluate the use of the ENROUTE Transcarotid NPS during CAS procedures performed in patients considered to be at high risk for complications from carotid endarterectomy. Symptomatic patients with ≥50% stenosis and asymptomatic patients with ≥70% stenosis were eligible to be treated with any U.S. Food and Drug Administration-approved carotid artery stent. The primary end point was the composite of all stroke, myocardial infarction (MI), and death at 30 days postprocedure as defined in the Food and Drug Administration-approved study protocol. Secondary end points included cranial nerve injury; 30-day stroke, death, stroke/death, and MI; acute device, technical, and procedural success; and access site complications. All major adverse events were adjudicated by an independent clinical events committee. RESULTS: Between November 2012 and July 2014, 208 patients were enrolled at 18 sites. Sixty-seven patients were enrolled as lead-in cases, and 141 were enrolled in the pivotal phase. In the pivotal cohort, 26% were symptomatic and 75% were asymptomatic. Acute device and technical success were 99% (140 of 141). By hierarchical analysis, the all-stroke rate in the pivotal group was 1.4% (2 of 141), stroke and death was 2.8% (4 of 141), and stroke, death and MI was 3.5% (5 of 141). One patient (0.7%) experienced postoperative hoarseness from potential Xth cranial nerve injury, which completely resolved at the 6-month follow-up visit. CONCLUSIONS: The results of the ROADSTER trial demonstrate that the use of the ENROUTE Transcarotid NPS is safe and effective at preventing stroke during CAS. The overall stroke rate of 1.4% is the lowest reported to date for any prospective, multicenter clinical trial of CAS.

Carotid artery stenting: an update.

In patients with carotid disease, the purpose of carotid artery revascularization is stroke prevention. For >50 years, carotid endarterectomy has been considered the standard treatment for severe asymptomatic and symptomatic carotid stenoses. Carotid artery stenting (CAS) has emerged in the last 15 years as minimally invasive alternative to surgery. However, the value of the endovascular approach in the management of carotid disease patients remains highly controversial. The aims of this review are to elucidate the current role of CAS, to describe the major technology advancements in the field, and to speculate about the future of this therapy.

Status update and interim results from the asymptomatic carotid surgery trial-2 (ACST-2).

OBJECTIVES: ACST-2 is currently the largest trial ever conducted to compare carotid artery stenting (CAS) with carotid endarterectomy (CEA) in patients with severe asymptomatic carotid stenosis requiring revascularization. METHODS: Patients are entered into ACST-2 when revascularization is felt to be clearly indicated, when CEA and CAS are both possible, but where there is substantial uncertainty as to which is most appropriate. Trial surgeons and interventionalists are expected to use their usual techniques and CE-approved devices. We report baseline characteristics and blinded combined interim results for 30-day mortality and major morbidity for 986 patients in the ongoing trial up to September 2012. RESULTS: A total of 986 patients (687 men, 299 women), mean age 68.7 years (SD ± 8.1) were randomized equally to CEA or CAS. Most (96%) had ipsilateral stenosis of 70-99% (median 80%) with contralateral stenoses of 50-99% in 30% and contralateral occlusion in 8%. Patients were on appropriate medical treatment. For 691 patients undergoing intervention with at least 1-month follow-up and Rankin scoring at 6 months for any stroke, the overall serious cardiovascular event rate of periprocedural (within 30 days) disabling stroke, fatal myocardial infarction, and death at 30 days was 1.0%. CONCLUSIONS: Early ACST-2 results suggest contemporary carotid intervention for asymptomatic stenosis has a low risk of serious morbidity and mortality, on par with other recent trials. The trial continues to recruit, to monitor periprocedural events and all types of stroke, aiming to randomize up to 5,000 patients to determine any differential outcomes between interventions. CLINICAL TRIAL: ISRCTN21144362.

Improving results for carotid artery stenting by validation of the anatomic scoring system for carotid artery stenting with patient-specific simulated rehearsal.

OBJECTIVE: Carotid artery stenting (CAS) is a technically demanding procedure with a risk of periprocedural stroke. A scoring system based on anatomic criteria has been developed to facilitate patient selection for CAS. Advancements in simulation science also enable case evaluation through patient-specific virtual reality (VR) rehearsal on an endovascular simulator. This study aimed to validate the anatomic scoring system for CAS using the patient-specific VR technology. METHODS: Three patients were selected and graded according to the CAS scoring system (maximum score, 9): one easy (score, <4.9), one intermediate (score, 5.0-5.9), and one difficult (score, >7.0). The three cases were performed on the simulator in random order by 20 novice interventionalists pretrained in CAS. Technical performances were assessed using simulator-based metrics and expert-based ratings. RESULTS: The interventionalists took significantly longer to perform the difficult CAS case (median, 31.6 vs 19.7 vs 14.6 minutes; P<.0001) compared with the intermediate and easy cases; similarly, more fluoroscopy time (20.7 vs 12.1 vs 8.2 minutes; P<.0001), contrast volume (56.5 vs 51.5 vs 50.0 mL; P=.0060), and roadmaps (10 vs 9 vs 9; P=.0040) were used. The quality of performance declined significantly as the cases became more challenging (score, 24 vs 22 vs 19; P<.0001). CONCLUSIONS: The anatomic scoring system for CAS can predict the difficulty of a CAS procedure as measured by patient-specific VR. This scoring system, with or without the additional use of patient-specific VR, can guide novice interventionalists in selecting appropriate patients for CAS. This may reduce the perioperative stroke risk and enhance patient safety.

Asymptomatic carotid disease and cardiac surgery consensus.

The Carotid Disease and Cardiac Surgery Consensus Meeting was convened as a multidisciplinary gathering to consider the management of patients undergoing cardiac surgery who are found to have asymptomatic carotid artery disease. There are no randomized trials concerning whether carotid interventions are of value in this situation and the natural history is unclear. Bilateral carotid artery disease (≥70% stenosis) should be regarded clinically relevant when considering hemodynamic and short-term surgical stroke risk. However, this may be because the presence of significant carotid disease is also a marker for aortic arch and intracerebral disease. A natural history study is urgently needed to determine the incidence, predictive factors, and natural history of asymptomatic carotid disease in patients undergoing contemporary cardiac surgical interventions to inform the design of any future randomized trial.

Carotid artery stenting compared with endarterectomy in patients with symptomatic carotid stenosis (International Carotid Stenting Study): an interim analysis of a randomised controlled trial.

BACKGROUND: Stents are an alternative treatment to carotid endarterectomy for symptomatic carotid stenosis, but previous trials have not established equivalent safety and efficacy. We compared the safety of carotid artery stenting with that of carotid endarterectomy. METHODS: The International Carotid Stenting Study (ICSS) is a multicentre, international, randomised controlled trial with blinded adjudication of outcomes. Patients with recently symptomatic carotid artery stenosis were randomly assigned in a 1:1 ratio to receive carotid artery stenting or carotid endarterectomy. Randomisation was by telephone call or fax to a central computerised service and was stratified by centre with minimisation for sex, age, contralateral occlusion, and side of the randomised artery. Patients and investigators were not masked to treatment assignment. Patients were followed up by independent clinicians not directly involved in delivering the randomised treatment. The primary outcome measure of the trial is the 3-year rate of fatal or disabling stroke in any territory, which has not been analysed yet. The main outcome measure for the interim safety analysis was the 120-day rate of stroke, death, or procedural myocardial infarction. Analysis was by intention to treat (ITT). This study is registered, number ISRCTN25337470. FINDINGS: The trial enrolled 1713 patients (stenting group, n=855; endarterectomy group, n=858). Two patients in the stenting group and one in the endarterectomy group withdrew immediately after randomisation, and were not included in the ITT analysis. Between randomisation and 120 days, there were 34 (Kaplan-Meier estimate 4.0%) events of disabling stroke or death in the stenting group compared with 27 (3.2%) events in the endarterectomy group (hazard ratio [HR] 1.28, 95% CI 0.77-2.11). The incidence of stroke, death, or procedural myocardial infarction was 8.5% in the stenting group compared with 5.2% in the endarterectomy group (72 vs 44 events; HR 1.69, 1.16-2.45, p=0.006). Risks of any stroke (65 vs 35 events; HR 1.92, 1.27-2.89) and all-cause death (19 vs seven events; HR 2.76, 1.16-6.56) were higher in the stenting group than in the endarterectomy group. Three procedural myocardial infarctions were recorded in the stenting group, all of which were fatal, compared with four, all non-fatal, in the endarterectomy group. There was one event of cranial nerve palsy in the stenting group compared with 45 in the endarterectomy group. There were also fewer haematomas of any severity in the stenting group than in the endarterectomy group (31 vs 50 events; p=0.0197). INTERPRETATION: Completion of long-term follow-up is needed to establish the efficacy of carotid artery stenting compared with endarterectomy. In the meantime, carotid endarterectomy should remain the treatment of choice for patients suitable for surgery. FUNDING: Medical Research Council, the Stroke Association, Sanofi-Synthélabo, European Union.

Is carotid artery stenting equivalent or superior to carotid endarterectomy for treatment of carotid artery stenosis?

A best evidence topic in vascular surgery was written according to a structured protocol. The question addressed was whether carotid artery stenting (CAS) is equivalent or even superior to carotid endarterectomy (CEA) for the treatment of significant carotid artery stenosis. Four hundred and ninety-four papers were identified, of which 14 papers including five randomised controlled trials (RCTs) presented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. We conclude that the risk of peri-procedure stroke or death was similar for patients treated with carotid artery angioplasty+/-stenting and those treated with surgery. However, CAS did reduce the risk of minor complications at the site of vascular access, the incidence of cranial nerve injury, and may reduce economic costs due to shorter hospital stays and earlier return to work. Long term follow-up of these patients is, however, lacking. There are currently four large multi-centre RCTs in progress and their results will determine whether CAS will surpass CEA as the gold standard in the future.

Outpatient vascular intervention: a two-year experience.

PURPOSE: To retrospectively analyze the outcome of a range of interventional vascular procedures performed on outpatients. METHODS: Suitability for outpatient procedures was assessed according to agreed protocols. An episode was defined as any procedure/s through a single access site at one attendance. Retrospective case-note review was performed. RESULTS: There were 693 outpatient episodes between April 1998 and May 2000 (290 interventional, and 403 diagnostic procedures), comprising 25% (693/2,769) of the total workload. Follow-up is available in 214; 38 of these were transfers from outlying hospitals and were excluded from analysis. One hundred and seventy-six were true outpatients. There were 98 iliac and 46 femoropopliteal interventions, 2 aortic stents, 1 renal and 5 upper-limb angioplasties (PTAs), 5 embolizations, 8 Hickman lines, 1 line stripping, 3 atherectomies, 1 dialysis-graft PTA and 6 bypass-graft PTAs. Sixty-eight closure devices were used. Twelve patients were converted to inpatients (6.8%, 12/176). The readmission rate was 3.4% (6/176). The reattendance rate was 1.1% (2/176), both subsequently attending for outpatient duplex ultrasound examination to exclude pseudoaneurysm. The major complication rate was 3.4% and the delayed major complication rate was 1.7%. CONCLUSION: Outpatient vascular intervention is safe with appropriate protocols and with careful patient selection. Local vascular services benefit from the release of inpatient beds.

Protected carotid stenting: safety and efficacy of the MedNova NeuroShield filter.

OBJECTIVE: Neuroprotection during carotid stenting has the potential to reduce procedural atheroembolic sequelae. We report the United Kingdom experience of NeuroShield (MedNova Ltd, Horsham, West Sussex, United Kingdom). METHODS: We performed a prospective cohort analysis of 50 consecutive patients (50 lesions) in a regional vascular tertiary referral center (catchment area one million) that provides an institutional service for the short term. The subjects were all the patients referred for carotid stenting after preassessment by a multidisciplinary team. All the patients underwent pretreatment with antiplatelet agents. Forty-two patients had atherosclerotic stenosis of the carotid bifurcation between 70% and 95% (with North American Symptomatic Carotid Endarterectomy Trial criteria). Six patients had restenosis after endarterectomy. Two had previous local radiotherapy. Forty-two patients were symptomatic (amaurosis fugax/central retinal artery occlusion in 11 cases, and hemispheric transient ischemic attack/cerebrovascular accident in 31 cases). Eight patients were asymptomatic with bilateral high-grade stenoses, with six cases before coronary artery bypass grafting. The intervention performed was protected primary carotid stenting. Outcome measures were procedural atheroembolic events, including all-stroke and death rates up to 30 days, and analysis of retrieved debris in a subset of 11 cases. RESULTS: The technical success rate was 50/50 (100%) for stenting and 49/50 (98%) for filter placement/retrieval. Technical complications comprised nonsymptomatic spasm at the filter site (flow limiting in two cases and non-flow limiting in five cases). Procedural events were one minor stroke (patient fully recovered within 48 hours) in a complex clinical setting and one ventricular fibrillation arrest in a patient before coronary artery bypass grafting who was resuscitated without neurologic event. At 30 days, the death or major disability from stroke rate was 2/50 (4%). No cases were atheroembolic. The all-stroke/death rate was 3/50 (6%). The two deaths were the result of a fatal hemorrhagic stroke that occurred at 4 days and was thought to be caused by reperfusion and a perforated ventricle caused by a temporary pacing wire. One femoral pseudoaneurysm followed failed closure device deployment and required percutaneous thrombin injection. The mean particle number per patient was 12 (range, 0 to 41). The mean particle diameter was 284.9 microm(range, 31 to 1430 microm). The mean ellipsoid volume load was 0.1602 mm(3) (range, 0.0005 to 0.1968 mm(3)). CONCLUSION: Carotid stenting protected with NeuroShield is safe. The filter traps embolic debris liberated during the procedure.