Credentialing of surgeons as interventionalists for carotid artery stenting: Experience from the lead-in phase of CREST

Long-term outcomes of carotid endarterectomy vs transfemoral carotid stenting in a Medicare-matched database

BACKGROUND

Carotid endarterectomy (CEA) is associated with lower risk of perioperative stroke compared with transfemoral carotid artery stenting (TFCAS) in the treatment of carotid artery stenosis. However, there is discrepancy in data regarding long-term outcomes. We aimed to compare long-term outcomes of CEA vs TFCAS using the Medicare-matched Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network database.

METHODS

We assessed patients undergoing first-time CEA or TFCAS in Vascular Quality Initiative Vascular-Vascular Implant Surveillance and Interventional Outcomes Network from January 2003 to December 2018. Patients with prior history of carotid revascularization, nontransfemoral stenting, stenting performed without distal embolic protection, multiple or nonatherosclerotic lesions, or concomitant procedures were excluded. The primary outcome of interest was all-cause mortality, any stroke, and a combined end point of death or stroke. We additionally performed propensity score matching and stratification based on symptomatic status.

RESULTS

A total of 80,146 carotid revascularizations were performed, of which 72,615 were CEA and 7531 were TFCAS. CEA was associated with significantly lower risk of death (57.8% vs 70.4%, adjusted hazard ratio [aHR], 0.46; 95% confidence interval [CI], 0.41-0.52; P < .001), stroke (21.3% vs 26.6%; aHR, 0.63; 95% CI, 0.57-0.69; P < .001) and combined end point of death and stroke (65.3% vs 76.5%; HR, 0.49; 95% CI, 0.44-0.55; P < .001) at 10 years. These findings were reflected in the propensity-matched cohort (combined end point: 34.6% vs 46.8%; HR, 0.53; 95% CI, 0.46-0.62) at 4 years, as well as stratified analyses of combined end point by symptomatic status (asymptomatic: 63.2% vs 74.9%; HR, 0.49; 95% CI, 0.43-0.58; P < .001; symptomatic: 69.9% vs 78.3%; HR, 0.51; 95% CI, 0.45-0.59; P < .001) at 10 years.

CONCLUSIONS

In this analysis of North American real-world data, CEA was associated with greater long-term survival and fewer strokes compared with TFCAS. These findings support the continued use of CEA as the first-line revascularization procedure.

Patient Selection Criteria and Procedural Standardization for Carotid Artery Stenting-A Single Center Experience

The gold standard for the treatment of carotid artery stenosis is the carotid endarterectomy (CEA). According to current guidelines, carotid artery stenting (CAS) is an alternative. Randomized control trials (RCTs) show significantly higher rates of peri-interventional strokes after CAS compared to CEA. However, these trials were usually characterized by a great heterogeneity in the CAS procedure. In this retrospective analysis from 2012 to 2020, 202 symptomatic and asymptomatic patients were treated with CAS. Patients were carefully pre-selected according to anatomical and clinical criteria. In all cases, the same steps and material were used. All interventions were performed by five experienced vascular surgeons. Primary endpoints of this study were perioperative death and stroke. Asymptomatic carotid stenosis was present in 77% of the patients and symptomatic in 23%. The mean age was 66 years. The average degree of stenosis was 81%. The CAS technical success rate was 100%. Periprocedural complications occurred in 1.5% of cases, including one major stroke (0.5%) and two minor strokes (1%). The results of this study indicate that through a strict patient selection based on anatomical and clinical criteria, CAS can be performed with very low complication rates. Furthermore, standardization of the materials and the procedure itself is crucial.

Results of carotid artery stenting. Lessons learned in a Belgian 'real world' practice

OBJECTIVE/BACKGROUND

Carotid artery stenting (CAS) is a valuable solution for the treatment of carotid artery stenosis in a high-risk patient population for carotid endarterectomy (CEA). In literature however, there are concerns about the death and stroke rates of CAS in the 'real world' practice. Since Belgium is a small country with a broad offer of medical care, and there is no reimbursement for CAS, only small numbers of patients can be treated per vascular department.

METHODS

In our department 45 CAS were performed from January 2006 until May 2018. Patient characteristics, indication for treatment and choice of treatment, minor stroke, major stroke and death rates were analyzed retrospectively.

RESULTS

Of these patients 8/45 (18%) had a symptomatic carotid artery stenosis and 37/45 (82%) had an asymptomatic stenosis. A total minor stroke rate of 3/45 (6.6%) was recorded, but no major stroke (0%) or death (0%). Of the 37 patients who were asymptomatic at the start, 1 suffered a minor stroke (1/37, 2.7%) peri-operatively.

CONCLUSION

Real world data from a low volume center show that CAS performed in patients with high risk for CEA yields acceptable outcome that is comparable to the literature. Since CAS is a delicate procedure we advice to centralize the procedure to an dedicated experienced interventionalist and to perform rigorous quality control of your 'real world' data.

Evaluation of tools to assess operative competence in endovascular procedures: a systematic review

BACKGROUND

With an increase in the use of endovascular interventions as an alternative to open surgery and the unique technical skills required, current methods for assessing the competence of vascular surgery trainees may not be optimal, suggesting a need for a shift in assessment modalities. We conducted this systematic review to explore current assessment methods used in vascular surgery training to assess competence specific to endovascular procedures.

METHODS

A comprehensive literature search was performed with a structured search strategy using terms focusing on endovascular procedures and assessment. Inclusion and exclusion criteria were used in order to screen for suitable articles.

RESULTS

We identified 54 articles that satisfied the inclusion criteria. These included a single randomized controlled trial, a single systematic review, a single narrative review and a single literature review, with the vast majority having level 2 evidence. Global rating scales, proficiency assessments and written/oral examinations were described as standard current assessment tools. These modalities lack reproducibility and objectivity, neglecting the needs of assessment of endovascular procedures requiring specialized decision making and finger dexterity. Novel methods such as high fidelity simulation and virtual reality promote reproducible and objective assessment methods in the context of endovascular surgery, and have a promising future.

CONCLUSION

While current assessment methods in vascular surgery are widely supported the changing skills required of a vascular surgery trainee warrants a shift in assessment modalities to better align to these requirements. High fidelity simulations show promise, although they require more extensive research to understand their relative merits.

A systematic review and meta-analysis of complication rates after carotid procedures performed by different specialties

OBJECTIVE

Different competencies and skills are required and obtained during medical specialization. However, whether these have an impact on procedural outcomes of carotid endarterectomy (CEA) or carotid artery stenting (CAS) is unclear. We assessed the reported association between operator specialization and procedural outcomes after CEA or CAS to determine whether CEA and CAS should be performed by specific specialties.

METHODS

We systematically searched PubMed and Embase up to August 21, 2017, for randomized clinical trials and observational studies that compared two or more specialties performing CEA or CAS for symptomatic and asymptomatic carotid artery stenosis. The composite primary outcome was procedural stroke or death (ie, occurring within 30 days of the procedure or before discharge). Risk estimates were pooled with a generic inverse variance random effects model.

RESULTS

A total of 35 studies (26 providing data on CEA, 8 providing data on CAS, and 1 providing data on both CEA and CAS) were included, describing 256,033 CEA and 38,605 CAS procedures. For CEA, decreased risk of procedural stroke or death for operations performed by vascular surgeons was found with pooled unadjusted relative risk (RR) of 0.63 (95% confidence interval [CI], 0.46-0.86; seven studies) compared with neurosurgeons and RR of 0.81 (95% CI, 0.66-0.99; six studies) compared with general surgeons. An increased risk of procedural stroke or death for operations performed by neurosurgeons compared with cardiothoracic surgeons was found with a pooled unadjusted RR of 1.22 (95% CI, 1.02-1.46). No studies adjusted for potential confounding, and no significant unadjusted associations were found in other comparisons of operator specialty for the primary outcome. For CAS, no differences in procedural stroke or death were found by operator specialty.

CONCLUSIONS

Studies were at high risk of bias mainly because of potential confounding by patient selection for CEA and CAS. Current evidence is insufficient to restrict CEA or CAS to specific specialties.

High Operator and Hospital Volume Are Associated With a Decreased Risk of Death and Stroke After Carotid Revascularization: A Systematic Review and Meta-analysis

OBJECTIVE

To examine the association between operator or hospital volume and procedural outcomes of carotid revascularization.

BACKGROUND

Operator and hospital volume have been proposed as determinants of outcome after carotid endarterectomy (CEA) or carotid artery stenting (CAS). The magnitude and clinical relevance of this relationship are debated.

METHODS

We systematically searched PubMed and EMBASE until August 21, 2017. The primary outcome was procedural (30 days, in-hospital, or perioperative) death or stroke. Obtained or estimated risk estimates were pooled with a generic inverse variance random-effects model.

RESULTS

We included 87 studies. A decreased risk of death or stroke following CEA was found for high compared to low operator volume with a pooled adjusted odds ratio (OR) of 0.50 (95% confidence interval [CI] 0.28-0.87; 3 cohorts), and a pooled unadjusted relative risk (RR) of 0.59 (95% CI 0.42-0.83; 9 cohorts); for high compared to low hospital volume with a pooled adjusted OR of 0.62 (95% CI 0.42-0.90; 5 cohorts), and a pooled unadjusted RR of 0.68 (95% CI 0.51-0.92; 9 cohorts). A decreased risk of death or stroke after CAS was found for high compared to low operator volume with an adjusted OR of 0.43 (95% CI 0.20-0.95; 1 cohort), and an unadjusted RR of 0.50 (95% CI 0.32-0.79; 1 cohort); for high compared to low hospital volume with an adjusted OR of 0.46 (95% CI 0.26-0.80; 1 cohort), and no significant decreased risk in a pooled unadjusted RR of 0.72 (95% CI 0.49-1.06; 2 cohorts).

CONCLUSIONS

We found a decreased risk of procedural death and stroke after CEA and CAS for high operator and high hospital volume, indicating that aiming for a high volume may help to reduce procedural complications.

REGISTRATION

This systematic review has been registered in the international prospective registry of systematic reviews (PROSPERO): CRD42017051491.

Editor's Choice - Overview of Primary and Secondary Analyses From 20 Randomised Controlled Trials Comparing Carotid Artery Stenting With Carotid Endarterectomy

OBJECTIVES

The aim of this review was to carry out primary and secondary analyses of 20 randomised controlled trials (RCTs) comparing carotid endarterectomy (CEA) with carotid artery stenting (CAS).

METHODS

A systematic review and meta-analysis of data from 20 RCTs (126 publications) was carried out.

RESULTS

Compared with CEA, the 30 day death/stroke rate was significantly higher after CAS in seven RCTs involving 3467 asymptomatic patients (odds ratio [OR] 1.64, 95% confidence interval [CI] 1.02-2.64) and in 10 RCTs involving 5797 symptomatic patients (OR 1.71, 95% CI 1.38-2.11). Excluding procedural risks, late ipsilateral stroke was about 4% at 9 years for both CEA and CAS, i.e., CAS was durable. Reducing procedural death/stroke after CAS may be achieved through better case selection, e.g., performing CEA in (i) symptomatic patients aged > 70 years; (ii) interventions within 14 days of symptom onset; and (iii) situations where stroke risk after CAS is predicted to be higher (segmental/remote plaques, plaque length > 13 mm, heavy burden of white matter lesions [WMLs], where two or more stents might be needed). New WMLs were significantly more common after CAS (52% vs. 17%) and were associated with higher rates of late stroke/transient ischaemic attack (23% vs. 9%), but there was no evidence that new WMLs predisposed towards late cognitive impairment. Restenoses were more common after CAS (10%) but did not increase late ipsilateral stroke. Restenoses (70%-99%) after CEA were associated with a small but significant increase in late ipsilateral stroke (OR 3.87, 95% CI 1.96-7.67; p < .001).

CONCLUSIONS

CAS confers higher rates of 30 day death/stroke than CEA. After 30 days, ipsilateral stroke is virtually identical for CEA and CAS. Key issues to be resolved include the following: (i) Will newer stent technologies and improved cerebral protection allow CAS to be performed < 14 days after symptom onset with risks similar to CEA? (ii) What is the optimal volume of CAS procedures to maintain competency? (iii) How to deliver better risk factor control and best medical treatment? (iv) Is there a role for CEA/CAS in preventing/reversing cognitive impairment?

Comparison of long-term results of carotid endarterectomy for asymptomatic carotid artery stenosis

This article summarizes the current study situation on treatment of asymptomatic carotid artery stenosis and discusses the evidence situation in the literature. The 10-year results of the ACST study have shown that in comparison to conservative treatment, carotid endarterectomy (CEA) has retained a positive long-term effect on the reduction of all forms of stroke. All multicenter randomized controlled trials comparing CEA with carotid artery stenting (CAS) and, in particular the SAPHIRE and CAVATAS studies, have in common that despite a basic evidence level of Ib, the case numbers of asymptomatic patients are too small for a conclusive therapy recommendation. In the overall assessment of the CREST study the resulting difference in the questionable endpoint of “perioperative myocardial infarction” in favor of the CAS methods, could not be confirmed for exclusively asymptomatic patients. In the long-term course of the CREST study, both methods were classified as equivalent, even when the 4‑year results of periprocedural and postprocedural stroke rates in the separate assessment of the asymptomatic study participants clearly favored the CEA. The results of the ACST-1 study showed an equivalent effect of both treatment methods with respect to all investigated endpoints; however, the unequal sizes of the groups in addition to the statistically insufficient case numbers put a question mark on the validity of the study results. The results of the ASCT-2 and CREST-2 studies are to be awaited, which also investigate the significance of “CEA versus CAS” (ASCT-2) and “CEA/CAS + best medical treatment (BMT) versus BMT alone” in only asymptomatic stenoses. The current S3 guidelines allow operative therapy to be considered in patients with a 60–99% asymptomatic carotid artery stenosis, because the risk of stroke is statistically significantly reduced.

Laparoscopic skill assessment of practicing surgeons prior to enrollment in a surgical trial of a new laparoscopic procedure

BACKGROUND

Outcomes of surgical trials hinge on surgeon selection and their underlying expertise. Assessment of expertise is paramount. We investigated whether surgeons' performance measured by the fundamentals of laparoscopic surgery (FLS) assessment program could predict their performance in a surgical trial.

METHODS

As part of a prospective multi-institutional study of minimally invasive inguinal lymphadenectomy (MILND) for melanoma, surgical oncologists with no prior MILND experience underwent pre-trial FLS assessment. Surgeons completed MILND training, began enrolling patients, and submitted videos of each MILND case performed. Videos were scored with the global operative assessment of laparoscopic skills (GOALS) tool. Associations between baseline FLS scores and participant's trial performance metrics were assessed.

RESULTS

Twelve surgeons enrolled patients; their median total baseline FLS score was 332 (range 275-380, max possible 500, passing >270). Participants enrolled 87 patients in the study (median 6 per surgeon, range 1-24), of which 72 (83%) videos were adequate for scoring. Baseline GOALS score was 17.1 (range 9.6-21.2, max possible score 30). Inter-rater reliability was excellent (ICC = 0.85). FLS scores correlated with improved GOALS scores (r = 0.57, p = 0.05) and with decreased operative time (r = -0.6, p = 0.02). No associations were found with the degree of patient recruitment (r = 0.02, p = 0.7), lymph node count (r = 0.01, p = 0.07), conversion rate (r = -0.06, p = 0.38) or major complications(r = -0.14, p = 0.6).

CONCLUSIONS

FLS skill assessment of surgeons prior to their enrollment in a surgical trial is feasible. Although better FLS scores predicted improved operative performance and operative time, other trial outcome measures showed no difference. Our findings have implications for the documentation of laparoscopic expertise of surgeons in practice and may allow more appropriate selection of surgeons to participate in clinical trials.

Angioplasty and stenting for patients with symptomatic intracranial atherosclerosis: study protocol of a randomised controlled trial

INTRODUCTION

Whether adding percutaneous transluminal angioplasty and stenting (PTAS) to background medical treatment is effective for decreasing the incidence of stroke or death in patients with symptomatic intracranial atherosclerosis (ICAS) is still controversial. We perform a randomised controlled trial to examine the effectiveness and safety of an improved PTAS procedure for patients with ICAS.

METHODS AND ANALYSIS

A randomised controlled trial will be conducted in three hospitals in China. Eligible patients with ICAS will be randomly assigned to receive medication treatment (MT) plus PTAS or MT alone. The MT will be initiated immediately after randomisation, while the PTAS will be performed when patients report relief of alarm symptoms defined as sudden weakness or numbness. All patients will be followed up at 30 days, 3 and 12 months after randomisation. The primary end point will be the incidence of stroke or death at 30 days after randomisation. Secondary outcomes will be the incidence of ischaemic stroke in the territory of stenosis arteries, the incidence of in-stent restenosis, the Chinese version of the modified Rankin Scale and the Chinese version of the Stroke-Specific Quality of Life (CSQoL).

ETHICS AND DISSEMINATION

The study protocol is approved by institutional review boards in participating hospitals (reference number FZ20160003, 180PLA20160101 and 476PLA2016007). The results of this study will be disseminated to patients, physicians and policymakers through publication in a peer-reviewed journal or presentations in conferences. It is anticipated that the results of this study will improve the quality of the current PTAS procedure and guide clinical decision-making for patients with ICAS.

TRIAL REGISTRATION NUMBER

NCT02689037.

Carotid Stenting Versus Carotid Endarterectomy: What Did the Carotid Revascularization Endarterectomy Versus Stenting Trial Show and Where Do We Go From Here?

Although rapidly expanding in its use, carotid artery stenting remains a relatively new procedure. Its growth is due, at least in part, to the perceived advantages of a less invasive technique. However, the clinical effectiveness and specific role for stenting in the treatment of carotid occlusive disease are still under evaluation. The primary aim of the randomized clinical trial, Carotid Revascularization Endarterectomy versus Stenting Trial (CREST), was to contrast the relative efficacy of carotid stenting versus carotid endarterectomy in preventing stroke, myocardial infarction, or death during a 30-day periprocedural period or ipsilateral stroke over the follow-up period in patients with symptomatic and asymptomatic extracranial carotid stenosis. The secondary goals were to describe the differential efficacy of the 2 procedures in men and women, contrast periprocedural (30-day) morbidity and postprocedural morbidity and mortality, estimate and contrast the restenosis rates of the 2 procedures, evaluate differences in measures of health-related quality of life and cost-effectiveness, and identify subgroups of participants at differential risk of stenting or surgery. This report summarizes the results obtained from CREST with respect to its primary and secondary aims.

Complication rates and center enrollment volume in the carotid revascularization endarterectomy versus stenting trial

BACKGROUND AND PURPOSE

Evidence indicates that center volume of cases affects outcomes for both carotid endarterectomy and stenting. We evaluated the effect of enrollment volume by site on complication rates in the Carotid Revascularization Endarterectomy Versus Stenting Trial (CREST).

METHODS

The primary composite end point was any stroke, myocardial infarction, or death within 30 days or ipsilateral stroke in follow-up. The 477 approved surgeons performed >12 procedures per year with complication rates <3% for asymptomatic patients and <5% for symptomatic patients; 224 interventionists were certified after a rigorous 2 step credentialing process. CREST centers were divided into tertiles based on the number of patients enrolled into the study, with Group 1 sites enrolling <25 patients, Group 2 sites enrolling 25 to 51 patients, and Group 3 sites enrolling >51 patients. Differences in periprocedural event rates for the primary composite end point and its components were compared using logistic regression adjusting for age, sex, and symptomatic status within site-volume level.

RESULTS

The safety of carotid angioplasty and stenting and carotid endarterectomy did not vary by site-volume during the periprocedural period as indicated by occurrence of the primary end point (P=0.54) or by stroke and death (P=0.87). A trend toward an inverse relationship between center enrollment volume and complications was mitigated by adjustment for known risk factors.

CONCLUSIONS

Complication rates were low in CREST and were not associated with center enrollment volume. The data are consistent with the value of rigorous training and credentialing in trials evaluating endovascular devices and surgical procedures.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00004732.

Picking the good apples: statistics versus good judgment in choosing stent operators for a multicenter clinical trial

BACKGROUND AND PURPOSE

The Carotid Revascularization Endarterectomy Versus Stenting Trial was completed with a low stroke and death rate. A lead-in series of patients receiving carotid artery stenting was used to select the physician-operators for the study, where performance was evaluated by complication rates and by peer review of cases. Herein, we assess the potential contribution of statistical evaluation of complication rates.

METHODS

The ability to discriminate between stent operators who can successfully meet the published guideline of <3% combined rate of stroke and death is calculated under the binomial distribution, based on a small consecutive case series (n=24 patients).

RESULTS

A criterion of ≤2 stroke or death events among the 24 patients (<8% event rate) was required of operators. Setting such a high criterion, however, ensures an inability to exclude operators who cannot meet the criteria. In fact, if a good operator is defined as having a 2% event rate and a poor operator as a 6% event rate, even a series of 240 patients would (on average) still exclude 5.4% of the good operators and include 4.6% of the poor operators.

CONCLUSIONS

The low periprocedural event rates in the trial suggest success in separating skillful operators from less skillful. However, it seems unlikely that statistical assessment of event rates in the lead-in contributed to successful selection, but rather successful selection was more likely because of peer review of subjective and other factors including patient volume and technical approaches.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00004732.

Endarterectomy or carotid artery stenting: the quest continues part two

BACKGROUND

Although randomized trials on carotid artery stenting (CAS) could not establish its equivalence to carotid endarterectomy (CEA) in patients with symptomatic carotid disease, CAS is rapidly evolving. Data on long-term outcome after CAS from randomized trials have now become available and ongoing, prospectively held registries frequently publish their results in increasing numbers of patients. We have therefore reviewed the currently available literature and provide an update of our previous article on this topic.

DATA SOURCES

PubMed literature searches were performed to identify relevant studies regarding current status of CEA and stenting for symptomatic carotid stenosis.

CONCLUSIONS

The efficacy of CAS in patients with symptomatic carotid artery stenosis remains unclear because of varying results in randomized trials. Although multiple registries do report promising results after CAS, peri-interventional stroke/death rates still exceed those rates currently found after CEA. Therefore, CEA remains the "gold standard" in treating these patients.

Endovascular Advances for Extracranial Carotid Stenosis

Carotid artery stenting has become a viable alternative to carotid endarterectomy in the management of carotid stenosis. Over the past 20 years, many trials have attempted to compare both treatment modalities and establish the indications for each one, depending on clinical and anatomic features presented by patients. Concurrently, carotid stenting techniques and devices have evolved and made endovascular management of carotid stenosis safe and effective. Among the most important innovations are devices for distal and proximal embolic protection and new stent designs. This paper reviews these advances in the endovascular management of carotid artery stenosis within the context of the historical background.

Safety of carotid stenting (CAS) is based on institutional training more than individual experience in large-volume centres

BACKGROUND

Operator training is a key factor for the safety of carotid stenting (CAS). Whether institutional practice is associated with improved individual operator outcomes is debated.

OBJECTIVE

To evaluate the effect of the institutional experience on outcomes of new trainees with CAS, a retrospective analysis of a prospectively held database was performed.

METHODS

The overall study period, 2004-2012, was divided into two sequential time frames: 2004-April 2006 (leaders-team phase) and May 2006-2012 (expanded team phase). In the first frame, a single leader-operators team that first approached CAS and passed the original institutional learning curve, performed all the procedures; in the following expanded-team phase, five new trainees joined. Institutional CAS training for new trainees was based on a team-working approach including selection of patients, devices and techniques and collegial meetings with critical review and discussion of all procedural steps and imaging.

RESULTS

A total of 431 CAS procedures were performed in the leaders-team phase and 1026 in the sequential expanded-team phase. Periprocedural complication rates in the two time frames were similar: stroke/death (3.0% vs. 2.1%; P = 0.35), stroke (2.8% vs. 2.1%; P = 0.45) major stroke (0.9% vs. 0.6%, P = 0.49), death (0.2% vs. 0%; P = 0.29) during the leaders-team and expanded-team phase, respectively. However, rates of CAS failure requiring surgical conversions (3.7% vs. 0.8%; P < 0.0001) and mean contrast use (91.6 vs. 71.1 ml; P = 0.0001) decreased in the expanded phase. In the expanded-team frame (May 2006-2012), there was no mortality, and stroke rates were comparable between the leader and new operator teams: 2.6% vs. 1.2%; P = 0.17.

CONCLUSIONS

Institutional experience, including instruction on selection of patients and materials best suited for the procedure, is a primary factor driving outcomes of CAS. An effective team-working approach can reliably improve the training of new trainees preserving CAS safety and efficacy.

Differential outcomes of carotid stenting and endarterectomy performed exclusively by vascular surgeons in the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST)

OBJECTIVE

Outcomes in the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) did not differ between carotid artery stenting (CAS) and carotid endarterectomy (CEA) for the composite primary end point of stroke, myocardial infarction (MI), or death during the periprocedural period or ipsilateral stroke within 4 years. Rigorous credentialing and training of interventionists, including vascular surgeons, were required for the randomization phase of CREST. Because the lead-in phase of CREST had suggested higher perioperative risks after CAS performed by vascular surgeons, the purpose of this analysis was to examine differences in outcomes after randomization between CAS and CEA performed by vascular surgeons.

METHODS

CREST is a prospective randomized controlled trial with blinded end point adjudication. Vascular surgeons performed 237 (21%) of the CAS procedures and 765 (65%) of the CEA procedures among 2320 patients who received their assigned treatment. Proportional hazards analyses were used to estimate the relative efficacy of CAS vs CEA for the composite primary end point and also for stroke and death.

RESULTS

Among 2502 randomized patients, 1321 (53%) were symptomatic and 1181 (47%) were asymptomatic. For procedures performed exclusively by vascular surgeons, the primary end point did not differ between CAS and CEA at 4-year follow-up (6.2% vs 5.6%, respectively; hazard ratio [HR], 1.30; 95% confidence interval [CI], 0.70-2.41; P = .41) In this subgroup, the periprocedural stroke and death rates were higher after CAS than CEA for symptomatic patients (6.1% vs 1.3%; P = .01). Asymptomatic patients also had slightly higher stroke and death rates after CAS (2.6% vs 1.1%; P = .20), although this difference did not reach statistical significance. Conversely, cranial nerve injuries (0.0% vs 5.0%; P < .001) were less frequent after CAS than CEA. The MI rates were slightly lower after CAS (1.3% vs 2.6%; P = .24). In performing CAS, vascular surgeons had outcomes for the periprocedural primary end point comparable to the outcomes of all interventionists (HR, 0.99; 95% CI, 0.50-2.00) after adjusting for age, sex, and symptomatic status. Vascular surgeons also had similar results after CEA for the periprocedural primary end point compared with other surgeons (HR, 0.73; 95% CI, 0.42-1.27).

CONCLUSIONS

When performed by surgeons, CAS and CEA have similar net outcomes, although the periprocedural risks vary (lower stroke with CEA and lower MI with CAS). These data suggest that appropriately trained vascular surgeons may safely offer both CEA and CAS for the prevention of stroke. The remarkably low stroke and death rates after CEA performed by vascular surgeons in CREST, particularly among symptomatic patients, represent the best outcomes ever reported after carotid interventions from a randomized controlled trial. ClinicalTrials.gov identifier: NCT0000473.

Interventional radiology at the meetings of the German Radiological Society from 1998 to 2008: evaluation of structural changes and radiation issues

OBJECTIVES

Evaluation of structural changes and the weight given to radiation exposure of interventional radiology (IR) contributions at the Congress of the German Radiological Association from 1998 to 2008.

METHODS

All IR abstracts were evaluated for type of contribution, design, imaging modality, and anatomic region. Weight given to radiation exposure was recorded as general statement, main topic and/or dose reduction. Statistical analysis included calculation of absolute/relative proportions of subgroups and ANOVA regression analyses.

RESULTS

Out of 9,436 abstracts, 1,728 (18%) were IR-related. IR abstracts significantly rose to a maximum of 200 (20%) in 2005 (P = 0.048). While absolute numbers of scientific contributions declined, educational contributions significantly increased (P = 0.003). Computed tomography (CT) and magnetic resonance imaging (MRI) were the main IR imaging modalities, with growing use of CT (P = 0.021). The main body regions were vessels (45%) and abdomen (31%). Radiation exposure was addressed as a general statement in 3% of abstracts, as a main topic in 2%, and for dose reduction in 1%, respectively. During the study interval a significant growth of dose reduction abstracts was observed (P = 0.016).

CONCLUSIONS

IR emerged as a growing specialty of radiology, with a significant increase in educational contributions. Radiation exposure was rarely in the focus of interest but contributions relating to dose reduction demonstrated a significant growth during the study period. Main Messages • Interventional radiology emerged as a growing specialty at the German radiological congress. • Significant increments of educational and prospective research contributions could be observed. • Despite a significant trend towards computed tomography, radiation exposure of IR was rarely in the focus of interest. • Contributions related to dose reduction demonstrated a significant growth during the study period.

Defining the type of surgeon volume that influences the outcomes for open abdominal aortic aneurysm repair

OBJECTIVE

Prior studies have reported improved clinical outcomes with higher surgeon volume, which is assumed to be a product of the surgeon's experience with the index operation. We hypothesized that composite surgeon volume is an important determinant of outcome. We tested this hypothesis by comparing the impact of operation-specific surgeon volume versus composite surgeon volume on surgical outcomes, using open abdominal aortic aneurysm (AAA) repair as the index operation.

METHODS

The Nationwide Inpatient Sample was analyzed to identify patients undergoing open AAA repairs for 2000 to 2008. Surgeons were stratified into deciles based on annual volume of open AAA repairs ("operation-specific volume") and overall volume of open vascular operations ("composite volume"). Composite volume was defined by the sum of several open vascular operations: carotid endarterectomy, aortobifemoral bypass, femoral-popliteal bypass, and femoral-tibial bypass. Multiple logistic regression analyses were used to examine the relationship between surgeon volume and in-hospital mortality for open AAA repair, adjusting for both patient and hospital characteristics.

RESULTS

Between 2000 and 2008, an estimated 111,533 (95% confidence interval [CI], 102,296-121,232) elective open AAA repairs were performed nationwide by 6,857 surgeons. The crude in-hospital mortality rate over the study period was 6.1% (95% CI, 5.6%-6.5%). The mean number of open AAA repairs performed annually was 2.4 operations per surgeon. The mean composite volume was 5.3 operations annually. As expected, in-hospital mortality for open AAA repair decreased with increasing volume of open AAA repairs performed by a surgeon. Mortality rates for the lowest and highest deciles of surgeon volume were 10.2% and 4.5%, respectively (P < .0001). A similar pattern was observed for composite surgeon volume, as the mortality rates for the lowest and highest deciles of composite volume were 9.8% and 4.8%, respectively (P < .0001). After adjusting for patient and hospital characteristics, increasing composite surgeon volume remained a significant predictor of lower in-hospital mortality for open AAA repair (odds ratio, 0.994; 95% CI, .992-.996; P < .0001), whereas increasing volume of AAA repairs per surgeon did not predict in-hospital deaths.

CONCLUSIONS

The current study suggests that composite surgeon volume-not operation-specific volume-is a key determinant of in-hospital mortality for open AAA repair. This finding needs to be considered for future credentialing of surgeons.

Carotid artery stenting: rationale, technique, and current concepts

Carotid stenosis is a major risk factor for stroke. With the aging of the general population and the availability of non-invasive vascular imaging studies, the diagnosis of a carotid plaque is commonly made in medical practice. Asymptomatic and symptomatic carotid stenoses need to be considered separately because their natural history is different. Two large randomized controlled trials (RCTs) showed the effectiveness of carotid endarterectomy (CEA) in preventing ipsilateral ischemic events in patients with symptomatic severe stenosis. The benefit of surgery is much less for moderate stenosis and harmful in patients with stenosis less than 50%. Surgery has a marginal benefit in patients with asymptomatic stenosis. Improvements in medical treatment must be taken into consideration when interpreting the results of these previous trials which compared surgery against medical treatment available at the time the trials were conducted. Carotid artery stenting (CAS) might avoid the risks associated with surgery, including cranial nerve palsy, myocardial infarction, or pulmonary embolism. Therefore and additionally to well-established indications of CAS, this endovascular approach might be a valid alternative particularly in patients at high surgical risk. However, trials of endovascular treatment of carotid stenosis have failed to provide enough evidence to justify routine CAS as an alternative to CEA in patients suitable for surgery. More data from ongoing randomized trials of CEA versus CAS will be soon available. These results will help determining the role of CAS in the management of patients with carotid artery stenosis.

Carotid Artery Stenting in the Nation: The Influence of Hospital and Physician Volume on Outcomes

Objectives: To assess national outcomes of carotid artery stenting (CAS) with respect to hospital and practitioner volume.

Methods: The 2005 to 2006 Nationwide Inpatient Sample (NIS) was used to assess CAS with respect to hospital volume, physician volume, and associated complications. Results: Eighteen thousand five hundred ninety-nine CAS interventions were identified. The top 25% was used to define high-volume hospitals (>60 CAS/2 years) and practitioners (>30 CAS/2 years). The stroke rate after CAS was significantly different between low- and high-volume hospitals (2.35% vs 1.78%, respectively; P = .0206). The stroke rate after CAS was also significantly different between low- and high-volume practitioners (2.19% vs 1.51%, P = .0243). Hospital resource use varied significantly between low- and high-volume hospitals (length of stay [LOS]: 1.64 ± 2.10 vs 1.45 ± 11.21, P = .0006; total charges: $32 261 ± 20 562 vs $30 131 ± 19 592, P = .0047) and practitioners (LOS: 1.70 ± 2.14 vs 1.36 ± 1.36; P < .0001; total charges: $33 762 ± 21 081 vs $23 957 ± 19 713; P < .0001). Conclusions: This analysis demonstrates that hospital and physician volume are associated with outcomes and utilization after CAS. High-volume hospitals and practitioners were associated with lower procedure stroke rates and decreased hospital resource utilization.

Reporting standards for angioplasty and stent-assisted angioplasty for intracranial atherosclerosis

BACKGROUND AND PURPOSE

Intracranial cerebral atherosclerosis causes ischemic stroke in a significant number of patients. Technological advances over the past 10 years have enabled endovascular treatment of intracranial atherosclerotic stenosis. The number of patients treated with angioplasty or stent-assisted angioplasty for this condition is increasing. Given the lack of universally accepted definitions, the goal of this document is to provide consensus recommendations for reporting standards, terminology, and written definitions when reporting clinical and radiological evaluation, technique, and outcome of endovascular treatment using angioplasty or stent-assisted angioplasty for stenotic and occlusive intracranial atherosclerosis.

SUMMARY OF REPORT

This article was written under the auspices of Joint Writing Group of the Technology Assessment Committee, Society of NeuroInterventional Surgery, Society of Interventional Radiology; Joint Section on Cerebrovascular Neurosurgery of the American Association of Neurological Surgeons and Congress of Neurological Surgeons; and the Section of Stroke and Interventional Neurology of the American Academy of Neurology. A computerized search of the National Library of Medicine database of literature (PubMed) from January 1997 to December 2007 was conducted with the goal to identify published endovascular cerebrovascular interventional data in stenotic intracranial atherosclerosis that could be used as benchmarks for quality assessment. We sought to identify those risk adjustment variables that affect the likelihood of success and complications. This document offers the rationale for different clinical and technical considerations that may be important during the design of clinical trials for endovascular treatment of intracranial stenotic and occlusive atherosclerosis. Included in this guidance document are suggestions for uniform reporting standards for such trials. These definitions and standards are primarily intended for research purposes; however, they should also be helpful in clinical practice and applicable to all publications.

CONCLUSION

In summary, the definitions proposed represent recommendations for constructing useful research data sets. The intent is to facilitate production of scientifically rigorous results capable of reliable comparisons between and among similar studies. In some cases, the definitions contained here are recommended by consensus of a panel of experts in this writing group for consistency in reporting and publication. These definitions should allow different groups to publish results that are directly comparable.

Carotid artery stenting: Impact of practitioner specialty and volume on outcomes and resource utilization

OBJECTIVES

A variety of endovascular specialists perform carotid artery stenting (CAS), but little data exist on outcomes and resource utilization among these specialists. We analyzed differences in outcomes after CAS was performed by radiologists (RAD), cardiologists (CRD), and vascular surgeons (VAS).

METHODS

Secondary data analysis of the 2005-2006 State Inpatient Databases for New Jersey were analyzed. Patients with elective admission to the hospital who had CAS procedure <or=2 days after admission were identified. CAS outcomes were analyzed with respect to practitioner specialty and volume, associated complications, and hospital resource utilization.

RESULTS

We identified 625 CAS cases. CRD performed 378 (60.5%), VAS, 199 (31.8%); and RAD, 48 (7.7%). The overall stroke rate was 2.72% and by specialty was CRD, 3.17%; VAS, 2.01%, and RAD, 2.08% (P = .6880). The overall cardiac complication rate was 2.40% (CRD, 2.12%; VAS, 3.02%; RAD, 2.08%; P = .7899). Renal and pulmonary complications were low (0.64% and 0.32%, respectively). Mean hospital length of stay (LOS) in days was significantly shorter for VAS (1.64 +/- 1.40) compared with RAD (2.83 +/- 5.15; P = .0167) and had the same trend compared with CRD (2.14 +/- 3.37; P = .0649). Intensive care unit (ICU) LOS was shorter for VAS (0.52 +/- 0.97) and CRD (0.30 +/- 0.71) than for RAD (2.12 +/- 4.48; P < .0001). The mean total hospital cost was significantly greater for RAD ($20,987 +/- $26,603) and CRD ($18,182 +/- $16,364) than for VAS ($10,000 +/- $4947; P = .0011 and P < .0001, respectively). ICU cost for RAD ($5963 +/- $14,551) was also more than for VAS ($864 +/- $1514; P < .0001) and CRD ($473 +/- $1561; P < .0001). Medical supply costs were significantly greater for CRD ($8772 +/- $9546) than for VAS ($3354 +/- $2261; P < .0001) and RAD ($4964 +/- $2595; P = .0142). Total hospital cost, LOS, and medical supplies were significantly lower for high-volume practitioners vs low-volume practitioners (P < .0001).

CONCLUSION

Stroke rates after CAS did not vary significantly among practitioner specialties. Hospital resource utilization did vary significantly: Vascular surgeons had the lowest utilization of hospital resources for performing CAS. High practitioner volume was associated with lower hospital resource utilization. Elucidation of factors creating resource utilization disparities among endovascular practitioners may lead to improved patient outcomes and permit significant future cost savings for carotid interventions.

Reporting Standards for Angioplasty and Stent-Assisted Angioplasty for Intracranial Atherosclerosis

Background and Purpose— Intracranial cerebral atherosclerosis causes ischemic stroke in a significant number of patients. Technological advances over the past 10 years have enabled endovascular treatment of intracranial atherosclerotic stenosis. The number of patients treated with angioplasty or stent-assisted angioplasty for this condition is increasing. Given the lack of universally accepted definitions, the goal of this document is to provide consensus recommendations for reporting standards, terminology, and written definitions when reporting clinical and radiological evaluation, technique, and outcome of endovascular treatment using angioplasty or stent-assisted angioplasty for stenotic and occlusive intracranial atherosclerosis.

Summary of Report— This article was written under the auspices of Joint Writing Group of the Technology Assessment Committee, Society of NeuroInterventional Surgery, Society of Interventional Radiology; Joint Section on Cerebrovascular Neurosurgery of the American Association of Neurological Surgeons and Congress of Neurological Surgeons; and the Section of Stroke and Interventional Neurology of the American Academy of Neurology. A computerized search of the National Library of Medicine database of literature (PubMed) from January 1997 to December 2007 was conducted with the goal to identify published endovascular cerebrovascular interventional data in stenotic intracranial atherosclerosis that could be used as benchmarks for quality assessment. We sought to identify those risk adjustment variables that affect the likelihood of success and complications. This document offers the rationale for different clinical and technical considerations that may be important during the design of clinical trials for endovascular treatment of intracranial stenotic and occlusive atherosclerosis. Included in this guidance document are suggestions for uniform reporting standards for such trials. These definitions and standards are primarily intended for research purposes; however, they should also be helpful in clinical practice and applicable to all publications.

Conclusion— In summary, the definitions proposed represent recommendations for constructing useful research data sets. The intent is to facilitate production of scientifically rigorous results capable of reliable comparisons between and among similar studies. In some cases, the definitions contained here are recommended by consensus of a panel of experts in this writing group for consistency in reporting and publication. These definitions should allow different groups to publish results that are directly comparable.

Does sex matter? Thirty-day stroke and death rates after carotid artery stenting in women versus men: results from the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) lead-in phase

BACKGROUND AND PURPOSE

Several carotid endarterectomy randomized, controlled trials and series have reported higher perioperative stroke and death rates for women compared with men. The potential for this same relationship with carotid artery stenting was examined in the lead-in phase of the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST).

METHODS

CREST compares efficacy of carotid endarterectomy and carotid artery stenting in preventing stroke, myocardial infarction, and death in the periprocedural period and ipsilateral stroke over the follow-up period. CREST included a "lead-in" phase of symptomatic (>or=50% stenosis) and asymptomatic (>or=70% stenosis) patients. Patients were examined by a neurologist preprocedure, at 24 hours, and at 30 days. Review of stroke and death was by an independent events committee. The association of sex with periprocedural stroke and death was examined in 1564 patients undergoing carotid artery stenting (26.5% symptomatic).

RESULTS

Women comprised 37% of the lead-in cohort and did not differ from men by age, symptomatic status, or characteristics of the internal carotid artery. The 30-day stroke and death rate for women was 4.5% (26 of 579; 95% CI, 3.0% to 6.5%) compared with 4.2% (41 of 985; 95% CI, 3.0% to 5.6%) for men. The difference in stroke and death rate was not significant nor were there any significant differences by sex after adjustment for age, arterial characteristics, or cardiovascular risk factors.

CONCLUSIONS

These results do not provide evidence that women have a higher carotid artery stenting stroke and death rate compared with men. The potential differential periprocedural risk by sex will be prospectively addressed in the randomized phase of CREST.

Stent implantation of multichanneled pseudoocclusion of the internal carotid artery

Multichanneled pseudoocclusion (MCPO) is a severe stenosis with more than 95% of the carotid bulb with multichannels in the stenotic segment. This report describes successful carotid stent implantation in five patients with MCPO of the internal carotid artery. Probing of the micro-guide wire through the channel with support of the microcatheter made subsequent angioplasty and stent placement possible without procedure-related complications. There was neither additional stroke nor restenosis during a follow-up period of 6-54 months.

Carotid artery stenting versus carotid endarterectomy: current status

Carotid occlusive disease remains an important cause of ischemic stroke. The results of large, randomized, clinical trials have established the benefit of surgical revascularization in patients with symptomatic or asymptomatic carotid stenosis. The introduction of balloon angioplasty and stenting of the extracranial carotid artery as a potential alternative to surgery has been received with enthusiasm by patients and physicians. Whether or not this enthusiasm is justified fully has yet to be determined. This article reviews established and emerging data from clinical trials evaluating the safety and efficacy of carotid endarterectomy, carotid angioplasty, and stenting.