CREST and CARESS to Evaluate Carotid Stenting: Time to Get to Work!

Carotid arterial stent implantation follow-up and results in 50 patients: preliminary report

Background

Carotid artery stenting (CAS) is considered as a safe and effective procedure for treatment of carotid artery stenosis. Evaluation of this procedure’s complications is essential for proper clinical decision-making.

Objective

This study aimed to evaluate the cardiovascular events after CAS among our patients in Isfahan, Iran.

Methods

This case-series study was conducted on fifty patients from December 2013 to May 2016. These patients were referred to the cardiology centers of Isfahan, Iran by a neurologist, for stenting of extracranial carotid arteries. The second step was examining the patients by cardiac interventionist. Stenting was performed on symptomatic patients with carotid artery stenosis of more than 50 percent or asymptomatic patients with more than 70 percent carotid artery stenosis on Doppler ultrasonography. Neurologic evaluation was performed at baseline, during hospital stay, and follow-up. Transient ischemic attack (TIA)/Stroke and Myocardial infarction (MI) questionnaires were filled out by a cardiologist over telephone interviews with the patients, for follow-up of one month, six months and at the end of study. Carotid Doppler ultrasonography was performed before and 6 months after stenting for evaluation of restenosis. Indeed, during the follow-up study, the major adverse cardiac events (MACE) were evaluated. All data were analyzed through SPSS v.17.

Results

The mean age of patients was 70.73 (±14.01) years old (range: 48–89 years old). Composite endpoint of death, stroke, and MI was totally 8 percent. The rate of carotid arterial restenosis (Luminal arterial narrowing>50%) was 8%.

Conclusions

Despite the fact that carotid stenting is new in our center, our results can be compared to other important studies.

What Should We Do with Asymptomatic Carotid Stenosis?

The benefit of prophylactic carotid endarterectomy (CEA) for patients with asymptomatic severe carotid stenosis in the major randomised surgical studies was small, expensive and may now be absorbed by improvements in best practice medical intervention. Strategies to identify patients with high stroke risk are needed. If surgical intervention is to be considered the complication rates of individual surgeons should be available. Clinicians will differ in their interpretation of the same published data. Maintaining professional relationships with clinicians from different disciplines often involves compromise. As such, the management of a patient will, in part, depend on what kind of specialist the patient is referred to. The clinician's discussion with patients about this complex issue must be flexible to accommodate differing patient expectations. Ideally, patients prepared to undergo surgical procedures should be monitored in a trial setting or as part of an audited review process to increase our understanding of current practice outcomes.

Asymptomatic carotid artery stenosis

Severe asymptomatic carotid stenosis is associated with a stroke risk of approximately 2% per annum. Aggressive management of risk factors is recommended, including cessation of smoking, and treatment of hypertension, diabetes, and hypercholesterolemia. Patients should be treated with antiplatelet agents. Carotid endarterectomy (CEA) in patients with greater than or equal to 60% stenosis reduces the risk of stroke by approximately 1% per annum overall. The benefit is greatest for men and younger patients. There may be no benefit for women or for older patients. Carotid angioplasty and stenting is not recommended as an alternative to CEA until there is clinical trial evidence of efficacy in asymptomatic stenosis, except in some patients with technical contraindications to CEA. There is no evidence that patients with asymptomatic severe carotid stenosis should undergo carotid revascularization prior to other surgical procedures, including coronary bypass surgery.

Carotid revascularization using endarterectomy or stenting systems (CaRESS): 4-year outcomes

PURPOSE

To examine the 4-year outcomes from Carotid Revascularization using Endarterectomy or Stenting Systems (CaRESS) in light of the current reimbursement guidelines for carotid artery stenting (CAS) from the Centers for Medicare and Medicaid Services (CMS).

METHODS

CaRESS was designed as a prospective, nonrandomized comparative cohort study of a broad-risk population of symptomatic and asymptomatic patients with carotid stenosis. In all, 397 patients (247 men; mean age 71 years, range 43-89) were enrolled and underwent carotid endarterectomy (CEA; n = 254) or protected CAS (n = 143). More than 90% of patients had >75% stenosis; two thirds were asymptomatic. The primary endpoints included (1) all-cause mortality, (2) any stroke, and (3) myocardial infarction (MI), as well as the composite endpoints of (4) death and any nonfatal stroke and (5) death, nonfatal stroke, and MI. The secondary endpoints were restenosis, repeat angiography, and carotid revascularization. All patients were classified with respect to surgical risk, symptom status, and stenosis grade based on criteria published by the CMS. In addition, separate analyses were performed comparing genders and octogenarians to those <80 years old.

RESULTS

No significant differences in the primary outcome measures were found between the CEA and CAS groups in the 4-year analysis. The incidences of any stroke at 4 years were 9.6% for CEA and 8.6% for CAS (p = 0.444); when combined with death, the composite death/nonfatal stroke rates were 26.5% for CEA versus 21.8% for CAS (p = 0.361). The composite endpoint of death, nonfatal stroke, and MI at 4 years was 27.0% in CEA versus 21.7% in CAS (p = 0.273) patients. The secondary endpoints of restenosis (p = 0.014) and repeat angiography (p = 0.052) were higher in the CAS arm. There were no differences in any of the subgroups stratified according the CMS guidelines or in the gender comparison. Four-year incidences of death/nonfatal stroke and death/nonfatal stroke/MI were higher in the CEA arm among patients <80 years of age (p = 0.049 and p = 0.030, respectively). There were no significant differences between these incidences in the octogenarian subgroup.

CONCLUSION

The risk of death or nonfatal stroke 4 years following CAS with distal protection is equivalent to CEA in a broad category of patients with carotid stenosis. There were no significant differences in stroke or mortality rates between high-risk and non-high-risk patients and no differences in outcomes between symptomatic and asymptomatic patients. After 4 years, CAS had a 2-fold higher restenosis rate compared to CEA. The risk of death/stroke or death/stroke/MI appears to be higher following CEA than CAS among patients <80 years of age, yet there is no statistically significant relationship between death, stroke, or MI among octogenarians.

Impact of Diabetes, Patient Age, and Gender on the 30-Day Incidence of Stroke and Death in Patients Undergoing Carotid Artery Stenting with Embolus Protection: A Post-Hoc Subanalysis of a Prospective Multicenter Registry

PURPOSE

To assess the impact of diabetes, patient age, and gender on major periprocedural (30-day) complications (major and minor strokes, all-cause deaths) following carotid artery stenting (CAS).

METHODS

An exploratory analysis was performed of 695 patients (516 men; mean age 69.9+/-8.4 years) enrolled consecutively between September 1999 and September 2002 in a multicenter Italian/German registry of routine CAS using cerebral protection devices. There were 535 nondiabetic patients and 160 diabetic patients in the analysis.

RESULTS

Logistic regression analysis revealed that diabetes and age, but not gender, impacted the cumulative 30-day incidence of any stroke and death (OR 2.1, 95% CI 1.0 to 4.8, p = 0.068 and OR 1.06, 95% CI 1.01 to 1.12, p = 0.031, respectively), as well as the 30-day incidence of major strokes and deaths (OR 5.9, 95% CI 1.6 to 21.8, p = 0.007 and OR 1.13, 95% CI 1.02 to 1.25, p = 0.018, respectively). According to receiver-operating characteristic analysis, age had no discriminatory power to predict complications in nondiabetic patients, but an age of 75 years was identified as the optimal cut point to predict complications in diabetic patients. Compared with nondiabetic patients, diabetics > or =75 years had a 4.3 greater risk of experiencing any stroke or death (95% CI 1.3 to 12.3, p = 0.016) and a 12.0 greater risk of a major stroke or death (95% CI 2.1 to 66.5, p = 0.005). Diabetics <75 years had no increase in risk over that of nondiabetic patients.

CONCLUSION

Diabetic patients > or =75 years carry a significantly increased risk for strokes or death after protected CAS. The findings should be taken into consideration when treating elderly diabetic patients.

Use of computer simulation for determining endovascular skill levels in a carotid stenting model

OBJECTIVES

The purpose of this study was to determine whether performance on a simulator model of carotid artery stenting correlates with previous endovascular experience and to assess the effects of repetition and training.

METHODS

Participants were stratified to untrained and advanced skill groups on the basis of number of endovascular procedures previously performed. Baseline performance was assessed by means of a pretest, and participants were randomized to practice and no-practice groups. Practice consisted of a 30-minute to 60-minute proctored session before taking a final test; those in the no-practice group proceeded directly to the final test without this session. Primary outcomes were completion of a standardized protocol and the length of time needed to complete all steps.

RESULTS

Twenty-nine subjects (16 untrained, 13 advanced) participated fully in the study. Ninety-two percent of participants in the advanced group successfully completed the pretest, versus 63% in the untrained group (P = .09); mean time to successful completion was 29.9 +/- 4.8 (mean +/- SD) versus 48.0 +/- 9.9 minutes, respectively (P < .001). Subjects who received no practice did not significantly improve their completion times between pretest and final test, whereas those who received practice did (novice, 47.9 +/- 7.0 minutes vs 24.5 +/- 2.9 minutes, P < .001; advanced, 29.6 +/- 3.1 minutes vs 20.2 +/- 4.1 minutes, P < .001). The group without previous training had significantly more time improvement from training than did the advanced group. Exit survey results showed that those who had the opportunity to practice more commonly believed that the simulator increased their endovascular skills and interest in vascular surgery (both P < .01 vs untrained group).

CONCLUSIONS

Performance on the carotid stenting simulator correlated with previous endovascular experience. Although both novice and advanced groups improved their time after a 30-minute to 60-minute proctored training session, improvement in the novice group was greater than that in the advanced group, which suggests that novices may benefit disproportionately from this type of training.

Carotid Plaque Echolucency Increases the Risk of Stroke in Carotid Stenting

Background— Carotid artery stenting (CAS) has recently emerged as a potential alternative to carotid endarterectomy. Cerebral embolization is the most devastating complication of CAS, and the echogenicity of carotid plaque has been indicated as one of the risk factors involved. This is the first study to analyze the role of a computer-assisted highly reproducible index of echogenicity, namely the gray-scale median (GSM), on the risk of stroke during CAS.

Methods and Results— The Imaging in Carotid Angioplasty and Risk of Stroke (ICAROS) registry included 418 cases of CAS collected from 11 international centers. An echographic evaluation of carotid plaque with GSM measurement was made preprocedurally. The onset of neurological deficits during the procedure and the postprocedural period was recorded. The overall rate of neurological complications was 3.6%: minor strokes, 2.2%, and major stroke, 1.4%. There were 11 of 155 strokes (7.1%) in patients with GSM ≤25 and 4 of 263 (1.5%) in patients with GSM >25 ( P =0.005). Patients with severe stenosis (≥85%) had a higher rate of stroke ( P =0.03). The effectiveness of brain protection devices was confirmed in those with GSM >25 ( P =0.01) but not in those with GSM ≤25. Multivariate analysis revealed that GSM (OR, 7.11; P =0.002) and rate of stenosis (OR, 5.76; P =0.010) are independent predictors of stroke.

Conclusions— Carotid plaque echolucency, as measured by GSM ≤25, increases the risk of stroke in CAS. The inclusion of echolucency measured as GSM in the planning of any endovascular procedure of carotid lesions allows stratification of patients at different risks of complications in CAS.

Modulating thrombotic potential in catheter-based percutaneous coronary and peripheral vascular interventions

Thrombosis is an obligatory consequence of all percutaneous vascular interventions. Balloon angioplasty, intravascular stents and other devices routinely used to facilitate dilatation of critical vascular stenoses result in fracture of the intima and exposure of the thrombogenic subendothelium with initiation and perpetuation of platelet activation and aggregation. This not uncommonly results in thrombus formation that may lead to abrupt vessel closure, distal ischemia and tissue infarction, and target organ dysfunction. Fortunately, advances in our understanding of the mechanisms that underlie vascular thrombosis have led to advances in the use of adjunctive pharmacological agents that modulate this pathophysiological response and have led to important reductions in the incidence and severity of thrombotic complications of percutaneous transluminal interventions.

Evolution of Neuroendovascular Intervention: A Review of Advancement in Device Technology

NEUROENDOVASCULAR SURGERY IS a rapidly evolving field. Each year, numerous improvements are made in the endovascular surgeon's armamentarium. This evolution in technology, which is occurring at a dizzying pace, addresses many of the current limitations of neuroendovascular approaches. The potential to improve the outcomes of our patients is tremendous, particularly because one of the most common and most devastating neurological disorders, ischemic stroke, remains largely untreated. This article presents several of the new technologies that are currently being investigated or are under development and have the potential to lead to major advances in endovascular approaches for the treatment of intracranial and extracranial diseases.

Approaches to difficult filter retrieval in carotid stenting

The treatment of carotid disease continues to evolve with an increasing number of the lesions being successfully treated percutaneously. A large part of the success of percutaneous therapy has resulted from the use of distal protection devices and their ability to reduce embolization and subsequent strokes. However, device retrieval through implanted stents can be problematic. We describe situations in which difficulty was encountered advancing the distal protection filter retrieval device through the stent, as well as the different approaches to solve this potential problem.

Unprotected carotid artery stenting compared to carotid endarterectomy in a community setting

PURPOSE

To evaluate the feasibility and safety of carotid artery stenting (CAS) performed by a dedicated multidisciplinary team in a community hospital.

METHODS

Forty-nine patients (30 men; mean age 74.3 +/- 7.4 years, range 51-88) with 14 symptomatic and 35 asymptomatic >50% carotid stenoses were enrolled into the study and treated with self-expanding stents without cerebral protection. The patients were evaluated at 30 days for death, neurological sequelae, and length of stay. A contemporaneous group of 140 patients (80 men; mean age 72.3 +/- 7.7 years, range 43-89) undergoing carotid endarterectomy (CEA) was used for comparison of the outcome measures. Owing to crossover of failed CAS patients to the CEA group, the data were analyzed according to intention-to-treat and treatment-received.

RESULTS

The only difference in baseline characteristics between the treatment and control groups was the greater frequency of bilateral disease in the CEA group (p=0.009). The CAS procedures were successful in 47 (96.0%) patients; 2 access failures were converted to endarterectomy, and 1 access-site pseudoaneurysm was treated surgically. There were no deaths or myocardial infarctions in either group. In the CAS group, there were no major and only 2 (4.1%) minor strokes compared to 4 (2.9%) major and 4 (2.9%) minor strokes in the CEA group (p>0.05). Median LOS was significantly lower in the CAS group (p<0.0001).

CONCLUSIONS

Careful case selection and multidisciplinary collaboration facilitate the safe performance of carotid stenting in a community setting with acceptable early results.

Carotid Stent-Assisted Angioplasty: The Newest Addition to the Surgeons' Armamentarium in the Management of Carotid Occlusive Disease

Carotid artery angioplasty and stenting (CAS) has been accomplished in multiple centers with short-term and midterm results similar to carotid endarterectomy (CEA). Until completion of multicentered prospective evaluation of the benefit of CAS versus established therapy (CEA) clinical judgment must be used to determine whether an individual patient with unusual technical challenges and/or risks might be best suited for CEA or CAS. We report our experience with 41 CAS procedures in 39 patients treated from November 1996 through November 2001. Six patients had primary lesions (three symptomatic and three asymptomatic). Thirty-three patients had 35 procedures for recurrent carotid stenosis (11 symptomatic and 24 asymptomatic). Technical success was achieved in 40 of 41 procedures. No deaths occurred. The 30-day major stroke rate was one in 41 (2.4%), and the overall 30-day stroke/transient ischemic attack rate was three in 41 (7.3%). No recurrence or late neurologic events were seen in patients treated for primary carotid stenosis. A 23 per cent recurrence rate was observed in patients treated for recurrent carotid stenosis, after one or more CEAs, with mean follow-up of 18 ± 14 months. Recurrence requiring operative correction with carotid resection and interposition grafts occurred in three patients treated with CAS in this group. Late deaths occurred in six patients; one of these was due to stroke. Overall freedom from late stroke and/or need for reintervention (by Kaplan-Meier analysis) was 64 ± 13 per cent at 48 months in the group treated by CAS for post-CEA recurrence. CAS represents a technically simplistic means of providing carotid revascularization. However, its role remains undefined and benefits unproven. Surgical revascularization remains appropriate for patients with operable carotid lesions. However, surgical revascularization is not always an ideal option when we are faced with difficult carotid lesions and risks. For this reason we advocate that all surgeons who intend to remain specialists in the management of carotid disease should attain, master, and maintain the skills necessary for CAS.

Multicenter evaluation of carotid artery stenting with a filter protection system

OBJECTIVES

The aim of this study was to evaluate the feasibility and safety of carotid artery stenting (CAS) with a filter protection system.

BACKGROUND

Neurologic events linked to the embolization of particulate matter to the cerebral circulation may complicate CAS. Strategies designed to capture embolic particles during carotid intervention are being evaluated for their efficacy in reducing the risk of these events.

METHODS

Between September 1999 and July 2001, a total of 162 patients (164 hemispheres) underwent CAS with filter protection (NeuroShield, MedNova Ltd., Galway, Ireland) according to prospective protocols evaluating the filter system at three institutions.

RESULTS

Angiographic success was achieved in 162 of the procedures (99%) and filter placement was successful in 154 (94%) procedures. Carotid access was unsuccessful in two cases (1%) and filter placement in eight cases (5%). Of the latter, five procedures were completed with no protection and three were completed using alternative protection devices. On an intention-to-treat basis, the overall combined 30-day rate of all-stroke and death was 2% (four events: two minor strokes and two deaths). This includes one minor stroke in a patient with failed filter placement and CAS completed without protection. There was one cardiac arrhythmic death and one death from hyperperfusion-related intracerebral hemorrhage. There were no major embolic strokes.

CONCLUSIONS

Carotid artery stenting with filter protection is technically feasible and safe. Early clinical outcomes appear to be favorable and need to be confirmed in a larger comparative study.