In-stent Restenosis After Carotid Angioplasty and Stenting: A Challenge for the Vascular Surgeon

Outcomes Following Carotid Revascularization in Patients with Prior Ipsilateral Carotid Artery Stenting in the Vascular Quality Initiative

OBJECTIVES

The outcomes of carotid revascularization in patients with prior carotid artery stenting remain understudied. Prior research has not reported the outcomes after Transcarotid artery revascularization (TCAR) in patients with previous carotid artery stenting. In this study, we compared the peri-operative outcomes of TCAR, tfCAS and CEA in patients with prior ipsilateral CAS using the VQI.

METHODS

Using the Vascular Quality Initiative data from 2016 to 2023, we identified patients who underwent TCAR, tfCAS, or CEA following prior ipsilateral carotid artery stenting. We included covariates such as age, race, sex, BMI, comorbidities (hypertension, diabetes, prior CAD, prior CABG/PCI, CHF, renal dysfunction, smoking, COPD, anemia), symptom status, urgency, ipsilateral stenosis, and contralateral occlusion into a regression model to compute propensity scores for treatment assignment. We then used the propensity scores for inverse probability-weighting and weighted logistic regression to compare in-hospital stroke, in-hospital death, stroke/death, postoperative myocardial infarction (MI), stroke/death/MI, 30-day mortality and cranial nerve injury (CNI) following TCAR, tfCAS, and CEA. We also analyzed trends in the proportions of patients undergoing the three revascularization procedures over time using Cochrane-Armitage trend testing.

RESULTS

We identified 2,137 patients undergoing revascularization following prior ipsilateral carotid stenting: 668 TCAR patients (31%), 1128 tfCAS patients (53%) and 341 CEA patients (16%). In asymptomatic patients, TCAR was associated with a lower yet not statistically significant in-hospital stroke/death than tfCAS (TCAR vs tfCAS: 0.7% vs 2.0%,aOR:0.33[0.11-1.05]; p=0.06), and similar odds of stroke/death with CEA (TCAR vs CEA: 0.7% vs 0.9%,aOR:0.80[0.16-3.98]; p=0.8). Compared with CEA, TCAR was associated with lower odds of post-operative MI (0.1% vs 14%,aOR:0.02[0.00-0.10]; p<0.001), stroke/death/MI (0.8% vs 15%,aOR:0.05[0.01-0.25]; p<0.001), and CNI (0.1% vs 3.8%,aOR:0.04[0.00-0.30]; p=0.002) in this patient population. In symptomatic patients, TCAR had an unacceptably elevated in-hospital stroke/death rate of 5.1% with lower rates of CNI than CEA. We also found an increasing trend in the proportion of patients undergoing TCAR following prior ipsilateral carotid stenting (2016 to 2023: 14% to 41%), with a relative decrease in proportions of tfCAS (61% to 45%) and CEA (25% to 14%) (p<.001).

CONCLUSIONS

In asymptomatic patients with prior ipsilateral carotid artery stenting, TCAR was associated with lower odds of in-hospital stroke/death compared with tfCAS, with comparable stroke/death but lower postoperative MI and CNI rates compared with CEA. In symptomatic patients, TCAR was associated with unacceptably elevated in-hospital stroke/death rates. In line with the post-procedure outcomes, there has been a steady increase in the proportion of patients with prior ipsilateral stenting undergoing TCAR over time.

Surveillance and risk factors for early restenosis following transcarotid artery revascularization

OBJECTIVE

Restenosis after transcarotid artery revascularization (TCAR) is a known complication. When identified in the early postoperative period, it may be related to technique. We evaluated our TCAR experience to identify potentially modifiable factors impacting restenosis.

METHODS

This is a single-institution, retrospective review of patients undergoing TCAR from November 2017 to July 2022. Restenosis was defined as >50% stenosis on duplex ultrasound (DUS) examination or computed tomographic angiography (CTA). Continuous variables were compared using Kruskal-Wallis's test. Categorical variables were compared using the Fisher's exact test.

RESULTS

Of 61 interventions, 11 (18%) developed restenosis within the median follow-up of 345 days (interquartile range, 103-623 days). Among these patients, 82% (9/11) had >50% stenosis, and 18% (2/11) had >80% stenosis. Both patients with high-grade restenosis were symptomatic and underwent revascularization. Diagnosis of post-TCAR restenosis was via DUS examination in 45% (5/11), CTA in 18% (2/11), or both CTA/DUS examination in 36% (4/11). Restenosis occurred within 1 month in 54% (6/11) and 6 months in 72% (8/11) of patients. However, three of the six patients with restenosis within 1 month had discordant findings on CTA vs DUS imaging. Patient comorbidities, degree of preoperative stenosis, medical management, balloon size, stent size, lesion characteristics, and predilatation angioplasty did not differ. Patients with restenosis were younger (P = .02), had prior ipsilateral endarterectomy (odds ratio [OR], 6.5; P = .02), had history of neck radiation (OR, 18.3; P = .01), and lower rate of postdilatation angioplasty (OR, 0.11; P = .04), without an increased risk of neurological events.

CONCLUSIONS

Although post-TCAR restenosis occurred in 18% of patients, only 3% of patients had critical restenosis and required reintervention. Patient factors associated with restenosis were younger age, prior endarterectomy, and history of neck radiation. Although early restenosis may be mitigated by improved technique, the only technical factor associated with restenosis was less use of postdilatation angioplasty. Balancing neurological risk, this factor may have increased application in appropriate patients. Diagnosis of restenosis was inconsistent between imaging modalities; current surveillance paradigms and diagnostic thresholds may warrant reconsideration.

Cutting Balloon Angioplasty for Severe In-Stent Restenosis after Carotid Artery Stenting: Long-Term Outcomes and Review of Literature

PURPOSE

Cutting balloon-percutaneous transluminal angioplasty (CB-PTA) is a feasible treatment option for in-stent restenosis (ISR) after carotid artery stenting (CAS). However, the longterm durability and safety of CB-PTA for ISR after CAS have not been well established.

MATERIALS AND METHODS

We retrospectively reviewed medical records of patients with ISR after CAS who had been treated with CB-PTA from 2012 to 2021 in our center. Detailed information of baseline characteristics, periprocedural and long-term outcomes, and follow-up imaging was collected.

RESULTS

During 2012-2021, a total of 301 patients underwent CAS. Of which, CB-PTA was performed on 20 lesions exhibiting severe ISR in 18 patients following CAS. No patient had any history of receiving carotid endarterectomy or radiation therapy. These lesions were located at the cervical segment of the internal carotid artery (n=16), proximal external carotid artery (n=1), and distal common carotid artery (n=1). The median time interval between initial CAS and detection of ISR was 390 days (interquartile range 324-666 days). The follow-up period ranged from 9 months to 9 years with a median value of 21 months. Four patients (22.2%) were symptomatic. The average of stenotic degree before and after the procedure was 79.2% and 34.7%, respectively. Out of the 18 patients receiving CB-PTA, 16 (88.9%) did not require additional stenting, and 16 (88.9%) did not experience recurrent ISR during the follow-up period. Two patients who experienced recurrent ISR were successfully treated with CB-PTA and additional stenting. No periprocedural complication was observed in any case.

CONCLUSION

Regarding favorable periprocedural and long-term outcomes in our single-center experience, CB-PTA was a feasible and safe option for the treatment of severe ISR after CAS.

Comparison of carotid endarterectomy and repeated carotid angioplasty and stenting for in-stent restenosis (CERCAS trial): a randomised study

BACKGROUND AND AIM

In-stent restenosis (ISR) belongs to an infrequent but potentially serious complication after carotid angioplasty and stenting in patients with severe carotid stenosis. Some of these patients might be contraindicated to repeat percutaneous transluminal angioplasty with or without stenting (rePTA/S). The purpose of the study is to compare the safety and effectiveness of carotid endarterectomy with stent removal (CEASR) and rePTA/S in patients with carotid ISR.

METHODS

Consecutive patients with carotid ISR (≥80%) were randomly allocated to the CEASR or rePTA/S group. The incidence of restenosis after intervention, stroke, transient ischaemic attack myocardial infarction and death 30 days and 1 year after intervention and restenosis 1 year after intervention between patients in CEASR and rePTA/S groups were statistically evaluated.

RESULTS

A total of 31 patients were included in the study; 14 patients (9 males; mean age 66.3±6.6 years) were allocated to CEASR and 17 patients (10 males; mean age 68.8±5.6 years) to the rePTA/S group. The implanted stent in carotid restenosis was successfully removed in all patients in the CEASR group. No clinical vascular event was recorded periproceduraly, 30 days and 1 year after intervention in both groups. Only one patient in the CEASR group had asymptomatic occlusion of the intervened carotid artery within 30 days and one patient died in the rePTA/S group within 1 year after intervention. Restenosis after intervention was significantly greater in the rePTA/S group (mean 20.9%) than in the CEASR group (mean 0%, p=0.04), but all stenoses were <50%. Incidence of 1-year restenosis that was ≥70% did not differ between the rePTA/S and CEASR groups (4 vs 1 patient; p=0.233).

CONCLUSION

CEASR seems to be effective and save procedures for patients with carotid ISR and might be considered as a treatment option.

TRIAL REGISTRATION NUMBER

NCT05390983.

Treatment of the Carotid In-stent Restenosis: A Systematic Review

Background and Purpose: In-stent restenosis (ISR) after carotid artery stent (CAS) is not uncommon. We aimed to evaluate therapeutic options for ISR after CAS. Methods: We searched PubMed and EMBASE until November 2, 2020 for studies including the treatment for ISR after CAS. Results: In total, 35 studies, covering 1,374 procedures in 1,359 patients, were included in this review. Most cases (66.3%) were treated with repeat CAS (rCAS), followed by percutaneous transluminal angioplasty (PTA) (17.5%), carotid endarterectomy (CEA) (14.3%), carotid artery bypass (1.5%), and external beam radiotherapy (0.4%). The rates of stroke & TIA within the postoperative period were similar in three groups (PTA 1.1%, rCAS 1.1%, CEA 1.5%). CEA (2.5%) was associated with a slightly higher rate of postoperative death than rCAS (0.7%, P = 0.046). Furthermore, the rate of long-term stroke & TIA in PTA was 5.7%, significantly higher than rCAS (1.8%, P = 0.036). PTA (27.8%) was also associated with a significantly higher recurrent restenosis rate than rCAS (8.2%, P = 0.002) and CEA (1.6%, P < 0.001). The long-term stroke & TIA and recurrent restenosis rates showed no significant difference between rCAS and CEA. Conclusions: rCAS is the most common treatment for ISR, with low postoperative risk and low long-term risk. CEA is an important alternative for rCAS. PTA may be less recommended due to the relatively high long-term risks of stroke & TIA and recurrent restenosis.

The management of carotid restenosis: a comprehensive review

Carotid artery stenosis (CS) is a major medical problem affecting approximately 10% of the general population 80 years or older and causes stroke in approximately 10% of all ischemic events. In patients with symptomatic, moderate-to-severe CS, carotid endarterectomy (CEA) and carotid angioplasty and stenting (CAS), has been used to lower the risk of stroke. In primary CS, CEA was found to be superior to best medical therapy (BMT) according to 3 large randomized controlled trials (RCT). Following CEA and CAS, restenosis remains an unsolved problem involving a large number of patients as the current treatment recommendations are not as clear as those for primary stenosis. Several studies have evaluated the risk of restenosis, reporting an incidence ranging from 5% to 22% after CEA and an in-stent restenosis (ISR) rate ranging from 2.7% to 33%. Treatment and optimal management of this disease process, however, is a matter of ongoing debate, and, given the dearth of level 1evidence for the management of these conditions, the relevant guidelines lack clarity. Moreover, the incidence rates of stroke and complications in patients with carotid stenosis are derived from studies that did not use contemporary techniques and materials. Rapidly changing guidelines, updated techniques, and materials, and modern medical treatments make actual incidence rates barely comparable to previous ones. For these reasons, RCTs are critical for determining whether these patients should be treated with more aggressive treatments additional to BMT and identifying those patients indicated for surgical or endovascular treatments. This review summarizes the current evidence and controversies concerning the risks, causes, current treatment options, and prognoses in patients with restenosis after CEA or CAS.

Meta-analysis of redo stenting versus endarterectomy for in-stent stenosis after carotid artery stenting

OBJECTIVE

The development of in-stent restenosis (ISR) hinders the long-term patency of carotid artery stenting (CAS), yet no optimal treatment has been established. In the present study, we compared the outcomes of redo CAS (rCAS) and carotid endarterectomy (CEA) for ISR.

METHODS

A systematic search using the terms "in-stent restenosis," "carotid endarterectomy," and "carotid artery stenting" was conducted in the PubMed, Embase, and Cochrane databases. Studies reporting perioperative stroke, death, and other important complications of rCAS or CEA for ISR after previous CAS with four or more patients were included. Pooled and sensitivity analyses were conducted to synthesize and compare estimates of the outcomes.

RESULTS

A total of 11 studies with 1057 patients who had undergone rCAS (n = 894) or CEA (n = 163) met the inclusion criteria. The CEA group had a significantly greater proportion of symptomatic patients (rCAS vs CEA, 30.4% vs 42.1%; P < .01). The duration from primary CAS to reintervention was relatively longer in the CEA group (rCAS vs CEA, median, 8.8 months [range, 3-26 months] vs 19.9 months [range, 0-54 months]). In the rCAS group, a greater proportion of patients had hypertension, hypercholesterolemia, and coronary artery disease and had received antiplatelet therapy before reintervention. Because of insufficient data or a low incidence, the only complications feasible for further analysis were restenosis, myocardial infarction, cranial nerve injury, and neck hematoma. No significant differences were found in the primary end point of mortality/stroke event-free rate (rCAS vs CEA, 99% vs 98%; P > .05) or other secondary end points (event-free restenosis, 100% vs 100%; event-free myocardial infarction, 100% vs 98%; event-free cranial nerve injury, 100% vs 98%; event-free neck hematoma, 100% vs 100% for rCAS vs CEA; P > .05 for all).

CONCLUSIONS

rCAS is commonly used to treat patients with severe and/or symptomatic ISR after primary CAS. Although the endovascular approach is less invasive, both rCAS and CEA can be performed safely with similar short- and midterm outcomes of stroke, death, and surgery-related complications.

A Review on the Comparison of Different Treatments for Carotid In-Stent Restenosis

Different treatment options for carotid in-stent restenosis (ISR) have been reported with good outcome, including carotid endarterectomy (CEA), repeated carotid angioplasty stenting (CAS) and percutaneous transluminal angioplasty (PTA) with drug-coated balloons (DCBs). However, the optimal treatment option for ISR has not yet been determined. A systematic literature search was performed in the databases of Medline, Embase, Cochrane library, and unpublished data from clinicaltrials.gov from 1990 to March 1, 2019. Studies were enrolled if they reported treatment strategies for carotid ISR treatment and met the inclusion criteria. After study inclusions, data were extracted and summarized. Totally 25 cross-sectional studies were included, containing 5 comparative studies, 16 studies using repeated PTA, and 4 studies adopting CEA treatment. Our study summarized the current available data, showing that all the studies could effectively relieve the carotid ISR by significantly improving the angiographic stenosis and decreasing the peak systolic velocity values. Meanwhile, CEA treatment had the best long-term effects in relieving restenosis, while re-PTA with stenting/balloon angioplasty had a certain rate of restenosis, ranging from 33% to 83%. Furthermore, re-PTA/stenting and balloon angioplasty treatment had less complications compared with CEA. Also, we analyzed the risk factors that might affect the long-term prognosis of carotid ISR patients. The therapeutic measures for carotid ISR had their own features, with CEA had the highest efficacy while re-PTA/stenting and balloon angioplasty were with less complications. More large-scale comparative clinical studies are needed to further ascertain the best strategies.

Management of De Novo Carotid Stenosis and Postintervention Restenosis-Carotid Endarterectomy Versus Carotid Artery Stenting-a Review of Literature

The current literature indicates carotid endarterectomy (CEA) as the preferred treatment for symptomatic, moderate to severe carotid artery stenosis. However, recommendations for the management of acute tandem stenosis and complete occlusion, as well as postintervention restenosis of the carotid artery, remain controversial. Here, we review the literature evaluating these conditions and provide suggestions for clinical decision-making. Acute tandem stenosis or occlusion of the common and internal carotid arteries may be treated with angioplasty alone, reserving carotid artery stenting (CAS) or CEA for severe and complex cases. Patients who underwent CEA and developed ipsilateral restenosis may be subjected to angioplasty followed by CAS, which carries a lower risk of cranial nerve injury and subsequent restenosis of the artery. For post-CAS restenosis, current evidence recommends angioplasty and CAS for the management of moderate stenosis and CEA for severe stenosis of the carotid artery. Given the lack of level 1 evidence for the management of these conditions, the abovementioned recommendations may assist clinical decision-making; however, each case and its unique risks and benefits need to be assessed individually. Future studies evaluating and defining the risks and benefits of specific treatment strategies, such as CEA and CAS, in patients with acute tandem stenosis, occlusion, and postintervention restenosis of the carotid artery need to be conducted.

Carotid endarterectomy for in-stent restenosis: a case report and literature review

It is relatively difficult to treat restenosis when restenosis occurs following carotid artery stenting. Endarterectomy with simultaneous stent removal is an effective approach when restenosis occurs. The treatment method is still not well known. The present paper reports a case of restenosis after stenting that was treated with endarterectomy with a satisfactory treatment outcome. The patient, a 74-year-old male, underwent stenting 10 months before he was re-hospitalized. He seemed to recover well after stenting until one month before he was re-hospitalized, when he presented symptoms of cerebral ischemia. Imaging examination revealed that in-stent stenosis had reoccurred, with the stenosis degree ranging from 70-99%. He was given endarterectomy treatment, and intra-operative findings showed that the stent grew into a carotid artery plaque and protruded below the adventitia and that the stent lumen was not covered by carotid artery intima. The surgery completely and successfully removed the plaque and the stent, while the adventitia was completely preserved. Follow-up indicated that there was no stenosis in the carotid artery, and the prognosis was good. Relevant literature was also reviewed in this paper, and the authors suggested that carotid artery plaque and stent endarterectomy is beneficial. However, surgical treatment for in-stent stenosis remains a challenging option.

Prosthetic bypass for restenosis after endarterectomy or stenting of the carotid artery

OBJECTIVE

The objective of this study was to evaluate the results of prosthetic carotid bypass (PCB) with polytetrafluoroethylene (PTFE) grafts as an alternative to carotid endarterectomy (CEA) in treatment of restenosis after CEA or carotid artery stenting (CAS).

METHODS

From January 2000 to December 2014, 66 patients (57 men and 9 women; mean age, 71 years) presenting with recurrent carotid artery stenosis ≥70% (North American Symptomatic Carotid Endarterectomy Trial [NASCET] criteria) were enrolled in a prospective study in three centers. The study was approved by an Institutional Review Board. Informed consent was obtained from all patients. During the same period, a total of 4321 CEAs were completed in the three centers. In these 66 patients, the primary treatment of the initial carotid artery stenosis was CEA in 57 patients (86%) and CAS in nine patients (14%). The median delay between primary and redo revascularization was 32 months. Carotid restenosis was symptomatic in 38 patients (58%) with transient ischemic attack (n = 20) or stroke (n = 18). In this series, all patients received statins; 28 patients (42%) received dual antiplatelet therapy, and 38 patients (58%) received single antiplatelet therapy. All PCBs were performed under general anesthesia. No shunt was used in this series. Nasal intubation to improve distal control of the internal carotid artery was performed in 33 patients (50%), including those with intrastent restenosis. A PTFE graft of 6 or 7 mm in diameter was used in 6 and 60 patients, respectively. Distal anastomosis was end to end in 22 patients and end to side with a clip distal to the atherosclerotic lesions in 44 patients. Completion angiography was performed in all cases. The patients were discharged under statin and antiplatelet treatment. After discharge, all of the patients underwent clinical and Doppler ultrasound follow-up every 6 months. Median length of follow-up was 5 years.

RESULTS

No patient died, sustained a stroke, or presented with a cervical hematoma during the postoperative period. One transient facial nerve palsy and two transient recurrent nerve palsies occurred. Two late strokes in relation to two PCB occlusions occurred at 2 years and 4 years; no other graft stenosis or infection was observed. At 5 years, overall actuarial survival was 81% ± 7%, and the actuarial stroke-free rate was 93% ± 2%. There were no fatal strokes.

CONCLUSIONS

PCB with PTFE grafts is a safe and durable alternative to CEA in patients with carotid restenosis after CEA or CAS in situations in which CEA is deemed either hazardous or inadvisable.

Carotid Artery Stenting with Distal Protection Using the Carotid Wallstent and Filterwire Neuroprotection: Single-Center Experience of 380 Cases with Midterm Outcomes

Emerging data have supported the clinical efficacy of carotid artery stenting (CAS) in stroke prevention in high-risk surgical patients. This study was performed to evaluate the midterm clinical outcome of CAS using the Carotid Wallstent and FilterWire distal protection (both Boston Scientific, Natick, MA) at an academic institution. Risk factors for in-stent restenosis (ISR) were also analyzed. Clinical variables and treatment outcome of high-risk patients who underwent Carotid Wallstent placement with FilterWire EX/EZ neuroprotection were analyzed during a recent 54-month period. Three hundred eighty CAS procedures were performed in 354 patients. Technical success was achieved in 372 cases (98%), and symptomatic lesions existed in 85 (24%) patients. No patient experienced periprocedural mortality or neuroprotective device–related complication. The 30-day stroke and death rate was 2.7%, and the overall complication rate was 6.9%. The overall major or fatal stroke rates in symptomatic and asymptomatic patients were 4.6% and 1.3%, respectively (not significant). The overall stroke and death rates between the symptomatic and asymptomatic groups were 5.8% and 2.4%, respectively (not significant). The median follow-up period was 29 months (range 1–53 months). With Kaplan-Meier analysis, the rates of freedom from 60% or greater ISR after CAS procedures at 12, 24, 36, and 48 months were 97%, 94%, 92%, and 90%, respectively. The rates of freedom from all fatal and nonfatal strokes at 12, 24, 36, and 48 months were 97%, 91%, 89%, and 85%, respectively. Multivariable analysis of significant univariate predictors identified that postendarterectomy stenosis (odds ratio [OR] 3.98, p = .02) and multiple stent placement (OR 3.68, p = .03) were independent predictors of ISR. Our study yielded favorable short-term and midterm clinical results using Carotid Wallstent with FilterWire neuroprotection. Late follow-up results showed low rates of fatal and nonfatal stroke and favorable ISR rates compared with other carotid stent trials. Postendarterectomy and multiple stent placement were associated with subsequent ISR.

Outcomes of 1000 Carotid Wallstent Implantations

Purpose: To evaluate the outcomes of carotid artery stenting (CAS) with Wallstents in a single-center experience. Methods: From January 2003 to December 2013, 1000 carotid artery lesions were treated with Carotid Wallstents under cerebral protection in 877 patients (mean age 71.7±8 years; 621 men). Indications for treatment were de novo lesions (>70% asymptomatic and >60% symptomatic); stenoses following carotid endarterectomy, radiation, or neck surgery; contralateral laryngeal nerve palsy; and high surgical risk. All the patients underwent duplex ultrasound and clinical evaluation during follow-up; radiography was performed when fracture or stent migration was suggested by ultrasound. Results: Procedure success was achieved in 99.3% of patients. Major and minor 30-day adverse events occurred in 2.1% of patients, including stroke (1.8%: 1.3% minor, 0.5% major), myocardial infarction (0.1%), and death (0.2%). Plaque morphology, nature of stenosis, and symptomatic status were significantly associated with the risk of postoperative neurologic events. Restenosis occurred in 3.2% at a mean 45.5-month follow-up and was significantly associated with diabetes, smoking, symptomatic stenosis, de novo stenosis, and calcification (plaque III/IV). No fracture or migration was registered during follow-up. Conclusion: CAS is a valid method for treating carotid artery disease, with very low rates of major adverse events and neurologic complications. The Carotid Wallstent seems to have excellent results, even with complex plaque morphology, and a low incidence of restenosis at follow-up.

Meta-Analysis of Studies Evaluating the Effect of Cilostazol on Major Outcomes After Carotid Stenting

PURPOSE

To evaluate the effect of cilostazol on major outcomes after carotid artery stenting (CAS).

METHODS

A systematic literature review was conducted conforming to established criteria in order to identify articles published prior to May 2015 evaluating major post-CAS outcomes in patients treated with cilostazol vs patients not treated with cilostazol. Major outcomes included in-stent restenosis (ISR) within the observation period, the revascularization rate, major/minor bleeding, and the myocardial infarction/stroke/death rate (MI/stroke/death) at 30 days and within the observation period. Data were pooled for all studies containing adequate data for each outcome investigated; effect estimates are presented as the odds ratios (ORs) and 95 confidence intervals (CI).

RESULTS

Overall, 7 studies pertaining to 1297 patients were eligible. Heterogeneity was low among studies so a fixed-effect analysis was conducted. Six studies (n=1233) were compared for the ISR endpoint, showing a significantly lower ISR rate with cilostazol treatment after a mean follow-up of 20 months (OR 0.158, 95% CI 0.072 to 0.349, p<0.001). Five studies (n=649) were compared regarding 30-day MI/stroke/death (OR 0.724, 95% CI 0.293 to 1.789, p=0.484) and 3 studies (n=1076) were analyzed regarding MI/stroke/death within the entire follow-up period (OR 0.768, 95% CI 0.477 to 1.236, p=0.276); no significant difference was found between the groups. Data on bleeding rates and revascularization rates post ISR were inadequate to conduct further analysis.

CONCLUSION

Cilostazol seems to decrease total ISR rates in patients undergoing CAS without affecting MI/stroke/death events, both in the early and late settings.

The myth of restenosis after carotid angioplasty and stenting

BACKGROUND AND PURPOSE

Reported rates of in-stent restenosis after carotid artery stenting (CAS) vary, and restenosis risk factors are poorly understood. We evaluated restenosis rates and risk factors, and compared patients with 'hostile-neck' carotids (a history of ipsilateral neck surgery or irradiation) and atherosclerotic lesions.

METHODS

Demographic, clinical, and radiological characteristics of patients undergoing cervical CAS between 1995 and 2010 with at least 1 month of follow-up were reviewed. Patients with substantial (≥50%) radiographic restenosis were compared with those without significant restenosis to identify restenosis risk factors.

RESULTS

The analysis included 121 patients with 133 stented vessels; 91 (68.4%) lesions were symptomatic. Indications for stent placement included hostile-neck lesions, substantial surgical comorbidities, inclusion in a randomized carotid stenting trial, acute carotid occlusion, tandem stenosis, large pseudoaneurysm, high carotid bifurcation, and contralateral laryngeal nerve palsy. Procedures were technically successful in all but one lesion (99.2%). Perioperative stroke occurred in four cases (3.0%). Mean follow-up was 38 months (range 1-204 months), during which 23 vessels (17.3%) developed restenosis. Hostile-neck carotids (n=57) comprised 42.9% of all vessels treated and were responsible for 15 of 23 restenosis cases, resulting in a significantly higher restenosis rate than that of primary atherosclerotic lesions (26.3% vs 10.5%, p=0.017). By univariate analysis, the presence of calcified plaque was significantly associated with the incidence of in-stent restenosis (p=0.02).

CONCLUSIONS

Restenosis rates after carotid angioplasty and stenting are low. Patients with a history of ipsilateral neck surgery or irradiation are at higher risk for substantial radiographic and symptomatic restenosis.

Comparative Review of the Treatment Methodologies of Carotid Stenosis

The treatment of carotid stenosis entails three methodologies, namely, medical management, carotid angioplasty and stenting (CAS), as well as carotid endarterectomy (CEA). The North American Symptomatic Carotid Endarterectomy Trial (NASCET) and European Carotid Surgery Trial (ECST) have shown that symptomatic carotid stenosis greater than 70% is best treated with CEA. In asymptomatic patients with carotid stenosis greater than 60%, CEA was more beneficial than treatment with aspirin alone according to the Asymptomatic Carotid Atherosclerosis (ACAS) and Asymptomatic Carotid Stenosis Trial (ACST) trials. When CAS is compared with CEA, the CREST resulted in similar rates of ipsilateral stroke and death rates regardless of symptoms. However, CAS not only increased adverse effects in women, it also amplified stroke rates and death in elderly patients compared with CEA. CAS can maximize its utility in treating focal restenosis after CEA and patients with overwhelming cardiac risk or prior neck irradiation. When performing CEA, using a patch was equated to a more durable result than primary closure, whereas eversion technique is a new methodology deserving a spotlight. Comparing the three major treatment strategies of carotid stenosis has intrinsic drawbacks, as most trials are outdated and they vary in their premises, definitions, and study designs. With the newly codified best medical management including antiplatelet therapies with aspirin and clopidogrel, statin, antihypertensive agents, strict diabetes control, smoking cessation, and life style change, the current trials may demonstrate that asymptomatic carotid stenosis is best treated with best medical therapy. The ongoing trials will illuminate and reshape the treatment paradigm for symptomatic and asymptomatic carotid stenosis.

Carotid artery stenting has increased risk of external carotid artery occlusion compared with carotid endarterectomy

OBJECTIVE

The external carotid artery (ECA) can be an important source of cerebral blood flow in cases of high-grade internal carotid artery stenosis or occlusion. However, the treatment of the ECA is fundamentally different between carotid endarterectomy (CEA) and carotid artery stenting (CAS). CEA is routinely associated with endarterectomy of the ECA, whereas CAS excludes the ECA from direct flow. We hypothesize that these differences make ECA occlusion more common after CAS. Further, the impact of CAS on blood flow into the ECA is interesting because the flow from the stent into the ECA is altered in a way that may promote local inflammation and may influence in-stent restenosis (ISR). Thus, our objective was to use our institutional database to identify whether CAS increased the rate of ECA occlusion and, if it did, whether ECA occlusion was associated with ISR.

METHODS

Patients undergoing CAS or CEA from February 2007 to February 2012 were identified from our institutional carotid therapy database. Preoperative and postoperative images of patients who followed up in our institution were included in the analysis of ECA occlusion and rates of ISR.

RESULTS

There were 210 (67%) CAS patients and 207 (60%) CEA patients included in this analysis. Despite CAS patients being younger (68 vs 70 years), having shorter follow-up (12.5 vs 56.2 months), and being more likely to take clopidogrel (97% vs 35%), they had an increased rate of ECA occlusion (3.8%) compared with CEA patients (0.4%). CAS patients who went on to ECA occlusion had an increased incidence of prior neck irradiation (50% vs 15%; P = .03), but we did not identify an association of ECA occlusion with ISR >50%.

CONCLUSIONS

Whereas prior publications have identified increased rates of external carotid stenosis, this is the first demonstration of increased ECA occlusion after CAS. However, ECA occlusion is uncommon (∼4%) and did not have an association with ISR >50%. Future work modeling ECA flow patterns before and after CAS will be used to further test this interaction.

Stent placement for treatment of long-segment (≥40 mm) carotid atherosclerotic stenosis: results and long-term follow-up in a single-center experience

BACKGROUND

Treatment of long segment carotid stenosis (≥40 mm) with carotid artery stenting (CAS) has rarely been reported. In randomized trials, use of longer stents (>40 mm) has been associated with adverse clinical events. Here, we report our preliminary experience on the stent length and outcome in treating long segment carotid arterial stenosis.

METHODS AND RESULTS

Between August 2003 and February 2013, 22 patients with long segment stenosis of the carotid artery were treated by CAS. The mean stent length was 58.5 mm (50-60 mm). The procedures were successful in all patients, and all reported remarkable relief of symptoms immediately after stent placement. Complications included 1 case of cerebral hemorrhage and one death from myocardial infarction at 10 months. The mean follow up was 27.3 months (10-60 months). One follow-up was lost. 2 patients had late stent thrombosis at 22 and 36 months by CTA follow-up. 18 patients had persistent relief, and angiography/CTA showed normal carotid flow.

CONCLUSIONS

Our study showed that stenting for long carotid stenosis (≥40 mm) can be beneficial. Large scale clinical trial is needed to further evaluate its efficacy and safety.

Influence of the hostile neck on restenosis after carotid stenting

BACKGROUND

Carotid artery stenting (CAS) for carotid stenosis is favored over carotid endarterectomy (CEA) in patients with a hostile neck from prior CEA or cervical irradiation (XRT). However, the restenosis rate after CAS in patients with hostile necks is variable in the literature. The objective of this study was to quantify differences in the in-stent restenosis (ISR)/occlusion and reintervention rates after CAS in patients with and without a hostile neck. Here we hypothesize that patients with hostile necks have an increased ISR, and that this increase may add morbidity to these patients.

MATERIALS AND METHODS

All patients undergoing CAS from 2007 to 2013 for carotid artery stenosis with follow-up imaging at our institution were queried from our carotid database (n = 236). Patients with hostile necks, including both CAS after prior CEA (n = 65) and prior XRT (n = 37), were compared with patients who underwent CAS for other reasons including both anatomical (n = 46) and medical comorbidities (n = 88). The primary end points were ISR, repeat intervention, and stent occlusion. Secondary end points of the study were stroke/myocardial infarction (MI)/death at 30 days, perioperative cardiovascular accident, transient ischemic attack, MI, groin access complications, hyperperfusion syndrome, and periprocedural hypotension or bradycardia.

RESULTS

Despite the hostile neck cohort being younger and having lower incidence of chronic obstructive pulmonary disease, coronary artery disease, and renal insufficiency, they had a greater incidence of ISR (11% vs. 4%; P = .03) and required more reinterventions (8% vs. 2%; P = .04). Stent occlusion and periprocedural morbidity/mortality were not different between groups.

CONCLUSIONS

Patients with hostile necks have increased risk of restenosis and need for reinterventions after CAS compared with patients without a hostile neck. However, they do not appear to have higher rates of stent occlusion or per-procedural events.

Carotid restenosis after endarterectomy and stenting: a critical issue?

BACKGROUND

Carotid artery stenting (CAS) is currently considered a valid alternative to carotid endarterectomy (CEA) for the prevention of stroke in high-risk patients. One of the most important issues for both of these techniques is carotid restenosis. The aim of our study was to evaluate the incidence of post-CEA and post-CAS restenosis in a large cohort of patients in a single high-volume center.

METHODS

Between December 2000 and December 2010, 2453 CEA and 2628 CAS procedures were performed in the Vascular and Endovascular Surgery Unit at our institution. The mean age of patients was 73.8 years (range 55‒89 years), 78% of whom were men. Indications for carotid revascularization were: presence of symptomatic carotid artery stenosis of >70%, or asymptomatic stenosis of at least 80%, especially in patients with vulnerable plaques.

RESULTS

Mild and long-term results after CEA and CAS were similar. The overall perioperative neurologic complication rate (minor and major stroke) was similar in the 2 groups. At 1-year follow-up the restenosis rate after CEA was 1.58%. In-stent restenosis after CAS occurred in 1.67% of the procedures. All but 3 arteries had been treated for postsurgical restenosis. All lesions were approached secondarily with endovascular procedures. Statistical analysis demonstrated that post-CEA restenosis was the most important predictive factor for the development of in-stent restenosis after CAS.

CONCLUSIONS

This review of our 10-year experience confirms that patients who develop restenosis after CEA are also prone to developing in-stent restenosis after CAS.

[Carotid artery stenting technique]

Over the past 25 years carotid artery stenting (CAS) has emerged as an alternative to carotid endarterectomy (CEA). Most of all younger patients and symptomatic patients with contralateral carotid artery occlusion particularly benefit from CAS. To achieve an optimal result with CAS, patient selection and even more important, knowledge and experience of the interventionist is crucial. The periprocedural complication rate of CAS in large experienced centers is lower (2-3%) than those in randomized trials. Several different devices are now available which allow the procedure to be tailored according to patient anatomy and lesion complexity. Complications like hyperperfusion syndrome and intracerebral bleeding, rupture of side branches of the external or internal carotid artery as well as problems caused by slow flow can be widely avoided by adequate experience.

Indications for treatment of recurrent carotid stenosis

Background

There is significant variation in the indications for intervention in patients with recurrent carotid artery stenosis. The aim of the present study was to describe these indications in a contemporary cohort of patients.

Methods

This was a systematic review of all peer-reviewed studies reporting on the indications for carotid intervention in patients with recurrent stenosis after carotid endarterectomy (CEA) or carotid artery stenting (CAS) that were published between 1990 and 2012.

Results

There were 50 studies reporting on a total of 3524 patients undergoing a carotid procedure; of these, 3478 underwent CEA as the initial intervention. Reintervention was by CEA in 2403 patients and by CAS in 1121. Only 54·7 per cent of the patients were treated for any symptoms and, importantly, just 444 (23·1 per cent of 1926 symptomatic patients) underwent intervention for documented ipsilateral symptoms. None of the studies reported whether the patients were evaluated for other sources of emboli. The remaining 45·3 per cent of patients had asymptomatic restenosis and in the majority of the studies were treated when the degree of stenosis exceeded 80 per cent. The time to repeat intervention was significantly longer in patients with recurrent atherosclerosis, in asymptomatic patients and in patients undergoing CEA.

Conclusion

The reported criteria for retreatment of carotid stenosis were not rigorous and there is still significant ambiguity surrounding the indications for intervention.

Stent placement for treatment of long segment (≥80 mm) carotid artery stenosis in patients with Takayasu disease

PURPOSE

To evaluate the effectiveness and safety of carotid artery stent (CAS) placement for treatment of long segment stenosis in patients with Takayasu arteritis.

MATERIALS AND METHODS

Between January 2002 and February 2012, all patients with Takayasu arteritis found to have long segment (≥80 mm) carotid artery stenoses at a single institution were retrospectively analyzed. Five patients treated by CAS placement with either long or multiple self-expandable stents were included. All patients had focal neurologic symptoms, including three strokes and two transient ischemic attacks (TIAs). Six self-expanding stents were used in five patients. The mean follow-up period was 19.2 months (range, 6-30 mo); all patients had clinical evaluation, laboratory examination, and vascular imaging follow-up.

RESULTS

Improvement in clinical symptoms was shown after successful angioplasty. There were no perioperative or in-hospital deaths. Four patients exhibited persistent relief, and repeated angiography or computed tomography (CT) angiography showed normal flow. One patient stopped taking her medications after CAS placement and became symptomatic 8 months later as a result of a severe in-stent stenosis.

CONCLUSIONS

CAS placement was shown to be a feasible option for treating long segment (≥80 mm) stenosis of carotid arteries in patients with Takayasu arteritis with encouraging results.

Economic impact of endarterectomy vs carotid artery stenting: a one year, single centre study

AIMS

Carotid artery stenting (CAS) has been suggested by some clinicians as an alternative to endarterectomy (CEA), especially in some specific subgroups of the population. The aim of this study is to evaluate the costs of these two procedures.

METHODS AND RESULTS

A review of costs was performed on all patients who underwent elective treatment of carotid artery stenosis between January and December 2006 (184 CAS vs 97 CEA). Clinical data had been prospectively gathered from both the CAS and the CEA groups, while financial data was obtained retrospectively to match hospital admissions with the generated charge from the hospital business office. In this series there was one major event in CEA and one transient ischaemic attacks (TIA) in CAS. One death procedure-related event occurred in CEA. The mean total cost associated with a single CEA was slashed integral 3,897.86, whereas the cost associated with CAS was slashed integral 3,806.66. It was apparent that the increasing costs involved in purchasing material for CAS, were balanced by the lower spending for hospital stay.

CONCLUSIONS

Costs for CAS and CEA are comparable. In our experience, the choice between CAS and CEA is based on the comorbidity of the patient, the type of the lesion and the preferences of the patient, without economic criteria being important.

New possibilities in the endovascular treatment of supraaortic vessels

Cerebrovascular disease, including stroke, represents the third-leading cause of death in Hungary and a leading cause of disability among the elderly population. The majority of all strokes are ischemic, mostly secondary to thromboembolic disease of the supraaortic vessels. We investigated new therapeutic methods in the endovascular treatment of these diseases. Surgical revascularization of supraaortic trunk stenosis is associated with high morbidity and mortality rates. Balloon angioplasty has become an increasingly accepted treatment of stenoocclusive supraaortic arterial disease. Natural history data and treatment guidelines do not exist for innominate and proximal common carotid artery lesions. We have confirmed in a large series of innominate artery angioplasties that it is a safe and effective procedure with an excellent initial success rate, with a lower complication rate than the surgical option and with a similar long-term patency rate as for surgery.

In the largest published study on transfemoral angioplasty of ostial and proximal common carotid artery stenosis we have proved that endovascular treatment has high success rate with low stroke/death rate. Carotid stenting (CAS) is an evolving alternative to surgery in the treatment of patients with carotid stenosis. Stent selection is influenced by several factors, including the carotid anatomy and lesion characteristics. We examined the wall adaptability of a new closed-cell carotid stent (NexStent), which was designed for carotid bifurcation treatment. Data obtained from angiographic and computed tomographic images indicate that the stent provides adequate expansion and adaptation to the carotid bifurcation.

There are two types of restenosis after carotid artery interventions: the early restenosis develops mainly within the first 24 months after the revascularization procedure and its pathological background is myointimal hyperplasia; on the other hand late restenosis is rather due to progression of primary atherosclerosis and occurs more than 2 years after carotid endarterectomy (CEA). We compared the early restenosis rate in a consecutive series of CAS versus CEA patients at a single cardiovascular institution. The data suggest that the incidence of restenosis after stenting was less common than after surgery.

Our results may help vascular surgeons and interventional radiologists to consider risk versus benefit when deciding treatment options for supraaortic arterial stenosis.

In stent restenosis predictors after carotid artery stenting

Purpose. The long-term efficacy of carotid artery stenting is debated. Predictors of stent restenosis are not fully investigated. Our aim was to assess the incidence of long term restenosis after CAS and to identify some predictors of restenosis. Methods. We retrospectively selected 189 treated patients and we obtained the survival Kaplan-Meier curves for overall survival, for freedom from stroke or death and from restenosis. To correlate clinical, radiological, and procedural variables to stent restenosis, an univariate analysis was performed while to determine independent predictors of restenosis, a multivariate analysis was applied. Results. At 1, 3, and 5 years, the cumulative overall survival rate was 98%, 94%, and 92% with a cumulative primary patency rate of 87%, 82.5%, and 82.5%. The percentage residual stenosis after CAS and multiple stents deployment were independent predictors of restenosis, while diabetes and tumors are suggestive but not significant predictors of restenosis. Conclusions. In our CAS experience, encouraging long-term results seem to derive from both neurological event free rate and restenosis incidence. Adequate recanalization of the treated vessel is important to limit the development of stent restenosis. Multiple stents deployment, and with less evidence, diabetes, or neoplasms has to be considered to facilitate restenosis.