Significance of atherosclerotic plaque location in recanalizing non-acute long-segment occlusion of the internal carotid artery.

To investigate the significance of atherosclerotic plaque location in hybrid surgery comprising both endovascular recanalization approaches and carotid endarterectomy for symptomatic atherosclerotic non-acute long-segment occlusion of the internal carotid artery (ICA), 162 patients were enrolled, including 120 (74.1%) patients in the proximal plaque group and 42 (25.9%) in the distal plaque group. Surgical recanalization was performed in all patients, with successful recanalization in 119 (99.2%) patients in the proximal and 39 (92.9%) in the distal plaque group. The total successful recanalization rate was 97.5% (158/162) with a failure rate of 2.5% (4/162). Periprocedural complications occurred in 5 (4.2% or 5/120) patients in the proximal plaque group, including neck infection in two (1.7%), recurrent nerve injury in 1 (0.8%), and laryngeal edema in 2 (1.7%), and 2 (4.8%) in the distal plaque group, including femoral puncture infection in 2 (4.8%). No severe complications occurred in either group. Univariate analysis showed plaque location was a significant (P = 0.018) risk factor for successful recanalization, and multivariate analysis indicated that the plaque location remained a significant independent risk factor for recanalization success (P = 0.017). In follow-up 6-48 months after the recanalization surgery, reocclusion occurred in two (2.8%) patients in the proximal plaque group and 4 (13.3%) in the distal plaque group. In conclusion, although hybrid surgery achieves similar outcomes in patients with ICA occlusion caused by either proximal or distal atherosclerotic plaques, plaque location may be a significant risk factor for successful recanalization of symptomatic non-acute long-segment ICA occlusion.

Association between hospital ownership and patient selection, management, and outcomes after carotid endarterectomy or carotid artery stenting : - Secondary data analysis of the Bavarian statutory quality assurance database.

BACKGROUND: This study analyses the association between hospital ownership and patient selection, treatment, and outcome of carotid endarterectomy (CEA) or carotid artery stenting (CAS). METHODS: The analysis is based on the Bavarian subset of the nationwide German statutory quality assurance database. All patients receiving CEA or CAS for carotid artery stenosis between 2014 and 2018 were included. Hospitals were subdivided into four groups: university hospitals, public hospitals, hospitals owned by charitable organizations, and private hospitals. The primary outcome was any stroke or death until discharge from hospital. Research was funded by Germany's Federal Joint Committee Innovation Fund (01VSF19016 ISAR-IQ). RESULTS: In total, 22,446 patients were included. The majority of patients were treated in public hospitals (62%), followed by private hospitals (17%), university hospitals (16%), and hospitals under charitable ownership (6%). Two thirds of patients were male (68%), and the median age was 72 years. CAS was most often applied in university hospitals (25%) and most rarely used in private hospitals (9%). Compared to university hospitals, patients in private hospitals were more likely asymptomatic (65% vs. 49%). In asymptomatic patients, the risk of stroke or death was 1.3% in university hospitals, 1.5% in public hospitals, 1.0% in hospitals of charitable owners, and 1.2% in private hospitals. In symptomatic patients, these figures were 3.0%, 2.5%, 3.4%, and 1.2% respectively. Univariate analysis revealed no statistically significant differences between hospital groups. In the multivariable analysis, compared to university hospitals, the odds ratio of stroke or death in asymptomatic patients treated by CEA was significantly lower in charitable hospitals (OR 0.19 [95%-CI 0.07-0.56, p = 0.002]) and private hospitals (OR 0.47 [95%-CI 0.23-0.98, p = 0.043]). In symptomatic patients (elective treatment, CEA), patients treated in private or public hospitals showed a significantly lower odds ratio compared to university hospitals (0.36 [95%-CI 0.17-0.72, p = 0.004] and 0.65 [95%-CI 0.42-1.00, p = 0.048], respectively). CONCLUSIONS: Hospital ownership was related to patient selection and treatment, but not generally to outcomes. The lower risk of stroke or death in the subgroup of electively treated patients in private hospitals might be due to the right timing, the choice of treatment modality or actually to better structural and process quality.

Stenting for subclavian steal phenomenon to restore cerebral perfusion due to acute carotid occlusion following carotid endarterectomy: a case report.

BACKGROUND: Perioperative symptomatic carotid artery occlusion after carotid endarterectomy is a rare complication. In this study, we present a case of symptomatic acute carotid artery occlusion that occurred after carotid endarterectomy in a patient with coexistent subclavian artery steal phenomenon, which was successfully treated with subclavian artery stenting. CASE PRESENTATION: A 57-year-old East Asian female presented with stenosis in the left common carotid artery and left subclavian artery along with subclavian steal. The proximal segment of the left anterior cerebral artery was hypoplastic, and the posterior communicating arteries on both sides were well-developed. Left internal carotid artery stenosis progressed during the follow-up examination; therefore, left carotid endarterectomy was performed. On the following day, symptoms of cerebral perfusion deficiency appeared due to occlusion of the left carotid artery. The stenotic origin of the left common carotid artery and the suspected massive thrombus in the left carotid artery posed challenges to carotid revascularization. Therefore, left subclavian artery stenting for the subclavian steal phenomenon was determined to be the best option for restoring cerebral blood flow to the whole brain. Her symptoms improved after the procedure, and the postprocedural workup revealed improved cerebral blood flow. CONCLUSION: Subclavian artery stenting is safe and may be helpful in patients with cerebral perfusion deficiency caused by intractable acute carotid occlusion coexisting with the subclavian steal phenomenon. Revascularization of asymptomatic subclavian artery stenosis is generally not recommended. However, cerebral circulatory insufficiency as a comorbidity may be worth considering.

Long-term cognitive and neurovascular changes after carotid endarterectomy.

BACKGROUND: Carotid endarterectomy (CEA) has been associated with both cognitive decline and improvement, but the underlying neurovascular mechanisms are unclear. The aim of this study was to investigate the relationship between neurovascular indices and cognitive changes after CEA. METHODS: We studied 55 patients with severe (≥70%) symptomatic or asymptomatic carotid stenosis before and six months after CEA. A wide array of neuropsychological tests was arranged in eight cognitive domains and cognitive functions specific to hemisphere ipsilateral to operation. Differences in cognitive performance between patients and 38 matching healthy controls were studied with linear mixed models. Neurovascular functioning and microembolic signals were assessed with transcranial Doppler ultrasound of the middle cerebral artery. Associations between neurovascular indices and cognitive change were assessed with linear regression analyses. RESULTS: On group level, the CEA patients improved more than controls in working memory, whereas no cognitive deterioration was detected. Also on individual level, improvement was most frequently observed in working memory. Worse preoperative cerebrovascular reactivity was related with improvement in cognitive functions of the ipsilateral hemisphere. Low preoperative pulsatility index was associated with improvement in executive functioning and ipsilateral cognitive functions. Poorer preoperative blood flow velocity associated with improvement in complex attention. Microembolic signals were rare. CONCLUSION: The present findings suggest that CEA may have beneficial long-term effects on cognition. These effects may specifically involve patients with impaired preoperative circulatory adaptive mechanisms.

Outcomes of carotid endarterectomy: Insights from a single-center retrospective cohort study.

OBJECTIVES: To analyze the outcomes of carotid endarterectomy in individuals with carotid artery stenosis in the context of a tertiary care center. METHODS: We carried out a retrospective cohort investigation between 2015-2022. Patient data includes demographics, risk factors, preoperative medications, and operative details. The primary outcomes were 30-day postoperative stroke and mortality rates, while the secondary outcome of the study was to assess the morbidity of the procedure. RESULTS: The mean age of the 54 patients was 66.9±9.88 years, and 57.4% were men. The 30-day stroke rate was 3.7%, and the mortality rate was 1.9%. Most patients did not develop postoperative complications; however, surgical site hematoma was the most common complication encountered (12.9%). Long-term follow-up showed disease regression in 68.5% of patients, with a minority of patients developing ipsilateral restenosis. Admission to an intensive care monitoring unit was the only independent predictor of postoperative complications. CONCLUSION: This study provided insights into the outcomes of carotid endarterectomy in patients with carotid artery stenosis, emphasizing the importance of careful patient selection and postoperative monitoring. Perioperative risks, including stroke and mortality, were within acceptable limits. Further research incorporating structured and non-structured data for predictive analyses, should explore refining patient profiling and optimizing treatment approaches for different carotid artery stenosis clinical and morphological presentations.

Thirty-day outcomes of carotid endarterectomy versus carotid artery stenting in asymptomatic and symptomatic patients: a propensity score-matched analysis.

BACKGROUND: Technological and surgical approaches to carotid artery stenting (CAS) have evolved. Modern randomised controlled trials comparing CAS and carotid endarterectomy (CEA) are limited, and information about updated post-intervention outcomes are mostly from retrospective, small studies. AIMS: This study aims to compare the 30-day outcomes of stroke, transient ischaemic attack (TIA), acute myocardial infarction (AMI) and death with propensity-matched groups of CEA and CAS in asymptomatic and symptomatic patients over a recent study period of new CAS technologies and approaches. METHODS: A retrospective, observational, multicentre analysis was conducted including consecutive symptomatic and asymptomatic patients treated with either primary CEA or CAS for internal carotid artery stenosis, between 2015 and 2022. Patients were propensity score-matched based on comorbidities and assessed according to symptom status. Primary endpoints include composite ipsilateral stroke, TIA, AMI and death within 30 days. Secondary endpoints include technical success and length of hospital stay. RESULTS: From a cohort of 1,110 patients, propensity matching produced 269 distinct treatment pairs (n=538). Most patients were asymptomatic (n=456, 85%). All 6 strokes were minor (CEA=2; CAS=4) and registered among asymptomatic patients. One AMI (CEA) and 1 patient death (CAS) were reported among symptomatic patients. Composite stroke/AMI/death were not significantly different between both types of symptom status and both revascularisation techniques (p=0.44 and p=1, respectively). Technical success was 100%. The length of hospital stay was significantly shorter in asymptomatic patients treated with CAS compared to those treated with CEA (p=0.05), but no difference was registered among symptomatic patients (p=0.32). CONCLUSIONS: Propensity-matched analysis suggests that CAS has similar postprocedural outcomes for stroke, AMI and death at 30 days compared to CEA.

Short-term outcomes after selective shunt during carotid endarterectomy: A propensity score matching analysis / Resultados a corto plazo después de shunting selectivo durante la endarterectomía carotídea con anestesia regional: un análisis de propensity score-matching

Introduction and objectives: Carotid cross-clamping during carotid endarterectomy might lead to intraoperative neurologic deficits, increasing stroke/death risk. If deficits are detected, carotid shunting has been recommended to reduce the risk of stroke. However, shunting may sustain a specific chance of embolic events and subsequently incurring harm. Current evidence is still questionable regarding its clear benefit. The aim is to determine whether a policy of selective shunt impacts the complication rate following an endarterectomy. Material and methods: From January 2013 to May 2021, all patients undergoing carotid endarterectomy under regional anesthesia with intraoperative neurologic alteration were retrieved. Patients submitted to selective shunt were compared to a non-shunt group. A 1:1 propensity score matching (PSM) was performed. Differences between the groups and clinical outcomes were calculated, resorting to univariate analysis. Results: Ninety-eight patients were selected, from which 23 were operated on using a shunt. After PSM, 22 non-shunt patients were compared to 22 matched shunted patients. Concerning demographics and comorbidities, both groups were comparable to pre and post-PSM, except for chronic heart failure, which was more prevalent in shunted patients (26.1%, P=0.036) in pre-PSM analysis. Regarding 30-day stroke and score Clavien–Dindo≥2, no significant association was found (P=0.730, P=0.635 and P=0.942, P=0.472, correspondingly, for pre and post-PSM). Conclusions: In this cohort, resorting to shunting did not demonstrate an advantage regarding 30-day stroke or a Clavien–Dindo≥2 rates. Nevertheless, additional more extensive studies are mandatory to achieve precise results concerning the accurate utility of carotid shunting in this subset of patients under regional anesthesia.(AU)

Introducción y objetivos: El pinzamiento carotídeo durante la endarterectomía carotídea podría provocar déficits neurológicos intraoperatorios, lo que aumenta el riesgo de accidente cerebrovascular/muerte. Si se detectan déficits, se ha recomendado la derivación carotídea para reducir el riesgo de accidente cerebrovascular. Sin embargo, la derivación puede sostener una posibilidad específica de eventos embólicos y, posteriormente, provocar daños. La evidencia actual aún es cuestionable con respecto a su claro beneficio. El objetivo es determinar si una política de derivación selectiva afecta la tasa de complicaciones después de una endarterectomía. Material y métodos: Desde enero de 2013 hasta mayo de 2021 se recuperaron todos los pacientes sometidos a endarterectomía carotídea bajo anestesia regional con alteración neurológica intraoperatoria. Los pacientes sometidos a derivación selectiva se compararon con un grupo sin derivación. Se realizó una coincidencia de puntuación de propensión (PSM) 1:1. Se calcularon las diferencias entre los grupos y los resultados clínicos recurriendo al análisis univariado. Resultados: Se seleccionaron 98 pacientes, de los cuales 23 fueron intervenidos mediante derivación. Después de la PSM se compararon 22 pacientes sin derivación con 22 pacientes emparejados con derivación. Con respecto a la demografía y las comorbilidades, ambos grupos fueron comparables a los de antes y después de la PSM, excepto por la insuficiencia cardíaca crónica, que fue más prevalente en los pacientes con derivación (26,1%, p=0,036) en el análisis previo a la PSM. En cuanto al accidente cerebrovascular a los 30 días y la puntuación de Clavien-Dindo≥2, no se encontró asociación significativa (p=0,730, p=0,635 y p=0,942, p=0,472, correspondientemente, para pre y post-PSM). Conclusiones: En esta cohorte recurrir a la derivación no demostró una ventaja con respecto a las tasas de ictus a los 30 días o Clavien-Dindo≥2...(AU)

Endarterectomía carotídea / Carotid endarterectomy

El autor de este artículo describe personalmente la técnica de la endarterectomía carotídea clásica con algunos detalles personales que puedan ser de utilidad o de reflexión para el lector.(AU)

The author of this paper personally describes the classical carotid endarterectomy technique with some personaldetails that may be useful or thought-provoking for the reader.(AU)

Clinical risk factors and features on computed tomography angiography in high-risk carotid artery plaque in patients with type 2 diabetes.

BACKGROUND: High-risk carotid artery plaque (HPR) is associated with a markedly increased risk of ischemic stroke. The aims of this study were: 1) to examine the prevalence of HRP in a cohort of asymptomatic adults with type 2 diabetes (T2D); 2) to investigate the relationship between HRP, established cardiovascular risk factors and computed tomography angiography (CTA) profile; and 3) to assess whether the presence of HRP is associated with an increased risk of major adverse cardiovascular events (MACE). METHODS: This was a retrospective cohort study of T2D asymptomatic patients who underwent carotid endarterectomy (CEA) from January 2018 to July 2021. The carotid atherosclerotic plaque (CAP) was assessed for the presence of ulceration, the presence of lipids, fibrosis, thrombotic deposits, hemorrhage, neovascularization, and inflammation. A CAP presenting at least five of these histological features was defined as a HRP (Group A); in all other cases it was defined as a mild to moderate heterogeneous plaque and no-HRP (Group B). CTA features included the presence of rim sign consisting of thin peripheral adventitial calcification (<2 mm) and internal soft plaque (≥2 mm), NASCET percent diameter stenosis, maximum plaque thickness, ulceration, calcification, and intraluminal thrombus were recorded. Binary logistic regression with Uni- and Multivariate was used to evaluate possible predictors for HRP while multivariable Cox Proportional Hazards was used to assess independent predictors for MACE. RESULTS: One hundred eighty-five asymptomatic patients (mean age 73±8 years, 131 men), undergoing carotid endarterectomy, were included. Of these, 124 (67%) had HRP, and the 61 (33%) did not. Diabetic complications (OR 2.4, 95% CI: 1.1-5.1, P=0.01), NASCET stenosis ≥75% (OR 2.4, 95% CI: 1.2-3.7, P=0.02) and carotid RIM sign (OR 4.3, 95% CI: 3.9-7.3, P<0.001) were independently associated with HRP. However, HRP was not associated with a higher risk of MACE (freedom from MACE at 5 years: HRP 83.4% vs. non HRP 87.8%, P=0.72) or a reduction of survival (5-year survival estimates: HRP 96.4% vs. non HRP: 94.6%, P=0.76). CONCLUSIONS: A high prevalence of HRP (67%) was observed in asymptomatic and elderly T2D patients. Independent predictors of HRP were diabetic complications, NASCET stenosis ≥75% and carotid RIM sign (OR 4.3, 95% CI: 3.9-7.3, P<0.001). HRP was not associated with an increased risk of MACE during a mean follow-up of 39±24 years.

Microplastics and Nanoplastics in Atheromas and Cardiovascular Events.

BACKGROUND: Microplastics and nanoplastics (MNPs) are emerging as a potential risk factor for cardiovascular disease in preclinical studies. Direct evidence that this risk extends to humans is lacking. METHODS: We conducted a prospective, multicenter, observational study involving patients who were undergoing carotid endarterectomy for asymptomatic carotid artery disease. The excised carotid plaque specimens were analyzed for the presence of MNPs with the use of pyrolysis-gas chromatography-mass spectrometry, stable isotope analysis, and electron microscopy. Inflammatory biomarkers were assessed with enzyme-linked immunosorbent assay and immunohistochemical assay. The primary end point was a composite of myocardial infarction, stroke, or death from any cause among patients who had evidence of MNPs in plaque as compared with patients with plaque that showed no evidence of MNPs. RESULTS: A total of 304 patients were enrolled in the study, and 257 completed a mean (±SD) follow-up of 33.7±6.9 months. Polyethylene was detected in carotid artery plaque of 150 patients (58.4%), with a mean level of 21.7±24.5 µg per milligram of plaque; 31 patients (12.1%) also had measurable amounts of polyvinyl chloride, with a mean level of 5.2±2.4 µg per milligram of plaque. Electron microscopy revealed visible, jagged-edged foreign particles among plaque macrophages and scattered in the external debris. Radiographic examination showed that some of these particles included chlorine. Patients in whom MNPs were detected within the atheroma were at higher risk for a primary end-point event than those in whom these substances were not detected (hazard ratio, 4.53; 95% confidence interval, 2.00 to 10.27; P<0.001). CONCLUSIONS: In this study, patients with carotid artery plaque in which MNPs were detected had a higher risk of a composite of myocardial infarction, stroke, or death from any cause at 34 months of follow-up than those in whom MNPs were not detected. (Funded by Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale and others; ClinicalTrials.gov number, NCT05900947.).

Perioperative and Long-Term Outcomes in Patients Undergoing Synchronous Carotid Endarterectomy and Coronary Artery Bypass Grafting: A Single-Center Experience.

INTRODUCTION: Patients requiring coronary artery bypass grafting (CABG) and carotid endarterectomy (CEA) can be managed with staged (CEA before CABG), reverse staged (CABG before CEA) or synchronous treatment. This single-center retrospective study evaluated the outcomes in patients undergoing planned synchronous CEA and CABG. METHODS: Between 2000 and 2020 a total of 185 patients with symptomatic triple-vessel or left main coronary artery disease associated with 70-99% asymptomatic or 50-99% symptomatic uni- or bilateral internal carotid artery (ICA) stenosis underwent synchronous CEA and CABG at our institution. Study endpoints were defined as mortality, stroke and myocardial infarction at 30 days. Additionally, the composite endpoint of these events was investigated. RESULTS: At 30 days, mortality, stroke and myocardial infarction rates were 5.9%, 8.1% (permanent [unresolved deficit at discharge] 5.4%) and 3.8%, respectively, and the composite endpoint was reached in 13.0% of patients. Patients suffering from a stroke more frequently had a contralateral 70-99% ICA stenosis (60.0% vs. 17.3%; p < 0.001), peripheral artery disease (73.3% vs. 38.9%; p = 0.013) and prolonged cardiopulmonary bypass time (mean 119 ± 62 min vs. 84 ± 29 min; p = 0.012). Multivariate logistic regression analysis revealed the duration of cardiopulmonary bypass (odds ratio [OR] 1.024; 95% confidence interval [CI] 1.002-1.046; p = 0.034), a history of type 2 diabetes mellitus (OR 5.097; 95% CI 1.161-22.367; p = 0.031) and peripheral artery disease (OR 5.814; 95% CI 1.231-27.457; p = 0.026) as independent risk factors for reaching the composite endpoint. CONCLUSION: Patients undergoing synchronous CEA and CABG face an elevated risk of perioperative cardiovascular events, particularly an increased stroke risk in patients with symptomatic and bilateral ICA stenosis. Graphical Abstract available for this article.

Mathematical modeling in assessing the risk of restenosis after carotid endarterectomy.

Carotid endarterectomy is the main way to combat atherosclerosis of the carotid arteries, which disrupts cerebral circulation. The generally accepted marker of atherogenesis risk are hemodynamic indices associated with near-wall shear stress. The purpose of the work is to conduct a comparative analysis of hemodynamic indices in various carotid bifurcation models. The influence of a virtual change in the geometric shape of the model in order to optimize hemodynamic indices is also being studied. On the basis of computed angiography data, carotid bifurcation models are constructed, in which critical zones of hemodynamic indices are built using computational fluid dynamics. A comparative analysis of the critical zones for different classes of models is carried out. Comparison of averaged indices for critical zones between 'normal' and post-operative groups gave more than 5-x worse results for the latter. The same results for the near-bifurcation parts of the zones give a 25% better result for postoperative models. Virtual 'removal' of insignificant plaques leads to a deterioration of the indices of up to 40% in the places of the plaque's former location. The described method makes it possible to build the indices critical zones and compare them for various types of models. A technique for virtual changing the shape of a vessel (virtual surgery) is proposed. The novelty of the approach lies in the use for comparative analysis both real vessel models and hypothetical 'improved' virtual ones, as well in the proposed division of post-operative model's critical zones into subzones of different genesis.

[Advisability of carotid endarterectomy in asymptomatic patients]. / Tselesoobraznost' karotidnoi endarterektomii u asimptomnykh bol'nykh. Analiticheskii obzor.

OBJECTIVE: To determine the optimal treatment strategy for patients with asymptomatic carotid stenosis. MATERIAL AND METHODS: The authors reviewed clinical guidelines for the management of patients with asymptomatic carotid stenosis 60-99%, as well as medical studies and meta-analyses comparing carotid endarterectomy and optimal drug therapy in asymptomatic patients between 1993 and 2023. RESULTS: The choice of treatment strategy for patients with asymptomatic carotid artery stenosis is still a controversial issue. There were several large randomized clinical trials comparing carotid endarterectomy with optimal medical therapy in asymptomatic patients at the end of the 20th century. However, drug therapy has undergone significant changes calling into question the relevance of previous results. This review highlights the evolution of management of patients with asymptomatic carotid stenosis and also presents modern approaches to the treatment of these patients. CONCLUSION: Patients younger 75 years old gain an advantage from carotid endarterectomy with small perioperative risk compared to optimal drug therapy and yearly risk of cerebral embolism. Patients with asymptomatic carotid stenosis 80-99% are candidates for carotid endarterectomy due to higher risk of acute cerebrovascular accident at least until more data are available. The choice of the best tactics for a particular patient should be made individually depending on own experience and patient's adherence to therapy and lifestyle correction. The results of the ACTRIS (2025) and CREST-2 (2026) studies are expected to clarify this issue.

Carotid Near-Occlusion: Surgical or Conservative Management? Retrospective Multicenter Study.

BACKGROUND: Carotid near-occlusion (CNO) represents an anatomical-functional condition characterized by severe (more than 90%) internal carotid artery stenosis which can lead to a distal lumen diameter greater or less than 2 mm. CNO can be divided into a less severe subgroup (without lumen full collapse: diameter >2 mm) and a more severe subgroup (with lumen full collapse: diameter <2 mm). The decision for revascularization is still highly debated in Literature. The aim of the present multicenter retrospective study is to analyze the incidence of perioperative (30 days) and follow-up complications in 2 groups of patients with or without distal internal carotid lumen full collapse. METHODS: Between January 2011 and March 2023, in 5 Vascular Surgery Units, 67 patients (49 male, 73% and 18 females, 27%) with CNO underwent carotid endarterectomy: 28 (41.7%) with lumen diameter <2 mm and 39 (58.3%) with diameter >2 mm. 19 patients were symptomatic and 48 asymptomatic. The outcomes considered for comparative analysis were: perioperative neurological and cardiac complications, carotid restenosis or occlusion at follow-up. Both groups were homogeneous in terms of risk factors, morphological features and pharmacological treatments. RESULTS: In the group with lumen <2 mm, 3 perioperative major events (10.7%) occurred (1 ischemic stroke, 1 hemorrhagic stroke, 1 myocardial infarction) and 2 (7.1%) at follow-up (average 11 ± 14.5 months; 1 asymptomatic carotid occlusion, 1 hemodynamic restenosis treated with stenting). No event was recorded in the group with lumen >2 mm. CONCLUSIONS: According to our results CNO patients show different complication risk according to the presence or not of distal lumen collapse. The later seems to play a significant role in perioperative and follow-up complication rate. These results therefore support a surgical treatment only in patients with CNO without lumen full collapse.