Guidelines for carotid endarterectomy. A multidisciplinary consensus statement from the ad hoc Committee, American Heart Association

Seven years of the transcarotid artery revascularization surveillance project, comparison to transfemoral stenting and endarterectomy

OBJECTIVE

This study utilizes the latest data from the Vascular Quality Initiative (VQI), which now encompasses over 50,000 transcarotid artery revascularization (TCAR) procedures, to offer a sizeable dataset for comparing the effectiveness and safety of TCAR, transfemoral carotid artery stenting (tfCAS), and carotid endarterectomy (CEA). Given this substantial dataset, we are now able to compare outcomes overall and stratified by symptom status across revascularization techniques.

METHODS

Utilizing VQI data from September 2016 to August 2023, we conducted a risk-adjusted analysis by applying inverse probability of treatment weighting to compare in-hospital outcomes between TCAR vs tfCAS, CEA vs tfCAS, and TCAR vs CEA. Our primary outcome measure was in-hospital stroke/death. Secondary outcomes included myocardial infarction and cranial nerve injury.

RESULTS

A total of 50,068 patients underwent TCAR, 25,361 patients underwent tfCAS, and 122,737 patients underwent CEA. TCAR patients were older, more likely to have coronary artery disease, chronic kidney disease, and undergo coronary artery bypass grafting/percutaneous coronary intervention as well as prior contralateral CEA/CAS compared with both CEA and tfCAS. TfCAS had higher odds of stroke/death when compared with TCAR (2.9% vs 1.6%; adjusted odds ratio [aOR], 1.84; 95% confidence interval [CI], 1.65-2.06; P < .001) and CEA (2.9% vs 1.3%; aOR, 2.21; 95% CI, 2.01-2.43; P < .001). CEA had slightly lower odds of stroke/death compared with TCAR (1.3% vs 1.6%; aOR, 0.83; 95% CI, 0.76-0.91; P < .001). TfCAS had lower odds of cranial nerve injury compared with TCAR (0.0% vs 0.3%; aOR, 0.00; 95% CI, 0.00-0.00; P < .001) and CEA (0.0% vs 2.3%; aOR, 0.00; 95% CI, 0.0-0.0; P < .001) as well as lower odds of myocardial infarction compared with CEA (0.4% vs 0.6%; aOR, 0.67; 95% CI, 0.54-0.84; P < .001). CEA compared with TCAR had higher odds of myocardial infarction (0.6% vs 0.5%; aOR, 1.31; 95% CI, 1.13-1.54; P < .001) and cranial nerve injury (2.3% vs 0.3%; aOR, 9.42; 95% CI, 7.78-11.4; P < .001).

CONCLUSIONS

Although tfCAS may be beneficial for select patients, the lower stroke/death rates associated with CEA and TCAR are preferred. When deciding between CEA and TCAR, it is important to weigh additional procedural factors and outcomes such as myocardial infarction and cranial nerve injury, particularly when stroke/death rates are similar. Additionally, evaluating subgroups that may benefit from one procedure over another is essential for informed decision-making and enhanced patient care in the treatment of carotid stenosis.

Carotid artery dissection and non-aneurysmal subarachnoid hemorrhage following carotid endarterectomy

Stroke continues to be a major public health issue resulting in high mortality and severe long-term disability. Carotid endarterectomy (CEA) plays an important role in the prevention of ischemic stroke. Complications associated with CEA can be life threatening and prompt recognition is crucial. In this report, we present a patient who presented to the hospital with progressive headache, 2 weeks following CEA. He was neurologically intact and hypertensive. Non-contrast head computed tomography (CT) scan showed convexity subarachnoid hemorrhage (SAH). He was found to have a left internal carotid artery dissection. Patients who present to the hospital following CEA with headache and hypertension benefit from a non-contrast head CT scan. The presence of SAH can be a warning sign of cerebral hyperperfusion syndrome. Carotid artery dissection is also a disease entity that can occur in the post-operative period. Prompt recognition and treatment is crucial for the management of these disease entities.

Outcomes of simultaneous carotid endarterectomy and coronary artery bypass grafting: A single centre experience

OBJECTIVE

Stroke following a coronary artery bypass surgery is a well-known complication often predisposed by carotid artery disease. Perioperative risk of stroke after on-pump cardiac surgery can overall affect 2% of patients. Patients with 80-99% unilateral carotid artery stenosis carry a 4% risk of stroke. Significant carotid artery stenosis is present in 3-10% of patients who are candidates for coronary artery bypass grafting (CABG). Those patients might be considered for either simultaneous or staged carotid endarterectomy and CABG to reduce the risk of stroke and death. The purpose of this study was to evaluate preoperative and intraoperative risk factors for myocardial infarction (MI), stroke and death and assess complications occurring during the early postoperative period after simultaneous CABG/CAE procedure.

METHODS

A single centre retrospective analysis of 134 patients from 2015 to 2019 who underwent simultaneous CABG/CEA was performed. At the same period, a total of 2827 CABG were performed, of which 4.7% were simultaneous interventions. We excluded staged CEA/CABG procedures, off-pump CABG and urgent CABG patients. All patients included in the study met the criteria for elective CABG for triple-vessel or left main trunk symptomatic coronary artery disease (CAD) with asymptomatic >70% carotid stenosis or symptomatic ipsilateral >50% carotid stenosis regardless of the degree of contralateral carotid artery stenosis. Patient demographics, comorbidities and operative details were reviewed. The primary endpoint was to assess the intraoperative and 30-day risk of stroke and death after simultaneous CEA/CABG procedure.

RESULTS

Simultaneous CEA/CABG is effective procedure that can be performed in high-risk symptomatic patients with acceptable results. Predictors of postoperative stroke were smoking (P = 0.011), history of MI (P = 0.046), history of CABG (P = 0.013), and history of stroke/TIA (P = 0.005). Significant risk factors for adverse major postoperative complications after simultaneous CEA/CABG procedure were cardiac arrhythmia (AF or AFL) (P = 0.045), previous MI (P < 0.001), and smoking (P = 0.001).

CONCLUSIONS

Synchronous CEA/CABG procedure can be performed with acceptable results in patients having a high risk of stroke, septuagenarians and older.

Carotid artery stenting without embolic protection: A randomized multicenter trial (the CASWEP trial)

BACKGROUND

Carotid artery stenting (CAS) with a carotid protection device (CPD) has become the standard practice in patients with severe carotid stenosis and high surgical risk. However, the clinical efficacy and safety of CPDs are still controversial issues. We aimed to compare the clinical outcomes of the CAS without CPD with CAS combined with CPD.

METHODS

This is a multicenter randomized prospective study registered with http://clinicaltrials.gov (NCT02781181). After the exclusion, 279 patients were enrolled (139 patients in the CAS with CPD group and 140 patients in the CAS without CPD group). The primary outcome was a combination of peri-procedural in-hospital transient ischemic attack (TIA), ipsilateral stroke, or death. The secondary outcome was new ischemic brain lesions on post-procedural diffusion-weighted magnetic resonance imaging (DW-MRI).

RESULTS

Two patients died in CAS without CPD group, one patient died in CAS with CPD group. TIA was only seen in patients who underwent CAS under protection (n = 5). The combined primary outcome of TIA, ipsilateral stroke, and death rate was not different between groups (5.7% vs. 2.8%; p = 0.254). New defects were noted on the post-procedural DW-MRI in 28% of patients in the CPD group and 27% of patients in the no CPD group (p = 0.881).

CONCLUSIONS

This study suggests that CAS without CPD is not associated with higher rates of peri-procedural TIA, stroke, and death or new ischemic brain lesions on post-procedural DW-MRI compared to CAS with CPD in selected symptomatic and asymptomatic patients with significant carotid artery stenosis provided that there is no visible thrombus.

Carotid stenting: Does stent design matter?

BACKGROUND

Carotid artery stenting (CAS) is considered an important tool in carotid revascularization. Carotid artery stenting is usually performed by using self-expandable stent with different designs. The stent design influences many physical characteristics. Also, it may affect the complication rate with special relevance to perioperative stroke, hemodynamic instability, and late restenosis.

METHODS

This study comprised all consecutive patients who underwent carotid artery stenting for atherosclerotic carotid stenosis from March 2014 to May 2021. Both symptomatic patient and asymptomatic patients were included. Patients with a symptomatic carotid stenosis of ≥50% or asymptomatic carotid stenosis of ≥60% were selected for carotid artery stenting . Patients with fibromuscular dysplasia and acute or unstable plaque were not included. Variables of clinical relevance were tested in multivariable analysis using binary logistic regression model.

RESULTS

A total of 728 patients were enrolled. The majority of this cohort was asymptomatic (578/728, 79.4%), while 150/728 (20.6%) were symptomatic. The mean degree of carotid stenosis was 77.82 ± 4.73%, with a mean plaque length of 1.76 ± 0.55 cm. A total of 277 (38%) patients were treated with Xact® Carotid Stent System. Successful carotid artery stenting was achieved in 698 (96%) of patients. Of these patients, stroke rate in symptomatic patients was nine (5.8%), while in asymptomatic patients was 20 (3.4%). In a multivariable analysis, the open-cell carotid stent was not associated with a differential risk for combined acute and sub-acute neurologic complications as compared with closed-cell stents. Patients treated with open cell stents had a significantly lower rate of procedural hypotension (P 0.0188) at bivariate analysis.

CONCLUSION

Carotid artery stenting is considered a safe alternative to CEA that can be used in selected average surgical risk patient. Different stent designs can affect the rate of major adverse events in carotid artery stenting patients, but further studies are necessary with avoiding different bias to study the effect of different stent designs.

Carotid Endarterectomy Surgeries: A Multimodality Intraoperative Neurophysiological Monitoring Approach

Patients with untreated carotid artery stenosis remain at high risk for stroke. Carotid endarterectomy (CEA) is a surgical procedure for the treatment of symptomatic and severe asymptomatic carotid stenosis. A small percentage of patients who do not have good collateral circulation are at high risk of cerebral ischemia during the cross-clamping of the carotid artery. Aspects of CEA, such as cross-clamping and routine shunting, can also carry the risk of perioperative stroke through dislodgement of emboli causing thrombosis, therefore, selective shunting is highly recommended during the CEA procedure. A multimodality approach of intraoperative neurophysiological monitoring (IONM) techniques such as somatosensory evoked potential (SSEP) and electroencephalography (EEG) can be used to monitor cerebral perfusion throughout the duration of the surgery and to predict the need for a selective shunt after cross-clamping. Additional use of transcranial Doppler (TCD) in the multimodality approach can aid in visualizing the cerebral blood flow and detecting any microemboli that may also cause a stroke. A multimodality IONM approach has been reported as more sensitive and specific for predicting and minimizing any postoperative neurological deficits.

Restenosis rates in patients with ipsilateral carotid endarterectomy and contralateral carotid artery stenting

Purpose

We aimed to evaluate the long-term outcome of carotid endarterectomy (CEA) and carotid artery stenting (CAS) in patients who underwent both procedures on different sides.

Methods

In this single-center retrospective study (2001–2019), 117 patients (men, N = 78; median age at CEA, 64.4 [interquartile range {IQR}, 57.8–72.2] years; median age at CAS, 68.8 [IQR, 61.0–76.0] years) with ≥50% internal carotid artery stenosis who had CEA on one side and CAS on the other side were included. The risk of restenosis was estimated by treatment adjusted for patient and lesion characteristics.

Results

Neurological symptoms were significantly more common (41.9% vs 16.2%, P<0.001) and patients had a significantly shorter mean duration of smoking (30.2 [standard deviation {SD}, 22.2] years vs 31.8 [SD, 23.4] years, P<0.001), hypertension (10.1 [SD, 9.8] years vs 13.4 [SD, 9.1] years, P<0.001), hyperlipidemia (3.6 [SD, 6.6] years vs 5.0 [SD, 7.3] years, P = 0.001), and diabetes mellitus (3.9 [SD, 6.9] years vs 5.7 [SD, 8.9] years, P<0.001) before CEA compared to those before CAS. While the prevalence of heavily calcified stenoses on the operated side (25.6% vs 6.8%, P<0.001), the incidence of predominantly echogenic/echogenic plaques (53.0% vs 70.1%, P = 0.011) and suprabulbar lesions (1.7% vs 22.2%, P<0.001) on the stented side was significantly higher. Restenosis rates were 10.4% at 1 year, 22.3% at 5 years, and 33.7% at the end of the follow-up (at 11 years) for CEA, while these were 11.4%, 14.7%, and 17.2%, respectively, for CAS. Cox regression analysis revealed a significantly higher risk of restenosis (hazard ratio [HR], 1.80; 95% confidence interval [CI], 1.05–3.10; P = 0.030) for CEA compared to that for CAS. After adjusting for relevant confounding factors (smoking, hypertension, diabetes mellitus, calcification severity, plaque echogenicity, and lesion location), the estimate effect size materially did not change, although it did not remain statistically significant (HR, 1.85; 95% CI, 0.95–3.60; P = 0.070).

Conclusion

Intra-patient comparison of CEA and CAS in terms of restenosis tilts the balance toward CAS.

A survey of Canadian surgeons on the indications for home care nursing following vascular surgery

Background

Recent evidence suggests that home care nursing is variably prescribed after vascular surgery, and may reduce emergency department visits and hospital readmissions. We therefore sought to characterize the indications for home care nursing following vascular surgery from the surgeon’s perspective.

Methods

An online survey was distributed to the 141 members of the Canadian Society for Vascular Surgery with questions related to home care nursing after carotid endarterectomy (CEA), endovascular aortic aneurysm repair (EVAR), open abdominal aortic aneurysm (AAA) repair and open or hybrid revascularization for peripheral arterial disease (PAD). We included all questionnaires in our analysis; the frequency denominator changes according to the number of respondents who completed each survey item.

Results

There were 46 survey respondents (33% of 141) from across the country. A total of 28 (62% of 45) worked in a teaching hospital. Home care nursing was routinely prescribed by 5%, 10%, 31% and 41% of respondents following CEA, EVAR, open AAA repair and open or hybrid revascularization for PAD, respectively. Across all procedure types, the same procedure-related criteria were most often deemed to warrant a prescription for home care nursing: surgical site infection, wound complications (e.g., open wound, lymphatic leak) and use of negative-pressure wound therapy. Across all procedure types, lack of social support, physical frailty and cognitive impairment were most frequently identified as patient-specific considerations for prescribing home care nursing. Few respondents reported restrictions or standards that informed their prescribing practice.

Conclusion

Most surgeon respondents agreed on the indications for home care nursing after vascular surgery. However, evidence-based standards to guide patient selection for home care nursing after vascular surgery are needed.

The conundrum of asymptomatic carotid stenosis-determinants of decision and evidence

Management of asymptomatic carotid disease continues to challenge medical practice and present evidence is often conflicting. Stroke is a significant burden in Public Health and 11% to 15% appear as first neurologic event associated with asymptomatic carotid stenosis. Randomized trials provided support for Guidelines and Recommendations to intervene on asymptomatic stenosis, but at a known cost of a high number of unnecessary operations. Conflicting evidence from natural history studies and the widespread use of proper medical management including risk factors control, lowering-lipid drugs and strict control of arterial hypertension have reduced the incidence of strokes associated to asymptomatic carotid disease challenging established practice. Need to identify vulnerable lesions prone to develop thromboembolic brain events and also vulnerable patients at a higher risk of stroke is necessary and essential to further improve effectiveness of our interventions. After review of published literature on natural history of asymptomatic carotid stenosis, diagnostic methods to identify plaque vulnerability and present-day results of both endarterectomy and stenting, a strategy for management of asymptomatic carotid stenosis is suggested aiming to reduce unnecessary interventions and effectively contribute to stroke prevention.

MicroRNAs as sentinels and protagonists of carotid artery thromboembolism

Stroke is the leading cause of serious disability in the world and a large number of ischemic strokes are due to thromboembolism from unstable carotid artery atherosclerotic plaque. As it is difficult to predict plaque rupture and surgical treatment of asymptomatic disease carries a risk of stroke, carotid disease continues to present major challenges with regard to clinical decision-making and revascularization. There is therefore an imminent need to better understand the molecular mechanisms governing plaque instability and rupture, as this would allow for the development of biomarkers to identify at-risk asymptomatic carotid plaque prior to disease progression and stroke. Further, it would aid in creation of therapeutics to stabilize carotid plaque. MicroRNAs (miRNAs) have been implicated as key protagonists in various stages of atherosclerotic plaque initiation, development and rupture. Notably, they appear to play a crucial role in carotid artery thromboembolism. As the molecular pathways governing the role of miRNAs are being uncovered, we are learning that their involvement is complex, tissue- and stage-specific, and highly selective. Notably, miRNAs can be packaged and secreted in extracellular vesicles (EVs), where they participate in cell-cell communication. The measurement of EV-encapsulated miRNAs in the circulation may inform disease mechanisms occurring in the plaque itself, and therefore may serve as sentinels of unstable plaque as well as therapeutic targets.

[Surgical policy of managing patients with concomitant atherosclerotic lesions of the internal and common carotid arteries]

AIM

The purpose of this study was to investigate the natural course of stenosis of the common carotid artery (CCA) after carotid endarterectomy, as well as the long-term outcomes of various methods of reconstruction of the internal carotid artery (ICA) in patients with extended atherosclerotic lesions.

PATIENTS AND METHODS

Presented herein are the remote retrospective and prospective results of carotid endarterectomy in a total of 78 patients with concomitant atherosclerotic lesions of carotid arteries. Depending on the degree of CCA stenosis, the patients were divided into 2 groups. Group One (n=25): stenosis of the internal carotid artery (ICA) of more than 70% and haemodynamically insignificant (30-35% stenosis) but extended (from 3.0 to 5.0 cm (Q1, Me, Q3); 3.5 cm, 4.0 cm, 5.0 cm) stenosis of the CCA. These patients underwent carotid endarterectomy (CEA) from the ostium of the ICA, during which an atherosclerotic plaque was not completely removed from the CCA because the stenosis was extended but haemodynamically insignificant. Group Two (n=53): stenosis of the ICA of more than 70% and haemodynamically significant, extended (from 7.0 to 10.0 cm (Q1, Me, Q3); 7.5 cm, 8.0 cm, 9.0 cm) stenosis of the CCA. The patients of this group were subjected to various methods of operative intervention on the ICA and CCA: carotid endarterectomy (ECA) combined with open endarterectomy from the CCA with plasty using the primary suture (n=23); carotid endarterectomy and alloreconstruction of the CCA (n=10); simultaneous eversion endarterectomy from the ICA and CCA (n=20). The remote period of follow up of patients ranged from 14 to 24 months ((Q1, Me, Q3; 19 months, 22 months, 24 months). The differences were statistically insignificant (Mann-Whitney U-test, p=0.881).

RESULTS

In the remote postoperative period, 32% of Group One patients after previously performed carotid endarterectomy were found to have an increase in the degree of stenosis of the CCA up to a haemodynamically significant one (70% and more), thus suggesting progression of the atherosclerotic process. In Group Two patients, after plasty of the CCA with the primary suture, 21.7% of patients were diagnosed as having restenosis of the reconstruction zone up to 30%, with no neurological deficit. 20% of patients after carotid endarterectomy and alloreconstruction of the CCA were diagnosed as having restenosis of the reconstruction zone more than 70% and acute impairment of cerebral circulation with a lethal outcome. The patients after simultaneous eversion endarterectomy form the ICA and CCA in the intraoperative and postoperative periods had neither restenosis of the reconstruction zone nor neurological deficit.

CONCLUSION

32% of patients after previously performed carotid endarterectomy with the presence of extended, but haemodynamically insignificant stenosis of the CCA (30-35% stenosis) in the postoperative period were found to have progression of the atherosclerotic lesion in the form of an increased degree of stenosis up to haemodynamically significant (more than 70%), thus requiring repeat reconstructive operation. Therefore, in patients presenting with concomitant atherosclerotic lesions of the carotid arteries it is appropriate to carry out operative intervention simultaneously on the ICA and CCA, which would make it possible to considerably improve the remote postoperative results of reconstructive interventions on the carotid basin in this cohort of patients. A comparative study of the outcomes of various methods of reconstruction of carotid arteries in patients with concomitant atherosclerotic lesions of the ICA and CCA demonstrated that simultaneous eversion endarterectomy from the ICA and CCA resulted in good postoperative parameters: absence of restenosis and neurological deficit in the remote period of follow up.

Significant changes of the choroid in patients with ocular ischemic syndrome and symptomatic carotid artery stenosis

Purpose

To evaluated the changes in choroidal vasculature in patients with ocular ischemic syndrome (OIS) and in the ipsilateral eyes of patients with symptomatic carotid artery stenosis (CAS)

Method

A total of 50 patients (15 patients with OIS, 10 patients with symptomatic CAS, 25 patients of age-and sex-matched control group) were included, and the medical records were retrospectively reviewed. The mean subfoveal choroidal thickness (SFCT) of each eye was measured, and binary images of the choroid were evaluated to compare the mean choroidal area and the luminal area.

Results

The mean SFCT was 170.5±75.3 μm in the eyes with OIS, 154.8±62.9 μm in the ipsilateral eyes with symptomatic CAS, and 277.5±73.2 μm in the right eyes of the control group patients (P<0.001). The mean choroidal area was 494,478.6±181,846.2 μm2 in the eyes with OIS, 453,750.0±196,725.8 μm2 in the ipsilateral eyes with symptomatic CAS, and 720,520±281,319.5 μm2 in the control group eyes (P = 0.036). The mean luminal area was 333,185.7±112,665.9 μm2 in the eyes with OIS, 313,983.3±132,032.1 μm2 in the ipsilateral eyes with symptomatic CAS, and 480,325.0±185,112.6 μm2 in the control group eyes (P = 0.046). The mean SFCT, mean choroidal area, and mean luminal area were significantly smaller in the eyes with OIS (P = 0.017, P = 0.005, and P = 0.004, respectively), and those with symptomatic CAS (P = 0.020, P = 0.016, and P = 0.021, respectively) than in the unaffected contralateral eyes. There were no significant differences between the eyes in the control group (P = 0.984, P = 284, and P = 0.413, respectively).

Conclusion

The mean SFCT, mean choroidal area, and mean luminal area were significantly thinner in the eyes with OIS and the ipsilateral eyes with symptomatic CAS, compared with the control group eyes. The eyes with OIS and those with symptomatic CAS had significantly thinner SFCT, and smaller choroidal area and luminal area than the unaffected contralateral eyes. Choroid may reflect the vascular status of the carotid artery, indicated by choroidal thinning and decreasing choroidal area, especially luminal area.

Meta-analysis of the procedural risks of carotid endarterectomy and carotid artery stenting over time

Background

Stroke/death rates within 30 days of carotid endarterectomy (CEA) and carotid artery stenting (CAS) in RCTs inform current clinical guidelines. However, the risks may have changed in recent years with wider use of effective stroke prevention therapies, especially statins, improved patient selection and growing operator expertise. The aim of this study was to investigate whether the procedural stroke/death risks from CEA and CAS have changed over time.

Methods

MEDLINE and Embase were searched systematically from inception to May 2016 for observational cohort studies of CEA and CAS. Studies included reported on more than 1000 patients, with 30‐day outcomes after the procedure according to patients' symptom status (recent stroke or transient ischaemic attack). Restricted maximum likelihood random‐effects and meta‐regressions methods were used to synthesize procedural stroke/death rates of CEA and CAS according to year of study recruitment completion.

Results

Fifty‐one studies, including 223 313 patients undergoing CEA and 72 961 undergoing CAS, were reviewed. Procedural stroke/death risks of CEA decreased over time in symptomatic and asymptomatic patients. Risks were substantially lower in studies completing recruitment in 2005 or later, both in symptomatic (5·11 per cent before 2005 versus 2·68 per cent from 2005 onwards; P = 0·002) and asymptomatic (3·17 versus 1·50 per cent; P < 0·001) patients. Procedural stroke/death rates of CAS did not change significantly over time (4·77 per cent among symptomatic and 2·59 per cent among asymptomatic patients). There was substantial heterogeneity in event rates and recruitment periods were long.

Conclusions

Risks of procedural stroke/death following CEA appear to have decreased substantially. There was no evidence of a change in stroke/death rates following CAS.

Endarterectomy outcomes improving

Patterns of Acute Ischemic Strokes After Carotid Endarterectomy and Therapeutic Implications

AIM

Acute ischemic strokes following surgical treatment of carotid stenosis lead to substantial disability and mortality, and vascular mechanisms underlying their development are not fully elucidated. The goal of this study was to analyze the topographic patterns of acute ischemic stroke following carotid endarterectomy (CEA) on diffusion-weighted and perfusion-weighted magnetic resonance imaging (MRI).

MATERIAL AND METHODS

Data were retrospectively collected from consecutive patients who underwent CEA and developed postoperative acute ischemic stroke. Based on the MRI data sets, the lesion patterns of acute stoke were characterized. Morphology of the circle of Willis, the 3-D time-of-flight (3D-TOF) of the cerebral arteries, and status of the carotid circulation were also analyzed in order to determine the vascular mechanisms involved in stroke development.

RESULTS

Between January 2008 and May 2015, 821 patients were treated surgically for a symptomatic or asymptomatic carotid stenosis at the University Hospital of Nice. Nineteen (2.3%) patients had an acute ischemic stroke after surgery. Among them, 11 (57.9%) patients had a territorial infarction and 8 (42.1%) patients had an internal watershed infarction, cortical watershed infarction, or mixed border zone infarction. According to imaging data sets, embolic mechanism of stroke was reported for 12 (63.2%) patients, hemodynamic mechanism for 2 (10.5%) patients, and mixed mechanism for 5 (26.3%) patients. An asymmetry on 3D-TOF was observed in 60% and 50% of patients with hemodynamic and mixed stroke and in 25% of patients with embolic stroke. The latter 2 patients with embolic stroke underwent successful mechanical thrombectomy using stent-retriever devices.

CONCLUSION

In this cohort, embolic mechanism leading to postoperative stroke was more frequently observed than hemodynamic mechanism. Immediate characterization of the cerebral lesion by postoperative brain MRI is of utmost importance because it may rapidly identify patients eligible for treatments such as mechanical thrombectomy.

Point-of-Care-Testing in Acute Stroke Management: An Unmet Need Ripe for Technological Harvest

Stroke, the second highest leading cause of death, is caused by an abrupt interruption of blood to the brain. Supply of blood needs to be promptly restored to salvage brain tissues from irreversible neuronal death. Existing assessment of stroke patients is based largely on detailed clinical evaluation that is complemented by neuroimaging methods. However, emerging data point to the potential use of blood-derived biomarkers in aiding clinical decision-making especially in the diagnosis of ischemic stroke, triaging patients for acute reperfusion therapies, and in informing stroke mechanisms and prognosis. The demand for newer techniques to deliver individualized information on-site for incorporation into a time-sensitive work-flow has become greater. In this review, we examine the roles of a portable and easy to use point-of-care-test (POCT) in shortening the time-to-treatment, classifying stroke subtypes and improving patient's outcome. We first examine the conventional stroke management workflow, then highlight situations where a bedside biomarker assessment might aid clinical decision-making. A novel stroke POCT approach is presented, which combines the use of quantitative and multiplex POCT platforms for the detection of specific stroke biomarkers, as well as data-mining tools to drive analytical processes. Further work is needed in the development of POCTs to fulfill an unmet need in acute stroke management.

Relationship between carotid plaque surface morphology and perfusion: a 3D DCE-MRI study

Objective

This study aims to explore the relationship between plaque surface morphology and neovascularization using a high temporal and spatial resolution 4D contrast-enhanced MRI/MRA sequence.

Materials and methods

Twenty one patients with either recent symptoms or a carotid artery stenosis ≥40% were recruited in this study. Plaque surface morphology and luminal stenosis were determined from the arterial phase MRA images. Carotid neovascularization was evaluated by a previously validated pharmacokinetic (PK) modeling approach. K^trans (transfer constant) and v_p (partial plasma volume) were calculated in both the adventitia and plaque.

Results

Image acquisition and analysis was successfully performed in 28 arteries. Mean luminal stenosis was 44% (range 11–82%). Both adventitial and plaque K^trans in ulcerated/irregular plaques were significantly higher than smooth plaques (0.079 ± 0.018 vs. 0.064 ± 0.011 min⁻¹, p = 0.02; 0.065 ± 0.013 vs. 0.055 ± 0.010 min⁻¹, p = 0.03, respectively). Positive correlations between adventitial K^trans and v_p against stenosis were observed (r = 0.44, p = 0.02; r = 0.55, p = 0.01, respectively).

Conclusion

This study demonstrates the feasibility of using a single sequence to acquire both high resolution 4D CE-MRA and DCE-MRI to evaluate both plaque surface morphology and function. The results demonstrate significant relationships between lumen surface morphology and neovascularization.

Carotid Stenting for Radiation-Induced Extracranial Carotid Artery Occlusive Disease: Efficacy and Midterm Outcomes

Purpose:

To investigate the immediate and midterm results of carotid stenting for severe radiation-induced extracranial carotid artery disease.

Methods:

Between April 1998 and May 2002, 16 patients (15 men; mean age 64±8 years, range 48–72) presented with 18 severe radiation-induced carotid stenoses in the internal carotid artery (n=3), common carotid artery (n=7), and both vessels (n=8). Thirteen (76%) patients were symptomatic; the mean degree of carotid stenosis was 85%±10% (range 70%–95%). An independent neurological specialist assessed perioperative neurological complications before and after treatment. The patients were followed prospectively for at least 12 months by clinical examination and serial duplex ultrasound scanning. Restenosis was defined as a diameter reduction >50%.

Results:

Of 18 stent procedures attempted (2 staged), 1 was abandoned owing to failure to pass the guidewire across a tight lesion (94% technical success by intent to treat). In the 17 successfully completed procedures, 17 Wallstents and 4 SMART stents were deployed with satisfactory anatomical results. One postoperative stroke occurred as a result of thromboembolism to the ipsilateral middle cerebral artery and led to hospital death (5.9% combined stroke and death rate). One transient ischemic attack occurred (11.6% neurological event rate). With a median 30-month follow-up (range 5–55), 3 (17.6%) recurrent stenoses (>50%) were detected on duplex scan; 1 repeat angioplasty was performed. No new neurological event has been detected.

Conclusions:

Carotid stenting may be performed in patients with irradiation-induced carotid stenosis with acceptable risks and midterm durability.

History and Current Status of Endovascular Management for the Extracranial Carotid and Supra-Aortic Vessels

Few procedures in the history of medicine have been more controversial than carotid artery stenting (CAS) for the management of carotid artery occlusive disease. Introduced just as the randomized trials were establishing carotid endarterectomy as the gold standard for carotid interventions, CAS has finally reached the point in its development when dedicated stenting systems are being tested in randomized clinical trials. Assisted by the concomitant use of distal protection devices, CAS has shown equipoise with endarterectomy in terms of safety at 30 days. This review summarizes the completed and ongoing CAS trials and the applications of endovascular techniques in the supra-aortic vessels.

Reoperation for Recurrent Carotid Stenosis: A Ten-Year Experience

Owing to the supposed risks of reoperation, carotid stenting has been proposed as a treatment for carotid restenosis. The purpose of this study is to determine the safety and efficacy of carotid reoperation. From March 1988 to March 1997, 40 patients, 18 men and 22 women (mean age: 65 years) underwent a total of 43 redo carotid procedures by our group. Two patients had both sides repaired and one required a second reoperation. Symptomatic recurrent carotid stenosis (>70%) was the indication in 25 reoperations and asymptomatic high-grade stenosis (>80%) was the indication in 18. The initial operation in 35 reoperations was carotid endarterectomy (CEA) with primary closure and in eight it was CEA with a prosthetic patch. The interval to recurrence was less in the 24 reoperations in patients who had myointimal hyperplasia (21 months) compared with 17 reoperations in patients with recurrent atherosclerosis (90 months). The other two reoperations were for an intimal flap 2 months after the original CEA, and for operative dilation of fibromuscular dysplastic bands missed on magnetic resonance angiography (MRA), distal to the site of a previous CEA.

The technique of reoperation included redo CEA in two, CEA with vein patch in eight, CEA with prosthetic patch in 22, vein interposition graft in five, and prosthetic interposition graft in five. In addition, operative dilation with an arterial dilator was used in one reoperation.

No perioperative strokes or deaths occurred other than one patient who died from cardiac complications following combined CEA and coronary artery bypass grafting. Operative morbidity consisted of pneumonia in one patient, reversible cranial nerve injury in four, and hematoma requiring evacuation in two. During follow-up (mean: 34 months), carotid occlusion resulted in a mild stroke in one patient, there were 10 late deaths not related to carotid disease, one patient required a reoperation, and three patients were lost to follow-up.

The authors conclude that reoperation for recurrent carotid stenosis, using standard vascular techniques, is both safe and effective; it should continue to be the mainstay of treatment when intervention is required.

Endovascular Stents for Carotid Artery Occlusive Disease

Purpose:

To study the feasibility and safety of endovascular stenting of cervical carotid artery stenosis.

Methods:

Between April 1994 and May 1997, 108 consecutive patients (58 men; mean age 70.1 years) with ≥ 70% carotid stenosis were treated with percutaneous stent implantation under a protocol that featured independent neurological review. Forty-four percent were asymptomatic. Over half the lesions (59%) were in the internal carotid artery; the mean stenosis was 86%. Palmaz stents were implanted without cerebral protection following preliminary balloon dilation; two Wallstents were used in long lesions.

Results:

Carotid stents were successfully placed in 108 of 114 (95%) lesions. Of the 6 technical failures, 5 were access related and 1 was due to seizures during balloon dilation. Two major (1.8%) and 2 minor (1.8%) strokes occurred (3.7% stroke rate for 108 patients; 3.5% in 114 procedures), all in symptomatic patients, one of whom died. There were 5 (4.4%) transient ischemic attacks and 2 (1.8%) brief seizure episodes during dilation. One patient died of a cardiac event on day 20. The all stroke or death rate was 5.3% based on 114 arteries at risk (5.6% in 108 patients). In the mean 6-month follow-up (range 1 to 36) of 97 eligible patients, 3 (3.1%) died from unrelated causes. There was 1 restenosis (1.0%) from a stent compression, which was successfully redilated. There were no neurological sequelae, cranial palsies, or cases of stent or vessel thrombosis in follow-up.

Conclusions:

The use of stents in the treatment of cervical carotid occlusive disease appears feasible, effective in the short term, and without excessive risk of periprocedural stroke.

Carotid Revascularization Using Endarterectomy or Stenting Systems (CARESS): Phase I Clinical Trial

Purpose:

To determine whether carotid stenting with embolic protection is equivalent to carotid endarterectomy (CEA) in a broad risk population of patients with symptomatic and asymptomatic carotid stenosis.

Methods:

A prospective, multicenter Phase I trial was conducted comparing standard CEA to carotid stenting systems (CSS) in patients with symptomatic (≥50%) and asymptomatic (≥75%) carotid stenosis. Patients were enrolled using selection criteria reflective of broad clinical practice. The enrollment ratio at each clinical site was designed to be 2:1 (CEA to CSS) to achieve a planned enrollment of 450 patients: 300 in the CEA arm and 150 in the CSS cohort, which would ensure adequate precision with a coefficient of variation ≤0.35. The primary endpoint for comparison was 30-day all-cause mortality and nonfatal stroke.

Results:

Between April 2001 and December 2002, 14 clinical sites enrolled 439 patients, of which 397 (247 men; mean age 71 years, range 44–89) were treated: 254 with CEA and 143 patients with CSS (ratio 1.8 to 1.0). More than 90% of patients had >75% stenosis; ∼68% of patients were asymptomatic. There were no significant differences in baseline patient characteristics between the treatment groups with the exception of a more frequent history of prior CEA (30% CSS versus 11% for CEA, p<0.0001) and prior carotid stent placement in the CSS group (6% versus 0% for CEA, p = 0.0002). There was no significant difference in the 30-day combined all-cause mortality and stroke rate by Kaplan-Meier estimate between CEA (2%) and CSS (2%). There was no significant difference in the secondary endpoint of combined 30-day all-cause mortality, stroke, and myocardial infarction between CEA (3%) and CSS (2%).

Conclusions:

This study suggests that the 30-day risk of stroke or death following carotid stenting with cerebral protection is equivalent to standard carotid endarterectomy in a broad risk population of patients with carotid stenosis.

Determinants of In-Stent Restenosis after Carotid Angioplasty: A Case-Control Study

Purpose:

To report a retrospective study that sought to identify clinical factors contributing to the development of in-stent restenosis in the carotid arteries, to profile the patients at greatest risk, and to review the treatment modalities evolved from our experience.

Methods:

Between December 2000 and April 2003, 195 carotid angioplasty/stenting (CAS) procedures (12 bilateral) were performed in 183 patients (131 men; median age 65.9 years, interquartile range 55.2–72.7). Stenting for de novo stenoses was performed in 119 (61%) carotid arteries; 76 (39%) vessels were treated for postsurgical restenosis. Nearly two thirds of the patients (117, 64%) were symptomatic. Patients were evaluated at 3 and 6 months and at 6-month intervals thereafter with duplex ultrasonography. Angiography was used to confirm any recurrent lesion detected on the ultrasound scan.

Results:

Overall perioperative neurological complications included 4 (2.2%) minor strokes, 1 (0.5%) intracranial hemorrhage, and 1 (0.5%) major stroke; both patients with major neurological complications died at 5 and 12 days, respectively, after the procedure. During the 12.5-month follow-up (range 0–27.2), 3 non-procedure-related late deaths and another 9 (4.9%) neurological events occurred (2 strokes and 7 transient ischemic attacks). In-stent restenosis after CAS was present in 10 (5.2%) of 193 carotid arteries (9/181 patients) in follow-up; all but 1 artery had been treated for postsurgical restenosis. All lesions were treated secondarily with endovascular procedures. Statistical analysis demonstrated that postsurgical restenosis was the only predictive factor for the development of in-stent restenosis (OR 15.5, 95% CI 2.05 to 125.6, p = 0.001) in this cohort.

Conclusions:

The present study, far from being exhaustive on the subject, indicates that patients who develop restenosis after carotid endarterectomy are also prone to develop restenosis after CAS; moreover, although strongly recommended for postsurgical restenosis, CAS carries a greater risk of in-stent restenosis in this subgroup, thus reducing the benefits of this procedure.

Selection of Treatment for Patients with Carotid Artery Disease: Medication, Carotid Endarterectomy, or Carotid Artery Stenting

Patients presenting with atherosclerosis of the extracranial carotid arteries may be offered carotid endarterectomy (CEA), carotid artery stenting (CAS), or medical therapy to reduce their risk of stroke. In many cases, the choice between treatment modalities remains controversial.

An algorithm based on patients' neurologic symptoms, comorbidities, limiting factors for CAS and CEA, and personal preferences was developed to determine the optimal treatment in each case. This algorithm was then employed to determine therapy in 308 consecutive patients presenting to a single institution during one calendar year.

Ninety-five (30.8%) patients presented with an asymptomatic carotid stenosis of more than 80% and 213 (69.2%) with a symptomatic stenosis of more than 50%. According to our algorithm, 59 (62.1%) of the 95 asymptomatic patients received CAS, 20 (21.1%) received CEA, and 16 (16.8%) received medical therapy. All symptomatic patients underwent intervention; 153 (71.8%) were treated with CAS and 60 (28.2%) with CEA. Combined 30-day stroke and death rates after CAS were 1.7% in asymptomatic patients and 2.6% in symptomatic patients. After CEA, these rates were 0% and 3.3%, respectively.

Careful selection of treatment modality according to predetermined criteria can result in improved outcomes.

Carotid Endarterectomy: The Gold Standard

Carotid endarterectomy has been firmly established as the gold standard of therapy for symptomatic and asymptomatic patients with severe carotid stenosis, provided surgical complication rates are within prescribed limits. The procedure-related risk of stroke/death should be < 3% in asymptomatic patients and < 6% in symptomatic patients. New investigational therapies such as balloon angioplasty and stenting for carotid stenosis should be evaluated against the same standard.

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.

Relationships between 2-Year Survival, Costs, and Outcomes following Carotid Endarterectomy in Asymptomatic Patients in the Vascular Quality Initiative

BACKGROUND

Carotid endarterectomy (CEA) for asymptomatic patients with limited life expectancy may not be beneficial or cost-effective. The purpose of this study was to examine relationships among survival, outcomes, and costs within 2 years following CEA among asymptomatic patients.

METHODS

Prospectively collected data from 3097 patients undergoing CEA for asymptomatic disease from Vascular Quality Initiative VQI registry were linked to Medicare. Models were used to identify predictors of 2-year mortality following CEA. Patients were classified as low, medium, or high risk of death based on this model. Next, we examined costs related to cerebrovascular care, occurrence of stroke, rehospitalization, and reintervention within 2 years following CEA across risk strata.

RESULTS

Overall, 2-year mortality was 6.7%. Age, diabetes, smoking, congestive heart failure (CHF), chronic obstructive pulmonary disease, renal insufficiency, absence of statin use, and contralateral internal carotid artery (ICA) stenosis were independently associated with a higher risk of death following CEA. In-hospital costs averaged $7500 among patients defined as low risk for death, and exceeded $10,800 among high risk patients. Although long-term costs related to cerebrovascular disease were 2 times higher in patients deemed high risk for death compared with low risk patents ($17,800 vs. $8800, P = 0.001), high risk of death was not independently associated with a high probability of high cost. Predictors of high cost at 2 years were severe contralateral ICA stenosis, dialysis dependence, and American Society for Anesthesia Class 4. Both statin use and CHF were protective of high cost.

CONCLUSIONS

Greater than 90% of patients undergoing CEA live long enough to realize the benefits of their procedure. Moreover, the long-term costs are supported by the effectiveness of this procedure at all levels of patient risk.

In Vivo Validation of Simultaneous Non-Contrast Angiography and intraPlaque Hemorrhage (SNAP) Magnetic Resonance Angiography: An Intracranial Artery Study

Objectives

Simultaneous Non-contrast Angiography and intraPlaque hemorrhage (SNAP) technique was recently proposed for joint MRA and intraplaque hemorrhage (IPH) imaging. The purpose of this study is to validate SNAP’s MRA performance in patients with suspected intracranial artery disease.

Methods

SNAP and time-of-flight (TOF) techniques with matched field of view and resolution were applied on 15 patients with suspected intracranial artery disease. Both techniques were evaluated based on their detection of luminal stenosis of bilateral middle cerebral arteries (MCA) and the delineation of smallest visible branches (SVB) of the MCA. Statistical analysis was conducted on the artery level.

Results

The SNAP MRA was found to provide similar stenosis detection performance when compared with TOF (Cohen’s κ 0.79; 95% Confidence Interval: 0.56–0.99). For the SVB comparison, SNAP was found to provide significantly better small artery delineation than TOF (p = 0.017). Inter-reader reproducibility for both measurements on SNAP was over 0.7. SNAP also detected IPH lesions on 13% of the patients.

Conclusions

The SNAP technique’s MRA performance was optimized and compared against TOF for intracranial artery atherosclerosis imaging and was found to provide comparable stenosis detection accuracy. Along with its IPH detection capability, SNAP holds the potential to become a first-line screening tool for high risk intracranial atherosclerosis disease evaluation.

Fast simultaneous noncontrast angiography and intraplaque hemorrhage (fSNAP) sequence for carotid artery imaging

PURPOSE

To propose a fast simultaneous noncontrast angiography and intraplaque hemorrhage (fSNAP) sequence for carotid artery imaging.

METHODS

The proposed fSNAP sequence uses a low-resolution reference acquisition for phase-sensitive reconstruction to speed up the scan, and an inversion recovery acquisition with arbitrary k-space filling order to generate similar contrast to conventional SNAP. Four healthy volunteers and eight patients were recruited to test the performance of fSNAP in vivo. The lumen area quantification, muscle-blood CNR, IPH-blood CNR, lumen SNR, and standard deviation and intraplaque hemorrhage (IPH) detection accuracy were compared between fSNAP and SNAP.

RESULTS

By using a low-resolution reference acquisition with 1/4 matrix size of the full-resolution reference scan, the scan time of fSNAP was 37.5% less than that of SNAP. A high agreement of lumen area measurement (ICC = 0.97, 95% CI: 0.96-0.99) and IPH detection (Kappa = 1) were found between fSNAP and SNAP. Also, no significant difference was found for muscle-blood CNR (P = 0.25), IPH-blood CNR (P = 0.35), lumen SNR (P = 0.60), and standard deviation (P = 0.46) between the two techniques.

CONCLUSION

The feasibility of fSNAP was validated. fSNAP can improve the imaging efficiency with similar performance to SNAP on carotid artery imaging. Magn Reson Med 77:753-758, 2017. © 2016 International Society for Magnetic Resonance in Medicine.

Increased FGF23 serum level is associated with unstable carotid plaque in type 2 diabetic subjects with internal carotid stenosis

Background

The object of this study was to investigate the potential role of FGF23 on plaque stability in type 2 diabetic patients with internal carotid artery stenosis.

Methods

In this retrospective observational study, we analyzed FGF23 serum level in 361 type 2 diabetic patients with internal carotid artery stenosis undergoing carotid endarterectomy and in 598 diabetic controls without carotid atherosclerosis.

Results

We found that FGF23 median serum levels was significantly higher in patients than in diabetic controls [67.7 (59.5–77.8) pg/mL and 43.89 (37.5–50.4), P < 0.001] and was significantly and independently associated with unstable plaque in patients with internal carotid artery stenosis [OR, 5,71 (95 % CI, 2.09–15.29].

Conclusions

We have found, for the first time, that FGF23 could be associated with unstable plaque in type 2 diabetic patients with internal carotid artery stenosis.

Development and pilot feasibility study of a health information technology tool to calculate mortality risk for patients with asymptomatic carotid stenosis: the Carotid Risk Assessment Tool (CARAT)

Background

Patients with no history of stroke but with stenosis of the carotid arteries can reduce the risk of future stroke with surgery or stenting. At present, a physicians’ ability to recommend optimal treatments based on an individual’s risk profile requires estimating the likelihood that a patient will have a poor peri-operative outcomes and the likelihood that the patient will survive long enough to gain benefit from the procedure. We describe the development of the CArotid Risk Assessment Tool (CARAT) into a 2-year mortality risk calculator within the electronic medical record, integrating the tool into the clinical workflow, training the clinical team to use the tool, and assessing the feasibility and acceptability of the tool in one clinic setting.

Methods

We modified an existing clinical flowsheet with the local electronic medical record for the CARAT risk model. To understand how CARAT would fit into the existing clinical workflow, we observed the clinic and talked with the clinical staff to develop a process map for the existing clinical workflow. CARAT was completed by the clinic nurse for patients identified on the clinic schedule as having carotid narrowing. We analyzed post-implementation assessment in two ways: quantifying the proportion of eligible patients with whom CARAT was utilized, and surveying surgeons to understand the impact of CARAT on decision-making and clinical workflow.

Results

With minimum investment of institutional resources, we were able to produce a workable tool and pilot the tool in our clinic within a 6 month time period. Over 4 months, 287 patients were seen in the clinic with carotid narrowing, and clinic staff completed CARAT for 195 (68%). Per-surgeon completion rates ranged from 29 to 81%. Most patients (191 of 195, 98%) patients had a low 2-year calculated mortality risk. Most surgeons believed the risk assessment aligned with their expectations of patient predicted risk.

Conclusions

We successfully integrated CARAT into the existing electronic medical record and have preliminary evidence that CARAT can be a valuable tool for evaluating mortality risk for patients with diseased carotid arteries. Accuracy of the risk calculations must be evaluated in larger, multi-center studies.

Pathophysiology of Acute Cerebrovascular Syndrome in Patients With Carotid Artery Stenosis

BACKGROUND:

The mechanisms underlying acute cerebrovascular syndrome in patients with carotid artery stenosis remain unclear.

OBJECTIVE:

To assess the relationships among infarct localization, hemodynamics, and plaque components.

METHODS:

This prospective study included 38 patients with acute cerebrovascular syndrome resulting from ipsilateral carotid artery stenosis. Cerebral infarct localization was categorized into 3 patterns (cortical, border zone, and mixed pattern). Carotid plaque components were evaluated with T1-weighted magnetic resonance imaging and time-of-flight imaging. Cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) were also quantified.

RESULTS:

Infarcts were identified in 38 patients with the use of diffusion-weighted magnetic resonance imaging. On the basis of the assessment of hemodynamics, the cortical pattern was seen in 18 of 21 patients with type 1 ischemia (normal CBF, normal CVR), whereas the mixed pattern was seen in 2 patients with type 2 ischemia (normal CBF, impaired CVR) and 12 of 15 patients with type 3 ischemia (impaired CBF, impaired CVR). The plaque components were categorized into fibrous (4 patients), lipid-rich (14 patients), and intraplaque hemorrhage (IPH; 20 patients). Of the patients with fibrous plaque, 2 had border-zone and 2 had mixed-pattern infarcts. Of the patients with lipid-rich plaque, 7 had cortical and 6 had mixed-pattern infarcts. Of patients with intraplaque hemorrhage, 11 had cortical and 9 had mixed-pattern infarcts.

CONCLUSION:

Cortical infarction occurs as a result of vulnerable plaque. Reduced cerebral perfusion induces border-zone infarction. Both factors are implicated in mixed-pattern infarction. Developments in noninvasive diagnostic modalities allow us to explore the mechanisms behind acute cerebrovascular syndrome in carotid artery stenosis and to determine the ideal therapies.

Carotid Endarterectomy: A Review

Background:

Since the validation of carotid endarterectomy (CEA) as an effective means of stroke prevention, there has been renewed interest in its best indications and methods, as well as in how it compares to carotid angioplasty and stenting (CAS). This review examines these topics, as well as the investigation of carotid stenosis and the role of auditing and reporting CEAresults.

Investigation:

Brain imaging with CTor MRI should be obtained in patients considered for CEA, in order to document infarction and rule out mass lesions. Carotid investigation begins with ultrasound and, if results agree with subsequent, good-quality MRAor CTangiography, treatment can be planned and catheter angiography avoided. An equally acceptable approach is to proceed directly from ultrasound to catheter angiography, which is still the gold-standard in carotid artery assessment.

Indications:

Appropriate patients for CEA are those symptomatic with transient ischemic attacks or nondisabling stroke due to 70-99% carotid stenosis; the maximum allowable stroke and death rate being 6%. Uncertain candidates for CEA are those with 50 - 69% symptomatic stenosis, and those with asymptomatic stenosis ≥ 60% but, if selected carefully on the basis of additional risk factors (related to both the carotid plaque and certain patient characteristics), some will benefit from surgery. Asymptomatic patients will only benefit if surgery can be provided with exceptionally low major complication rates (3% or less). Inappropriate patients are those with less than 50% symptomatic or 60% asymptomatic stenosis, and those with unstable medical or neurological conditions.

Techniques:

Carotid endarterectomy can be performed with either regional or general anaesthesia and, for the latter, there are a number of monitoring techniques available to assess cerebral perfusion during carotid cross-clamping. While monitoring cannot be considered mandatory and no single monitoring technique has emerged as being clearly superior, EEG is most commonly used. “Eversion” endarterectomy is a variation in surgical technique, and there is some evidence that more widely practiced patch closure may reduce the acute risk of operative stroke and the longer-term risk of recurrent stenosis.

Carotid angioplasty and stenting:

Experience with this endovascular and less invasive procedure grows, and its technology continues to evolve. Some experienced therapists have reported excellent results in case series and a number of randomized trials are now underway comparing CAS to CEA. However, at this time it is premature to incorporate CAS into routine practice replacing CEA.

Auditing:

It has been shown that auditing of CEA indications and results with regular feed-back to the operating surgeons can significantly improve the performance of this operation. Carotid endarterectomy auditing is recommended on both local and regional levels.

Identification of a potential proinflammatory genetic profile influencing carotid plaque vulnerability

OBJECTIVE

Atherosclerosis and vascular remodeling after injury are driven by inflammation and mononuclear cell infiltration. Unstable atherosclerotic plaques are characterized by a large necrotic core. In this study we investigated the distribution and interaction between gene polymorphisms encoding proinflammatory molecules in an Italian population with internal carotid artery stenosis (ICAS). We also evaluated whether reciprocal interaction between these gene polymorphisms increased the risk of plaque vulnerability.

METHODS

In this genetic association study, 11 proinflammatory gene polymorphisms were analyzed in 933 individuals comprising 344 patients with ICAS who underwent carotid endarterectomy and 589 controls without ultrasound evidence of atherosclerosis or intimal thickening.

RESULTS

We found that interleukin (IL) 6 (IL-6), IL-1β, monocyte chemoattractant protein-1 (CCL2) macrophage inflammatory protein-1α (CCL3), E-selectin (SELE), intercellular adhesion molecule 1 (ICAM1), and matrix metalloproteinase-3 (MMP-3), and 9 (MMP-9) gene variants were independently and significantly associated with ICAS. The association remained significant even after the Bonferroni correction. We also found a genetic profile associated with different risks for ICAS, depending on the number of high-risk genotypes simultaneously present in an individual. Furthermore, proinflammatory genetic profiles are significantly more common in individuals with unstable carotid plaque.

CONCLUSIONS

Our study shows, for the first time, a reciprocal interaction between proinflammatory genotypes for the development and progression of ICAS.

Recanalization of extracranial internal carotid artery occlusion: A 12-year retrospective study

This study aimed to summarize therapy experience of carotid endarterectomy, carotid endarterectomy combined with Fogarty catheter embolectomy, and hybrid surgery for the treatment of extracranial internal carotid artery occlusion. The study included 65 patients with extracranial internal carotid artery occlusion who underwent carotid endarterectomy, carotid endarterectomy combined with Fogarty catheter embolectomy, or hybrid surgery in the Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, China between January 2006 and December 2012. Prior to surgery, all patients underwent perfusion CT or xenon CT to evaluate the occlusion. The procedure for each patient was chosen according to digital subtraction angiography data. The carotid artery was successfully recanalized in 46 of 51 patients who underwent carotid endarterectomy, 9 of 10 patients who underwent carotid endarterectomy combined with Fogarty catheter embolectomy, and 3 of 4 patients who underwent hybrid surgery. In patients with symptomatic carotid artery occlusion, the carotid artery can be recanalized by choosing a treatment procedure based on imaging examination findings.

Carotid endarterectomy and carotid artery stenting: changing paradigm during 10 years in a high-volume centre

BACKGROUND

We analysed the results of internal carotid artery (ICA) stenosis treatment at our institution over the last 10 years according to treatment modalities (carotid endarterectomy [CEA] vs carotid artery stenting [CAS]). Furthermore, we compared our results of treatment prior to the EVA-3S study being implemented into our practice (2003-2007) and after that (2008-2012).

METHOD

During the years 2003-2012, a total of 1,471 procedures were performed for ICA stenosis. CEA was done in 815 cases and CAS in 656 cases. The primary outcome was disabling stroke (mRS > 2) or myocardial infarction (MI) within 30 days after treatment. Secondary outcomes were frequency of transient ischaemic attacks (TIAs), minor strokes (stroke without impaired activities of daily living [ADL]) and any other significant complication. Comparisons of the results before and after 2008 were performed.

RESULTS

Major mortality and morbidity were divided according to treatment groups; reached 1.0 % in the CEA group and 3.0 % in the CAS group, p = 0.004. Minor stroke was recorded at 1.8 % and 2.7 % in the CEA and CAS, p = 0.245. TIAs in 1.0 % (CEA) and 4.7 % (CAS), p < 0.001. Any complication in 11.9 % (CEA) and 13.3 % (CAS), p = 0.401. In the overall results (i.e. CEA and CAS together), we found in 2008-2012 a decrease of incidence of TIAs (from 30/840 to 9/631, p = 0.011) and any complications (from 120/840 to 64/631, p = 0.017).

CONCLUSIONS

CEA performed in a high-volume centre is a safe procedure in properly indicated patients. In all subgroup analyses, CEA fared better than or at least of equal benefit as CAS. Since 2008, the frequency of TIAs and other complications decreased significantly. This study supports an idea of CEA being the first choice of treatment and CAS being reserved for strictly selected cases, such as re-stenosis after a previous carotid procedure, carotid dissection, ICA stenosis after radiotherapy, previous major neck surgery, contralateral cranial nerve palsy or tandem stenosis.

Factors influencing the decline in stroke mortality: a statement from the American Heart Association/American Stroke Association

BACKGROUND AND PURPOSE

Stroke mortality has been declining since the early 20th century. The reasons for this are not completely understood, although the decline is welcome. As a result of recent striking and more accelerated decreases in stroke mortality, stroke has fallen from the third to the fourth leading cause of death in the United States. This has prompted a detailed assessment of the factors associated with the change in stroke risk and mortality. This statement considers the evidence for factors that have contributed to the decline and how they can be used in the design of future interventions for this major public health burden.

METHODS

Writing group members were nominated by the committee chair and co-chair on the basis of their previous work in relevant topic areas and were approved by the American Heart Association Stroke Council's Scientific Statements Oversight Committee and the American Heart Association Manuscript Oversight Committee. The writers used systematic literature reviews, references to published clinical and epidemiological studies, morbidity and mortality reports, clinical and public health guidelines, authoritative statements, personal files, and expert opinion to summarize evidence and to indicate gaps in current knowledge. All members of the writing group had the opportunity to comment on this document and approved the final version. The document underwent extensive American Heart Association internal peer review, Stroke Council leadership review, and Scientific Statements Oversight Committee review before consideration and approval by the American Heart Association Science Advisory and Coordinating Committee.

RESULTS

The decline in stroke mortality over the past decades represents a major improvement in population health and is observed for both sexes and for all racial/ethnic and age groups. In addition to the overall impact on fewer lives lost to stroke, the major decline in stroke mortality seen among people <65 years of age represents a reduction in years of potential life lost. The decline in mortality results from reduced incidence of stroke and lower case-fatality rates. These significant improvements in stroke outcomes are concurrent with cardiovascular risk factor control interventions. Although it is difficult to calculate specific attributable risk estimates, efforts in hypertension control initiated in the 1970s appear to have had the most substantial influence on the accelerated decline in stroke mortality. Although implemented later, diabetes mellitus and dyslipidemia control and smoking cessation programs, particularly in combination with treatment of hypertension, also appear to have contributed to the decline in stroke mortality. The potential effects of telemedicine and stroke systems of care appear to be strong but have not been in place long enough to indicate their influence on the decline. Other factors had probable effects, but additional studies are needed to determine their contributions.

CONCLUSIONS

The decline in stroke mortality is real and represents a major public health and clinical medicine success story. The repositioning of stroke from third to fourth leading cause of death is the result of true mortality decline and not an increase in mortality from chronic lung disease, which is now the third leading cause of death in the United States. There is strong evidence that the decline can be attributed to a combination of interventions and programs based on scientific findings and implemented with the purpose of reducing stroke risks, the most likely being improved control of hypertension. Thus, research studies and the application of their findings in developing intervention programs have improved the health of the population. The continued application of aggressive evidence-based public health programs and clinical interventions is expected to result in further declines in stroke mortality.

Carotid endarterectomy without shunt: the role of cerebral metabolic protection

BACKGROUND

The optimal method to protect the brain from hemodynamic ischemia during carotid endarterectomy (CEA) remains controversial. This study reports our experience with induced arterial hypertension and selective etomidate cerebral protection in a cohort of patients who underwent CEA without shunting and continuous electroencephalography (EEG) monitoring.

METHODS

We reviewed retrospectively 102 consecutive CEAs performed in 102 patients with routine EEG monitoring and general anesthesia between March 1998 and October 2002. There were 65 (66%) symptomatic and 37 (34%) asymptomatic individuals. A protocol of induced arterial hypertension against EEG ischemic changes during carotid artery cross clamping was followed. Only patients with EEG changes refractory to induced hypertension went into etomidate-induced burst suppression.

RESULTS

EEG changes were classified as mild, moderate and severe. Twenty patients (19.6%) developed asymmetric EEG changes, of which the great majority were mild and moderate (75%, p< 0.05). Seven patients with moderate (n=3) and severe (n=4) EEG changes needed etomidate cerebral protection. There were no mortalities and only one stroke (0.98%) is reported in the series. The morbidity rate was 6.8% and included transient cranial nerve palsies (n=5) and wound hematoma (n=1).

CONCLUSIONS

Carotid endarterectomy can be safely performed with EEG monitoring and selective induced arterial hypertension and etomidate cerebral protection. Our results suggest that this method may be a good alternative for shunting and its inherent risks.

Simultaneous noncontrast angiography and intraplaque hemorrhage (SNAP) imaging for carotid atherosclerotic disease evaluation

A simultaneous noncontrast angiography and intraplaque hemorrhage (SNAP) MR imaging technique is proposed to detect both luminal stenosis and hemorrhage in atherosclerosis patients in a single scan. Thirteen patients with diagnosed carotid atherosclerotic plaque were admitted after informed consent. All scans were performed on a 3T MR imaging system with SNAP, 2D time-of-flight and magnetization-prepared 3D rapid acquisition gradient echo sequences. The SNAP sequence utilized a phase sensitive acquisition, and was designed to provide positive signals corresponding to intraplaque hemorrhage and negative signals corresponding to lumen. SNAP images were compared to time-of-flight images to evaluate lumen size measurements using linear mixed models and the intraclass correlation coefficient. Intraplaque hemorrhage identification accuracy was evaluated by comparing to magnetization-prepared 3D rapid acquisition gradient echo images using Cohen's Kappa. Diagnostic quality SNAP images were generated from all subjects. Quantitatively, the lumen size measurements by SNAP were strongly correlated (intraclass correlation coefficient = 0.96, P < 0.001) with those measured by time-of-flight. For intraplaque hemorrhage detection, strong agreement (κ = 0.82, P < 0.001) was also identified between SNAP and magnetization-prepared 3D rapid acquisition gradient echo images. In conclusion, a SNAP imaging technique was proposed and shows great promise for imaging both lumen size and carotid intraplaque hemorrhage with a single scan.

Unprotected carotid artery stenting in symptomatic patients with high-grade stenosis: results and long-term follow-up in a single-center experience

BACKGROUND AND PURPOSE

The use of cerebral protection during CAS is an extended practice. Paradoxically it is open to question because it can lead to potential embolic complications. The aim of this study was to evaluate the safety and efficacy of CASWPD in patients with severe symptomatic carotid artery stenosis.

MATERIALS AND METHODS

A prospective study was performed including 210 consecutive patients (201 symptomatic and 9 asymptomatic) with carotid artery stenosis >70%. All patients were treated by CASWPD. Angiographic results and neurologic complications were recorded during the procedure and within 30 days after it. All patients underwent clinical evaluation and Doppler sonography follow-up at 3, 6, and 12 months after the procedure.

RESULTS

Two hundred twenty carotid arteries were treated. The average degree of stenosis was 88.9%. The procedure was successfully completed in 212 (96.4%) arteries. After stent placement, 98.6% of arteries showed no residual stenosis or <30%. Balloon angioplasty dilation before stent placement was performed in 16% of cases. During the 30-day periprocedural period, there were 3 major complications (1.4%), including 1 disabling ischemic stroke, 1 acute stent thrombosis, and 1 MI. The last 2 patients died from these complications. At 1-year follow-up 24 (12.8%) restenoses, 2 new ipsilateral strokes, 1 contralateral stroke, and 5 deaths (2.7%) had occurred. None of these deaths were related to the initial stroke.

CONCLUSIONS

In our study, unprotected stent placement in symptomatic patients with severe carotid artery stenosis has demonstrated a low incidence of complications. We believe that this is due to the reduction of maneuvering and manipulation through the stenosis and to the protective effect of the stent placement before angioplasty balloon dilation.

Carotid artery stenting for primary and secondary stroke prevention

BACKGROUND

Carotid artery disease is a major cause of the disability and mortality associated with strokes. Ischemic stroke remains the major cause of adult disability and third-leading cause of adult mortality, and carotid revascularization currently remains the principal surgical tool in the prophylaxis of this disease.

METHODS

The literature representing the current body of evidence for carotid revascularization and the authors' current practices in the management of this disease are summarized in this review.

RESULTS

We provide an evidence-based narration of the development and current status of carotid artery stenting (CAS) by reviewing 1) the evidence for carotid revascularization from early carotid endarterectomy (CEA) trials; 2) the randomized trials comparing CEA and CAS, with a special emphasis on the recently published results of the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST), which have been a "game-changer," tipping the balance towards accepting CAS as a safe, equally effective, and durable alternative to CEA for all patients requiring carotid revascularization; and 3) the technical advances in CAS after enrollment of patients in the CREST.

CONCLUSIONS

CAS and CEA are complementary procedures. Judicious selection of the procedure is made on a case-by-case basis.

Near-infrared indocyanine green videoangiography for assessment of carotid endarterectomy

BACKGROUND

Intraoperative fluorescence angiography with indocyanine green (ICG) as a tracer has recently been introduced as a novel technique for neurosurgery. We evaluated the feasibility and efficacy of near-infrared (NIR) indocyanine green (ICG) videoangiography for patients undergoing carotid endarterectomy (CEA).

METHODS

Sixty patients (7 females, 53 males; mean age, 71.8 years) undergoing CEA for severe stenosis of the internal carotid artery (ICA) were included. During CEA, microscope-integrated intraoperative NIR videoangiographic recording was performed before and after the excision of the plaque and closure of the ICA.

RESULTS

During the 60 CEA procedures, 60 consecutive ICG videoangiographic examinations were performed. All patients tolerated the intravenous injection of ICG well with no adverse effects. The videoangiographic study showed the blood stream of the ICA in all cases and the position of plaque in some cases.

CONCLUSION

Microscope-based ICG videoangiography is simple, and provides reliable and rapid intraoperative assessment of CEA.