Changes in retinal vascular density measured by optical coherence tomography angiography in patients with carotid artery stenosis after carotid artery stenting and angioplasty

PURPOSE

The aim of this study was to compare the effect of carotid artery stenting and angioplasty (CASA) on retinal vascular density (VD) in patients with severe carotid stenosis with a healthy control group and to evaluate using optical coherence tomography angiography (OCTA).

METHODS

For this prospective study, eyes on the operated side constituted the ipsilateral eye group, and the other eye constituted the contralateral eye group. 40 eyes of 40 patients with ipsilateral eye of carotisid artery stenosis (CAS), 34 eyes on contralateral side, and 30 healthy eyes (control group) were included in this study. We performed quantitative OCTA analyses of retinal VD changes, before and after CASA. The main outcome measures were the quantitative changes of VD of superficial capillary plexus (SCP) and deep capillary plexus (DCP).

RESULTS

We evaluated the VD of ipsilateral eyes and contralateral eyes separately before and after the procedure. All patients did not have visual symptoms. There was no significant difference in the VD of SCP in all groups before the procedure. No significant change was observed in all groups when the VD of the SCP was compared before and after the procedure. The VD of the DCP in the ipsilateral and contralateral group improved significantly after CASA.

CONCLUSION

OCTA could noninvasively detect retinal VD improvements after CASA in CAS patients. Quantitative changes in VD evaluated using OCTA are thought to be early indicators in the diagnosis of CAS and in the follow-up of treatment success.

Purtscher-like retinopathy following carotid angioplasty and stenting in the treatment of severe carotid stenosis

We present a case of Purtscher-like retinopathy (PLR) following carotid angioplasty and stenting (CAS). A 56-year-old man with a history of severe stenosis of the left carotid artery and treated by CAS refers acute and painless visual loss on the left eye (OS) 48 h after the procedure. Funduscopic examination showed cotton wool spots and intraretinal hemorrhages confined to the peripapillary and posterior pole of the OS. The optical coherence tomography (OCT) showed retinal thickening and hyperintense lesions in the inner nuclear layer retina.

Internal Carotid Artery Stenosis and Ipsilateral Subretinal Drusenoid Deposits

Purpose

Subretinal drusenoid deposits (SDDs) in age-related macular degeneration (AMD) are strongly associated with vasculopathies such as myocardial infarction and ischemic stroke. This study evaluates ischemic stroke subjects for SDDs to determine whether ocular hypoperfusion from internal carotid artery (ICA) stenosis is associated with ipsilateral SDDs.

Methods

A cross-sectional study at Mount Sinai Hospital recruited 39 subjects with ischemic stroke (aged 52-90; 18 women, 21 men); 28 completed all study procedures. Computed tomography (CT) of the head and neck evaluated 54/56 ICAs for stenosis criteria: none (n = 33), mild (n = 12), moderate (n = 3), severe (n = 3), and complete (n = 3). Spectral-domain optical coherence tomography (SD-OCT) scans were read to consensus by two masked graders for soft drusen, SDDs and choroidal thickness (CTh; choroidal thinning = CTh < 250 µm). Univariate testing was done with Fisher's exact test. Multivariate logistic regression models tested age, gender, and ICA stenosis as covariates.

Results

Moderate or more ICA stenosis (≥50%-69%) was significantly associated with ipsilateral choroidal thinning (P = 0.021) and ipsilateral SDDs (P = 0.005); the latter were present distal to six of nine stenosed ICAs versus five of 33 normal ICAs. Mild ICA stenosis (≥1%-49%) was not significantly associated with ipsilateral SDDs. Multivariate regression found that older age (P = 0.015) and moderate or more ICA stenosis (P = 0.011) remained significant independent risks for ipsilateral SDDs.

Conclusions

At least moderate ICA stenosis (≥50%-69%) is strongly associated with ipsilateral SDDs and choroidal thinning, supporting downstream ophthalmic artery and choroidal hypoperfusion from ICA stenosis as the mechanism for SDD formation. SDDs may thus serve as sensitive biomarkers for ischemic stroke and other vascular diseases.

Hospital and long-term results of carotid endarterectomy in patients with different severity of coronary artery lesion according to syntax score

AIM

Analysis of in-hospital and long-term results of carotid endarterectomy (CEE) in patients with different severity of coronary atherosclerosis.

MATERIAL AND METHODS

This comparative, retrospective, open study for the period from January 2013 to April 2020 included 1719 patients operated on for occlusive-stenotic lesions of the internal carotid arteries (ICA). Classical and eversion CEA were used as revascularization strategies. The criteria for inclusion in the study were: 1. Presence of coronary angiography within six months before the present CEE; 2. A history of myocardial revascularization in patients with severe coronary lesions. Depending on the severity of coronary atherosclerosis, all patients were divided into 3 groups: Group 1-871 (50.7 %) patients - with the presence of hemodynamically significant stenosis of the coronary arteries (CA) with a history of myocardial revascularization; Group 2-496 (28.8 %) patients - with the presence of hemodynamically insignificant lesions of the coronary artery (up to 70 %, not inclusive, and the trunk of the left coronary artery, up to 50 %, not inclusive); Group 3-352 (20.5 %) patients - without signs of atherosclerotic lesions of the coronary artery. In group 1, the observation period was 56.8±23.2 months, in group 2-62.0±15.6 months, in group 3-58.1±20.4 months.

RESULTS

During the hospital observation period, there were no significant intergroup differences in the number of complications. All cardiovascular events were detected in isolated cases. The most common injury was damage to the cranial nerves, diagnosed in every fifth patient in the total sample. The combined endpoint (CET), including death + myocardial infarction (MI) + acute cerebrovascular accident/transient ischemic attack (stroke/TIA), was 0.75 % (n=13). In the long-term follow-up period, when comparing survival curves, group 3 revealed the largest number of ischemic strokes (p = 0.007), myocardial infarction (p = 0.03), and CCT (p = 0.005). There were no intergroup differences in the number of deaths (p=0.62).

CONCLUSION

The results of the study showed that there was no significant intergroup difference in the development of complications at the hospital postoperative stage. However, in the long-term follow-up period, a group of patients with isolated lesions of the ICA demonstrated a rapid increase in the number of MI, stroke/TIA, and a combined endpoint, which was apparently associated with low compliance and progression of atherosclerosis in previously unaffected arteries.

An international, multispecialty, expert-based Delphi Consensus document on controversial issues in the management of patients with asymptomatic and symptomatic carotid stenosis

OBJECTIVE

Despite the publication of various national/international guidelines, several questions concerning the management of patients with asymptomatic (AsxCS) and symptomatic (SxCS) carotid stenosis remain unanswered. The aim of this international, multi-specialty, expert-based Delphi Consensus document was to address these issues to help clinicians make decisions when guidelines are unclear.

METHODS

Fourteen controversial topics were identified. A three-round Delphi Consensus process was performed including 61 experts. The aim of Round 1 was to investigate the differing views and opinions regarding these unresolved topics. In Round 2, clarifications were asked from each participant. In Round 3, the questionnaire was resent to all participants for their final vote. Consensus was reached when ≥75% of experts agreed on a specific response.

RESULTS

Most experts agreed that: (1) the current periprocedural/in-hospital stroke/death thresholds for performing a carotid intervention should be lowered from 6% to 4% in patients with SxCS and from 3% to 2% in patients with AsxCS; (2) the time threshold for a patient being considered "recently symptomatic" should be reduced from the current definition of "6 months" to 3 months or less; (3) 80% to 99% AsxCS carries a higher risk of stroke compared with 60% to 79% AsxCS; (4) factors beyond the grade of stenosis and symptoms should be added to the indications for revascularization in AsxCS patients (eg, plaque features of vulnerability and silent infarctions on brain computed tomography scans); and (5) shunting should be used selectively, rather than always or never. Consensus could not be reached on the remaining topics due to conflicting, inadequate, or controversial evidence.

CONCLUSIONS

The present international, multi-specialty expert-based Delphi Consensus document attempted to provide responses to several unanswered/unresolved issues. However, consensus could not be achieved on some topics, highlighting areas requiring future research.

Comparison of pre-mortem 2D-3D ultrasound examination to post-mortem micro-CT of carotid arteries - first experiences

Background and purpose

A prerequisite for the treatment of carotid atherosclerosis is the accurate measurement of the stenosis, that is most commonly evaluated by duplex ultrasonography. In this study, we aimed to verify the reliability of 2D and 3D ultrasonography, comparing the data to results of post-mortem micro-CT examination.

.

Methods

Neurological patients with any life-threatening, presumably fatal neurological disease were enrolled. Ultrasound examinations were performed with a Philips Epiq 5G machine, using a VL13-5 broadband linear volume array transducer. Plaque length, diameter and vessel area reduction (stenosis) were calculated using the 2D images. Finally, the stenosis was reassessed using automatized, 3D application as well. After the death of the patient, autopsy was performed, during which the previously examined carotid artery was removed. The samples were examined with micro-CT. Similar to the ultrasound examination, plaque length, diameter and vessel area reduction (stenosis) were determined.

.

Results

Ten vessels of seven patients were eligible for complex comparison. Plaque diameter and length measured by CT did not correlate with the ultrasound data. CT-measured axial plaque and vessel areas showed no correlation with ultrasound results either. While determining the strength of correlation between stenoses measured by the different modalities, significant correlation was found between the results measured by ultrasound (2D) and CT (Pearson r: 0.902, P<0.001).

.

Conclusion

Three-dimensional ultrasound analysis is a spectacular method for examining carotid plaques, as it can assist in a more detailed evaluation of the plaque morphology and composition, thereby identifying plaques with a particularly high risk of stroke. Micro-CT is an excellent tool for the exact determination of calcified plaque areas, but ultrasound images are not suitable yet for such a precise examination due to acoustic shadowing and artifacts.

.

A Multicentric Study of Different Methods of Open Surgical Cerebral Revascularization for Internal Carotid Artery Orifice Stenosis

To analyze the long-term results of transposition of the internal carotid artery (ICA) into the lateral wall of the external carotid artery (ECA) in the presence of hemodynamically significant stenosis of the ICA. During the period from 3.10.2017 to 28.12.2020, 784 patients with isolated hemodynamically significant ICA orifice stenosis were included in the present retrospective multicentric open comparative study "Russian Birch." Depending on the implemented surgical technique, groups were formed: group 1 (n = 517) - eversion carotid endarterectomy (eCEA); group 2 (n = 193) classic CEA with implantation of a xenopericardium patch treated with di-epoxy compounds; group 3 (n = 74) - transposition of the ICA into the lateral wall of the ECA. Transposition of the ICA into the lateral wall of the ECA is performed as follows. The common carotid artery, ECA, and ICA are isolated and then they are clamped with vascular clamps. At the same time, the ICA and ECA are clamped 4 cm above the orifice. The ICA is cut 2.5 cm above the orifice. Then the section of the ICA with local stenosis in the orifice is sutured with a polypropylene suture. At the same time, the redundant nonfunctioning ICA stump is not resected due to the fact that there are receptors of the carotid sinus at the ICA orifice. Thus, such manipulation may damage the sinus, causing arterial hypertension that is difficult to control in the postoperative period. Then, in the lateral wall of the ECA 2.5 cm above the orifice, a 0.5 cm diameter round hole is formed using a scalpel and angled vascular scissors. Then an end-to-side anastomosis between the severed section of the ICA and the rounded opening formed in the lateral wall of the ECA is performed using a polypropylene suture. Vascular clamps are removed and blood flow is started. No complications were detected in the hospital postoperative period. No adverse cardiovascular events were registered in group 3 in the long-term follow-up period. The group of classic CEA with implantation of a xenopericardium patch treated with di-epoxy compounds showed the highest number of fatal outcomes from acute cerebrovascular accident (CVA) (Group 1: 0.2%, n = 1; group 2: 2.6%; n = 5; p = 0.008); nonfatal ischemic CVA (group 1: 0.6%, n = 3; group 2: 14.0%, n = 27; p < 0.0001); ICA restenosis (more than 60%) requiring a repeat revascularization (group 1: 0.8%, n = 4; group 2: 16.6%, n = 32; p < 0.0001). The cause of all CVAs after classical CEA was restenosis of the ICA due to neointimal hyperplasia; after eversion CEA and progression of atherosclerosis. The composite end point was statistically more frequent after classical CEE with plasty of the reconstruction area with a diepoxy-treated xenopericardium patch (group 1: 1.0%, n = 5; group 2: 17.7%, n = 33; p < 0.0001). When analyzing the survival curves free of ICA restenosis, it was determined that the overwhelming number of all ICA restenosis requiring revascularization in the group of classical CEA with implantation of a diepoxy-treated xenopericardium patch is diagnosed as early as 6 months after surgery. In the group of eversion CEA, the loss of the vessel lumen is most often visualized more than a year after the intervention. When comparing the survival curves (Logrank test), it was determined that restenosis of the ICA develops statistically more frequently (p < 0.0001) after classical CEA with implantation of a diepoxytreated xenopericardium patch. Transposition of the ICA into the lateral wall of the ECA is not accompanied by the risk of ICA restenosis due to the absence of inflammation of the internal artery wall after endarterectomy. Thus, this technique can be an alternative to CEA and be routinely used in case of local hemodynamically significant stenosis of the ICA orifice. Classical CEA with patch implantation is the least preferable operation due to the high risk of ICA restenosis in the mid-term and long-term follow-up.

Effect of Treatment Choice on Short-Term and Long-Term Outcomes for Carotid Near-Occlusion: A Meta-Analysis

OBJECTIVE

Current guidelines recommend best medical treatment (BMT) over revascularization for carotid near-occlusion (CNO); however, it remains unclear whether BMT, carotid artery stenting (CAS), or carotid endarterectomy (CEA) is the optimal treatment strategy. The present meta-analysis aimed to compare outcomes among patients with CNO receiving BMT, CAS, or CEA.

METHODS

PubMed, Web of Science, Scopus, and Embase were searched. English studies with ≥1 month follow-up, that used established CNO diagnostic guidelines, that provided outcomes by treatment, and in which 95% confidence intervals (CIs) were calculable were included. Studies on acute ischemic stroke (AIS) requiring emergent reperfusion therapy, nonatherosclerotic lesions, nonprimary research articles, non-English, and nonhuman studies were excluded. Outcomes were mortality, AIS, transient ischemic attack, myocardial infarction within and beyond 30 days, and restenosis. A generalized linear mixed model, subgroup analysis, and meta-regression were used to compare outcomes.

RESULTS

Thirty-eight studies were included. Pooled rates for AIS beyond 30 days were 9.90% (95% CI, 4.31%-21.16%), 0.79% (95% CI, 0.24%-2.53%), and 0.80% (95% CI, 0.15%-4.07%) for BMT, CAS, and CEA, respectively. Subgroup analysis was statistically significant (P < 0.001). Meta-regression showed lower incidence favoring procedural intervention (CAS vs. BMT, P = 0.001; CEA vs. BMT, P = 0.003). Subgroup analysis for mortality beyond 30 days was also significant (P = 0.016) but meta-regression did not favor one treatment over another. Other outcomes were not statistically significant.

CONCLUSIONS

Revascularization for CNO may decrease long-term stroke rates. Given that current guidelines are based on randomized controlled trials from the 1990s, updated randomized trials are warranted to determine the optimal treatment for CNO.

Influence of Carotid Endarterectomy on Choroidal Perfusion: The INFLATE Study

PURPOSE

Patients with clinically significant carotid artery stenosis (CAS) undergoing carotid artery endarterectomy (CEA) were imaged with swept-source OCT angiography (SS-OCTA) imaging protocol to determine if there were changes in choroidal blood flow after surgery.

DESIGN

Prospective observational study.

PARTICIPANTS

Patients with clinically significant CAS undergoing unilateral CEA.

METHODS

All participants underwent SS-OCTA imaging using a 6 × 6-mm scan pattern on both eyes before CEA and within 1 week after CEA. Previously validated automated algorithms were used to measure the mean choroidal thickness (MCT) and choroidal vascular index (CVI) within 2.5-mm and 5-mm circles centered on the fovea. Multivariable regression analysis was conducted to evaluate the impact of various baseline factors including age, mean arterial blood pressure, and degree of stenosis, on both baseline of MCT and CVI, and the changes in MCT and CVI.

MAIN OUTCOME MEASURES

Changes in MCT and CVI.

RESULTS

One hundred sixteen eyes from 60 patients with a mean age of 71.57 ± 7.37 years were involved in the study. At baseline, MCT in both the 2.5-mm and 5-mm circles was significantly thinner on the surgical side compared with the nonsurgical side (P = 0.03), while no significant differences were seen in the CVI at baseline between the 2 sides (2.5-mm circle: P = 0.24; 5-mm circle: P = 0.09). Within 1 week after CEA, there were significant increases in the MCT on the surgical side, as compared with the nonsurgical side, in both the 2.5-mm (P < 0.001) and the 5-mm (P < 0.001) circles. No significant change in mean CVI was noted before and after CEA on the surgical side versus the nonsurgical side (2.5-mm circle: P = 0.30; 5-mm circle: P = 0.97). Multivariable regression analysis revealed that baseline MCT before CEA significantly decreased with age on both the surgical (P < 0.001) and nonsurgical sides (P = 0.003) while the changes in MCT and CVI after CEA were not associated with age, mean arterial blood pressure, or degree of stenosis.

CONCLUSION

A rapid and significant increase in MCT was observed on the ipsilateral side of CEA, suggesting an improvement in choroidal perfusion within 1 week after surgery.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

[Evolution of surgical approaches to carotid bifurcation]

Carotid endarterectomy is preferable for prevention of acute cerebrovascular accident associated with atherosclerotic lesions of internal carotid artery. Modern interest in minimizing local complications and small excisions is also actual in carotid surgery. The authors review the modern literature data on evolution of carotid arteries exposure. Cutaneous mini-incision, transverse skin incision and retrojugular approach are discussed. The authors consider the advantages and possible complications of each technique.

Quantitative Assessment of Retinal and Choroidal Microvasculature in Asymptomatic Patients with Carotid Artery Stenosis

SIGNIFICANCE

Carotid disease contributes to 15 to 20% of all ischemic strokes, one of the leading causes of permanent disabilities and mortality globally. With its growing prevalence and the inflicted disability rates, screening for anomalies that precede the onset of its serious complications is of crucial global significance.

PURPOSE

This study aimed to assess the relationship between retinal and choroidal perfusion changes with the degree of stenosis using quantitative swept-source optical coherence tomography angiography in patients with internal carotid artery stenosis.

METHODS

A retrospective cohort study was conducted in 72 eyes with carotid stenosis. According to the degree of stenosis, the participants were divided into a healthy group (group 1: 34 eyes), a mild-moderate stenosis group (group 2: 22 eyes), and a severe stenosis group (group 3: 16 eyes). Swept-source optical coherence tomography angiography was performed to scan macular fovea. Capillary density values in the different retinal and choroidal layers were the major measurements for our study.

RESULTS

Mean vessel density in the midchoroid layer was significantly higher in groups 2 and 3 compared with group 1. Deep choroid disclosed significantly superior vascular density values in group 3 compared with groups 2 and 1. Superficial and deep capillary plexus showed decreased vascular density values when comparing group 3 with groups 1 and 2, although they were not significant.

CONCLUSIONS

Our report provides the first evidence that choroidal microvascular changes were correlated with severity of carotid artery stenosis. Optical coherence tomography angiography can sensitively detect subtle, early changes in the ocular blood in carotid disease representing a useful, noninvasive, and objective approach to the retinal microvasculature.

Prognostic Significance of Carotid and Lower Extremity Artery Stenosis in Patients With High and Very High Cardiovascular Risk

Aim      To study prognostic significance of the degree of stenosis of carotid and lower-extremity arteries (LEA) in patients at high and very high risk of cardiovascular complications (CVC).Material and methods  The study included men and women aged 40-67 years at high and very high risk of CVC. Duplex ultrasound scanning of carotid arteries and LEA was performed for all patients. Laboratory tests included measurements of glucose, glycated hemoglobin, total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides, uric acid, creatinine with estimation of glomerular filtration rate (GFR) using the CKD-EPI Creatinine Equation formula, and high-sensitivity C-reactive protein (hsCRP). Composite endpoint was death from CVC, nonfatal myocardial infarction, nonfatal stroke, and coronary revascularization.Results The study included 214 patients from groups of high and very high risk of CVC. Median age of patients was 59.0 [53.2; 64.0] years. A very high risk was identified in 141 (65.8 %) patients and a high risk of CVC in 73 (34.1 %). Atherosclerotic plaques in at least one vascular bed were found in 191 (89.3 %) patients. Duration of the follow-up period was 32.0 [13.7; 49.1] months. Outcomes comprising the composite endpoint were observed in 36 (16.8 %) patients. Presence of carotid stenosis ≥35 % was not statistically significantly associated with the occurrence of outcomes comprising the composite endpoint (relative risk, RR: 1.22; 95 % confidence interval, CI: 0.56-2.66; p=0.607). In contrast, the presence of LEA stenosis ≥35 % was associated with a 2.51 times increased RR of CVC (95 % CI: 1.02-6.23; p=0.044).Conclusion      In patients from the groups of high risk and very high risk of CVC, the presence of LEA stenosis ≥35 % predicted the development of severe CVC with a 69.4% sensitivity and a 61.8% specificity. The presence of LEA stenosis ≥35 %, but not of carotid arteries, was an independent predictor of severe CVC (RR, 2.51; 95 % CI: 1.02-6.23; p=0.044) after adjustments for sex, age, presence of arterial hypertension, diabetes mellitus, ischemic heart disease, obesity, smoking, LDL-C, GFR, and drug therapy.

A Machine Learning Model for the prediction of the progression of carotid arterial stenoses

Atherosclerotic carotid plaque development results in a steady narrowing of the artery lumen, which may eventually trigger catastrophic plaque rupture leading to thromboembolism and stroke. The primary cause of ischemic stroke in the EU is carotid artery disease, which increases the demand for tools for risk stratification and patient management in carotid artery disease. Additionally, advancements in cardiovascular modeling over the past few years have made it possible to build accurate three-dimensional models of patient-specific primary carotid arteries. Computational models then incorporate the aforementioned 3D models to estimate either the development of atherosclerotic plaque or a number of flow-related parameters that are linked to risk assessment. This work presents an attempt to provide a carotid artery stenosis prognostic model, utilizing non-imaging and imaging data, as well as simulated hemodynamic data. The overall methodology was trained and tested on a dataset of 41 cases with 23 carotid arteries with stable stenosis and 18 carotids with increasing stenosis degree. The highest accuracy of 71% was achieved using a neural network classifier. The novel aspect of our work is the definition of the problem that is solved, as well as the amount of simulated data that are used as input for the prognostic model.Clinical Relevance-A prognostic model for the prediction of the trajectory of carotid artery atherosclerosis is proposed, which can support physicians in critical treatment decisions.

Protected carotid artery stenting in patients with severe stenosis

Intraplaque hemorrhage (IPH) and ulcers are the major findings of unstable plaques. In addition, initial symptoms are associated with postprocedural complications after carotid artery stenting (CAS). The aim of this study was to determine the safety of CAS using an embolic protection device in symptomatic patients with severe carotid artery stenosis and unstable plaques such as IPH and ulcers. This retrospective study included 140 consecutive patients with severe carotid stenosis. These patients underwent preprocedural carotid vessel wall imaging to evaluate the plaque status. We analyzed the incidence of initial clinical symptoms, such as headache, nausea, and vomiting, after CAS. The primary outcomes analyzed were the incidence of stroke, myocardial infarction, and death within 30 days of CAS. Sixty-seven patients (47.9%) had IPH, and 53 (38.9%) had ulcers on carotid wall imaging/angiography. Sixty-three patients (45.0%) had acute neurological symptoms with positive diffusion-weighted image findings. Intraluminal thrombi on initial angiography and flow arrest during CAS were significantly higher in patients with IPH and symptomatic patients. Symptoms were significantly higher in patients with IPH than in those without (63.5% vs 35.1%, P < .001). There were no significant differences in clinical symptoms after stenting or in primary outcomes, regardless of IPH, ulcer, or initial symptoms. IPH and plaque ulceration are risk factors in symptomatic carotid stenosis. However, IPH and plaque ulceration were not a significant risk factors for cerebral embolism during protected carotid artery stent placement in patients with carotid stenosis. Protected CAS might be feasible and safe despite the presence of unstable plaques.

Diagnostic and Prognostic Value Analysis of miR-206 in Asymptomatic Carotid Artery Stenosis

Introduction: To investigate the expression level of miR-206 in serum of patients with asymptomatic carotid artery stenosis (CAS) and estimate the value of miR-206 in the diagnosis and prognosis of asymptomatic CAS.

Methods: A total of 206 individuals enrolled in this study, including 105 CAS patients and 101 controls. RT-qPCR technology was applied to measure the relative level of miR-206, and Pearson’s correlation coefficient was performed to analyze the relationship between carotid artery stenosis degree and miR-206 level. An ROC curve was drawn to assess the diagnostic value of miR-206 in asymptomatic CAS. The 5-year prognosis of asymptomatic CAS patients was tested using multivariate Cox regression analysis and Kaplan-Meier survival curve.

Results: MiR-206 expression was reduced in asymptomatic CAS patients. The AUC of the ROC curve of miR-206 was 0.939, with a sensitivity of 86.70% and a specificity of 86.14%. The amount of CAS gradually increased with the decrease of miR-206 level. Seven-teen patients in the low miR-206 expression group developed CIEs, and 3 patients in the high miR-206 expression group developed CIEs during the 5-year follow-up. miR-206 and the amount of CAS were independent factors for the occurrence of CIEs within 5 years in asymptomatic CAS patients.

Conclusion: Serum miR-206 has high diagnostic accuracy for asymptomatic CAS and has predictive value for the incidence of CIEs in patients within 5 years.

[Evaluation of the level of carotid bifurcation and the morphology of extracranial internal carotid artery in patients with carotid stenosis by color doppler ultrasound and digital subtraction angiography]

Objective: To evaluate the value of color Doppler ultrasound and digital subtraction angiography (DSA) in evaluating the level of carotid bifurcation and the morphology of extracranial internal carotid artery in patients with atherosclerotic carotid stenosis. Methods: The carotid artery examination data of 186 patients with atherosclerotic carotid stenosis who underwent carotid DSA and color Doppler ultrasound in Shanghai Changzheng Hospital from July 2017 to June 2019 were retrospectively analyzed, including 154 males and 32 females, with ages ranging from 36 to 84 (66±8) years old. The correlation between the position of carotid bifurcation and the level of cervical spine, the distance from the position of carotid bifurcation to mandibular angle, the correlation of the level of bifurcation with the length of neck, and the incidence of carotid distortion were analyzed. Results: DSA showed that the most common position of carotid bifurcation was at C3 level on the left [37.3% (56/150)], and at C3-C4 level on the right [33.6% (42/125)], and the highest position was at C2 level on the left, and at C2-C3 levels on the right, while the lowest level on both sides was at C5 level. The incidence of high bifurcation of left carotid artery (C3 and above) was 46% (69/150), which was higher than that of right carotid artery [21.6% (27/125), P<0.001]. The incidence of high carotid bifurcation in men and women was 33.2% (76/229) and 43.5% (20/46), respectively, with no significant difference (P = 0.182). Carotid ultrasound showed that the distance between the left carotid bifurcation and the mandibular angle was (3.0±1.3) cm, which was shorter than that on the right [(3.4±1.2) cm] (P<0.001). The distance between carotid bifurcation and mandibular angle in men and women was (3.2±1.2) cm and (3.3±1.0) cm, respectively, with no significant difference (P = 0.093). There was no significant correlation between carotid bifurcation level and carotid length (right: r = 0.02, P = 0.091; left: r = 0.01, P = 0.927). The incidence of carotid artery distortion was 28.1% (9/32) in women and 15.6% (24/154) in men, with no significant difference (P = 0.091). The incidence of right carotid artery distortion in high bifurcation group was 59.3% (16/27), which was higher than that in non-high bifurcation group [3.1% (3/98)] (P<0.001). Likewise, the incidence of left carotid artery distortion in high bifurcation group was 30.4% (21/69), which was higher than that in non-high bifurcation group [2.5% (2/81)] (P<0.001). Conclusions: The bifurcation position of left carotid artery in patients with atherosclerotic carotid stenosis is higher than that of the right. Patients with high bifurcation of carotid artery are more likely to be complicated with carotid distortion. Preoperative color doppler ultrasound combined with DSA can evaluate the distortion of extracranial carotid artery, thereby providing reference for the selection of surgical methods.

Role of risk scoring systems in predicting life expectancy after carotid endarterectomy in asymptomatic patients

OBJECTIVE

The aim of this study is to compare and to test the performance of all available risk scoring systems (RSSs) designed to predict long-term survival rate in asymptomatic candidate patients for carotid endarterectomy (CEA) for significant carotid artery stenosis.

METHODS

Data on asymptomatic patients who underwent CEA in three high-volume centers were prospectively recorded. Through literature research using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations, six RSSs were identified for the intent of the study. Primary endpoints were 3- and 5-year survival rates after CEA. All items used as variables to compose multiple RSSs were applied to every patient in the study population. The 3- and 5-year mortality prediction rates for each score were assessed by sensitivity, specificity, and predictive negative and positive value calculation, as well as univariable Cox proportional hazard models with the Harrell C index.

RESULTS

During the study period, 825 CEAs in 825 asymptomatic patients were analyzed. All items used in RSSs were available in the dataset, with some concerns regarding their definition and application among RSSs. The 3- and 5-year survival rates of the study cohort were 94.5% and 90.3%, respectively. Among the six RSSs analyzed, no RSS demonstrated optimal results in terms of mortality rate prediction accuracy, although some scores had good diagnostic and risk of death precision.

CONCLUSIONS

RSSs, when used alone, fail to optimally detect postoperative life expectancy in asymptomatic CEA patient candidates. Further prospective controlled studies are needed to compose and validate RSSs with better calibration to predict outcomes.

[Computer modeling of the area of carotid endarterectomy with patches of various forms]

OBJECTIVE

To describe geometric models of carotid artery bifurcation and computer modeling of carotid endarterectomy (CEA) with patches of various configurations.

MATERIAL AND METHODS

The method was demonstrated on a reconstructed model of intact vessel based on preoperative CT of the affected vessel in a certain patient. Blood flow is modeled by computational fluid dynamics using Doppler ultrasound data. Risk factors were assessed considering hemodynamic parameters of vascular wall associated with WSS.

RESULTS

We studied hemodynamic results of 10 virtual CEA with patches of various shapes on the example of a reconstructed intact artery in a particular patient. Patch implantation is aimed at prevention of carotid artery narrowing since simple suture without a patch can reduce circumference of the artery by 4-5 mm. This result adversely affects blood flow. On the other hand, too wide a patch creates aneurysm-like deformation of internal carotid artery bulb. It is not optimal due to a large recirculation zone. It was found that patch width approximately equal to 3 mm ensures an optimal hemodynamic result. Deviations from this median value, both upward and downward, impair hemodynamics while the absence of a patch results the worst result.

CONCLUSION

The proposed computer modeling technique is able to provide a personalized patch selection for CEA with low risk of restenosis in long-term follow-up period.

Detection of asymptomatic carotid stenosis in patients with lower-extremity arterial disease: development and external validations of a risk score

BACKGROUND

Recommendations for screening patients with lower-extremity arterial disease (LEAD) to detect asymptomatic carotid stenosis (ACS) are conflicting. Prediction models might identify patients at high risk of ACS, possibly allowing targeted screening to improve preventive therapy and compliance.

METHODS

A systematic search for prediction models for at least 50 per cent ACS in patients with LEAD was conducted. A prediction model in screened patients from the USA with an ankle : brachial pressure index of 0.9 or less was subsequently developed, and assessed for discrimination and calibration. External validation was performed in two independent cohorts, from the UK and the Netherlands.

RESULTS

After screening 4907 studies, no previously published prediction models were found. For development of a new model, data for 112 117 patients were used, of whom 6354 (5.7 per cent) had at least 50 per cent ACS and 2801 (2.5 per cent) had at least 70 per cent ACS. Age, sex, smoking status, history of hypercholesterolaemia, stroke/transient ischaemic attack, coronary heart disease and measured systolic BP were predictors of ACS. The model discrimination had an area under the receiver operating characteristic (AUROC) curve of 0.71 (95 per cent c.i. 0.71 to 0.72) for at least 50 per cent ACS and 0.73 (0.72 to 0.73) for at least 70 per cent ACS. Screening the 20 per cent of patients at greatest risk detected 12.4 per cent with at least 50 per cent ACS (number needed to screen (NNS) 8] and 5.8 per cent with at least 70 per cent ACS (NNS 17). This yielded 44.2 and 46.9 per cent of patients with at least 50 and 70 per cent ACS respectively. External validation showed reliable discrimination and adequate calibration.

CONCLUSION

The present risk score can predict significant ACS in patients with LEAD. This approach may inform targeted screening of high-risk individuals to enhance the detection of ACS.

Machine learning for detection of stenoses and aneurysms: application in a physiologically realistic virtual patient database

This study presents an application of machine learning (ML) methods for detecting the presence of stenoses and aneurysms in the human arterial system. Four major forms of arterial disease-carotid artery stenosis (CAS), subclavian artery stenosis (SAS), peripheral arterial disease (PAD), and abdominal aortic aneurysms (AAA)-are considered. The ML methods are trained and tested on a physiologically realistic virtual patient database (VPD) containing 28,868 healthy subjects, adapted from the authors previous work and augmented to include disease. It is found that the tree-based methods of Random Forest and Gradient Boosting outperform other approaches. The performance of ML methods is quantified through the [Formula: see text] score and computation of sensitivities and specificities. When using six haemodynamic measurements (pressure in the common carotid, brachial, and radial arteries; and flow-rate in the common carotid, brachial, and femoral arteries), it is found that maximum [Formula: see text] scores larger than 0.9 are achieved for CAS and PAD, larger than 0.85 for SAS, and larger than 0.98 for both low- and high-severity AAAs. Corresponding sensitivities and specificities are larger than 90% for CAS and PAD, larger than 85% for SAS, and larger than 98% for both low- and high-severity AAAs. When reducing the number of measurements, performance is degraded by less than 5% when three measurements are used, and less than 10% when only two measurements are used for classification. For AAA, it is shown that [Formula: see text] scores larger than 0.85 and corresponding sensitivities and specificities larger than 85% are achievable when using only a single measurement. The results are encouraging to pursue AAA monitoring and screening through wearable devices which can reliably measure pressure or flow-rates.

Cost-Effectiveness of TransCarotid Artery Revascularization versus Carotid Endarterectomy

OBJECTIVES

Recent studies have demonstrated that TransCarotid Artery Stenting (TCAR) has comparable outcomes to the surgical gold standard, carotid endarterectomy (CEA). However, few studies have analyzed the cost of TCAR and no study has evaluated its cost-effectiveness. The purpose of this study is to conduct a cost-effectiveness analysis comparing TCAR to CEA for carotid artery stenosis.

METHODS

We built a Markov microsimulation using transition probabilities and utilities from existing literature for symptomatic patients undergoing TCAR or CEA. Costs were derived from literature then converted to 2019 dollars. The model included six health states with monthly cycle lengths: surgery, death, alive after surgery, alive after myocardial infarction, alive after stroke, and alive after stroke and death. Quality adjusted life years (QALYs), costs, and incremental cost-effectiveness ratio (ICER) were analyzed over a five-year period. One-way sensitivity and probabilistic sensitivity analyses were conducted to study the impact of parameter variability on cost effectiveness.

RESULTS

For symptomatic patients, CEA cost $7821 for 2.85 QALYs while TCAR cost $19154 for 2. 92 QALYs, leading to an ICER of $152,229 per QALY gained in the TCAR arm Sensitivity analysis demonstrated that our model was most sensitive to probability of restenosis, costs of TCAR and costs of CEA. Probabilistic sensitivity analysis demonstrated TCAR would be considered cost effective 49% of iterations.

CONCLUSIONS

This study found that while five-year costs for TCAR were greater than CEA, TCAR afforded greater QALYs than CEA. TCAR became cost-effective at six-years follow-up.

Potential of machine learning to predict early ischemic events after carotid endarterectomy or stenting: a comparison with surgeon predictions

Carotid endarterectomy (CEA) and carotid artery stenting (CAS) are recommended for high stroke-risk patients with carotid artery stenosis to reduce ischemic events. However, we often face difficulty in determining the best treatment strategy. We aimed to develop an accurate post-CEA/CAS outcome prediction model using machine learning that will serve as a basis for a new decision support tool for patient-specific treatment planning. Retrospectively collected data from 165 consecutive patients with carotid stenosis underwent CEA or CAS and were divided into training and test samples. The following five machine learning algorithms were tuned, and their predictive performance was evaluated by comparison with surgeon predictions: an artificial neural network, logistic regression, support vector machine, random forest, and extreme gradient boosting (XGBoost). Seventeen clinical factors were introduced into the models. Outcome was defined as any ischemic stroke within 30 days after treatment including asymptomatic diffusion-weighted imaging abnormalities. The XGBoost model performed the best in the evaluation; its sensitivity, specificity, positive predictive value, and accuracy were 31.9%, 94.6%, 47.2%, and 86.2%, respectively. These statistical measures were comparable to those of surgeons. Internal carotid artery peak systolic velocity, low-density lipoprotein cholesterol, and procedure (CEA or CAS) were the most contributing factors according to the XGBoost algorithm. We were able to develop a post-procedural outcome prediction model comparable to surgeons in performance. The accurate outcome prediction model will make it possible to make a more appropriate patient-specific selection of CEA or CAS for the treatment of carotid artery stenosis.

Acute monocular vision loss as presenting symptom of delayed stroke from internal carotid occlusion in COVID-19

Covid-19 infection has been declared a pandemic by the World Health Organization. We present a unique case of a middle-aged gentleman, who recovered from asymptomatic Covid-19 infection and presented again with delayed stroke. He had vision loss secondary to internal carotid artery occlusion in the absence of neurological symptoms. To the best of our knowledge, this is the first case that describes cerebrovascular stroke due to delayed large vessel occlusion secondary to Covid-19 infection presenting as monocular vision loss.

Optimal Carotid Plaque Features on Computed Tomography Angiography Associated With Ischemic Stroke

Background Stenosis has historically been the major factor used to determine carotid stroke sources. Recent evidence suggests that specific plaque features detected on imaging may be more highly associated with ischemic stroke than stenosis. We sought to determine computed tomography angiography (CTA) imaging features of carotid plaque that optimally discriminate ipsilateral stroke sources. Methods and Results In this institutional review board-approved retrospective cross-sectional study, 494 ipsilateral carotid CTA-brain magnetic resonance imaging pairs were available for analysis after excluding patients with alternative stroke sources. Carotid CTA and clinical markers were recorded, a multivariable Poisson regression model was fitted, and backward elimination was performed with a 2-sided threshold of P<0.10. Discriminatory value was determined using receiver operating characteristic analysis, area under the curve, and bootstrap validation. The final CTA carotid-source stroke prediction model included intraluminal thrombus (prevalence ratio, 2.8 [P<0.001]; 95% CI, 1.6-4.9), maximum soft plaque thickness (prevalence ratio, 1.2 [P<0.001]; 95% CI, 1.1-1.4), and the rim sign (prevalence ratio, 2.0 [P=0.007]; 95% CI, 1.2-3.3). The final discriminatory value (area under the curve=78.3%) was higher than intraluminal thrombus (56.4%, P<0.001), maximum soft plaque thickness (76.4%, P=0.007), or rim sign alone (69.9%, P=0.001). Furthermore, NASCET (North American Symptomatic Carotid Endarterectomy Trial) stenosis categories (cutoffs of 50% and 70%) had lower stroke discrimination (area under the curve=67.4%, P<0.001). Conclusions Optimal discrimination of ipsilateral carotid sources of stroke requires information on intraluminal thrombus, maximum soft plaque thickness, and the rim sign. These results argue against the sole use of carotid stenosis to determine stroke sources on CTA, and instead suggest these alternative markers may better diagnose vulnerable carotid plaque and guide treatment decisions.

Relationship Between Acute Neurological Function and Long-Term Prognosis in Patients with Large Arterial Occlusions

OBJECTIVES

To clarify the relationship between early neurological symptoms and long-term functional outcomes of acute ischemic stroke, which would be beneficial for patient management and determining clinical study criteria of novel therapeutic interventions.

MATERIALS AND METHODS

We retrieved data from the Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism Japan Registry 2 (RESCUE-Japan Registry 2) and investigated the association between 24- and 72-hour National Institutes of Health Stroke Scale (NIHSS) and 90-day modified Rankin Scale (mRS) scores, stratified by the site of occlusion (carotid or vertebrobasilar circulatory large arterial occlusion [ACO or PCO, respectively]) and endovascular recanalization therapy (EVT) performance. We examined the correlation using Spearman's rank correlation coefficient (rho). Predictive accuracies of 24- and 72-hour NIHSS scores for good outcomes at 90 days (defined as mRS score of 0-2) were evaluated by receiver operating characteristic (ROC) analyses and the corresponding areas under the curves (AUCs).

RESULTS

Among the 2420 patients, 1745 had ACO (971 with EVT, 774 without EVT) and 263 had PCO (127 with EVT, 136 without EVT). The 24- and 72-hour NIHSS scores were significantly associated with 90-day mRS scores and accurately predicted good outcomes (all rhos ≥0.76, all AUCs ≥0.86). In the ACO group, there were differences in rho and AUC depending on EVT performance and the time from onset to NIHSS acquisition, but no differences were observed in the PCO group.

CONCLUSIONS

EVT performance and time frame should be considered when determining the criteria of novel therapeutic interventions, especially for patients with ACO.

Robot-Assisted Carotid Artery Stenting: A Safety and Feasibility Study

PURPOSE

Endovascular robotics is an emerging technology within the developing field of medical robotics. This was a prospective evaluation to assess safety and feasibility of robotic-assisted carotid artery stenting.

MATERIALS AND METHODS

Consecutive cases of carotid artery stenting cases performed over period of 24 months, from May 2015 to October 2016, using the Magellan Robotic System (Hansen, Mountain View, CA) were included. All cases utilised the robotic system to navigate the arch, obtain a stable position in the common carotid artery, followed by manual manipulation of Embolic Protection Devices and self-expandable stents through the robotic catheter. Patients demographics, clinical indications, anatomical features, technical and clinical success, complication rate and hospital stay were prospectively recorded.

RESULTS

Thirteen patients, 10 males (78.5%), with an average age of 68.7 years were treated. Mean follow up time was 30 months. Ten patients (91%) were symptomatic at presentation. Anatomical indications for endovascular stent insertion were previous open surgery to the neck ± radiotherapy (87.5%) and hostile anatomy for open surgery (12.5%). Technical success was 100% and the robotic system demonstrates enhanced stability during arch and lesion crossing. There were no neurological complications post-operatively. Average hospital stay was 3 days (range 2-6 days) and a change in serum creatinine of -7.8 μmol/L. There was no documented case of in stent restenosis, new or worsening neurology during follow-up.

CONCLUSION

These results illustrate safety and feasibility of robotic endovascular revascularisation for carotid disease and demonstrates potential to enhance peri-procedural safety through improved control and stability.

Circulating miR-27b as a Biomarker of the Development and Progression of Carotid Artery Stenosis

OBJECTIVE

A close relationship of microRNAs (miRNAs) with various human diseases has been widely reported, including cardiovascular disease. The current study attempted to examine the abnormal expression of miR-27b in asymptomatic carotid artery stenosis (ACAS), its diagnostic value and predictive value for the development of ACAS were also assessed.

METHODS

Clinical serum samples were collected from both ACAS patients and healthy individuals, and levels of miR-27b in the clinical samples were detected using Real-time quantitative PCR. Cerebral ischemia events (CIEs) of patients during the 5-year follow-up were collected. The diagnostic and predictive values of serum miR-27b was assessed via plotting Receiver operating characteristic (ROC) and Kaplan-Meier curves. Multivariate cox regression analysis was performed for clinical independent index analysis.

RESULTS

ACAS patients had higher levels of miR-27b than the healthy subjects. There were close association of serum miR-27b levels with total cholesterol (TC) level, absence of hypertension and degree of carotid stenosis. High levels of miR-27b could differentiate ACAS cases from healthy subjects, and predicted the high incidence of CIEs. MiR-27b could be used as an independent predictor of cerebrovascular events via multiple Cox regression analysis (P = .031).

CONCLUSION

The high level of miR-27b can predict the occurrence of ACAS, and is closely related to the subsequent occurrence of CIEs. The present results provide evidence for circulating miR-27b as a diagnostic and prognostic marker in patients with ACAS.

Detection of Asymptomatic Carotid Artery Stenosis in High-Risk Individuals of Stroke Using a Machine-Learning Algorithm

Objective Asymptomatic carotid stenosis (ACS) is closely associated to the incidence of severe cerebrovascular diseases. Early identifying the individuals with ACS and its associated risk factors could be beneficial for primary prevention of stroke. This study aimed to investigate a machine-learning algorithm for the detection of ACS among high-risk population of stroke based on the associated risk factors.Methods A novel model of machine learning was utilized to screen the associated predictors of ACS based on 30 potential risk factors. The algorithm of this model adopted a random forest pattern based on the training data and then was verified using the testing data. All of the original data were retrieved from the China National Stroke Screening and Prevention Project (CNSSPP), including demographic, clinical and laboratory characteristics. The individuals with high risk of stroke were enrolled and randomly divided into a training group and a testing group at a ratio of 4:1. The identification of carotid stenosis by carotid artery duplex scans was set as the golden standard. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) was used to evaluate the efficacy of the model in detecting ACS.Results Of 2841 high risk individual of stroke enrolled, 326 (11.6%) were diagnosed as ACS by ultrasonography. The top five risk factors contributing to ACS in this model were identified as family history of dyslipidemia, high level of low-density lipoprotein cholesterol (LDL-c), low level of high-density lipoprotein cholesterol (HDL-c), aging, and low body mass index (BMI). Their weights were 11.8%, 7.6%, 7.1%, 6.1%, and 6.1%, respectively. The total weight of the top 15 risk factors was 85.5%. The AUC values of the model for detecting ACS with training dataset and testing dataset were 0.927 and 0.888, respectively.Conclusions This study demonstrated that the machine-learning algorithm could be used to identify the risk factors for ACS among high risk population of stroke. Family history of dyslipidemia may be the most important risk factor for ACS. This model could be a suitable tool to optimize the clinical approach for the primary prevention of stroke.

Different clinical courses of various radiologic findings in fibromuscular dysplasia during a 7-year follow-up: A case report

RATIONALES

The natural history of fibromuscular dysplasia (FMD) is unclear. Furthermore, the correlation between radiologic findings and clinical significance has not been documented. Previously, the development of new vascular symptoms was reported in a small number of patients, but some of these symptoms were from other vascular causes. New arterial lesions were rarely observed during follow-up in the previous reports.

PATIENT CONCERNS

A 40-year-old man was admitted due to dysarthria and left-sided weakness. He had developed flank pain due to bilateral renal infarction about 10 months earlier. He had no known risk factors for atherosclerosis. Initial neurological examination revealed a mild weakness and central facial palsy on the left side.

DIAGNOSES

Diffusion-weighted magnetic resonance imaging revealed a small acute infarction in the right insular cortex. Magnetic resonance angiography and digital subtraction angiography showed a severe stenosis with post-dilatation in the right internal carotid artery (ICA). There was a focal ectatic lesion in the left ICA. On the previous abdominal computed tomography angiography (CTA), there were arterial lesions suggestive of dissection in the bilateral renal arteries and a rod-shaped ectasia in the left common iliac artery (CIA). The pathological diagnosis was mixed-type FMD involving the intima and media.

INTERVENTIONS

The patient was prescribed antiplatelet agents for prevention of further ischemic events and followed up regularly.

OUTCOMES

Seven years after the initial renal infarction, the patient developed abdominal pain radiating to the back. Abdominal CTA revealed that an aortic dissection had developed in the infrarenal aorta, which was shown as normal previously. The ectasia in the left CIA and left ICA showed no interval changes during follow-up.

LESSONS

We present a patient who developed spontaneous symptomatic dissection of the bilateral renal arteries, right ICA, and abdominal aorta during 7 years of follow-up, which were caused by pathologically confirmed FMD. Besides the symptomatic multifocal dissection, the patient showed an asymptomatic multifocal ectasia on cerebral and abdominal angiographies that had not changed over 7 years.

A Machine Learning Approach for Predicting Early Phase Postoperative Hypertension in Patients Undergoing Carotid Endarterectomy

BACKGROUND

This study aimed to establish and validate a machine learning-based model for the prediction of early phase postoperative hypertension (EPOH) requiring the administration of intravenous vasodilators after carotid endarterectomy (CEA).

METHODS

Perioperative data from consecutive CEA procedures performed from January 2013 to August 2019 were retrospectively collected. EPOH was defined in post-CEA patients as hypertension involving a systolic blood pressure above 160 mm Hg and requiring the administration of any intravenous vasodilator medications in the first 24 hr after a return to the vascular ward. Gradient boosted regression trees were used to construct the predictive model, and the featured importance scores were generated by using each feature's contribution to each tree in the model. To evaluate the model performance, the area under the receiver operating characteristic curve was used as the main metric. Four-fold stratified cross-validation was performed on the data set, and the average performance of the 4 folds was reported as the final model performance.

RESULTS

A total of 406 CEA operations were performed under general anesthesia. Fifty-three patients (13.1%) met the definition of EPOH. There was no significant difference in the percentage of postoperative stroke/death between patients with and without EPOH during the hospital stay. Patients with EPOH exhibited a higher incidence of postoperative cerebral hyperperfusion syndrome (7.5% vs. 0, P < 0.001), as well as a higher incidence of cerebral hemorrhage (3.8% vs. 0, P < 0.001). The gradient boosted regression trees prediction model achieved an average AUC of 0.77 (95% CI 0.62 to 0.92). When the sensitivity was fixed near 0.90, the model achieved an average specificity of 0.52 (95% CI 0.28 to 0.75).

CONCLUSIONS

We have built the first-ever machine learning-based prediction model for EPOH after CEA. The validation result from our single-center database was very promising. This novel prediction model has the potential to help vascular surgeons identify high-risk patients and reduce related complications more efficiently.

Validation of Risk Prediction Models to Detect Asymptomatic Carotid Stenosis

Background Significant asymptomatic carotid stenosis (ACS) is associated with higher risk of strokes. While the prevalence of moderate and severe ACS is low in the general population, prediction models may allow identification of individuals at increased risk, thereby enabling targeted screening. We identified established prediction models for ACS and externally validated them in a large screening population. Methods and Results Prediction models for prevalent cases with ≥50% ACS were identified in a systematic review (975 studies reviewed and 6 prediction models identified [3 for moderate and 3 for severe ACS]) and then validated using data from 596 469 individuals who attended commercial vascular screening clinics in the United States and United Kingdom. We assessed discrimination and calibration. In the validation cohort, 11 178 (1.87%) participants had ≥50% ACS and 2033 (0.34%) had ≥70% ACS. The best model included age, sex, smoking, hypertension, hypercholesterolemia, diabetes mellitus, vascular and cerebrovascular disease, measured blood pressure, and blood lipids. The area under the receiver operating characteristic curve for this model was 0.75 (95% CI, 0.74-0.75) for ≥50% ACS and 0.78 (95% CI, 0.77-0.79) for ≥70% ACS. The prevalence of ≥50% ACS in the highest decile of risk was 6.51%, and 1.42% for ≥70% ACS. Targeted screening of the 10% highest risk identified 35% of cases with ≥50% ACS and 42% of cases with ≥70% ACS. Conclusions Individuals at high risk of significant ACS can be selected reliably using a prediction model. The best-performing prediction models identified over one third of all cases by targeted screening of individuals in the highest decile of risk only.

Rationale for screening selected patients for asymptomatic carotid artery stenosis

Stroke is a leading cause of death and disability worldwide. Approximately 15% of all first-ever strokes occur due to atheroembolism from a previously undetected/untreated asymptomatic carotid stenosis (ACS). Despite that, international guidelines do not recommend screening for ACS. The rationale for not recommending screening include: (a) the harm associated with screening, (b) the questionable clinical benefit associated with surgery, (c) the lack of proven reduction in the risk of stroke, (d) the large number of false positive/false negative tests, and (e) the cost-effectiveness of such screening programs. A critical analysis of each of these arguments is presented. Patients with ACS have a very high risk of all-cause and cardiac mortality. Detection of ACS should not be viewed as an indication for surgery, but rather as an opportunity to implement best medical treatment (BMT) and lifestyle changes to prevent not only strokes, but also cardiac events. The implementation of screening programs for abdominal aortic aneurysms (AAAs) has led to a considerable reduction in the number of ruptured AAAs and AAA-related deaths. Similarly, screening high-risk individuals for ACS would enable timely identification of patients with ACS and implementation of BMT and lifestyle measures to prevent future strokes and cardiac events.

Comparison of digital subtraction angiography and contrast-enhanced ultrasound in assessment of carotid stenosis

INTRODUCTION

The performances of contrast-enhanced ultrasound (CEUS) and digital subtraction angiography (DSA) were used to establish an efficient as well as non-invasive clinical technique for the diagnosis of extra-cranial internal carotid artery (ICA) stenosis.

MATERIALS AND METHODS

Thirty-six successive patients (11 women and 25 men, mean age: 65.0 ± 9.2, range: 43-78 years) with internal carotid artery (ICA) stenosis were tested by CEUS and DSA. These tests were carried out by means of Hitachi Preirus ultrasound machine for CEUS and Allura Xper FD20 system (Philips Medical Systems, Nederland B.V.) for DSA. 1.2 ml SonoVue (Bracco, Switzerland) was used a s contrast agent.

RESULTS

The results clearly indicated that there were no noteworthy variations among the distributions recorded by CEUS as well as DSA for the four tested groups. The percentage of diameter stenosis calculated by CEUS was clearly in accordance with the DSA images. CEUS showed accurate results with good specificity and sensitivity at 50%, 70%, and 100%. Also, CEUS performance was relatively better than DSA in the diagnosis of ICA and suitability of CEA.

CONCLUSION

CEUS proved to be a precise non-invasive testing method for the diagnosis of carotid artery stenosis which is more feasible and well-tolerated in patients with various stages of carotid stenosis.

The usefulness of Time-of-Flight MR angiography in detection of intraplaque hemorrhage in patients with acute ischemic stroke with symptomatic carotid stenosis

Objective

Carotid intraplaque hemorrhage (IPH) is a well-known risk indicator of thromboembolism, but it is not easy to rapidly detect IPH in acute symptomatic carotid disease. The aim of this study was to assess the utility of time-of-flight (TOF) magnetic resonance angiography (MRA) in the detection of IPH and evaluate the degree of stenosis and stroke patterns in patients with acute symptomatic carotid disease.

Methods

We retrospectively identified consecutive patients with acute symptomatic carotid disease who were admitted within 12 h after stroke onset. Fifty-nine patients underwent TOF MRA at admission and were categorized according to the presence or absence of intraplaque high signal intensity (HSI). The severity of carotid stenosis and diffusion-weighted magnetic resonance imaging lesion patterns were evaluated.

Results

Intraplaque HSI was detected in 28.8% of the enrolled patients (17/59). Mild-to-moderate symptomatic carotid stenosis was more frequent in the intraplaque HSI-positive group (70.6%) than in the intraplaque HSI-negative group (42.8%) (p = 0.015). The patients with intraplaque HSI more frequently exhibited a disseminated small infarction pattern (76.5% in the intraplaque HSI-positive group, 47.6% in the -negative group), and did not exhibit a border-zone infarction pattern (0% in the positive group, 16.7% in the negative group).

Conclusions

TOF MRA may be a useful noninvasive and rapid tool to detect IPH in patients with acute symptomatic carotid disease. IPH was common in those with a lower degree of carotid stenosis and manifested as a disseminated small infarction pattern. Intraplaque HSI on TOF MRA in acute symptomatic carotid disease may help to determine the mechanism of stroke and establish early treatment plans.

Carotid near-occlusion is often overlooked when CT angiography is assessed in routine practice

Objective

Assess the sensitivity and specificity of computed tomography angiography (CTA) for carotid near-occlusion diagnosis interpreted in clinical practice against expert assessment.

Methods

CTAs were graded by two expert interpreters for near-occlusion. Findings were compared with clinical reports in 383 consecutive cases with symptomatic ≥ 50% carotid stenosis. In addition, 14 selected CTA exams (8 near-occlusions and 6 controls) were analyzed in a national effort by 13 radiologists experienced with carotid CTA.

Results

In clinical practice, imaging reports were 20% (95% CI 12–28%) sensitive for near-occlusion, ranging 0–58% between different radiologists; specificity was 99%. Among the 13 radiologists reviewing the same 8 near-occlusions, the average sensitivity was 8%, ranging 0–75%; specificity was 100%.

Conclusions

Carotid near-occlusion is systematically under-reported in clinical routine practice, caused by limited application of grading criteria when assessing CTA.

Key Points

• Carotid near-occlusion is severe stenosis with distal artery collapse; this collapse is often subtle.

• A fifth of near-occlusions were detected in routine practice. Many readers mistake near-occlusion for stenosis without distal artery collapse, either by not actively searching for subtle collapses or by not interpreting the collapse correctly when noticed.

• On the other hand, the novice diagnostician should be cautioned to not over-diagnose near-occlusion; other causes of extracranial ICA asymmetry also exist such as distal disease and Circle of Willis anatomical variants.

[Risk factors for adverse clinical events after carotid arteries stenting in elderly and senile patients.]

The safety of the use of carotid arteries stenting (CAS) in elderly and senile patients remains a controversial issue. The reasons for the development of adverse events in this group of patients after CAS surgical procedure are unknown. The purpose of this study was to evaluate the risk factors for the development of adverse clinical events after CAS surgical procedure in elderly patients group. The study included 147 patients (94 men, 53 women, average age -- 72,1±3,5 years) of elderly and senile patients hospitalized to perform CAS for stenosis of the carotid arteries. According to the constructed model of binary logistic regression, the following parameters are statistically significantly associated with the development of complications after CAS: the presence of stroke in the anamnesis (p=0,013), symptomatic stenosis of the carotid arteries (p=0,011) and the degree of disability according to mRS (Modified Rankin Scale) ≥3 (p=0,002). In order to identify the identified risk factors and minimize the incidence of complications in elderly patients who underwent CAS surgery, a detailed preoperative assessment of their somatic status is necessary with an emphasis on the state of the cardiovascular system.

Atherosclerotic ICA stenosis coinciding with ICA asymmetry associated with Circle of Willis variations can mimic near-occlusion

Differentiating carotid near-occlusion (tight atherosclerotic stenosis causing distal artery size reduction) from conventional stenosis is the first step when grading carotid stenoses with NASCET method. The internal carotid artery (ICA) can be asymmetrically associated with Circle of Willis variations. When such ICA asymmetry coincides with stenosis, it may mimic near-occlusion. We studied ICA anatomical variant prevalence in 4042 consecutive CTA exams from all indications, 53 excluded due to carotid occlusion, 814 with any ≥ 50% steno-occlusive disease intra- or extracranially, 3228 without. Of the 3989 included cases, 568 (14%) had ICA asymmetry, of which 335 (59%) were from associated with Circle of Willis variations. Of 3228 patients without ≥ 50% stenosis or other steno-occlusive disease intra- and extracranially; 257 (8.0%) demonstrated ICA asymmetry associated with Circle of Willis variations, equally common among sexes and age unrelated and most frequently attributed to an ipsilateral A1 hypoplasia/aplasia, less often attributed to large contralateral posterior communicating artery. As ICA asymmetry associated with Circle of Willis variations are common, caution should be exercised diagnosing near-occlusion on asymmetry alone.

Does Quantification of Carotid Plaque Surface Irregularities Better Detect Symptomatic Plaques Compared to the Subjective Classification?

OBJECTIVES

To evaluate the interobserver agreement of color Doppler ultrasound (CDUS) and contrast-enhanced ultrasound (CEUS) for quantification of carotid plaque surface irregularities and to correlate objective and subjective measures with stroke occurrence.

METHODS

This work was an observational study involving 54 patients with 62 internal carotid artery or carotid bulb plaques (31 symptomatic) undergoing CDUS and CEUS between February 2016 and February 2018, with retrospective interpretation of prospectively acquired data. Plaques were included if causing moderate (50%-69%) or severe (70%-99%) stenosis based on velocity criteria, and their surface was classified as smooth, irregular, or ulcerated based on CEUS. The surface irregularities were quantified in the form of a surface irregularity index by 2 observers, based on CDUS and CEUS. The surface irregularity index was evaluated for interobserver agreement with CDUS and CEUS and correlated with the occurrence of stroke, as was the subjective characterization of the plaque surface.

RESULTS

Color Doppler ultrasound and CEUS showed good interobserver agreement (intraclass correlation coefficients, 0.979 and 0.952, respectively). Plaques were characterized as smooth in 30.6% of cases, irregular in 50%, and ulcerated in 19.4%. The subjective classification of the plaque surface did not correlate with stroke occurrence (P > .05, χ² ). Surface irregularity index values were significantly higher for symptomatic plaques with both CDUS and CEUS (P < .05).

CONCLUSIONS

Color Doppler ultrasound and CEUS can quantify carotid plaque surface irregularities with good interobserver agreement. The resulting quantitative measure was significantly higher in symptomatic plaques, whereas the subjective characterization of plaque surface failed to differ between symptomatic and asymptomatic plaques.

Carotid Artery Stenosis after Radiation Therapy in a Patient with Lung Cancer: A Case Report and Literature Review

We reported a case of carotid artery stenosis with stroke symptoms detected in a patient with lung cancer after radiotherapy. The patient was a 58-year-old male with a complaint of \"a single episode of temporary amaurosis in the right eye for 10 minutes". The clinical diagnosis at admission, after consideration of the patient's age, medical history, and auxiliary examination results, was as follows: lung cancer; right common carotid artery stenosis; left common carotid artery stenosis; left vertebral artery stenosis; and right subclavian artery occlusion with right subclavian steal syndrome (Grade 3). Carotid angioplasty and stenting (CAS) were subsequently performed. During the 6-month follow-up, we observed no episode of temporary vision loss or other signs of stroke. Clinicians should pay great attention to delayed radiation-induced carotid stenosis. It is recommended that patients with a history of radiotherapy should undergo regular color Doppler ultrasound examination of the cervical region to diagnose, prevent, and treat RICS in an expedient fashion. This approach should improve survival rate and quality of life.

Lagrangian carotid strain imaging indices normalized to blood pressure for vulnerable plaque

OBJECTIVE

Ultrasound Lagrangian carotid strain imaging (LCSI) utilizes physiological deformation caused by arterial pressure variations to generate strain tensor maps of the vessel walls and plaques. LCSI has been criticized for the lack of normalization of magnitude-based strain indices to physiological stimuli, namely blood pressure. We evaluated the impact of normalization of magnitude-based strain indices to blood pressure measured immediately after the acquisition of radiofrequency (RF) data loops for LCSI.

MATERIALS AND METHODS

A complete clinical ultrasound examination along with RF data loops for LCSI was performed on 50 patients (30 males and 20 females) who presented with >60% carotid stenosis and were scheduled for carotid endarterectomy. Cognition was assessed using the 60-minute neuropsychological test protocol.

RESULTS

For axial strains correlation of maximum accumulated strain indices (MASI), cognition scores were -0.46 for non-normalized and -0.45, -0.49, -0.37, and -0.48 for systolic, diastolic, pulse pressure, and mean arterial pressure normalized data, respectively. The corresponding area under the curve (AUC) values for classifiers designed using maximum likelihood estimation of a binormal distribution with a median-split of the executive function cognition scores were 0.73, 0.70, 0.71, 0.70, and 0.71, respectively.

CONCLUSIONS

No significant differences in the AUC estimates were obtained between normalized and non-normalized magnitude-based strain indices.

New Quantitative Digital Image Analysis Method of Histological Features of Carotid Atherosclerotic Plaques

OBJECTIVE

Atherosclerosis and its thrombotic complications are major causes of morbidity and mortality worldwide. Plaque stability assessment is considered to be important for both clinical and fundamental applications. The current gold standard method to investigate plaque stability is performed by histological assessment of plaque features using semi-quantitative classifications. However, these assessments can be limited by subjectivity and variability. Thus, the aim was to develop a new digital image analysis method to measure quantitatively individual plaque features that is more precise than existing semi-quantitative methods.

METHODS

A quantitative method was developed using Image Pro Primer software. Carotid plaque specimens were obtained from patients who underwent carotid endarterectomy and categorised according to stability (definitely stable, probably stable, probably unstable, definitely unstable) based on the gold standard semi-quantitative method that assesses 10 histological plaque features. Using the new quantitative method, plaque features (n = 15) from each stability grade were then analysed by two independent raters. For the semi-quantitative analysis, quadratic weighted Cohen's kappa was used to test intra- and inter-rater reliability, while for the quantitative analysis, intraclass correlation coefficients (ICCs) were assessed.

RESULTS

Intra-rater reliability demonstrated almost perfect agreement between both methods (Cohen's kappa range 0.831-0.969, ICC range 0.848-1.000). However, inter-rater reliability demonstrated mainly fair to moderate agreement (Cohen's kappa range 0.341-0.778) for the semi-quantitative analysis, while the digital image analysis method performed most optimally regarding reproducibility, yielding high ICCs close to 1 (ICC range 0.816-0.999). Using quantitative measurements, a statistically significant proportion of the individual plaque features (p < .05) were re-classified from one grade to another (shift by one) under the semi-quantitative classification.

CONCLUSION

A new quantitative digital image analysis was developed for the accurate assessment of histological plaque features, which demonstrated higher precision than the gold standard semi-quantitative methods, as measured by between and within rater analysis. Moreover, quantitative image analysis of histological plaque features provided more detailed insight into plaque morphology and composition.

Infrared (IR) thermography as a potential screening modality for carotid artery stenosis

In the present study, an infrared (IR) thermal camera was used to map the temperature of the target skin surface, and the resulting thermal image was evaluated for the presence of carotid artery stenosis (CAS). In the presence of stenosis in the carotid artery, abnormal temperature maps are expected to occur on the external skin surface, which could be captured and quantified using IR thermography. A Duplex Ultrasound (DUS) examination was used to establish the ground truth. In each patient, the background-subtracted thermal image, referred to as full thermal image, was used to extract novel parametric cold thermal feature images. From these images, statistical features, viz., correlation, energy, homogeneity, contrast, entropy, mean, standard deviation (SD), skewness, and kurtosis, were calculated and the two groups of patients (control and diseased: a total of 80 carotid artery samples) were classified. Both cut-off value- and support vector machine (SVM)-based binary classification models were tested. While the cut-off value classification model resulted in a moderate performance (70% accurate), SVM was found to have classified the patients with high accuracy (92% or higher). This preliminary study suggests the potential of IR thermography as a possible screening tool for CAS patients.

Added assessment of middle cerebral artery and atrial fibrillation to FLAIR vascular hyperintensity-DWI mismatch would improve the outcome prediction of acute infarction in patients with acute internal carotid artery occlusion

BACKGROUND AND AIMS

Whether fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVH)-DWI mismatch could predict the outcome or not remains in debate. The aim of this study was to identify if FVH combined with the other markers improved favorable outcome prediction of acute infarctions in patients with unilateral acute internal carotid artery (ICA) occlusion.

METHODS

Consecutive 68 adult acute middle cerebral artery (MCA) territory infarction patients caused by acute ICA occlusion, including favorable (n = 38, mRS ≤ 2) and unfavorable (n = 30, mRS > 2) groups, were enrolled in this retrospective analysis. The diagnostic efficiency of favorable clinical outcome of FVH-DWI mismatch was compared with those of DWI lesions volumetry and the combined marker of FVH-DWI mismatch and other factors.

RESULTS

There were more prominent FVH-DWI mismatch (≥ 3 sections) (84%), less atrial fibrillation (AFib) (13%), and more tandem MCA normal or mild stenosis (63%) in favorable outcome group than those (30%, 40%, and 27%, respectively) in unfavorable group. Univariate and multivariate analyses showed that the prominent FVH-DWI mismatch was the positive predictive factor for favorable outcome (OR = 2.643 and 3.200). Prominent FVH-DWI mismatch, in combination with tandem MCA normal or mild stenosis, and absence of Afib, had better performance (AUC = 0.875) than that of initial DWI lesion volumetry (AUC = 0.854) and any other single factor (AUC = 0.634~0.820) in predicting favorable outcome.

CONCLUSIONS

Prominent FVH-DWI mismatch was associated with favorable outcome in acute infarctions in unilateral ICA occlusion patients. Its predictive performance would be improved when combined with the assessment of tandem lesions of MCA and AFib.