Editor's Choice – Predictors of New Ischaemic Brain Lesions on Diffusion Weighted Imaging After Carotid Stenting and Endarterectomy: A Systematic Review

CIRSE Standards of Practice on Carotid Artery Stenting

BACKGROUND

Carotid artery stenting has been used effectively to treat internal carotid artery stenosis since 1989 (Mathias et al. in World J Surg. 25(3):328-34, 2001), with refined and expanded techniques and tools presently delivering outstanding results in percutaneous endoluminal treatment of carotid artery stenosis.

PURPOSE

This CIRSE Standards of Practice document is directed at interventional radiologists and details the guidelines for carotid artery stenting, as well as the different implementation techniques. In addition to updating all previously published material on the different clinical indications, it will provide all technical details reflective of European practice for carotid artery stenting. CIRSE Standards of Practice documents do not aim to implement a standard of clinical patient care, but rather to provide a realistic strategy and best practices for the execution of this procedure.

METHODS

The writing group, which was established by the CIRSE Standards of Practice Committee, consisted of five clinicians with internationally recognised expertise in carotid artery stenting procedures. The writing group reviewed existing literature on carotid artery stenting procedures, performing a pragmatic evidence search using PubMed to select relevant publications in the English language from 2006 to 2022.

RESULTS

Carotid artery stenting has an established role in the management of internal carotid artery stenosis; this Standards of Practice document provides up-to-date recommendations for its safe performance.

Long-Term Stroke Risk in Patients With New Ischemic Brain Lesions on MRI After Carotid Revascularization

BACKGROUND

Carotid artery revascularization can result in new ischemic brain lesions on diffusion-weighted magnetic resonance imaging. This study aimed to investigate the relationship between periprocedural ischemic diffusion-weighted imaging (DWI) lesions after carotid artery revascularization and recurrent long-term cerebrovascular events.

METHODS

A secondary observational prospective cohort analysis of existing clinical trial data was performed on 162 patients with symptomatic carotid stenosis that were previously randomized to carotid artery stenting or carotid endarterectomy in the ICSS (International Carotid Stenting Study) and included in the magnetic resonance imaging substudy. Magnetic resonance imagings were performed 1 to 7 days before and 1 to 3 days after treatment. The primary composite clinical outcome was the time to any stroke or transient ischemic attack during follow-up. Patients with new diffusion-weighted imaging (DWI) lesions on posttreatment magnetic resonance imaging scan (DWI+) were compared with patients without new lesions (DWI-).

RESULTS

The median time of follow-up was 8.6 years (interquartile range, 5.0-12.5). Kaplan-Meier cumulative incidence for the primary outcome after 12.5-year follow-up was 35.3% (SE, 8.9%) in DWI+ patients and 31.1% (SE, 5.6%) in DWI- patients. Uni- and multivariable regression analyses did not show significant differences (hazard ratio, 1.50 [95% CI, 0.76-2.94] and hazard ratio, 1.30 [95% CI, 0.10-1.02], respectively). Higher event rate of the primary outcome in DWI+ patients in the overall cohort was mainly caused by events in the carotid artery stenting group.

CONCLUSIONS

Based on our outcome analysis within the ICSS magnetic resonance imaging substudy, DWI lesions following carotid revascularization did not seem to have a relationship with long-term stroke risk.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: ISRCTN 25337470.

A Propensity-Matched Comparison of Ischemic Brain Lesions on Postprocedural MRI in Endovascular versus Open Carotid Artery Reconstruction

(1) Study purpose: The aim of our prospective single-center, matched case-control study was to compare the number and volume of acute ischemic brain lesions following carotid endarterectomy (CEA) versus carotid artery stenting (CAS) using a propensity-matched design. (2) Methods: Carotid bifurcation plaques were analyzed by using VascuCAP software on CT angiography (CTA) images. The number and volume of acute and chronic ischemic brain lesions were assessed on MRI scans taken 12-48 h after the procedures. Propensity score-based matching was performed at a 1:1 ratio to compare the ischemic lesions on postinterventional MR. (3) Results: A total of 107 patients (CAS, N = 33; CEA, N = 74) were included in the study. There were significant differences in smoking (p = 0.003), total calcification plaque volume (p = 0.004), and lengths of the lesion (p = 0.045) between the CAS and CEA groups. Propensity score matching resulted in 21 matched pairs of patients. Acute ischemic brain lesions were detected in ten patients (47.6%) of the matched CAS group and in three patients (14.2%) in the matched CEA group (p = 0.02). The volume of acute ischemic brain lesions was significantly larger (p = 0.04) in the CAS group than in the CEA group. New ischemic brain lesions were not associated with neurological symptoms in either group. (4) Conclusions: Procedure-related new acute ischemic brain lesions occurred significantly more frequently in the propensity-matched CAS group.

Prediction of new cerebral ischemic lesion after carotid artery stenting: a high-resolution vessel wall MRI-based radiomics analysis

OBJECTIVES

Carotid artery stenting (CAS) is an established treatment for local stenosis. The most common complication is new ipsilateral ischemic lesions (NIILs). This study aimed to develop models considering lesion morphological and compositional features, and radiomics to predict NIILs.

MATERIALS AND METHODS

One hundred and forty-six patients who underwent brain MRI and high-resolution vessel wall MR imaging (hrVWI) before and after CAS were retrospectively recruited. Lumen and outer wall boundaries were segmented on hrVWI as well as atherosclerotic components. A traditional model was constructed with patient clinical information, and lesion morphological and compositional features. Least absolute shrinkage and selection operator algorithm was performed to determine key radiomics features for reconstructing a radiomics model. The model in predicting NIILs was trained and its performance was tested.

RESULTS

Sixty-one patients were NIIL-positive and eighty-five negative. Volume percentage of intraplaque hemorrhage (IPH) and patients' clinical presentation (symptomatic/asymptomatic) were risk factors of NIILs. The traditional model considering these two features achieved an area under the curve (AUC) of 0.778 and 0.777 in the training and test cohorts, respectively. Twenty-two key radiomics features were identified and the model based on these features achieved an AUC of 0.885 and 0.801 in the two cohorts. The AUCs of the combined model considering IPH volume percentage, clinical presentation, and radiomics features were 0.893 and 0.842 in the training and test cohort respectively.

CONCLUSIONS

Compared with traditional features (clinical and compositional features), the combination of traditional and radiomics features improved the power in predicting NIILs after CAS.

KEY POINTS

• Volume percentage of IPH and symptomatic events were independent risk factors of new ipsilateral ischemic lesions (NIILs). • Radiomics features derived from carotid artery high-resolution vessel wall imaging had great potential in predicting NIILs after CAS. • The combination model with radiomics and traditional features further improved the diagnostic performance than traditional features alone.

Absence of the Anterior Communicating Artery on Selective MRA is Associated with New Ischemic Lesions on MRI after Carotid Revascularization

BACKGROUND AND PURPOSE

ICA-selective MRA using a pencil beam presaturation pulse can accurately visualize anterior communicating artery flow. We evaluated the impact of anterior communicating artery flow on the perioperative hemodynamic status and new ischemic lesions after carotid revascularization.

MATERIALS AND METHODS

Eighty-three patients with carotid artery stenosis were included. We assessed anterior communicating artery flow using ICA-selective MRA. The preoperative hemodynamic status was measured using SPECT. We also measured the change in regional cerebral oxygen saturation after temporary ICA occlusion. New ischemic lesions were evaluated by DWI on the day after treatment.

RESULTS

Anterior communicating artery flow was detected in 61 patients, but it was not detected in 22 patients. Preoperative cerebrovascular reactivity was significantly higher in patients with (versus without) anterior communicating artery flow with a mean peak systolic velocity of ≥200 cm/s (39.6% [SD, 23.8%] versus 25.2% [SD, 16.4%]; P = .030). The decrease in mean regional cerebral oxygen saturation was significantly greater in patients without (versus with) anterior communicating artery flow (8.5% [SD, 5.6%] versus 3.7% [SD, 3.8%]; P = .002). New ischemic lesions after the procedure were observed in 23 patients. The multivariate logistic regression analysis revealed that anterior communicating artery flow (OR, 0.07; 95% CI, 0.012-0.45; P = .005) was associated with new ischemic lesions.

CONCLUSIONS

The absence of anterior communicating artery flow influenced the perioperative hemodynamic status in patients with carotid stenosis and was associated with an increased incidence of new ischemic lesions after carotid revascularization.

Guideline on carotid surgery for stroke prevention: updates from the Italian Society of Vascular and Endovascular Surgery. A trend towards personalized medicine

BACKGROUND

This guideline (GL) on carotid surgery as updating of "Stroke: Italian guidelines for Prevention and Treatment" of the ISO-SPREAD Italian Stroke Organization-Group, has recently been published in the National Guideline System and shared with the Italian Society of Vascular and Endovascular Surgery (SICVE) and other Scientific Societies and Patient's Association.

METHODS

GRADE-SIGN version, AGREE quality of reporting checklist. Clinical questions formulated according to the PICO model. Recommendations developed based on clinical questions by a multidisciplinary experts' panel and patients' representatives. Systematic reviews performed for each PICO question. Considered judgements filled by assessing the evidence level, direction, and strength of the recommendations.

RESULTS

The panel provided indications and recommendations for appropriate, comprehensive, and individualized management of patients with carotid stenosis. Diagnostic and therapeutic processes of the best medical therapy, carotid endarterectomy (CEA), carotid stenting (CAS) according to the evidences and the judged opinions were included. Symptomatic carotid stenosis in elective and emergency, asymptomatic carotid stenosis, association with ischemic heart disease, preoperative diagnostics, types of anesthesia, monitoring in case of CEA, CEA techniques, comparison between CEA and CAS, post-surgical carotid restenosis, and medical therapy are the main topics, even with analysis of uncertainty areas for risk-benefit assessments in the individual patient (personalized medicine [PM]).

CONCLUSIONS

This GL updates on the main recommendations for the most appropriate diagnostic and medical-surgical management of patients with atherosclerotic carotid artery stenosis to prevent ischemic stroke. This GL also provides useful elements for the application of PM in good clinical practice.

Staged angioplasty: A sensible approach to prevent hyperperfusion syndrome after carotid artery stenting? A meta-analysis

OBJECTIVE

To investigate whether staged angioplasty (SAP) is a safe and effective treatment to prevent hyperperfusion syndrome after carotid artery stenting (CAS).

METHODS

A systematic literature search was performed according to established criteria to identify eligible articles published before October 2020. Pooled dichotomous data were presented as odds ratios (OR) and corresponding 95% confidence intervals (CI) using random-effect models. The efficacy endpoints were hyperperfusion syndrome (HPS), hyperperfusion phenomenon (HPP), and intracerebral hemorrhage (ICH). The safety endpoint was post-procedural thromboembolic events. The feasibility of the procedure was assessed by device-related adverse events (vessel dissection and failed angioplasty) in SAP.

RESULTS

Ten studies (1030 participants) were eligible. SAP was superior to regular CAS in preventing HPS (OR = 0.35, 95% CI 0.14-0.86, P = 0.02). There was no significant difference in the rate of thromboembolic events between the SAP group and the regular CAS group. The rates of vessel dissection and failed angioplasty with the use of a 3.0-mm-diameter balloon were 5.4% and 0.4%, respectively.

CONCLUSION

SAP may reduce the incidence of post-CAS HPS without increasing procedure-related complications. A 3.0-mm-diameter balloon used in SAP may be appropriate for Asian populations. However, the confounded study design and confused definitions of reporting items hinder the current recommendation of SAP in clinical use.

Computed Tomography Texture Analysis of Carotid Plaque as Predictor of Unfavorable Outcome after Carotid Artery Stenting: A Preliminary Study

Novel biomarkers are advocated to manage carotid plaques. Therefore, we aimed to test the association between textural features of carotid plaque at computed tomography angiography (CTA) and unfavorable outcome after carotid artery stenting (CAS). Between January 2010 and January 2021, were selected 172 patients (median age, 77 years; 112/172, 65% men) who underwent CAS with CTA of the supra-aortic vessels performed within prior 6 months. Standard descriptors of the density histogram were derived by open-source software automated analysis obtained by CTA plaque segmentation. Multiple logistic regression analysis, receiver operating characteristic (ROC) curve analysis and the area under the ROC (AUC) were used to identify potential prognostic variables and to assess the model performance for predicting unfavorable outcome (periprocedural death or myocardial infarction and any ipsilateral acute neurological event). Unfavorable outcome occurred in 17/172 (10%) patients (median age, 79 years; 12/17, 70% men). Kurtosis was an independent predictor of unfavorable outcome (odds ratio, 0.79; confidence interval, 0.65-0.97; p = 0.029). The predictive model for unfavorable outcome including CTA textural features outperformed the model without textural features (AUC 0.789 vs. 0.695, p = 0.004). In patients with stenotic carotid plaque, kurtosis derived by CTA density histogram analysis is an independent predictor of unfavorable outcome after CAS.

Risk factors for new ischemic cerebral lesions after carotid artery stenting: A systematic review and meta-analysis

BACKGROUND

New ischemic cerebral lesions (NICL) are commonly occur after carotid artery stenting (CAS) with an incidence rate ranging from 18-58% and are detected by diffusion-weighted imaging-magnetic resonance imaging (DWI-MRI). Numerous studies have reported that NICL could increase the risk of future cerebrovascular events and cognitive impairment. This systematic review and meta-analysis aimed to identify risk factors for NICL after CAS.

METHODS

Relevant literature reporting risk factors for NICL after CAS were searched. Randomized controlled trials, case-control studies, or cohort studies were included in accordance with the pre-specified eligibility criteria. The risk of bias was assessed using the Cochrane Collaboration criteria and the quality of evidence was assessed with the corresponding scale. Data were analyzed using the RevMan V. 5.3 analysis software.

RESULTS

The final analyses included a total of 21 studies and 1907 participants, including 764 NICL-positives and 1143 NICL-negatives. Determinants for NICL-positivity were age (mean deviation (MD): 2.60; 95% confidence interval (CI): [1.53-3.68]), symptomatic carotid lesions (odds ratio (OR): 1.77; 95% CI: [1.39-2.25]) and smoking (OR: 0.74; 95% CI: [0.58-0.94]). For symptomatic patients, risk factors for NICL-positive included diabetes mellitus (OR: 1.76; 95% CI: [1.09-2.82]), but smoking (OR: 0.54; 95% CI: [0.31-0.93]) was a protective factor. Risk factors for centers with high NICL incidence were age (MD: 2.05; 95% CI: [0.93-3.17]) and symptomatic carotid lesions (OR: 1.77; 95% CI: [1.29-2.45]).

CONCLUSIONS

Older age and symptomatic carotid lesions are associated with an increased risk of post-CAS NICL whereas smoking is associated with a decreased risk. Risk factors for NICL in symptomatic patients is diabetes mellitus, while those for patients at centers with high incidence are age and symptomatic carotid lesions. Systematic review registration: CRD42019121129.

Circumferential degree of carotid calcification is associated with new ischemic brain lesions after carotid artery stenting

Background

The relationship between plaque calcification and new ischemic brain lesions after carotid artery stenting (CAS) remains controversial. The purpose of this study was to determine if the circumferential degree of carotid calcification is associated with new ischemic brain lesions on diffusion-weighted imaging (DWI) after CAS.

Methods

A total of 96 patients with carotid stenosis of ≥50% who underwent CAS were enrolled in the study. All patients underwent preoperative carotid computed tomography (CT), and preoperative and postoperative brain MRI. The brain MRI sequences included T1WI, T2WI, T2-fluid-attenuated inversion recovery (FLAIR), and DWI. The location, circumferential degree, volume, percentage volume, maximum density, mean density, Agatston score of carotid calcification, and total plaque volume were assessed and compared between patients with and without new ischemic brain lesions after CAS. Univariate and multivariate analyses were performed to evaluate predictors of new ischemic brain lesions.

Results

All of the 96 patients (67.8±6.8 years of age, 83.3% men) were included in the analysis. New ischemic brain lesions on DWI were observed in 40 patients (41.7%). Patients with new ischemic brain lesions after CAS had a larger circumferential degree of calcification than those without new ischemic brain lesions (P<0.001). There was only a possible trend toward significance for the percentage volume of calcification between the two groups with and without new brain ischemic lesions (P=0.07). No significant differences were found regarding the location (P=0.18), volume (P=0.37), maximum density (P=0.44), mean density (P=0.39), Agatston score (P=0.28), and total plaque volume (P=0.33) of carotid calcification between the DWI+ and DWI- groups. In the multivariate analysis, an increased risk of new ischemic brain lesions was observed in patients with a high score for the circumferential degree of calcification [score 3; odds ratio (OR): 10.7, P<0.001; score 4, OR: 11.7, P=0.038].

Conclusions

The circumferential degree of carotid calcification was associated with new ischemic brain lesions after CAS. CAS should be avoided if possible for carotid stenosis with large circumferential calcified plaques.

Ultrasound-Based Carotid Plaque Characteristics Help Predict New Cerebral Ischemic Lesions after Endarterectomy

The aim of this study was to identify the ultrasound-based carotid plaque characteristics associated with new cerebral ischemic lesions after carotid endarterectomy (CEA). Between January 2013 and December 2018, carotid duplex ultrasound was performed in 1061 patients who underwent CEA. Brain magnetic resonance diffusion-weighted imaging (DWI) was performed pre-operatively and within 30 d after CEA. New cerebral ischemic lesions on DWI were observed in 169 patients. The cutoff value gray-scale median (GSM) used to distinguish DWI-positive from DWI-negative patients was 30.5, with an area under the receiver operating characteristic curve of 0.837. A larger proportion of multiple DWI lesions were observed in the GSM ≤30.5 group (59.5% vs. 41.5%, p = 0.030). Univariate and multivariate analyses identified GSM ≤30.5, ulcerated carotid plaques and pre-operative ischemic symptoms as predictors of post-operative cerebral DWI lesions. Our results indicate that ultrasound-based carotid plaque characteristics help predict new cerebral ischemic lesions after CEA.

Critical Appraisal on the Quality of Reporting on Safety and Efficacy of Transcarotid Artery Stenting With Flow Reversal

Transcarotid revascularization is an alternative to transfemoral carotid artery stenting, designed to avoid aortic arch manipulation and concomitant periprocedural stroke. This article aims to perform a detailed analysis on the quality of the currently available evidence on safety and efficacy of transcarotid artery revascularization. Although current evidence is promising, independent randomized controlled studies comparing transcarotid artery revascularization with carotid endarterectomy in recently symptomatic patients are lacking and will be necessary to establish the true value of transcarotid artery revascularization in carotid artery revascularization.

Effects of Aspiration and Re-transfusion Technique with Carotid Artery Stenting

Objective

Embolic stroke is the most serious complication after carotid artery stenting (CAS). The incidence rate of embolic stroke is reduced by the use of embolic protection devices (EPDs); however, there is no consensus on which EPD is the most effective. The aspiration and re-transfusion technique (ART) with CAS under distal balloon protection was adopted at our center to reduce the incidence of embolic complications. This retrospective study investigated the effects of ART.

Methods

From November 2010, 243 consecutive patients treated by CAS under distal balloon protection were included. ART was performed on 202 patients (ART group) and the other 40 patients only received distal balloon protection (non-ART group). In ART, the blood from the aspiration catheter was continuously returned through a filter to the femoral vein. The amount of debris was assessed intermittently using a small blood sample and the rest was returned. We investigated the diffusion-weighted imaging (DWI)-positive rate and symptomatic ischemic stroke one day after CAS.

Results

Compared with the non-ART group, the incidence of DWI-positive lesions (22.7% vs 37.5%, P = 0.07) and frequency of symptomatic ischemic stroke (0.9% vs 5.0%, P = 0.12) were reduced in the ART group. The hemoglobin reduction rate was significantly reduced by ART (11.1% vs 14.9%, P <0.01). In the ART group, the frequency of multiple lesions (more than 5) and large lesions (more than 10 mm) was lower than that in the non-ART group (P <0.01, P = 0.14).

Conclusion

CAS under distal balloon protection with ART was effective at reducing the incidence of DWI-positive lesions and may be useful to reduce the incidence of symptomatic ischemic stroke.

Angioplasty and carotid artery stenting: clinical and morphological factors affecting long-term outcomes

Aim. To identify clinical and morphological factors affecting the longterm outcomes of endovascular angioplasty and carotid artery stenting.

Material and methods. The analysis included 198 patients after carotid artery stenting between 03.2014 and 05.2018. There were following inclusion criteria: (1) 50% of symptomatic or 70% of asymptomatic carotid artery stenosis of according to NASCET (North American Symptomatic Carotid Endarterectomy Trial) criteria; (2) follow-up for each patient for at least 1 year. Using the univariate and multivariate logistic regression, risk factors associated with adverse events were determined.

Results. The incidence of major adverse events during the 12-month follow-up was 9,6% (n=19), including 4 (2%) major and 6 (3%) minor strokes, 7 (3,5%) cases of transient ischemic attack; one (0,5%) patient had transient blindness and one (0,5%) died in the long-term follow-up period due to acute cerebrovascular accident in the target arterial territory. Also, 11 (5,6%) patients had restenosis >50% after 12-month follow-up. Multivariate analysis showed that long-term outcomes were significantly affected by: age >70 years (odds ratio (OR)=1,27, 95% confidence interval (CI): 1,07-1,61 (p=0,01); using of open-cell stents (OR=1,02, 95% CI: 1,01-1,03 (p=0,034)); contralateral stenosis (OR=1,28, 95% CI: 1,05-1,57 (p=0,01); lesion length >15 mm (OR=1,46, 95% CI: 1,12-1,89 (p=0,01)); residual stenosis <30% (OR=1,38, 95% CI: 1,09-1,49 (p=0,012)); complicated atherosclerotic plaque (OR=1,78, 95% CI: 1,21- 2,34 (p=0,007)). The development of in-stent restenosis was significantly influenced by factors such as the residual stenosis ><30% (OR=1,26, 95% CI: 1,1-1,65; p=0,017) and severe plaque calcification (OR=1,24, 95% CI: 1,04-1,31; p=0,02). Conclusion. The results obtained indicate the need for more careful preparation for endovascular intervention. Such factors as the use of open-cell stents, contralateral stenosis, lesion length >< 30% (OR=1,38, 95% CI: 1,09-1,49 (p=0,012)); complicated atherosclerotic plaque (OR=1,78, 95% CI: 1,21- 2,34 (p=0,007)). The development of in-stent restenosis was significantly influenced by factors such as the residual stenosis <30% (OR=1,26, 95% CI: 1,1-1,65; p=0,017) and severe plaque calcification (OR=1,24, 95% CI: 1,04-1,31; p=0,02).

Conclusion. The results obtained indicate the need for more careful preparation for endovascular intervention. Such factors as the use of open-cell stents, contralateral stenosis, lesion length >15 mm, and residual stenosis < 30% may be associated with an increased risk of adverse events.

Perioperative Stroke

PURPOSE OF REVIEW

This review overviews perioperative stroke as it pertains to specific surgical procedures.

RECENT FINDINGS

As awareness of perioperative stroke increases, so does the opportunity to potentially improve outcomes for these patients by early stroke recognition and intervention. Perioperative stroke is defined to be any stroke that occurs within 30 days of the initial surgical procedure. The incidence of perioperative stroke varies and is dependent on the specific type of surgery performed. This chapter overviews the risks, mechanisms, and acute evaluation and management of perioperative stroke in four surgical populations: cardiac surgery, carotid endarterectomy, neurosurgery, and non-cardiac/non-carotid/non-neurological surgeries.

Patient risk factors associated with embolic stroke volumes after revascularization

OBJECTIVE

Previous research has shown that subclinical, microembolic infarcts result in long-term cognitive changes. Whereas both carotid endarterectomy (CEA) and carotid artery stenting (CAS) have potential for microembolic events, CAS has been shown to have a larger volume of infarct. We have previously shown that large-volume infarction is associated with long-term memory deterioration. The purpose of this study was to identify independent risk factors that trend toward higher embolic volumes in both procedures.

METHODS

A total of 162 patients who underwent carotid revascularization procedures were prospectively recruited at two separate institutions. Preoperative and postoperative brain magnetic resonance images were compared to identify procedure-related microinfarcts. A novel semiautomated approach was used to define volumes of infarcts for each patient. Patient-related factors including comorbidities, symptomatic status, and medications were analyzed. Tweedie regression analysis was used to identify risk factors associated with procedure-related infarct volume. Variables with an unadjusted P value of ≤ .05 were included in the multivariate analysis.

RESULTS

There were 80 CAS and 82 CEA procedures performed and analyzed for the data set; 81% of CAS patients had procedure-related new infarcts with a mean volume of 388.15 ± 927.90 mm³ compared with 30% of CEA patients with a mean volume of 74.80 ± 225.52 mm³. In the CAS cohort, increasing age (adjusted coefficient ± standard error, 0.06 ± 0.02; P < .01) and obesity (1.14 ± 0.35; P < .01) were positively correlated with infarct volume, whereas antiplatelet use (-1.11 ± 0.33; P < .001) was negatively correlated with infarct volume. For the CEA group, diabetes (adjusted coefficient ± standard error, 1.69 ± 0.65; P < .01) was identified as the only risk factor positively correlated with infarct volume, whereas increasing age (-0.10 ± 0.05; P = .03) was negatively correlated with infarct volume.

CONCLUSIONS

Risk factors for CAS- or CEA-related infarct volumes are identified in our study. Although the result warrants further validation, this study showed that advanced age, obesity, and diabetes independently predicted volume of microinfarcts related to CAS and CEA. These data provide valuable information for patient factor-based risk stratification and preoperative consultation for each procedure.

Recent Intraplaque Hemorrhage Is Associated with a Higher Risk of Ipsilateral Cerebral Embolism During Carotid Artery Stenting

OBJECTIVE

The purpose of this study was to identify which stage of intraplaque hemorrhage (IPH) is an independent risk factor for ipsilateral new ischemic lesions (NILs) after carotid artery stenting (CAS).

METHODS

In 268 patients treated with CAS, the association between postoperative ipsilateral NILs on diffusion-weighted imaging (DWI) and patient demographics, intraoperative factors, and plaque characteristics on multicontrast atherosclerosis characterization sequence was retrospectively analyzed.

RESULTS

A total of 268 patients were enrolled in the study. Ipsilateral NILs on DWI were detected in 32.8% of patients. Univariate analysis showed that the stage of IPH (along with lipid-rich necrotic core [LRNC]) (P < 0.001) in the carotid plaque, predilation (P = 0.012), stent type (P = 0.002), and aortic arch ulcer (P = 0.009) were associated with postoperative ipsilateral NILs, whereas other patient-related factors (P >0.05), type of embolic protection device (P = 0.072), postdilation (P = 0.388), calcification (P = 0.140), and LRNC (without IPH) (P = 0.086) were not. Multivariate logistic regression analysis showed that the acute and recent IPH (along with LRNC) (odds ratio [OR], 3.78, P = 0.011 and OR, 16.73, P < 0.001, respectively), aortic arch ulcer (OR, 2.46; P = 0.006), predilation (OR, 4.78; P = 0.015), and open cell stent (OR, 4.19; P < 0.001) were significantly associated with postoperative ipsilateral NILs on DWI.

CONCLUSIONS

Screening for recent IPH in carotid plaques using multicontrast atherosclerosis characterization sequence may identify plaques at a higher risk for cerebral embolism during CAS.

Risk factors for new ischaemic cerebral lesions after carotid artery stenting: protocol for a systematic review and meta-analysis

INTRODUCTION

New ischaemic cerebral lesions (NICL) detected by diffusion-weighted imaging MRI are common after carotid artery stenting (CAS), with an occurrence rate ranging from 18% to 57%. Many studies reported occurrence of NICL could increase risk of future cerebrovascular events and cognitive impairment. However, controversies about determinants for occurrence of NICL after CAS exist among studies, and one risk factor embodied in an article may not be in another. Aim of this study is to introduce a protocol for a systematic review and meta-analysis to identify risk factors associated with occurrence of NICL after CAS.

METHODS AND ANALYSIS

All relevant literature referring to risk factors for occurrence of NICL after CAS will be searched on the major databases, such as PubMed, Embase, Web of Science and the Cochrane Library until 31 December 2018. Literature, which must be randomised controlled trials, case-control studies or cohort studies, will be included in accordance with the prespecified eligibility criteria. The risk of bias will be assessed using the Cochrane Collaboration criteria and the quality of evidence will be assessed with the corresponding scale. Data will be extracted with a form prepared before and analysed using RevMan V.5.3 analyses software. Heterogeneity will be assessed using I² statistic. Our systematic review will be performed according to the guidance from the Cochrane Handbook for Systematic Reviews of Interventions and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.

ETHICS AND DISSEMINATION

There is no need for ethical approval because primary data will not be attained. The systematic review will be presented at international conferences and published in peer-reviewed journals.

PROSPERO REGISTRATION NUMBER

CRD42019121129.