Intravascular ultrasound as a clinical adjunct for carotid plaque characterization

Intravascular ultrasonography assisted carotid artery stenting for treatment of carotid stenosis: Two case reports

BACKGROUND

Digital subtraction angiography (DSA), the gold standard of cerebrovascular disease diagnosis, is limited in its diagnostic ability to evaluate arterial diameter. Intravascular ultrasonography (IVUS) has advantages in assessing stenosis and plaque nature and improves the evaluation and effectiveness of carotid artery stenting (CAS).

CASE SUMMARY

Case 1: A 65-year-old man presented with a five-year history of bilateral lower limb weakness due to stroke. Physical examination showed decreased strength (5-/5) in both lower limbs. Carotid artery ultrasound, magnetic resonance angiography, and computed tomography angiography (CTA) showed a right proximal internal carotid artery (ICA) stenosis (70%-99%), acute cerebral infarction, and severe right ICA stenosis, respectively. We performed IVUS-assisted CAS to measure the stenosis and detected a low-risk plaque at the site of stenosis prior to stent implantation. Post-stent balloon dilatation was performed and postoperative IVUS demonstrated successful expansion and adherence. CTA six months postoperatively showed no significant increase in in-stent stenosis. Case 2: A 36-year-old man was admitted with a right common carotid artery (CCA) dissection detected by ultrasound. Physical examination showed no positive neurological signs. Carotid ultrasound and CTA showed lumen dilation in the proximal CCA with an intima-like structure and bulging in the proximal segment of the right CCA with strip-like low-density shadow (dissection or carotid web). IVUS-assisted DSA confirmed right CCA dissection. CAS was performed and intraoperative IVUS suggested a large residual false lumen. Post-stent balloon dilatation was performed reducing the false lumen. DSA three months postoperatively indicated good stent expansion with mild stenosis.

CONCLUSION

IVUS aids decision-making during CAS by accurately assessing carotid artery wall lesions and plaque nature preoperatively, dissection and stenosis morphology intraoperatively, and visualizing and confirming CAS postoperatively.

Interplay between Artificial Intelligence and Biomechanics Modeling in the Cardiovascular Disease Prediction

Cardiovascular disease (CVD) is the most common cause of morbidity and mortality worldwide, and early accurate diagnosis is the key point for improving and optimizing the prognosis of CVD. Recent progress in artificial intelligence (AI), especially machine learning (ML) technology, makes it possible to predict CVD. In this review, we first briefly introduced the overview development of artificial intelligence. Then we summarized some ML applications in cardiovascular diseases, including ML-based models to directly predict CVD based on risk factors or medical imaging findings and the ML-based hemodynamics with vascular geometries, equations, and methods for indirect assessment of CVD. We also discussed case studies where ML could be used as the surrogate for computational fluid dynamics in data-driven models and physics-driven models. ML models could be a surrogate for computational fluid dynamics, accelerate the process of disease prediction, and reduce manual intervention. Lastly, we briefly summarized the research difficulties and prospected the future development of AI technology in cardiovascular diseases.

A Parametric Study of Flushing Conditions for Improvement of Angioscopy Visibility

During an angioscopy operation, a transparent liquid called dextran is sprayed out from a catheter to flush the blood away from the space between the camera and target. Medical doctors usually inject dextran at a constant flow rate. However, they often cannot obtain clear angioscopy visibility because the flushing out of the blood is insufficient. Good flushing conditions producing clear angioscopy visibility will increase the rate of success of angioscopy operations. This study aimed to determine a way to improve the clarity for angioscopy under different values for the parameters of the injection waveform, endoscope position, and catheter angle. We also determined the effect of a stepwise waveform for injecting the dextran only during systole while synchronizing the waveform to the cardiac cycle. To evaluate the visibility of the blood-vessel walls, we performed a computational fluid dynamics (CFD) simulation and calculated the visible area ratio (VAR), representing the ratio of the visible wall area to the total area of the wall at each point in time. Additionally, the normalized integration of the VAR called the area ratio (ARVAR) represents the ratio of the visible wall area as a function of the dextran injection period. The results demonstrate that the ARVAR with a stepped waveform, bottom endoscope, and three-degree-angle catheter results in the highest visibility, around 25 times larger than that under the control conditions: a constant waveform, a center endoscope, and 0 degrees. This set of conditions can improve angioscopy visibility.

Clinical Utility of Intravascular Ultrasound (IVUS) in Carotid Artery Interventions: A Systematic Review and Meta-analysis

BACKGROUND

Carotid plaque morphology plays an important role in determining outcome of carotid artery stenting (CAS). Intravascular ultrasound (IVUS) and its extension VH (Virtual Histology)-IVUS evaluate plaque characteristics in real time and guide decision making during stenting. To date, there is no consensus about indications of IVUS and its validated methods. This systematic review and meta-analysis aims to evaluate the clinical utility of IVUS in carotid artery interventions (CAS) and develop a future consensus for research and practice parameters.

METHODS

A systematic review and meta-analysis was performed of the English literature articles published till February 2021. Studies reporting on IVUS parameters and findings and also its performance compared with other imaging modalities were included in review. Pooled prevalence with 95% confidence intervals (CI) was calculated. The statistical analysis was conducted in R version 3.6.2.

RESULTS

A total of 2015 patients from 29 studies were included. Proportional meta-analysis was performed on 1566 patients from 11 studies. In 9 studies, stroke/transient ischemic attack (TIA) had a pooled prevalence of 4% (95% CI 3%-5%) while asymptomatic stroke had a pooled prevalence of 46% (95% CI 31%-62%) in 4 studies following IVUS. Two studies reported that IVUS detected more plaque protrusion compared with angiography (n=33/396 vs 11/396). IVUS led to stent type or size change in 8 of 48 cases which were missed on angiography in 3 other studies. Concordance between VH-IVUS and true histology was good at 80% to 85% reported in 2 studies.

CONCLUSIONS

This systematic review and meta-analysis showed, though IVUS fared better to computed tomography (CT)/magnetic resonance (MR) angiography for better stent selection during CAS, with low to moderate risk of bias in the studies included. However, large scale, preferably randomized controlled studies are needed to predict its role in determining clinical outcome.

Is it possible to prevent cerebral embolization by improving the design and technology of carotid stent implantation?

INTRODUCTION

The prevention of atherosclerotic plaque fragmentation during carotid artery stenting is a fundamental problem in decreasing the risk of disability of patients. The goal of this review is to clarify whether the stent design can have a decisive impact on the rate of intraoperative and postoperative complications.

AREAS COVERED

Different designs of the carotid stents are briefed and the advantages and disadvantages of different stent designs are discussed as well as the results of their clinical use. Various solutions are presented to reduce cerebral embolism during carotid artery stenting.

EXPERT OPINION

There is no conclusive evidence for the benefits of closed cell and hybrid stents. The stent design cannot completely resolve the problem of cerebral embolism. Most of the events of cerebral microembolism occur at the stages of stent delivery rather than protrusion of an atherosclerotic plaque in the long-term follow-up. Most likely, minimization of the risks for periprocedural and postprocedural strokes requires not only the new solutions in stent design as well as the corresponding delivery systems and brain embolic protection systems, but also the new strategies of preprocedural drug stabilization of the atherosclerotic plaque in the carotid artery. Abbreviations: CAS, carotid artery stenting; CE, carotid endarterectomy; DW-MRI, diffusion-weighted magnetic resonance imaging; ECA, external carotid artery; ICA, internal carotid artery; IVUS, intravascular ultrasound examination; OCT, optical coherence tomography.

Intravascular ultrasound-guided internal carotid artery stenting

AIM

The study was aimed at demonstrating efficacy and feasibility of intravascular ultrasound during internal carotid artery stenting for assessment of atheromatous plaque protrusion through a stent.

PATIENTS AND METHODS

Over the period from October to December 2018, the specialists of our Centre performed a total of 90 internal carotid artery stenting procedures in 83 patients (of these, 7 patients underwent bilateral staged stenting of both internal carotid arteries) using intravascular ultrasound in order to assess intraoperative protrusion of an atherosclerotic plaque through the implanted stent. The patients' age varied from 42 to 87 (mean 68.6±6.9) years. Symptomatic lesions of internal carotid arteries were revealed in 14 (16.9%) operated patients and asymptomatic lesions in 69 (83.1%). The degree of stenosis varied from 60% to 90% according to the findings of preliminary duplex ultrasonography and was subsequently confirmed by the results of multislice computed tomography or selective angiography. The assessment of the patients' neurological status, as well as duplex ultrasonography of brachiocephalic arteries were performed at a scheduled follow-up visit on day 30 after discharge from hospital.

RESULTS

The technical success of stenting was achieved in 100% of patients. According to the findings of intravascular ultrasound, plaque protrusion was observed in eight (8.8%) stented patients. Among them, six (6.6%) were free from angiographic signs of protrusion and only two (2.2%) had apparent angiographic signs of protrusion. During the early postoperative period, transient ischaemic attack was identified in four (4.4%) cases. One (1.1%) patient was found to develop ST-segment elevation acute myocardial infarction 24 hours after internal carotid artery stenting, followed by large hemispheric stroke on the side of stenting revealed on postoperative day 3. Nine (10%) patients according to the findings of intravascular ultrasound were diagnosed as having incomplete stent apposition after postdilatation, with the absence of such signs on angiography.

CONCLUSION

Intravascular ultrasound during carotid stenting provides a more accurate assessment of such an event as atherosclerotic plaque protrusion through a stent's cells. At the same time, IVUS-guided assessment of the intraoperative outcome may prevent the risk for the development of stroke in the early postoperative period. Besides, intravascular ultrasound allows a more detailed assessment of stent apposition and the degree of stent expansion in order to optimize and improve the remote results of the operation.

Risk factors associated with microembolization after carotid intervention

BACKGROUND

Microembolization after carotid artery stenting (CAS) and carotid endarterectomy (CEA) has been documented and may confer risk for neurocognitive impairment. Patients undergoing stenting are known to be at higher risk for microembolization. In this prospective cohort study, we compare the microembolization rates for patients undergoing CAS and CEA and perioperative characteristics that may be associated with microembolization.

METHODS

Patients undergoing CAS and CEA were prospectively recruited under local institutional review board approval from an academic medical center. All patients also received 3T brain magnetic resonance imaging with a diffusion-weighted imaging sequence preoperatively and within 24 hours postoperatively to identify procedure-related new embolic lesions. Preoperative, postoperative, procedural factors, and plaque characteristics were collected. Factors were tested for statistical significance with logistic regression.

RESULTS

A total of 202 patients were enrolled in the study. There were 107 patients who underwent CAS and 95 underwent CEA. Patients undergoing CAS were more likely to have microemboli than patients undergoing CEA (78% vs 27%; P < .0001). For patients undergoing CAS, patency of the external carotid artery (odds ratio [OR], 11.4; 95% confidence interval [CI], 1.11-117.6; P = .04), lesion calcification (OR, 5.68; 95% CI, 1.12-28.79; P = .04), and lesion length (OR, 0.29; 95% CI, 0.08-1.01; P = .05) were all found to be independent risk factors for perioperative embolization. These factors did not confer increased risk to patients undergoing CEA.

CONCLUSIONS

Patients undergoing CAS are at higher risk for perioperative embolization. The risk for perioperative embolization is related to the length of the lesion and calcification. Identifying the preoperative risk factors may help to guide patient selection and, thereby, reduce embolization-related neurocognitive impairment.

Silent brain infarcts on diffusion-weighted imaging after carotid revascularisation: A surrogate outcome measure for procedural stroke? A systematic review and meta-analysis

Aim

To investigate whether lesions on diffusion-weighted imaging (DWI+) after carotid artery stenting (CAS) or endarterectomy (CEA) might provide a surrogate outcome measure for procedural stroke.

Materials and Methods

Systematic MedLine® database search with selection of all studies published up to the end of 2016 in which DWI scans were obtained before and within seven days after CAS or CEA. The correlation between the underlying log odds of stroke and of DWI+ across all treatment groups (i.e. CAS or CEA groups) from included studies was estimated using a bivariate random effects logistic regression model. Relative risks of DWI+ and stroke in studies comparing CAS vs. CEA were estimated using fixed-effect Mantel-Haenszel models.

Results

We included data of 4871 CAS and 2099 CEA procedures (85 studies). Across all treatment groups (CAS and CEA), the log odds for DWI+ was significantly associated with the log odds for clinically manifest stroke (correlation coefficient 0.61 (95% CI 0.27 to 0.87), p = 0.0012). Across all carotid artery stenting groups, the correlation coefficient was 0.19 (p = 0.074). There were too few CEA groups to reliably estimate a correlation coefficient in this subset alone. In 19 studies comparing CAS vs. CEA, the relative risks (95% confidence intervals) of DWI+ and stroke were 3.83 (3.17-4.63, p < 0.00001) and 2.38 (1.44-3.94, p = 0.0007), respectively.

Discussion

This systematic meta-analysis demonstrates a correlation between the occurrence of silent brain infarcts on diffusion-weighted imaging and the risk of clinically manifest stroke in carotid revascularisation procedures.

Conclusion

Our findings strengthen the evidence base for the use of DWI as a surrogate outcome measure for procedural stroke in carotid revascularisation procedures. Further randomised studies comparing treatment effects on DWI lesions and clinical stroke are needed to fully establish surrogacy.

Diagnostic imaging in the management of patients with metabolic syndrome

Metabolic syndrome (MetS) is the constellation of metabolic risk factors that might foster development of type 2 diabetes and cardiovascular disease. Abdominal obesity and insulin resistance play a prominent role among all metabolic traits of MetS. Because intervention including weight loss can reduce these morbidity and mortality in MetS, early detection of the severity and complications of MetS could be useful. Recent advances in imaging modalities have provided significant insight into the development and progression of abdominal obesity and insulin resistance, as well as target organ injuries. The purpose of this review is to summarize advances in diagnostic imaging modalities in MetS that can be applied for evaluating each components and target organs. This may help in early detection, monitoring target organ injury, and in turn developing novel therapeutic target to alleviate and avert them.

Physiologic levels of resistin induce a shift from proliferation to apoptosis in macrophage and VSMC co-culture

BACKGROUND

Resistin, an adipokine with inflammatory properties, has been associated with plaque vulnerability. Vascular smooth muscle cells and macrophages are the major cellular components in advanced atherosclerotic plaques and interdependently affect plaque stability. The purpose of this study was to examine the effects of resistin on the interactions of vascular smooth muscle cells and macrophages using co-culture systems.

METHODS

Human monocytes were differentiated into macrophages. Vascular smooth muscle cells were grown and starved prior to co-culture condition. Indirect co-culture was performed by treating macrophages with resistin at 10 ng/mL for 24 hours with/without εV1-2, a selective protein kinase C epsilon inhibitor. Macrophages supernatants were then used to treat vascular smooth muscle cells for 24 hours. Direct co-culture was performed by culturing macrophages and vascular smooth muscle cells together for 24 to 48 hours. Cultures were evaluated for changes in proliferation, apoptosis, and gene expression of apoptosis, proliferation, and inflammation-associated genes.

RESULTS

Macrophages induced vascular smooth muscle cells proliferation, which was further exaggerated in resistin-treated macrophages in the indirect co-culture model. Resistin also upregulated cyclin D1 and proliferating cell nuclear antigen via protein kinase C epsilon in the indirect co-culture. Augmented proliferation was further confirmed in the direct co-culture model, particularly at increased macrophage ratios. However, resistin treatment induced apoptosis in the presence of direct cell to cell interactions. Along with the shift to apoptosis, expressions of caspase 3 and caspase 8 were upregulated. The expression of kappa-light-chain-enhancer of activated B cells 1 and 2 was similar in direct and indirect co-cultures.

CONCLUSION

Resistin promotes a shift from proliferation to apoptosis in vascular smooth muscle cells and macrophage co-culture systems with cellular composition similar to that found in vulnerable regions of plaques. Protein kinase C epsilon mediates the effects of resistin, suggesting that protein kinase C epsilon may represent a therapeutic strategy in resistin-associated atherosclerotic complications.

Carotid Artery Wall Imaging: Perspective and Guidelines from the ASNR Vessel Wall Imaging Study Group and Expert Consensus Recommendations of the American Society of Neuroradiology

Identification of carotid artery atherosclerosis is conventionally based on measurements of luminal stenosis and surface irregularities using in vivo imaging techniques including sonography, CT and MR angiography, and digital subtraction angiography. However, histopathologic studies demonstrate considerable differences between plaques with identical degrees of stenosis and indicate that certain plaque features are associated with increased risk for ischemic events. The ability to look beyond the lumen using highly developed vessel wall imaging methods to identify plaque vulnerable to disruption has prompted an active debate as to whether a paradigm shift is needed to move away from relying on measurements of luminal stenosis for gauging the risk of ischemic injury. Further evaluation in randomized clinical trials will help to better define the exact role of plaque imaging in clinical decision-making. However, current carotid vessel wall imaging techniques can be informative. The goal of this article is to present the perspective of the ASNR Vessel Wall Imaging Study Group as it relates to the current status of arterial wall imaging in carotid artery disease.

Imaging of high-risk carotid plaques: ultrasound

Duplex ultrasonography has a well-established role in the assessment of the degree of stenosis caused by carotid atherosclerosis. This assessment is derived from Doppler velocity changes induced by the narrowing lumen of the artery. New research into the mechanisms for plaque rupture and atheroembolic stroke indicates that the degree of narrowing is an imperfect predictor of stroke risk, and that other factors, such as plaque composition and remodeling and biomechanical forces acting on the plaque, can play a role. New advances in ultrasound imaging technology have made it possible to investigate these measures of plaque vulnerability to identify pre-embolic unstable carotid plaques. Efforts have been made to quantify the morphologic appearance of the plaque in B-mode images and to correlate them with histology. Additional research has resulted in the first generation of clinically available 3-dimensional ultrasound transducers that reduce operator-dependence and variability. Finally, ultrasonography provides real-time imaging and physiologic information that can be utilized to measure disruptive forces acting on carotid plaques. We review some of these exciting developments in ultrasonography and discuss how these may impact clinical practice.

Pretreatment with and ongoing use of omega-3 fatty acid ethyl esters reduce the slow-flow phenomenon and prevent in-stent restenosis in patients undergoing carotid artery stenting

OBJECTIVE

Carotid artery stenting (CAS) is a less invasive alternative to carotid endarterectomy, but it is essential to prevent thromboembolic complications during CAS and to suppress in-stent restenosis (ISR) after CAS because of the relatively high risk of periprocedural and follow-up stroke events. Clinical trials have demonstrated the strong relationship of carotid plaque vulnerability with the subsequent risk of ipsilateral ischemic stroke and thromboembolic complications during CAS. Recent studies demonstrated that both low eicosapentaenoic acid (EPA) and low docosahexaenoic acid (DHA) levels were significantly associated with lipid-rich coronary and carotid plaques, but little is known about the effect of administration of omega-3 fatty acids (O-3FAs) containing EPA and DHA before and after CAS for stabilizing carotid plaque, preventing thromboembolic complications, and suppressing ISR. In this study, the efficacy of pretreatment with and ongoing daily use of O-3FA in addition to statin treatment was evaluated in patients undergoing CAS.

METHODS

This study was a nonrandomized prospective trial with retrospective analysis of historical control data. From 2012 to 2015, there were 100 consecutive patients with hyperlipidemia undergoing CAS for carotid artery stenosis who were divided into two groups. Between 2012 and 2013 (control period), 47 patients were treated with standard statin therapy. Between 2014 and 2015 (O-3FA period), patients were treated with statin therapy and add-on oral O-3FA ethyl esters containing 750 mg/d DHA and 1860 mg/d EPA from 4 weeks before CAS, followed by ongoing daily use for at least 12 months. In all patients, the plaque morphology by virtual histology intravascular ultrasound, the incidence of new ipsilateral ischemic lesions on the day after CAS, the slow-flow phenomenon during CAS, and ISR within 12 months after CAS were compared between the periods.

RESULTS

The slow-flow phenomenon during CAS with filter-type embolic protection devices decreased in the O-3FA period (1 of 53 patients [2%]) compared with the control period (7 of 47 patients [15%]; P = .02). Furthermore, ISR for 12 months after CAS was significantly decreased in the O-3FA period (1 of 53 patients [2%]) compared with the control period (10 of 47 patients [21%]; P = .01). On virtual histology intravascular ultrasound analysis, the fibrofatty area was significantly smaller and the fibrous area was significantly greater in the O-3FA period. On multivariate logistic regression analysis, a low EPA/arachidonic acid ratio and a symptomatic lesion were the factors related to vulnerable plaque (P = .01 [odds ratio, 5.24; 95% confidence interval, 1.65-16.63] and P = .01 [odds ratio, 11.72; 95% confidence interval, 2.93-46.86], respectively).

CONCLUSIONS

Pretreatment with O-3FA reduces the slow-flow phenomenon generated by plaque vulnerability during CAS, and on-going daily use of O-3FA suppresses ISR after CAS.

A Review on Carotid Ultrasound Atherosclerotic Tissue Characterization and Stroke Risk Stratification in Machine Learning Framework

Cardiovascular diseases (including stroke and heart attack) are identified as the leading cause of death in today's world. However, very little is understood about the arterial mechanics of plaque buildup, arterial fibrous cap rupture, and the role of abnormalities of the vasa vasorum. Recently, ultrasonic echogenicity characteristics and morphological characterization of carotid plaque types have been shown to have clinical utility in classification of stroke risks. Furthermore, this characterization supports aggressive and intensive medical therapy as well as procedures, including endarterectomy and stenting. This is the first state-of-the-art review to provide a comprehensive understanding of the field of ultrasonic vascular morphology tissue characterization. This paper presents fundamental and advanced ultrasonic tissue characterization and feature extraction methods for analyzing plaque. Additionally, the paper shows how the risk stratification is achieved using machine learning paradigms. More advanced methods need to be developed which can segment the carotid artery walls into multiple regions such as the bulb region and areas both proximal and distal to the bulb. Furthermore, multimodality imaging is needed for validation of such advanced methods for stroke and cardiovascular risk stratification.

Effect of Intravascular Ultrasound-assisted Thoracic Endovascular Aortic Repair for "Complicated" Type B Aortic Dissection

Background:

Intravascular ultrasound (IVUS) examination can provide useful information during endovascular stent graft repair. However, its actual clinical utility in thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (type B-AD) remains unclear, especially in complicated aortic dissection. We evaluated the effect of IVUS as a complementary tool during TEVAR.

Methods:

From September 2011 to April 2012, we conducted a prospective cohort study of 47 consecutive patients with “complicated” type B-AD diagnosed. We divided the patients into two groups: IVUS-assisted TEVAR group and TEVAR using angiography alone group. The general procedure of TEVAR was performed. We evaluated the perioperative and follow-up events. Patient demographics, comorbidities, preoperative images, dissection morphology, details of operative strategy, intraoperative events, and postoperative course were recorded.

Results:

A total of 47 patients receiving TEVAR were enrolled. Among them (females, 8.51%; mean age, 57.38 ± 13.02 years), 13 cases (27.66%) were selected in the IVUS-assisted TEVAR group, and 34 were selected in the TEVAR group. All patients were symptomatic. The average diameter values of IVUS measurements in the landing zone were greater than those estimated by computed tomography angiography (31.82 ± 4.21 mm vs. 30.64 ± 4.13 mm, P < 0.001). The technique success rate was 100%. Among the postoperative outcomes, statistical differences were only observed between the IVUS-assisted TEVAR group and TEVAR group for total operative time and the amount of contrast used (P = 0.013 and P < 0.001, respectively). The follow-up ranged from 15 to 36 months for the IVUS-assisted TEVAR group and from 10 to 35 months for the TEVAR group (P = 0.646). The primary endpoints were no statistical difference in the two groups.

Conclusions:

Intraoperative IVUS-assisted TEVAR is clinically feasible and safe. For the endovascular repair of “complicated” type B-AD, IVUS may be helpful for understanding dissection morphology and decrease the operative time and the amount of contrast used.

Utilization of Intravascular Ultrasound during Carotid Artery Stenting

For patients at high risk for surgery, carotid artery stenting (CAS) is a viable alternative to help reduce risk of stroke for patients with high-grade carotid artery stenosis; however, a higher incidence of perioperative stroke has been observed in patients undergoing stenting compared to those undergoing open surgery. Intravascular ultrasound (IVUS) is commonly used during coronary artery procedures to help evaluate lesions and to guide stent placement. Multiple groups have sought to determine whether IVUS could also be used during CAS. While IVUS has been shown to be both feasible and safe during CAS, there is limited evidence that demonstrates direct improvement in procedural outcomes. Further studies focusing on clinical outcomes should be conducted in order to justify routine use of this technology during CAS.

Therapeutic effect of carotid artery stenting versus endarterectomy for patients with high-risk carotid stenosis

OBJECTIVE

To investigate therapeutic effect of carotid artery stenting versus endarterectomy for patients with high-risk carotid stenosis.

METHODS

A total of 130 carotid stenosis patients at high-risk of stroke were randomly divided into stenting group and endarterectomy group, including 65 patients in each group. The patients in the endarterectomy group underwent endarterectomy and those in the stenting group received carotid artery stenting for treatment.

RESULTS

After operation, carotid intima-media thickness (IMT), plague areas and carotid artery resistance indexes in both groups decreased significantly, and the carotid artery peak blood flow velocities increased significantly and had significant differences with that before operation (P < 0.05). After operation, total cholesterol (TC), triglyceride (TG) and low density lipoprotein (LDL) values in two groups all significantly decreased, and intragroup and intergroup differences were statistically significant (P < 0.05). Postoperative three months of followed-up found that the mortality rate in stenting group was 1.5% and that in the endarterectomy group was 9.2%; the mortality rate in the stenting group was significantly lower than the endarterectomy group (P < 0.05).

CONCLUSION

Compared with carotid endarterectomy, application of carotid artery stenting can effectively promote patency of blood flow in the carotid artery, and exertion of its effect is related to lowering lipid and lowering inflammatory factor expression.