Assessment of Carotid Plaque Stability Using Contrast-Enhanced Ultrasound and Its Correlation With the Expression of CD147 and MMP-9 in the Plaque

Diagnostic accuracy of carotid plaque instability by noninvasive imaging: a systematic review and meta-analysis

AIMS

There is increasing evidence that plaque instability in the extracranial carotid artery may lead to an increased stroke risk independently of the degree of stenosis. We aimed to determine diagnostic accuracy of vulnerable and stable plaque using noninvasive imaging modalities when compared to histology in patients with symptomatic and asymptomatic carotid atherosclerosis.

METHODS AND RESULTS

Medline Ovid, Embase, Cochrane Library, and Web of Science were searched for diagnostic accuracy of noninvasive imaging modalities (CT, MRI, US) in the detection of 1) vulnerable/stable plaque, and 2) vulnerable/stable plaque characteristics, compared to histology. The quality of included studies was assessed by QUADAS-2 and univariate and bivariate random-effect meta-analyses were performed. We included 36 vulnerable and 5 stable plaque studies in the meta-analysis, and out of 211 plaque characteristics from remaining studies, we classified 169 as vulnerable and 42 as stable characteristics (28 CT, 120 MRI, 104 US characteristics). We found that MRI had high accuracy [90% (95% CI: 82-95%)] in the detection of vulnerable plaque, similar to CT [86% (95% CI: 76-92%); P > 0.05], whereas US showed less accuracy [80% (95% CI: 75-84%); P = 0.013]. CT showed high diagnostic accuracy in visualizing characteristics of vulnerable or stable plaques (89% and 90%) similar to MRI (86% and 89%; P > 0.05); however, US had lower accuracy (77%, P < 0.001 and 82%, P > 0.05).

CONCLUSION

CT and MRI have a similar, high performance in detecting vulnerable carotid plaques, whereas US showed significantly less diagnostic accuracy. Moreover, MRI visualized all vulnerable plaque characteristics allowing for a better stroke risk assessment.

REGISTRATION

PROSPERO ID CRD42022329690.

Integrating genomic profiling to clinical data: assessing the impact of CD147 expression on plaque stability

Background

Acute Coronary Syndrome (ACS) continues to be a leading cause of death and illness worldwide. Differentiating stable from unstable coronary plaques is essential for enhancing patient outcomes. This research investigates the role of CD147 as a biomarker for plaque stability among coronary artery disease patients.

Methods

The study began with high-throughput sequencing of blood samples from six patients, divided equally between those with Stable Angina (SA) and Unstable Angina (UA), followed by bioinformatics analysis. Expanding upon these findings, the study included 31 SA patients and 30 patients with ACS, using flow cytometry to examine CD147 expression on platelets and monocytes. Additionally, logistic regression was utilized to integrate traditional risk factors and evaluate the predictive value of CD147 expression for plaque stability.

Results

Initial sequencing displayed a notable difference in CD147 expression between SA and UA groups, with a significant increase in UA patients. Further analysis confirmed that elevated platelet CD147 expression was strongly associated with unstable plaques (OR = 277.81, P < .001), after adjusting for conventional risk factors, whereas monocyte CD147 levels did not show a significant difference.

Conclusion

Elevated CD147 expression on platelets is a crucial biomarker for identifying unstable coronary artery plaques, offering insights into patient risk stratification and the development of targeted treatment strategies. This underscores the pivotal role of molecular research in understanding and managing coronary artery disease, paving the way for improved clinical outcomes.

Novel imaging modalities for the identification of vulnerable plaques

Atherosclerosis is a slow, progressive disease that is closely associated with major adverse cardiovascular events. Early diagnosis and risk assessment of atherosclerosis can effectively improve the prognosis and reduce the occurrence of adverse cardiovascular events in the later stage. A variety of invasive and non-invasive imaging modalities are important tools for diagnosing lesions, monitoring the efficacy of treatments, and predicting associated risk events. This review mainly introduces the four commonly used non-invasive imaging modalities in clinical practice and intravascular imaging such as optical coherence tomography, intravascular ultrasound imaging, and near-infrared spectroscopy, compares the advantages and disadvantages in the diagnosis of vulnerable plaques, and briefly summarizes the new progressions of each.

Comparison of the diagnostic performance of contrast-enhanced ultrasound and high-resolution magnetic resonance imaging in the evaluation of histologically defined vulnerable carotid plaque: a systematic review and meta-analysis

Background

Vulnerable carotid plaque is closely associated with ischemic stroke. Contrast-enhanced ultrasound (CEUS) and high-resolution magnetic resonance imaging (HR-MRI) are two imaging modalities capable of assessing the vulnerability of carotid plaques. This systematic review aimed to compare the diagnostic performance of CEUS and HR-MRI in the evaluation of histologically defined vulnerable carotid plaques.

Methods

A systematic literature search with predefined search terms was performed on PubMed, the Cochrane library, Embase, and Web of Science from January 2001 to December 2023. Studies that evaluated the diagnostic accuracy of vulnerable carotid plaques confirmed by histology with CEUS and/or HR-MRI were included. The pooled values were calculated using a random-effects meta-analysis to determine diagnostic power.

Results

This analysis included a total of 839 patients from 20 studies comprising 1,357 HR-MRI plaques and CEUS 504 plaques. With the reference to histological results, all nine CEUS studies focused on the detection of intraplaque neovascularization (IPN), and three studies also examined morphological changes or ulcerated plaques; meanwhile, among the HR-MRI studies, seven predominantly focused on identifying intraplaque hemorrhage (IPH) and three mainly examined lipid-rich necrotic cores (LRNCs). The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and the area under the curve (AUC) for CEUS studies were 0.85 [95% confidence interval (CI): 0.81-0.89], 0.76 (95% CI: 0.69-0.83), 3.41 (95% CI: 1.68-6.94), 0.14 (95% CI: 0.05-0.38), 27.68 (95% CI: 5.78-132.62), and 0.89 [standard error (SE) 0.06], respectively; for HR-MRI, these values were 0.88 (95% CI: 0.85-0.90), 0.89 (95% CI: 0.86-0.92), 7.49 (95% CI: 3.28-17.09), 0.17 (95% CI: 0.12-0.24), 49.13 (95% CI: 23.87-101.11), and 0.94 (SE 0.01), respectively. The difference in AUC between the two modalities was not statistically significant (Z=0.82; P=0.68).

Conclusions

CEUS and HR-MRI are valuable noninvasive diagnostic tools for identifying histologically confirmed vulnerable carotid plaques and demonstrate similar diagnostic performance. CEUS is more capable of detecting IPN and morphological changes, while HR-MRI is more suited to classifying IPH and LRNCs.

Utility of ultrasound in the perioperative phase of carotid endarterectomy and carotid artery stent implantation

BACKGROUND

This article reviews the latest research results of the use of ultrasound technology in the perioperative period of carotid endarterectomy and carotid stenting and discusses the role of ultrasound technology in accurately evaluating carotid stenosis and plaque stability, assisting in selecting the most suitable surgical method, and providing optimal perioperative imaging to guide carotid endarterectomy (CEA) and carotid artery stenting (CAS) to reduce the occurrence and progression of stroke.

METHODS

The research published in recent years on the application of ultrasound in the perioperative period of CEA and CAS was reviewed through the databases of CNKI, Pubmed, and Web of Science.

RESULTS

Ultrasound has high clinical value in preoperative screening for indications, assessing the degree of carotid artery stenosis and the nature of plaque; monitoring hemodynamic changes intraoperatively to prevent cerebral ischemia or overperfusion; and evaluating surgical outcomes postoperatively and in late follow-up review.

CONCLUSION

Ultrasound is currently widely used perioperatively in CEA and CAS and has even become the preferred choice of clinicians to evaluate the efficacy of surgery and follow-up. The presence of vulnerable plaque is an important risk factor for ischemic stroke. Contrast-enhanced ultrasound is an excellent tool to assess plaque stability. In most studies, ultrasound has been used only in a short follow-up period after CEA and CAS, and data from longer follow-ups are needed to provide more reliable evidence.

Comparison of ultrasonic shear wave elastography, AngioPLUS planewave ultrasensitive imaging, and optimized high-resolution magnetic resonance imaging in evaluating carotid plaque stability

Objective

This study aimed to compare the efficiency of evaluating carotid plaque stability using ultrasonic shear wave elastography (SWE), AngioPLUS planewave ultrasensitive imaging (AP), and optimized high-resolution magnetic resonance imaging (MRI).

Methods

A total of 100 patients who underwent carotid endarterectomy at our hospital from October 2019 to August 2022 were enrolled. Based on the final clinical diagnosis, these patients were divided into vulnerable (n = 62) and stable (n = 38) plaque groups. All patients were examined using ultrasound SWE, AP, and optimized high-resolution MRI before surgery. The clinical data and ultrasound characteristics of patients of the two groups were compared. Considering the final clinical diagnosis as the gold standard, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of SWE, AP, high-resolution MRI, and the final clinical diagnosis of vulnerable plaque were calculated. Pearson's correlation test was used to analyze the correlations of AP, SWE, and MRI results with the grading results of carotid artery stenosis.

Results

Statistically significant differences were noticed in terms of the history of smoking and coronary heart disease, plaque thickness, surface rules, calcified nodules, low echo area, and the degree of carotid artery stenosis between the two groups (P < 0.05). Considering the final clinical diagnosis as the gold standard, the sensitivity, specificity, PPV, and NPV of SWE-based detection of carotid artery vulnerability were 87.10% (54/62), 76.32% (29/38), 85.71% (54/63) and 78.38% (29/37), respectively, showing a general consistency with the final clinical results (Kappa = 0.637, P < 0.05). Considering the final clinical diagnosis as the gold standard, the sensitivity, specificity, PPV and NPV of AP-based detection of carotid artery vulnerability were 93.55% (58/62), 84.21% (32/38), 90.63% (58/64), and 88.89% (32/36), respectively, which agreed with the final clinical detection results (Kappa = 0.786, P < 0.05). Considering the final clinical diagnosis as the gold standard, the sensitivity, specificity, PPV and NPV of high-resolution MRI-based detection of carotid artery vulnerability were 88.71% (55/62), 78.95% (30/38), 87.30% (55/63), and 81.08% (30/37), respectively, showing consistency with the final clinical results (Kappa = 0.680, P < 0.05). AP, SWE, and MRI results were positively correlated with the results of carotid artery stenosis grading (P < 0.05).

Conclusion

AP technology is a non-invasive, inexpensive, and highly sensitive method to evaluate the stability of carotid artery plaques. This method can dynamically display the flow of blood in new vessels of plaque in real time and provide a reference for clinical diagnosis and treatment.

Effect of evolocumab on the progression of intraplaque neovascularization of the carotid based on contrast-enhanced ultrasonography (EPIC study): A prospective single-arm, open-label study

Background and Purpose: The aim of this study was to explore the effect of half a year of evolocumab plus moderate-intensity statin treatment on carotid intraplaque neovascularization (IPN) and blood lipid levels. Methods: A total of 31 patients with 33 carotid plaques who received evolocumab plus statin treatment were included. Blood lipid levels, B-mode ultrasound and contrast-enhanced ultrasonography (CEUS) at baseline and after half a year of evolocumab plus statin therapy were collected. The area under the curve (AUC) reflected the total amount of acoustic developer entering the plaque or lumen within the 180 s measurement period. The enhanced intensity reflected the peak blood flow intensity during the monitoring period, and the contrast agent area reflected the area of vessels in the plaques. Results: Except for high-density lipoprotein cholesterol (HDL-c), all other lipid indices decreased. Compared with baseline, low-density lipoprotein cholesterol (LDL-c) decreased by approximately 57% (p < 0.001); total cholesterol (TC) decreased by approximately 34% (p < 0.001); small dense low-density lipoprotein (sd-LDL) decreased by approximately 52% (p < 0.001); and HDL-c increased by approximately 20% (p < 0.001). B-mode ultrasonography showed that the length and thickness of the plaque and the hypoechoic area ratio were reduced (p < 0.05). The plaque area, calcified area ratio, and lumen cross-sectional area changed little (p > 0.05). CEUS revealed that the area under the curve of plaque/lumen [AUC (P/L)] decreased from 0.27 ± 0.13 to 0.19 ± 0.11 (p < 0.001). The enhanced intensity ratio of plaque/lumen [intensity ratio (P/L)] decreased from 0.37 ± 0.16 to 0.31 ± 0.14 (p = 0.009). The contrast agent area in plaque/area of plaque decreased from 19.20 ± 13.23 to 12.66 ± 9.59 (p = 0.003). The neovascularization score decreased from 2.64 ± 0.54 to 2.06 ± 0.86 (p < 0.001). Subgroup analysis based on statin duration (<6 months and ≥6 months) showed that there was no significant difference in the AUC (P/L) or intensity ratio (P/L) at baseline or after half a year of evolocumab treatment. Conclusion: This study found that evolocumab combined with moderate-intensity statins significantly improved the blood lipid profile and reduced carotid IPN. Clinical Trial Registration: https://www.clinicaltrials.gov; identifier: NCT04423406.