Rapid improvement in carotid adventitial angiogenesis and plaque neovascularization after rosuvastatin therapy in statin treatment-naïve subjects

Non-Invasive Assessment of Vascular Damage Through Pulse Wave Velocity and Superb Microvascular Imaging in Pre-Dialysis Patients

Background/Objectives: Cardiovascular disease is the main cause of morbidity and mortality in Chronic Kidney Disease (CKD), so it is of great importance to find simple and non-invasive tools to detect vascular damage in pre-dialysis CKD patients. This study aimed to assess the applicability of non-invasive techniques to evaluate vascular damage in stages CKD-2 to CKD-5 and its progression after an 18-month follow-up using (A) carotid-femoral pulse wave velocity (PWV) to assess aortic stiffness and (B) Superb Microvascular Imaging (SMI) ultrasound to assess adventitial neovascularization compared with other traditional techniques to evaluate vascular damage, such as carotid intima-media thickness and Kauppila index. Methods: The study involved 43 CKD patients in stages CKD-2 to CKD-5 and a group of 38 sex- and age-matched controls, studied at baseline and at an 18-month follow-up. Age, sex, body mass index, arterial pressure, pharmacological treatments, and blood and urinary parameters were collected. Aortic stiffness was determined by carotid-femoral PWV and abdominal aortic calcification was assessed in lateral lumbar X-rays and quantified by the Kauppila index. Carotid intima-media thickness (cIMT), the number of carotid plaques, and adventitial neovascularization were evaluated by SMI. Results: Vascular impairment was mostly detected in CKD-4 and CKD-5 stages, with increased aortic stiffness measured by PWV and increased carotid plaques and adventitial neovascularization measured by SMI ultrasound. Furthermore, CKD-5 patients showed greater abdominal aortic calcification. Interestingly, CKD patients displayed a negative correlation between serum soluble Klotho (sKlotho) and cIMT. Finally, CKD patients showed no progression of vascular impairment after the 18-month follow-up, with the exception of carotid plaques. Conclusions: Performing non-invasive PWV and SMI ultrasound might be useful to evaluate vascular damage in CKD before entering dialysis, possibly helping to prevent cardiovascular events, although future studies should clarify the use of these techniques in clinical practice.

Incremental clinical value of intraplaque neovascularization in predicting recurrent ischemic stroke

OBJECTIVE

Carotid intraplaque neovascularization (IPN) detected by contrast-enhanced ultrasound (CEUS) is a risk factor for recurrent ischemic stroke. However, it is still unclear whether IPN can be used to accurately identify patients with recurrent ischemic stroke in clinical practice. Herein, we investigated the clinical predictive value of IPN for recurrent ischemic stroke in a real-world setting.

METHODS

We enrolled 200 patients with ischemic stroke and atherosclerotic carotid stenosis who were followed up for 2 years. The endpoint was recurrent ischemic stroke. Cox regression and subgroup analyses were employed to assess whether treatment affected the relationship between IPN and recurrent ischemic stroke. The net classification index (NRI) and integrated discriminant improvement index (IDI) were used to validate the additional clinical value of IPN in identifying recurrent ischemic stroke.

RESULTS

During the 2-year follow-up, 36 patients experienced recurrent ischemic stroke. Cox regression analyses showed that IPN (grade 2), hypoechoic plaque, high homocysteine levels, and smoking were independent risk factors for recurrent ischemic stroke. Additional IPN evaluation may increase the NRI (0.512; 95% confidence interval [CI]: 0.083-0.624) and IDI (0.151; 95% CI: 0.010-0.213) for identifying high-risk patients with recurrent ischemic stroke. In addition, in the subgroup undergoing revascularization, the proportion of IPN (grade 2) was significantly higher in patients with recurrent ischemic stroke than in patients with nonrecurrent ischemic stroke (p = 0.001).

INTERPRETATION

In clinical settings, IPN, assessed by CEUS, may provide additional clinical value for predicting recurrent ischemic stroke, helping to identify patients with ischemic stroke who require close follow-up.

Pharmacological interventions for intraplaque neovascularization in atherosclerosis

Advanced atherosclerosis is linked to plaque instability, which can result in rupture and the onset of a heart attack. Evidence gathered from human atheroma plaques indicates that intraplaque neovascularization poses a risk to plaque stability and may lead to plaque hemorrhage. Hence, targeting the neovascularization within the atheroma plaque has the potential to mitigate the plaque's vulnerability. While neovascularization has been extensively explored in the context of cancer, research on pharmacological inhibition of this phenomenon in atherosclerosis remains limited. This systematic review aimed to comprehensively assess current and emerging pharmacological interventions for inhibiting intraplaque neovascularization in preclinical settings. Electronic databases (Web of Science, PubMed, Scopus, and Ovid) were searched from January 2013 until February 1, 2024. Preclinical studies reporting the effect of any pharmacological interventions targeting intraplaque neovascularization were included. A total of 10 articles involving in vivo animal studies were eligible for inclusion, with five of them incorporating in vitro experiments to complement their in vivo findings. The pharmacological interventions studied were axitinib, ghrelin, K5, rosuvastatin, atorvastatin, 3PO, everolimus, melatonin, Si-Miao-Yong-A, and protocatechuic aldehyde. All the interventions showed a positive impact in inhibiting intraplaque neovascularization in various atherosclerotic animal models through various signaling pathways. This review provides valuable insights into pharmacological approaches to attenuate intraplaque neovascularization that could serve as a promising therapeutic avenue to enhance plaque stability.

Effect of pharmacologic anti-atherosclerotic therapy on carotid intraplaque neovascularization: A systematic review

Intraplaque neovascularization (IPN), a key feature of vulnerable carotid plaque, is associated with adverse cardiovascular (CV) events. Statin therapy has been shown to diminish and stabilize atherosclerotic plaque, but its effect on IPN is uncertain. This review investigated the effects of common pharmacologic anti-atherosclerotic therapies on carotid IPN. Electronic databases (MEDLINE, EMBASE and Cochrane Library) were searched from inception until July 13, 2022. Studies evaluating the effect of anti-atherosclerotic therapy on carotid IPN among adults with carotid atherosclerosis were included. Sixteen studies were eligible for inclusion. Contrast-enhanced ultrasound (CEUS) was the most common IPN assessment modality (n=8), followed by dynamic contrast-enhanced MRI (DCE-MRI) (n=4), excised plaque histology (n=3) and superb microvascular imaging (n=2). In fifteen studies, statins were the therapy of interest and one study assessed PCSK9 inhibitors. Among CEUS studies, baseline statin use was associated with a lower frequency of carotid IPN (median OR = 0.45). Prospective studies showed regression of IPN after 6-12 months of lipid-lowering therapy, with more regression observed in treated participants compared to untreated controls. Our findings suggest that lipid-lowering therapy with statins or PCSK9 inhibitors is associated with IPN regression. However, there was no correlation between change in IPN parameters and change in serum lipids and inflammatory markers in statin-treated participants, so it is unclear whether these factors are mediators in the observed IPN changes. Lastly, this review was limited by study heterogeneity and small sample sizes, so larger trials are needed to validate findings.

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.

Clinical translation of quantitative magnetic resonance imaging biomarkers - An overview and gap analysis of current practice

PURPOSE

This overview of the current landscape of quantitative magnetic resonance imaging biomarkers (qMR IBs) aims to support the standardisation of academic IBs to assist their translation to clinical practice.

METHODS

We used three complementary approaches to investigate qMR IB use and quality management practices within the UK: 1) a literature search of qMR and quality management terms during 2011-2015 and 2016-2020; 2) a database search for clinical research studies using qMR IBs during 2016-2020; and 3) a survey to ascertain the current availability and quality management practices for clinical MRI scanners and associated equipment at research institutions across the UK.

RESULTS

The analysis showed increased use of all qMR methods between the periods 2011-2015 and 2016-2020 and diffusion-tensor MRI and volumetry to be popular methods. However, the "translation ratio" of journal articles to clinical research studies was higher for qMR methods that have evidence of clinical translation via a commercial route, such as fat fraction and T2 mapping. The number of journal articles citing quality management terms doubled between the periods 2011-2015 and 2016-2020; although, its proportion relative to all journal articles only increased by 3.0%. The survey suggested that quality assurance (QA) and quality control (QC) of data acquisition procedures are under-reported in the literature and that QA/QC of acquired data/data analysis are under-developed and lack consistency between institutions.

CONCLUSIONS

We summarise current attempts to standardise and translate qMR IBs, and conclude by outlining the ideal quality management practices and providing a gap analysis between current practice and a metrological standard.

Assessment of Therapeutic Response to Statin Therapy in Patients With Intracranial or Extracranial Carotid Atherosclerosis by Vessel Wall MRI: A Systematic Review and Updated Meta-Analysis

Background and Aims: Statin therapy is an essential component of cardiovascular preventive care. In recent years, various vessel wall MRI (VW-MRI) techniques have been used to monitor atherosclerosis progression or regression in patients with extracranial or intracranial large-artery atherosclerosis. We aimed to perform a systematic review and meta-analysis on the effects of statin therapy on plaque evolution as assessed by VW-MRI.

Materials and Methods: Prospective studies investigating carotid and intracranial atherosclerotic plaques in patients on statin therapy monitored by serial VW-MRI were systematically identified in the literature. The plaque burden and lipid-rich necrotic core (LRNC) volume of carotid plaque and the imaging features of intracranial plaques were extracted and summarized. For studies investigating carotid artery wall volume and LRNC volume, combined estimates were derived by meta-analysis.

Results: The study identified 21 studies of carotid plaque and two studies of intracranial plaque. While 16 studies investigating carotid plaques that included 780 patients by High-resolution VW-MRI were included in the meta-analysis. There was no significant change in carotid wall volume from baseline to 12 months. A significant change in LRNC volume was observed at > 12 months compared with baseline (Effect = −10.69, 95% CI = −19.11, −2.28, P < 0.01), while no significant change in LRNC volume at 3–6 months or 7–12 months after statin therapy initiation in 6 studies. Increases in fibrous tissue and calcium and reduction in neovascularization density of the plaque were seen in 2/3 studies (including 48/59 patients), 1/3 studies (including 17/54 patients), and 2/2 studies (including 71 patients) after statin therapy, respectively. Two studies with 257 patients in intracranial atherosclerosis showed that statins could effectively decrease wall volume and plaque enhancement volume.

Conclusions: Collective data indicated that statins could potentially stabilize carotid plaques by significantly reducing LRNC with 1 year of therapy as shown on serial carotid VW-MRI. There was no significant decrease in wall volume, which nonetheless indicated that plaque composition changes might be more sensitive to response monitoring than wall volume. It is likely that more sensitive, clinically relevant, and preferably quantitative indicators of therapeutic effects on intracranial vessel plaque morphology will be developed in the future.

Quantitative Magnetic Resonance Imaging Assessment of the Relationships Between Fat Fraction and R2* Inside Carotid Plaques, and Circulating Lipoproteins

BACKGROUND

Lipid-rich necrotic core (LRNC) and intraplaque hemorrhage (IPH) are morphological features of high-risk atherosclerotic plaques. However, their relationship to circulating lipoproteins is unclear.

PURPOSE

To study associations between changes in lipoproteins vs. changes in LRNC (represented by fat fraction [FF]) and IPH (represented by R2*).

STUDY TYPE

Prospective.

SUBJECTS

Fifty-two patients with carotid plaques, 33 males (63.5%), mean age 72 (±5).

FIELD STRENGTH/SEQUENCE

Four-point fast gradient Dixon magnetic resonance imaging (MRI) was used to quantify FF and R2* (to measure IPH) inside plaques and in vessel wall. Turbo-spin echo was used for T₁ weighted sequences to guide manual segmentation.

ASSESSMENT

Carotid MRI and serum lipid levels were assessed at baseline and at 1-year follow-up. For patients, lipid-lowering therapy was customized to reduce low-density lipoprotein (LDL) levels below 1.8 mmol/L. Segmentation was performed with one set of regions of interest for the plaque and one for the vessel wall at the location of the plaque. Thereby MRI data for FF, R2*, and volumes in plaque- and vessel-wall segmentations could be obtained from baseline and follow-up, as well as changes over the study year.

STATISTICAL TESTS

Pearson correlation coefficient for correlations. Paired samples t-test for changes over time. Significance at P < 0.05, 95% confidence interval.

RESULTS

LDL decreased significantly (2.19-1.88 mmol/L, Z - 2.9), without correlation to changes in plaque composition, nor to the significant reduction in vessel-wall volume (-106.3 mm³ ). Plaque composition remained unchanged, FF +8.5% (P = 0.366) and R2* +3.5% (P = 0.304). Compared to plaque segmentations, R2* was significantly lower in the vessel-wall segmentations both at baseline (-9.3%) and at follow-up (-9.1%).

DATA CONCLUSION

The absence of correlations between changes in lipoproteins and changes in plaque composition indicates more complex relationships between these parameters than previously anticipated. The significant differences in both R2* and volume dynamics comparing plaque segmentations and vessel-wall segmentations suggest differences in their pathobiology of atherosclerosis.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY: Stage 4.

Roadmap Consensus on Carotid Artery Plaque Imaging and Impact on Therapy Strategies and Guidelines: An International, Multispecialty, Expert Review and Position Statement

Current guidelines for primary and secondary prevention of stroke in patients with carotid atherosclerosis are based on the quantification of the degree of stenosis and symptom status. Recent publications have demonstrated that plaque morphology and composition, independent of the degree of stenosis, are important in the risk stratification of carotid atherosclerotic disease. This finding raises the question as to whether current guidelines are adequate or if they should be updated with new evidence, including imaging for plaque phenotyping, risk stratification, and clinical decision-making in addition to the degree of stenosis. To further this discussion, this roadmap consensus article defines the limits of luminal imaging and highlights the current evidence supporting the role of plaque imaging. Furthermore, we identify gaps in current knowledge and suggest steps to generate high-quality evidence, to add relevant information to guidelines currently based on the quantification of stenosis.

Clinical Efficacy and Safety of Angiogenesis Inhibitors: Sex Differences and Current Challenges

Vasoactive molecules, such as vascular endothelial growth factor (VEGF) and endothelins, share cytokine-like activities and regulate endothelial cell (EC) growth, migration and inflammation. Some endothelial mediators and their receptors are targets for currently approved angiogenesis inhibitors, drugs that are either monoclonal antibodies raised towards VEGF, or inhibitors of vascular receptor protein kinases and signaling pathways. Pharmacological interference with the protective functions of ECs results in a similar spectrum of adverse effects. Clinically, the most common side effects of VEGF signaling pathway inhibition include an increase in arterial pressure, left ventricular (LV) dysfunction ultimately causing heart failure, and thromboembolic events, including pulmonary embolism, stroke, and myocardial infarction. Sex steroids such as androgens, progestins, and estrogen and their receptors (ERα, ERβ, GPER; PR-A, PR-B; AR) have been identified as important modifiers of angiogenesis, and sex differences have been reported for anti-angiogenic drugs. This review article discusses the current challenges clinicians are facing with regard to angiogenesis inhibitor treatments, including the need to consider sex differences affecting clinical efficacy and safety. We also propose areas for future research taking into account the role of sex hormone receptors and sex chromosomes. Development of new sex-specific drugs with improved target and cell-type selectivity likely will open the way personalized medicine in men and women requiring antiangiogenic therapy and result in reduced adverse effects and improved therapeutic efficacy.

Cholesterol, carotid artery disease and stroke: what the vascular specialist needs to know

Hypercholesterolemia is a risk factor for carotid artery stenosis and stroke. Statins are the main drugs for the management of hypercholesterolemia and they are strongly recommended by international guidelines for the management of vascular patients. The present review will focus on the associations between cholesterol, carotid artery stenosis and stroke and will cover several topics, including the conservative and perioperative/periprocedural management of carotid patients, the effect of statins on contrast-induced nephropathy developing after endovascular carotid interventions, the role of statin loading prior to endovascular procedures, as well as the indirect beneficial effects of statin treatment on renal function. It will also discuss the topics of statin intolerance and alternative cholesterol-lowering options for statin-intolerant vascular patients. Cholesterol levels play a prognostic role in carotid patients with regards to both short- and long-term stroke and mortality rates. Physicians should keep in mind the pivotal role of cholesterol levels in determining cardiovascular outcomes and the pleiotropic beneficial effects associated with statin use and should not miss the opportunity for cardiovascular risk reduction with aggressive statin treatment.