A systematic literature review of the effect of carotid atherosclerosis on local vessel stiffness and elasticity

Efficacy of acupuncture in patients with carotid atherosclerosis: a randomized controlled clinical trial

BACKGROUND

The current clinical management of carotid atherosclerosis is based on the control of risk factors and medicine. However, the risk of adverse events associated with the medicine resulting in concerns and low medication compliance makes it necessary to seek a safer alternative therapy. This study assessed the effectiveness and safety of acupuncture as a treatment for carotid atherosclerosis.

METHODS

In this randomized controlled trial, patients with carotid atherosclerotic plaques were included and randomly assigned (1:1) to receive real acupuncture or sham acupuncture for 12 weeks. The follow-up period was 12 weeks. The primary outcome included carotid intima-media thickness (cIMT), plaque score (PS), plaque volume (PV) and grey-scale median (GSM). Secondary outcome was pulse wave velocity (PWV). Adverse events results were recorded as safety outcomes.

RESULTS

From January 2021 to February 2022, 60 eligible patients were included. 55 patients (91.7%) completed the intervention and the 12-week follow-up and there was no statistical difference in demographics between the groups. At the end of treatment, the real acupuncture group had significantly reduced PS (P = 0.002), PV (P = 0.000), and improved GSM (P = 0.044). There was no significant difference in the reduction in cIMT (Left cIMT: P = 0.338, Right cIMT: P = 0.204) and PWV between the groups (the left BS: P = 0.429; the left ES: P = 0.701; the right BS: P = 0.211; the right ES: P = 0.083). Three mild adverse reactions occurred during the study.

CONCLUSION

This study found that acupuncture had a certain effect on reducing the thickness and volume of carotid plaque and improving the stability of plaque with minor side effects. These findings suggest that acupuncture may be a potential alternative therapy for carotid atherosclerosis.

TRIAL REGISTRATION

This trial has been registered at ClinicalTrials.gov (ChiCTR2100041762). Submitted 30 December 2020, Registered 4 January 2021 Prospectively registered.

Integrating Computational and Biological Hemodynamic Approaches to Improve Modeling of Atherosclerotic Arteries

Atherosclerosis is the primary cause of cardiovascular disease, resulting in mortality, elevated healthcare costs, diminished productivity, and reduced quality of life for individuals and their communities. This is exacerbated by the limited understanding of its underlying causes and limitations in current therapeutic interventions, highlighting the need for sophisticated models of atherosclerosis. This review critically evaluates the computational and biological models of atherosclerosis, focusing on the study of hemodynamics in atherosclerotic coronary arteries. Computational models account for the geometrical complexities and hemodynamics of the blood vessels and stenoses, but they fail to capture the complex biological processes involved in atherosclerosis. Different in vitro and in vivo biological models can capture aspects of the biological complexity of healthy and stenosed vessels, but rarely mimic the human anatomy and physiological hemodynamics, and require significantly more time, cost, and resources. Therefore, emerging strategies are examined that integrate computational and biological models, and the potential of advances in imaging, biofabrication, and machine learning is explored in developing more effective models of atherosclerosis.

Carotid artery stiffness and risk of vascular events and mortality: the REGICOR study

INTRODUCTION AND OBJECTIVES

The aims of this study were to determine the dose-response association of carotid arterial stiffness with vascular outcomes and overall mortality, and to assess their added predictive capacity.

METHODS

Population-based cohort study including 6468 individuals, with a median follow-up of 6.5 years. Six carotid artery stiffness indices were assessed: strain, stiffness, Peterson elasticity coefficient, compliance coefficient, distensibility coefficient, and pulse wave velocity (PWV). Incident coronary, cerebrovascular, global vascular, and total fatal events were identified.

RESULTS

Carotid compliance and distensibility coefficients were not associated with any of the outcomes. Carotid stiffness, Peterson elasticity coefficient, and PWV showed a direct linear relationship to cerebrovascular disease: the risk increased by 8% (95%CI, 1-16) per stiffness unit increase, by 7% (95%CI, 2-13) per 10-unit Peterson elasticity coefficient increase, and by 26% (95%CI, 8-48) per PWV unit increase. Carotid strain showed a nonlinear association with ischemic heart disease. When strain was ≤ 0.09 units, each 0.01-unit increase was associated with a 15% lower risk of coronary events (95%CI,-33 to 6); above 0.09 units, each 0.01 increase in strain was associated with a 16% higher risk of coronary events (95%CI, 6-27). The addition of the stiffness indices did not improve the predictive capacity of validated risk functions.

CONCLUSIONS

Carotid stiffness, Peterson elasticity coefficient, and PWV have a direct linear association with cerebrovascular disease risk. Carotid strain is not linearly related to U-shaped ischemic heart disease risk. The inclusion of these indexes does not improve the predictive capacity of risk functions.

The influence of epigenetics and inflammation on cardiometabolic risks

Cardiometabolic diseases include metabolic syndrome, obesity, type 2 diabetes mellitus, and hypertension. Epigenetic modifications participate in cardiometabolic diseases through several pathways, including inflammation, vascular dysfunction, and insulin resistance. Epigenetic modifications, which encompass alterations to gene expression without mutating the DNA sequence, have gained much attention in recent years, since they have been correlated with cardiometabolic diseases and may be targeted for therapeutic interventions. Epigenetic modifications are greatly influenced by environmental factors, such as diet, physical activity, cigarette smoking, and pollution. Some modifications are heritable, indicating that the biological expression of epigenetic alterations may be observed across generations. Moreover, many patients with cardiometabolic diseases present with chronic inflammation, which can be influenced by environmental and genetic factors. The inflammatory environment worsens the prognosis of cardiometabolic diseases and further induces epigenetic modifications, predisposing patients to the development of other metabolism-associated diseases and complications. A deeper understanding of inflammatory processes and epigenetic modifications in cardiometabolic diseases is necessary to improve our diagnostic capabilities, personalized medicine approaches, and the development of targeted therapeutic interventions. Further understanding may also assist in predicting disease outcomes, especially in children and young adults. This review describes epigenetic modifications and inflammatory processes underlying cardiometabolic diseases, and further discusses advances in the research field with a focus on specific points for interventional therapy.

PCSK9 inhibitors: current status and emerging frontiers in lipid control

INTRODUCTION

Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of global mortality, imposing substantial healthcare economic burdens. Among the modifiable risk factors, hypercholesterolemia, especially elevated low-density lipoprotein cholesterol (LDL-C), plays a pivotal role in ASCVD development. Novel therapies such as PCSK9 (Proprotein Convertase Subtilisin/Kexin type 9) inhibitors are emerging to address this concern. These inhibitors offer the potential to reduce ASCVD risk by directly targeting LDL-C levels.

AREAS COVERED

The article reviews the structural and functional aspects of PCSK9, highlighting its role in LDL receptor regulation. The pharmacological strategies for PCSK9 inhibition, including monoclonal antibodies, binding peptides, gene silencing, and active immunization, are explored. Clinical evidence from various trials underscores the safety and efficacy of PCSK9 inhibitors in reducing LDL-C levels and potentially improving cardiovascular outcomes. Despite these promising results, challenges such as cost-effectiveness and long-term safety considerations are addressed.

EXPERT OPINION

Among PCSK9 inhibitors, monoclonal antibodies represent a cornerstone. Many trials have showed their efficacy in reducing LDL-C and the risk for major adverse clinical events, revealing long-lasting effects, with special benefits particularly for statin-intolerant and familial hypercholesterolemia patients. However, long-term impacts, high costs, and patient selection necessitate further research.

Low-invasive neural recording in mouse models with diabetes via an ultrasmall needle-electrode

Diabetes is known to cause a variety of complications, having a high correlation with Alzheimer's disease. Electrophysiological recording using a microscale needle electrode is a promising technology for the study, however, diabetic brain tissue is more difficult to record neuronal activities than normal tissue due to these complications including the development of cerebrovascular disease. Here we show an electrophysiological methodology for diabetic db/db mice (+Leprdb/+Leprdb) using a 4-μm-tip diameter needle-electrode device. The needle electrode minimized the tissue injury when compared to a typical larger metal electrode, as confirmed by bleeding during penetration. The proposed electrode device showed both acute and chronic in vivo recording capabilities for diabetic mice while reducing the glial cells' responses. Because of these device characteristics, the 4-μm-tip diameter needle-electrode will allow electrophysiological studies on diabetes models of not only mice, as proven in this study, but also other animals.

Comparison of Parameters for Assessment of Carotid Stiffness and Their Association with Carotid Atherosclerosis in Rural Australian Adults: A Pilot Study

Carotid stiffness has been associated with the development and progression of carotid artery disease and is an independent factor for stroke and dementia. There has also been a lack of comparison of different ultrasound-derived carotid stiffness parameters and their association with carotid atherosclerosis. This pilot study aimed to investigate the associations between carotid stiffness parameters (derived via ultrasound echo tracking) and the presence of carotid plaques in Australian rural adults. In cross-sectional analyses, we assessed forty-six subjects (68 ± 9 years; mean ± SD) who underwent carotid ultrasound examinations. Carotid stiffness was assessed by a noninvasive echo-tracking method, measuring and comparing multiple carotid stiffness parameters, including stroke change in diameter (ΔD), stroke change in lumen area (ΔA), β- stiffness index, pulse wave velocity beta (PWV-β), compliance coefficient (CC), distensibility coefficient (DC), Young's elastic modulus (YEM), Peterson elastic modulus (Ep), and strain. Carotid atherosclerosis was assessed bilaterally by the presence of plaques in the common and internal carotid arteries, while carotid stiffness was assessed at the right common carotid artery. β-stiffness index, PWV-β, and Ep were significantly higher (p = 0.006, p = 0.004, p = 0.02, respectively), whilst ΔD, CC, DC, and strain were lower among subjects with carotid plaques (p = 0.036, p = 0.032, p = 0.01, p = 0.02, respectively) comparing to subjects without carotid plaques. YEM and ΔA did not significantly differ among the groups. Carotid plaques were associated with age, history of stroke, coronary artery disease, and previous coronary interventions. These results suggest that unilateral carotid stiffness is associated with the presence of carotid plaques.

Lateral M-Mode: Ultrasound Visualization of Displacement Along Longitudinal Direction at Intima-Media Complex

Quantification of the dynamics of the carotid artery wall is useful in evaluating arteriosclerosis and atherosclerosis. As the carotid artery wall moves not only in the radial direction but also in the longitudinal direction, longitudinal movement should be considered in the analysis of the dynamic properties of the carotid artery wall. In this study, we propose a "lateral M-mode" method for visualizing the longitudinal movement of the intima-media complex (IMC). For the lateral M-mode, we set the target line in the longitudinal direction along the IMC and visualize the signals on the target line frame-by-frame by correcting the position of the target line along the radial displacement estimated by the phased tracking method. Differentiating the envelope signals between consecutive ultrasound beams was effective in visualizing the lateral movement of the IMC. The precision of the longitudinal displacement of the IMC estimated using the conventional block-matching method was validated by comparing it with the lateral M-mode. Because the conventional M-mode sequence plays an important role in evaluation of the dynamics of various tissues, the proposed "lateral M-mode" contributes to a detailed understanding of vascular dynamics and the development of diagnostic methods for vascular diseases.

Fully automatic carotid arterial stiffness assessment from ultrasound videos based on machine learning

Arterial stiffness (AS) refers to the loss of arterial compliance and alterations in vessel wall properties. The study of local carotid stiffness (CS) is particularly important since carotid artery stiffening raises the risk of stroke, cognitive impairment, and dementia. So, stiffness measurement as a screening tool approach is crucial because it can reduce mortality and facilitate therapy planning. This study aims to evaluate the stiffness of the CCA using machine learning (ML) through the features of diameter change (ΔD) and stiffness parameters. This study was conducted in seven stages: data collection, preprocessing, CCA segmentation, CCA lumen diameter (DCCA) computing during cardiac cycles, denoising signals of DCCA, computational of AS parameters, and stiffness assessment using ML. The 51 videos (with 25 s) of CCA B-mode ultrasound (US) were used and analyzed. Each US video yielded approximately 750 sequential frames spanning about 24 cardiac cycles. Firstly, US preset settings with time gain compensation with a U-pattern were employed to enhance CCA segmentations. The study showed that auto region-growing, employed three times, is appropriate for segmenting walls with a short running time (4.56 s/frame). The diameter computed for frames constructs a signal (diameter signal) with noisy parts in the shape of peak variance and an un-smooth side. Among the 12 employed smoothing methods, spline fitting with a mean peak difference per cycle (MPDCY) of 0.58 pixels was the most effective for the diameter signal. The authors propose the MPDCY as a new selection criterion for smoothing methods with highly preserved peaks. The ΔD (D_sys-D_dia) determined in this study was validated by statistical analysis as a viable replacement for manual ΔD measurement. Statistical analysis was carried out by Mann-Whitney t-test with a p-value of 0.81, regression line R² = 0.907, and there was no difference in means between the two groups for box plots. The stiffness parameters of the carotid arteries were calculated based on auto-ΔD and pulse pressure. Five ML models, including K-nearest neighbor (KNN), support vector machine (SVM), decision tree (DT), logistic regression (LR), and random forest (RF), fed by distension (ΔD) and five stiffness parameters, were used to distinguish between the stiffened and un-stiffened CCA. Except for SVM, all models performed excellently in terms of specificity, sensitivity, precision, and area under the curve (AUC). In addition, the scatterplot and statistical analysis of the fed features confirm these remarkable outcomes. The scatter plot demonstrates that a linear hyperline can easily distinguish between the two classes. The statistical analysis shows that the stiffness parameters computed from the database of this work were statistically (p < 0.05) distributed into the non-stiffness and stiffness groups. The presented models are validated by applying them to additional datasets. Applying models to other datasets reveals a model performance of 100%. The proposed ML models could be applied in clinical practice to detect CS early, which is essential for preventing stroke.

Understanding Atherosclerosis Pathophysiology: Can Additive Manufacturing Be Helpful?

Atherosclerosis is one of the leading causes of death worldwide. Although this subject arouses much interest, there are limitations associated with the biomechanical investigation done in atherosclerotic tissues, namely the unstandardized tests for the mechanical characterization of these tissues and the inherent non-consensual results obtained. The variability of tests and typologies of samples hampers direct comparisons between results and hinders the complete understanding of the pathologic process involved in atherosclerosis development and progression. Therefore, a consensual and definitive evaluation of the mechanical properties of healthy and atherosclerotic blood vessels would allow the production of physical biomodels that could be used for surgeons' training and personalized surgical planning. Additive manufacturing (AM), commonly known as 3D printing, has attracted significant attention due to the potential to fabricate biomodels rapidly. However, the existing literature regarding 3D-printed atherosclerotic vascular models is still very limited. Consequently, this review intends to present the atherosclerosis disease and the consequences of this pathology, discuss the mechanical characterization of atherosclerotic vessels/plaques, and introduce AM as a potential strategy to increase the understanding of atherosclerosis treatment and pathophysiology.

Recent Update on the Development of PCSK9 Inhibitors for Hypercholesterolemia Treatment

The proprotein convertase subtilisin/kexin-type 9 (PCSK9) binds to low-density lipoprotein receptors (LDLR), thereby trafficking them to lysosomes upon endocytosis and enhancing intracellular degradation to prevent their recycling. As a result, the levels of circulating LDL cholesterol (LDL-C) increase, which is a prominent risk factor for developing atherosclerotic cardiovascular diseases (ASCVD). Thus, PCSK9 has become a promising therapeutic target that offers a fertile testing ground for new drug modalities to regulate plasma LDL-C levels to prevent ASCVD. In this review, we have discussed the role of PCSK9 in lipid metabolism and briefly summarized the current clinical status of modalities targeting PCSK9. In particular, a detailed overview of peptide-based PCSK9 inhibitors is presented, which emphasizes their structural features and design, therapeutic effects on patients, and preclinical cardiovascular disease (CVD) models, along with PCSK9 modulation mechanisms. As a promising alternative to monoclonal antibodies (mAbs) for managing LDL-C, anti-PCSK9 peptides are emerging as a prospective next generation therapy.

Early Diagnosis of Intracranial Internal Carotid Artery Stenosis Using Extracranial Hemodynamic Indices from Carotid Doppler Ultrasound

Atherosclerotic intracranial internal carotid artery stenosis (IICAS) is a leading cause of strokes. Due to the limitations of major cerebral imaging techniques, the early diagnosis of IICAS remains challenging. Clinical studies have revealed that arterial stenosis may have complicated effects on the blood flow’s velocity from a distance. Therefore, based on a patient-specific one-dimensional hemodynamic model, we quantitatively investigated the effects of IICAS on extracranial internal carotid artery (ICA) flow velocity waveforms to identify sensitive hemodynamic indices for IICAS diagnoses. Classical hemodynamic indices, including the peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive index (RI), were calculated on the basis of simulations with and without IICAS. In addition, the first harmonic ratio (FHR), which is defined as the ratio between the first harmonic amplitude and the sum of the amplitudes of the 1st−20th order harmonics, was proposed to evaluate flow waveform patterns. To investigate the diagnostic performance of the indices, we included 52 patients with mild-to-moderate IICAS (<70%) in a case−control study and considered 24 patients without stenosis as controls. The simulation analyses revealed that the existence of IICAS dramatically increased the FHR and decreased the PSV and EDV in the same patient. Statistical analyses showed that the average PSV, EDV, and RI were lower in the stenosis group than in the control group; however, there were no significant differences (p > 0.05) between the two groups, except for the PSV of the right ICA (p = 0.011). The FHR was significantly higher in the stenosis group than in the control group (p < 0.001), with superior diagnostic performance. Taken together, the FHR is a promising index for the early diagnosis of IICAS using carotid Doppler ultrasound methods.

Relationship between lipid parameters and vascular mechanical characteristics among a normotensive population without diabetes mellitus residing at the Qinghai-Tibet plateau: a cross-sectional study

Background

There is limited evidence regarding the relationship between lipid parameters and vascular mechanical characteristics in the normotensive population without diabetes mellitus. The aim of this study was to identify an association between lipid parameters and changes in vascular mechanical characteristics between men and women, and in women before and after menopause.

Methods

Six hundred-seventy patients who underwent vascular functional testing and who fulfilled the inclusion and exclusion criteria were enrolled in our cross-sectional study. All participants were from the Qinghai–Tibet Plateau (Luhuo County, Ganzi Tibetan Autonomous Prefecture, Sichuan Province, China; mean altitude: 3860 m). Trained clinical physicians assessed brachial-ankle pulse wave velocity (Ba-PWV) and augmentation index adjusted to a 75-beats-per-minute heart rate (AIx@75). To investigate the relationship between lipid parameters and vascular mechanical characteristics in different sexes and menstrual stages, partial correlation analysis and multiple linear regression were used.

Results

The 670 participants comprised 445 women (103 post-menopausal). Mean Ba-PWV and AIx@75 were 1315.56 ± 243.41 cm/s and 25.07% ± 15.84%, respectively. Men had greater Ba-PWV values compared with women (1341.61 ± 244.28 vs 1302.39 ± 242.17 cm/s, respectively; P < 0.05), while AIx@75 values were higher in women compared with men (27.83% ± 15.85% vs 19.64% ± 14.40%, respectively; p < 0.001). In the partial correlation analysis adjusted for age, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and non-high-density lipoprotein cholesterol (HDL-C) were associated with Ba-PWV in both men and women (p < 0.05); however, the magnitude was larger in men. Statistical significance was not seen for AIx@75 among both men and women. Multiple linear regression analysis revealed that TC (β = 0.165, p = 0.024) and non-HDL-C (β = 0.151, p = 0.042) remained independent predictors of change in Ba-PWV in men after adjusting for age, mean arterial pressure, waist circumference, hemoglobin, platelet count, fasting blood glucose, estimated glomerular filtration rate, and uric acid. After adjusting for traditional cardiovascular risk factors, pre-menopausal women had a similar association to that of men between LDL-C (β = 0.126, p = 0.030), non-HDL-C (β = 0.144, p = 0.013), TC/HDL-C (β = 0.162, p = 0.005), LDL-C/HDL-C (β = 0.142, p = 0.013) and Ba-PWV; however, post-menopausal women had no association between the lipid parameters and vascular function.

Conclusions

Overall, TC and non-HDL-C were independent associated factors for vascular compliance alterations evaluated through Ba-PWV in normotensive men. In pre-menopausal women, LDL-C, non-HDL-C, TC/HDL-C and LDL-C/HDL-C were independent associated factors for vascular compliance alterations. After controlling for traditional risk factors, lipid profiles were not associated with these metrics for AIx@75, which can measure the amplification of reflex flow, because of the high number of confounding factors that do not genuinely reflect changes in vascular characteristics. Lipid factors did not appear to be linked to vascular function in post-menopausal women.

Overall and repeated measures agreement between brachial-femoral and carotid-femoral measures of pulse wave velocity in young and healthy individuals

BACKGROUND

Carotid-femoral pulse-wave velocity (cfPWV) is the gold standard measure of arterial stiffness and independently predicts cardiovascular disease. However, obtaining cfPWV requires technical precision and can be difficult in some populations. Brachial-femoral PWV (bfPWV) is a simpler alternative, but there is limited research comparing the two measures. For physiological studies, it is important to know how well the measures agree at rest, and to what extent changes in the measures correspond after perturbation.

OBJECTIVE

To assess the overall and repeated measures agreement between cfPWV and bfPWV.

METHODS

cfPWV and bfPWV were measured in the supine and seated positions, both before and after a 3-h bout of prolonged sitting. The intraclass correlation coefficient (ICC) for overall agreement was calculated using the random variance components from linear mixed-model regression. Repeated measures agreement (change in cfPWV vs. change in bfPWV) was calculated using repeated measures correlation.

RESULTS

Complete data from 18 subjects (22.6 ± 3.1 years old, 33% female) were included in the analysis. There was strong (ICC ≥ 0.70) overall agreement (ICC, 0.75; 95% CI, 0.60-0.85) and very strong (ICC ≥ 0.90) repeated measures agreement (ICC, 0.90; 95% CI, 0.84-0.94) between cfPWV and bfPWV.

DISCUSSION

The current findings indicate strong overall agreement and very strong repeated measures agreement between bfPWV and cfPWV. bfPWV is a user-friendly alternative method that agrees with cfPWV-based assessments of central arterial stiffness.

Evaluation of Intima-Media Thickness and Arterial Stiffness as Early Ultrasound Biomarkers of Carotid Artery Atherosclerosis

Carotid atherosclerosis is a major and potentially preventable cause of ischemic stroke. It begins early in life and progresses silently over the years. Identification of individuals with subclinical atherosclerosis is needed to initiate early aggressive vascular prevention. Although carotid plaque appears to be a powerful predictor of cardiovascular risk, carotid intima-media thickness (CIMT) and arterial stiffness can be detected at the initial phases and, therefore, they are considered important new biomarkers of carotid atherosclerosis. There is a well-documented association between CIMT and cerebrovascular events. CIMT provides a reliable marker in young people, in whom plaque formation or calcification is not established. However, the usefulness of CIMT measurement in the improvement of risk cardiovascular models is still controversial. Carotid stiffness is also significantly associated with ischemic stroke. Carotid stiffness adds value to the existing risk prediction based on Framingham risk factors, particularly individuals at intermediate cardiovascular risk. Carotid ultrasound is used to assess carotid atherosclerosis. During the last decade, automated techniques for sophisticated analysis of vascular mechanics have evolved, such as speckle tracking, and new methods based on deep learning have been proposed with promising outcomes. Additional research is needed to investigate the imaging-based cardiovascular risk prediction of CIMT and stiffness.

Impact of Applying a Skin Compression With the Ultrasound Probe on Carotid Artery Strain Elastography

OBJECTIVE

To study the impact of varying the external compression exerted by the ultrasound probe when performing a carotid strain elastography exam.

METHODS

Nine healthy volunteers (mean age 43 years ±13 years; 6 men) underwent a vascular ultrasound elastography exam using a custom made sound feedback handle embedding the probe, and allowing the sonographer to adjust the applied compression. A clinical standard practice (SP) force was first recorded, and then predetermined compression (PDC) forces were applied, ranging from 0 to 5 N for the left common carotid artery (CCA) or 2-12 N for the left internal carotid artery (ICA). Six carotid elastography features, namely maximum and cumulated axial strains, maximum and cumulated shear strains, cumulated axial translation, and cumulated lateral translation were assessed with noninvasive vascular elastography (NIVE) on near and far walls of carotids. The carotid intima media thickness (IMT) and diameter were also measured.

RESULTS

All elastography features on the near wall of both CCA and ICA decreased statistically significantly as the PDC force increased; this association was also observed for half of the features on the far wall. Three NIVE features at the lowest PDC force (out of 72 that were tested) were statistically significantly different than values at the SP force. Overall, NIVE showed some variance to probe compression with linear regression slopes revealing changes of 10.1%-45.6% in magnitude over the whole compression range on both walls. The maximum IMT for the ICA near wall, and carotid lumen diameters of both CCA and ICA were statistically significantly associated with PDC forces; these features underwent a decrease of 10.2%, 36.2%, and 17.6%, respectively, over the whole range of PDC force increase. Other IMT measurements were not statistically significantly associated with applied PDC forces.

CONCLUSION

These results suggest the need of technical guidelines for carotid strain elastography. Using the lowest probe compression while allowing a good B-mode image quality is recommended to improve the robustness of NIVE measurements.

Placental Maternal Vascular Malperfusion is Associated with Prepregnancy and Early Pregnancy Maternal Cardiovascular and Thrombotic Profiles

Characteristics of maternal vascular malperfusion (MVM) are frequently observed in placentas from pregnancies impacted by preeclampsia, intrauterine growth restriction, preterm labor, and intrauterine fetal demise. We sought to evaluate the associations of features of MVM with subclinical measures of cardiovascular health and coagulation potential in healthy young women. Sixty-three healthy young women were recruited and assessed prior to pregnancy on cycle day 9 ± 4, at gestational age 90 ± 6 of early pregnancy, and gestational age 216 ± 5 of late pregnancy. Women were assessed for plasma volume, blood pressure, response to volume loading, cardiac output, and uterine hemodynamics. Platelet-poor plasma was collected to assess thrombin generation on a subset of 33 women at all time points. Following delivery, placentas were collected and analyzed for evidence of MVM. Thrombin generation (TG) was evaluated in the presence of tissue factor (TF) with and without recombinant soluble thrombomodulin (TM). For each, we compared TG lagtime, peak level, and endogenous thrombin potential (ETP). Comparisons were made between dichotomized presence and absence of each individual feature of MVM and cardiovascular and coagulation features. Mean ± standard deviation are presented. Women were 31 ± 4 years of age, body mass index of 24 ± 5 kg/m2, 86% white race, and 80% nulliparous. MVM occurred in 70% of placentas, with infarcts and agglutination (44%), decidual arteriopathy (40%), accelerated villous maturation (32%), placental hypoplasia (29%), and distal villous hypoplasia (17%) documented. Decidual arteriopathy and distal villous hypoplasia were associated with prepregnancy maternal physiology, including decreased plasma volume and subclinical cardiovascular variations. All assessed MVM characteristics had identifiable early pregnancy physiologic characteristics consistent with altered cardiovascular function and decreased uterine response to pregnancy when compared with women who did and did not develop MVM. Accelerated villous maturation was the only MVM feature to differ by thrombin generation parameters in early pregnancy. Thrombin generation potential and blood pressure were elevated in late pregnancy in women who developed decidual arteriopathy. Prepregnancy health status and adaptation to pregnancy play important roles in pregnancy outcomes. Both cardiovascular health and thrombin generation potential may influence early placentation. Longitudinal assessment of subclinical maternal factors may allow for better understanding of the etiologies of MVM lesions, as well as allow for identification of a timeline of the origins of placental pathologies.

Predictors of the multiwire technique use in carotid artery stenting

OBJECTIVES

The multiwire technique (MWT) in carotid artery stenting (CAS), characterized by the use of more than one guidewire to support guiding catheter in patients with hostile neck anatomy, increases procedural time, enhancing the risk of periprocedural stroke. The aim of the present study was to identify which factors are predictors of the MWT use in CAS, in order to stratify patients with longer procedure at potential higher risk of periprocedural stroke.

METHODS

The study retrospectively included patients who underwent CAS for stenotic plaque between January 2015 and December 2019. Exclusion criteria was incomplete clinical data. For each patients were registered clinical data, main aortic arch and supra-aortic vessel anatomical features, carotid plaque characteristics, and procedural details. The sample was divided in two group on the basis of the number of guides used during the stenting procedure: one guide (standard technique, ST) or more than one guidewire (MWT) to support the guiding catheter. Differences between groups were tested by Chi-square text or Fisher's exact test and Mann-Whitney U test. Logistic regression analysis was used to identify predictors for the use of the MWT. The area under the ROC (AUC) curve was used to assess performance of the model to predict the use of the multiwire technique.

RESULTS

The final sample included 146 of the 204 (71%) patients who underwent CAS during the study period. The median age of the patients was 79 years (IQR 71-83 years) with 47/146 (32%) females. CAS was performed with MWT in 17/146 (12%) of the cases. MWT was used more likely in patients with aortic arch type II or III as compared to ST (71% vs 37%, P = 0.02) while plaques with heavy concentric calcifications were more frequent in ST as compared to MWT (38% vs 12%, P = 0.03). At multivariable analysis aortic arch type II or III (OR 5.08, 95% CI 1.48-17.93, P < 0.01), plaque stenosis > 79% (OR 4.13, 95% CI 1.03-16.61, P = 0.04), and plaque heavy concentric calcifications (OR 0.19, 95% CI 0.04-0.94, P = 0.04) were independent predictors of MWT use. The model showed an AUC of 0.827 (95% CI 0.756-0.884) for the prediction of the MWT use during CAS.

CONCLUSIONS

Aortic arch type II or III, carotid plaque with stenosis higher than 79% of the lumen or without heavy concentric calcifications were predictors for the use of the MWT during CAS. These features should be considered during planning of CAS as hallmark of vascular stiffness and therefore of higher procedure complexity.

Arterial Stiffness in Type 1 Diabetes: The Case for the Arterial Wall Itself as a Target Organ

Arterial stiffness (AS) integrates the cumulative burden of known and unknown cardiovascular risk factors on the elastic wall of large arteries along the lifespan of an individual. As a marker of vascular aging, AS is an independent predictor of cardiovascular events and improves cardiovascular risk prediction when added to the Framingham Risk Score. In addition, AS may affect the microvasculature and promote the development of microvascular complications. Its impact on both the macro- and microvasculature has led to the concept that the arterial wall itself should be considered as a target organ. Here, we review the biological and clinical consequences of AS on the macro- and microvasculature and the measurement of AS in routine clinical practice. We also discuss the pathophysiological mechanisms underpinning AS development using diabetes and, in particular, type 1 diabetes, as a disease model with a high risk of cardiovascular events and microvascular complications that are accelerated by AS.

PCSK9 Biology and Its Role in Atherothrombosis

It is now about 20 years since the first case of a gain-of-function mutation involving the as-yet-unknown actor in cholesterol homeostasis, proprotein convertase subtilisin/kexin type 9 (PCSK9), was described. It was soon clear that this protein would have been of huge scientific and clinical value as a therapeutic strategy for dyslipidemia and atherosclerosis-associated cardiovascular disease (CVD) management. Indeed, PCSK9 is a serine protease belonging to the proprotein convertase family, mainly produced by the liver, and essential for metabolism of LDL particles by inhibiting LDL receptor (LDLR) recirculation to the cell surface with the consequent upregulation of LDLR-dependent LDL-C levels. Beyond its effects on LDL metabolism, several studies revealed the existence of additional roles of PCSK9 in different stages of atherosclerosis, also for its ability to target other members of the LDLR family. PCSK9 from plasma and vascular cells can contribute to the development of atherosclerotic plaque and thrombosis by promoting platelet activation, leukocyte recruitment and clot formation, also through mechanisms not related to systemic lipid changes. These results further supported the value for the potential cardiovascular benefits of therapies based on PCSK9 inhibition. Actually, the passive immunization with anti-PCSK9 antibodies, evolocumab and alirocumab, is shown to be effective in dramatically reducing the LDL-C levels and attenuating CVD. While monoclonal antibodies sequester circulating PCSK9, inclisiran, a small interfering RNA, is a new drug that inhibits PCSK9 synthesis with the important advantage, compared with PCSK9 mAbs, to preserve its pharmacodynamic effects when administrated every 6 months. Here, we will focus on the major understandings related to PCSK9, from its discovery to its role in lipoprotein metabolism, involvement in atherothrombosis and a brief excursus on approved current therapies used to inhibit its action.

Fluid-structure interactions (FSI) based study of low-density lipoproteins (LDL) uptake in the left coronary artery

The purpose of this study is to compare the effect of the different physical factors on low-density lipoproteins (LDL) accumulation from flowing blood to the arterial wall of the left coronary arteries. The three-dimensional (3D) computational model of the left coronary arterial tree is reconstructed from a patient-specific computed tomography angiography (CTA) image. The endothelium of the coronary artery is represented by a shear stress dependent three-pore model. Fluid–structure interaction (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$FSI$$\end{document}FSI) based numerical method is used to study the LDL transport from vascular lumen into the arterial wall. The results show that the high elastic property of the arterial wall decreases the complexity of the local flow field in the coronary bifurcation system. The places of high levels of LDL uptake coincide with the regions of low wall shear stress. In addition, hypertension promotes LDL uptake from flowing blood in the arterial wall, while the thickened arterial wall decreases this process. The present computer strategy combining the methods of coronary CTA image 3D reconstruction, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$FSI$$\end{document}FSI simulation, and three-pore modeling was illustrated to be effective on the simulation of the distribution and the uptake of LDL. This may have great potential for the early prediction of the local atherosclerosis lesion in the human left coronary artery.

Relationship between Pulse Wave Velocity and Cardiovascular Biomarkers in Patients with Risk Factors

BACKGROUND

The relationship between pulse wave velocity (PWV) and biomarkers of structural changes of the left ventricle and carotid arteries remains poorly understood.

OBJECTIVE

To investigate the relationship between PWV and these biomarkers.

METHODS

This was an analytical, retrospective, cross-sectional study. Medical records of patients with diabetes mellitus, dyslipidemia, and pre-hypertension or hypertension, who underwent central blood pressure (CBP) measurement using Mobil-O-Graph®, and carotid doppler or echocardiography three months before and after the CBPM were analyzed. Statistical analysis was performed using Pearson or Spearman correlation, linear bivariate and multiple regression analysis, and the t test (independent) or Mann-Whitney test. A p <0.05 indicated statistical significance.

RESULTS

Medical records of 355 patients were analyzed, mean age 56.1 (±14.8) years, 51% male. PWV was correlated with intima-media thickness (IMT) of carotids (r=0.310) and left ventricular septal thickness (r=0.191), left ventricular posterior wall thickness (r=0.215), and left atrial diameter (r=0.181). IMT was associated with PWV adjusted by age and peripheral systolic pressure (p=0.0004); IMT greater than 1 mm increased the chance of having PWV above 10 m/s by 3.94 times. PWV was significantly higher in individuals with left ventricular hypertrophy (p=0.0001), IMT > 1 mm (p=0.006), carotid plaque (p=0.0001), stenosis ≥ 50% (p=0.003), and target-organ damage (p=0.0001).

CONCLUSION

PWV was correlated with IMT and echocardiographic parameters, and independently associated with IMT. This association was stronger in individuals with left ventricular hypertrophy, increased IMT, carotid plaque, stenosis ≥ 50%, and target organ damage. (Arq Bras Cardiol. 2020; 115(6):1125-1132).

Acute Changes in Carotid-Femoral Pulse-Wave Velocity Are Tracked by Heart-Femoral Pulse-Wave Velocity

Background: Carotid-femoral pulse-wave velocity (cfPWV) is the reference standard measure of central arterial stiffness. However, it requires assessment of the carotid artery, which is technically challenging, and subject-level factors, including carotid artery plaque, may confound measurements. A promising alternative that overcomes these limitations is heart-femoral PWV (hfPWV), but it is not known to what extent changes in cfPWV and hfPWV are associated.

Objectives: To determine, (1) the strength of the association between hfPWV and cfPWV; and (2) whether change in hfPWV is associated with change in cfPWV when central arterial stiffness is perturbed.

Methods: Twenty young, healthy adults [24.0 (SD: 3.1) years, 45% female] were recruited. hfPWV and cfPWV were determined using Doppler ultrasound at baseline and following a mechanical perturbation in arterial stiffness (120 mmHg thigh occlusion). Agreement between the two measurements was determined using mixed-effects regression models and Bland-Altman analysis.

Results: There was, (1) strong (ICC > 0.7) agreement between hfPWV and cfPWV (ICC = 0.82, 95%CI: 0.69, 0.90), and, (2) very strong (ICC > 0.9) agreement between change in hfPWV and cfPWV (ICC = 0.92, 95%CI: 0.86, 0.96). cfPWV was significantly greater than hfPWV at baseline and during thigh occlusion (both P < 0.001). Inspection of the Bland-Altman plot, comparing cfPWV and corrected hfPWV, revealed no measurement magnitude bias.

Discussion: The current findings indicate that hfPWV and cfPWV are strongly associated, and that change in cfPWV is very strongly associated with change in hfPWV. hfPWV may be a simple alternative to cfPWV in the identification of cardiovascular risk in clinical and epidemiological settings.

The systemic implication of novel non-statin therapies in cardiovascular diabetology: PCSK9 as a case model

PCSK9, like other novel non-statin drugs were primarily developed to help patients achieve low-density lipoprotein cholesterol targets, especially in patients with dyslipidemia not achieving lipid goals with statins due to poor tolerance or inadequate response. PCSK9 inhibitors, in addition to modulating lipid metabolism, improve mortality outcomes in cardiovascular disease. These benefits are markedly pronounced in patients with type 2 diabetes mellitus. However, these benefits do not come without associated risk. Multiple trials, studies, and case reports have attempted to explain observed outcomes with PCSK9 expression and administration of PCSK9 inhibitors from multiple perspectives, such as their effects on insulin sensitivity and glucose tolerance, changes in renal physiology, thyroid physiology, vascular tone, intestinal regulation of lipids, and improved cardiovascular function. These agents represent an opportunity for physicians to exercise prudence by using appropriate clinical judgement when managing comorbidities in the hyperglycemic patient, a concept that extends to other novel non-statin drugs.

Long-term trajectories of BMI predict carotid stiffness and plaque volume in type 2 diabetes older adults: a cohort study

BACKGROUND

High body mass index (BMI) is a risk factor for type 2 diabetes and cardiovascular disease. However, its relationships with indices of carotid stiffness and plaque volume are unclear. We investigated associations of long-term measurements of BMI with indices of carotid stiffness and atherosclerosis among non-demented diabetes patients from the Israel Diabetes and Cognitive Decline (IDCD) study.

METHODS

Carotid ultrasound indices [carotid intima media thickness (cIMT), distensibility, elastography and plaque volume] were assessed in N = 471 participants. Mean BMI across all MHS diabetes registry measurements and trajectories of BMI were calculated. BMI was categorized into three trajectory groups representing: a relatively stable normal weight (n = 185, 44%), overweight trajectory (n = 188, 44.8%) and a trajectory of obesity (n = 47, 11.2%). Linear and logistic regressions estimated associations of carotid indices with mean BMI and BMI trajectories.

RESULTS

Compared to the normal weight trajectory, an obesity trajectory was associated with carotid distensibility (β = - 3.078, p = 0.037), cIMT (β = 0.095, p = 0.004), and carotid elastography (β = 0.181, p = 0.004) but not with plaque volume (β = 0.066, p = 0.858). Compared with the normal weight trajectory, an obesity trajectory was associated with increased odds for impaired carotid distensibility (OR = 2.790, p = 0.033), impaired cIMT (OR = 5.277, p = 0.001) and large carotid plaque volume (OR = 8.456, p = 0.013) but not with carotid elastography (OR = 1.956, p = 0.140). Mean BMI was linearly associated with Distensibility (β = - 0.275, p = 0.005) and cIMT (β = 0.005, p = 0.026).

CONCLUSIONS

Long-term measurements of adiposity are associated with indices of carotid stiffness and plaque volume among older type 2 diabetes adults.

Associations between carotid-femoral and heart-femoral pulse wave velocity in older adults: the Atherosclerosis Risk In Communities study

BACKGROUND

Carotid-femoral pulse wave velocity (cfPWV) is widely used in epidemiological studies to assess central arterial stiffness. However, despite being superior to traditional risk factors in predicting cardiovascular outcomes, cfPWV is not routinely used in clinical practice. cfPWV assessments require applanation of the carotid artery, which can be cumbersome, and individual-level factors, including carotid artery plaque, may confound the measurements. Heart-femoral PWV (hfPWV) may be a suitable alternative measure of central arterial stiffness.

OBJECTIVES

The aim of this study was to estimate the strength of the agreement between hfPWV and cfPWV.

METHODS

We evaluated 4133 older-aged [75.2 (5.0) years] African-American and white adults in the community-based Atherosclerosis Risk in Communities (ARIC) Study. cfPWV and hfPWV were measured using an automated cardiovascular screening device. Agreement between the two measurements was determined using Pearson's correlation coefficient (r), standard error of estimate (SEE) and Bland-Altman analysis.

RESULTS

There was a strong (r > 0.7) agreement between hfPWV and cfPWV (r = 0.83, 95% CI: 0.82-0.84). Although the mean cfPWV [11.5 m/s (SD: 3.0)] and hfPWV [11.5 m/s (SD: 2.3)] were comparable, the SEE was 1.7 m/s. Inspection of the Bland-Altman plot revealed greater variability and bias for higher PWV values, with higher PWV further away from the regression line.

DISCUSSION

Findings suggest good agreement between hfPWV and cfPWV. hfPWV is a simpler alternative to cfPWV that is less likely to be confounded by individual-level factors. Considering the greater variability for higher PWV values, further work is warranted to determine the importance of local artery mechanics to both measures.

Assessment of Carotid Artery Distensibility and Elasticity After Laparoscopic Sleeve Gastrectomy: a Prospective Study

PURPOSE

Although it is well known that obesity increases the risk of atherosclerosis in carotid arteries, it is not clear whether this risk changes after obesity surgery. The aim of this study was to investigate whether weight reduction with a laparoscopic sleeve gastrectomy (LSG) has any effect on distensibility and elasticity which show subclinical atherosclerosis in the carotid arteries of obese individuals.

MATERIALS AND METHODS

This prospective study included 130 patients (body mass index (BMI) 48.21 ± 6.97 kg/m²) who underwent LSG. The patients were followed up for 1 year. Comparisons were made of the distensibiliy and elasticity values calculated preoperatively and at 1, 3, 6, and 12 months, postoperatively.

RESULTS

There was a statistically significant increase in distensibility and elasticity values from baseline to 1, 3, 6, and 12 months postoperatively (p < 0.001 for both comparisons). The multiple linear regression analysis was used to find the variables affecting both distensibility and elasticity. According to the results, the presence of BMI decreases distensibility percentage change level by 0.38 units (β= - 0.38, 95% CI - 0.51;- 0.25, p < 0.001). The presence of fasting plasma glucose decreases elasticity percentage change level by 0.20 units. (β= - 0.20, 95% CI - 0.39; - 0.01, p = 0.037).

CONCLUSION

Carotid artery distensibility and elasticity values increase after LSG, and this change could be caused by the change in metabolic parameters and heart geometry. These results may indirectly suggest that subclinical atherosclerosis in carotid arteries has decreased after obesity surgery.

PCSK9 concentrations in different stages of subclinical atherosclerosis and their relationship with inflammation

The aim of this study was to detect the concentrations of PCSK9 in various subclinical stages of atherosclerosis and to highlight its relationship with inflammation. One hundred and fifty-nine healthy patients were divided into three groups, based on the extent of atherosclerotic changes in the carotid artery: a group without identifiable atherosclerosis, cIMT>75‰ and an asymptomatic plaque group. The PCSK9 was measured by ELISA and hsCRP by the immunoturbidimetric method. Vascular changes were identified by a carotid ultrasound. PCSK9 was elevated, when comparing the healthy group with the cIMT>75‰ group; however, no significant increase was detected between cIMT>75‰ and the asymptomatic plaque group. A positive linear correlation of the PCSK9 concentration and atherosclerotic changes was found; however, after the re-analysis in each group, this correlation persisted only in the group with still normal values. Additionally, a significant linear correlation was found between the PCSK9 concentrations and lipid parameters. However, no significant association was found with hsCRP. PCSK9 was found to be elevated only in cIMT>75‰, but not in the later plaque stage. A linear correlation of PCSK9 values was detected only in the group with still reference values. Based on this fact, we assumed the direct linear role of PCSK9 in initiating atherosclerosis; however, in the later phases, the relationship, which highlights other risk factors such as inflammation, is not linear.

Impact of simultaneous measurement of central blood pressure with the SphygmoCor Xcel during MRI acquisition to better estimate aortic distensibility

OBJECTIVES

Aortic distensibility estimation of local aortic stiffness is based on local aortic strains and central pulse pressure (cPP) measurements. Most MRI studies used either brachial PP (bPP) despite differences with cPP, or direct cPP estimates obtained after MRI examination, assuming no major pressure variations. We evaluated the feasibility of assessment of cPP with a specific device fitted with a 6 m long hose (study1) and looked at the influence of using such cPP within the magnet instead of bPP on aortic distensibility in a control population (study 2).

METHODS

Brachial and central pressures values were recorded with the SphygmoCor XCEL system fitted with 2 and 6 m long tubing randomly assigned on arms. A 6 m long tubing was used in the second study to measure aortic distensibility with MRI. Aortic distensibility was calculated using either bPP (bAD) or cPP (cAD).

RESULTS

Study1, performed on 38 patients (mean age: 43 ± 17 years), showed no statistical difference between bPP and cPP measured with 2 or 6 m long tubing (0.41 ± 4.45 and 0.78 ± 3.18 mmHg, respectively, both P = ns). In study 2, cAD provided statistically higher values than bAD (1.87 ± 1.43 10 · mmHg, P < 0.001) especially in younger individuals (3.28 ± 0.86 10 · mmHg). The correlation between age and aortic distensibility was stronger with cAD (r = -0.92; P < 0,001) than with bAD (r = -0.88; P < 0.001).

CONCLUSION

cPP can be estimated with reasonable accuracy during MRI acquisition using a 6 m long tube. Using either cPP or bPP greatly influences aortic distensibility values, especially in young individuals in whom an accurate detection of early or accelerated vascular aging can be of major importance.

Associations of retinal microvascular caliber with large arterial function and structure: A population-based study of 11 to 12 year-olds and midlife adults

OBJECTIVE

We examined associations between retinal microvascular and large arterial phenotypes to explore relationships between the micro- and macro-vasculature in childhood and midlife.

METHODS

Participants were 1288 children (11-12 years, 50.9% female) and 1264 adults (mean age 44 years, 87.6% female) in a cross-sectional population-based study. Exposures were retinal arteriolar and venular caliber quantified from retinal images. Outcomes included arterial function (pulse wave velocity; carotid arterial elasticity) and structure (carotid intima-media thickness). Multivariable regression models were performed adjusting for age, sex, and family socioeconomic position.

RESULTS

In children, one standard deviation wider arteriolar caliber was associated with slower pulse wave velocity (-0.15 SD, 95% CI -0.21, -0.09) and higher elasticity (0.13 SD, 95% CI 0.06, 0.20); per SD wider venular caliber was associated with faster pulse wave velocity (0.09 SD, 95% CI 0.03, 0.15) and lower elasticity (-0.07 SD, 95% CI -0.13, -0.01). The size of adult associations was approximately double. Wider arteriolar caliber was associated with smaller carotid intima-media thickness (-0.09 SD, 95% CI -0.16, -0.03) in adults but not children. Venular caliber and carotid intima-media thickness showed little evidence of association.

CONCLUSIONS

Narrower retinal arterioles and wider venules are associated with large arterial function as early as mid-childhood. Associations strengthen by midlife and also extend to arterial structure, although effect sizes remain small.

Association between Very Low-Density Lipoprotein Cholesterol (VLDL-C) and Carotid Intima-Media Thickness in Postmenopausal Women Without Overt Cardiovascular Disease and on LDL-C Target Levels

Background: atherosclerotic process inexorably advances in patients reaching low-density lipoprotein cholesterol (LDL-C) targets. An attractive hypothesis is that lipoprotein particles (very low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL)), could contribute to residual risk. The present study aims to investigate the relationship between carotid intima-media thickness (IMT) and different lipoprotein subfractions in a cohort of healthy postmenopausal women. Methods: 75 postmenopausal women, at LDL-C target levels without overt cardiovascular disease, underwent biochemical analyses (including subfraction assay of plasma lipoproteins) and carotid ultrasound examination. Results: a statistically significant correlation between VLDL and carotid IMT (p < 0.001) was found. No significant correlation was found between carotid IMT and LDL-C (p = 0.179), IDL-C (p = 0.815), high-density lipoprotein (HDL) (p = 0.855), and LDL score (p = 0.240). Moreover, IMT is significantly correlated to LDL particle diameter (p = 0.044). After adjusting for age, systolic blood pressure, body mass index, smoking habits, glucose plasma concentration, and Lipoprotein(a) (Lpa) levels, multivariate analysis showed that women in the third tertile of VLDL-C, compared with those in the first tertile, were significantly associated to the highest IMT (p = 0.04). Conclusions: in this cohort of postmenopausal women, VLDL-C was significantly associated to carotid IMT, independent of main cardiovascular risk factors. These findings pave the way for targeting circulating concentrations of VLDL-C to reduce cardiovascular events in patients with target LDL-C levels.

Lipoprotein Particle Predictors of Arterial Stiffness after 17 Years of Follow Up: The Malmö Diet and Cancer Study

BACKGROUND

Central arterial stiffness is a surrogate of cardiovascular risk and predicts cardiovascular mortality. Apolipoprotein B lipoproteins are also established cardiovascular risk factors. It is not known whether specific lipoprotein subclasses measured in the Malmö Diet and Cancer Study and previously shown to be associated with coronary heart disease also predict arterial stiffening after a mean period of 17 years.

METHODS

Lipoprotein particle analysis was performed on 2,505 men and women from Malmö, Sweden, from 1991 to 1994, and arterial stiffness was assessed by carotid-femoral pulse wave velocity (c-fPWV) on this same cohort from 2007 to 2012. Associations between c-fPWV and lipoprotein particles were determined with multiple linear regression, controlling for sex, presence of diabetes, waist-to-hip circumference, and smoking status at baseline, as well as heart rate (measured at the carotid artery), mean arterial pressure, antihypertensive and lipid-lowering medications, C-reactive protein (CRP), and age at the time of c-fPWV measurement.

RESULTS

The results confirm that triglycerides (TG) and high-density lipoprotein cholesterol (HDL-c) but not low-density lipoprotein cholesterol (LDL-c) predict c-fPWV. We identify a positive predictive association for very small, small, and medium (high risk), but not large LDL particles. There was a negative association for large HDL particles. The relationships between c-fPWV and high-risk LDL particles were unaffected by adjusting for LDL-c or CRP and were only mildly attenuated by adjusting for the homeostatic model for insulin resistance (HOMA-IR). Due to the collinearity of very small, small, and medium LDL particles and dyslipidemia (elevated TG and decreased HDL-c), the observed relationship between c-fPWV and high-risk LDL particles became insignificant after controlling for the concentration of HDL-c, large cholesterol-rich HDL particles, and TG.

CONCLUSIONS

The development of central arterial stiffness previously associated with combined dyslipidemia may be mediated in part by LDL particles, particularly the very small-, small-, and medium-sized LDL particles.

Matrix stiffening induces endothelial dysfunction via the TRPV4/microRNA-6740/endothelin-1 mechanotransduction pathway

Vascular stiffening is associated with the prognosis of cardiovascular disease (CVD). Endothelial dysfunction, as shown by reduced vasodilation and increased vasoconstriction, not only affects vascular tone, but also accelerates the progression of CVD. However, the precise effect of vascular stiffening on endothelial function and its mechanism is unclear and a possible underlying has not been determined. In this study, we found that increasing substrate stiffness promoted endothelin-1 (ET-1) expression and inhibited endothelial nitric oxide synthase expression in human umbilical vein endothelial cells. Additionally, miR-6740-5p was identified as a stiffness-sensitive microRNA, which was downregulated by a stiff substrate, resulting in increased ET-1 expression. Furthermore, we found that substrate stiffening reduced the expression and activity of the calcium channel TRPV4, which subsequently enhanced ET-1 expression by inhibiting miR-6740-5p. Finally, analysis of clinical plasma samples showed that plasma miR-6740-5p levels in patients with carotid atherosclerosis were significantly lower than those in healthy people. Taken together, our findings show a novel mechanically regulated TRPV4/miR-6740/ET-1 signaling axis by which substrate stiffness affects endothelial function. Our findings indicate that vascular stiffening induces endothelial dysfunction, thereby accelerating progression of CVD. Furthermore, this study indicates that endothelial dysfunction induced by improper biophysical cues from cardiovascular implants may be an important reason for complications arising from the use of cardiovascular implants. STATEMENT OF SIGNIFICANCE: Cardiovascular disease is the leading cause of morbidity and mortality worldwide. The incidence of cardiovascular disease is accompanied by increased vascular stiffness. Our work indicated that increased vascular stiffness accelerates the development of cardiovascular disease by inducing endothelial dysfunction, which is a key contributor to the pathogenesis of cardiovascular disease. In addition, we identified a novel underlying molecular pathophysiological mechanism by which increased stiffness induce endothelial dysfunction. Our work could help determine the pathogenesis of cardiovascular disease induced by biomechanical factors.

Fluid–Solid Interaction Analysis on Iliac Bifurcation Artery: A Numerical Study

Atherosclerosis, which is commonly seen at regions with low wall shear stress (WSS) level in bifurcations, is a kind of fibro-fatty plaque accumulated on arterial walls. Aortic and iliac bifurcations have the highest proportion of patients among all atherosclerosis cases, thus it is necessary to numerically analyze the flow distribution and predict plaque positions in these bifurcations. Furthermore, using fluid–solid interaction (FSI) method could obtain a more exact flow pattern in arteries. In this study, a patient-specific model of aortic and iliac bifurcations was simulated with both FSI and rigid-wall cases. We analyzed the vessel deformation, WSS and flow distribution of this model. Computed tomography (CT) angiography was used in our study to create patient-specific model of aorto-iliac arteries. Real material properties and pulsatile fluid boundary conditions were applied in solid and fluid zones, respectively. We performed FSI and ordinary computational fluid dynamics (CFD) simulations with AYSYS 15.0 software (ANSYS Inc., Canonsburg, PA), and compared the diameter change, WSS and flow field between these two results. The diameter change between systolic phase and diastolic phase is 8–9% on abdominal aorta, and 3% on external and internal iliac arteries. The compliance of vessels corresponds to in-vivo observations. At peak systolic phase, the average WSS obtained in FSI simulation is 10% lower than in rigid-wall result, area of low-WSS region ([Formula: see text]) also increases by 78%. Wall deformation has a greater impact on WSS of those vessels with larger diameter, but hardly changes the shear level in smaller branches. Our result also shows that iliac bifurcations reveal more complicated secondary flow in systolic phase, comparing to other vessels, and stenosed iliac artery has more severe secondary flow than healthy artery. We obtained a feasible method for hemodynamic FSI research. The material parameters, boundary conditions and mesh could be used for further simulations, while the WSS and flow distribution may support clinical diagnosis and treatment. We concluded that compliance is a must-consider factor for simulating an accurate wall shear stress, because the vessel deformation in FSI simulation will significantly change the distribution of low-WSS zones. Moreover, more complicated secondary flow is detected in iliac arteries because it may interact between bifurcations. Stenosis in artery may also have a blocking effect on downstream blood flow.

Uniaxial Tensile Properties of Atherosclerotic Carotid Artery After Mobilization of Pushing on Qiao-Gong: A Safety Study Using an Animal Model of Carotid Atherosclerosis

OBJECTIVES

This study aimed to preliminarily explore the effects of the soft tissue mobilization of pushing on Qiao-Gong (MPQ) on biomechanical properties of the carotid artery using an animal model of carotid atherosclerosis (CAS).

METHODS

Fifty rabbits were randomly divided into 4 groups: animals with CAS treated with MPQ (CAS-MPQ [n = 15]); animals with CAS treated without MPQ (CAS [n = 15]); normal animals treated with MPQ (normal-MPQ [n = 10]); and a blank control group (n = 10). The MPQ procedure consisted of soft tissue mobilization of the Qiao-Gong acupoint on the front edge of the sternocleidomastoid muscle applied from top to bottom, by flat pushing with the thumb repeatedly for 20 times. Disease in the CAS models was induced by carotid artery balloon injury combined with a high-fat diet for 12 weeks. At the end of modeling, carotid color Doppler ultrasonography examination was performed to confirm which animal models were successfully induced with CAS, excluding model rabbits without typical CAS at the same time. Then, MPQ was applied on rabbits in the CAS-MPQ and the normal-MPQ groups for 3 weeks. By contrast, rabbits in the other 2 groups were fed normally without MPQ. Uniaxial failure tests were later performed on carotid arteries in all 4 groups, and at the end of the study, a 2-way factorial analysis of variance of the results was conducted.

RESULTS

(1) At the end of modeling, 10 rabbits in the CAS-MPQ group and 9 in the CAS group were included with typical carotid atherosclerotic characteristics. (2) Young's elastic modulus of the rabbit carotid artery increased more significantly in the CAS-MPQ group than the CAS group. (3) Compared with normal rabbit carotid arteries, atherosclerotic carotid arteries had lower levels of ultimate stress and ultimate strain but higher levels of ultimate load.

CONCLUSIONS

The uniaxial tensile mechanical properties of the rabbit atherosclerotic carotid artery were impaired after MPQ.

[Atherosclerosis of peripheral arteries in patients with coronary artery disease and type 2 diabetes mellitus]

AIM

To study the features of atherosclerosis of peripheral arteries in patients with coronary artery disease (CAD) depending on the presence of type 2 diabetes mellitus (T2DM) and to identify factors associated with multifocal atherosclerosis.

MATERIALS AND METHODS

The study included 140 patients (77 men and 63 women) with CAD (mean age 62.0 (56.0-66.0) years). The first group included 70 people with CAD and T2DM, and the second group included 70 patients with CAD without T2DM. All patients underwent duplex scanning of the carotid and lower limb arteries (LLA). Local vascular stiffness of the common carotid artery (CCA) was assessed by ultrasound scanning. The Peterson elasticity modulus, distensibility and strain of the CCA were determined. The ankle - brachial index (ABI) was measured by the Doppler method.

RESULTS AND DISCUSSION

In the group of patients with T2D, there were statistically more patients with atherosclerotic plaques in both carotid arteries and LLA. Also among patients with T2DM the severity of stenosis of carotid arteries and LLA at all levels was significantly greater. Local carotid stiffness was higher in the first group of patients. The proportion of individuals with reduced ABI.

Impact of atherosclerotic disease on cerebral microvasculature and tissue oxygenation in awake LDLR-/-hApoB+/+ transgenic mice

We explore cortical microvasculature changes during the progression of atherosclerosis using young and old transgenic atherosclerotic (ATX) mice with thinned-skull cranial window. In awake animals, exploiting intrinsic signal optical imaging, Doppler optical coherence tomography, and two-photon microscopy, we investigate how the progression of atherosclerotic disease affects the morphology and function of cortical microvasculature as well as baseline cerebral tissue oxygenation. Results show that aged ATX mice exhibited weaker hemodynamic response in the somatosensory cortex to whisker stimulation and that the diameter of their descending arterioles and associated mean blood flow decreased significantly compared with the young ATX group. Data from two-photon phosphorescence lifetime microscopy indicate that old ATX mice had lower and more heterogeneous partial pressure of oxygen ( PO 2 ) in cortical tissue than young ATX mice. In addition, hypoxic micropockets in cortical tissue were found in old, but not young, ATX mice. Capillary red blood cell (RBC) flux, RBC velocity, RBC velocity heterogeneity, hematocrit, and diameter were also measured using line scans with two-photon fluorescence microscopy. When compared with the young group, RBC flux, velocity, and hematocrit decreased and RBC velocity heterogeneity increased in old ATX mice, presumably due to disturbed blood supply from arterioles that were affected by atherosclerosis. Finally, dilation of capillaries in old ATX mice was observed, which suggests that capillaries play an active role in compensating for an oxygen deficit in brain tissue.

Subclinical cardiac stiffness is associated with arterial stiffness in healthy young nulligravid women: Potential links to preeclampsia

OBJECTIVES

Preeclampsia is an independent risk factor for subsequent cardiovascular disease and diastolic dysfunction and has been linked to arterial stiffness. We hypothesized that arterial stiffness would be associated with echocardiographic markers of diastolic dysfunction in healthy nulligravid women.

STUDY DESIGN

31 healthy nulligravid women underwent assessment of peripheral arterial stiffness via aorto-femoral pulse wave velocity, popliteal distensibility and β stiffness measures as well as hemodynamic response to volume challenge. 22 underwent cardiac assessment via conventional and stress echocardiography with a focus on diastolic function utilizing tissue/pulse wave Doppler imaging and 3D speckle tracking. Bivariate associations between variables were evaluated using correlation coefficients (Pearson r) and Student's t-tests.

RESULTS

No participants had echocardiographic values meeting criteria for overt diastolic dysfunction. Baseline global circumferential strain was significantly correlated with distensibility and β stiffness (n = 18, r = -0.61, p = 0.007, n = 18, r = 0.56, p = 0.01). Peak deceleration time was correlated with βstiffness (n = 9; r = 0.80, p = 0.01). Pulse wave velocity was not significantly correlated with cardiac measures (p > 0.05). Family history of a first or second degree relative with myocardial infarction or hypertension was associated with decreased popliteal artery distensibility (p = 0.02 and p = 0.03, respectively).

CONCLUSIONS

In healthy nulligravid women there is evidence that markers of decreased left ventricular relaxation are associated with increased peripheral vascular stiffness as is a family history of myocardial infarction or hypertension. These findings raise the possibility that the diastolic dysfunction and arterial stiffness observed in the setting of preeclampsia are driven by underlying properties present prior to pregnancy and contribute to lifetime cardiovascular risk.

Body composition is a strong predictor of local carotid stiffness in Swedish, young adults - the cross sectional Lifestyle, biomarkers, and atherosclerosis study

Background

Obesity has nearly tripled worldwide during the last four decades, especially in young adults, and is of growing concern since it is a risk factor for cardiovascular diseases (CVD). We explored how different body composition measurements are associated with intima media thickness (cIMT) and local stiffness in the common carotid artery, in a subsample of healthy, young women and men, from the Swedish Lifestyle, Biomarkers, and Atherosclerosis (LBA) Study.

Methods

From the LBA study, a subsample of 220 randomly selected, self-reported healthy individuals, 18–25 years old, were collected for the automatized local stiffness measurements; arterial distensibility, Young’s elastic modulus, and β stiffness index. Blood pressure and mean arterial pressure (MAP) was measured using automatic blood pressure equipment. Body mass index (BMI) was calculated, waist circumference was measured, and percentage of body fat assessed using an impedance body composition analyzer. The carotid artery was scanned by ultrasound and analyzed using B-mode edge wall tracking. cIMT was measured and local stiffness measurements were calculated with carotid blood pressure, measured with applanation tonometry.

Results

No association was found between cIMT and body composition. Local carotid stiffness was associated with body composition, and women had less stiff arteries than men (p < 0.001). Of the local stiffness measurements, arterial distensibility had the strongest associations with body composition measurements in both women and men (p < 0.05). Multiple regression analyses showed that BMI in women and BMI and percentage of body fat in men had the highest impact on arterial distensibility (p < 0.01 in both women and men).

Conclusions

Arterial distensibility was the local stiffness measurement with the strongest associations to different body composition measurements, in both women and men. In this age group, body composition measurements seem to be stronger predictors of common carotid arterial stiffness than MAP, and is a convenient way of detecting young adults who need cardiovascular risk follow-up and lifestyle counseling.

Arterial Stiffness Assessed by Cardio-Ankle Vascular Index

Arterial stiffness is an age-related disorder. In the medial layer of arteries, mechanical fracture due to fatigue failure for the pulsatile wall strain causes medial degeneration vascular remodeling. The alteration of extracellular matrix composition and arterial geometry result in structural arterial stiffness. Calcium deposition and other factors such as advanced glycation end product-mediated collagen cross-linking aggravate the structural arterial stiffness. On the other hand, endothelial dysfunction is a cause of arterial stiffness. The biological molecular mechanisms relating to aging are known to involve the progression of arterial stiffness. Arterial stiffness further applies stress on large arteries and also microcirculation. Therefore, it is closely related to adverse outcomes in cardiovascular and cerebrovascular system. Cardio-ankle vascular index (CAVI) is a promising diagnostic tool for evaluating arterial stiffness. The principle is based on stiffness parameter β, which is an index intended to assess the distensibility of carotid artery. Stiffness parameter β is a two-dimensional technique obtained from changes of arterial diameter by pulse in one section. CAVI applied the stiffness parameter β to all of the arterial segments between heart and ankle using pulse wave velocity. CAVI has been commercially available for a decade and the clinical data of its effectiveness has accumulated. The characteristics of CAVI differ from other physiological tests of arterial stiffness due to the independency from blood pressure at the time of examination. This review describes the pathophysiology of arterial stiffness and CAVI. Molecular mechanisms will also be covered.

PCSK9 inhibition and inflammation: A narrative review

Atherosclerotic cardiovascular disease (ASCVD) remains a leading cause of morbidity and mortality despite excellent pharmacological and revascularization approaches. Low-density lipoproteins (LDL) are undoubtedly the most significant biochemical variables associated with atheroma, however, compelling data identify inflammation as critical for the maintenance of the atherosclerotic process, underlying some of the most feared vascular complications. Although its causal role is questionable, high-sensitivity C-reactive protein (hs-CRP) represents a major biomarker of inflammation and associated risk in CVD. While statin-associated reduced risk may be related to the lowering of both LDL-C and hs-CRP, PCSK9 inhibitors leading to dramatic LDL-C reductions do no alter hs-CRP levels. On the other hand, hs-CRP levels identify groups of patients with a high risk of CV disease achieving better ASCVD prevention in response to PCSK9 inhibition. In the FOURIER study, even in patients with extremely low levels of LDL-C, there was a stepwise risk increment according to the values of hs-CRP: +9% (<1 mg/L), +10.8% (1-3 mg/L) and +13.1% (>3 mg/L). Likewise, in the SPIRE-1 and -2 studies, bococizumab patients with hs-CRP> 3 mg/L had a 60% greater risk of future CV events. Most of the patients enrolled in the PCSK9 trials were on maximally tolerated statin therapy at baseline, and an elevated hs-CRP may reflect residual inflammatory risk after standard LDL-C lowering therapy. Moreover, data on changes in inflammation markers in carriers of PCSK9 loss-of-function mutations are scanty and not conclusive, thus, evidence from the effects of anti-inflammatory molecules on PCSK9 levels might help unravel this hitherto complex tangle.

Von Mises Strain as a Risk Marker for Vulnerability of Carotid Plaque: Preliminary Clinical Evaluation of Cerebral Infarction

Non-invasive assessment of carotid artery plaque vulnerability is a key issue for cerebrovascular disease. This study investigates Von Mises strain imaging in patients by relating Von Mises strain to cerebral infarction presentation. Ultrasonography was performed in patients evaluated for carotid artery stenosis. Strains were estimated by a flow-driven diffusion method and least-squares regression applying Kalman filtering. Von Mises strains ɛ_VM^sys and ɛ_VM^dia were calculated by averaging four or five cardiac cycles in systole and diastole, respectively. Von Mises strain (peak, coefficient of variance, skewness and kurtosis) in patients with cerebral infarction was compared with that in the control group. Higher Von Mises peak strain localized to echolucent areas on B-mode imaging. Higher peak strain was found in patients with cerebral infarction compared with the control group (p = 0.02 for ɛ_VM^dia and p = 0.001 for ɛ_VM^sys). The area under the receiver operating characteristic curve for peak ɛ_VM^sys was 0.761 (p = 0.001) with high sensitivity and specificity. Peak strain also correlated with homocysteine (r = 0.345, p = 0.007, for ɛ_VM^dia; r = 0.287, p = 0.036, for ɛ_VM^sys) and hypersensitive C-reactive protein (r = 0.399, p = 0.043, for ɛ_VM^dia; r = 0.195, p = 0.034, for ɛ_VM^sys) levels. The coefficient of variance, skewness and kurtosis of ɛ_VM^dia or ɛ_VM^sys were also associated with homocysteine levels. In conclusion, this study indicates that peak Von Mises strain is a potential clinical risk marker for carotid plaque vulnerability and cerebral infarction.

Effects of Cervical Rotatory Manipulation on Internal Carotid Artery in Hemodynamics Using an Animal Model of Carotid Atherosclerosis: A Safety Study

BACKGROUND Spinal manipulation, particularly in cervical rotatory manipulation (CRM), has become increasingly popular in physical therapies, with satisfying effect. However, it is still unclear whether CRM affects internal carotid arteries (ICA) with mild carotid atherosclerosis (CAS), especially in hemodynamics. MATERIAL AND METHODS Nine cynomolgus monkeys were randomly divided into 3 groups: the CAS-CRM, the CAS, and the blank control groups. CAS models were developed in the left ICA in the CAS-CRM and the CAS groups. The monkeys in the CAS-CRM group underwent CRM intervention for 3 weeks. Histology and hemodynamics were measured, including peak systolic velocity (PSV), end-diastolic velocity (EDV), time average velocity (TAV), resistance index (RI), and pulsatility index (PI). Measurements were made separately at 3 different rotation angles (0°, 45°, and 90°). RESULTS In the 3 groups, with the increase of rotation angle, the decreasing tendency of PSV, EDV, and TAV and the increasing tendency of RI and PI were statistically significant. At each angle, the monkeys in the CAS-CRM and the CAS groups had lower levels of PSV, EDV, and TAV and higher levels of RI and PI compared with the blank control group. No significant difference in hemodynamics was found between the CAS-CRM and the CAS groups. CONCLUSIONS Both the rotational angle and the atherosclerotic disease can affect the blood flow of the ICA. However, CRM does not cause adverse effects on hemodynamics in cynomolgus monkeys with mild CAS, and appears to be a relatively safe technique.

Cardiovascular inflammation: RNA takes the lead

Inflammation has recently gained tremendous attention as a key contributor in several chronic diseases. While physiological inflammation is essential to counter a wide variety of damaging stimuli and to improve wound healing, dysregulated inflammation such as in the myocardium and vasculature can promote cardiovascular diseases. Given the high severity, prevalence, and economic burden of these diseases, understanding the factors involved in the regulation of physiological inflammation is essential. Like other complex biological phenomena, RNA-based processes are emerging as major regulators of inflammatory responses. Among such processes are cis-regulatory elements in the mRNA of inflammatory genes, noncoding RNAs directing the production or localization of inflammatory cytokines/chemokines, or pathogenic RNA driving inflammatory responses. In this review, we describe several specific RNA-based molecular mechanisms by which physiological inflammation pertaining to cardiovascular diseases is regulated. These include the role of AU-rich element-containing mRNAs, long non-coding RNAs, microRNAs, and viral RNAs.

Assessment of Carotid Artery Plaque Components With Machine Learning Classification Using Homodyned-K Parametric Maps and Elastograms

Quantitative ultrasound (QUS) imaging methods, including elastography, echogenicity analysis, and speckle statistical modeling, are available from a single ultrasound (US) radio-frequency data acquisition. Since these US imaging methods provide complementary quantitative tissue information, characterization of carotid artery plaques may gain from their combination. Sixty-six patients with symptomatic ( n = 26 ) and asymptomatic ( n = 40 ) carotid atherosclerotic plaques were included in the study. Of these, 31 underwent magnetic resonance imaging (MRI) to characterize plaque vulnerability and quantify plaque components. US radio-frequency data sequence acquisitions were performed on all patients and were used to compute noninvasive vascular US elastography and other QUS features. Additional QUS features were computed from three types of images: homodyned-K (HK) parametric maps, Nakagami parametric maps, and log-compressed B-mode images. The following six classification tasks were performed: detection of 1) a small area of lipid; 2) a large area of lipid; 3) a large area of calcification; 4) the presence of a ruptured fibrous cap; 5) differentiation of MRI-based classification of nonvulnerable carotid plaques from neovascularized or vulnerable ones; and 6) confirmation of symptomatic versus asymptomatic patients. Feature selection was first applied to reduce the number of QUS parameters to a maximum of three per classification task. A random forest machine learning algorithm was then used to perform classifications. Areas under receiver-operating curves (AUCs) were computed with a bootstrap method. For all tasks, statistically significant higher AUCs were achieved with features based on elastography, HK parametric maps, and B-mode gray levels, when compared to elastography alone or other QUS alone ( ). For detection of a large area of lipid, the combination yielding the highest AUC (0.90, 95% CI 0.80-0.92, ) was based on elastography, HK, and B-mode gray-level features. To detect a large area of calcification, the highest AUC (0.95, 95% CI 0.94-0.96, ) was based on HK and B-mode gray level features. For other tasks, AUCs varied between 0.79 and 0.97. None of the best combinations contained Nakagami features. This study shows the added value of combining different features computed from a single US acquisition with machine learning to characterize carotid artery plaques.

Ultrasonic assessment of liver stiffness and carotid artery elasticity in patients with chronic viral hepatitis

BACKGROUND

This study investigated the relationship between liver stiffness and carotid artery elasticity in patients with chronic viral hepatitis. We used an acoustic radiation force impulse (ARFI) technique to measure stiffness, and a radio frequency (RF) vascular quantitative ultrasound technique to measure changes in common carotid artery elasticity and vascular function.

METHODS

Two-hundred seventeen patients with chronic viral hepatitis caused by either hepatitis B virus (HBV) or hepatitis C virus (HCV) were enrolled. We divided the patients into two groups, one comprising 147 patients with chronic hepatitis B (CHB) (98 men and 49 women, average age 46.5 ± 12.2 years) and another comprising 70 patients with chronic hepatitis C (CHC) (47 men and 23 women, average age 47.6 ± 12.1 years). Additionally, 64 healthy age- and sex-matched participants (43 men and 21 women, average age 47.8 ± 5.1 years) were selected as the control group. The ARFI technique was used to measure liver stiffness and the RF ultrasound technique was used to measure carotid artery elasticity parameters including intima-media thickness (IMT), pulse wave velocity (PWV), arterial wall dilation coefficient (DC), compliance coefficient (CC), sclerosis indices α and β, and augmentation index (Aix). Clinical indicators, liver stiffness, and carotid artery elasticity parameters were observed and compared between the different age groups to investigate the correlation between carotid artery elasticity parameters and liver stiffness.

RESULTS

The ARFI values for the CHB and CHC groups were significantly higher than those for the control group (1.84 ± 0.52 vs. 1.04 ± 0.11 m/s; 1.86 ± 0.37 vs. 1.04 ± 0.11 m/s, respectively; P < 0.001). When compared to the control group, both CHB and CHC groups showed an IMT of the same order, but had significantly higher elasticity parameters, such as α and β, as well as lower DC and CC values (P < 0.001). The PWV of the CHC group was significantly higher than that of the control group (7.98 ± 1.42 vs. 6.09 ± 0.90 m/s, P < 0.001). In the CHB group, all parameters including ARFI, IMT, PWV, DC, CC, α and β, were significantly different between the two age groups (P < 0.05). Within the CHC group, all parameters including IMT, PWV, DC, α and β, were significantly different between the two age groups (P < 0.05), except for ARFI, wherein the difference was not statistically significant. The correlation analysis and stepwise multiple linear regression analysis indicated that for patients with CHB, age was an independent predictor of common carotid artery IMT (R² = 0.468, F = 54.635, and P < 0.001). For patients with CHC, age and blood sugar were independent predictors of common carotid artery IMT (R² = 0.465, F = 29.118, and P < 0.001).

CONCLUSION

Although based on ARFI and RF ultrasound, the carotid artery IMT in patients with CHB and CHC was not significantly higher than that in the control group, their functional elasticity parameters had already changed. This finding serves as a useful reference for the clinical diagnosis of vascular diseases in patients with viral hepatitis.

TRIAL REGISTRATION

ClinicalTrials: ChiCTR1800015859 25/04/2018.

Carotid Artery Stiffness Assessment by Ultrafast Ultrasound Imaging: Feasibility and Potential Influencing Factors

OBJECTIVES

To evaluate the feasibility of the ultrafast ultrasound pulsed wave velocity (PWV) for carotid stiffness assessment and potential influencing factors.

METHODS

Ultrafast PWV measurements of 442 carotid arteries in 162 consecutive patients (patient group) and 66 healthy volunteers (control group) were performed. High- and very high-frequency transducers were used in 110 carotid segments. The ultrafast PWVs at the beginning and end of systole were automatically measured. The correlations between the intima-media thickness (IMT) and ultrafast PWV and the equipment and carotid factors influencing the utility of ultrafast PWV were analyzed.

RESULTS

Each ultrafast PWV acquisition was completed within 1 minute. The intraobserver variability showed mean differences ± SD of 0.12 ± 1.28 m/s for the PWV before systole and 0.06 ± 1.30 m/s for the PWV at the end of systole. Ultrafast PWV measurements were more likely obtained with the very high- frequency transducer when the IMT was less than 1.5 mm (P < .05). A generalized linear mixed-effects model analysis showed that the very high-frequency transducer had a greater ability to obtain a valid carotid ultrafast PWV measurement with an IMT of less than 1.5 mm (P < .05). The IMT was positively correlated with the PWV before systole and at the end of systole (r = 0.207-0.771; all P < .05) in the control group, patient group, and carotid subgroup with an IMT of less than 1.5 mm. A multiple regression analysis showed that the IMT and plaque were important independent factors in predicting failure of the ultrafast PWV (P < .001).

CONCLUSIONS

The ultrafast PWV is an effective and user-friendly method for evaluating carotid stiffness. The IMT and transducer type are factors influencing the ability to obtain an ultrafast PWV measurement.