Plaque Characteristics Research Articles

Correlation of intracranial and extracranial carotid atherosclerotic plaque characteristics with ischemic stroke recurrence: a high-resolution vessel wall imaging study

ObjectivesTo evaluate the ability of the plaque characteristics of extracranial carotid and intracranial arteries to predict large atherosclerotic ischemic stroke recurrence via head and neck combined high-resolution vessel wall imaging (HR-VWI).MethodsThis prospective cohort study included 169 patients with large atherosclerotic ischemic stroke who underwent head and neck combined HR-VWI from April 2022 to May 2023. The baseline clinical data and atherosclerotic plaque characteristics of the intracranial and extracranial carotid arteries were collected, and the patients were followed up for 1 year, with the endpoint event defined as recurrent ischemic stroke. Clinical and imaging data were compared between the recurrent and nonrecurrent groups. Independent risk factors associated with stroke recurrence were assessed via multivariate Cox regression analysis. The receiver operating characteristic (ROC) curves of the relevant variables were also plotted, and the area under the curve (AUC) was calculated to assess their ability to predict stroke recurrence. Kaplan–Meier survival curves were used to compare the probability of stroke recurrence.ResultsDuring the 12-month follow-up, stroke recurrence occurred in 35 of the 169 patients. Multivariate Cox regression analysis revealed that the total number of intracranial and extracranial carotid plaques (p = 0.010) and coexisting extracranial carotid plaques and intracranial significantly enhanced plaques (p = 0.047) were independent risk factors for recurrent ischemic stroke. The AUCs for predicting stroke recurrence were 0.787 and 0.710, respectively. The Kaplan–Meier survival curve revealed that the risk of stroke recurrence was significantly greater in patients whose total number of intracranial and extracranial carotid plaques was >4.5 than in patients whose total number of plaques was <4.5 (p < 0.001) and was significantly greater in patients with coexisting extracranial carotid plaques and intracranial significantly enhanced plaques than in patients without coexisting plaques (p < 0.001).ConclusionA greater total number of intracranial and extracranial carotid plaques and the coexistence of extracranial carotid plaques and intracranially significantly enhanced plaques are independent risk factors associated with recurrent ischemic stroke. Head and neck combined HR-VWI may provide new indicators for the prediction of stroke recurrence, thus helping clinicians identify high-risk patients and target therapy to reduce the recurrence of ischemic events.

Carotid artery atherosclerosis: mechanisms of instability and clinical implications.

Cardiovascular disease remains a prominent cause of disability and premature death worldwide. Within this spectrum, carotid artery atherosclerosis is a complex and multifaceted condition, and a prominent precursor of acute ischaemic stroke and other cardiovascular events. The intricate interplay among inflammation, oxidative stress, endothelial dysfunction, lipid metabolism, and immune responses participates in the development of lesions, leading to luminal stenosis and potential plaque instability. Even non-stenotic plaques can precipitate a sudden cerebrovascular event, regardless of the degree of luminal encroachment. In this context, carotid imaging modalities have proved their efficacy in providing in vivo characterization of plaque features, contributing substantially to patient risk stratification and clinical management. This review emphasizes the importance of identifying high-risk individuals by use of current imaging modalities, biomarkers, and risk stratification tools. Such approaches inform early intervention and the implementation of personalized therapeutic strategies, ultimately enhancing patient outcomes in the realm of cardiovascular disease management.

Impact of diabetes mellitus on coronary artery plaque characteristics and outcomes in the SCOT-HEART trial.

Diabetes mellitus is an established cardiovascular risk factor. We assessed the impact of diabetes mellitus on quantitative plaque and long-term outcomes in patients with and without diabetes mellitus in the Scottish COmputed Tomography of the HEART (SCOT-HEART) trial. Coronary artery calcium (CAC) was assessed on non-contrast computed tomography (CT). Coronary stenoses, visually assessed adverse plaque characteristics and quantitative plaque burdens (calcified, non-calcified, low attenuation and total, Autoplaque 2.5) were assessed on coronary CT angiography. Multivariable and survival analyses were performed. Images of 1769 patients were assessed (56​% male, 58​±​9 years). Diabetes mellitus was present in 196 (11​%) patients. Patients with diabetes mellitus had higher 10-year cardiovascular risk score (29 [interquartile range 21, 40] versus 15 [9, 21] %, p​<​0.001) and CAC score (71 [1, 447] versus 17 [0, 209] Agatston units, p​<​0.001), but were not more likely to have obstructive disease or visually assessed adverse plaque characteristics. Patients with diabetes mellitus had higher quantitatively assessed calcified, non-calcified, low attenuation and total plaque burdens. After adjustment for age and sex, diabetes mellitus was an independent predictor of calcified plaque burden (p​=​0.009), but not the other plaque types. During 8.7 [IQR 8, 9.6] years follow-up, diabetes mellitus was associated with an increased risk of fatal or non-fatal myocardial infarction, adjusted for age and sex (hazard ratio 1.85, 95​% confidence interval 1.09 to 3.17, p​=​0.024). Diabetes mellitus was an independent predictor of quantitatively assessed plaque burden, particularly calcified plaque, and was associated with an increased risk of myocardial infarction.

Prognostic Value of Serum TMAO Measurement in Patients with STEMI: A Systematic Literature Review.

Gut microbiota-derived metabolite Trimethylamine-N-oxide (TMAO) is increasingly recognized as a potential novel prognostic biomarker for cardiovascular disease. Our research work aimed to investigate the potential utility of TMAO measurement in patients with STelevation Myocardial Infarction (STEMI). We performed a systematic literature search in PubMed from inception to the 1st of February 2024 to identify all studies examining the association between plasma TMAO levels and disease complexity or clinical outcomes in STEMI patients. A total of eight prospective cohort studies were included, encompassing a total of 2,378 STEMI patients. Three of the studies provided only in-hospital evidence (i.e., increased odds for more severe coronary artery disease, plaque rupture, and plaque healing in patients with increased TMAO levels). Four studies examined the long-term prognostic value of TMAO after 10-12 months of follow-up post-STEMI (i.e., increased risk of adverse cardiovascular events in patients with increased TMAO levels), while one study provided data for both in-hospital and mid-term prognosis, indicating that 4-months after STEMI patients with greater TMAO elevation had larger infarct size. Higher TMAO levels were associated with a greater prevalence of high-risk coronary plaque characteristics and worse in-hospital and follow-up outcomes in STEMI patients. Further study is needed on whether modulating the diet-dependent TMAO levels could improve clinical outcomes in these patients. [(OSF): https://doi.org/10.17605/OSF.IO/WNG8V].

Macrophage-based pathogenesis and theranostics of vulnerable plaques.

Vulnerable plaques, which are high-risk features of atherosclerosis, constitute critical elements in the disease's progression due to their formation and rupture. Macrophages and macrophage-derived foam cells are pivotal in inducing vulnerability within atherosclerotic plaques. Thus, understanding macrophage contributions to vulnerable plaques is essential for advancing the comprehension of atherosclerosis and devising novel therapeutic and diagnostic strategies. This review provides an overview of the pathological characteristics of vulnerable plaques, emphasizes macrophages' critical role, and discusses advanced strategies for their diagnosis and treatment. It aims to present a comprehensive macrophage-centered perspective for addressing vulnerable plaques in atherosclerosis.

Coronary plaque characteristics quantified by artificial intelligence-enabled plaque analysis: Insights from a multi-ethnic asymptomatic US population

Coronary plaque characteristics quantified by artificial intelligence-enabled plaque analysis: Insights from a multi-ethnic asymptomatic US population

Coronary Plaque Characteristics Assessed by Optical Coherence Tomography and Plasma Lipoprotein(a) Levels in Patients With Acute Coronary Syndrome.

Lipoprotein(a) [Lp(a)] is associated with increased cardiovascular risk, but its influence on plaque characteristics at optical coherence tomography (OCT) evaluation is not fully understood. This study seeks to explore the impact of Lp(a) levels on plaque morphology as assessed by OCT in a very high-risk subset of patients. Consecutive patients admitted for acute coronary syndrome (ACS) and undergoing OCT-guided percutaneous coronary intervention (PCI) at a large tertiary care center between 2019 and 2022 were deemed eligible for the current analysis. The overall population was categorized into two subgroups according to baseline Lp(a) levels: (1) lower Lp(a) (Lp(a) ≤ 300 mg/L) and (2) elevated Lp(a) (Lp(a) 300 mg/L). Predictors of lipid-rich plaques were identified using multivariable logistic regression with stepwise selection of candidate covariates. A total of 202 patients were included in this study. OCT findings revealed that patients with elevated Lp(a) had a higher prevalence of lipid-rich plaques, a significantly greater mean lipid arc, along with increased macrophage infiltration and thin-cap fibroatheroma (TCFA). In contrast, calcific plaque prevalence was higher in the lower Lp(a) group. Multivariable regression analysis identified low-density lipoprotein cholesterol ≥ 70 mg/dL, and elevated Lp(a) as strong predictors of lipid-rich plaques at OCT. In this observational study including ACS patients undergoing OCT-guided PCI, those with elevated Lp(a) levels exhibited a higher prevalence of lipid-rich plaques, increased macrophage infiltration, and TCFA, thereby indicating a more vulnerable plaque phenotype. Additionally, elevated Lp(a) levels and LDL-C levels ≥ 70 mg/dL were each independently associated with lipid enrichment of coronary plaques. These findings suggest Lp(a), beyond other well-known risk factors, as a key marker for risk stratification, potentially informing optimal medical management strategies.

Characteristics of Atherosclerotic Plaques Left after Percutaneous Coronary Intervention in Patients with Acute Coronary Syndrome. Assessment According to Computed Tomographic Angiography of the Coronary Arteries.

To evaluate characteristics of atherosclerotic plaques (ASP) remaining after percutaneous coronary intervention (PCI) in patients with acute coronary syndrome (ACS) by coronary computed tomography angiography (CCTA). Among 249 patients (193 men) with ACS aged 58±10 years, 183 (73.5%) had myocardial infarction, 66 (26.5%) had unstable angina. CCTA was performed after PCI at 3-7 days after the onset of ACS according to the standard protocol: in 41 patients, on a 64-slice tomograph (Aquilion 64, Toshiba, Japan) and in 208 patients, on a 640-slice tomograph with 320 rows of detectors (Aquilion ONE Vision Edition, Toshiba, Japan). CCTA of all patients was performed on a Vitrea workstation. Patients with at least one non-calcified ASP were included. Among all ASPs, non-calcified ASPs predominated, 609 of 785 (77.6%), including 400 soft and 209 combined ones. Signs of obstruction (stenosis ≥50%) were noted in 72.2% of non-calcified ASPs. ASPs were characterized by a pronounced burden, 69 [61.4; 74.2]%, and a low minimum density, 31 [23; 37] HU, which was consistent with mature plaques with a lipid core. Various signs of ASP instability were observed in 6-35.3% of cases. There were 2 [2;3] (1 to 6) affected coronary arteries (CAs) and 3 [2;4] (1 to 7) ASPs, including calcified ones, per patient. 77.7% of ASPs were located in the CA proximal and middle segments. Obstructive stenosis was detected in 92% of patients. The number of ASPs with obstructive stenosis ranged from 0 to 7 per patient, with a median of 2 [1;3]. In 44% of patients, stenosis was 70% or more. The maximum burden of non-calcified ASPs was high, 74.3±12.1%; their maximum and total length were 13.8±10.4 mm and 26.5±19.7 mm, respectively; and the ASP minimum density was low, 25 [17;32] HU. ASPs with a low-density area of ≤46 HU and ≤30 HU were detected in 24.9% and 14.8% of patients, respectively. Other CCTA signs of instability were quite common: punctate calcifications in 52.2% of patients, coronary positive remodeling in 37%, the presence of "ring-like enhancement" in 16.1%, an uneven plaque contour in 26.7%, and at least one sign of ASP instability in 73% of patients. After PCI, patients with ACS still have rather many ASPs, including those with CCTA signs of instability, with stenosis &gt;50%; more than a third of the plaques had stenosis &gt;70%; the plaques were extended and localized mainly in the proximal and middle sections of the main CAs.

Non-Stenotic Carotid Plaques and Rate of DWI-positive MRI in Patients with Lower-Risk Transient or Persistent Minor Neurologic Events: DOUBT Sub Study.

Non-stenotic (< 50%) carotid plaques are increasingly recognized as apotential mechanism for ischemic stroke. We assessed the prevalence of such plaques in patients with low-risk neurologic events and evidence of DWI (Diffusion Weighted Imaging)-positive ischemia. This is apost-hoc exploratory analysis from the DOUBT study, aprospective, observational, multicenter study of patients with low-risk transient or persistent minor focal neurological symptoms. Patients who had baseline CT angiography (CTA) and an MRI within 8days of their event were included in the study. We aimed to assess the prevalence of non-stenotic carotid disease in patients with versus without DWI-positive events, and in patients with ipsilateral DWI-positive events. Acarotid-level analysis with univariable logistic regression analysis was performed to assess whether any of the assessed plaque features were associated with ipsilateral stroke. Of the 334 patients (mean age 62.7 years, 50.4% females) with available vascular neuroimaging, 153 (45.9%) had non-stenotic carotid plaques (≤50% stenosis), 174 (52.1%) had no stenosis and 7 (2.1%) patients had >50% stenosis. Of those with non-stenotic carotid plaques, 31/153 (20.3%) had evidence of DWI-positive ischemia, approximately half (15/31; 48.4%) of which was in the territory of the carotid plaque. Amongst patients with DWI-positive ischemia, non-stenotic plaques were significantly more common on the side of DWI-positive lesions [31/49 (63.3%) versus 18/49(36.7%)]. Presence of non-stenotic plaque was arisk marker for DWI-positive events (RR 1.4, 95% CI 1.1-1.8, p 0.012). On matched analysis, non-stenotic plaques were more likely on the side of DWI+ ischemia (odds ratio 1.14, 95% CI 0.36-3.70, McNemar's p value 0.80). Plaque features, including hypodensity, irregularity and greater plaque thickness were significantly associated with ahigher likelihood of ipsilateral DWI+ ischemia. In patients with low-risk transient or persistent neurologic events, non-stenotic carotid plaques are more common in patients with DWI-positive ischemia. Plaque features like hypodense and irregular plaque were more common with DWI-positive changes in the territory of the affected carotid.

Plaque characteristics associated with failure of primary balloon angioplasty for intracranial atherosclerotic stenosis: a retrospective study

BackgroundPrimary balloon angioplasty (PBA) is an alternative treatment approach for intracranial atherosclerotic stenosis (ICAS); however, its efficacy may be compromised by arterial dissection or early elastic recoil after balloon dilation....

Nonstenotic carotid artery plaques on computed tomography angiography in embolic stroke of undetermined source.

This study aims to evaluate the role of <50% stenotic cervical carotid artery plaques in embolic stroke of undetermined source (ESUS), focusing on plaque characteristics in symptomatic versus asymptomatic carotid arteries (contralateral). In this cross-sectional observational study, 81 patients who met the diagnostic criteria for ESUS and underwent were retrospectively analyzed. Carotid plaques causing <50% stenosis were examined, noting features such as plaque thickness, degree of luminal stenosis, irregularity, ulceration, calcification, and hypodensity. These characteristics were compared between the ipsilateral and contralateral carotid arteries. The study involved 33 men and 48 women, with plaques ≥3mm thick significantly more common in the ipsilateral carotid arteries (P < .05). Notable features such as plaque ulceration, irregularity, noncalcified plaque, and hypodensity were significantly more frequent ipsilaterally (P < .05). Of the plaque patients, 54.3% (44/81) were on the ipsilateral side, compared to 29.6% (24/81) on the contralateral side (P = .0024). Our findings underscore the potential significance of non-stenotic carotid plaques in ESUS. These plaques, especially those with certain high-risk characteristics, are more prevalent ipsilaterally and should be considered in clinical evaluations and treatment of ESUS.

Relationship Between Coronary Artery Calcium Score and Vulnerability of Culprit Plaque Assessed by OCT in Patients With Established Coronary Artery Disease.

Coronary artery calcium score (CACS) is widely used for risk stratification. However, in patients with established coronary artery disease, its clinical implication and relationship with plaque vulnerability are unclear. We sought to correlate the CACS and plaque vulnerability assessed by optical coherence tomography. Patients with coronary artery disease who had CACS and optical coherence tomography before percutaneous coronary intervention were included. Patients were divided into 5 groups based on CACS: CACS of 0, 1 to 99, 100 to 399, 400 to 999, and ≥1000. Optical coherence tomography-derived vulnerable features in culprit plaque were compared between the groups. In 460 patients, the prevalence of lipid-rich plaque, macrophage, and cholesterol crystal significantly differed among the 5 groups, being lowest in the patients with a CACS of 0. The prevalence of thin-cap fibroatheroma tended to be lower in those with a CACS of 0. No significant difference in vulnerable features was observed between the 4 groups with CACS >0. In the 2-group comparison between the group with a CACS of 0 and the other 4 groups combined, the prevalence of lipid-rich plaque (60.5% versus 85.9%; P<0.001), macrophage (48.8% versus 74.1%; P<0.001), thin-cap fibroatheroma (16.3% versus 35.0%; P=0.013), and cholesterol crystal (11.6% versus 32.9%; P=0.004) was significantly lower in the patients with CACS of 0. CACS of 0 was independently negatively associated with lipid-rich plaque, macrophage, thin-cap fibroatheroma, and cholesterol crystal after adjustment for patient characteristics. Patients with a CACS of 0 have a significantly lower prevalence of vulnerable plaque features compared with those with CACS >0 in patients with established coronary artery disease. URL: https://www.clinicaltrials.gov; Unique identifier: NCT04523194.

Atherosclerotic plaque evolution predicts cerebral ischemic events in patients with intracranial atherosclerosis: a multicentre longitudinal study using high-resolution MRI.

Intracranial atherosclerosis (ICAS) is the leading cause of ischemic stroke in Asians and the recurrent rate remains high despite the optimal medical treatment. This study aimed to confirm that follow-up high-resolution magnetic resonance imaging (hrMRI) provided essential values in predicting subsequent cerebral ischemic events in patients with ICAS. Patients with moderate to severe stenosis in the middle cerebral artery (MCA) defined by magnetic resonance (MRA) or computed tomography angiography (CTA) were recruited from three centers retrospectively. Detailed plaque composition was analyzed on baseline and follow-up hrMRI. Multivariate Cox proportional hazards regression analysis was used to identify the key risk factors for predicting subsequent ischemic events. Among 152 patients, a total of 86 patients with MCA atherosclerotic stenosis underwent follow-up hrMRI exams and ipsilateral cerebral ischemic events occurred in 12 patients during a 1-year follow-up. Analyses showed the predictors of ischemic events were age (adjusted Hazard ratio (HR) = 0.942; 95% Confidence Interval (CI), [0.903, 0.983]; p = 0.006), progression of plaque burden (HR = 3.818; 95% CI [1.117, 13.051]; p = 0.033), vessel expansion (HR = 5.173; 95% CI [1.077, 24.838]; p = 0.040) and enhancement ratio progression (HR = 6.144; 95% CI [1.480, 25.511]; p = 0.012). The combined model achieved a concordance index of 0.804 (95% CI [0.658, 0.950]). Longitudinal hrMRI evaluation improved the accuracy in identifying higher-risk patients with intracranial atherosclerosis. Question Can longitude high-resolution magnetic resonance imaging (hrMRI) help clinicians observe intracranial plaque evolution? Findings Compared with the baseline exam, intracranial plaque evolution distinguished by follow-up hrMRI exam showed a higher accuracy in predicting subsequent ischemic events. Clinical relevance Longitudinal high-resolution magnetic resonance vessel wall imaging enables dynamic observation and evaluation of the changes in plaque characteristics among intracranial atherosclerosis patients. Atherosclerotic plaque evolution revealed by repeated exams can strengthen the risk stratification of patients with intracranial atherosclerosis.

Prophylactic phage aerosols for nosocomial infection control in an extracorporeal membrane oxygenation unit: A 4-year prospective study of temporospatially designed phage cocktails.

Phage-based decontamination has rarely been explored in real-world settings, particularly in the environments of patients undergoing extracorporeal membrane oxygenation (ECMO). This four-year prospective study aimed to evaluate the effectiveness of aerosolized phage cocktails tailored to combat target antibiotic-resistant species of Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. The decontamination procedure with phage aerosols was proactively implemented before the admission of ECMO patients based on a thorough analysis of phage typing results from bacterial species isolated from prospective patient areas during the preceding two months. The phage cocktail formulation design also accounted for phage resistance development, phage families, and plaque characteristics. Throughout the study, 85 ECMO patients were monitored, with the environments of 22 patients undergoing phage decontamination. Fifty phage cocktails were prepared to target the identified species. Respiratory infections were most common among ECMO patients, accounting for 71.4 %. The ECMO duration for patients infected with the targeted species was significantly longer than that for noninfected patients (P = 0.019), with peak infection incidence occurring between 3 and 7 days of ECMO treatment (67.1 per 1000 ECMO days). Notably, none of the patients in phage-treated environments contracted infections from the targeted species. However, the overall incidence of bacterial infections did not significantly correlate with phage decontamination efforts, as phages are effective only against their specific hosts. This study demonstrates the potential of prophylactic phage decontamination to prevent specific infections, aligning with One Health principles by offering a sustainable alternative to antibiotics, potentially significantly reducing antibiotic use.

Simulating atherosclerotic plaque mechanics using polyvinyl alcohol (PVA) cryogel artery phantoms, ultrasound imaging and inverse finite element analysis

The clinical decision to establish if a patient with carotid disease should undergo surgical intervention is primarily based on the percent stenosis. Whilst this applies for high-grade stenosed vessels (>70%), it falls short for other cases. Due to the heterogeneity of plaque tissue, probing the mechanics of the tissue would likely provide further insights into why some plaques are more prone to rupture. Mechanical characterization of such tissue is nontrivial, however, due to the difficulties in collecting fresh, intact plaque tissue and using physiologically relevant mechanical testing of such material. The use of polyvinyl alcohol (PVA) cryogel is thus highly convenient because of its acoustic properties and tunable mechanical properties.Methods.The aim of this study is to demonstrate the potential of PVA phantoms to simulate atherosclerotic features. In addition, a testing and simulation framework is developed for full PVA vessel material characterization using ring tensile testing and inflation testing combined with non-invasive ultrasound imaging and computational modeling.Results.Strain stiffening behavior was observed in PVA through ring tensile tests, particularly at high (n= 6) freeze-thaw cycles (FTCs). Inflation testing of bi-layered phantoms featuring lipid pool inclusions demonstrated high strains at shoulder regions. The application of an inverse finite element framework successfully recovered boundaries and determined the shear moduli for the PVA wall to lie within the range 27-53 kPa.Conclusion.The imaging-modeling framework presented facilitates the use and characterization of arterial mimicking phantoms to further explore plaque rupture. It also shows translational potential for non-invasive mechanical characterization of atherosclerotic plaques to improve the identification of clinically relevant metrics of plaque vulnerability.

The relationship between atherogenic index of plasma and plaque vulnerabilities: an optical coherence tomography study

BackgroundAtherogenic index of plasma (AIP) has been recommended as a marker of plasma atherogenicity. The impact of AIP on plaque characteristics is not fully understood.PurposeThe study investigates the relationship between AIP and coronary plaque features in patients with acute coronary syndrome (ACS).MethodsFrom January 2016 to June 2017 pre-intervention optical coherence tomography (OCT) was performed in 522 ACS patients. AIP was defined as the base 10 logarithm of the ratio of the concentrations of triglyceride to high-density lipoprotein cholesterol. Patients were divided into four groups according to AIP quartiles.ResultsA total of 332 patients were included for the analysis. The prevalence of thin-cap fibroatheroma (TCFA) (group I [lowest] 9.09% vs group II 16.5% vs group III 44.7% vs group IV [highest] 52.9%), macrophage accumulation (group I 18.2% vs group II 22.4% vs group III 31.8% vs group IV 47.1%), plaque rupture (group I 10.4% vs group II 14.1% vs group III 17.6% vs group IV 34.1%) and plaque erosion (group I 2.6% vs group II 2.4% vs group III 14.1% vs group IV 12.9%) were significantly different among AIP quartiles. Multivariate logistic regression revealed the risk of TCFA (odds ratio 11.130, 95% confidence interval 4.186–29.593, p < 0.001) and plaque rupture (OR 5.332, 95% CI 2.040–13.937, p < 0.001) increased in group IV compared to group I. Receiver operating characteristics curve showed the predictive value of AIP for TCFA and plaque rupture were 0.720 and 0.669 respectively.Conclusion(s)AIP is an independent predictor for vulnerable plaques beyond traditional factors. It can be integrated in clinical practice for risk stratification of ACS patients.Trial registrationAll patients gave their consent to participate in the study and the Ethics Committee of Beijing Anzhen Hospital, Capital Medical University approved it (2020047X).

The microbiome alterations of supragingival plaque among adolescents using clear aligners: a metagenomic sequencing analysis

BackgroundWhite spot lesions (WSLs) may develop in adolescents undergoing clear aligner (CA) therapy with poor oral hygiene. The specific effects of CAs on the microbial composition and functional characteristics of supragingival plaques remain unclear. The present study investigated the shift in the supragingival microbial community induced by CAs in adolescents through metagenomic technology.MethodsFifteen adolescents (12–15 years old) with Invisalign appliances were recruited. Supragingival plaque specimens were obtained twice, before treatment (T1) and three months after treatment (T2). All the bacterial plaque specimens were analyzed for microbial communities and functions using metagenomic analyses.ResultsA total of 2,840,242,722 reads disclosed 180 phyla, 3,975 genera, and 16,497 microbiome species. During the first three months, the microbial community was relatively stable. The genus level revealed a higher relative abundance of Capnocytophaga, Neisseria, and Arachnia in the T2 period. Furthermore, the functional analysis suggested that the relative abundances of folate biosynthesis, biotin metabolism and biofilm formation-vibrio cholerae were increased in the T2 period compared to the T1 period. Finally, virulence factor analysis demonstrated that the relative abundance of genes associated with type IV pili (VF0082) and polar flagella (VF0473) was higher in the T2 period than in the T1 period.ConclusionIn adolescents undergoing CA therapy with poor plaque control, caries progresses quickly within three months and noticeable WSLs develop on the tooth surface. Although the microbial community remained relatively steady and CA therapy did not cause significant changes in the overall functional gene composition in the first three months, virulence factors, including type IV pili and flagella, were more abundant and actively contributed to microorganism adhesion and biofilm formation.

Evaluating the influence of morphological features on the vulnerability of lipid-Rich plaques during stenting.

Lipid-rich atheromas are linked to plaque rupture in stented atherosclerotic arteries. While fibrous cap thickness is acknowledged as a critical indicator of vulnerability, it is likely that other morphological features also exert influence. However, detailed quantifications of their contributions and intertwined effects in stenting are lacking. Therefore, our goal is to assess the impact of plaque characteristics on the fibrous cap stress and elucidate their underlying mechanisms. We analyzed the stent deployment over a 3D patient-specific coronary artery reconstructed from intravascular optical coherence tomography (IVOCT) through finite element methods. Additionally, we performed sensitivity analysis on 78,000 distinct plaque geometries of two-dimensional arteries for verification. Results from the 3D patient-specific model indicate strong correlations between maximum fibrous cap stress and lipid arc (r=0.769), area stenosis (r=0.550), and lumen curvature (r=0.642). Plaques with lipid arcs > 60°, area stenosis > 75%, and lumen curvatures > 5 mm-1 are at increased rupture risk. While we observed a rise in stress with lipid core thickness, it was less representative than other features. Fibrous cap thickness showed a poor correlation, with the sensitivity analysis revealing its significance only when high stretches are induced by other features, likely due to its J-shaped stress-stretch response. Contrary to physiological pressure, the stent expansion generates unique vulnerable features as the stent load-transferring characteristics modify the plaque?s response. This study is expected to prompt further clinical investigations of other morphological features for predicting plaque rupture in stenting.

Intraplaque Hemorrhage and Plaque Ulceration Are More Likely in Patients with Symptomatic Mild-to-Moderate Carotid Artery Stenosis than in Symptomatic and Asymptomatic High-Grade Stenosis: A Retrospective Cohort Study.

To compare a cohort of symptomatic patients with mild- to moderate (<70%) carotid artery stenosis with those patients with high-grade (≥70%) carotid artery stenosis (symptomatic and asymptomatic) to assess for markers that places them at a higher risk for stroke. A propensity score matched cohort study design for all patients who underwent carotid revascularization between 2015 to 2024 was utilized to compare the high-grade (≥70%) symptomatic and asymptomatic carotid stenosis groups against the mild to moderate (<70%) symptomatic carotid stenosis group. Matched variables included age, sex, and atrial fibrillation. Vulnerable plaque was defined as the presence of intraplaque hemorrhage, ulceration, lipid necrotic core and inflammation on cross-sectional imaging. Images assessed included computed tomography angiography (CTA) and magnetic resonance angiography (MRA) with vessel wall imaging (VWI). Odds ratios (OR) were then calculated to assess for risk of vulnerable features present on cross-sectional imaging prior to carotid intervention. There were 58 patients in each cohort matched and analyzed. In our cohort of interest, there were fewer patients with diabetes and higher proportion of hyperlipidemia compared to those patients who were symptomatic with ≥70% carotid artery stenosis. Further, there were fewer patients with diabetes and none on dialysis compared to our asymptomatic high-grade stenosis group. The OR of presenting with vulnerable features in our mild- to moderate stenosis symptomatic group was 5.85 (95% CI 1.74-19.60, p=0.002) compared to the high-grade asymptomatic stenosis patients and 7.52 (95% CI 3.22-17.66, p<0.001) compared to the high-grade symptomatic stenosis patients. Additionally, the symptomatic <70% stenosis group had higher odds of intraplaque hemorrhage (OR 4.91, 95% CI 1.80-13.78, p<0.001) and ulcerated plaque (OR 8.93, 95% CI 2.47-32.82, p<0.001) compared to the asymptomatic ≥70% group, as well as increased odds of intraplaque hemorrhage (OR 4.14, 95% CI 1.59-10.74, p=0.002) and ulcerated plaque (OR 5.16, 95% CI 1.77-15.03, p=0.001) compared to the symptomatic ≥70% group. Composite outcomes of stroke, myocardial infarction and death were no different in 30-days and on mid-term follow-up. High-risk plaque features on cross-sectional imaging studies may justify a short-term more aggressive medical management and/or early intervention in patients with mild to moderate carotid artery stenosis, even when luminal narrowing alone would not typically warrant such measures. As such, use of advanced imaging to assess for plaque characteristics may allow for improved risk stratification and guide earlier management of this patient population.

Characterising high-risk plaque on cardiac CT.

Coronary computed tomography angiography (CCTA) is a well-established and reliable non-invasive imaging modality that provides a comprehensive assessment of coronary artery anatomy and luminal stenosis due to atherosclerosis. Owing to advances in CCTA software and technology, the composition and morphology of coronary plaque can be accurately evaluated. Adverse features which identify plaque as being high-risk or 'vulnerable' can provide a personalised cardiovascular risk assessment over and above stenosis severity. High-risk plaque features on CCTA include spotty calcification, low attenuation plaque, positive remodelling and the napkin ring sign. However, it can be challenging to characterise high-risk plaque accurately on CCTA, and as such, education and experience are required. In this pictorial essay, a comprehensive visual guide to high-risk plaque features on CCTA is provided, with clear examples and challenging cases that highlight common pitfalls. It is important for expert readers to properly identify these features given their association with adverse outcomes and potential future implications on intensive goal-directed medical therapy.