Characterization Of Plaque Morphology Research Articles

In Vivo Classification and Characterization of Carotid Atherosclerotic Lesions with Integrated 18F-FDG PET/MRI.

The aim of this study was to exploit integrated PET/MRI to simultaneously evaluate the morphological, component, and metabolic features of advanced atherosclerotic plaques and explore their incremental value. In this observational prospective cohort study, patients with advanced plaque in the carotid artery underwent 18F-FDG PET/MRI. Plaque morphological features were measured, and plaque component features were determined via MRI according to AHA lesion-types. Maximum standardized uptake values (SUVmax) and tissue to background ratio (TBR) on PET were calculated. Area under the receiver-operating characteristic curve (AUC) and net reclassification improvement (NRI) were used to compare the incremental contribution of FDG uptake when added to AHA lesion-types for symptomatic plaque classification. A total of 280 patients with advanced plaque in the carotid artery were recruited. A total of 402 plaques were confirmed, and 87 of 402 (21.6%) were symptomatic plaques. 18F-FDG PET/MRI was performed a mean of 38 days (range 1-90) after the symptom. Increased stenosis degree (61.5% vs. 50.0%, p < 0.001) and TBR (2.96 vs. 2.32, p < 0.001) were observed in symptomatic plaques compared with asymptomatic plaques. The performance of the combined model (AHA lesion type VI + stenosis degree + TBR) for predicting symptomatic plaques was the best among all models (AUC = 0.789). The improvement of the combined model (AHA lesion type VII + stenosis degree + TBR) over AHA lesion type VII model for predicting symptomatic plaques was the highest (AUC = 0.757/0.454, combined model/AHA lesion type VII model), and the NRI was 50.7%. Integrated PET/MRI could simultaneously evaluate the morphological component and inflammation features of advanced atherosclerotic plaques and provide supplementary optimization information over AHA lesion-types for identifying vulnerable plaques in atherosclerosis subjects to achieve further stratification of stroke risk.

Robustness and classification capabilities of MRI radiomic features in identifying carotid plaque vulnerability.

To assess how radiomic features may be combined with plaque morphological and compositional features identified by multi-contrast MRI to improve upon conventional risk assessment models in determining culprit carotid artery lesions. Fifty-five patients (mean age: 62.6; 35 males) with bilateral carotid stenosis who experienced transient ischaemic attack (TIA) or stroke were included from the CARE-II multi-centre carotid imaging trial (ClinicalTrials.gov Identifier: NCT02017756). They underwent MRI within 2 weeks of the event. Classification capability in distinguishing culprit lesions was assessed by machine learning. Repeatability and reproducibility of the results were investigated by assessing the robustness of the radiomic features. Radiomics combined with a relatively conventional plaque morphological and compositional metric-based model provided incremental value over a conventional model alone (area under curve [AUC], 0.819 ± 0.002 vs 0.689 ± 0.019, respectively, P = .014). The radiomic model alone also provided value over the conventional model (AUC, 0.805 ± 0.003 vs 0.689 ± 0.019, respectively, P = .031). T2-weighted imaging-based radiomic features had consistently higher robustness and classification capabilities compared with T1-weighted images. Higher-dimensional radiomic features outperformed first-order features. Grey Level Co-occurrence Matrix, Grey Level Dependence Matrix, and Grey Level Size Zone Matrix sub-types were particularly useful in identifying textures which could detect vulnerable lesions. The combination of MRI-based radiomic features and lesion morphological and compositional parameters provided added value to the reference-standard risk assessment for carotid atherosclerosis. This may improve future risk stratification for individuals at risk of major adverse ischaemic cerebrovascular events. The clinical relevance of this work is that it addresses the need for a more comprehensive method of risk assessment for patients at risk of ischaemic stroke, beyond conventional stenosis measurement. This paper shows that in the case of carotid stroke, high-dimensional radiomics features can improve classification capabilities compared with stenosis measurement alone.

Predictors of periprocedural myocardial infarction after left main bifurcation percutaneous coronary intervention guided by optical coherence tomography imaging: the PREVENT study

Abstract Background PMI is one of the most common and relevant complications that occur after PCI, but it is still a matter of controversy. This clinical entity has been frequently correlated to peculiar plaque morphological features by several intravascular imaging studies. PCI of the LM coronary artery is a complex procedural setting, where the prognostic value of PMI is higher. Intravascular ultrasound (IVUS) has a traditional predominance in the guidance of LM-PCI, but optical coherence tomography (OCT) outperforms IVUS in spatial resolution and has affirmed itself as a strong support to PCI. Purpose The aim of this study is to identify preprocedural and postprocedural optical coherence tomography (OCT) findings potentially related to periprocedural myocardial infarction (PMI) in patients undergoing percutaneous coronary intervention (PCI) for non-ostial left main (LM) bifurcation disease. Methods We retrospectively analyzed 76 patients who underwent OCT before and after LM-PCI. Definitions of OCT findings were derived from expert consensus documents and major OCT studies. PMI was defined in accordance with the Academic Research Consortium-2 (ARC-2) definition. Results The presence of TCFA was found to be an independent predictor of PMI, and coherently a significantly higher lipid core arc was observed in the PMI group. Mean stent area was the only post-PCI feature to result significantly higher in the PMI group. Conclusions We found the presence of TCFA at pre-PCI OCT was an independent predictor of PMI. A higher mean stent area at post-PCI OCT in patients who developed PMI may suggest that aggressive stent expansion could not always be the right choice in such a context.

Stress-Related Neural Activity Associates With Coronary Plaque Vulnerability and Subsequent Cardiovascular Events

BackgroundStress-related neural activity (SNA) assessed by amygdalar activity can predict cardiovascular events. However, its mechanistic linkage with plaque vulnerability is not fully elucidated. ObjectivesThe authors aimed to investigate the association of SNA with coronary plaque morphologic and inflammatory features as well as their ability in predicting major adverse cardiovascular events (MACE). MethodsA total of 299 patients with coronary artery disease (CAD) and without cancer underwent 18F-fluorodexoyglucose positron emission tomography/computed tomography (PET/CT) and available coronary computed tomographic angiography (CCTA) between January 1, 2013, and December 31, 2020. SNA and bone-marrow activity (BMA) were assessed with validated methods. Coronary inflammation (fat attenuation index [FAI]) and high-risk plaque (HRP) characteristics were assessed by CCTA. Relations between these features were analyzed. Relations between SNA and MACE were assessed with Cox models, log-rank tests, and mediation (path) analyses. ResultsSNA was significant correlated with BMA (r = 0.39; P < 0.001) and FAI (r = 0.49; P < 0.001). Patients with heightened SNA are more likely to have HRP (40.7% vs 23.5%; P = 0.002) and increase risk of MACE (17.2% vs 5.1%, adjusted HR 3.22; 95% CI: 1.31-7.93; P = 0.011). Mediation analysis suggested that higher SNA associates with MACE via a serial mechanism involving BMA, FAI, and HRP. ConclusionsSNA is significantly correlated with FAI and HRP in patients with CAD. Furthermore, such neural activity was associated with MACE, which was mediated in part by leukopoietic activity in the bone marrow, coronary inflammation, and plaque vulnerability.

Latent Coronary Plaque Morphology From Computed Tomography Angiography, Molecular Disease Activity on Positron Emission Tomography, and Clinical Outcomes.

Assessments of coronary disease activity with 18F-sodium fluoride positron emission tomography and radiomics-based precision coronary plaque phenotyping derived from coronary computed tomography angiography may enhance risk stratification in patients with coronary artery disease. We sought to investigate whether the prognostic information provided by these 2 approaches is complementary in the prediction of myocardial infarction. Patients with known coronary artery disease underwent coronary 18F-sodium fluoride positron emission tomography and coronary computed tomography angiography on a hybrid positron emission tomography/computed tomography scanner. Coronary 18F-NaF uptake was determined by the coronary microcalcification activity. We performed quantitative plaque analysis of coronary computed tomography angiography datasets and extracted 1103 radiomic features for each plaque. Using weighted correlation network analysis, we derived latent morphological features of coronary lesions which were aggregated to patient-level radiomics nomograms to predict myocardial infarction. Among 260 patients with established coronary artery disease (age, 65±9 years; 83% men), 179 (69%) participants showed increased coronary 18F-NaF activity (coronary microcalcification activity>0). Over 53 (40-59) months of follow-up, 18 patients had a myocardial infarction. Using weighted correlation network analysis, we derived 15 distinct eigen radiomic features representing latent morphological coronary plaque patterns in an unsupervised fashion. Following adjustments for calcified, noncalcified, and low-density noncalcified plaque volumes and 18F-NaF coronary microcalcification activity, 4 radiomic features remained independent predictors of myocardial infarction (hazard ratio, 1.46 [95% CI, 1.03-2.08]; P=0.03; hazard ratio, 1.62 [95% CI, 1.04-2.54]; P=0.02; hazard ratio, 1.49 [95% CI, 1.07-2.06]; P=0.01; and hazard ratio, 1.50 (95% CI, 1.05-2.13); P=0.02). In patients with established coronary artery disease, latent coronary plaque morphological features, quantitative plaque volumes, and disease activity on 18F-sodium fluoride positron emission tomography are additive predictors of myocardial infarction.

Qualitative and quantitative plaque enhancement on high-resolution vessel wall imaging predicts symptomatic intracranial atherosclerotic stenosis.

Intracranial atherosclerotic stenosis (ICAS) is a major cause of ischemic stroke (IS), and high-resolution vessel wall imaging (HR-VWI) can be used to assess the plaque characteristics of ICAS. This study aimed to qualitatively and quantitatively assess plaque enhancement of ICAS and to investigate the relationship between plaque enhancement, plaque morphological features, and IS. Data from adult patients with ICAS from April 2018 to July 2022 were retrospectively collected, and all patients underwent HR-VWI examination. Plaque enhancement was qualitatively and quantitatively assessed, and the plaque-to-pituitary stalk contrast ratio (CR) indicated the degree of plaque enhancement. Plaque characteristics, such as plaque burden and area, were quantitatively measured using HR-VWI. Furthermore, receiver-operating characteristic (ROC) analysis was performed to assess the ability of CR to discriminate plaque enhancement. The patients were divided into a symptomatic ICAS group and an asymptomatic ICAS group according to the clinical and imaging characteristics. Univariate and multivariate analyses were performed to investigate which factors were significantly associated with plaque enhancement and symptomatic ICAS. The plaque burden and CR were compared using linear regression. A total of 91 patients with ICAS were enrolled in this study. ICAS plaque burden was significantly associated with plaque enhancement (p = .037), and plaque burden was linearly positively correlated with CR (R = 0.357, p = .001). ROC analysis showed that the cutoff value of CR for plaque enhancement was 0.56 (specificity of 81.8%). Both plaque enhancement and plaque burden were significantly associated with symptomatic ICAS, and only plaque enhancement was an independent risk factor after multivariate analysis. Plaque burden was an independent risk factor for plaque enhancement and showed a linear positive correlation with CR. The cutoff value of CR for plaque enhancement was 0.56, and CR ≥ 0.56 was significantly associated with symptomatic ICAS, which was independently associated with plaque enhancement.

Development of an image classification pipeline for atherosclerotic plaques assessment using supervised machine learning

BackgroundDuring atherosclerosis, the narrowing of the arterial lumen is observed through the accumulation of bio compounds and the formation of plaque within artery walls. A non-linear optical imaging modality (NLOM), coherent anti-stokes Raman scattering (CARS) microscopy, can be used to image lipid-rich structures commonly found in atherosclerotic plaques. By matching the lipid’s molecular vibrational frequencies (CH bonds), it is possible to map the accumulation of lipid-rich structures without the need for exogenous labelling and/or processing of the samples. CARS allows for the visualization of the morphological features of plaque. In combination with supervised machine learning, CARS imaged morphological features can be used to characterize the progression of atherosclerotic plaques. ResultsBased on a set of label-free CARS images of atherosclerotic plaques (i.e. foam cell clusters) from a Watanabe heritable hyperlipidemic rabbit model, we developed an automated pipeline to classify atherosclerotic lesions based on their major morphological features. Our method uses image preprocessing to first improve the quality of the CARS-imaged plaque, followed by the segmentation of the plaque using Otsu thresholding, marker-controlled watershed, K-means segmentation and a novel independent foam cell thresholding segmentation. To define relevant morphological features, 27 quantitative features were extracted and further refined by a novel coefficient of variation feature refinement method in accordance with filter-type feature selection. Refined morphological features were supplied into three supervised machine learning algorithms; K-nearest neighbour, support vector machine and decision tree classifier. The classification pipeline showcased the ability to exploit relevant plaque morphological features to accurately classify 3 pre-defined stages of atherosclerosis: early fatty streak development (EFS) and advancing atheroma (AA) with a greater than 85% class accuracyConclusionsThrough the combination of CARS microscopy and computational methods, a powerful classification tool was developed to identify the progression of atherosclerotic plaque in an automated manner. Using a curated dataset, the classification pipeline demonstrated the ability to differentiate between EFS, EF and AA. Thus, presenting the opportunity to classify the onset of atherosclerosis at an earlier stage of development

The role of non-stenosing carotid artery plaques in embolic stroke of undetermined source, is it a silent offender? A review of literature.

Atherosclerotic cervical internal carotid artery disease is one of the major causes of ischemic stroke and transient ischemic attacks. The risk of stroke from mild to moderate stenoses (i.e. <50% stenosis) might be underestimated. There is increasing evidence that plaque morphological features reflect plaque instability that may harbor high risk for embolization. In this narrative review, we will review the literature on plaque features that predict vulnerability beyond the degree of stenosis, discuss the clinical association with stroke, and evaluate the evidence that these lesions serve as a source for embolic stroke of unknown source (ESUS). We performed a literature search using PubMed, EMBASE, and Web of Science. The terms "embolic stroke of undetermined source" and "plaque morphology" were used either alone or in combination with "non-flow limiting stenosis," "non-stenosing plaques," "high-risk plaque features" or "internal carotid artery plaque." Data on plaque morphology and ESUS were mainly taken from review articles, observational studies including retrospective cohort and cross-sectional studies, meta-analyses, and systematic reviews. Nonstenosing carotid artery plaques with high-risk features carry a remarkable risk for stroke occurrence and randomized clinical trials are warranted for further evaluation of using carotid artery stenting or carotid endarterectomy to mitigate the risk of stroke.

Quantification of patient-specific coronary material properties and their correlations with plaque morphological characteristics: An in vivo IVUS study

BackgroundA method using in vivo Cine IVUS and VH-IVUS data has been proposed to quantify material properties of coronary plaques. However, correlations between plaque morphological characteristics and mechanical properties have not been studied in vivo.Method: In vivo Cine IVUS and VH-IVUS data were acquired at 32 plaque cross-sections from 19 patients. Six morphological factors were extracted for each plaque. These samples were categorized into healthy vessel, fibrous plaque, lipid-rich plaque and calcified plaque for comparisons. Three-dimensional thin-slice models were constructed using VH-IVUS data to quantify in vivo plaque material properties following a finite element updating approach by matching Cine IVUS data. Effective Young's moduli were calculated to represent plaque stiffness for easy comparison. Spearman's rank correlation analysis was performed to identify correlations between plaque stiffness and morphological factor. Kruskal-Wallis test with Bonferroni correction was used to determine whether significant differences in plaque stiffness exist among four plaque groups. ResultOur results show that lumen circumference change has a significantly negative correlation with plaque stiffness (r = −0.7807, p = 0.0001). Plaque burden and calcification percent also had significant positive correlations with plaque stiffness (r = 0.5105, p < 0.0272 and r = 0.5312, p < 0.0193) respectively. Among the four categorized groups, calcified plaques had highest stiffness while healthy segments had the lowest. ConclusionThere is a close link between plaque morphological characteristics and mechanical properties in vivo. Plaque stiffness tends to be higher as coronary atherosclerosis advances, indicating the potential to assess plaque mechanical properties in vivo based on plaque compositions.

OCT imaging of a wide spectrum of culprit plaque morphology features in acute coronary syndromes

Background and Aims : Complication of atherosclerotic plaques is related to acute coronary syndromes (ACS). Optical coherence tomography (OCT) is an ideal imaging technique for assessing coronary plaque morphology. The aim of this study is to investigate the spectrum of coronary plaque morphology features in ACS, in order to better understand the mechanisms leading to plaque complications.

Application and interpretation of vessel wall magnetic resonance imaging for intracranial atherosclerosis: a narrative review

Background and ObjectiveAtherosclerosis is a systemic disease that occurs in the arteries, and it is the most important causative factor of ischemic stroke. Vessel wall magnetic resonance imaging (VWMRI) is one of the best non-invasive methods for displaying the vascular features of intracranial atherosclerosis. The main clinical applications of this technique include the exploration of the pathogenesis of intracranial atherosclerotic lesions, follow-up monitoring, and treatment prognosis judgment. As the demand for intracranial VWMRI increases in clinical practice, radiologists should be aware of the selection of imaging parameters and how they affect image quality, clinical indications, evaluation methods, and limitations in interpreting these images. Therefore, this review focused on describing how to perform and interpret VWMRI of intracranial atherosclerotic lesions.MethodsWe searched the studies on the application of VWMRI in the PubMed database from January 1, 2000 to March 31, 2022, and focused on the analysis of related studies on VWMRI in atherosclerotic lesions, including technical application, expert consensus, imaging characteristics, and the clinical significance of intracranial atherosclerotic lesions.Key Content and FindingsWe reviewed and summarized recent advances in the clinical application of VWMRI in atherosclerotic diseases. Currently accepted principles and expert consensus recommendations for intracranial VWMRI include high spatial resolution, multiplanar two and three-dimensional imaging, multiple tissue-weighted sequences, and blood and cerebrospinal fluid suppression. Understanding the characteristics of VWMRI of normal intracranial arteries is the basis for interpreting VWMRI of atherosclerotic lesions. Evaluating VWMRI imaging features of intracranial atherosclerotic lesions includes plaque morphological and enhancement characteristics. The evaluation of atherosclerotic plaque stability is the highlight of VWMRI.ConclusionsVWMRI has a wide range of clinical applications and can address important clinical questions and provide critical information for treatment decisions. VWMRI plays a key role in the comprehensive evaluation and prevention of intracranial atherosclerosis. However, intracranial VWMRI is still unable to obtain in vivo plaque pathological specimens for imaging—pathological comparison is the most significant limitation of this technique. Further technical improvements are expected to reduce acquisition time and may ultimately contribute to a better understanding of the underlying pathology of lesions on VWMRI.

Temporal assessment of lesion morphology on radiological images beyond lesion volumes-a proof-of-principle study.

To develop a general framework to assess temporal changes in lesion morphology on radiological images beyond volumetric changes and to test whether cocaine abstinence changes coronary plaque structure on serial coronary CT angiography (CTA). Chronic cocaine users with human immunodeficiency virus (HIV) infection were prospectively enrolled to undergo cash-based contingency management to achieve cocaine abstinence. Participants underwent coronary CTA at baseline and 6 and 12 months following recruitment. We segmented all coronary plaques and extracted 1103 radiomic features. We implemented weighted correlation network analysis to derive consensus eigen radiomic features (named as different colors) and used linear mixed models and mediation analysis to assess whether cocaine abstinence affects plaque morphology correcting for clinical variables and plaque volumes and whether serum biomarkers causally mediate these changes. Furthermore, we used Bayesian hidden Markov network changepoint analysis to assess the potential rewiring of the radiomic network. Sixty-nine PLWH (median age 55 IQR: 52-59 years, 19% female) completed the study, of whom 26 achieved total abstinence. Twenty consensus eigen radiomic features were derived. Cocaine abstinence significantly affected the pink and cyan eigen features (-0.04 CI: [-0.06; -0.02], p = 0.0009; 0.03 CI: [0.001; 0.04], p = 0.0017, respectively). These effects were mediated through changes in endothelin-1 levels. In abstinent individuals, we observed significant rewiring of the latent radiomic signature network. Using our proposed framework, we found 1 year of cocaine abstinence to significantly change specific latent coronary plaque morphological features and rewire the latent morphologic network above and beyond changes in plaque volumes and clinical characteristics. • We propose a general methodology to decompose the latent morphology of lesions on radiological images using a radiomics-based systems biology approach. • As a proof-of-principle, we show that 1 year of cocaine abstinence results in significant changes in specific latent coronary plaque morphologic features and rewiring of the latent morphologic network above and beyond changes in plaque volumes and clinical characteristics. • We found endothelin-1 levels to mediate these structural changes providing potential pathological pathways warranting further investigation.

Association of Plaque Location and Vessel Geometry Determined by Coronary Computed Tomographic Angiography With Future Acute Coronary Syndrome–Causing Culprit Lesions

Distinct plaque locations and vessel geometric features predispose to altered coronary flow hemodynamics. The association between these lesion-level characteristics assessed by coronary computed tomographic angiography (CCTA) and risk of future acute coronary syndrome (ACS) is unknown. To examine whether CCTA-derived adverse geometric characteristics (AGCs) of coronary lesions describing location and vessel geometry add to plaque morphology and burden for identifying culprit lesion precursors associated with future ACS. This substudy of ICONIC (Incident Coronary Syndromes Identified by Computed Tomography), a multicenter nested case-control cohort study, included patients with ACS and a culprit lesion precursor identified on baseline CCTA (n = 116) and propensity score-matched non-ACS controls (n = 116). Data were collected from July 20, 2012, to April 30, 2017, and analyzed from October 1, 2020, to October 31, 2021. Coronary lesions were evaluated for the following 3 AGCs: (1) distance from the coronary ostium to lesion; (2) location at vessel bifurcations; and (3) vessel tortuosity, defined as the presence of 1 bend of greater than 90° or 3 curves of 45° to 90° using a 3-point angle within the lesion. Association between lesion-level AGCs and risk of future ACS-causing culprit lesions. Of 548 lesions, 116 culprit lesion precursors were identified in 116 patients (80 [69.0%] men; mean [SD], age 62.7 [11.5] years). Compared with nonculprit lesions, culprit lesion precursors had a shorter distance from the ostium (median, 35.1 [IQR, 23.6-48.4] mm vs 44.5 [IQR, 28.2-70.8] mm), more frequently localized to bifurcations (85 [73.3%] vs 168 [38.9%]), and had more tortuous vessel segments (5 [4.3%] vs 6 [1.4%]; all P < .05). In multivariable Cox regression analysis, an increasing number of AGCs was associated with a greater risk of future culprit lesions (hazard ratio [HR] for 1 AGC, 2.90 [95% CI, 1.38-6.08]; P = .005; HR for ≥2 AGCs, 6.84 [95% CI, 3.33-14.04]; P < .001). Adverse geometric characteristics provided incremental discriminatory value for culprit lesion precursors when added to a model containing stenosis severity, adverse morphological plaque characteristics, and quantitative plaque characteristics (area under the curve, 0.766 [95% CI, 0.718-0.814] vs 0.733 [95% CI, 0.685-0.782]). In per-patient comparison, patients with ACS had a higher frequency of lesions with adverse plaque characteristics, AGCs, or both compared with control patients (≥2 adverse plaque characteristics, 70 [60.3%] vs 50 [43.1%]; ≥2 AGCs, 92 [79.3%] vs 60 [51.7%]; ≥2 of both, 37 [31.9%] vs 20 [17.2%]; all P < .05). These findings support the concept that CCTA-derived AGCs capturing lesion location and vessel geometry are associated with risk of future ACS-causing culprit lesions. Adverse geometric characteristics may provide additive prognostic information beyond plaque assessment in CCTA.

Abstract 13099: Correlation of Lipoprotein(a) Levels With Coronary Plaque Morphological Features and Vulnerability: An Optical Coherence Tomography Study

Introduction: High lipoprotein(a) level is a potential independent risk factor for coronary artery disease (CAD). However, the relationship between the Lp(a) value and the morphological characteristics of plaque defined by optical coherence tomography (OCT) has not been completely clarified so far. Meanwhile, no evidence has been raised for a clear cut-off value of Lp(a) for preventing the process of CAD. Hypothesis: Based on the biological properties of Lp(a), We assessed the hypothesis that the Lp(a) levels may relate to the vulnerable features of lipid plaque defined by OCT. Methods: 420 CAD patients who had undergone OCT scan to at least 1 main coronary vessel during 2013-2018 were enrolled. Patients were first stratified into 3 levels according to the values of Lp(a) at admission: Lp(a)&lt;30 mg/dl (Group A), 30-60 mg/dl(Group B), and &gt;60 mg/dl(Group C). After enrolled the cases with Lp(a) &gt;60mg/dl, we chose cases of the other 2 groups matching according to traditional risk factors of CAD to our current analysis. OCT pullbacks of the target vessels were collected and analyzed at every 0.4 mm by 2 independent observers blinded to the clinical data and angiographies with QIVUS software. Results: A total of 90 cases were enrolled into the current study, with 30 cases in each group. Lipid plaque in Group B and Group C had a thinner minimum fibrous cap thickness, wider maximum lipid arc, longer lipid length, and greater lipid index than Group A. The Lp(a) levels significantly correlated with lipid length (r=0.283), the maximum arc of lipid(r=0.293), lipid index(r=0.357), and inversely correlated with minimum fibrous cap thickness (r =-0.403). Multivariate analysis demonstrated that the Lp(a) level was independently associated with TCFA (odds ratio 1.035, 95% confidence interval 1.014-1.057). In addition, the ROC curve analysis results (AUC =0.694, p &lt; 0.001) indicated the Lp(a) is a good diagnostic indicator for detecting TCFA, and the optimal cut-off was 33.65 mg/dl. Conclusions: Our current study indicates that CAD patients with higher Lp(a) level(&gt;30 mg/dl) exhibited a higher prevalence of TCFA and had more other typical vulnerable characteristics defined by OCT. New Lp(a) lowering therapy could aim at a level of &lt; 33.65mg/dl for stabilizing coronary plaque.

The effects of plaque morphological characteristics on the post-stenotic flow in left main coronary artery bifurcation

Local post-stenotic hemodynamics has critical influence in the atherosclerotic plaque progression occurring in susceptible arterial sites, in particular the left main coronary artery (LMCA) bifurcation. Understanding the effects of plaque morphological characteristics: stenosis severity (SS), eccentricity index (EI) and lesion length (LL) on the post-stenotic flow behavior can significantly improve treatment planning. In order to investigate these effects, we have employed computational fluid dynamics (CFD) simulations in twenty computer-generated and five patient-specific LMCA models and the hemodynamic parameters: velocity, pressure (P), wall pressure gradient (WPG), wall shear stress (WSS), time averaged wall shear stress (TAWSS), oscillatory shear index (OSI), relative residence time (RRT) and helicity intensity (h2) were analyzed. Our results revealed that the effect of stenosis eccentricity varied significantly for different values of stenosis severity and lesion length. Regions with low WSS, low TAWSS and high RRT were more prominent in models having higher stenosis severity. For smaller lesion length, at low and moderate stenosis severity, surface area with low TAWSS and high RRT decreased with increasing eccentricity index, whereas for high stenosis severity models, low TAWSS region and average RRT values increased with eccentricity. However, for models with longer lesion length, regions with high OSI and RRT overall increased gradually with eccentricity. The helicity intensity (h2) of all models remained very low except at the most eccentric model with longer lesion length. The presence of very high helical flow in this model suggests the possibility of atheroprotective flow. It can be concluded that all plaque morphological characteristics covered under this investigation play an important role in plaque progression.

Morphological Plaque Characteristics and Clinical Outcomes in Patients With Acute Coronary Syndrome and a Cancer History

BackgroundAlthough patients with a cancer history have a 2 to 3 times higher risk for acute coronary syndrome (ACS), the morphological characteristics of ACS culprit plaque in those patients and their relations with clinical outcomes remain unknown.Methods and ResultsThis retrospective, multicenter, observational cohort study included consecutive patients with ACS who underwent optical coherence tomography‐guided emergent percutaneous coronary intervention. Patients were categorized into those without a cancer history, those with a cancer history, and those currently receiving cancer treatment. ACS culprit lesions were classified as plaque rupture, plaque erosion, or calcified nodule using optical coherence tomography. Plaque erosion frequency was significantly higher in culprit lesions of patients with current cancer and patients with cancer history than in those of patients without cancer history (56.3% versus 61.7% versus 36.5%). Calcified nodule incidence was significantly higher in patients without cancer history than in patients with current cancer and patients without cancer history (patients with current cancer: 12.4% versus patients without cancer history: 25.5% versus patients without cancer history: 12.6%, P<0.001). Cancer history was independently associated with nonplaque rupture (plaque erosion or calcified nodule) in ACS culprit lesions (odds ratio, 4.00; P<0.001). Cancer history was independently associated with major adverse cardiovascular events (hazard ratio [HR], 1.98; P=0.002). Nonplaque rupture in ACS culprit lesions was independently associated with major adverse cardiovascular events (HR, 1.60; P=0.011).ConclusionsPatients with a cancer history had significantly worse clinical outcomes after ACS than those without a cancer history. Those with a cancer history had significantly higher plaque erosion and calcified nodule incidences in the ACS culprit lesions, which might partly explain their worse clinical outcomes.RegistrationURL: www.umin.ac.jp/ctr/index.htm. Unique Identifier: UMIN000038442.

Relationship among clinical characteristics, morphological culprit plaque features, and long-term prognosis in patients with acute coronary syndrome.

Culprit lesions of acute coronary syndrome (ACS) could be classified as plaque rupture (PR), erosion, or calcified nodule (CN). We aimed to determine the relationship among clinical characteristics, morphological plaque features, and long-term prognosis in ACS. Patients with ACS, who underwent pre-intervention optical coherence tomography between April 2013 and July 2018 were retrospectively enrolled, and classified into the three groups based on the culprit lesion morphology. In the 436 patients enrolled, incidences of PR, erosion, and CN in ACS culprit lesions were 46.1, 39.9, and 14.0%, respectively. Plaque erosion was more frequent in men aged < 60 years and CN was more frequent in older adults in both sexes (≥ 80 years) (P < 0.001). Patients with CN had a higher incidence of hemodialysis treatment (P < 0.001) and diabetes (P = 0.003). Multivariate analysis revealed that ST elevation myocardial infarction (STEMI) (P = 0.049) and presence of thin-cap fibroatheroma (TCFA) at the culprit lesion were independently associated with PR; in younger patients (< 60 year), preserved left ventricular ejection fraction and lower incidence of TCFA were correlated with plaque erosion; and older age, non-STEMI, or unstable angina pectoris, higher serum brain natriuretic peptide levels, and lower incidence of TCFA were independently associated with CN. Multivariable analysis revealed that CN (odds ratio [OR] 1.990, P = 0.005), male sex (OR 2.012, P = 0.004), and older age (OR 1.036, P < 0.001) were independently associated with future adverse events during a median follow-up of 757 days. Different patient characteristics and morphological features were associated with the type of culprit lesion in patients with ACS.

Could Gender Impact on Immediate and Long-term Carotid Artery Stenting Outcome? Insight from an Italian Single Center Experience

Carotid artery stenting (CAS) has become a valid alternative to carotid endarterectomy in stroke prevention. However, female gender is still considered as an independent risk factor for CAS procedures, potentially limiting immediate and long-term benefits. Aim of present study was to evaluate gender differences in CAS submitted patients from an Italian high-volume center. a retrospective monocentric study has been conducted on 568 patients (366 males and 202 females), submitted to CAS, between January 2000 and December 2019. Besides gender sex, clinical anatomical, and procedural data were collected as possible factors determining the outcome, when associated to sex gender itself. Primary endpoint of this study consisted in evaluating the technical and procedural success ratio, and the incidence of major and minor stroke, transient ischemic attack, acute myocardial infarction (AMI) peri-procedurally and at medium and long term, between the male and the female population. Secondary endpoint of this study consisted in evaluating the percentage ratio of minor complications happening peri-procedurally in both genders. Male patients were more likely to be octogenarians, clinical history of coronary artery disease, and smokers, while diabetes was more frequent in female patients. Anatomical and plaque morphology features were not different between the two groups. Technical success was obtained in all but two patients (99,6%), while procedural success was 95% (538/566 patients). During the peri-procedural time, no major stroke, 16 minor strokes (2,81%, 2,45% males vs. 3,45% females, P= 0,48), and 11 transient ischemic attack (2,18% males vs. 1,48% females, P= 0,56) were recorded. At a medium follow-up 57 months, 32 stroke (8 major strokes, 24 minor strokes) episodes (5,6%, males 5,7% vs. females 5,4%, P= 0,88), 24 AMIs (4,2%, males 4,6% vs. females 3,46%, P= 0,5;), 13 restenosis (2,8%, males 2,4% vs. females 1,9%, P= 0,71) and 223 deaths (39,2%, males 34,9% vs. females 47%, P= 0,0048) were noted. Our results showed no differences in immediate, and long-term CAS outcomes between gender. Larger, prospective studies are required to assess the real importance and significance of gender in determining CAS procedures' benefit and outcome.

Contribution of Risk Factors to the Development of Coronary Atherosclerosis as Confirmed via Coronary CT Angiography: A Longitudinal Radiomics-based Study.

Background Various cardiovascular risk factors are thought to modify atherosclerosis in a similar fashion (ie, by increasing the magnitude of coronary artery disease [CAD]). However, coronary CT angiography allows precision phenotyping of plaque characteristics through use of radiomics. Purpose To assess whether different cardiovascular risk factors have distinctive contributions to the changes in plaque morphologic features over time. Materials and Methods Individuals with or without HIV infection and cocaine use and without cardiovascular symptoms underwent coronary CT angiography between May 2004 and August 2015. In the current HIPAA-compliant study, the effects of cocaine use, HIV infection, and atherosclerotic cardiovascular disease (ASCVD) risk on the temporal changes (mean ± standard deviation, 4.0 years ± 2.3 between CT angiographic examinations) in CAD structure were analyzed by using radiomic analysis. The changes in radiomic features were analyzed by using linear mixed models, with correction for factors that may change plaque structure: high-sensitivity C-reactive protein level, statin use, positive family history of CAD, and total plaque volume to account for any potential intrinsic correlation between volume and morphologic features. Clusters among significant radiomic features were identified by using hierarchical clustering. Bonferroni-corrected P values less than .00004 (.05 divided by 1276) were considered to indicate significant differences. Results Of 1429 participants, 300 with CAD confirmed at coronary CT angiography were randomly selected (mean age, 48 years ± 7; 210 men, 226 people infected with HIV, 174 people who use cocaine) and 1276 radiomic features were quantified for each plaque. Cocaine use was significantly associated with 23.7% (303 of 1276) of the radiomic features, HIV infection was significantly associated with 1.3% (17 of 1276), and elevated ASCVD risk was significantly associated with 8.2% (104 of 1276) (P < .00004 for all). Parameters associated with elevated ASCVD risk or cocaine use and HIV infection did not overlap. There were 13 clusters among the 409 parameters, eight of which were affected only by cocaine use and three of which were affected only by ASCVD risk. Conclusion Radiomics-based precision phenotyping indicated that conventional risk factors, cocaine use, and HIV infection each had different effects on CT angiographic morphologic changes in coronary atherosclerosis over 4 years. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Schoepf and Emrich in this issue.

Acute ischemic stroke versus transient ischemic attack: Differential plaque morphological features in symptomatic intracranial atherosclerotic lesions

Background and aimsIntracranial atherosclerotic disease (ICAD) is a major etiologic cause for acute ischemic stroke (AIS) and transient ischemic attack (TIA). The study was designed to investigate if differential morphological features exist in symptomatic atherosclerotic lesions between AIS and TIA patients. MethodsThe culprit plaques from 45 AIS patients and 42 TIA patients were analyzed for the degree of stenosis, vessel wall irregularity, normalized wall index (NWI), remodeling index, plaque-wall contrast ratio (CR), high signal intensity on T1-weighted images, plaque enhancement ratio and enhancement grade. These plaque features along with clinical characteristics were compared between AIS and TIA groups as well as between their stenosis degree-matched subgroups. ResultsOverall, grade 2 enhancement (OR 3.85, 95%CI 1.42–10.46, p = 0.006) and hyperlipidemia (OR 3.04, 95%CI 1.13–8.22, p = 0.025) were independent indicators for AIS, whereas high NWI (OR 1.47, 95%CI 0.76–2.86, p = 0.004) was associated with TIA. In the comparison between the subgroups with moderate (30%–69%) stenosis, high plaque-wall CR (OR 5.38, 95%CI 1.39–20.75, p = 0.008) was associated with AIS, whereas high NWI (OR 2.50, 95%CI 0.61–10.00, p = 0.006) was associated with TIA. ConclusionsOur study reveals differential morphological features in symptomatic ICAD lesions between AIS and TIA patients. Probing these features with MR vessel wall imaging may provide insights into the prognosis of patients with ICAD.