Plaque Characteristics Research Articles

Advances in Artificial Intelligence-Assisted Coronary Computed Tomographic Angiography for Atherosclerotic Plaque Characterization.

Coronary artery disease is a leading cause of death worldwide. Major adverse cardiac events are associated not only with coronary luminal stenosis but also with atherosclerotic plaque components. Coronary computed tomography angiography (CCTA) enables non-invasive evaluation of atherosclerotic plaque along the entire coronary tree. However, precise and efficient assessment of plaque features on CCTA is still a challenge for physicians in daily practice. Artificial intelligence (AI) refers to algorithms that can simulate intelligent human behavior to improve clinical work efficiency. Recently, cardiovascular imaging has seen remarkable advancements with the use of AI. AI-assisted CCTA has the potential to facilitate the clinical workflow, offer objective and repeatable quantitative results, accelerate the interpretation of reports, and guide subsequent treatment. Several AI algorithms have been developed to provide a comprehensive assessment of atherosclerotic plaques. This review serves to highlight the cutting-edge applications of AI-assisted CCTA in atherosclerosis plaque characterization, including detecting obstructive plaques, assessing plaque volumes and vulnerability, monitoring plaque progression, and providing risk assessment. Finally, this paper discusses the current problems and future directions for implementing AI in real-world clinical settings.

Investigating the relationship between intracranial atherosclerotic plaque remodelling and diabetes using high-resolution vessel wall imaging.

Intracranial atherosclerosis, a leading cause of stroke, involves arterial plaque formation. This study explores the link between plaque remodelling patterns and diabetes using high-resolution vessel wall imaging (HR-VWI). To investigate the factors of intracranial atherosclerotic remodelling patterns and the relationship between intracranial atherosclerotic remodelling and diabetes mellitus using HR-VWI. Ninety-four patients diagnosed with middle cerebral artery or basilar artery atherosclerosis were enrolled. Their basic clinical data were collected, and HR-VWI was performed. The vascular area at the plaque (VAMLN) and normal reference vessel (VAreference) were delineated and measured using image postprocessing software, and the Remodelling index (RI) was calculated. According to the value of the RI, the patients were divided into a positive remodelling (PR) group, intermediate remodelling (IR) group, negative remodelling (NR) group, PR group and non-PR (N-PR) group. The PR group exhibited a higher prevalence of diabetes and serum cholesterol levels than the IR and NR groups [45.2%, 4.54 (4.16, 5.93) vs 25%, 4.80 ± 1.22 and 16.4%, 4.14 (3.53, 4.75), respectively, P < 0.05]. The diabetes incidence was also significantly greater in the PR group than in the N-PR group (45.2% vs 17.5%, P < 0.05). Furthermore, the PR group displayed elevated serum triglyceride and cholesterol levels compared to the N-PR group [1.64 (1.23, 2.33) and 4.54 (4.16, 5.93) vs 4.54 (4.16, 5.93) and 4.24 (3.53, 4.89), P < 0.05]. Logistic regression analysis revealed diabetes mellitus as an independent influencing factor in plaque-PR [odds ratio (95% confidence interval): 3.718 (1.207-11.454), P < 0.05]. HR-VWI can clearly show the morphology and signal characteristics of intracranial vascular walls and plaques. Intracranial atherosclerotic plaques in diabetic patients are more likely to show PR, suggesting poor plaque stability and a greater risk of stroke.

Comprehensive biomechanical and anatomical atherosclerotic plaque metrics predict major adverse cardiovascular events: A new tool for clinical decision making

Background and aimsAnatomical imaging alone of coronary atherosclerotic plaques is insufficient to identify risk of future adverse events and guide management of non-culprit lesions. Low endothelial shear stress (ESS) and high plaque structural stress (PSS) are associated with events, but individually their predictive value is insufficient for risk prediction. We determined whether combining multiple complementary, biomechanical and anatomical plaque characteristics improves outcome prediction sufficiently to inform clinical decision-making. MethodsWe examined baseline ESS, ESS gradient (ESSG), PSS, and PSS heterogeneity index (HI), and plaque burden in 22 lesions that developed subsequent events and 64 control lesions that remained quiescent from the PROSPECT study. Results86 fibroatheromas were analysed from 67 patients. Lesions with events showed higher PSS HI (0.32 vs. 0.24, p<0.001), lower local ESS (0.56Pa vs. 0.91Pa, p = 0.007), and higher ESSG (3.82 Pa/mm vs. 1.96 Pa/mm, p = 0.007), while high PSS HI (hazard ratio [HR] 3.9, p = 0.006), high ESSG (HR 3.4, p = 0.007) and plaque burden>70 % (HR 2.6, p = 0.02) were independent outcome predictors in multivariate analysis. Combining low ESS, high ESSG, and high PSS HI gave both high positive predictive value (80 %), which increased further combined with plaque burden>70 %, and negative predictive value (81.6 %). Low ESS, high ESSG, and high PSS HI co-localised spatially within 1 mm in lesions with events, and importantly, this cluster was distant from the minimum lumen area site. ConclusionsCombining complementary biomechanical and anatomical metrics significantly improves risk-stratification of individual coronary lesions. If confirmed from larger prospective studies, our results may inform targeted revascularisation vs. conservative management strategies.

Protruding Aortic Plaque and Coronary Plaque Vulnerability.

Protruding aortic plaque is known to be associated with an increased risk for future cardiac and cerebrovascular events. However, the relationship between protruding aortic plaque and coronary plaque characteristics has not been systematically investigated. A total of 615 patients who underwent computed tomography angiography, and preintervention optical coherence tomography imaging were included. Coronary plaque characteristics were compared to evaluate coronary plaque vulnerability in patients with protruding aortic plaque on computed tomography angiography. 615 patients, the 186 (30.2%) patients with protruding aortic plaque were older and had more comorbidities such as hypertension, chronic kidney disease, and a prior myocardial infarction than those without. They also had a higher prevalence of coronary plaques with vulnerable features such as thin-cap fibroatheroma (85 [45.7%] versus 120 [28.0%], P<0.001), lipid-rich plaque (165 [88.7%] versus 346 [80.7%], P=0.014), macrophages (147 [79.0%] versus 294 [68.5%], P=0.008), layered plaque (117 [62.9%] versus 213 [49.7%], P=0.002), and plaque rupture (96 [51.6%] versus 111 [25.9%], P<0.001). Patients with protruding aortic plaque experienced more major adverse cardiac and cerebrovascular events, including all-cause mortality, nonfatal acute coronary syndromes, and stroke (27 [14.7%] versus 21 [4.9%], P<0.001; 8 [4.3%] versus 1 [0.2%], P<0.001; 5 [2.7%] versus 3 [0.7%], P=0.030; and 5 [2.7%] versus 2 [0.5%], P=0.013, respectively). The current study demonstrates that patients with protruding aortic plaque have more features of coronary plaque vulnerability and are at increased risk of future adverse events.

Advanced CT measures of coronary artery disease with intermediate stenosis in patients with severe aortic valve stenosis

BackgroundCoronary artery disease (CAD) and severe aortic valve stenosis (AS) frequently coexist. While pre-transcatheter aortic valve replacement (TAVR) computed tomography angiography (CTA) allows to rule out obstructive CAD, interpreting hemodynamic significance of intermediate stenoses is challenging. This study investigates the incremental value of CT-derived fractional flow reserve (CT-FFR), quantitative coronary plaque characteristics (e.g., stenosis degree, plaque volume, and composition), and peri-coronary adipose tissue (PCAT) density to detect hemodynamically significant lesions among those with AS and CAD.Materials and methodsWe included patients with severe AS and intermediate coronary lesions (20–80% diameter stenosis) who underwent pre-TAVR CTA and invasive coronary angiogram (ICA) with resting full-cycle ratio (RFR) assessment between 08/16 and 04/22. CTA image analysis included assessment of CT-FFR, quantitative coronary plaque analysis, and PCAT density. Coronary lesions with RFR ≤ 0.89 indicated hemodynamic significance as reference standard.ResultsOverall, 87 patients (age 77.9 ± 7.4 years, 38% female) with 95 intermediate coronary artery lesions were included. CT-FFR showed good discriminatory capacity (area under receiver operator curve (AUC) = 0.89, 95% confidence interval (CI) 0.81–0.96, p < 0.001) to identify hemodynamically significant lesions, superior to anatomical assessment, plaque morphology, and PCAT density. Plaque composition and PCAT density did not differ between lesions with and without hemodynamic significance. Univariable and multivariable analyses revealed CT-FFR as the only predictor for functionally significant lesions (odds ratio 1.28 (95% CI 1.17–1.43), p < 0.001). Overall, CT-FFR ≤ 0.80 showed diagnostic accuracy, sensitivity, and specificity of 88.4% (95%CI 80.2–94.1), 78.5% (95%CI 63.2–89.7), and 96.2% (95%CI 87.0–99.5), respectively.ConclusionCT-FFR was superior to CT anatomical, plaque morphology, and PCAT assessment to detect functionally significant stenoses in patients with severe AS.Clinical relevance statementCT-derived fractional flow reserve in patients with severe aortic valve stenosis may be a useful tool for non-invasive hemodynamic assessment of intermediate coronary lesions, while CT anatomical, plaque morphology, and peri-coronary adipose tissue assessment have no incremental or additional benefit. These findings might help to reduce pre-transcatheter aortic valve replacement invasive coronary angiogram.Key Points• Interpreting the hemodynamic significance of intermediate coronary stenoses is challenging in pre-transcatheter aortic valve replacement CT.• CT-derived fractional flow reserve (CT-FFR) has a good discriminatory capacity in the identification of hemodynamically significant coronary lesions.• CT-derived anatomical, plaque morphology, and peri-coronary adipose tissue assessment did not improve the diagnostic capability of CT-FFR in the hemodynamic assessment of intermediate coronary stenoses.

Thin Calcification Predicts Lipid Component in Carotid Plaque—Relationship Between Lipid Distribution and Thin Calcification

BackgroundAccurately evaluating plaque characteristics is essential because lesions with lipid-rich plaque put patients at risk of thromboembolic complications from carotid artery stenting (CAS). Near-infrared spectroscopy (NIRS) is a diagnostic imaging modality that identifies lipid components from the near-infrared absorption pattern, but does not reveal the distribution of calcification. The purpose of this study was to investigate the calcification characteristics of unstable carotid plaques, focusing on relationships between the calcification characteristics revealed by computed tomography angiography (CTA) and the lipid core distribution derived from NIRS. MethodsParticipants in this retrospective analysis comprised 35 patients (29 men, 6 women; mean age, 76.0 years; range, 52–89 years) who underwent CAS in our institute between January 2021 and December 2022. We evaluated the thickness and length of carotid calcifications at the minimal lumen level from preoperative CTA and analyzed the relationship with maximal lipid core burden index (max-LCBI) from NIRS. ResultsStrong, negative linear correlations were observed between the thickness of calcification and max-LCBI at Area (any segment in a target lesion) (r=-0.795, p<0.001), max-LCBI at minimal lumen area (MLA) (r=-0.795, p<0.001) and LCBI at Lesion (rate of LCBI in entire plaque lesion) (r=-0.788, p<0.001), respectively. Significant negative linear correlations were observed between distribution of calcification length and max-LCBI at Area (r=-0.429, p=0.01), max-LCBI at MLA (r=-0.373, p=0.027) and LCBI at Lesion (r=-0.443, p=0.008). ConclusionsThin and ubiquitous carotid calcification was associated with LCBI values derived from NIRS indicative of carotid lipid plaque distribution, implying the possibility of predicting lesion instability.

Atherosclerotic plaque stabilization and regression: a review of clinical evidence.

Atherosclerotic plaque results from a complex interplay between lipid deposition, inflammatory changes, cell migration and arterial wall injury. Over the past two decades, clinical trials utilizing invasive arterial imaging modalities, such as intravascular ultrasonography, have shown that reducing levels of atherogenic lipoproteins, mainly serum LDL-cholesterol (LDL-C), to very low levels can safely reduce overall atherosclerotic plaque burden and favourably modify plaque composition. Classically, this outcome has been achieved with intensive statin therapy. Since 2016, newer and potent lipid-lowering strategies, such as proprotein convertase subtilisin-kexin type 9 inhibition, have shown incremental effects on plaque regression and risk of clinical events. Despite maximal reduction in plasma LDL-C levels, considerable residual cardiovascular risk remains in some patients. Therefore, there is a need to study therapeutic approaches that address residual risk beyond LDL-C reduction to promote plaque stabilization or regression. Contemporary imaging modalities, such as coronary computed tomography angiography, enable non-invasive assessment of the overall atherosclerotic plaque burden as well as of certain local plaque characteristics. This technology could allow further study of plaque stabilization and regression using novel therapeutic approaches. Non-invasive plaque assessment might also offer the potential to guide personalized management strategies if validated for this purpose.

Modern approaches to ultrasonographic assessment of carotid plaque in terms of its potential instability.

Aim: To identify potentially adverse characteristics of atherosclerotic carotid plaque in terms of stroke risk. Materials and Methods: The study is based on the analysis of US data obtained from 96 patients aged 47 to 84 years diagnosed with carotid stenosis. The patients were divided into 2 groups depending on the presence or absence of ischemic events. Examination methods: clinical, duplex US, brain MRI, statistical. In addition to the standard US criteria for the evaluation of carotid stenoses, superb microvascular imaging (SMI) and shear wave elastography (SWE) are used. Results: Statistically significant association of the following characteristics of plaques with the presence of ipsilateral ischemia focus was established: maximum thickness (p = 0,04), presence of microvascularization according to SMI data (p = 0,02), degree of carotid stenosis (statistically significant in the right carotid circulation [p = 0,04]), stiffness of the plaque according to SWE data (significantly in the right carotid circulation [p = 0,001]), type of plaque echogenicity according to Gray-Weale-Geroulakos classification (on the right carotid artery; p = 0,04). Conclusions: The presence of microvascularization according to SMI data and the low stiffness of the plaque according to SWE data can characterize the potential instability of the carotid plaque. These criteria should be added to the traditional US assessment of carotid plaques.

Carotid plaque characteristics in the CREST-2 trial

BackgroundThe modest stroke prevention from surgery for asymptomatic carotid disease has prompted a search for predictors that may improve risk stratification beyond luminal stenosis. Plaque disruption and atheroembolization are associated with unique anatomical and histological changes. The Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial (CREST-2) collects information on duplex ultrasound (DUS) plaque biomarkers with the goal of evaluating their relationship to the periprocedural and long-term risks of stroke. In this study, we examine the reliability with which carotid plaque features can be measured from DUS images, and report baseline carotid DUS-derived stenosis and plaque features using semiautomated digital image analysis of patients enrolled in CREST-2. MethodsWe studied the first 503 patients in CREST-2. Patients underwent standardized carotid DUS evaluation pre-enrollment. B-Mode images were scaled linearly to normalize brightness. Plaques were outlined manually. Dedicated software automatically measured the longitudinal sectional area (mm2), grayscale median (GSM), Gray-Weale classification, and tissue composition (mm2) of intraplaque hemorrhage (IPH), lipid, fibrous tissue, muscle, and calcium. We present the mean, standard deviation, median, interquartile range, minimum and maximum range, and proportions of carotid peak systolic velocities (PSVs) and plaque morphological features. We tested for autocorrelation among plaque features and computed the proportion of potentially unstable plaques in the cohort. Reliability of the image analysis techniques was tested in 100 patients using Bland-Altman plots and intraclass and interclass correlation coefficients. ResultsMost patients were male (58.4%), older (mean age of 69.3 years), White (87.5%), and had a PSV of ≥230 cm/s (98.6%); the 1.4% with a PSV of <230 cm/s were enrolled based on catheter angiography. Plaques in this study were large; the mean longitudinal sectional area was 62 ± 37 mm2 (range, 6.2–256.5 mm2). The mean GSM was 58 ± 30 (unitless) (range, 0–168) and Gray-Weale classification was 3.5 ± 0.9 (range, 1–5). The mean areas of tissue types were IPH 5.3 ± 8.9 mm2, lipid 9.3 ± 8.6 mm2, fibrous tissue 10 ± 10 mm2, muscle 17 ± 12 mm2, and calcium 1.6 ± 4.1 mm2. The PSV of patients showed poor correlation with plaque features. The proportion of plaques with a GSM of ≤35 was 22.8%, IPH of ≥5 mm2 was 30.0%, and a lipid-rich necrotic core of ≥40% was 3.0% of the cohort. Plaque measurements could be performed with high reliability with good interobserver and intraobserver correlations. ConclusionsSite-generated, core laboratory-interpreted ultrasound examination provides a reliable way of characterizing carotid plaque morphological features across studies performed at many CREST-2 sites. The initial cohort of patients randomized in CREST-2 had heterogeneity of plaque features despite causing high-grade stenosis. Completion of the trial will provide an opportunity to assess whether plaque heterogeneity interacts with response to revascularization and medical management.

Identification of symptomatic carotid artery plaque: a predictive model combining angiography with optical coherence tomography.

Symptomatic carotid artery disease is indicative of an elevated likelihood of experiencing a subsequent stroke, with the morphology of plaque and its specific features being closely linked to the risk of stroke occurrence. Our study based on the characteristics of carotid plaque assessed by optical coherence tomography (OCT), the plaque morphology evaluated by digital subtraction angiography (DSA) and clinical laboratory indicators were combined, develop a combined predictive model to identify symptomatic carotid plaque. Patients diagnosed with carotid atherosclerotic stenosis who underwent whole-brain DSA and OCT examination at the Affiliated Hospital of Jining Medical University from January 2021 to November 2023 were evaluated. Clinical features, as well as DSA and OCT plaque characteristics, were analyzed for differences between symptomatic and asymptomatic cohorts. An analysis of logistic regression was carried out to identify factors associated with the presence of symptomatic carotid plaque. A multivariate binary logistic regression equation was established with the odds ratio (OR) serving as the risk assessment parameter. The receiver operating characteristic curve was utilized to assess the combined predictive model and independent influencing factors. A total of 52 patients were included in the study (symptomatic: 44.2%, asymptomatic: 55.8%). Symptomatic carotid stenosis was significantly linked to four main factors: low-density lipoprotein-cholesterol >3.36 mmol/L [OR, 6.400; 95% confidence interval (CI), 1.067-38.402; p = 0.042], irregular plaque (OR, 6.054; 95% CI, 1.016-36.083; p = 0.048), ruptured plaque (OR, 6.077; 95% CI, 1.046-35.298; p = 0.048), and thrombus (OR, 6.773; 95% CI, 1.194-38.433; p = 0.044). The combined predictive model generated using four indicators showed good discrimination (Area Under Curve, 0.924; 95% CI, 0.815-0. 979). The p value was <0.05 with 78.26% sensitivity and 93.10% specificity. OCT is valuable in evaluating the plaque characteristics of carotid atherosclerotic stenosis. The combined predictive model comprising low-density lipoprotein-cholesterol >3.36 mmol/L, irregular plaque, ruptured plaque, and thrombus could help in the detection of symptomatic carotid plaque. Further research conducted on additional independent cohorts is necessary to confirm the clinical significance of the predictive model for symptomatic carotid plaque.

Comparison of Carotid Ultrasound Parameters in Patients with Rheumatoid Arthritis and Control Subjects: A Cross-sectional Study

Introduction: Rheumatoid Arthritis (RA) is considered one of the risk factors for Cardiovascular Disease (CVD). Carotid ultrasound is used to assess the extent of subclinical atherosclerosis in patients with RA. Very few studies have evaluated all carotid ultrasound findings, such as Carotid Intima-media Thickness (CIMT), carotid diameters like Luminal Diameter (LD) and Interadventitial Diameter (IAD), and plaque characteristics in patients with RA. Aim: To assess and compare the various carotid parameters in RA patients with controls and also to evaluate their association with age and duration of onset of the disease. Materials and Methods: A single-centre cross-sectional study was conducted at the Department of Radiology, GCS Medical College and Hospital, Ahmedabad, Gujarat, India, involving 40 patients with RA (Group-RA) and 40 controls (Group-C). Patients were further divided into three age subgroups. Carotid ultrasound parameters like CIMT, LD, IAD, and plaque were evaluated in both groups. Continuous variables were analysed using the t-test, and categorical data were analysed using the Chi-squared test. A p-value of &lt; 0.05 was considered statistically significant. Results: Age- and sex-matched controls were included with 28 females and 12 males in both the study groups. The mean LD and IAD were significantly higher in the RA group than in controls (Mean LD- 5.88±0.97 mm vs 5.26±1.08 mm with p=0.009; Mean IAD- 6.85±0.89 mm vs 6.30±0.87 mm with p=0.006). The mean CIMT was higher in the RA group but not statistically significant (0.57±0.13 mm vs 0.54±0.12 mm with p=0.256). Further subgroup analysis showed that all carotid parameters were statistically significant in the 31-60 years age group as compared to 18-30 years and 61-80 years subgroups. The effect of the duration of the disease (&gt;5 years) on the carotid parameters was also significantly higher in the 30-60 age group (p&lt;0.001). Conclusion: The present study showed that various carotid ultrasound parameters can be used as a screening tool in the follow-up of RA patients to detect early changes in atherosclerosis, with LD and IAD having superior predictive capability. The study further showed that carotid ultrasound parameters have a better predictive value in the 31-60 years age group.

The prevalence of extracranial carotid atherosclerosis detected via ultrasound imaging: A single-centre study in Jeddah, Saudi Arabia.

To assess the prevalence of carotid atherosclerosis in Jeddah, Saudi Arabia. Data on patients who underwent carotid ultrasound examinations between 2017-2021 were collected retrospectively from the archive of King Abdulaziz University Hospital, Jeddah, Saudi Arabia. Patient characteristics, blood lipid profiles, and plaque features were extracted from the medical records and ultrasound images. Descriptive data were presented as percentages. In total, 1334 patients were reviewed. Of these, 13.5% had carotid plaques and were included in the analysis. The mean patient age was 69.8±10.4 years, and 76.1% were men. The prevalence of hypertension was 62.7% and the prevalence of diabetes was 50%, and 7.2% of patients were smokers. Regarding blood lipid profiles, 6.5% of patients had high total cholesterol, 15.1% had high triglyceride levels, and 10.7% had high low-density lipoprotein levels. The median (interquartile range) stenosis was 34.4 (17.2) %, while the median plaque length was 5 (6) mm and thickness was 3 (1) mm. The median carotid intima-media thickness was 1 (0.3) mm. Regarding plaque distribution, 62.7% of plaques were in the carotid bulb. Additionally, 28.3% was in the internal carotid artery, 6.1% was in the common carotid artery, and 2.7% was in the external carotid artery. The prevalence of carotid atherosclerosis among patients in Jeddah, Saudi Arabia, was low. A high prevalence of hypertension and diabetes (≥50%) was observed among the patients. Multicenter studies involving larger Saudi samples are warranted to explore carotid atherosclerosis risk factors.

Role of intravascular ultrasound and optical coherence tomography in intracoronary imaging for coronary artery disease: a systematic review.

Coronary angiography has long been the standard for coronary imaging, but it has limitations in assessing vessel wall anatomy and guiding percutaneous coronary intervention (PCI). Intracoronary imaging techniques like intravascular ultrasound (IVUS) and optical coherence tomography (OCT) can overcome these limitations. IVUS uses ultrasound and OCT uses near-infrared light to visualize coronary pathology in unique ways due to differences in temporal and spatial resolution. These techniques have evolved to offer clinical utility in plaque characterization and vessel assessment during PCI. Meta-analyses and adjusted observational studies suggest that both IVUS and OCT-guided PCI correlate with reduced cardiovascular risks compared to angiographic guidance alone. While IVUS demonstrates consistent clinical outcome benefits, OCT evidence is less robust. IVUS has progressed from early motion detection to high-resolution systems, with smaller compatible catheters. OCT utilizes near infrared light to achieve unparalleled resolutions, but requires temporary blood clearance for optimal imaging. Enhanced visualization and guidance make IVUS and OCT well-suited for higher risk PCI in patients with diabetes and chronic kidney disease by allowing detailed visualization of complex lesions and ensuring optimal stent deployment and positioning in PCI for patients with type 2 diabetes and chronic kidney disease, improving outcomes. IVUS and recent advancements in zero- and low-contrast OCT techniques can reduce nephrotoxic contrast exposure, thus helping to minimize PCI complications in these high-risk patient groups. IVUS and OCT provide valuable insights into coronary pathophysiology and guide interventions precisely compared to angiography alone. Both have comparable clinical outcomes, emphasizing the need for tailored imaging choices based on clinical scenarios. Continued refinement and integration of intravascular imaging will likely play a pivotal role in optimizing coronary interventions and outcomes. This systematic review aims to delve into the nuances of IVUS and OCT, highlighting their strengths and limitations as PCI adjuncts.

Age-related Pancoronary Characteristics in Patients with ST-segment Elevation Myocardial Infarction

Background: Age-related vulnerable characteristics of pancoronary plaques in patients with ST-segment elevation myocardial infarction (STEMI) have not been systemically evaluated by optical coherence tomography (OCT). Therefore, we sought to explore the discrepancies in pancoronary characteristics between younger and older patients with STEMI through OCT. Methods: This retrospective single-center study included 588 patients who had STEMI and underwent three-vessel OCT through emergency percutaneous coronary intervention between October 2016 and September 2018. With a median age of 56 years as a cutoff, the patients were divided into a younger group (≤56 years, n = 298) and an older group (&gt;56 years, n = 290). Results: A total of 795 non-culprit plaques were found in 298 of the younger patients, whereas 858 non-culprit plaques were identified in 290 of the older patients. Fewer high-risk OCT plaques (15.8% vs. 23.1%; P = 0.025), as well as other structures (cholesterol crystals, P = 0.001; microchannels, P = 0.032; calcifications, P &lt; 0.001; spotty calcifications, P &lt; 0.001; large calcifications, P &lt; 0.001; and thrombi, P = 0.001) were identified in younger patients than older patients, at the patient level. In addition, pancoronary vulnerability in younger patients was independently predicted by culprit plaque rupture {CLIMA-defined high-risk plaques (odds ratio [OR]: 3.179; 95% CI: 1.501 to 6.733; P = 0.003), non-culprit rupture (OR: 3.802; 95% CI: 1.604 to 9.014; P = 0.002), non-culprit thin-cap fibroatheroma (OR: 3.536; 95% CI: 2.051 to 6.094; P &lt; 0.001)}, hypertension (OR: 1.920; 95% CI: 1.099 to 3.355; P = 0.022), and total cholesterol (OR: 1.094; 95% CI: 1.002 to 1.195; P = 0.045). In older patients with STEMI, the predictor was male sex (OR: 3.031; 95% CI: 1.352 to 6.795; P = 0.007). Conclusions: Among patients with STEMI, younger patients had limited vulnerable plaque characteristics, and pancoronary vulnerability was associated with culprit plaque rupture, hypertension, and total cholesterol. In contrast, older patients had greater pancoronary vulnerability with the single predictor of male sex, thus suggesting that traditional risk factors have limited applicability in predicting pancoronary vulnerability in older patients.

ПЕРСПЕКТИВЫ АТОМНО-СИЛОВОЙ МИКРОСКОПИИ В ИЗУЧЕНИИ ПАТОЛОГИЧЕСКИХ ПРОЦЕССОВ У ПАЦИЕНТОВ КАРДИОЛОГИЧЕСКОГО ПРОФИЛЯ

Numerous studies have been devoted to the study of fundamental cellular processes all over the world. The development of new research methods with high resolution has made it possible to study pathological processes at the micro and nanoscale. Atomic force microscopy is one of the promising methods for obtaining qualitative and quantitative information about pathological conditions, based on the analysis of surface topography (dimensions, roughness) and local mechanical properties (modulus of elasticity, adhesion strength, tribological properties) of structural elements of cells and tissues. The article briefly describes the principle of operation of the method and the possibilities of its application in various fields of medicine (therapy, oncology, ophthalmology, transfusiology, dentistry, etc.). The role of shaped blood elements (erythrocytes, platelets) in the pathogenesis of cardiological diseases is presented in detail. The possibilities of the method in studying the characteristics of atherosclerotic plaque in coronary arteries at different stages of atherogenesis are considered.

A clinical-radiomics combined model based on carotid atherosclerotic plaque for prediction of ischemic stroke.

To accurately predict the risk of ischemic stroke, we established a radiomics model of carotid atherosclerotic plaque-based high-resolution vessel wall magnetic resonance imaging (HR-VWMRI) and combined it with clinical indicators. In total, 127 patients were finally enrolled and randomly divided into training and test cohorts. HR-VWMRI three-dimensional T1-weighted imaging (T1WI) and contrast-enhanced T1WI (T1CE) were collected. A traditional model was built by recording and calculating radiographic features of the carotid plaques and patients' clinical indicators. After extracting radiomics features from T1WI and T1CE images, the least absolute shrinkage and selection operator (LASSO) algorithm was used to select the optimal features and construct the radiomics_T1WI model and the radiomics_T1CE model. The traditional and radiomics features were used to build combined models. The performance of all the models predicting ischemic stroke was evaluated in the training and test cohorts, respectively. Body mass index (BMI) and intraplaque hemorrhage (IPH) were independently related to ischemic stroke and were used to build the traditional model, which achieved an area under the curve (AUC) of 0.79 versus 0.78 in the training and test cohorts, respectively. The AUC value of the radiomics_T1WI model is the lowest in the training and test cohorts, but the prediction performance is significantly improved when the model combines IPH and BMI. The AUC value of the combined_T1WI model was 0.78 and 0.81 in the training and test cohorts, respectively. In addition, in the training and test cohorts, the radiomics_T1CE model based on HR-VWMRI combined clinical characteristics, which is the combined_T1CE model, had the highest AUC value of 0.84 and 0.82, respectively. Compared with other models, the radiomics_T1CE model based on HR-VWMRI combined clinical characteristics, which is a combined_T1CE model, can accurately predict the risk of ischemic stroke.

Lipid-lowering Therapy and Coronary Plaque Regression.

Lipid-lowering therapy plays a central role in reducing cardiovascular events. Over the past few decades, clinical trials utilizing several imaging techniques have consistently shown that lipid-lowering therapy can reduce the coronary plaque burden and improve plaque composition. Although intravascular ultrasound has been the most extensively used modality to assess plaque burden, other invasive modalities, such as optical coherence tomography and near-infrared spectroscopy, provide relevant data on plaque vulnerability, and computed tomography angiography detects both plaque volume and characteristics non-invasively. A large body of evidence supports the notion that reducing low-density lipoprotein cholesterol using statins combined with ezetimibe and proprotein convertase subtillisin/kexin type 9 inhibitors consistently shows improvements in plaque burden and favorable morphological changes. This review summarizes previously obtained data on the impact of lipid-lowering treatment strategies on atherosclerotic plaque regression, as assessed using several imaging modalities.

Noninvasive carotid ultrasound for predicting vulnerable plaques of the coronary artery based on optical coherence tomography images.

The risk factors for coronary and carotid plaque development are consistent. Coronary plaque rupture is a major cause of adverse cardiovascular events. Ultrasound can evaluate vulnerable carotid plaques and provide information for predicting vulnerable coronary plaques identified by optical coherence tomography (OCT). This study aimed to investigate the predictive role of non-invasive carotid ultrasound in OCT diagnosis of atherosclerotic vulnerable plaque. A total of 70 participants, including 35 patients with and 35 without vulnerable coronary plaque, were enrolled in this case-control study at Beijing Anzhen Hospital from 2016 to 2021. The data of 70 patients with suspected coronary heart disease who had undergone OCT examination during percutaneous coronary intervention (PCI) surgery and completed carotid ultrasound examination within 3 days before PCI were analyzed retrospectively. According to the OCT diagnostic criteria for vulnerable plaques, the patients were divided into the vulnerable-plaque group and the stable-plaque group. Univariate and binary logistic regression analyses assessed risk factors for vulnerable coronary plaque. Receiver operating characteristic (ROC) curve analysis was used to determine the predictive power of carotid plaque features. The univariate analysis demonstrated that the differences in high-sensitivity C-reactive protein levels and carotid plaque characteristics (irregular fibrous cap, heterogeneous plaque, hypoechoic plaque, plaque calcification, and a plaque thickness of greater than 3 mm) between the two groups were statistically significant. The logistic multivariate regression analysis revealed that an irregular fibrous cap of a carotid plaque [odds ratio (OR) =4.819; 95% confidence interval (CI): 1.106-22.867; P=0.048] and a hypoechoic plaque (OR =9.632; 95% CI: 2.138-43.384; P<0.05) were independent risk factors for predicting vulnerable plaques of the coronary artery. Noninvasive carotid ultrasound is feasible and clinically valuable for predicting vulnerable and asymptomatic coronary plaques defined by OCT. With this method, adverse events can be diagnosed and treated in advance.

Lipid Content Distribution and its Clinical Implication in Patients with Acute Myocardial Infarction-Plaque Erosion: Results from the Prospective OCTAMI Study.

Plaque erosion (PE) is one of the main plaque phenotypes of acute coronary syndrome (ACS). However, the underlying plaque component and distribution have not been systematically analysed. This study aims to investigate the distribution of lipid and calcium content in culprit lesions assessed by optical coherence tomography (OCT) in patients with PE and explore its relationship with prognosis in a cohort of ST segment elevation myocardial infarction (STEMI) patients. A prospective cohort of 576 patients with STEMI was enrolled in our study. After exclusion, 152 PE patients with clear underlying plaque components were ultimately analysed. The culprit lesion was divided into the border zone, external erosion zone and erosion site in the longitudinal view. Each pullback of the culprit lesions was assessed by 3 independent investigators frame-by-frame, and the quantity and distribution of lipid and calcium components were recorded. Of the 152 PE patients, lipid and calcium contents were more likely to exist in the external erosion zone than in the other regions. In particular, a high level of lipid content proximal to the erosion site was significantly associated with plaque vulnerability and a higher incidence of MACEs. This study revealed that high level of lipid content in the proximal external erosion zone was related to high-risk plaque characteristics and poor prognosis, which provided a novel method for risk stratification and precise management in patients with plaque erosion.

NIRS-IVUS Assessment of OCT-Derived Healed Coronary Plaques.

Healed plaque (HP) is associated with rapid plaque growth and luminal narrowing. Thin-cap fibroatheroma (TCFA) is recognized as a precursor lesion to plaque rupture. The aim of the present study was to compare the lipid size among optical coherence tomography (OCT)-derived HP, TCFA, and thick-cap fibroatheroma (ThCFA) using near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS). The present study included 173 patients with acute myocardial infarction (AMI) who underwent percutaneous coronary intervention. Non-culprit lesions with angiographically intermediate stenosis were assessed by both OCT and NIRS-IVUS. The frequency of TCFA, HP, and ThCFA was 35 (20%), 53 (30%), and 85 (49%), respectively. Minimum lumen area was not significantly different between TCFA and HP, but was smaller in TCFA and HP than in ThCFA (4.6 [interquartile range {IQR}: 3.5-6.4] mm2 vs. 4.3 [3.4-5.3] mm2 vs. 6.5 [4.8-8.6] mm2, P＜0.001). Plaque burden was not significantly different between TCFA and HP, but was larger in TCFA and HP than in ThCFA (72 [IQR: 66-80] % vs. 75 [67-80] % vs. 62 [54-69] %, P＜0.001). Maximum lipid core burden index in 4mm (maxLCBI4mm) was largest in TCFA, followed by HP and ThCFA (493 [IQR: 443-606] vs. 446 [347-520] vs. 231 [161-302], P＜0.001). The frequency of lipid rich plaque with maxLCBI4mm ＞400 was highest in TCFA, followed by HP and ThCFA (89% vs. 60% vs. 7%, P＜0.001). Based on NIRS-IVUS findings, non-culprit coronary HP in AMI was associated with vulnerable plaque characteristics, but not as much as TCFA.