From Detecting the Vulnerable Plaque to Managing the Vulnerable Patient: JACC State-of-the-Art Review

Combined conventional factors and the radiomics signature of coronary plaque texture could improve cardiac risk prediction

OBJECTIVES

This study aims to investigate how radiomics analysis can help understand the association between plaque texture, epicardial adipose tissue (EAT), and cardiovascular risk. Working with a Photon-counting CT, which exhibits enhanced feature stability, offers the potential to advance radiomics analysis and enable its integration into clinical routines.

METHODS

Coronary plaques were manually segmented in this retrospective, single-centre study and radiomic features were extracted using pyradiomics. The study population was divided into groups according to the presence of high-risk plaques (HRP), plaques with at least 50% stenosis, plaques with at least 70% stenosis, or triple-vessel disease. A combined group with patients exhibiting at least one of these risk factors was formed. Random forest feature selection identified differentiating features for the groups. EAT thickness and density were measured and compared with feature selection results.

RESULTS

A total number of 306 plaques from 61 patients (mean age 61 years +/- 8.85 [standard deviation], 13 female) were analysed. Plaques of patients with HRP features or relevant stenosis demonstrated a higher presence of texture heterogeneity through various radiomics features compared to patients with only an intermediate stenosis degree. While EAT thickness did not significantly differ, affected patients showed significantly higher mean densities in the 50%, HRP, and combined groups, and insignificantly higher densities in the 70% and triple-vessel groups.

CONCLUSION

The combination of a higher EAT density and a more heterogeneous plaque texture might offer an additional tool in identifying patients with an elevated risk of cardiovascular events.

CLINICAL RELEVANCE STATEMENT

Cardiovascular disease is the leading cause of mortality globally. Plaque composition and changes in the EAT are connected to cardiac risk. A better understanding of the interrelation of these risk indicators can lead to improved cardiac risk prediction.

KEY POINTS

Cardiac plaque composition and changes in the EAT are connected to cardiac risk. Higher EAT density and more heterogeneous plaque texture are related to traditional risk indicators. Radiomics texture analysis conducted on PCCT scans can help identify patients with elevated cardiac risk.

The LDL cumulative exposure hypothesis: evidence and practical applications

The trapping of LDL and other apolipoprotein B-containing lipoproteins within the artery wall causes atherosclerosis. As more LDL becomes trapped within the artery wall over time, the atherosclerotic plaque burden gradually increases, raising the risk of an acute cardiovascular event. Therefore, the biological effect of LDL on the risk of atherosclerotic cardiovascular disease (ASCVD) depends on both the magnitude and duration of exposure. Maintaining low levels of LDL-cholesterol (LDL-C) over time decreases the number of LDL particles trapped within the artery wall, slows the progression of atherosclerosis and, by delaying the age at which mature atherosclerotic plaques develop, substantially reduces the lifetime risk of ASCVD events. Summing LDL-C measurements over time to calculate cumulative exposure to LDL generates a unique biomarker that captures both the magnitude and duration of exposure, which facilitates the estimation of the absolute risk of having an acute cardiovascular event at any point in time. Titrating LDL-C lowering to keep cumulative exposure to LDL below the threshold at which acute cardiovascular events occur can effectively prevent ASCVD. In this Review, we provide the first comprehensive overview of how the LDL cumulative exposure hypothesis can guide the prevention of ASCVD. We also discuss the benefits of maintaining lower LDL-C levels over time and how this knowledge can be used to inform clinical practice guidelines as well as to design novel primary prevention trials and ASCVD prevention programmes.

The burden of sudden cardiac arrest in the setting of acute coronary syndrome

BACKGROUND

The incidence of sudden cardiac arrest (SCA) during acute coronary syndrome is somewhat unclear, since often subjects dying before the first healthcare contact are not included in the estimates. We aimed to investigate the complete incidence of SCA during ACS.

METHODS

The study population consists of two cohorts. The first cohort includes 472 ACS patients from Northern Ostrobothnia, Finland from year 2016 and the second cohort 162 autopsy-verified SCD subjects (extrapolated) from the same region and year, whose death was attributable to coronary artery disease (CAD) and ACS. An extrapolation of SCA incidence during ACS was done by utilizing autopsy data and data from prior autopsy study on this sample.

RESULTS

The overall incidence of SCA in the setting of ACS was 17.5%. The incidence of SCA was 20.6% in all ACS subjects without prior CAD diagnosis, and 25.4% in STEMI subjects without prior CAD diagnosis. In subjects with previously diagnosed CAD, the incidence of SCA was 10.9% in all ACS subjects and 16.1% in STEMI subjects. There was a statistically significant difference in the incidence of SCA between subjects with and without prior CAD diagnosis (p = 0.0052).

CONCLUSION

The inclusion of ACS-SCA subjects dying before the first emergency medical service (EMS) contact results in a higher and likely more accurate estimation of SCA during ACS. The incidence of SCA was higher among subjects without prior CAD diagnosis. The high mortality rate highlights the importance of early ACS detection to reduce the burden of CAD-related premature deaths.

Clinical impact of complex percutaneous coronary intervention in the pre-TAVR workup

INTRODUCTION AND OBJECTIVES

In patients undergoing percutaneous coronary intervention (PCI) in the workup pre-transcatheter aortic valve replacement (TAVR), the clinical impact of coronary revascularization complexity remains unknown. This study sought to examine the impact of PCI complexity on clinical outcomes after TAVR in patients undergoing PCI in the preprocedural workup.

METHODS

This was a multicenter study including consecutive patients scheduled for TAVR with concomitant significant coronary artery disease. Complex PCI was defined as having at least 1 of the following features: 3 vessels treated, ≥ 3 stents implanted, ≥ 3 lesions treated, bifurcation with 2 stents implanted, total stent length >60mm, or chronic total occlusion. The rates of major adverse cardiac events (MACE), including cardiovascular mortality, myocardial infarction, and coronary revascularization were evaluated.

RESULTS

A total of 1550 patients were included, of which 454 (29.3%) underwent complex PCI in the pre-TAVR workup. After a median follow-up period of 2 [1-3] years after TAVR, the incidence of MACE was 9.6 events per 100 patients-years. Complex PCI significantly increased the risk of cardiac death (HR, 1.44; 95%CI, 1.01-2.07), nonperiprocedural myocardial infarction (HR, 1.52; 95%CI, 1.04-2.21), and coronary revascularization (HR, 2.46; 95%CI, 1.44-4.20). In addition, PCI complexity was identified as an independent predictor of MACE after TAVR (HR, 1.31; 95%CI, 1.01-1.71; P=.042).

CONCLUSIONS

In TAVR candidates with significant coronary artery disease requiring percutaneous treatment, complex revascularization was associated with a higher risk of MACE. The degree of procedural complexity should be considered a strong determinant of prognosis in the PCI-TAVR population.

Drug-Coated Balloon in Acute Coronary Syndromes: Ready for the Prime Time?

PURPOSE OF REVIEW

Acute coronary syndromes (ACS) are a major global health concern. Percutaneous coronary intervention (PCI) with new-generation drug-eluting stents (DES) has been endorsed as safe and effective in the management of culprit and non-culprit lesions of ACS. However, permanent metallic implants may have drawbacks, including the need for prolonged dual antiplatelet therapy (DAPT) and the risk of long-term stent-related complications. An alternative approach using drug-coated balloons (DCBs) is gaining growing interest, having the potential of delivering therapy directly to vulnerable plaques, avoiding the need for permanent metallic implants, and potentially allowing for better long-term medical treatment. Despite limited evidence, DCB is being explored in several patients' subgroups. This review aims to discuss the existing evidence regarding DCB in ACS management.

RECENT FINDINGS

DCB appears to be a promising strategy in the management of ACS, showing comparable angiographic and clinical results as compared to new-generation DES in relatively small clinical trials or large prospective registries. The advantage of avoiding permanent implants is particularly appealing in this setting, where DCB has the potential of delivering anti-atherogenic local therapy directly to vulnerable plaques still amenable to atherogenic regression. This review seeks to underline the theoretical background of DCB use and reports the available evidence in its support in the specific setting of ACS. In the context of ACS, the use of DCB is highly attractive, offering a dedicated anti-atherogenic local therapy, capable of addressing a broad range of vulnerable plaques and patients.

Pancoronary plaque characteristics in STEMI patients with rapid plaque progression: An optical coherence tomography study

BACKGROUND

Non-culprit plaque progression is associated with recurrent cardiac ischemic events and worse clinical outcomes. Given that atherosclerosis is a systemic disease, the pancoronary characteristics of patients with rapid plaque progression are unknown. This study aims to identify pancoronary plaque features in patients with ST-segment elevation myocardial infarction (STEMI) with and without rapid plaque progression, focused on the patient level.

METHODS AND RESULTS

From January 2017 to July 2019, 291 patients underwent 3-vessel optical coherence tomography imaging at the time of the primary procedure and a follow-up angiography interval of 12 months. The final analysis included 237 patients. Overall, 308 non-culprit lesions were found in 78 STEMI patients with rapid plaque progression, and 465 non-culprit plaques were found in 159 STEMI patients without rapid plaque progression. These patients had a higher pancoronary vulnerability (CLIMA-defined high-risk plaque: 47.4% vs. 33.3%; non-culprit plaque rupture: 25.6% vs. 14.5%) and a significantly higher prevalence of other vulnerable plaque characteristics (i.e., lipid-rich plaque, cholesterol crystal, microchannels, calcification, spotty calcification, and thrombus) at baseline versus those without rapid plaque progression. Lesions with rapid progression were highly distributed at the LAD, tending to be near the bifurcation. In multivariate analysis, age ≥ 65 years was an independent predictor of subsequent rapid lesion progression at the patient level, whereas microchannel, spotty calcification, and cholesterol crystal were independent predictors for STEMI patients ≥65 years old.

CONCLUSIONS

STEMI patients with subsequent rapid plaque progression had higher pancoronary vulnerability and commonly presented vulnerable plaque morphology. Aging was the only predictor of subsequent rapid plaque progression.

An Integrated Arterial Remodeling Hydrogel for Preventing Restenosis After Angioplasty

The high incidence of restenosis after angioplasty has been the leading reason for the recurrence of coronary heart disease, substantially increasing the mortality risk for patients. However, current anti-stenosis drug-eluting stents face challenges due to their limited functions and long-term safety concerns, significantly compromising their therapeutic effect. Herein, a stent-free anti-stenosis drug coating (denoted as Cur-NO-Gel) based on a peptide hydrogel is proposed. This hydrogel is formed by assembling a nitric oxide (NO) donor-peptide conjugate as a hydrogelator and encapsulating curcumin (Cur) during the assembly process. Cur-NO-Gel has the capability to release NO upon β-galactosidase stimulation and gradually release Cur through hydrogel hydrolysis. The in vitro experiments confirmed that Cur-NO-Gel protects vascular endothelial cells against oxidative stress injury, inhibits cellular activation of vascular smooth muscle cells, and suppresses adventitial fibroblasts. Moreover, periadventitial administration of Cur-NO-Gel in the angioplasty model demonstrate its ability to inhibit vascular stenosis by promoting reendothelialization, suppressing neointima hyperplasia, and preventing constrictive remodeling. Therefore, the study provides proof of concept for designing a new generation of clinical drugs in angioplasty.

Elucidating the mechanisms of formononetin in modulating atherosclerotic plaque formation in ApoE-/- mice

BACKGROUND

Atherosclerosis(AS) poses a pressing challenge in contemporary medicine. Formononetin (FMN) plays a crucial role in its prevention and treatment. However, the detailed impact of FMN on the stability of atherosclerotic plaques and its underlying mechanisms remain to be elucidated.

METHODS

An intervention consisting of FMN was given along with a high-fat food regimen in the ApoE-/- mouse model. The investigation included the evaluation of the degree of atherosclerotic lesion, the main components of the plaque, lipid profiles, particular markers indicating M1/M2 macrophage phenotypes, the quantities of factors related to inflammation, the infiltration of macrophages, and the identification of markers linked to the α7nAChR/JAK2/STAT3 axis effect molecules.

RESULTS

The evaluation of aortic morphology in ApoE-/-mice revealed that FMN significantly improved the plaque area, fibrous cap protrusion, lipid deposition, and structural alterations on the aortic surface, among other markers of atherosclerosis,and there is concentration dependence. Furthermore, the lipid content of mouse serum was assessed, and the results showed that the low-, medium-, and high-dosage FMN groups had significantly lower levels of LDL-C, ox-LDL, TC, and TG. The results of immunohistochemical staining indicated that the low-, medium-, and high-dose FMN therapy groups had enhanced CD206 expression and decreased expression of CD68 and iNOS. According to RT-qPCR data, FMN intervention has the potential to suppress the expression of iNOS, COX-2, miR-155-5p, IL-6, and IL-1β mRNA, while promoting the expression of IL-10, SHIP1, and Arg-1 mRNA levels. However, the degree of inhibition varied among dosage groups. Western blot investigation of JAK/STAT signaling pathway proteins and cholinergic α7nAChR protein showed that p-JAK2 and p-STAT3 protein expression was suppressed at all dosages, whereas α7nAChR protein expression was enhanced.

CONCLUSIONS

According to the aforementioned findings, FMN can reduce inflammation and atherosclerosis by influencing macrophage polarization, blocking the JAK/STAT signaling pathway, and increasing α7nAChR expression.

MiR-130a-3p inhibits endothelial inflammation by regulating the expression of MAPK8 in endothelial cells

MicroRNA-130a-3p (miR-130a-3p) has been reported as closely related to atherosclerosis (AS). This study is to survey the effects of miR-130a-3p in endothelial cells (ECs) treated with oxidized low-density lipoprotein (ox-LDL) and explore underlying mechanisms. The proliferation and apoptosis of ox-LDL-treated HUVEC cells were determined by CCK-8, EdU, and flow cytometry assays. ELISA and Western blot analysis measured the expressions of cytokines and protein levels. Bioinformatics and dual-luciferase reporter assay were performed to predict and confirm that Mitogen-activated protein kinase 8 (MAPK8) was a direct target of miR-130a-3p, and MAPK8 was negatively associated with miR-130a-3p. As expected, miR-130a-3p was down-regulated in ox-LDL-treated HUVEC cells, and up-regulation of miR-130a-3p promoted proliferation and inhibited apoptosis of ox-LDL-treated HUVEC cells. Furthermore, miR-130a-3p mimics suppressed the expressions of TNF-α and IL-6 and decreased the protein levels of VCAM-1, ICAM-1 and E-selectin. MAPK8 was highly expressed in ox-LDL-treated HUVEC cells, and silence of MAPK8 promoted proliferation inhibited apoptosis, suppressed inflammatory responses, and decreased the levels of VCAM-1, ICAM-1, and E-selectin, over-expression of MAPK8 partially restored the functional effects of miR-130a-3p on proliferation, inflammatory responses, and the expressions of VCAM-1, ICAM-1 and E-selectin. This study indicates that miR-130a-3p may emerge as an effective target for treating AS.

Coronary microevaginations characterize culprit plaques and their inflammatory microenvironment in a subtype of acute coronary syndrome with intact fibrous cap: results from the prospective translational OPTICO-ACS study

AIMS

Coronary microevaginations (CMEs) represent an outward bulge of coronary plaques and have been introduced as a sign of adverse vascular remodelling following coronary device implantation. However, their role in atherosclerosis and plaque destabilization in the absence of coronary intervention is unknown. This study aimed to investigate CME as a novel feature of plaque vulnerability and to characterize its associated inflammatory cell-vessel-wall interactions.

METHODS AND RESULTS

A total of 557 patients from the translational OPTICO-ACS study programme underwent optical coherence tomography imaging of the culprit vessel and simultaneous immunophenotyping of the culprit lesion (CL). Two hundred and fifty-eight CLs had a ruptured fibrous cap (RFC) and one hundred had intact fibrous cap (IFC) acute coronary syndrome (ACS) as an underlying pathophysiology. CMEs were significantly more frequent in CL when compared with non-CL (25 vs. 4%, P < 0.001) and were more frequently observed in lesions with IFC-ACS when compared with RFC-ACS (55.0 vs. 12.7%, P < 0.001). CMEs were particularly prevalent in IFC-ACS-causing CLs independent of a coronary bifurcation (IFC-ICB) when compared with IFC-ACS with an association to a coronary bifurcation (IFC-ACB, 65.4 vs. 43.7%, P = 0.030). CME emerged as the strongest independent predictor of IFC-ICB (relative risk 3.36, 95% confidence interval 1.67-6.76, P = 0.001) by multivariable regression analysis. IFC-ICB demonstrated an enrichment of monocytes in both culprit blood analysis (culprit ratio: 1.1 ± 0.2 vs. 0.9 ± 0.2, P = 0.048) and aspirated culprit thrombi (326 ± 162 vs. 96 ± 87 cells/mm2, P = 0.017), while IFC-ACB confirmed the accumulation of CD4+ T cells, as recently described.

CONCLUSION

This study provides novel evidence for a pathophysiological involvement of CME in the development of IFC-ACS and provides first evidence for a distinct pathophysiological pathway for IFC-ICB, driven by CME-derived flow disturbances and inflammatory activation involving the innate immune system.

TRIAL REGISTRATION

Registration of the study at clinicalTrials.gov (NCT03129503).

Multimodal Prognostic Model for Predicting Chronic Coronary Artery Disease in Patients Without Obstructive Sleep Apnea Syndrome

BACKGROUND

Obstructive sleep apnea syndrome (OSAS), with metabolic disorders as a central feature, is closely correlated with coronary artery disease (CAD). Our goal was to develop a prediction nomogram that integrated multimodal data that could accurately predict the prognosis of patients with chronic coronary disease (CCD).

METHODS

We evaluated 393 patients with CCD with a low-to-intermediate pretest probability of OSAS based on polysomnography. A nomogram was constructed by means of least absolute shrinkage and selection operator (LASSO) and multiple Cox regression analyses to identify independent risk factors for major adverse cardiovascular events (MACEs).

RESULTS

Two hundred seventy-seven patients were randomly assigned to the training set, and 116 to the verification set. The constructed nomogram consisted of seven clinical variables: age, previous CAD, current alcohol consumption, neck circumference, apnea-hypopnea index (AHI), and triglyceride-glucose index (TyG). The nomogram showed good discriminatory power, as evidenced by Harrell's C-index values of 0.79 (95% confidence interval [CI] 0.731-0.849) in the training set and 0.78 (95% CI 0.678-0.882) in the verification set. Moreover, a high correlation was observed between the predicted and actual incidence of MACEs in both the training and verification sets. Decision curve analysis demonstrated excellent clinical utility of the nomogram based on net benefit and threshold probabilities.

CONCLUSIONS

We developed an integrated visualized prognostic nomogram that utilizes multi-modal data, including clinical characteristics, AHI, and TyG index, to predict MACEs in patients with CCD. This approach demonstrated excellent performance, highlighting the potential of combining different data sources to enhance prediction accuracy.

Use of coronary artery calcium score and coronary CT angiography to guide cardiovascular prevention and treatment

Currently, cardiovascular risk stratification to guide preventive therapy relies on clinical scores based on cardiovascular risk factors. However, the discriminative power of these scores is relatively modest. The use of coronary artery calcium score (CACS) and coronary CT angiography (CCTA) has surfaced as methods for enhancing the estimation of risk and potentially providing insights for personalized treatment in individual patients. CACS improves overall cardiovascular risk prediction and may be used to improve the yield of statin therapy in primary prevention, and possibly identify patients with a favorable risk/benefit relationship for antiplatelet therapies. CCTA holds promise to guide anti-atherosclerotic therapies and to monitor individual response to these treatments by assessing individual plaque features, quantifying total plaque volume and composition, and assessing peri-coronary adipose tissue. In this review, we aim to summarize current evidence regarding the use of CACS and CCTA for guiding lipid-lowering and antiplatelet therapy and discuss the possibility of using plaque burden and plaque phenotyping to monitor response to anti-atherosclerotic therapies.

Long-term intracoronary imaging and physiological measurements of bioresorbable scaffolds and untreated atherosclerotic plaques

BACKGROUND

Bioresorbable scaffolds (BRS) provide the prospect of restoring the anatomic and physiologic characteristics of the vascular wall.

OBJECTIVE

This study sought to examine the long-term outcomes of BRS-based coronary intervention in a young population with diffuse and severe coronary atherosclerotic disease (CAD) and to compare the long-term evolution of treated segments versus the natural progression of untreated non-flow limiting stenoses.

METHODS

Observational, single-center cohort study that prospectively included patients that underwent percutaneous coronary intervention with implantation of ABSORB BRS (Abbott Vascular). The clinical endpoint was the incidence of device-oriented composite endpoint (DoCE) up to 5 years follow-up. A subgroup of patients with baseline intracoronary imaging assessment of long lesions and/or multivessel disease underwent elective angiographic (70 patients, 129 lesions) and intracoronary imaging (55 patients, 102 lesions) follow-up. Paired intravascular ultrasound (IVUS) and quantitative flow reserve (QFR) were analyzed.

RESULTS

Between 2012 and 2017, 159 patients (mean age 54.0 ± 11.1) with native CAD were treated with BRS on 247 lesions. Patients were mainly at their first cardiac event, mostly acute coronary syndromes (86.5%). At the median follow-up time of 56 months [41-65], DoCE occurred in 15/159 (9.4%) patients, while non-target vessel-oriented composite endpoint occurred in 16 patients (10.4%). A significant atherosclerotic progression was detected on residual non-flow limiting plaques as per IVUS and QFR assessment, while no significant change was detected in the treated segment.

CONCLUSIONS

Mild-to-moderate asymptomatic CAD progressed significantly at 5-year despite OMT. BRS-treated segments had a less aggressive progression at 5-year despite more severe and symptomatic CAD at baseline.

Roadmap on the use of artificial intelligence for imaging of vulnerable atherosclerotic plaque in coronary arteries

Artificial intelligence (AI) is likely to revolutionize the way medical images are analysed and has the potential to improve the identification and analysis of vulnerable or high-risk atherosclerotic plaques in coronary arteries, leading to advances in the treatment of coronary artery disease. However, coronary plaque analysis is challenging owing to cardiac and respiratory motion, as well as the small size of cardiovascular structures. Moreover, the analysis of coronary imaging data is time-consuming, can be performed only by clinicians with dedicated cardiovascular imaging training, and is subject to considerable interreader and intrareader variability. AI has the potential to improve the assessment of images of vulnerable plaque in coronary arteries, but requires robust development, testing and validation. Combining human expertise with AI might facilitate the reliable and valid interpretation of images obtained using CT, MRI, PET, intravascular ultrasonography and optical coherence tomography. In this Roadmap, we review existing evidence on the application of AI to the imaging of vulnerable plaque in coronary arteries and provide consensus recommendations developed by an interdisciplinary group of experts on AI and non-invasive and invasive coronary imaging. We also outline future requirements of AI technology to address bias, uncertainty, explainability and generalizability, which are all essential for the acceptance of AI and its clinical utility in handling the anticipated growing volume of coronary imaging procedures.

Rationale and design of the CONFIRM2 (Quantitative COroNary CT Angiography Evaluation For Evaluation of Clinical Outcomes: An InteRnational, Multicenter Registry) study

BACKGROUND

In the last 15 years, large registries and several randomized clinical trials have demonstrated the diagnostic and prognostic value of coronary computed tomography angiography (CCTA). Advances in CT scanner technology and developments of analytic tools now enable accurate quantification of coronary artery disease (CAD), including total coronary plaque volume and low attenuation plaque volume. The primary aim of CONFIRM2, (Quantitative COroNary CT Angiography Evaluation For Evaluation of Clinical Outcomes: An InteRnational, Multicenter Registry) is to perform comprehensive quantification of CCTA findings, including coronary, non-coronary cardiac, non-cardiac vascular, non-cardiac findings, and relate them to clinical variables and cardiovascular clinical outcomes.

DESIGN

CONFIRM2 is a multicenter, international observational cohort study designed to evaluate multidimensional associations between quantitative phenotype of cardiovascular disease and future adverse clinical outcomes in subjects undergoing clinically indicated CCTA. The targeted population is heterogenous and includes patients undergoing CCTA for atherosclerotic evaluation, valvular heart disease, congenital heart disease or pre-procedural evaluation. Automated software will be utilized for quantification of coronary plaque, stenosis, vascular morphology and cardiac structures for rapid and reproducible tissue characterization. Up to 30,000 patients will be included from up to 50 international multi-continental clinical CCTA sites and followed for 3-4 years.

SUMMARY

CONFIRM2 is one of the largest CCTA studies to establish the clinical value of a multiparametric approach to quantify the phenotype of cardiovascular disease by CCTA using automated imaging solutions.

Noninvasive Coronary Atherosclerotic Plaque Imaging

Coronary artery disease is the leading cause of morbidity and mortality worldwide. Despite remarkable advances in the management of coronary artery disease, the prediction of adverse coronary events remains challenging. Over the preceding decades, considerable effort has been made to improve risk stratification using noninvasive imaging. Recently, these efforts have increasingly focused on the direct imaging of coronary atherosclerotic plaque. Modern imaging now allows imaging of coronary plaque burden, plaque type, atherosclerotic plaque activity, and plaque thrombosis, which have major potential to refine patient risk stratification, aid decision making, and advance future clinical practice.

The microenvironment of the atheroma expresses phenotypes of plaque instability

Data from histopathology studies of human atherosclerotic tissue specimens and from vascular imaging studies support the concept that the local arterial microenvironment of a stable atheroma promotes destabilizing conditions that result in the transition to an unstable atheroma. Destabilization is characterized by several different plaque phenotypes that cause major clinical events such as acute coronary syndrome and cerebrovascular strokes. There are several rupture-associated phenotypes causing thrombotic vascular occlusion including simple fibrous cap rupture of an atheroma, fibrous cap rupture at site of previous rupture-and-repair of an atheroma, and nodular calcification with rupture. Endothelial erosion without rupture has more recently been shown to be a common phenotype to promote thrombosis as well. Microenvironment features that are linked to these phenotypes of plaque instability are neovascularization arising from the vasa vasorum network leading to necrotic core expansion, intraplaque hemorrhage, and cap rupture; activation of adventitial and perivascular adipose tissue cells leading to secretion of cytokines, growth factors, adipokines in the outer artery wall that destabilize plaque structure; and vascular smooth muscle cell phenotypic switching through transdifferentiation and stem/progenitor cell activation resulting in the promotion of inflammation, calcification, and secretion of extracellular matrix, altering fibrous cap structure, and necrotic core growth. As the technology evolves, studies using noninvasive vascular imaging will be able to investigate the transition of stable to unstable atheromas in real time. A limitation in the field, however, is that reliable and predictable experimental models of spontaneous plaque rupture and/or erosion are not currently available to study the cell and molecular mechanisms that regulate the conversion of the stable atheroma to an unstable plaque.

High dietary inflammatory index is associated with decreased plaque stability in patients with coronary heart disease

Coronary plaque stability is a key pathological mechanism of coronary heart disease (CHD). Inflammation is recognized as a key factor of coronary plaque stability. The dietary inflammatory index (DII) is calculated from 21 dietary nutrients to predict the inflammation potential of an individual's diet. We hypothesized that high DII may be associated with decreased coronary plaque stability in CHD patients; therefore, this study aimed to evaluate the association between DII and plaque stability in patients with CHD. This cross-sectional study included 314 patients with CHD. DII was calculated based on food frequency questionnaires. Plaque stability was measured with optical coherence tomography. The DII ranged from -1.41 to 3.04. After adjusting for confounding factors, higher DII scores were associated with unstable plaque characteristics including thin-capped fibroatheroma (odds ratio [OR], 3.60; 95% confidence interval [CI], 1.78-7.29), macrophage infiltration (OR, 2.16; 95% CI, 1.01-4.61), and plaque rupture (OR, 3.55; 95% CI, 1.73-7.29). Mediation analyses revealed that DII was important mediator of the relationship between plaque stability and food intake including soybeans and nuts, fish and shrimp, eggs (P < .05). The present study confirmed that higher DII is significantly associated with decreased plaque stability in CHD patients, suggesting an important protective role of anti-inflammatory diets in the pathogenesis of CHD.

Coronary artery disease grading by cardiac CT for predicting outcome in patients with stable angina

BACKGROUND

The coronary atheroma burden drives major adverse cardiovascular events (MACE) in patients with suspected coronary heart disease (CHD). However, a consensus on how to grade disease burden for effective risk stratification is lacking. The purpose of this study was to compare the effectiveness of common CHD grading tools to risk stratify symptomatic patients.

METHODS

We analyzed the 5-year outcome of 381 prospectively enrolled patients in the CORE320 international, multicenter study using baseline clinical and cardiac computer-tomography (CT) imaging characteristics, including coronary artery calcium score (CACS), percent atheroma volume, "high-risk" plaque, disease severity grading using the CAD-RADS, and two simplified CAD staging systems. We applied Cox proportional hazard models and area under the curve (AUC) analysis to predict MACE or hard MACE, defined as death, myocardial infarction, or stroke. Analyses were stratified by a history of CHD. Additional forward selection analysis was performed to evaluate incremental value of metrics.

RESULTS

Clinical characteristics were the strongest predictors of MACE in the overall cohort. In patients without history of CHD, CACS remained the only independent predictor of MACE yielding an AUC of 73 (CI 67-79) vs. 64 (CI 57-70) for clinical characteristics. Noncalcified plaque volume did not add prognostic value. Simple CHD grading schemes yielded similar risk stratification as the CAD-RADS classification. Forward selection analysis confirmed prominent role of CACS and revealed usefulness of functional testing in subgroup with known CHD.

CONCLUSION

In patients referred for invasive angiography, a history of CHD was the strongest predictor of MACE. In patients without history of CHD, a coronary calcium score yielded at least equal risk stratification vs. more complex CHD grading.

Detection and Imaging of Active Substances in Early Atherosclerotic Lesions Using Fluorescent Probes

Atherosclerosis (AS) is a vascular disease caused by chronic inflammation and lipids that is the main cause of myocardial infarction, stroke and other cardiovascular diseases. Atherosclerosis is often difficult to detect in its early stages due to the absence of clinically significant vascular stenosis. This is not conducive to early intervention or treatment of the disease. Over the past decade, researchers have developed various imaging methods for the detection and imaging of atherosclerosis. At the same time, more and more biomarkers are being found that can be used as targets for detecting atherosclerosis. Therefore, the development of a variety of imaging methods and a variety of targeted imaging probes is an important project to achieve early assessment and treatment of atherosclerosis. This paper provides a comprehensive review of the optical probes used to detect and target atherosclerosis imaging in recent years, and describes the current challenges and future development directions.

Coronary Atherosclerotic Plaque Activity and Future Coronary Events

Importance

Recurrent coronary events in patients with recent myocardial infarction remain a major clinical problem. Noninvasive measures of coronary atherosclerotic disease activity have the potential to identify individuals at greatest risk.

Objective

To assess whether coronary atherosclerotic plaque activity as assessed by noninvasive imaging is associated with recurrent coronary events in patients with myocardial infarction.

Design, Setting, and Participants

This prospective, longitudinal, international multicenter cohort study recruited participants aged 50 years or older with multivessel coronary artery disease and recent (within 21 days) myocardial infarction between September 2015 and February 2020, with a minimum 2 years' follow-up.

Intervention

Coronary 18F-sodium fluoride positron emission tomography and coronary computed tomography angiography.

Main Outcomes and Measures

Total coronary atherosclerotic plaque activity was assessed by 18F-sodium fluoride uptake. The primary end point was cardiac death or nonfatal myocardial infarction but was expanded during study conduct to include unscheduled coronary revascularization due to lower than anticipated primary event rates.

Results

Among 2684 patients screened, 995 were eligible, 712 attended for imaging, and 704 completed an interpretable scan and comprised the study population. The mean (SD) age of participants was 63.8 (8.2) years, and most were male (601 [85%]). Total coronary atherosclerotic plaque activity was identified in 421 participants (60%). After a median follow-up of 4 years (IQR, 3-5 years), 141 participants (20%) experienced the primary end point: 9 had cardiac death, 49 had nonfatal myocardial infarction, and 83 had unscheduled coronary revascularizations. Increased coronary plaque activity was not associated with the primary end point (hazard ratio [HR], 1.25; 95% CI, 0.89-1.76; P = .20) or unscheduled revascularization (HR, 0.98; 95% CI, 0.64-1.49; P = .91) but was associated with the secondary end point of cardiac death or nonfatal myocardial infarction (47 of 421 patients with high plaque activity [11.2%] vs 19 of 283 with low plaque activity [6.7%]; HR, 1.82; 95% CI, 1.07-3.10; P = .03) and all-cause mortality (30 of 421 patients with high plaque activity [7.1%] vs 9 of 283 with low plaque activity [3.2%]; HR, 2.43; 95% CI, 1.15-5.12; P = .02). After adjustment for differences in baseline clinical characteristics, coronary angiography findings, and Global Registry of Acute Coronary Events score, high coronary plaque activity was associated with cardiac death or nonfatal myocardial infarction (HR, 1.76; 95% CI, 1.00-3.10; P = .05) but not with all-cause mortality (HR, 2.01; 95% CI, 0.90-4.49; P = .09).

Conclusions and Relevance

In this cohort study of patients with recent myocardial infarction, coronary atherosclerotic plaque activity was not associated with the primary composite end point. The findings suggest that risk of cardiovascular death or myocardial infarction in patients with elevated plaque activity warrants further research to explore its incremental prognostic implications.

Elevated FAI Index of Pericoronary Inflammation on Coronary CT Identifies Increased Risk of Coronary Plaque Vulnerability after COVID-19 Infection

Inflammation is a key factor in the development of atherosclerosis, a disease characterized by the buildup of plaque in the arteries. COVID-19 infection is known to cause systemic inflammation, but its impact on local plaque vulnerability is unclear. Our study aimed to investigate the impact of COVID-19 infection on coronary artery disease (CAD) in patients who underwent computed tomography angiography (CCTA) for chest pain in the early stages after infection, using an AI-powered solution called CaRi-Heart^®. The study included 158 patients (mean age was 61.63 ± 10.14 years) with angina and low to intermediate clinical likelihood of CAD, with 75 having a previous COVID-19 infection and 83 without infection. The results showed that patients who had a previous COVID-19 infection had higher levels of pericoronary inflammation than those who did not have a COVID-19 infection, suggesting that COVID-19 may increase the risk of coronary plaque destabilization. This study highlights the potential long-term impact of COVID-19 on cardiovascular health, and the importance of monitoring and managing cardiovascular risk factors in patients recovering from COVID-19 infection. The AI-powered CaRi-Heart^® technology may offer a non-invasive way to detect coronary artery inflammation and plaque instability in patients with COVID-19.

Predicting long-term prognosis after percutaneous coronary intervention in patients with new onset ST-elevation myocardial infarction: development and external validation of a nomogram model

BACKGROUND

The triglyceride glucose (TyG) index is a well-established biomarker for insulin resistance (IR) that shows correlation with poor outcomes in patients with coronary artery disease. We aimed to integrate the TyG index with clinical data in a prediction nomogram for the long-term prognosis of new onset ST-elevation myocardial infarction (STEMI) following primary percutaneous coronary intervention (PCI) .

METHODS

This retrospective study included new-onset STEMI patients admitted at two heart centers for emergency PCI from December 2015 to March 2018 in development and independent validation cohorts. Potential risk factors were screened applying least absolute shrinkage and selection operator (LASSO) regression. Multiple Cox regression was employed to identify independent risk factors for prediction nomogram construction. Nomogram performance was assessed based on receiver operating characteristic curve analysis, calibration curves, Harrell's C-index and decision curve analysis (DCA).

RESULTS

In total, 404 patients were assigned to the development cohort and 169 to the independent validation cohort. The constructed nomogram included four clinical variables: age, diabetes mellitus, current smoking, and TyG index. The Harrell's C-index values for the nomogram were 0.772 (95% confidence interval [CI]: 0.721-0.823) in the development cohort and 0.736 (95%CI: 0.656-0.816) in the independent validation cohort. Significant correlation was found between the predicted and actual outcomes in both cohorts, indicating that the nomogram is well calibrated. DCA confirmed the clinical value of the development prediction nomogram.

CONCLUSIONS

Our validated prediction nomogram based on the TyG index and electronic health records data was shown to provide accurate and reliable discrimination of new-onset STEMI patients at high- and low-risk for major adverse cardiac events at 2, 3 and 5 years following emergency PCI.

Role of plaque imaging for identification of vulnerable patients beyond the stage of myocardial ischemia

Chronic coronary syndrome (CCS) is a progressive disease, which often first manifests as acute coronary syndrome (ACS). Imaging modalities are clinically useful in making decisions about the management of patients with CCS. Accumulating evidence has demonstrated that myocardial ischemia is a surrogate marker for CCS management; however, its ability to predict cardiovascular death or nonfatal myocardial infarction is limited. Herein, we present a review that highlights the latest knowledge available on coronary syndromes and discuss the role and limitations of imaging modalities in the diagnosis and management of patients with coronary artery disease. This review covers the essential aspects of the role of imaging in assessing myocardial ischemia and coronary plaque burden and composition. Furthermore, recent clinical trials on lipid-lowering and anti-inflammatory therapies have been discussed. Additionally, it provides a comprehensive overview of intracoronary and noninvasive cardiovascular imaging modalities and an understanding of ACS and CCS, with a focus on histopathology and pathophysiology.

Tissue Engineering and Targeted Drug Delivery in Cardiovascular Disease: The Role of Polymer Nanocarrier for Statin Therapy

Atherosclerosis-related coronary artery disease (CAD) is the leading cause of mortality and morbidity worldwide. This requires effective primary and secondary prevention in reducing the complications related to CAD; the regression or stabilization of the pathology remains the mainstay of treatment. Statins have proved to be the most effective treatment in reducing adverse effects, but there are limitations related to the administration and achievement of effective doses as well as side effects due to the lack of target-related molecular specificity. The implemented technological steps are polymers and nanoparticles for the administration of statins, as it has been seen how the conjugation of drug delivery systems (DDSs) with statins increases bioavailability by circumventing the hepatic–renal filter and increases the related target specificity, enhancing their action and decreasing side effects. Reduction of endothelial dysfunction, reduced intimal hyperplasia, reduced ischemia–reperfusion injury, cardiac regeneration, positive remodeling in the extracellular matrix, reduced neointimal growth, and increased reendothelialization are all drug-related effects of statins enhanced by binding with DDSs. Recent preclinical studies demonstrate how the effect of statins stimulates the differentiation of endogenous cardiac stem cells. Poly-lactic-co-glycolic acid (PLGA) seems to be the most promising DDS as it succeeds more than the others in enhancing the effect of the bound drug. This review intends to summarize the current evidence on polymers and nanoparticles for statin delivery in the field of cardiovascular disease, trying to shed light on this topic and identify new avenues for future studies.

Evolving concepts of the vulnerable atherosclerotic plaque and the vulnerable patient: implications for patient care and future research

Understanding the natural history of coronary artery atherosclerosis is necessary to determine prognosis and prescribe effective therapies. Traditional management of coronary artery disease has focused on the treatment of flow-limiting anatomical obstructions that lead to ischaemia. In most scenarios, revascularization of these atherosclerotic plaques has not substantially improved freedom from death or myocardial infarction, questioning the utility of contemporary revascularization strategies to improve prognosis. Advances in non-invasive and invasive imaging techniques have helped to identify the characteristics of obstructive and non-obstructive plaques that are precursors for plaque progression and future acute coronary syndromes as well as cardiac death. These 'vulnerable plaques' develop as a consequence of systemic inflammation and are prone to inducing thrombosis. Vulnerable plaques most commonly have a large plaque burden with a well-formed necrotic core and thin fibrous cap and are metabolically active. Perivascular adipose tissue might, in some patients, be used as a surrogate for coronary inflammation and predict future risk of adverse cardiac events. Vulnerable plaques can be identified in their quiescent state, offering the potential for therapeutic passivation. In this Review, we describe the biological and compositional features of vulnerable plaques, the non-invasive and invasive diagnostic modalities to characterize vulnerable plaques, the prognostic utility of identifying vulnerable plaques, and the future studies needed to explore the value of intensified pharmacological and focal treatments of vulnerable plaques.

Radial Wall Strain Assessment From AI-Assisted Angiography: Feasibility and Agreement With OCT as Reference Standard

Background

High-strain spots in coronary arteries are associated with plaque vulnerability and predict future events. Artificial intelligence currently enables the calculation of radial wall strain (RWS) from coronary angiography (RWSAngio). This study aimed to determine the agreement between novel RWSAngio and RWS derived from optical coherence tomography (OCT) followed by finite element analysis, as the established reference standard (RWSOCT).

Methods

All lesions from a previous OCT study were enrolled. OCT was automatically coregistered with angiography. RWSAngio was computed as the relative luminal deformation throughout the cardiac cycle, whereas RWSOCT was analyzed using finite element analysis on OCT cross-sections at 1-mm intervals. The luminal deformation in the direction of minimal lumen diameter was used to derive RWSOCT, using the same definition as RWSAngio. The maximal RWSOCT and RWSAngio at healthy segments adjacent to the interrogated lesion were also analyzed.

Results

Finite element analysis was performed in 578 OCT cross-sections from 45 lesions stemming from 36 patients. RWSAngio showed good correlation and agreement with RWSOCT (r = 0.91; P < .001; Lin coefficient = 0.85). RWSAngio in atherosclerotic segments was significantly higher than that in healthy segments (12.6% [11.0, 16.0] vs 4.5% [2.9, 5.5], P < .001). The intraclass correlation coefficients for intra- and interobserver variability in repeated RWSAngio analysis were 0.92 (95% CI, 0.87-0.95) and 0.88 (95% CI, 0.81-0.92), respectively. The mean analysis time of RWSOCT and RWSAngio for each lesion was 95.0 ± 41.1 and 0.9 ± 0.1 minutes, respectively.

Conclusions

Radial wall strain from coronary angiography can be rapidly and easily computed solely from angiography, showing excellent agreement with strain derived from coregistered OCT. This novel and simple method might provide a cost-effective biomechanical assessment in large populations.

ANGPTL4 stabilizes atherosclerotic plaques and modulates the phenotypic transition of vascular smooth muscle cells through KLF4 downregulation

Atherosclerosis, the leading cause of death, is a vascular disease of chronic inflammation. We recently showed that angiopoietin-like 4 (ANGPTL4) promotes cardiac repair by suppressing pathological inflammation. Given the fundamental contribution of inflammation to atherosclerosis, we assessed the role of ANGPTL4 in the development of atherosclerosis and determined whether ANGPTL4 regulates atherosclerotic plaque stability. We injected ANGPTL4 protein twice a week into atherosclerotic Apoe-/- mice and analyzed the atherosclerotic lesion size, inflammation, and plaque stability. In atherosclerotic mice, ANGPTL4 reduced atherosclerotic plaque size and vascular inflammation. In the atherosclerotic lesions and fibrous caps, the number of α-SMA(+), SM22α(+), and SM-MHC(+) cells was higher, while the number of CD68(+) and Mac2(+) cells was lower in the ANGPTL4 group. Most importantly, the fibrous cap was significantly thicker in the ANGPTL4 group than in the control group. Smooth muscle cells (SMCs) isolated from atherosclerotic aortas showed significantly increased expression of CD68 and Krüppel-like factor 4 (KLF4), a modulator of the vascular SMC phenotype, along with downregulation of α-SMA, and these changes were attenuated by ANGPTL4 treatment. Furthermore, ANGPTL4 reduced TNFα-induced NADPH oxidase 1 (NOX1), a major source of reactive oxygen species, resulting in the attenuation of KLF4-mediated SMC phenotypic changes. We showed that acute myocardial infarction (AMI) patients with higher levels of ANGPTL4 had fewer vascular events than AMI patients with lower levels of ANGPTL4 (p < 0.05). Our results reveal that ANGPTL4 treatment inhibits atherogenesis and suggest that targeting vascular stability and inflammation may serve as a novel therapeutic strategy to prevent and treat atherosclerosis. Even more importantly, ANGPTL4 treatment inhibited the phenotypic changes of SMCs into macrophage-like cells by downregulating NOX1 activation of KLF4, leading to the formation of more stable plaques.

Cardiac computed tomographic imaging in cardio-oncology: An expert consensus document of the Society of Cardiovascular Computed Tomography (SCCT). Endorsed by the International Cardio-Oncology Society (ICOS)

Cardio-Oncology is a rapidly growing sub-specialty of medicine, however, there is very limited guidance on the use of cardiac CT (CCT) in the care of Cardio-Oncology patients. In order to fill in the existing gaps, this Expert Consensus statement comprised of a multidisciplinary collaboration of experts in Cardiology, Radiology, Cardiovascular Multimodality Imaging, Cardio-Oncology, Oncology and Radiation Oncology aims to summarize current evidence for CCT applications in Cardio-Oncology and provide practice recommendations for clinicians.

Identification of vulnerable non-culprit lesions by coronary computed tomography angiography in patients with chronic coronary syndrome and diabetes mellitus

Background

Among patients with diabetes mellitus (DM) and chronic coronary syndrome (CCS), non-culprit lesions (NCLs) are responsible for a substantial number of future major adverse cardiovascular events (MACEs). Thus, we aimed to establish the natural history relationship between adverse plaque characteristics (APCs) of NCLs non-invasively identified by coronary computed tomography angiography (CCTA) and subsequent MACEs in these patients.

Methods

Between January 2016 and January 2019, 523 patients with DM and CCS were included in the present study after CCTA and successful percutaneous coronary intervention (PCI). All patients were followed up for MACEs (the composite of cardiac death, myocardial infarction, and unplanned coronary revascularization) until January 2022, and the independent clinical event committee classified MACEs as indeterminate, culprit lesion (CL), and NCL-related. The primary outcome was MACEs arising from untreated NCLs during the follow-up. The association between plaque characteristics detected by CCTA and primary outcomes was determined by Marginal Cox proportional hazard regression.

Results

Overall, 1,248 NCLs of the 523 patients were analyzed and followed up for a median of 47 months. The cumulative rates of indeterminate, CL, and NCL-related MACEs were 2.3%, 14.5%, and 20.5%, respectively. On multivariate analysis, NCLs associated with recurrent MACEs were more likely to be characterized by a plaque burden >70% [hazard ratio (HR), 4.35, 95% confidence interval (CI): 2.92-6.44], a low-density non-calcified plaque (LDNCP) volume >30 mm³ (HR: 3.40, 95% CI: 2.07-5.56), a minimal luminal area (MLA) <4 mm² (HR: 2.30, 95% CI: 1.57-3.36), or a combination of three APCs (HR: 13.69, 95% CI: 9.34-20.12, p < 0.0001) than those not associated with recurrent MACEs. Sensitivity analysis regarding all indeterminate MACEs as NCL-related ones demonstrated similar results.

Conclusions

In DM patients who presented with CCS and underwent PCI, half of the MACEs occurring during the follow-up were attributable to recurrence at the site of NCLs. NCLs responsible for unanticipated MACEs were frequently characterized by a large plaque burden and LDNCP volume, a small MLA, or a combination of these APCs, as determined by CCTA.

The effect of plaque morphology, material composition and microcalcifications on the risk of cap rupture: A structural analysis of vulnerable atherosclerotic plaques

Background

The mechanical rupture of an atheroma cap may initiate a thrombus formation, followed by an acute coronary event and death. Several morphology and tissue composition factors have been identified to play a role on the mechanical stability of an atheroma, including cap thickness, lipid core stiffness, remodeling index, and blood pressure. More recently, the presence of microcalcifications (μCalcs) in the atheroma cap has been demonstrated, but their combined effect with other vulnerability factors has not been fully investigated.

Materials and methods

We performed numerical simulations on 3D idealized lesions and a microCT-derived human coronary atheroma, to quantitatively analyze the atheroma cap rupture. From the predicted cap stresses, we defined a biomechanics-based vulnerability index (VI) to classify the impact of each risk factor on plaque stability, and developed a predictive model based on their synergistic effect.

Results

Plaques with low remodeling index and soft lipid cores exhibit higher VI and can shift the location of maximal wall stresses. The VI exponentially rises as the cap becomes thinner, while the presence of a μCalc causes an additional 2.5-fold increase in vulnerability for a spherical inclusion. The human coronary atheroma model had a stable phenotype, but it was transformed into a vulnerable plaque after introducing a single spherical μCalc in its cap. Overall, cap thickness and μCalcs are the two most influential factors of mechanical rupture risk.

Conclusions

Our findings provide supporting evidence that high risk lesions are non-obstructive plaques with softer (lipid-rich) cores and a thin cap with μCalcs. However, stable plaques may still rupture in the presence of μCalcs.

Plaque histology and myocardial disease in sudden coronary death: the Fingesture study

AIMS

At least 50% of deaths due to coronary artery disease (CAD) are sudden cardiac deaths (SCDs), but the role of acute plaque complications on the incidence of sudden death in CAD is somewhat unclear. The present study aimed to investigate plaque histology and concomitant myocardial disease in sudden coronary death.

METHODS AND RESULTS

The study population is derived from the Fingesture study, which has collected data from 5869 consecutive autopsy-verified SCD victims in Northern Finland (population ≈600 000) between 1998 and 2017. In this substudy, histological examination of culprit lesions was performed in 600 SCD victims whose death was due to CAD. Determination of the cause of death was based on the combination of medical records, police reports, and autopsy data. Plaque histology was classified as either (i) plaque rupture or erosion, (ii) intraplaque haemorrhage, or (iii) stable plaque. The mean age of the study subjects was 64.9 ± 11.2 years, and 82% were male. Twenty-four per cent had plaque rupture or plaque erosion, 24% had an intraplaque haemorrhage, and 52% had a stable plaque. Myocardial hypertrophy was present in 78% and myocardial fibrosis in 93% of victims. The presence of myocardial hypertrophy or fibrosis was not associated with specific plaque histology.

CONCLUSION

Less than half of sudden deaths due to CAD had evidence of acute plaque complication, an observation which is contrary to historical perceptions. The prevalence of concomitant myocardial disease was high and independent of associated plaque morphology.

Simultaneous [18F]fluoride and gadobutrol enhanced coronary positron emission tomography/magnetic resonance imaging for in vivo plaque characterization

AIMS

18F-sodium fluoride ([18F]fluoride) and gadobutrol are promising probes for positron emission tomography (PET) and magnetic resonance imaging (MRI) characterizing coronary artery disease (CAD) activity. Unlike [18F]fluoride-PET/computed tomography (CT), the potential of PET/MR using [18F]fluoride and gadobutrol simultaneously, has so far not been evaluated. This study assessed feasibility and diagnostic potential of [18F]fluoride and gadobutrol enhanced dual-probe PET/MR in patients with CAD.

METHODS AND RESULTS

Twenty-one patients (age, 66.7 ± 6.7 years) with CAD scheduled for invasive coronary angiography (XCA) underwent simultaneous [18F]fluoride (mean activity/effective dose: 157.2 ± 29.7 MBq/3.77 ± 0.72 mSv) and gadobutrol enhanced PET/MR on an integrated PET/MRI (3 T) scanner. Optical coherence tomography (OCT) was used as reference. Target-to-background ratio (TBR, [18F]fluoride-PET) and contrast-to-noise ratio (CNR) values (MRI, gadobutrol) were calculated for each coronary segment. Previously suggested PET/CT-TBR thresholds for adverse coronary events were evaluated. High-risk plaques, i.e. calcified and non-calcified thin-cap fibroatheromas (TCFAs) were predominantly located in segments with a TBR >1.28 (P = 0.012). Plaques containing a lipid core on OCT, were more frequently detected in segments with a TBR >1.25 (P < 0.001). TBR values significantly correlated with maximum calcification thickness (P = 0.009), while fibrous cap thickness was significantly less in segments with a TBR >1.28 (P = 0.044). Above a TBR threshold of >1.28, CNR values significantly correlated with the presence of calcified TCFAs (P = 0.032).

CONCLUSION

Simultaneous [18F]fluoride and gadobutrol dual-probe PET/MRI is feasible in clinical practice and may facilitate the identification of high-risk patients. The combination of coronary MR-derived CNR values post gadobutrol and [18F]fluoride based TBR values may improve identification of high-risk plaque features.

Leukotriene A4 Hydrolase and Hepatocyte Growth Factor Are Risk Factors of Sudden Cardiac Death Due to First-Ever Myocardial Infarction

Patients at a high risk for sudden cardiac death (SCD) without previous history of cardiovascular disease remain a challenge to identify. Atherosclerosis and prothrombotic states involve inflammation and non-cardiac tissue damage that may play active roles in SCD development. Therefore, we hypothesized that circulating proteins implicated in inflammation and tissue damage are linked to the future risk of SCD. We conducted a prospective nested case–control study of SCD cases with verified myocardial infarction (N = 224) and matched controls without myocardial infarction (N = 224), aged 60 ± 10 years time and median time to event was 8 years. Protein concentrations (N = 122) were measured using a proximity extension immunoassay. The analyses revealed 14 proteins significantly associated with an increased risk of SCD, from which two remained significant after adjusting for smoking status, systolic blood pressure, BMI, cholesterol, and glucose levels. We identified leukotriene A4 hydrolase (LTA4H, odds ratio 1.80, corrected confidence interval (CIcorr) 1.02–3.17) and hepatocyte growth factor (HGF; odds ratio 1.81, CIcorr 1.06–3.11) as independent risk markers of SCD. Elevated LTA4H may reflect increased systemic and pulmonary neutrophilic inflammatory processes that can contribute to atherosclerotic plaque instability. Increased HGF levels are linked to obesity-related metabolic disturbances that are more prevalent in SCD cases than the controls.

Adhesion Molecules and Vulnerable Plaques – Promoters of Acute Coronary Syndromes

Biological factors that characterize extrinsic plaque vulnerability include various pro- and anti-inflammatory cytokines that contribute to the development and progression of atherosclerosis. Adhesion molecules are among the initiators of the atherosclerotic process, by mediation of endothelial inflammation. The soluble forms of these adhesion molecules have been identified in the circulatory blood, with an increased level in case of subjects with atherosclerotic lesions and higher levels in patients with acute coronary syndromes or vulnerable plaques. In addition, several authors have found a significant predictive capacity of these molecules in case of patients presenting with acute coronary and cerebrovascular events. The aim of this manuscript is to provide a short description of the role of adhesion molecules in the development and progression of atherosclerotic lesions towards acute coronary syndromes, as well as their capacity for predicting major adverse cardiovascular events in vulnerable cardiovascular patients.

Quantitative susceptibility mapping (QSM) of the cardiovascular system: challenges and perspectives

Quantitative susceptibility mapping (QSM) is a powerful, non-invasive, magnetic resonance imaging (MRI) technique that relies on measurement of magnetic susceptibility. So far, QSM has been employed mostly to study neurological disorders characterized by iron accumulation, such as Parkinson's and Alzheimer's diseases. Nonetheless, QSM allows mapping key indicators of cardiac disease such as blood oxygenation and myocardial iron content. For this reason, the application of QSM offers an unprecedented opportunity to gain a better understanding of the pathophysiological changes associated with cardiovascular disease and to monitor their evolution and response to treatment. Recent studies on cardiovascular QSM have shown the feasibility of a non-invasive assessment of blood oxygenation, myocardial iron content and myocardial fibre orientation, as well as carotid plaque composition. Significant technical challenges remain, the most evident of which are related to cardiac and respiratory motion, blood flow, chemical shift effects and susceptibility artefacts. Significant work is ongoing to overcome these challenges and integrate the QSM technique into clinical practice in the cardiovascular field.

Risk Stratification in Acute Coronary Syndrome by Comprehensive Morphofunctional Assessment With Optical Coherence Tomography

Background

Artificial intelligence enables simultaneous evaluation of plaque morphology and computational physiology from optical coherence tomography (OCT).

Objectives

This study sought to appraise the predictive value of major adverse cardiovascular events (MACE) by combined plaque morphology and computational physiology.

Methods

A total of 604 patients with acute coronary syndrome who underwent OCT imaging in ≥1 nonculprit vessel during index coronary angiography were retrospectively enrolled. A novel morphologic index, named the lipid-to-cap ratio (LCR), and a functional parameter to evaluate the physiologic significance of coronary stenosis from OCT, namely, the optical flow ratio (OFR), were calculated from OCT, together with classical morphologic parameters, like thin-cap fibroatheroma (TCFA) and minimal lumen area.

Results

The 2-year cumulative incidence of a composite of nonculprit vessel–related cardiac death, cardiac arrest, acute myocardial infarction, and ischemia-driven revascularization (NCV-MACE) at 2 years was 4.3%. Both LCR (area under the curve [AUC]: 0.826; 95% CI: 0.793-0.855) and OFR (AUC: 0.838; 95% CI: 0.806-0.866) were superior to minimal lumen area (AUC: 0.618; 95% CI: 0.578-0.657) in predicting NCV-MACE at 2 years. Patients with both an LCR of >0.33 and an OFR of ≤0.84 had significantly higher risk of NCV-MACE at 2 years than patients in whom at least 1 of these 2 parameters was normal (HR: 42.73; 95% CI: 12.80-142.60; P < 0.001). The combination of thin-cap fibroatheroma and OFR also identified patients at higher risk of future events (HR: 6.58; 95% CI: 2.83-15.33; P < 0.001).

Conclusions

The combination of LCR with OFR permits the identification of a subgroup of patients with 43-fold higher risk of recurrent cardiovascular events in the nonculprit vessels after acute coronary syndrome.

Effects of diagnostic ultrasound with cRGD-microbubbles on simultaneous detection and treatment of atherosclerotic plaque in ApoE−/− mice

Background

Atherosclerotic vulnerable plaque is the leading cause of acute fatal cardiovascular events. Thus, early rapid identification and appropriate treatment of atherosclerotic plaque maybe can prevent fatal cardiovascular events. However, few non–invasive molecular imaging techniques are currently available for the simultaneous detection and targeted treatment of atherosclerotic plaques. We hypothesized that diagnostic ultrasound (DU) combined with cyclic Arg-Gly-Asp-modified microbubbles (MB_R) could provide targeted imaging and dissolution of activated platelets to identify advanced atherosclerotic plaques and improve plaque instability.

Methods

Three mouse models, apolipoprotein E-deficient mice on a hypercholesterolemic diet (HCD) or normal chow diet and wild-type mice on an HCD were used. The most appropriate ultrasonic mechanical index (MI) was determined based on the expression of GP IIb/IIIa in sham, DU alone and DUMB_R-treated groups at MI values of 0.5, 1.5, and 1.9. The video intensity (VI) values, activated platelets and plaque instability were analyzed by ultrasound molecular imaging, scanning electron microscopy and histopathological methods.

Results

We found that the VI values of ultrasound molecular imaging of MB_R were positively correlated with plaque GP IIb/IIIa expression, vulnerability index and necrotic center / fiber cap ratio. 24 h after treatment at different MIs, compared with those of the other groups, both the VI values and GP IIb/IIIa expression were significantly reduced in MI 1.5 and MI 1.9 DUMB_R-treated groups. The plaque vulnerability index and necrotic center / fiber cap ratio were significantly decreased in MI 1.5-treated group, which may be due to targeted dissolution of activated platelets, with a reduction in von Willebrand factor expression.

Conclusion

DUMB_R targeting GP IIb/IIIa receptors could rapidly detect advanced atherosclerotic plaques and simultaneously give targeted therapy by dissolving activated and aggregated platelets. This technology may represent a novel approach for the simultaneous identification and treatment of atherosclerotic plaques.

The role of cardiac computed tomography in predicting adverse coronary events

Cardiac computed tomography (CCT) is now considered a first-line diagnostic test for suspected coronary artery disease (CAD) providing a non-invasive, qualitative, and quantitative assessment of the coronary arteries and pericoronary regions. CCT assesses vascular calcification and coronary lumen narrowing, measures total plaque burden, identifies plaque composition and high-risk plaque features and can even assist with hemodynamic evaluation of coronary lesions. Recent research focuses on computing coronary endothelial shear stress, a potent modulator in the development and progression of atherosclerosis, as well as differentiating an inflammatory from a non-inflammatory pericoronary artery environment using the simple measurement of pericoronary fat attenuation index. In the present review, we discuss the role of the above in the diagnosis of coronary atherosclerosis and the prediction of adverse cardiovascular events. Additionally, we review the current limitations of cardiac computed tomography as an imaging modality and highlight how rapid technological advancements can boost its capacity in predicting cardiovascular risk and guiding clinical decision-making.

Clinical Outcomes of Different Calcified Culprit Plaques in Patients with Acute Coronary Syndrome

Background: Previous studies have found that coronary artery calcification is closely associated with the occurrence of major adverse cardiac events (MACE). This study aimed to investigate the characteristics and clinical outcomes of different calcified plaques in patients with acute coronary syndrome (ACS) by using optical coherence tomography (OCT). Methods: 258 ACS patients with calcified culprit plaques who underwent OCT-guided stent implantation were enrolled. They were divided into three subtypes based on the calcified plaque morphology, including eruptive calcified nodules, calcified protrusion, and superficial calcific sheet. Results: Compared with superficial calcific sheet and calcified protrusion, eruptive calcified nodules had the greatest calcium burden and a higher rate of stent edge dissection (p < 0.001) and incomplete stent apposition (p < 0.001). In a median follow-up period of 2 years, 39 (15.1%) patients experienced MACE (a composite event of cardiac death, target-vessel myocardial infarction, ischemia-driven revascularization), with a significantly higher incidence in the eruptive calcified nodules group (32.1% vs. 10.1% vs. 13.0%, p = 0.001). A multivariate Cox analysis demonstrated that the eruptive calcified nodules (hazard ratio 3.14; 95% confidence interval, 1.64−6.02; p = 0.001) were an independent predictor of MACE. Conclusions: MACE occurred more frequently in ACS patients with eruptive calcified nodules, and the eruptive calcified nodules were an independent predictor of MACE.

Salvianolic Acid B Alleviates Myocardial Ischemia Injury by Suppressing NLRP3 Inflammasome Activation via SIRT1-AMPK-PGC-1α Signaling Pathway

Salvianolic acid B (SalB) has been extensively investigated in our laboratory for myocardial ischemia (MI) disease. This study mainly aimed to illustrate the relationship between SIRT1 and the therapeutic effect of SalB on MI in rats and hypoxia damage in H9c2 cells. Furthermore, whether the antagonism of NLRP3 by SalB in the injuries mentioned above is related to SIRT1-AMPK-PGC-1α pathway-mediated mitochondrial biogenesis was further investigated. In vivo, 24 h after MI surgery, we found that SalB effectively reduced ST-segment elevation, myocardial infarct size enlargement, cardiac injury markers, myocardial structural abnormalities, and myocardial apoptotic cells in MI injury rats. In vitro, after 4 h of hypoxia exposure, SalB alleviated cell injury, inhibited the production of ROS and IL-1β, and prevented the loss of mitochondrial membrane potential (MMP). Besides, SalB downregulated the critical components of the NLRP3 inflammasome and upregulated the SIRT1-AMPK-PGC-1α signaling pathway-related molecules in myocardial tissues and H9c2 cells. However, all the above protective effects of SalB on MI could be offset by EX527. Taken together, our findings indicated that SalB could attenuate MI injury by targeting NLRP3, which is at least partially dependent on the SIRT1/AMPK/PGC-1α signaling pathway.

High-Risk Coronary Plaque Features: A Narrative Review

Advances in coronary plaque imaging over the last few decades have led to an increased interest in the identification of novel high-risk plaque features that are associated with cardiovascular events. Existing practices focus on risk stratification and lipid monitoring for primary and secondary prevention of cardiac events, which is limited by a lack of assessment and treatment of vulnerable plaque. In this review, we summarize the multitude of studies that have identified plaque, haemodynamic and patient factors associated with risk of acute coronary syndrome. Future progress in multi-modal imaging strategies and in our understanding of high-risk plaque features could expand treatment options for coronary disease and improve patient outcomes.

2021 Jeffrey M. Hoeg Award Lecture: Defining the Role of Efferocytosis in Cardiovascular Disease: A Focus on the CD47 (Cluster of Differentiation 47) Axis

A key feature of atherogenesis is the accumulation of diseased and dying cells within the lesional necrotic core. While the burden of intraplaque apoptotic cells may be driven in part by an increase in programmed cell death, mounting evidence suggests that their presence may primarily be dictated by a defect in programmed cell removal, or efferocytosis. In this brief review, we will summarize the evidence suggesting that inflammation-dependent changes within the plaque render target cells inedible and reduce the appetite of lesional phagocytes. We will present the genetic causation studies, which indicate these phenomena promote lesion expansion and plaque vulnerability, and the interventional data which suggest that these processes can be reversed. Particular emphasis is provided related to the antiphagocytic CD47 (cluster of differentiation 47) do not eat me axis, which has emerged as a novel antiatherosclerotic translational target that is predicted to provide benefit independent of traditional cardiovascular risk factors.

Radiomics-Based Precision Phenotyping Identifies Unstable Coronary Plaques From Computed Tomography Angiography

OBJECTIVES

The aim of this study was to precisely phenotype culprit and nonculprit lesions in myocardial infarction (MI) and lesions in stable coronary artery disease (CAD) using coronary computed tomography angiography (CTA)-based radiomic analysis.

BACKGROUND

It remains debated whether any single coronary atherosclerotic plaque within the vulnerable patient exhibits unique morphology conferring an increased risk of clinical events.

METHODS

A total of 60 patients with acute MI prospectively underwent coronary CTA before invasive angiography and were matched to 60 patients with stable CAD. For all coronary lesions, high-risk plaque (HRP) characteristics were qualitatively assessed, followed by semiautomated plaque quantification and extraction of 1,103 radiomic features. Machine learning models were built to examine the additive value of radiomic features for discriminating culprit lesions over and above HRP and plaque volumes.

RESULTS

Culprit lesions had higher mean volumes of noncalcified plaque (NCP) and low-density noncalcified plaque (LDNCP) compared with the highest-grade stenosis nonculprits and highest-grade stenosis stable CAD lesions (NCP: 138.1 mm3 vs 110.7 mm3 vs 102.7 mm3; LDNCP: 14.2 mm3 vs 9.8 mm3 vs 8.4 mm3; both Ptrend < 0.01). In multivariable linear regression adjusted for NCP and LDNCP volumes, 14.9% (164 of 1,103) of radiomic features were associated with culprits and 9.7% (107 of 1,103) were associated with the highest-grade stenosis nonculprits (critical P < 0.0007) when compared with highest-grade stenosis stable CAD lesions as reference. Hierarchical clustering of significant radiomic features identified 9 unique data clusters (latent phenotypes): 5 contained radiomic features specific to culprits, 1 contained features specific to highest-grade stenosis nonculprits, and 3 contained features associated with either lesion type. Radiomic features provided incremental value for discriminating culprit lesions when added to a machine learning model containing HRP and plaque volumes (area under the receiver-operating characteristic curve 0.86 vs 0.76; P = 0.004).

CONCLUSIONS

Culprit lesions and highest-grade stenosis nonculprit lesions in MI have distinct radiomic signatures compared with lesions in stable CAD. Within the vulnerable patient may exist individual vulnerable plaques identifiable by coronary CTA-based precision phenotyping.

Determinants of Non-calcified Low-Attenuation Coronary Plaque Burden in Patients Without Known Coronary Artery Disease: A Coronary CT Angiography Study

Background

Although epicardial adipose tissue (EAT) is associated with coronary artery disease (CAD), it is unclear whether EAT volume (EAV) can be used to diagnose high-risk coronary plaque burden associated with coronary events. This study aimed to investigate (1) the prognostic impact of low-attenuation non-calcified coronary plaque (LAP) burden on patient level analysis, and (2) the association of EAV with LAP volume in patients without known CAD undergoing coronary computed tomography angiography (CCTA).

Materials and Methods

This retrospective study consisted of 376 patients (male, 57%; mean age, 65.2 ± 13 years) without known CAD undergoing CCTA. Percent LAP volume (%LAP, <30 HU) was calculated as the LAP volume divided by the vessel volume. EAT was defined as adipose tissue with a CT attenuation value ranging from −250 to −30 HU within the pericardial sac. The primary endpoint was a composite event of death, non-fatal myocardial infarction, and unstable angina and worsening symptoms requiring unplanned coronary revascularization >3 months after CCTA. The determinants of %LAP (Q4) were analyzed using a multivariable logistic regression model.

Results

During the follow-up period (mean, 2.2 ± 0.9 years), the primary endpoint was observed in 17 patients (4.5%). The independent predictors of the primary endpoint were %LAP (Q4) (hazard ratio [HR], 3.05; 95% confidence interval [CI], 1.09–8.54; p = 0.033] in the Cox proportional hazard model adjusted by CAD-RADS category. Cox proportional hazard ratio analysis demonstrated that %LAP (Q4) was a predictor of the primary endpoint, independnet of CAD severity, Suita score, EAV, or CACS. The independent determinants of %LAP (Q4) were CACS ≥218.3 (p < 0.0001) and EAV ≥125.3 ml (p < 0.0001). The addition of EAV to CACS significantly improved the area under the curve (AUC) to identify %LAP (Q4) than CACS alone (AUC, EAV + CACS vs. CACS alone: 0.728 vs. 0.637; p = 0.013).

Conclusions

CCTA-based assessment of EAV, CACS, and LAP could help improve personalized cardiac risk management by administering patient-suited therapy.