Morphological Characteristics of Eroded Plaques with Noncritical Coronary Stenosis: An Optical Coherence Tomography Study

Predicting plaque regression based on plaque characteristics identified by optical coherence tomography: A retrospective study

BACKGROUND

Atherosclerosis is a lipid-driven, systemic immune-inflammatory disease characterized by the accumulation of plaque within the arterial walls. Plaque regression can occur following appropriate treatment interventions. Optical coherence tomography (OCT), a high-resolution imaging modality, is frequently employed to assess plaque morphology. This study aims to explore the correlation between plaque characteristics identified using OCT, particularly macrophage infiltration, and subsequent plaque regression.

METHODS

In this retrospective study, data from 112 individuals with coronary artery plaques, who underwent OCT imaging at our hospital, between June 2019 and June 2024, were evaluated. Plaques were classified as lipid-rich, fibrous, or calcified based on the initial OCT findings. Macrophage infiltration levels within each plaque type were quantified. After one year of follow-up, repeat OCT imaging was performed to evaluate plaque regression. Statistical analyses were conducted to assess the relationship between initial plaque characteristics and regression outcomes.

RESULTS

Plaques that underwent regression were more commonly lipid-rich and exhibited higher levels of macrophage infiltration compared to those without regression. Multivariate analysis identified the histological inflammation score (HIS) as an independent factor influencing plaque regression.

CONCLUSION

Macrophage-rich plaques, as detected by OCT, are significant predictors of plaque regression. The identification of vulnerable plaque features through OCT can enhance the early diagnosis and treatment strategies for atherosclerotic cardiovascular disease.

Comparison and identification of human coronary plaques with/without erosion using patient-specific optical coherence tomography-based fluid-structure interaction models: a pilot study

Plaque erosion (PE) with secondary thrombosis is one of the key mechanisms of acute coronary syndrome (ACS) which often leads to drastic cardiovascular events. Identification and prediction of PE are of fundamental significance for disease diagnosis, prevention and treatment. In vivo optical coherence tomography (OCT) data of eight eroded plaques and eight non-eroded plaques were acquired to construct three-dimensional fluid-structure interaction models and obtain plaque biomechanical conditions for investigation. Plaque stenosis severity, plaque burden, plaque wall stress (PWS) and strain (PWSn), flow shear stress (FSS), and ΔFSS (FSS variation in time) were extracted for comparison and prediction. A logistic regression model was used to predict plaque erosion. Our results indicated that the combination of mean PWS and mean ΔFSS gave best prediction (AUC = 0.866, 90% confidence interval (0.717, 1.0)). The best single predictor was max ΔFSS (AUC = 0.819, 90% confidence interval (0.624, 1.0)). The average of maximum FSS values from eroded plaques was 76% higher than that from the non-eroded plaques (127.96 vs. 72.69 dyn/cm2) while the average of mean FSS from erosion sites of the eight eroded plaques was 48.6% higher than that from sites without erosion (71.52 vs. 48.11 dyn/cm2). The average of mean PWS from plaques with erosion was 22.83% lower than that for plaques without erosion (83.2 kPa vs. 107.8 kPa). This pilot study suggested that combining plaque stress, strain and flow shear stress could help better identify patients with potential plaque erosion, enabling possible early intervention therapy. Further studies are needed to validate our findings.

Significance of myeloperoxidase, pentraxin-3 and soluble urokinase plasminogen activator receptor determination in patients with moderate carotid artery stenosis

We investigated serum concentrations of specific inflammatory parameters in patients with significant carotid artery stenosis (CAS) of 50-99%, with an additional focus on patients with moderate stenosis (50-69%), in terms of both symptomatic status and plaque morphology, to determine whether there are certain parameters that can be associated with plaque instability before the progression of CAS to a high degree. The study included 119 CAS patients, 29 of whom had moderate stenosis, and 46 controls. Ultrasonography of the carotid arteries was performed using color flow Doppler and B-mode duplex ultrasound, and serum inflammatory parameters were measured using commercially available enzyme immunoassays. When comparing patients with 50-99% stenosis, only serum amyloid A (SAA) was higher in symptomatic patients, while in the group of patients with 50-69% stenosis, myeloperoxidase (MPO) was higher and pentraxin-3 (PTX-3) was lower in symptomatic compared to asymptomatic patients, and soluble urokinase plasminogen activator receptor (suPAR) was higher in patients with carotid plaque of unstable compared to stable morphology. Our results suggest that the importance of different inflammatory parameters in patients with moderate CAS is not the same as in CAS patients in general, and therefore their separate investigation in patients with high and moderate stenosis may be beneficial. SAA has the potential to be further considered in research to predict CAS symptom risk. There is a possibility that MPO and PTX-3 play a role in the development of CAS symptoms originating from less stenotic plaques and that suPAR is involved in the destabilisation of such plaques.

The Characteristics of Coronary Artery Lesions in COVID-19 Infected Patients With Coronary Artery Disease: An Optical Coherence Tomography Study

COVID-19 may predispose patients to cardiac injuries but whether COVID-19 infection affects the morphological features of coronary plaques to potentially influence the outcome of patients with coronary artery disease (CAD) remains unknown. By using optical coherence tomography (OCT), this study compared the characteristics of coronary plaque in patients with CAD with/without COVID-19 infection. The 206 patients were divided into 2 groups. The COVID-19 group had 113 patients between December 7, 2022, and March 31, 2023, who received OCT assessment after China decided to lift the restriction on COVID-19 and had a history of COVID-19 infection. The non-COVID-19 group had 93 patients without COVID-19 infection who underwent OCT before December 7, 2022. The COVID-19 group demonstrated a higher incidence of plaque ruptures (53.1% vs 38.7%, p = 0.039), erosions (28.3% vs 11.8%, p = 0.004), fibrous (96.5% vs 89.2%, p = 0.041) and diffuse lesions (73.5% vs 50.5%, p <0.001) compared with the non-COVID-19 group, whereas non-COVID-19 group exhibited a higher frequency of cholesterol crystals (83.9% vs 70.8%, p = 0.027), deep calcifications (65.6% vs 51.3%, p = 0.039) and solitary lesions (57.0% vs 34.5%, p = 0.001). Kaplan-Meier survival analysis revealed a significantly lower major adverse cardiac events-free probability in the COVID-19 group (91.6% vs 95.5%, p = 0.006) than in the non-COVID-19 group. In conclusion, OCT demonstrated that COVID-19 infection is associated with coronary pathological changes such as more plaque ruptures, erosions, fibrosis, and diffuse lesions. Further, COVID-19 infection is associated with a higher propensity for acute coronary events and a higher risk of major adverse cardiac events in patients with CAD.

Precision Medicine in Acute Coronary Syndromes

Nowadays, current guidelines on acute coronary syndrome (ACS) provide recommendations mainly based on the clinical presentation. However, greater attention is being directed to the specific pathophysiology underlying ACS, considering that plaque destabilization and rupture leading to luminal thrombotic obstruction is not the only pathway involved, albeit the most recognized. In this review, we discuss how intracoronary imaging and biomarkers allow the identification of specific ACS endotypes, leading to the recognition of different prognostic implications, tailored management strategies, and new potential therapeutic targets. Furthermore, different strategies can be applied on a personalized basis regarding antithrombotic therapy, non-culprit lesion revascularization, and microvascular obstruction (MVO). With respect to myocardial infarction with non-obstructive coronary arteries (MINOCA), we will present a precision medicine approach, suggested by current guidelines as the mainstay of the diagnostic process and with relevant therapeutic implications. Moreover, we aim at illustrating the clinical implications of targeted strategies for ACS secondary prevention, which may lower residual risk in selected patients.

Morphological characteristics of in-stent restenosis with different degrees of area stenosis: an optical coherence tomography study

The morphological characteristics of in-stent restenosis (ISR) in relation to varying degrees of area stenosis have not been comprehensively examined. This study aimed to explore the tissue characteristics of patients experiencing ISR with different degrees of area stenosis through the utilization of optical coherence tomography (OCT). In total, 230 patients with ISR who underwent OCT were divided into the following three groups: area stenosis (AS) < 70% (n = 26); 70-80% (n = 119) and AS ≥ 80% (n = 85). Among the 230 patients, the clinical presentation as stable angina was 61.5% in AS < 70%, followed by 47.2% in 70% < AS ≤ 80%, and 31.8% in AS ≥ 80% (P = 0.010). The OCT findings showed that heterogeneous neointima, ISNA, LRP, neointima rupture, TCFA-like pattern, macrophage infiltration, red and white thrombus was more common with AS increased. Ordinal logistic regression analysis showed that higher AS was associated with previous dyslipidemia (odds ratio [OR], 4.754; 95% confidence interval [CI], 1.419-15.927, P = 0.011), neointimal rupture (OR: 3.640; 95% CI, 1.169-11.325, P = 0.026), red thrombus (OR: 4.482; 95% CI, 1.269-15.816, P = 0.020) and white thrombus (OR: 5.259; 95% CI, 1.660-16.659, P = 0.005). Patients with higher degrees of area stenosis in the context of ISR exhibited a greater number of discernible morphological characteristics as identified through OCT analysis. Furthermore, previous dyslipidemia, neointimal rupture, white thrombus and red thrombus were highly associated with and the progression of ISR lesions.

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

AIMS

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Comparison of Cell-based and Nanoparticle-based Therapeutics in Treating Atherosclerosis

Today, cardiovascular diseases are among the biggest public health threats worldwide. Atherosclerosis, a chronic inflammatory disease with complex aetiology and pathogenesis, predispose many of these conditions, including the high mortality rate-causing ischaemic heart disease and stroke. Nevertheless, despite the alarming prevalence and absolute death rate, established treatments for atherosclerosis are unsatisfactory in terms of efficacy, safety, and patient acceptance. The rapid advancement of technologies in healthcare research has paved new treatment approaches, namely cell-based and nanoparticle-based therapies, to overcome the limitations of conventional therapeutics. This paper examines the different facets of each approach, discusses their principles, strengths, and weaknesses, analyses the main targeted pathways and their contradictions, provides insights on current trends as well as highlights any unique mechanisms taken in recent years to combat the progression of atherosclerosis.

Plaque Erosion: A Distinctive Pathological Mechanism of Acute Coronary Syndrome

Plaque erosion (PE) is one of the most important pathological mechanisms underlying acute coronary syndrome (ACS). The incidence of PE is being increasingly recognized owing to the development and popularization of intracavitary imaging. Unlike traditional vulnerable plaques, eroded plaques have unique pathological characteristics. Moreover, recent studies have revealed that there are differences in the physiopathological mechanisms, biomarkers, and clinical outcomes between PE and plaque rupture (PR). Accurate diagnosis and treatment of eroded plaques require an understanding of the pathogenesis of PE. In this review, we summarize recent scientific discoveries of the pathological characteristics, mechanisms, biomarkers, clinical strategies, and prognosis in patients with PE.