Concomitant Coronary Atheroma Regression and Stabilization in Response to Lipid-Lowering Therapy

Translocator Protein 18 kDa Tracer 18F-FDPA PET/CTA Imaging for the Evaluation of Inflammation in Vulnerable Plaques

Inflammation induced by activated macrophages within vulnerable atherosclerotic plaques (VAPs) constitutes a significant risk factor for plaque rupture. Translocator protein (TSPO) is highly expressed in activated macrophages. This study investigated the effectiveness of TSPO radiotracers, 18F-FDPA, in detecting VAPs and quantifying plaque inflammation in rabbits. 18 New Zealand rabbits were divided into 3 groups: sham group A, VAP model group B, and evolocumab treatment group C. 18F-FDPA PET/CTA imaging was performed at 12, 16, and 24 weeks in all groups. Optical coherence tomography (OCT) was performed on the abdominal aorta at 24 weeks. The VAP was defined through OCT images, and ex vivo aorta PET imaging was also performed at 24 weeks. The SUVmax and SUVmean of 18F-FDPA were measured on the target organ, and the target-to-background ratio (TBRmax) was calculated as SUVmax/SUVblood pool. The arterial sections of the isolated abdominal aorta were analyzed by HE staining, CD68 and TSPO immunofluorescence staining, and TSPO Western blot. The results showed that at 24 weeks, the plaque TBRmax of 18F-FDPA in group B was significantly higher than in groups A and C. Immunofluorescence staining of CD68 and TSPO, as well as Western blot, confirmed the increased expression of macrophages and TSPO in the corresponding regions of group B. HE staining revealed an increased presence of the lipid core, multiple foam cells, and inflammatory cell infiltration in the area with high 18F-FDPA uptake. This indicates a correlation between 18F-FDPA uptake, inflammation severity, and VAPs. The TSPO-targeted tracer 18F-FDPA shows specific uptake in macrophage-rich regions of atherosclerotic plaques, making it a valuable tool for assessing inflammation in VAPs.

Atherosclerotic plaque stabilization and regression: a review of clinical evidence

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

Drug intervention as an emerging concept for secondary prevention in patients with coronary disease

Non-culprit lesion-related coronary events are a significant concern in patients with coronary artery disease (CAD) undergoing coronary intervention. Since several studies using intra-coronary imaging modalities have reported a high prevalence of vulnerable plaques in non-culprit lesions at the initial coronary event, the immediate stabilization of these plaques by intensive pharmacological regimens may contribute to the reduction in the adverse events. Although current treatment guidelines recommend the titration of statin and other drugs to attain the treatment goal of low-density lipoprotein cholesterol (LDL-C) level in patients with CAD, the early prescription of strong LDL-C lowering drugs with more intensive regimen may further reduce the incidence of recurrent cardiovascular events. In fact, several studies with intensive regimen have demonstrated a higher percentage of patients with the attainment of LDL-C treatment goal in the early phase following discharge. In addition to many imaging studies showing plaque stabilization by LDL-C lowering drugs, several recent reports have shown the efficacy of early statin and proprotein convertase subtilisin/kexin type 9 inhibitors on the immediate stabilization of non-culprit coronary plaques. To raise awareness regarding this important concept of immediate plaque stabilization and subsequent reduction in the incidence of recurrent coronary events, the term 'Drug Intervention' has been introduced and gradually applied in the clinical field, although a clear definition is lacking. The main target of this concept is patients with acute coronary syndrome as a higher prevalence of vulnerable plaques in non-culprit lesions in addition to the worse clinical outcomes has been reported in recent imaging studies. In this article, we discuss the backgrounds and the concept of drug intervention.

The cytoplasmic sensor, the AIM2 inflammasome: A precise therapeutic target in vascular and metabolic diseases

Cardio-cerebrovascular diseases encompass pathological changes in the heart, brain and vascular system, which pose a great threat to health and well-being worldwide. Moreover, metabolic diseases contribute to and exacerbate the impact of vascular diseases. Inflammation is a complex process that protects against noxious stimuli but is also dysregulated in numerous so-called inflammatory diseases, one of which is atherosclerosis. Inflammation involves multiple organ systems and a complex cascade of molecular and cellular events. Numerous studies have shown that inflammation plays a vital role in cardio-cerebrovascular diseases and metabolic diseases. The absent in melanoma 2 (AIM2) inflammasome detects and is subsequently activated by double-stranded DNA in damaged cells and pathogens. With the assistance of the mature effector molecule caspase-1, the AIM2 inflammasome performs crucial biological functions that underpin its involvement in cardio-cerebrovascular diseases and related metabolic diseases: The production of interleukin-1 beta (IL-1β), interleukin-18 (IL-18) and N-terminal pore-forming Gasdermin D fragment (GSDMD-N) mediates a series of inflammatory responses and programmed cell death (pyroptosis and PANoptosis). Currently, several agents have been reported to inhibit the activity of the AIM2 inflammasome and have the potential to be evaluated for use in clinical settings. In this review, we systemically elucidate the assembly, biological functions, regulation and mechanisms of the AIM2 inflammasome in cardio-cerebrovascular diseases and related metabolic diseases and outline the inhibitory agents of the AIM2 inflammasome as potential therapeutic drugs.

Impact of changes in Achilles tendon thickening on cardiovascular events in patients with familial hypercholesterolemia

Background

Achilles tendon thickening (ATT) can be ameliorated by lowering low-density lipoprotein (LDL) levels in patients with familial hypercholesterolemia (FH). The Japan Atherosclerosis Society (JAS) defines ATT as ≥8.0 mm in males and ≥7.5 mm in females. We aimed to determine the clinical impact of changes in ATT on the development of major adverse cardiovascular events (MACE).

Methods

Patients with clinically diagnosed heterozygous FH (HeFH) (N = 1273; 614 males, 659 females) with ATT data from X-ray were assessed. Patients were divided into four groups: patients without ATT from baseline until follow-up (group 1), patients without ATT at baseline but developed ATT at follow-up (group 2), patients with ATT at baseline but regressed at follow-up (group 3), and patients with ATT from baseline until follow-up (group 4). Cox proportional hazard models were used to assess the factors associated with MACE, including cardiovascular death and any coronary events.

Results

On follow-up (median: 10.9 years), 142 MACEs were observed, and the median ATT regressed from 7.8 to 7.6 mm. Changes in ATT were significantly associated with the occurrence of MACE in all groups, when compared to group 1 (hazard ratio [HR]: 2.73; 95 % confidence interval [CI]: 1.33-4.13 [p < 0.001], HR: 2.18, 95 % CI: 1.08-3.28, [p < 0.001], HR: 6.34, 95 % CI: 3.10-9.58, [p < 0.001], in groups 2, 3, and 4, respectively).

Conclusions

Assessing ATT has diagnostic value and allows for risk stratification among patients with HeFH.

Strike early-strike strong lipid-lowering strategy with PCSK9i in ACS patients. Real-world evidence from AT-TARGET-IT registry

AIMS

No data are available on early initiation of proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) in patients with acute coronary syndrome (ACS) in real-world. This study investigates the effects of PCSK9i started at time of ACS hospitalization on lipid control and major CV events in real-world.

METHODS

The lipid control outcome was the percentage of patients reaching the LDL-C target of < 55 mg/dL at first lipid control. The clinical outcome was the incidence of composite major CV events (all cause death, non-fatal MI, non-fatal stroke, and ischemia-driven revascularization) during follow-up in relation to quartiles of LDL-C at first lipid control.

RESULTS

We included 771 patients with ACS from AT-TARGET-IT registry, receiving PCSK9i prescription during hospitalization or at discharge. Median LDL-C was 137 mg/dL and decreased to 43 mg/dL at first lipid control. 527 (68.3%) patients achieved LDL-C target at the first lipid control at a median time of 37 days from hospitalization; of them, 404 (76.8%) were discharged on statin plus ezetimibe background therapy. Event curves through a median follow-up of 11 months across quartiles of LDL-C showed a stepwise lower risk of 4P-MACE, 3P-MACE, all-cause mortality, and ischemia-driven revascularization in lower quartile of LDL-C values at first lipid control (<23 mg/dL) and in patients reaching LDL-C <55 mg/dL.

CONCLUSIONS

Intensive and early lipid-lowering therapy using PCSK9i in patients with ACS (strike early strike strong strategy) is safe and effective in clinical practice and associated with a reduction of residual CV risk.

Predictive Value of Plasma PCSK9 Levels for Degree of Atherosclerosis and Major Adverse Cardiovascular and Cerebrovascular Events in Older Adult Patients with Non-Alcoholic Fatty Liver Disease

Purpose

This study investigated the influence of plasma proprotein convertase subtilisin/kexin 9 (PCSK9) levels on the degree of atherosclerosis and major adverse cardiovascular and cerebrovascular events (MACCE) in older adults with non-alcoholic fatty liver disease.

Methods

The degree of atherosclerosis severity was assessed by the standard Gensini score quartile method. According to the degree of atherosclerosis, patients were divided into mild (0-24 points; n=84), moderate (25-53 points; n=86), and severe groups (≥54 points; n=84) and then categorized as MACCE (n=30) or non-MACCE (n=224) according to 6-month follow-up data. The patients' age, sex, smoking history, medical history, and early morning fasting venous blood, for measuring biochemical indexes, were collected. Clinical data were compared between groups and the relationship between Gensini scores and PCSK9 was evaluated.

Results

Compared with the mild group, the moderate and severe groups had higher high-sensitivity C-reactive protein(hs-CRP), PCSK9, triglycerides(TG), low-density lipoprotein cholesterol (LDL-C), and lipoprotein(a)[Lp(a)] levels and lower high-density lipoprotein cholesterol(HDL-C) levels (all P<0.05). Moreover, PCSK9 positively correlated with Gensini scores (r=0.657, P<0.01). The MACCE and non-MACCE groups had significantly different ages, statin use, Gensini scores, PCSK9, and LDL-C (all P<0.05). Multi-factorial Cox risk regression analysis showed the Gensini score (HR=1.018, 95% CI: 1.006~1.029) and PCSK9 (HR=1.147, 95% CI: 1.038~1.287) were independent risk factors for MACCE.

Conclusion

The Gensini score and PCSK9 levels can be used as predictive indicators for the degree of illness and occurrence of MACCE in older NAFLD patients.

Intracoronary imaging to guide percutaneous coronary intervention: from evidence to guidelines

Despite notable advances in devices and techniques, percutaneous coronary intervention (PCI) is still affected by a substantial number of complications and failure rates. Over the years, the use of intracoronary imaging (ICI) has dramatically improved the understanding of mechanical and technical factors related to successful and failed PCI, becoming a mainstay in complex trans-catheter interventions. However, ICI modalities are invasive, time-consuming, and costly, and a net clinical benefit needs to be shown in order to recommend their routine use in clinical practice. In the past, the lack of evidence from randomized trials has been reflected in the scepticism shown by international guidelines. The recent publication of large randomized clinical trials conducted worldwide has provided new evidence regarding the clinical usefulness of ICI guidance in PCI. The consistent reduction of adverse events achieved in these trials, also demonstrated in an updated meta-analysis, suggested that the use of ICI in PCI is compelling to achieve optimal technical results and better outcomes, especially in complex high-risk interventions. Also considering the burden of information provided by ICI on coronary artery disease, looking from the inside seems today an opportunity that modern cardiology cannot ignore anymore.

Editor-in-Chief's Top Picks From 2023

Each week, I record audio summaries for every paper in JACC, as well as an issue summary. This process has become a true labor of love due to the time they require, but I am motivated by the sheer number of listeners (16M+), and it has allowed me to familiarize myself with every paper that we publish. Thus, I have selected the top 100 papers (Original Investigations, Review Articles, Society Documents, and the Global Burden of Diseases) from distinct specialties each year. In addition to my personal choices, I have included papers that have been the most accessed or downloaded on our websites, as well as those selected by the JACC Editorial Board members. In order to present the full breadth of this important research in a consumable fashion, we will present these abstracts in this issue of JACC, as well as their Central Illustrations∗ and podcasts. The highlights comprise the following sections: Aorta; Basic and Translational Science; Cardiac Failure, Myocarditis, and Pericarditis; Cardiomyopathies and Genetics; Congenital Heart Disease; Coronary, Peripheral, and Structural Interventions; Coronavirus; Health Promotion and Preventive Cardiology; Imaging; Metabolic and Lipid Disorders; Neurovascular Disease and Dementia; Rhythm Disorders and Thromboembolism; and Valvular Heart Disease.1-104 ∗ To view the full manuscript, including the full-sized Central Illustration, please refer to the original publication in JACC.

Monoclonal antibodies for dyslipidemia in adults: a focus on vulnerable patients groups

INTRODUCTION

Dyslipidemia significantly contributes to atherosclerotic cardiovascular disease (ASCVD). Patients with lipid-rich vulnerable plaques are particularly susceptible to cardiovascular complications. Despite available lipid-lowering therapies (LLTs), challenges in effective lipid management remain.

AREAS COVERED

This article reviews monoclonal antibody (mAb) therapy in dyslipidemia, particularly focusing on vulnerable plaques and patients. We have reviewed the definitions of vulnerable plaques and patients, outlined the efficacy of traditional LLTs, and discussed in-depth the mAbs targeting PCSK9. We extensively discuss the potential mechanisms, intracoronary imaging, and clinical evidence of PCSK9mAbs in vulnerable plaques and patients. A brief overview of promising mAbs targeting other targets such as ANGPTL3 is also provided.

EXPERT OPINION

Research consistently supports the potential of mAb therapies in treating adult dyslipidemia, particularly in vulnerable patients. PCSK9mAbs are effective in regulating lipid parameters, such as LDL-C and Lp(a), and exhibit anti-inflammatory and anti-thrombotic properties. These antibodies also maintain endothelial and smooth muscle health, contributing to the stabilization of vulnerable plaques and reduction in adverse cardiovascular events. Future research aims to further understand PCSK9 and other targets like ANGPTL3, focusing on vulnerable groups. Overall, mAbs are emerging as a promising and superior approach in dyslipidemia management and cardiovascular disease prevention.

Characteristics of Coronary Atherosclerosis Related to Plaque Burden Regression During Treatment With Alirocumab: The ARCHITECT Study

BACKGROUND

Intensive lipid-lowering therapy may induce coronary atherosclerosis regression. Nevertheless, the factors underlying the effect of lipid-lowering therapy on disease regression remain poorly characterized. Our aim was to determine which characteristics of atherosclerotic plaque are associated with a greater reduction in coronary plaque burden (PB) after treatment with alirocumab in patients with familial hypercholesterolemia.

METHODS

The ARCHITECT study (Effect of Alirocumab on Atherosclerotic Plaque Volume, Architecture and Composition) is a phase IV, open-label, multicenter, single-arm clinical trial to assess the effect of the treatment with alirocumab for 78 weeks on the coronary atherosclerotic PB and its characteristics in subjects with familial hypercholesterolemia without clinical atherosclerotic cardiovascular disease. Participants underwent a coronary computed tomographic angiography at baseline and a final one at 78 weeks. Every patient received alirocumab 150 mg subcutaneously every 14 days in addition to high-intensity statin therapy.

RESULTS

One hundred and four patients were enrolled. Median age was 53.3 (46.2-59.4) years and 54 were women (51.9%). The global coronary PB changed from 34.6% (32.5%-36.8%) at entry to 30.4% (27.4%-33.4%) at follow-up, which is -4.6% (-7.7% to -1.9%; P<0.001) reduction. A decrease in the percentage of unstable core (fibro-fatty+necrotic plaque; from 14.1 [7.9-22.3] to 8.0 [6.4-10.6]; -6.6%; P<0.001) was found. A greater PB (β, 0.36 [0.13-0.59]; P=0.002) and a higher proportion of unstable core (β, 0.15 [0.08-0.22]; P<0.001) were significantly related to PB regression.

CONCLUSIONS

Treatment with alirocumab in addition to high-intensity statin therapy might produce a greater PB regression in patients with familial hypercholesterolemia with higher baseline PB and in those with larger unstable core. Further studies are needed to corroborate the hypothesis raised by these results.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT05465278.