Evidence of an anti-inflammatory effect of PCSK9 inhibitors within the human atherosclerotic plaque

Association between Pericarotid Fat Density and Positive Remodeling in Patients with Carotid Artery Stenosis

Background/Objectives: The underlying mechanism of the potential involvement of inflammatory crosstalk between pericarotid fat and vascular layers in atherosclerosis pathogenesis is unclear. We investigated the association between pericarotid fat density and positive remodeling and inflammatory markers in carotid stenosis. We hypothesized that pericarotid fat density might serve as a marker of plaque inflammation in a clinical setting. Methods: We evaluated the stenosis degree and pericarotid fat density in 258 patients with carotid plaques. Plaque composition was examined, and the correlation between pericarotid fat density and expansive remodeling was investigated. Pearson's product-moment correlation coefficient was used to examine the relationship between pericarotid fat density and the expansive remodeling ratio. We also evaluated the relationship of pericarotid fat density with plaque composition, degree of stenosis, and macrophage and microvessel counts by. The subgroup analysis compared these factors between symptomatic mild carotid stenosis. Results: The pericarotid fat density was -63.0 ± 11.1 HU. The carotid fat densities were -56.8 ± 10.4 HU in symptomatic and -69.2 ± 11.4 HU in asymptomatic lesions. The pericarotid fat density values in intraplaque hemorrhage, lipid-rich necrotic core, and fibrous plaque were -51.6 ± 10.4, -59.4 ± 12.8, and -74.2 ± 8.4 HU, respectively. Therefore, the expansive remodeling ratio was 1.64 ± 0.4. Carotid fat density and expansive remodeling ratio were correlated. Immunohistochemistry showed high macrophage and microvessel levels (143.5 ± 61.3/field and 121.2 ± 27.7/field, respectively). In symptomatic mild carotid stenosis, pericarotid fat density was correlated with other inflammatory factors. The pericarotid fat density and expansive remodeling ratio (2.08 ± 0.21) were high in mild stenosis (-50.1 ± 8.4 HU). Conclusions: Pericarotid fat and intraplaque components were well correlated. Carotid fat density may be a marker of plaque inflammation in carotid plaques.

Early Management of Blood Lipid Levels with Non-Statin Lipid-Lowering Drugs in Acute Coronary Syndrome: A Mini Review

Acute coronary syndrome (ACS) remains a major cause of morbidity and mortality, despite many improvements in its prevention and management. Lipid management is an important aspect of secondary prevention after ACS. Previous studies indicate that the early use of intensive statin therapy in patients with ACS may alleviate the risk of recurrent cardiovascular events and mortality. However, many patients do not reach the target low-density lipoprotein cholesterol (LDL-C) level of < 55 mg/dL with statin monotherapy, and muscle-related adverse effects caused by statins hinder adherence to treatment. Novel non-statin agents are recommended for patients who cannot achieve the target LDL-C levels with high-intensity statin therapy and those with statin intolerance. The combination of statins and non-statins may synergistically affect intensively lowering LDL-C through different mechanisms, which could lead to better cardiovascular outcomes than statin monotherapy. However, it remains uncertain whether the early use of combination lipid-lowering therapy is more beneficial. The present review summarizes the benefits of intensive statin monotherapy and their early combination with non-statin medications including ezetimibe, PCSK9 inhibitors, inclisiran, and bempedoic acid (BDA) in the management of ACS.

The Influence of Metabolic Risk Factors on the Inflammatory Response Triggered by Myocardial Infarction: Bridging Pathophysiology to Treatment

Myocardial infarction (MI) sets off a complex inflammatory cascade that is crucial for effective cardiac healing and scar formation. Yet, if this response becomes excessive or uncontrolled, it can lead to cardiovascular complications. This review aims to provide a comprehensive overview of the tightly regulated local inflammatory response triggered in the early post-MI phase involving cardiomyocytes, (myo)fibroblasts, endothelial cells, and infiltrating immune cells. Next, we explore how the bone marrow and extramedullary hematopoiesis (such as in the spleen) contribute to sustaining immune cell supply at a cardiac level. Lastly, we discuss recent findings on how metabolic cardiovascular risk factors, including hypercholesterolemia, hypertriglyceridemia, diabetes, and hypertension, disrupt this immunological response and explore the potential modulatory effects of lifestyle habits and pharmacological interventions. Understanding how different metabolic risk factors influence the inflammatory response triggered by MI and unraveling the underlying molecular and cellular mechanisms may pave the way for developing personalized therapeutic approaches based on the patient's metabolic profile. Similarly, delving deeper into the impact of lifestyle modifications on the inflammatory response post-MI is crucial. These insights may enable the adoption of more effective strategies to manage post-MI inflammation and improve cardiovascular health outcomes in a holistic manner.

PCSK9 inhibitor in acute ischemic stroke patient receiving mechanical thrombectomy: early outcomes and safety

Background

Lipid-lowering therapies are mainstays in reducing recurrence after acute ischemic stroke (AIS). Evolocumab, a Proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitor, is a promising lipid-lowering agent known to decrease LDL cholesterol and mitigate vascular events alongside statins. However, its effects on the early functional outcomes post-mechanical thrombectomy (MT) remain unclear. This study aimed to assess the short-term effects and incidence of bleeding events after the early, off-label use of PCSK9 inhibitors in AIS patients undergoing MT.

Methods

We retrospectively analyzed patients who had MT at a Regional Stroke Center from December 2018 to April 2023. Our primary outcome was discharge functional outcomes. Secondary outcomes included early neurologic deterioration (END), symptomatic intracerebral hemorrhage (sICH), 3-month functional outcomes, 3-month recurrence rate, and lipid profiles.

Results

Of 261 patients (mean age 69.2 ± 11.7, men 42.9%), 42 were administered evolocumab peri-procedurally. While baseline characteristics were similar between the two groups, evolocumab group demonstrated improved discharge outcomes, with a lower mean NIHSS (8.8 ± 6.8 vs. 12.4 ± 9.8, p = 0.02) and a higher percentage of patients with discharge mRS ≤ 3 (52.4% vs. 35.6%, p = 0.041). The 3-month follow-up show a non-significant trend toward an improved outcome in the evolocumab group. Multivariable analysis indicated that evolocumab had a potential impact on favorable discharge outcomes (aOR 1.98[0.94-4.22] for mRS ≤ 3 and 0.47[0.27-0.84] for lower ordinal mRS). Notably, evolocuamb users exhibited fewer instances of END and sICH, although they do not reach statistical significance. Additionally, the evolocumab group demonstrated potential benefits in LDL cholesterol reduction over time.

Conclusion

Early use of evolocumab in AIS patients undergoing MT appeared to be safe and associated with better early functional outcomes. The potential benefit of the PCSK9 inhibitor shown here warrants further prospective studies.

Inhibition of PCSK9 with evolocumab modulates lipoproteins and monocyte activation in high-risk ASCVD subjects

BACKGROUND

Mechanistic studies suggest that proprotein convertase subtilisin/kexin type 9 inhibitors can modulate inflammation.

METHODS

Double-blind, placebo-controlled trial randomized 41 ASCVD subjects with type 2 diabetes with microalbuminuria and LDL-C level >70 mg/dL on maximum tolerated statin therapy received subcutaneous evolocumab 420 mg every 4 weeks or matching placebo. The primary outcomes were change in circulating immune cell transcriptional response, lipoproteins and blood viscosity at 2 weeks and 12 weeks. Safety was assessed in all subjects who received at least one dose of assigned treatment and analyses were conducted in the intention-to-treat population.

RESULTS

All 41 randomized subjects completed the 2-week visit. Six subjects did not receive study medication consistently after the 2-week visit due to COVID-19 pandemic suspension of research activities. The groups were well-matched with respect to age, comorbidities, baseline LDL-C, white blood cell counts, and markers of systemic inflammation. Evolocumab reduced LDL-C by -68.8% (p < 0.0001) and -52.8% (p < 0.0001) at 2 and 12 weeks, respectively. There were no differences in blood viscosity at baseline nor at 2 and 12 weeks. RNA-seq was performed on peripheral blood mononuclear cells with and without TLR4 stimulation ("Stress" transcriptomics). "Stress" transcriptomics unmasked immune cell phenotypic differences between evolocumab and placebo groups at 2 and 12 weeks.

CONCLUSIONS

This trial is the first to demonstrate that PCSK9 mAB with evolocumab can modulate circulating immune cell properties and highlights the importance of "stress" profiling of circulating immune cells that more clearly define immune contributions to ASCVD.

PCSK9 plasma concentration is associated with epicardial adipose tissue volume and metabolic control in patients with type 1 diabetes

Patients with type 1 diabetes (T1D) have a greater risk of cardiovascular disease. Proconvertase subtilisin-kexin 9 (PCSK9) is involved in the atherosclerosis process. This study aimed to determine the relationship between PCSK9 levels and epicardial adipose tissue (EAT) volume and cardiometabolic variables in patients with T1D. This was an observational cross-sectional study including 73 patients with T1D. Clinical, biochemical and imaging data were collected. We divided the patients into two groups according to their glycemic control and the EAT index (iEAT) percentile. We performed a correlation analysis between the collected variables and PCSK9 levels; subsequently, we performed a multiple regression analysis with the significant parameters. The mean age was 47.6 ± 8.5 years, 58.9% were men, and the BMI was 26.9 ± 4.6 kg/m2. A total of 31.5%, 49.3% and 34.2% of patients had hypertension, dyslipidemia and smoking habit, respectively. The PCSK9 concentration was 0.37 ± 0.12 mg/L, which was greater in patients with worse glycemic control (HbA1c > 7.5%), dyslipidemia and high EAT volume (iEAT > 75th percentile). The PCSK9 concentration was positively correlated with age (r = 0.259; p = 0.027), HbA1c (r = 0.300; p = 0.011), insulin dose (r = 0.275; p = 0.020), VLDL-C level (r = 0.331; p = 0.004), TG level (r = 0.328; p = 0.005), and iEAT (r = 0.438; p < 0.001). Multiple regression analysis revealed that 25% of the PCSK9 variability was explained by iEAT and HbA1c (p < 0.05). The PCSK9 concentration is associated with metabolic syndrome parameters, poor glycemic control and increased EAT volume in patients with T1D.

A Non-Coronary, Peripheral Arterial Atherosclerotic Disease (Carotid, Renal, Lower Limb) in Elderly Patients-A Review: Part I-Epidemiology, Risk Factors, and Atherosclerosis-Related Diversities in Elderly Patients

Atherosclerosis is a generalized and progressive disease. Ageing is a key risk factor for atherosclerosis progression that is associated with the increased incidence of ischemic events in supplied organs, including stroke, coronary events, limb ischemia, or renal failure. Cardiovascular disease is the leading cause of death and major disability in adults ≥ 75 years of age. Atherosclerotic occlusive disease affects everyday activity and quality of life, and it is associated with reduced life expectancy. Although there is evidence on coronary artery disease management in the elderly, there is insufficient data on the management in older patients presented with atherosclerotic lesions outside the coronary territory. Despite this, trials and observational studies systematically exclude older patients, particularly those with severe comorbidities, physical or cognitive dysfunctions, frailty, or residence in a nursing home. This results in serious critical gaps in knowledge and a lack of guidance on the appropriate medical treatment and referral for endovascular or surgical interventions. Therefore, we attempted to gather data on the prevalence, risk factors, and management strategies in patients with extra-coronary atherosclerotic lesions.

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.

Opposite causal effects of birthweight on myocardial infarction and atrial fibrillation and the distinct mediating pathways: a Mendelian randomization study

BACKGROUND

Previous observational studies have documented an inverse association of birthweight with myocardial infarction (MI) but a positive association with atrial fibrillation (AF). However, the causality of these associations and the underlying mediating pathways remain unclear. We aimed to investigate the causal effects of birthweight, incorporating both fetal and maternal genetic effects, on MI and AF, and identify potential mediators in their respective pathways.

METHODS

We performed Mendelian randomization (MR) analyses using genome-wide association study summary statistics for birthweight (N = 297,356 for own birthweight and 210,248 for offspring birthweight), MI (Ncase=61,000, Ncontrol=577,000), AF (Ncase=60,620, Ncontrol=970,216), and 52 candidate mediators (N = 13,848-1,295,946). Two-step MR was employed to identify and assess the mediation proportion of potential mediators in the associations of birthweight with MI and AF, respectively. As a complement, we replicated analyses for fetal-specific birthweight and maternal-specific birthweight.

RESULTS

Genetically determined each 1-SD lower birthweight was associated with a 40% (95% CI: 1.22-1.60) higher risk of MI, whereas each 1-SD higher birthweight was causally associated with a 29% (95% CI: 1.16-1.44) higher risk of AF. Cardiometabolic factors, including lipids and lipoproteins, glucose and insulin, blood pressure, and fatty acids, each mediated 4.09-23.71% of the total effect of birthweight on MI, followed by body composition and strength traits (i.e., appendicular lean mass, height, and grip strength) and socioeconomic indicators (i.e., education and household income), with the mediation proportion for each factor ranging from 8.08 to 16.80%. By contrast, appendicular lean mass, height, waist circumference, childhood obesity, and body mass index each mediated 15.03-45.12% of the total effect of birthweight on AF. Both fetal-specific birthweight and maternal-specific birthweight were inversely associated with MI, while only fetal-specific birthweight was positively associated with AF. Psychological well-being and lifestyle factors conferred no mediating effect in either association.

CONCLUSIONS

Cardiometabolic factors mainly mediated the association between lower birthweight and MI, while body composition and strength traits mediated the association between higher birthweight and AF. These findings provide novel evidence for the distinct pathogenesis of MI and AF and advocate adopting a life-course approach to improving fetal development and subsequent causal mediators to mitigate the prevalence and burden of cardiovascular diseases.

PCSK9 activation promotes early atherosclerosis in a vascular microphysiological system

Atherosclerosis is a primary precursor of cardiovascular disease (CVD), the leading cause of death worldwide. While proprotein convertase subtilisin/kexin 9 (PCSK9) contributes to CVD by degrading low-density lipoprotein receptors (LDLR) and altering lipid metabolism, PCSK9 also influences vascular inflammation, further promoting atherosclerosis. Here, we utilized a vascular microphysiological system to test the effect of PCSK9 activation or repression on the initiation of atherosclerosis and to screen the efficacy of a small molecule PCSK9 inhibitor. We have generated PCSK9 over-expressed (P+) or repressed (P-) human induced pluripotent stem cells (iPSCs) and further differentiated them to smooth muscle cells (viSMCs) or endothelial cells (viECs). Tissue-engineered blood vessels (TEBVs) made from P+ viSMCs and viECs resulted in increased monocyte adhesion compared to the wild type (WT) or P- equivalents when treated with enzyme-modified LDL (eLDL) and TNF-α. We also found significant viEC dysfunction, such as increased secretion of VCAM-1, TNF-α, and IL-6, in P+ viECs treated with eLDL and TNF-α. A small molecule compound, NYX-1492, that was originally designed to block PCSK9 binding with the LDLR was tested in TEBVs to determine its effect on lowering PCSK9-induced inflammation. The compound reduced monocyte adhesion in P+ TEBVs with evidence of lowering secretion of VCAM-1 and TNF-α. These results suggest that PCSK9 inhibition may decrease vascular inflammation in addition to lowering plasma LDL levels, enhancing its anti-atherosclerotic effects, particularly in patients with elevated chronic inflammation.

Inflammasomes in Atherosclerosis-From Pathophysiology to Treatment

Atherosclerosis, a chronic inflammatory disease characterized by arterial plaque accumulation, remains a significant global health challenge. In recent years, inflammasomes, the intracellular multiprotein complexes crucial for initiating innate immune responses, have emerged as key players in atherosclerosis pathophysiology. This review article aims to provide a comprehensive overview of the current understanding of inflammasome activation and its impact on atherosclerosis development and progression. We explore the intricate interplay between traditional cardiovascular risk factors and inflammasome activation, leading to the perpetuation of inflammatory cascades that drive plaque formation and instability. The review focuses on the molecular mechanisms underlying inflammasome activation, including the role of pattern recognition receptors and cytokines in this process. Moreover, we discuss the contribution of inflammasomes to endothelial dysfunction, foam cell formation, and vascular inflammation. Additionally, recent advances in therapeutic strategies targeting inflammasomes are examined, including pharmacological agents and potential immunomodulatory approaches. By collating and analyzing the current evidence, this review provides valuable insights into the potential of inflammasome-targeted therapies for atherosclerosis management and treatment. Understanding the pivotal role of inflammasomes in atherosclerosis pathophysiology offers promising prospects for developing effective and personalized therapeutic interventions that can mitigate the burden of this prevalent cardiovascular disorder and improve patient outcomes.

What are the benefits and drawbacks of statins in carotid artery disease? A perspective review

INTRODUCTION

The prevalence of carotid artery stenosis in the general population is approximately 3%, but approximately 20% among people with acute ischemic stroke. Statins are recommended by multiple international guidelines as the drug of choice for lipid control in people with asymptomatic or symptomatic carotid artery stenosis due to their lipid-lowering and other pleiotropic effects.

AREAS COVERED

This review discusses the guidelines for statin usage as a cornerstone in the prevention and management of atherosclerotic carotid artery disease and the impact of statins on stroke incidence and mortality. Statin side effects, alternative therapy, and genetic polymorphisms are reviewed.

EXPERT OPINION

Statin therapy is associated with a decreased incidence of stroke and mortality as well as improved outcomes for patients treated with carotid revascularization. Statins are a safe and effective class of medications, but the initiation of therapy warrants close monitoring to avoid rare and potentially serious side effects. Lack of clinical efficacy or the presence of side effects suggests a need for treatment with an alternative therapy such as PCSK9 inhibitors. Understanding the interplay between the mechanisms of statins and PCSK9 inhibition therapies will allow optimal benefits while minimizing risks. Future research into genetic polymorphisms may improve patient selection for personalized therapy.