Effect of Evolocumab on Coronary Plaque Composition

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.

Role of Lipid-Lowering and Anti-Inflammatory Therapies on Plaque Stabilization

Atherosclerosis is the predominant underlying etiopathology of coronary artery disease. Changes in plaque phenotype from stable to high risk may spur future major adverse cardiac events (MACE). Different pharmacological therapies have been implemented to mitigate this risk. Over the last two decades, intravascular imaging modalities have emerged in clinical studies to clarify how these therapies may affect the composition and burden of coronary plaques. Lipid-lowering agents, such as statins, ezetimibe, and proprotein convertase subtilisin/kexin type 9 inhibitors, were shown not only to reduce low-density lipoprotein levels and MACE but also to directly affect features of coronary plaque vulnerability. Studies have demonstrated that lipid-lowering therapy reduces the percentage of atheroma volume and number of macrophages and increases fibrous cap thickness. Future studies should answer the question of whether pharmacological plaque stabilization may be sufficient to mitigate the risk of MACE for selected groups of patients with atherosclerotic coronary disease.

Serial longitudinal changes of coronary calcified plaques with clear outer borders under intensive lipid management: insights from optical coherence tomography

Percutaneous coronary intervention (PCI) for calcified lesions is one of the most challenging procedures related to worse clinical outcomes. To stabilize vulnerable plaques, intensive lipid management is recommended; however, the serial changes of calcified plaques under intensive lipid management are unknown. A total of 31 patients (mean age, 63 ± 10 years; men, 29 patients) who underwent PCI with intensive lipid management were retrospectively studied. We evaluated the serial longitudinal changes of calcified plaques with clear outer borders using optical coherence tomography (OCT) at two time points: at the time of PCI (baseline) and the chronic phase. The median interval from PCI to chronic phase was 287 (233-429) days. Twenty-eight patients (90.3%) had increased calcium volume at the chronic phase compared with those at baseline (2.6 [1.3-5.1] vs. 1.8 [0.7-4.3] mm2, p < 0.05), and the median increase rate of calcium volume was 27.4% at the chronic phase. According to the median increase rate of calcium volume (27.4%), patients were divided into the following two groups: rapid progression (≥ 27.4%, RP group) and non-rapid progression (< 27.4%, non-RP group). The RP group had more patients with diabetes, and diabetes was independently associated with rapid progression by multivariate analysis. Furthermore, patients with diabetes had significantly higher changes in calcium index and volume from the baseline to the chronic phase than those without diabetes. Coronary calcification progression during relatively short intervals was observed using OCT even under intensive lipid management. Diabetes was an independent predictor for rapid coronary calcification progression.

Management of dyslipidemia in coronary artery disease: the present and the future

Coronary artery disease (CAD) remains a leading cause of global morbidity and mortality, necessitating continuous refinement in the management of dyslipidemia, one of its major risk factors, to mitigate cardiovascular risks. Previous studies have proven the critical role of immediate and robust low-density lipoprotein cholesterol (LDL-C) reduction in the aftermath of acute coronary syndrome (ACS). Emphasizing the evidence supporting this approach, we delve into the impact of early intervention on cardiovascular outcomes and propose optimal strategies for achieving rapid LDL-C lowering, while also providing the rationale for early proprotein convertase subtilisin/kexin 9 inhibitor use after an ACS. Given the importance of the residual lipidemic risk, we present an overview of emerging therapeutic avenues poised to reshape dyslipidemia management, such as bempedoic acid, lipoprotein(a) inhibition, ApoC3 modulation, and angiopoietin-like protein 3 targeting. This comprehensive review amalgamates current evidence with future prospects, offering a holistic perspective on the management of dyslipidemia in CAD. By exploring both the urgency for immediate post-ACS LDL-C reduction and the exciting advancements on the horizon, this article provides a roadmap for clinicians navigating the intricate landscape of lipid-lowering therapies in CAD.

Invasive coronary imaging of inflammation to further characterize high-risk lesions: what options do we have?

Coronary atherosclerosis remains a leading cause of morbidity and mortality worldwide. The underlying pathophysiology includes a complex interplay of endothelial dysfunction, lipid accumulation and inflammatory pathways. Multiple structural and inflammatory features of the atherosclerotic lesions have become targets to identify high-risk lesions. Various intracoronary imaging devices have been developed to assess the morphological, biocompositional and molecular profile of the intracoronary atheromata. These techniques guide interventional and therapeutical management and allow the identification and stratification of atherosclerotic lesions. We sought to provide an overview of the inflammatory pathobiology of atherosclerosis, distinct high-risk plaque features and the ability to visualize this process with contemporary intracoronary imaging techniques.

Targeting proprotein convertase subtilisin/kexin type 9 (PCSK9): from bench to bedside

Proprotein convertase subtilisin/kexin type 9 (PCSK9) has evolved as a pivotal enzyme in lipid metabolism and a revolutionary therapeutic target for hypercholesterolemia and its related cardiovascular diseases (CVD). This comprehensive review delineates the intricate roles and wide-ranging implications of PCSK9, extending beyond CVD to emphasize its significance in diverse physiological and pathological states, including liver diseases, infectious diseases, autoimmune disorders, and notably, cancer. Our exploration offers insights into the interaction between PCSK9 and low-density lipoprotein receptors (LDLRs), elucidating its substantial impact on cholesterol homeostasis and cardiovascular health. It also details the evolution of PCSK9-targeted therapies, translating foundational bench discoveries into bedside applications for optimized patient care. The advent and clinical approval of innovative PCSK9 inhibitory therapies (PCSK9-iTs), including three monoclonal antibodies (Evolocumab, Alirocumab, and Tafolecimab) and one small interfering RNA (siRNA, Inclisiran), have marked a significant breakthrough in cardiovascular medicine. These therapies have demonstrated unparalleled efficacy in mitigating hypercholesterolemia, reducing cardiovascular risks, and have showcased profound value in clinical applications, offering novel therapeutic avenues and a promising future in personalized medicine for cardiovascular disorders. Furthermore, emerging research, inclusive of our findings, unveils PCSK9's potential role as a pivotal indicator for cancer prognosis and its prospective application as a transformative target for cancer treatment. This review also highlights PCSK9's aberrant expression in various cancer forms, its association with cancer prognosis, and its crucial roles in carcinogenesis and cancer immunity. In conclusion, this synthesized review integrates existing knowledge and novel insights on PCSK9, providing a holistic perspective on its transformative impact in reshaping therapeutic paradigms across various disorders. It emphasizes the clinical value and effect of PCSK9-iT, underscoring its potential in advancing the landscape of biomedical research and its capabilities in heralding new eras in personalized medicine.

Bibliometric analysis of monoclonal antibodies for atherosclerosis

Atherosclerosis (AS) is a prevalent cardiovascular disease that greatly increases mortality in the aging population and imposes a heavy burden on global healthcare systems. The purpose of this study is to examine the research structure and current trends of monoclonal antibodies (mAbs) against AS from a bibliometric perspective, since the development of these drugs is currently booming. This study collected articles and reviews on mAbs against AS from the Web of Science Core Collection, spanning from 2003 to 2022. Biblioshiny was utilized to analyze and visualize the characteristics of countries, regions, authors, institutions, and journals included in this collection. We used VOS viewer to illustrate the frequency of country co-occurrence, and CiteSpace to visualize co-cited reference, keywords co-occurrence, keywords citation bursts, keywords clustering and timeline plots. The study included 1325 publications, with the United States emerging as a leading contributor to the field. ATHEROSCLEROSIS, CIRCULATION and ARTERIOSCLEROSISTHROMBOSIS AND VASCULAR BIOLOGY are core journals that publish high-quality literature on the latest advances in the field. Noteworthy authors with numerous high-quality publications include Witztum JL and Tsimikas S. Currently, lipid metabolism and inflammation are the main research areas of interest in this field. The mAbs against AS is an evolving field, and ongoing research continues to advance our understanding. This paper provides a comprehensive overview of the current state of knowledge in this area, highlighting two primary research directions: inflammation and lipid metabolism. Additionally, the paper identifies emerging research hotspots, which will provide researchers with useful insights to guide future investigations and anticipate research directions.

Effect of PCSK9 antibodies on coronary plaque regression and stabilization derived from intravascular imaging in patients with coronary artery disease: A meta-analysis

BACKGROUND

Despite extensive evidence demonstrating the beneficial effects of the additional PCSK9 antibodies with high-density statins treatment on cardiovascular clinical outcomes, the potent causes underlying these effects remain elusive. This meta-analysis aimed at exploring the underlying causes to assess the effect of PCSK9 antibodies on the regression and stabilization of coronary plaque derived from intravascular imaging in statin-treated patients with coronary artery disease (CAD).

METHODS

PubMed, Embase, and Cochrane Library were searched from inception to February 1, 2023, for randomized controlled trials (RCTs), nonrandomized studies without language restrictions if they described the association between PCSK9 antibodies with coronary plaque regression and stabilization evaluated by intravascular imaging in statin-treated patients with CAD. Meta-analyses were performed for mean difference (MD) and odds ratio (OR) using a random-effects model. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.

RESULTS

A total of 9 studies (7 RCTs and 2 non-RCTs) with 2290 CAD patients were identified and included. Among statin-treated CAD patients, the addition use of PCSK9 antibodies was associated with IVUS-derived percent atheroma volume (PAV) (4 studies with 1875 participants; MD, -1.26; 95% CI, -1.51 to -1.00; P < 0.01), total atheroma volume (TAV) (4 studies with 1875 participants; MD, -7.23; 95% CI, -11.28 to -3.18; P < 0.01), incidence of PAV regression (4 studies with 1875 participants; OR, 2.24; 95% CI, 1.81 to 2.77; P < 0.01) and incidence of TAV regression (3 studies with 1256 participants; OR, 1.66; 95% CI, 1.33 to 2.09; P < 0.01) in Caucasians instead of Asians from multiple countries; OCT-derived minimum fibrous cap thickness (FCT) (6 studies with 841 participants; MD, 25.16; 95% CI, 14.06 to 36.27; P < 0.01), incidence of thin-capped fibroatheroma (TCFA) regression (2 studies with 222 participants; OR, 2.56; 95% CI, 1.42 to 4.61; P < 0.01) and maximum lipid arc (4 studies with 280 participants; MD, -14.96; 95% CI, -22.10 to -7.83; P < 0.01) in Asians and Caucasians without races restrictions.

CONCLUSIONS

PCSK9 antibodies resulted in significantly greater coronary plaque regression and stabilization in statin-treated CAD patients, mostly Caucasians from multiple countries. Further studies are needed to assess the effect for Asian patients.

Impact of PCSK9 inhibitors on coronary atheroma phenotype following myocardial infarction: insights from intravascular imaging

PURPOSE OF REVIEW

The aim of this study was to review the impact of combination lipid lowering with statins and proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors on coronary atherosclerosis using serial intravascular imaging.

RECENT FINDINGS

Early studies using intravascular ultrasound established the ability of increasingly intensive lipid lowering to both slow progression and ultimately promote regression of coronary disease. More recent clinical trials that have employed serial imaging with optical coherence tomography have permitted the ability to evaluate the impact of intensive lipid lowering on compositional features associated with plaque vulnerability. In particular, the combination of intensive statin and PCSK9 inhibitor therapy promotes plaque stability in patients following an acute coronary syndrome.

SUMMARY

More intensive lipid lowering using the combination of statins and PCSK9 inhibitors promote plaque regression in addition to promoting calcification, fibrous cap thickening and reductions in plaque lipid. These plaque-stabilizing effects underscore the benefits of combination therapy on cardiovascular events and highlight the importance of combination lipid-lowering therapy.

Aggressive LDL-C Lowering and the Brain: Impact on Risk for Dementia and Hemorrhagic Stroke: A Scientific Statement From the American Heart Association

The objective of this scientific statement is to evaluate contemporary evidence that either supports or refutes the conclusion that aggressive low-density lipoprotein cholesterol lowering or lipid lowering exerts toxic effects on the brain, leading to cognitive impairment or dementia or hemorrhagic stroke. The writing group used literature reviews, references to published clinical and epidemiology studies, clinical and public health guidelines, authoritative statements, and expert opinion to summarize existing evidence and to identify gaps in current knowledge. Although some retrospective, case control, and prospective longitudinal studies suggest that statins and low-density lipoprotein cholesterol lowering are associated with cognitive impairment or dementia, the preponderance of observational studies and data from randomized trials do not support this conclusion. The risk of a hemorrhagic stroke associated with statin therapy in patients without a history of cerebrovascular disease is nonsignificant, and achieving very low levels of low-density lipoprotein cholesterol does not increase that risk. Data reflecting the risk of hemorrhagic stroke with lipid-lowering treatment among patients with a history of hemorrhagic stroke are not robust and require additional focused study.

The Inhibition of Evolocumab on Non-Infarct-Related Artery Disease in Patients with ST-Elevation Myocardial Infarction

Purpose

The effects of combing evolocumab and statin on the clinical outcome and physiological function of coronary arteries in STEMI patients with non-infarct-related artery (NIRA) disease are still unclear.

Methods

A total of 355 STEMI patients with NIRA were enrolled in this study, who underwent combined quantitative flow ratio (QFR) at baseline and after 12 months of treatment with statin monotherapy or statin plus evolocumab.

Results

Diameter stenosis and lesion length were significantly lower in the group undergoing statin plus evolocumab. While the group exhibited significantly higher minimum lumen diameter (MLD), and QFR values. Statin plus evolocumab (OR = 0.350; 95% CI: 0.149-0.824; P = 0.016) and plaque lesion length (OR = 1.223; 95% CI: 1.102-1.457; P = 0.033) were independently associated with rehospitalization for unstable angina (UA) within 12 months.

Conclusion

Evolocumab combined with statin therapy can significantly improve the anatomical and physiological function of the coronary arteries and downregulate the re-hospitalization rate due to UA in STEMI patients with NIRA.

Novel ultrasound techniques in the identification of vulnerable plaques-an updated review of the literature

Atherosclerosis is an inflammatory disease partly mediated by lipoproteins. The rupture of vulnerable atherosclerotic plaques and thrombosis are major contributors to the development of acute cardiovascular events. Despite various advances in the treatment of atherosclerosis, there has been no satisfaction in the prevention and assessment of atherosclerotic vascular disease. The identification and classification of vulnerable plaques at an early stage as well as research of new treatments remain a challenge and the ultimate goal in the management of atherosclerosis and cardiovascular disease. The specific morphological features of vulnerable plaques, including intraplaque hemorrhage, large lipid necrotic cores, thin fibrous caps, inflammation, and neovascularisation, make it possible to identify and characterize plaques with a variety of invasive and non-invasive imaging techniques. Notably, the development of novel ultrasound techniques has introduced the traditional assessment of plaque echogenicity and luminal stenosis to a deeper assessment of plaque composition and the molecular field. This review will discuss the advantages and limitations of five currently available ultrasound imaging modalities for assessing plaque vulnerability, based on the biological characteristics of the vulnerable plaque, and their value in terms of clinical diagnosis, prognosis, and treatment efficacy assessment.

Evolocumab attenuate pericoronary adipose tissue density via reduction of lipoprotein(a) in type 2 diabetes mellitus: a serial follow-up CCTA study

BACKGROUND

Pericoronary adipose tissue (PCAT) density is a biomarker of vessel inflammation, which is supposed to be increased in patients with type 2 diabetes mellitus (T2DM). However, whether the coronary inflammation revealed by this novel index could be alleviated after evolocumab treatment in T2DM remains unknown.

METHODS

From January 2020 to December 2022, consecutive T2DM patients with low-density lipoprotein cholesterol ≥ 70 mg/dL on maximally tolerated statin and taking evolocumab were prospectively included. In addition, patients with T2DM who were taking statin alone were recruited as control group. The eligible patients underwent baseline and follow-up coronary CT angiography with an interval of 48-week. To render patients with evolocumab as comparable to those controls, a propensity-score matching design was used to select the matched pairs with a 1:1 ratio. Obstructive lesion was defined as the extent of coronary artery stenosis ≥ 50%; the numbers inside the brackets were interquartile ranges.

RESULTS

A total of 170 T2DM patients with stable chest pain were included [(mean age 64 ± 10.6 [range 40-85] years; 131 men). Among those patients, 85 were in evolocumab group and 85 were in control group. During follow-up, low-density lipoprotein cholesterol (LDL-C) level (2.02 [1.26, 2.78] vs. 3.34 [2.53, 4.14], p < 0.001), and lipoprotein(a) (12.1 [5.6, 21.8] vs. 18.9 [13.2, 27.2], p = 0.002) were reduced after evolocumab treatment. The prevalence of obstructive lesions and high-risk plaque features were significantly decreased (p < 0.05 for all). Furthermore, the calcified plaque volume were significantly increased (188.3 [115.7, 361.0] vs. 129.3 [59.5, 238.3], p = 0.015), while the noncalcified plaque volume and necrotic volume were diminished (107.5 [40.6, 180.6] vs. 125.0 [65.3, 269.7], p = 0.038; 0 [0, 4.7] vs. 0 [0, 13.4], p < 0.001, respectively). In addition, PCAT density of right coronary artery was significantly attenuated in evolocumab group (- 85.0 [- 89.0, - 82.0] vs. - 79.0 [- 83.5, - 74.0], p < 0.001). The change in the calcified plaque volume inversely correlated with achieved LDL-C level (r =  - 0.31, p < 0.001) and lipoprotein(a) level (r =  - 0.33, p < 0.001). Both the changes of noncalcified plaque volume and necrotic volume were positively correlated with achieved LDL-C level and Lp(a) (p < 0.001 for all). However, the change of PCAT_RCA density only positively correlated with achieved lipoprotein(a) level (r = 0.51, p < 0.001). Causal mediation analysis revealed Lp(a) level mediated 69.8% (p < 0.001) for the relationship between evolocumab and changes of PCAT_RCA.

CONCLUSIONS

In patients with T2DM, evolocumab is an effective therapy to decrease noncalcified plaque volume necrotic volume, and increase calcified plaque volume. Furthermore, evolocumab could attenuate PCAT density, at least in part, via the reduction of lipoprotein(a).

Feasibility of Short-Term Aggressive Lipid-Lowering Therapy with the PCSK9 Antibody in Acute Coronary Syndrome

BACKGROUND

The guideline-recommended low-density lipoprotein cholesterol target level of <70 mg/dL may not be achieved with statin administration in some patients with acute coronary syndrome (ACS). Therefore, the proprotein convertase subtilisin-kexin type 9 (PCSK9) antibody can be added to high-risk patients with ACS. Nevertheless, the optimal duration of PCSK9 antibody administration remains unclear.

METHODS AND RESULTS

Patients were randomized to receive either 3 months of lipid lowering therapy (LLT) with the PCSK9 antibody followed by conventional LLT (with-PCSK9-antibody group) or 12 months of conventional LLT alone (without-PCSK9-antibody group). The primary endpoint was the composite of all-cause death, myocardial infarction, stroke, unstable angina, and ischemia-driven revascularization. A total of 124 patients treated with percutaneous coronary intervention (PCI) were randomly assigned to the two groups (n = 62 in each). The primary composite outcome occurred in 9.7% and 14.5% of the patients in the with- and without-PCSK9-antibody groups, respectively (hazard ratio: 0.70; 95% confidence interval: 0.25 to 1.97; p = 0.498). The two groups showed no significant differences in hospitalization for worsening heart failure and adverse events.

CONCLUSIONS

In ACS patients who underwent PCI, short-term PCSK9 antibody therapy with conventional LLT was feasible in this pilot clinical trial. Long-term follow-up in a larger scale clinical trial is warranted.

Alirocumab and Coronary Atherosclerosis in Asymptomatic Patients with Familial Hypercholesterolemia: The ARCHITECT Study

BACKGROUND

The effect of alirocumab, a PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitor, on coronary plaque burden in patients with familial hypercholesterolemia has not been addressed. Our aim was to assess changes in coronary plaque burden and its characteristics after treatment with alirocumab by quantification and characterization of atherosclerotic plaque throughout the coronary tree on the basis of a noninvasive analysis of coronary computed tomographic angiography in asymptomatic subjects with familial hypercholesterolemia receiving optimized and stable treatment with maximum tolerated statin dose with or without ezetimibe.

METHODS

This study is a phase IV, open-label, multicenter, single-arm clinical trial to assess changes in coronary plaque burden and its characteristics after 78 weeks of treatment with alirocumab in patients with familial hypercholesterolemia without clinical atherosclerotic cardiovascular disease. Participants underwent an initial coronary computed tomographic angiography at baseline and another at 78 weeks. Every patient received 150 mg of alirocumab subcutaneiously every 14 days in addition to high-intensity statin therapy. The main outcome was the change on coronary plaque burden and its characteristics by quantification and characterization of atherosclerotic plaque throughout the coronary tree on the basis of analysis of coronary computed tomographic angiography.

RESULTS

The study was completed by 104 patients. The median age was 53.3 (46.2-59.4) years. Of these patients, 54 were women (51.9%). Median low-density lipoprotein cholesterol was 138.9 (117.5-175.3) mg/dL at entry and 45.0 (36.0-65.0) mg/dL at follow-up (P<0.001). Coronary plaque burden changed from 34.6% (32.5%-36.8%) at entry to 30.4% (27.4%-33.4%) at follow-up (P<0.001). A significant change in the characteristics of the coronary atherosclerosis was also found: an increase in the proportion of calcified (+0.3%; P<0.001) and mainly fibrous (+6.2%; P<0.001) plaque, accompanied by a decrease in the percentage of fibro-fatty (-3.9%; P<0.001) and necrotic plaque (-0.6%; P<0.001).

CONCLUSIONS

Treatment with alirocumab in addition to high-intensity statin therapy resulted in significant regression of coronary plaque burden and plaque stabilization on coronary computed tomographic angiography over 78 weeks in these groups of patients with familial hypercholesterolemia without clinical atherosclerotic cardiovascular disease. ARCHITECT (Effect of Alirocumab on Atherosclerotic Plaque Volume, Architecture and Composition) could link and explain ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) results.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT05465278.

Stabilization of vulnerable plaque in the ACS patient: evidence from HUYGENS studies

The introduction of PCSK9 inhibitors in addition to statin therapy allowed better control of LDL-C plasma levels with a subsequent reduction of cardiovascular events. Human atherosclerosis has been previously considered an irreversible condition; studies firstly based on angiography imaging and secondly with intra-coronary imaging-mainly IVUS based-have demonstrated that lipid-lowering therapy based on statins can stabilize and even reduce atherosclerotic burden of coronary circulation. While plaque stabilization and/or reduction with PCSK9 inhibitors have already been demonstrated in the GLAGOV study, the HUYGENS study showed a positive effect not only on atherosclerotic burden but also on plaque phenotype, with an increased FCT, decrease in maximum lipid arch, and reduction of macrophages infiltration. Further studies need to assess the clinical impact of the reduction of plaques displaying high-risk features with PCSK9 inhibitors.

Intravascular Ultrasound in Vulnerable Plaque and Acute Coronary Syndrome

Vulnerable plaque plays a pivotal role in the pathogenesis of acute coronary syndrome (ACS), being responsible for most ACS. The concept of vulnerable plaque has evolved with advancements in basic and clinical investigations along with developments and rapid expansion of coronary imaging modalities. Intravascular ultrasound (IVUS) is the first widely applied clinical technology with sufficient tissue penetration and enables us to identify vulnerable plaque and comprehensively understand the pathophysiology of ACS. In this review, we summarize current clinical evidence established by IVUS and the recent advancements in our understanding of vulnerable plaque and its role in ACS management.

Intravascular imaging assessment of pharmacotherapies targeting atherosclerosis: advantages and limitations in predicting their prognostic implications

Intravascular imaging has been often used over the recent years to examine the efficacy of emerging therapies targeting plaque evolution. Serial intravascular ultrasound, optical coherence tomography, or near-infrared spectroscopy-intravascular ultrasound studies have allowed us to evaluate the effects of different therapies on plaque burden and morphology, providing unique mechanistic insights about the mode of action of these treatments. Plaque burden reduction, a decrease in necrotic core component or macrophage accumulation-which has been associated with inflammation-and an increase in fibrous cap thickness over fibroatheromas have been used as surrogate endpoints to assess the value of several drugs in inhibiting plaque evolution and improving clinical outcomes. However, some reports have demonstrated weak associations between the effects of novel treatments on coronary atheroma and composition and their prognostic implications. This review examines the value of invasive imaging in assessing pharmacotherapies targeting atherosclerosis. It summarizes the findings of serial intravascular imaging studies assessing the effects of different drugs on atheroma burden and morphology and compares them with the results of large-scale trials evaluating their impact on clinical outcome. Furthermore, it highlights the limited efficacy of established intravascular imaging surrogate endpoints in predicting the prognostic value of these pharmacotherapies and introduces alternative imaging endpoints based on multimodality/hybrid intravascular imaging that may enable more accurate assessment of the athero-protective and prognostic effects of emerging therapies.

Safety and Effectiveness of Evolocumab During Acute and Sub-acute Phases of Acute Coronary Syndrome (ACS): A Systematic Review and Meta-analysis

BACKGROUND

Coronary artery disease (CAD), manifested mainly as acute coronary syndrome (ACS), continues to be a major cause of mortality globally and a significant contributing factor to the global disease burden. Elevation of low-density lipoprotein cholesterol levels attributed to proprotein convertase subtilisin/Kexin type-9 (PCSK9) during and following ACS puts patients at high risk of subsequent adverse events. Evolocumab is a PCSK9 inhibitor that is associated with a significant reduction in low-density lipoprotein cholesterol (LDL-C) levels through PCSK9 inhibition in comparison to traditional statin therapy.

METHODS

We conducted a systematic review and meta-analysis of literature addressing the efficacy and safety of evolocumab compared to other lipid-lowering therapies or placebo. An extensive internet-based literature search using pre-determined key phrases supported by medical sub-headings and Boolean operators was performed in October 2022 to identify literature pertinent to the research topic. The search was primarily based on the National Library of Medicine (PubMed and Clinical Trials), MEDLINE, Cochrane, and the Science direct literature databases. Subsequently, the researchers devised PICOs-based screening criteria which had to be met by each identified study for inclusion in the review and meta-analysis. Two independent reviewers conducted data stratification and quality assessment of identified studies. Statistical analysis of the primary and secondary outcomes was conducted on the Cochrane REVMAN 5.4 statistical software for randomized trials.

RESULTS

Two thousand five hundred and seventy-six potential studies were identified for inclusion in the systematic review. Data stratification, screening, and quality assessment of these studies based on the eligibility criteria led to the exclusion of two thousand five hundred and sixty-seven studies as they did not meet the standards set. Nine randomized controlled trials progressed to numerical analysis for validity and reliability. Eight studies were included in the meta-analysis. Meta-analytical results showed a significant decrease in LDL-C changes from initiation of evolocumab therapy to 8 weeks following ACS compared to placebo. Similar results were derived in the sub-acute phase of ACS [SMD -1.95 (95% CI -2.29, -1.62)]. The meta-analysis revealed no statistically significant relationship between the risk of adverse effects, serious adverse effects, and major adverse cardiovascular events (MACE) from treatment using evolocumab in comparison to placebo [(relative risk, RR 1.04 (95% CI 0.99, 1.08) (Z = 1.53; p=0.12)].

CONCLUSION

Early evolocumab therapy initiation was associated with a significant decrease in LDL-C levels and was not associated with an increased risk of adverse effects in comparison to placebo.

Impact of lipid lowering on coronary atherosclerosis moving from the lumen to the artery wall

Randomized clinical trials have demonstrated that increasingly intensive lowering of low-density lipoprotein cholesterol (LDL-C) reduces the rate of cardiovascular events in the primary and secondary prevention setting. Integration of serial coronary imaging within clinical trials has enabled evaluation of medical therapies on the natural history of coronary disease. These studies have extended from early investigation of coronary obstruction with angiography to more contemporary evaluation of plaque burden and composition with imaging modalities that directly visualize the artery wall. The findings of these trials have demonstrated that intensive lipid lowering promotes plaque regression and stabilization. The lessons of this body of research provide a biological rationale underscoring the ability of intensive lipid lowering to reduce cardiovascular risk and have the potential to promote greater uptake in clinical practice.

Effects of PCSK9 Inhibition on Coronary Atherosclerosis Regression of Nontarget Lesions after Primary Percutaneous Coronary Intervention in Acute Coronary Syndrome Patients

Aims

To evaluate the regression of coronary atherosclerosis with proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition in acute coronary syndrome (ACS) patients following primary percutaneous coronary intervention (PPCI). Methods and Result. We examined 40 nontarget lesions in 17 ACS patients who underwent PPCI and were treated with PCSK9 inhibitors. At 1 year, total cholesterol, low-density lipoprotein cholesterol (LDL-C), and atherogenic index (AI) decreased significantly by 2.5 mmol/L, 2.01 mmol/L, and 1.86, respectively. On quantitative coronary angiography, treatment with PCSK9 inhibitors reduced significantly the atherosclerotic area stenosis in nontarget lesions (61.18 ± 14.55 at baseline vs. 52.85 ± 15.51 at 1 year, P < 0.001).

Conclusions

After 1 year of PCSK9 inhibition treatment for ACS patients, the area stenosis of non-TLR was considerably reduced.

Intracoronary Imaging of Vulnerable Plaque-From Clinical Research to Everyday Practice

The introduction into clinical practice of intravascular imaging, including intravascular ultrasound (IVUS), optical coherence tomography (OCT) and their derivatives, allowed for the in vivo assessment of coronary atherosclerosis in humans, including insights into plaque evolution and progression process. Intravascular ultrasound, the most commonly used intravascular modality in many countries, due to its low resolution cannot assess many features of vulnerable plaque such as lipid plaque or thin-cap fibroatheroma. Thus, novel methods were introduced to facilitate this problem including virtual histology intravascular ultrasound and later on near-infrared spectroscopy and OCT. Howbeit, none of the currently used modalities can assess all known characteristics of plaque vulnerability; hence, the idea of combining different intravascular imaging methods has emerged including NIRS-IVUS or OCT-IVUS imaging. All of those described methods may allow us to identify the most vulnerable plaques, which are prone to cause acute coronary syndrome, and thus they may allow us to introduce proper treatment before plaque destabilization.

Additive effects of ezetimibe, evolocumab, and alirocumab on plaque burden and lipid content as assessed by intravascular ultrasound: A PRISMA-compliant meta-analysis

BACKGROUND

The additive effects of ezetimibe, evolocumab or alirocumab on lipid level, plaque volume, and plaque composition using intravascular ultrasound (IVUS) remain unclear.

METHODS

According to the Preferred Reporting Items for Systematic reviews and Meta-Analyses statement, we performed a systematic review and meta-analysis of trials assessing the effects of ezetimibe, evolocumab, and alirocumab on coronary atherosclerosis using IVUS. The primary outcome was change in total atheroma volume (TAV), and the secondary outcomes were changes and differences in plaque composition and lipid content.

RESULTS

Data were collected from 9 trials, involving 917 patients who received ezetimibe, evolocumab or alirocumab in addition to a statin and 919 patients who received statins alone. The pooled estimate demonstrated a significant reduction in TAV with the addition of ezetimibe and favorable effects of evolocumab and alirocumab on TAV. Subgroup analysis also supported favorable effects of evolocumab and alirocumab on TAV, according to baseline TAV, gender, type 2 diabetes mellitus, and prior stain use. Addition of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor to statin therapy resulted in significant reductions in low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), and triglycerides (TG), but not in high-density lipoprotein cholesterol (HDL-C). The pooled estimate also showed significant favorable effects of ezetimibe on LDL-C, TC, and TG, but an insignificant effect on HDL-C. Patients who received ezetimibe showed similar changes in the necrotic core, fibro-fatty plaque, fibrous plaque, and dense calcification compared with patients not treated with ezetimibe.

CONCLUSIONS

The addition of ezetimibe to statin therapy may further reduce plaque and lipid burdens but may not modify plaque composition. Although current evidence supports a similar impact from the addition of PCSK9 inhibitors to statin therapy, more evidence is needed to confirm such an effect.

Recent Advances on the Roles of PCSK-9 Inhibitors in the Management of Acute Ischemic Stroke Patients

Acute ischemic stroke (AIS) represents an important cause of disability and death. Since only a minor percentage of patients with AIS are eligible for acute therapy, the management of risk factors is mandatory. An important risk factor of AIS is hyperlipemia. The current guidelines recommend a strict correction of it. Statins are recommended as the first-line treatment, while proprotein convertase subtilin/kexin type 9 (PCSK-9) inhibitors are administered as a second or even third option when the goal for a low-density lipoprotein cholesterol (LDL-C) level is not achieved. PCSK-9 inhibitors effectively decrease the LDL-C levels through the inhibition of PCSK-9-LDL-receptor complex formation. The in-depth understanding of the PCSK-9 protein mechanism in the metabolism of LDL-C led to the development of effective targeted approaches. Furthermore, a better understanding of the LDL-C metabolic pathway led to the development of newer approaches, which increased the therapeutic options. This article aims to offer an overview of the PCSK-9 inhibitors and their mechanism in reducing the LDL-C levels. Moreover, we will present the main indications of the current guidelines for patients with hyperlipemia and for those who have suffered an acute ischemic stroke, as well as the importance of LDL-C reduction in decreasing the rate of a recurrence.

Intensive lipid lowering agents and coronary atherosclerosis: Insights from intravascular imaging

Advances in intravascular imaging have permitted comprehensive evaluation of coronary atherosclerotic plaque from the perspective of its burden and individual components. These advances have been integrated in clinical trials that have evaluated the impact of intensive lipid lowering regimens. These trials have demonstrated that intensive lipid lowering, using high dose statins as monotherapy and in combination with new lipid lowering agents, produce favorable effects on coronary atheroma, resulting in regression and stabilization. These findings provide important biological insights to understand how intensive lipid lowering may reduce cardiovascular risk. This review aims to provide the reader with a contemporary overview of the findings of these studies and to propose the potential clinical implications for management of higher risk patients with atherosclerotic coronary artery disease.

Smoking and diabetes attenuate beneficial effects of PSCK9 inhibitors on arterial wall properties in patients with very high lipoprotein (a) levels

Background and aims

Elevated lipoprotein (a) (Lp(a)) and low-density lipoprotein cholesterol levels (LDL-C) are significant residual risk factors for cardiovascular events. Treatment with protein convertase subtilisin kexin type 9 (PCSK9) inhibitors reduces the levels of both. Less is known about effects of PCSK9 inhibitors on functional and morphological properties of the arterial wall. The aim of the present study was to determine whether other factors besides decreased LDL-C and Lp(a) are associated with functional (flow-mediated dilation [FMD]) and morphological (carotid intima-media thickness [c-IMT], pulse-wave velocity [PWV]) changes of the arterial wall properties in patients with coronary artery disease (CAD) treated with alirocumab and evolocumab.

Methods

One hundred patients with CAD after myocardial infarction before 55 years and with high Lp(a) were randomised to lipid-lowering therapies without PCSK9 inhibitors (control; N = 31), or with alirocumab 150 mg SC (N = 35) or evolocumab 140 mg SC (N = 34), every 2 weeks. All patients underwent blood sampling for biochemical analyses and ultrasound measurements for FMD, c-IMT and PWV.

Results

There were no significant changes in FMD for the control (10.7% ± 6.6%-11.1% ± 4.4%, p = 0.716) and alirocumab (10.7% ± 5.9%-11.2% ± 5.3%, p = 0.547) groups, while evolocumab promoted significant increase (11.2% ± 6.8%-14.1% ± 6.6%, p < 0.0001). Only in non-smokers and non-diabetics significant improvements in FMD (p < 0.0001) after treatment with PCSK9 inhibitors were observed.

Conclusion

These data show that for patients with CAD and high Lp(a) levels, beneficial effects of PCSK9 inhibitors on the arterial wall properties can be attenuated by specific risk factors, such as smoking and diabetes.

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.

Effect of Alirocumab Added to High-Intensity Statin Therapy on Coronary Atherosclerosis in Patients With Acute Myocardial Infarction: The PACMAN-AMI Randomized Clinical Trial

IMPORTANCE

Coronary plaques that are prone to rupture and cause adverse cardiac events are characterized by large plaque burden, large lipid content, and thin fibrous caps. Statins can halt the progression of coronary atherosclerosis; however, the effect of the proprotein convertase subtilisin kexin type 9 inhibitor alirocumab added to statin therapy on plaque burden and composition remains largely unknown.

OBJECTIVE

To determine the effects of alirocumab on coronary atherosclerosis using serial multimodality intracoronary imaging in patients with acute myocardial infarction.

DESIGN, SETTING, AND PARTICIPANTS

The PACMAN-AMI double-blind, placebo-controlled, randomized clinical trial (enrollment: May 9, 2017, through October 7, 2020; final follow-up: October 13, 2021) enrolled 300 patients undergoing percutaneous coronary intervention for acute myocardial infarction at 9 academic European hospitals.

INTERVENTIONS

Patients were randomized to receive biweekly subcutaneous alirocumab (150 mg; n = 148) or placebo (n = 152), initiated less than 24 hours after urgent percutaneous coronary intervention of the culprit lesion, for 52 weeks in addition to high-intensity statin therapy (rosuvastatin, 20 mg).

MAIN OUTCOMES AND MEASURES

Intravascular ultrasonography (IVUS), near-infrared spectroscopy, and optical coherence tomography were serially performed in the 2 non-infarct-related coronary arteries at baseline and after 52 weeks. The primary efficacy end point was the change in IVUS-derived percent atheroma volume from baseline to week 52. Two powered secondary end points were changes in near-infrared spectroscopy-derived maximum lipid core burden index within 4 mm (higher values indicating greater lipid content) and optical coherence tomography-derived minimal fibrous cap thickness (smaller values indicating thin-capped, vulnerable plaques) from baseline to week 52.

RESULTS

Among 300 randomized patients (mean [SD] age, 58.5 [9.7] years; 56 [18.7%] women; mean [SD] low-density lipoprotein cholesterol level, 152.4 [33.8] mg/dL), 265 (88.3%) underwent serial IVUS imaging in 537 arteries. At 52 weeks, mean change in percent atheroma volume was -2.13% with alirocumab vs -0.92% with placebo (difference, -1.21% [95% CI, -1.78% to -0.65%], P < .001). Mean change in maximum lipid core burden index within 4 mm was -79.42 with alirocumab vs -37.60 with placebo (difference, -41.24 [95% CI, -70.71 to -11.77]; P = .006). Mean change in minimal fibrous cap thickness was 62.67 μm with alirocumab vs 33.19 μm with placebo (difference, 29.65 μm [95% CI, 11.75-47.55]; P = .001). Adverse events occurred in 70.7% of patients treated with alirocumab vs 72.8% of patients receiving placebo.

CONCLUSIONS AND RELEVANCE

Among patients with acute myocardial infarction, the addition of subcutaneous biweekly alirocumab, compared with placebo, to high-intensity statin therapy resulted in significantly greater coronary plaque regression in non-infarct-related arteries after 52 weeks. Further research is needed to understand whether alirocumab improves clinical outcomes in this population.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03067844.

Undertreatment or Overtreatment With Statins: Where Are We?

Statins, in addition to healthy lifestyle interventions, are the cornerstone of lipid-lowering therapy. Other low-density lipoprotein (LDL)-lowering drugs include ezetimibe, bile acid sequestrants, and PCSK9 inhibitors. As new evidence emerges from new clinical trials, therapeutic goals change, leading to renewed clinical guidelines. Nowadays, LDL goals are getting lower, leading to the "lower is better" paradigm in LDL-cholesterol (LDL-C) management. Several observational studies have shown that LDL-C control in real life is suboptimal in both primary and secondary preventions. It is critical to enhance the adherence to guideline recommendations through shared decision-making between clinicians and patients, with patient engagement in selecting interventions based on individual values, preferences, and associated conditions and comorbidities. This narrative review summarizes the evidence regarding the benefits of lipid-lowering drugs in reducing cardiovascular events, the pleiotropic effect of statins, real-world data on overtreatment and undertreatment of lipid-lowering therapies, and the changing LDL-C in targets in the clinical guidelines of dyslipidemias over the years.

Potential of optical coherence tomography and intravascular ultrasound in the detection of vulnerable plaques in coronary arteries

Intravascular imaging of vulnerable plaques in vivo has great potential for predicting coronary events. Currently, there are several methods of intravascular imaging, which make it possible to verify the components of the plaque and, accordingly, its vulnerability. The most common are virtual-histology intravascular ultrasound and optical coherence tomography. Several studies have shown that these imaging techniques can stratify the risk of adverse cardiovascular events, as well as assess the effectiveness of drug therapy. This article will describe the advantages and disadvantages of intravascular ultrasound and optical coherence tomography in identifying vulnerable coronary lesions.

Vulnerable Plaque in Patients with Acute Coronary Syndrome: Identification, Importance, and Management

MI is a leading cause of morbidity and mortality worldwide. Coronary artery thrombosis is the final pathologic feature of the most cases of acute MI primarily caused by atherosclerotic coronary artery disease. The concept of vulnerable plaque has evolved over the years but originated from early pioneering work unveiling the crucial role of plaque rupture and subsequent coronary thrombosis as the dominant cause of MI. Along with systemic cardiovascular risk factors, developments of intravascular and non-invasive imaging modalities have allowed us to identify coronary plaques thought to be at high risk for rupture. However, morphological features alone may only be one of many factors which promote plaque progression. The current vulnerable-plaque-oriented approaches to accomplish personalized risk assessment and treatment have significant room for improvement. In this review, the authors discuss recent advances in the understanding of vulnerable plaque and its management strategy from pathology and clinical perspectives.

Effects of PCSK9 Targeting: Alleviating Oxidation, Inflammation, and Atherosclerosis

Characterized as a chronic inflammatory disease of the large arteries, atherosclerosis is the primary cause of cardiovascular disease, the leading contributor of morbidity and mortality worldwide. Elevated plasma cholesterol levels and chronic inflammation within the arterial plaque are major mediators of plaque initiation, progression, and instability. In 2003, the protein PCSK9 (proprotein convertase subtilisin/kexin 9) was discovered to play a critical role in cholesterol regulation, thus becoming a key player in the mechanisms behind atherosclerotic plaque development. Emerging evidence suggests that PCSK9 could potentially have effects on atherosclerosis that are independent of cholesterol levels. The objective of this review was to discuss the role on PCSK9 in oxidation, inflammation, and atherosclerosis. This function activates proinflammatory cytokine production and affects oxidative modifications within atherosclerotic lesions, revealing its more significant role in atherosclerosis. Although a variety of evidence demonstrates that PCSK9 plays a role in atherosclerotic inflammation, the direct mechanism of involvement is still unknown, driving a gap in knowledge to such a predominant player in cardiovascular disease. Investigation of proteins structurally related to PCSK9 may interestingly be the link in unveiling the mechanistic role of this protein’s involvement in oxidation and inflammation. Importantly, the unique structure of PCSK9 bears structural homology to a one‐of‐a‐kind domain found in the metabolic protein resistin, which is responsible for many of the same inflammatory outcomes as PCSK9. Closing this gap in knowledge of PCSK9`s role in atherosclerotic oxidation and inflammation will provide fundamental information for understanding, preventing, and treating cardiovascular disease.

Short-Term Treatment with Alirocumab, Flow-Dependent Dilatation of the Brachial Artery and Use of Magnetic Resonance Diffusion Tensor Imaging to Evaluate Vascular Structure: An Exploratory Pilot Study

Background: Short-term effects of alirocumab on vascular function have hardly been investigated. Moreover, there is a scarce of reliable non-invasive methods to evaluate atherosclerotic changes of the vasculature. The ALIROCKS trial was performed to address these issues using standard ultrasound-based procedures and a completely novel magnetic resonance-based imaging technique. Methods: A total of 24 patients with an indication for treatment with PCSK9 antibodies were recruited. There were 2 visits to the study site, the first before initiation of treatment with alirocumab and the second after 10 weeks of treatment. The key outcome measures included the change of carotid vessel wall fractional anisotropy, a novel magnetic resonance-based measure of vascular integrity, and the changes of carotid intima-media thickness and flow-dependent dilatation of the brachial artery measured with ultrasound. Results: A total of 19 patients completed the trial, 2 patients stopped treatment, 3 patients did not undergo the second visit due to the COVID pandemic. All of them had atherosclerotic vascular disease. Their mean (standard deviation) LDL-cholesterol concentration was 154 (85) mg/dL at baseline and was reduced by 76 (44) mg/dL in response to alirocumab treatment (p < 0.001, n = 19). P-selectin and vascular endothelial growth factors remained unchanged. Flow-dependent dilatation of the brachial artery (+41%, p = 0.241, n = 18), carotid intima-media thickness (p = 0.914, n = 18), and fractional anisotropy of the carotid artery (p = 0.358, n = 13) also did not significantly change. Conclusion: Despite a nominal amelioration for flow-dependent dilatation, significant effects of short-term treatment with alirocumab on vascular function were not detectable. More work would be needed to evaluate, whether fractional anisotropy may be useful in clinical atherosclerosis research.

An Untargeted Lipidomic Analysis Reveals Depletion of Several Phospholipid Classes in Patients with Familial Hypercholesterolemia on Treatment with Evolocumab

Rationale: Familial hypercholesterolemia (FH) is caused by mutations in genes involved in low-density lipoprotein cholesterol (LDL-C) metabolism, including those for pro-protein convertase subtilisin/kexin type 9 (PCSK-9). The effect of PCSK-9 inhibition on the plasma lipidome has been poorly explored. Objective: Using an ultra-high-performance liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry method, the plasma lipidome of FH subjects before and at different time intervals during treatment with the PCSK-9 inhibitor Evolocumab was explored. Methods and Results: In 25 FH subjects, heterozygotes or compound heterozygotes for different LDL receptor mutations, untargeted lipidomic revealed significant reductions in 26 lipid classes belonging to phosphatidylcholine (PC), sphingomyelin (SM), ceramide (CER), cholesteryl ester (CE), triacylglycerol (TG) and phosphatidylinositol (PI). Lipid changes were graded between baseline and 4- and 12-week treatment. At 12-week treatment, five polyunsaturated diacyl PC, accounting for 38.6 to 49.2% of total PC at baseline; two ether/vinyl ether forms; seven SM; five CER and glucosyl/galactosyl-ceramide (HEX-CER) were reduced, as was the unsaturation index of HEX-CER and lactosyl—CER (LAC-CER). Although non quantitative modifications were observed in phosphatidylethanolamine (PE) during treatment with Evolocumab, shorter and more saturated fatty acyl chains were documented. Conclusions: Depletion of several phospholipid classes occurs in plasma of FH patients during treatment with the PCSK-9 inhibitor Evolocumab. The mechanism underlying these changes likely involves the de novo synthesis of SM and CER through the activation of the key enzyme sphingomyelin synthase by oxidized LDL and argues for a multifaceted system leading to vascular improvement in users of PCSK-9 inhibitors.

The potential targets in immunotherapy of atherosclerosis

Cardiovascular disease is the most common cause of death, which has the highest mortality rate worldwide. Although a diverse range of inflammatory diseases can affect the cardiovascular system, however, heart failure and stroke occur due to atherosclerosis. Atherosclerosis is a chronic autoinflammatory disease of small to large vessels in which different immune mediators are involved in lipid plaque formation and inflammatory vascular remodeling process. A better understanding of the pathophysiology of atherosclerosis may lead to uncovering immunomodulatory therapies. Despite present diagnostic and therapeutic methods, the lack of immunotherapy in the prevention and treatment of atherosclerosis is perceptible. In this review, we will discuss the promising immunological-based therapeutics and novel preventive approaches for atherosclerosis. This study could provide new insights into a better perception of targeted therapeutic pathways and biological therapies.

PoLA/CFPiP/PCS/PSLD/PSD/PSH guidelines on diagnosis and therapy of lipid disorders in Poland 2021

In Poland there are still nearly 20 million individuals with hypercholesterolaemia, most of them are unaware of their condition; that is also why only ca. 5% of patients with familial hypercholesterolaemia have been diagnosed; that is why other rare cholesterol metabolism disorders are so rarely diagnosed in Poland. Let us hope that these guidelines, being an effect of work of experts representing 6 main scientific societies, as well as the network of PoLA lipid centers being a part of the EAS lipid centers, certification of lipidologists by PoLA, or the growing number of centers for rare diseases, with a network planned by the Ministry of Health, improvements in coordinated care for patients after myocardial infarction (KOS-Zawał), reimbursement of innovative agents, as well as introduction in Poland of an effective primary prevention program, will make improvement in relation to these unmet needs in diagnostics and treatment of lipid disorders possible.

High-intensity statin treatment is associated with reduced plaque structural stress and remodelling of artery geometry and plaque architecture

Aims

Plaque structural stress (PSS) is a major cause of atherosclerotic plaque rupture and major adverse cardiovascular events (MACE). We examined the predictors of changes in peak and mean PSS (ΔPSSpeak, ΔPSSmean) in three studies of patients receiving either standard medical or high-intensity statin (HIS) treatment.

Methods and results

We examined changes in PSS, plaque size, and composition between 7348 co-registered baseline and follow-up virtual-histology intravascular ultrasound images in patients receiving standard medical treatment (controls, n = 18) or HIS (atorvastatin 80 mg, n = 20, or rosuvastatin 40 mg, n = 22). The relationship between changes in PSSpeak and plaque burden (PB) differed significantly between HIS and control groups (P < 0.001). Notably, PSSpeak increased significantly in control lesions with PB >60% (P = 0.04), but not with HIS treatment. However, ΔPSSpeak correlated poorly with changes in lumen and plaque area or PB, plaque composition, or lipid lowering. In contrast, ΔPSSpeak correlated significantly with changes in lumen curvature, irregularity, and roughness (P < 0.05), all of which were reduced in HIS patients. ΔPSSmean correlated with changes in lumen area, PA, PB, and circumferential calcification, and was unchanged with either treatment.

Conclusion

Our observational study shows that PSSpeak changes over time were associated with baseline disease severity and treatment. The PSSpeak increase seen in advanced lesions with standard treatment was associated with remodelling artery geometry and plaque architecture, but this was not seen after HIS treatment. Smoothing plaques by reducing plaque/lumen roughness, irregularity, and curvature represents a novel mechanism whereby HIS may reduce PSS and, thus may protect against plaque rupture and MACE.

Proprotein Convertase Subtilisin/Kexin Type 9 and Systemic Inflammatory Biomarker Pentraxin 3 for Risk Stratification Among STEMI Patients Undergoing Primary PCI

Background and Aim

The aim of prospective study was to determine the prognostic value of combined measures of plasma proprotein convertase subtilisin/kexin type 9 (PCSK9) and pentraxin 3 (PTX3) according to the culprit-plaque morphology (plaque rupture versus plaque erosion) in relation to the in patients with acute ST-elevated myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention.

Methods

A total of 434 patients with STEMI aged ≥18 years who underwent pre-intervention OCT imaging of culprit lesions between March 2017 and March 2019 were enrolled. Finally, 235 patients who meet the inclusion criteria were enrolled and the cohort was divided into 3 groups according to PCSK9 and PTX3 levels: group A: PCSK9 < median and Pentraxin 3 (N = 72/30.6%); group B: PCSK9 ≥ median or Pentraxin 3≥ median (N = 91/38.7%); group C: PCSK9 ≥ median and Pentraxin 3≥ median (N = 72/30.6%). MACEs were defined as a composite of all-cause death, myocardial infarction (MI) recurrence, and ischemic stroke, revascularization and heart failure.

Outcomes

During a median follow-up of 2.01 years, 50 patients has occurred MACE. Two-year MACE was higher in group C (23/31.9%) than in group B (16/17.6%) and group A (11/15.3%) (p = 0.028). There was a correlation between PCSK9 and PTX3 (r = 0.302, p < 0.003). In multivariable analysis adjusted for age, gender, risk factors, and serum indexes, being in group C remained independently associated with an increased risk of MACE (hazard ratio [HR]: 2.90; p = 0.010), and group B tended to have higher MACE (HR: 1.76; p = 0.172) compared with group A. Among patients with plaque erosion by OCT, group C was independently associated with an increased risk of MACE (HR: 9.04; p = 0.048) after fully adjustment. However, the significant association was absence among patients with plaque rupture.

Conclusion and Relevance

This study demonstrated the usefulness of combined measures of PCSK9 and PTX3 to enhance risk stratification in patients with STEMI especially among patients with plaque erosion. Patients with elevation of both PCSK9 and PTX3 had a markedly increased risk of MACE.

Effect of alirocumab on coronary plaque in patients with coronary artery disease assessed by optical coherence tomography

BACKGROUND

Proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors have been demonstrated to produce significantly greater reduction in LDL cholesterol levels and cardiovascular events than standard statin therapy. However, evidence on the impact of PCSK9 inhibitors on coronary plaque composition and morphology is limited.

METHODS

In this open-label randomized study, eligible patients with intermediate coronary lesions and elevated LDL cholesterol values were randomized to either alirocumab 75 mg Q2W plus statin (atorvastatin 20 mg/day or rosuvastatin 10 mg/day) therapy or standard care. Optical coherence tomography (OCT) assessments for target lesions were obtained at baseline and at 36 weeks of follow-up.

RESULTS

LDL cholesterol levels were significantly decreased in both the alirocumab and standard care arms, whereas the absolute reduction in LDL cholesterol was significantly greater in patients treated with alirocumab (1.72 ± 0.51 vs. 0.96 ± 0.59, P < 0.0001). Compared with standard care, the addition of alirocumab to statins was associated with significantly greater increases in minimum fibrous cap thickness (18.0 [10.8-29.2] μm vs 13.2 [7.4-18.6] μm; P = 0.029), greater increases in minimum lumen area (0.20[0.10-0.33] mm2 vs 0.13 [0.12-0.24] mm2; P = 0.006) and a greater diminution in maximum lipid arc (15.1̊ [7.8-24.5] vs. 8.4̊ [2.0-10.5]; P = 0.008).

CONCLUSIONS

The addition of alirocumab to statins can not only provide additional LDL cholesterol lowering effects but also have a potential role in promoting a more stable plaque phenotype.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04851769 . Registered 2 Mar 2019.

Lipid-rich plaques detected by near-infrared spectroscopy predict coronary events irrespective of age: A Lipid Rich Plaque sub-study

BACKGROUND AND AIMS

In this Lipid Rich Plaque (LRP) sub-study, 1551 patients undergoing coronary angiography for acute coronary syndromes or stable angina were examined with near-infrared spectroscopy (NIRS) and intravascular ultrasound (IVUS). We aimed to assess the correlation of patient age with the presence of high-risk plaques, defined as maximum 4-mm Lipid Core Burden Index (maxLCBI_4mm) >400 and plaque burden >70%, and 2-year incidence of non-culprit major adverse cardiovascular events (NC-MACE).

METHODS

The study population was divided into four groups according to age: <50 years (122), 50-64 years (700), 65-74 years (502), and ≥75 years (227). The primary outcome was NC-MACE from index procedure to event or the end of the study. Cox regression and mixed-effects Cox regression models were used to assess the effect of age on the association between LCBI and NC-MACE at the patient and plaque levels.

RESULTS

Average maxLCBI_4mm and percentage of patients with at least one segment with maxLCBI_4mm > 400 were similar across the four age groups at both the patient and coronary segment levels. Having at least one segment with maxLCBI_4mm > 400 was strongly associated with NC-MACE, and that association did not differ significantly across age subgroups. Although less common (prevalence of 0.8%-1.3%), a similar trend toward greater NC-MACE rates was seen in patients with plaque burden >70% at the maximum LCBI site across age subgroups.

CONCLUSIONS

Lipid-rich plaques were as frequent in older as in younger patients and predicted a higher incidence of NC-MACE over 2-year follow-up irrespective of age.

Effects of the PCSK9 antibody alirocumab on coronary atherosclerosis in patients with acute myocardial infarction: a serial, multivessel, intravascular ultrasound, near-infrared spectroscopy and optical coherence tomography imaging study-Rationale and design of the PACMAN-AMI trial

BACKGROUND

The risk for cardiovascular adverse events after acute myocardial infarction (AMI) remains high despite potent medical treatment including low-density lipoprotein cholesterol (LDL-C) lowering with statins. Proprotein convertase subtilisin/kexin type 9 (PCSK9) antibodies substantially reduce LDL-C when added to statin. Alirocumab, a monoclonal antibody to PCSK9, reduces major adverse cardiovascular events after AMI. The effects of alirocumab on coronary atherosclerosis including plaque burden, plaque composition and fibrous cap thickness in patients presenting with AMI remains unknown.

AIMS

To determine the effect of LDL-C lowering with alirocumab on top of high-intensity statin therapy on intravascular ultrasound (IVUS)-derived percent atheroma volume (PAV), near-infrared spectroscopy (NIRS)-derived maximum lipid core burden index within 4 mm (maxLCBI_{4 mm}) and optical coherence tomography (OCT)-derived fibrous cap thickness (FCT) in patients with AMI.

METHODS

In this multicenter, double-blind, placebo-controlled trial, 300 patients with AMI (ST-elevation or non-ST-elevation myocardial infarction) were randomly assigned to receive either biweekly subcutaneous alirocumab (150 mg) or placebo beginning <24 hours after the acute event as add-on therapy to rosuvastatin 20 mg. Patients undergo serial IVUS, NIRS and OCT in the two non-infarct related arteries at baseline (at the time of treatment of the culprit lesion) and at 52 weeks. The primary endpoint, change in IVUS-derived PAV, and the powered secondary endpoints, change in NIRS-derived maxLCBI_{4 mm}, and OCT-derived minimal FCT, will be assessed 52 weeks post randomization.

SUMMARY

The PACMAN-AMI trial will determine the effect of alirocumab on top of high-intensity statin therapy on high-risk coronary plaque characteristics as assessed by serial, multimodality intracoronary imaging in patients presenting with AMI.

CLINICAL TRIAL REGISTRATION

NCT03067844.

Discordance in the diagnostic assessment of vulnerable plaques between radiofrequency intravascular ultrasound versus optical coherence tomography among patients with acute myocardial infarction: insights from the IBIS-4 study

We aimed to evaluate the diagnostic agreement between radiofrequency (RF) intravascular ultrasound (IVUS) and optical coherence tomography (OCT) for thin-cap fibroatheroma (TCFA) in non-infarct-related coronary arteries (non-IRA) in patients with ST-segment elevation myocardial infarction (STEMI). In the Integrated Biomarker Imaging Study (IBIS-4), 103 STEMI patients underwent OCT and RF-IVUS imaging of non-IRA after successful primary percutaneous coronary intervention and at 13-month follow-up. A coronary lesion was defined as a segment with ≥ 3 consecutive frames (≈1.2 mm) with plaque burden ≥ 40% as assessed by grayscale IVUS. RF-IVUS-derived TCFA was defined as a lesion with > 10% confluent necrotic core abutting to the lumen in > 10% of the circumference. OCT-TCFA was defined by a minimum cap thickness < 65 μm. The two modalities were matched based on anatomical landmarks using a dedicated matching software. Using grayscale IVUS, we identified 276 lesions at baseline (N = 146) and follow-up (N = 130). Using RF-IVUS, 208 lesions (75.4%) were classified as TCFA. Among them, OCT identified 14 (6.7%) TCFA, 60 (28.8%) thick-cap fibroatheroma (ThCFA), and 134 (64.4%) non-fibroatheroma. All OCT-TCFA (n = 14) were confirmed as RF-TCFA. The concordance rate between RF-IVUS and OCT for TCFA diagnosis was 29.7%. The reasons for discordance were: OCT-ThCFA (25.8%); OCT-fibrous plaque (34.0%); attenuation due to calcium (23.2%); attenuation due to macrophage (10.3%); no significant attenuation (6.7%). There was a notable discordance in the diagnostic assessment of TCFA between RF-IVUS and OCT. The majority of RF-derived TCFA were not categorized as fibroatheroma using OCT, while all OCT-TCFA were classified as TCFA by RF-IVUS.

ClinicalTrials.gov Identifier NCT00962416.

Regression in carotid plaque lipid content and neovasculature with PCSK9 inhibition: A time course study

BACKGROUND AND AIMS

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors reduce cardiovascular events, but their effects on atherosclerotic plaque remain elusive. Using serial magnetic resonance imaging (MRI), we studied changes in carotid plaque lipid content and neovasculature under PCSK9 inhibition with alirocumab.

METHODS

Among patients with low-density lipoprotein cholesterol (LDL-C) ≥70 mg/dl but ineligible for high-dose statin therapy, those with lipid core on carotid MRI were identified to receive alirocumab 150 mg every 2 weeks. Follow-up MRI was performed at 3, 6, and 12 months after treatment. Pre- and post-contrast MRI were acquired to measure percent lipid core volume (% lipid core). Dynamic contrast-enhanced MRI was acquired to measure the extravasation rate of gadolinium contrast (K^trans), a marker of plaque neovasculature.

RESULTS

Of 31 patients enrolled, 27 completed the study (mean age: 69 ± 9; male: 67%). From 9.8% at baseline, % lipid core was progressively reduced to 8.4% at 3 months, 7.5% at 6 months, and 7.2% at 12 months (p = 0.014 for trend), which was accompanied by a progressive increase in % fibrous tissue (p = 0.009) but not % calcification (p = 0.35). K^trans was not reduced until 12 months (from 0.069 ± 0.019 min^-1 to 0.058 ± 0.020 min^-1; p = 0.029). Lumen and wall areas did not change significantly during the study period.

CONCLUSIONS

Regression in plaque composition and neovasculature were observed under PCSK9 inhibition on carotid MRI, which provides unique insight into the biological process of plaque stabilization with disease-modifying therapies.

Low-density lipoproteins cause atherosclerotic cardiovascular disease: pathophysiological, genetic, and therapeutic insights: a consensus statement from the European Atherosclerosis Society Consensus Panel

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Ultrasound Methods in the Evaluation of Atherosclerosis: From Pathophysiology to Clinic

Atherosclerosis is a key pathological process that causes a plethora of pathologies, including coronary artery disease, peripheral artery disease, and ischemic stroke. The silent progression of the atherosclerotic disease prompts for new surveillance tools that can visualize, characterize, and provide a risk evaluation of the atherosclerotic plaque. Conventional ultrasound methods—bright (B)-mode US plus Doppler mode—provide a rapid, cost-efficient way to visualize an established plaque and give a rapid risk stratification of the patient through the Gray–Weale standardization—echolucent plaques with ≥50% stenosis have a significantly greater risk of ipsilateral stroke. Although rather disputed, the measurement of carotid intima-media thickness (C-IMT) may prove useful in identifying subclinical atherosclerosis. In addition, contrast-enhanced ultrasonography (CEUS) allows for a better image resolution and the visualization and quantification of plaque neovascularization, which has been correlated with future cardiovascular events. Newly emerging elastography techniques such as strain elastography and shear-wave elastography add a new dimension to this evaluation—the biomechanics of the arterial wall, which is altered in atherosclerosis. The invasive counterpart, intravascular ultrasound (IVUS), enables an individualized assessment of the anti-atherosclerotic therapies, as well as a direct risk assessment of these lesions through virtual histology IVUS.

Clinical impact of PCSK9 inhibitor on stabilization and regression of lipid-rich coronary plaques: a near-infrared spectroscopy study

AIMS

This study aimed to determine the effects of a proprotein convertase subtilisin-kexin type 9 inhibitor (PCSK9i) on coronary plaque volume and lipid components in patients with a history of coronary artery disease (CAD).

METHODS AND RESULTS

This prospective, open-label, single-centre study analysed non-culprit coronary segments using near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS) at baseline and follow-up angiography. Following changes in the lipid-lowering treatment based on the most recent guideline, the enrolled subjects were divided into two groups: treatment with PCSK9i and statins (PCSK9i: 21 patients and 40 segments) and statins only (control: 32 patients and 50 segments). The absolute and percent LDL-C reductions were significantly greater in the PCSK9i group than in the control group (between group difference: 59.3 mg/dL and 46.4%; P < 0.001 for both). The percent reduction in normalized atheroma volume and absolute reduction in percent atheroma volume (PAV) were also significantly greater in the PCSK9i group (P < 0.001 for both). Furthermore, the PCSK9i group showed greater regression of maximal lipid core burden index for each of the 4-mm segments (maxLCBI4mm) than the control group (57.0 vs. 25.5; P = 0.010). A significant linear correlation was found between the percent changes in LDL-C and maxLCBI4mm (r = 0.318; P = 0.002), alongside the reduction in PAV (r = 0.386; P < 0.001).

CONCLUSION

The lipid component of non-culprit coronary plaques was significantly decreased by PCSK9i. The effects of statin combined with PCSK9i might be attributed to the stabilization and regression of residual vulnerable coronary plaques in patients with CAD.