ST elevation acute myocardial infarction accelerates non-culprit coronary lesion atherosclerosis

Myocardial infarction drives trained immunity of monocytes, accelerating atherosclerosis

BACKGROUND AND AIMS

Survivors of acute coronary syndromes face an elevated risk of recurrent atherosclerosis-related vascular events despite advanced medical treatments. The underlying causes remain unclear. This study aims to investigate whether myocardial infarction (MI)-induced trained immunity in monocytes could sustain proatherogenic traits and expedite atherosclerosis.

METHODS

Apolipoprotein-E deficient (ApoE-/-) mice and adoptive bone marrow transfer chimeric mice underwent MI or myocardial ischaemia-reperfusion (IR). A subsequent 12-week high-fat diet (HFD) regimen was implemented to elucidate the mechanism behind monocyte trained immunity. In addition, classical monocytes were analysed by flow cytometry in the blood of enrolled patients.

RESULTS

In MI and IR mice, blood monocytes and bone marrow-derived macrophages exhibited elevated spleen tyrosine kinase (SYK), lysine methyltransferase 5A (KMT5A), and CCHC-type zinc finger nucleic acid-binding protein (CNBP) expression upon exposure to a HFD or oxidized LDL (oxLDL) stimulation. MI-induced trained immunity was transmissible by transplantation of bone marrow to accelerate atherosclerosis in naive recipients. KMT5A specifically recruited monomethylation of Lys20 of histone H4 (H4K20me) to the gene body of SYK and synergistically transactivated SYK with CNBP. In vivo small interfering RNA (siRNA) inhibition of KMT5A or CNBP potentially slowed post-MI atherosclerosis. Sympathetic denervation with 6-hydroxydopamine reduced atherosclerosis and inflammation after MI. Classical monocytes from ST-elevation MI (STEMI) patients with advanced coronary lesions expressed higher SYK and KMT5A gene levels.

CONCLUSIONS

The findings underscore the crucial role of monocyte trained immunity in accelerated atherosclerosis after MI, implying that SYK in blood classical monocytes may serve as a predictive factor for the progression of atherosclerosis in STEMI patients.

A Potential Role of NFIL3 in Atherosclerosis

Nuclear factor interleukin-3 (NFIL3), a proline- and acidic-residue-rich (PAR) bZIP transcription factor, is called the E4 binding protein 4 (E4BP4) as well, which is relevant to regulate the circadian rhythms and the viability of cells. More and more evidence has shown that NFIL3 is associated with different cardiovascular diseases. In recent years, it has been found that NFIL3 has significant functions in the progression of atherosclerosis (AS) via the regulation of inflammatory response, macrophage polarization, some immune cells and lipid metabolism. In this overview, we sum up the function of NFIL3 during the development of AS and offer meaningful views how to treat cardiovascular disease related to AS.

miR-186-5p Dysregulation in Serum Exosomes from Patients with AMI Aggravates Atherosclerosis via Targeting LOX-1

Purpose

The formation of macrophage-derived foam cells via the uptake of modified lipoproteins is a pivotal development event in atherosclerosis. It has been reported that clinical and experimental myocardial infarction could accelerate atherosclerosis. Several studies have suggested the critical role of exosomes in cardiovascular diseases. However, the role of exosomes from patients with acute myocardial infarction (AMI) patients in atherogenesis remains unclear.

Patients and Methods

Serum exosomes from AMI patients (AMI-Exo) and control individuals (Con-Exo) were isolated and characterized. These exosomes were studied in vitro and in vivo to determine their impact on macrophage foaming and atherogenesis.

Results

Our results showed that AMI-Exo promoted foam cell formation in oxidized low-density lipoprotein (ox-LDL)-treated macrophages and progression of atherosclerosis in high-fat/cholesterol diet-fed ApoE^-/- mice together with a significantly upregulated levels of lectin-like ox-LDL receptor-1 (LOX-1). The miR-186-5p was found to be downregulated in AMI-Exo and macrophages administered with AMI-Exo. Moreover, serum exosomal miR-186-5p achieved high diagnostic performance for AMI. Luciferase reporter assay indicated that miR-186-5p directly inhibited LOX-1. The endogenous or exogenous miR-186-5p deficiency enhanced lipid accumulation by upregulating LOX-1, whereas miR-186-5p mimics had a reverse effect.

Conclusion

In conclusion, the current findings suggest that dysregulated miR-186-5p in AMI-Exo may explain the contribution of acute ischemia events to the advancement of atherosclerosis by enhancing macrophage foaming via its target, LOX-1.

Alarmin-activated B cells accelerate murine atherosclerosis after myocardial infarction via plasma cell-immunoglobulin-dependent mechanisms

AIMS

Myocardial infarction (MI) accelerates atherosclerosis and greatly increases the risk of recurrent cardiovascular events for many years, in particular, strokes and MIs. Because B cell-derived autoantibodies produced in response to MI also persist for years, we investigated the role of B cells in adaptive immune responses to MI.

METHODS AND RESULTS

We used an apolipoprotein-E-deficient (ApoE-/-) mouse model of MI-accelerated atherosclerosis to assess the importance of B cells. One week after inducing MI in atherosclerotic mice, we depleted B cells using an anti-CD20 antibody. This treatment prevented subsequent immunoglobulin G accumulation in plaques and MI-induced accelerated atherosclerosis. In gain of function experiments, we purified spleen B cells from mice 1 week after inducing MI and transferred these cells into atherosclerotic ApoE-/- mice, which greatly increased immunoglobulin G (IgG) accumulation in plaque and accelerated atherosclerosis. These B cells expressed many cytokines that promote humoural immunity and in addition, they formed germinal centres within the spleen where they differentiated into antibody-producing plasma cells. Specifically deleting Blimp-1 in B cells, the transcriptional regulator that drives their terminal differentiation into antibody-producing plasma cells prevented MI-accelerated atherosclerosis. Alarmins released from infarcted hearts were responsible for activating B cells via toll-like receptors and deleting MyD88, the canonical adaptor protein for inflammatory signalling downstream of toll-like receptors, prevented B-cell activation and MI-accelerated atherosclerosis.

CONCLUSION

Our data implicate early B-cell activation and autoantibodies as a central cause for accelerated atherosclerosis post-MI and identifies novel therapeutic strategies towards preventing recurrent cardiovascular events such as MI and stroke.

Pravastatin attenuates atherosclerosis after myocardial infarction by inhibiting inflammatory Ly6Chigh monocytosis in apolipoprotein E knockout mice

Objective

To evaluate the protective effect of pravastatin on atherosclerotic development and inflammatory monocyte subset in atherosclerotic apolipoprotein E (ApoE)^−/− mice after myocardial infarction (MI).

Methods

Male ApoE^−/− mice (8 weeks old) were fed a high-fat diet for 14 weeks throughout the experiment. A MI model was produced using 18-week-old ApoE^−/− mice. They were randomly divided into three groups: sham group, MI group, and MI+Pra group (40 mg/kg/day pravastatin). After 4 weeks (at the end of the study period), the mice were sacrificed and cardiac function was evaluated by echocardiography. Aortic lesion areas were evaluated using oil red O staining. Plaque macrophage in aortic sinus was analyzed by immunofluorescence staining. Flow cytometry was used to explore the proportions of monocyte subsets in the blood, spleen, and bone marrow．

Results

Pravastatin improved cardiac function and reduced lesion areas. It also attenuated the supply of monocytes in spleen, especially the inflammatory Ly6C^high monocyte subset. Pravastatin also subsequently reduced macrophage accumulation in atherosclerotic lesions.

Conclusions

MI accelerated chronic atherosclerosis progress. Pravastatin suppressed atherosclerotic development and inhibited inflammatory monocytosis after MI in ApoE^−/− mice.

Instantaneous wave-free ratio guided multivessel revascularisation during percutaneous coronary intervention for acute myocardial infarction: study protocol of the randomised controlled iMODERN trial

INTRODUCTION

Recent randomised clinical trials showed benefit of non-culprit lesion revascularisation in ST-elevation myocardial infarction (STEMI) patients. However, it remains unclear whether revascularisation should be performed at the index procedure or at a later stage.

METHODS AND ANALYSIS

The instantaneous wave-free ratio (iFR) Guided Multivessel Revascularisation During Percutaneous Coronary Intervention for Acute Myocardial Infarction trial is a multicentre, randomised controlled prospective open-label trial with blinded evaluation of endpoints. After successful primary percutaneous coronary intervention (PCI), eligible STEMI patients with residual non-culprit lesions are randomised, to instantaneous wave-free ratio guided treatment of non-culprit lesions during the index procedure versus deferred cardiac MR-guided management within 4 days to 6 weeks. The primary endpoint of the study is the combined occurrence of all-cause death, recurrent myocardial infarction and hospitalisation for heart failure at 12 months follow-up. Clinical follow-up includes questionnaires at 3 months and outpatient visits at 6 months and 12 months after primary PCI. Furthermore, a cost-effectiveness analysis will be performed.

ETHICS AND DISSEMINATION

Permission to conduct this trial has been granted by the Medical Ethical Committee of the Amsterdam University Medical Centres (loc. VUmc, ID NL60107.029.16). The primary results of this trial will be shared in a main article and subgroup analyses or spin-off studies will be shared in secondary papers.

TRIAL REGISTRATION NUMBER

NCT03298659.

Eosinophil percentage as a new prognostic marker in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

Background

In addition to proinflammatory properties, eosinophils can stimulate platelet activation and enhance prothrombotic pathways. In this study, we aimed to investigate the association between the eosinophil percentage (EOS%) and major adverse cardiac events (MACE) in patients with ST-segment elevation myocardial infarction (STEMI).

Methods

This study enrolled a total of 1,909 patients who were diagnosed with STEMI. Ventricular arrhythmia, reinfarction, the need for cardiopulmonary resuscitation, target vessel revascularization, congestive heart failure, and cardiovascular mortality during index hospitalization were defined as MACE.

Results

Three hundred and eighty patients (19.7%) reached the combined endpoint with MACE. The rates of inhospital mortality and MACE were significantly higher in low EOS% group as compared to high EOS% group (4% vs. 1.1%, p < 0.01 and 32.8% vs. 11.3%, p < 0.01, respectively). On multivariate logistic regression analyses, EOS% (OR = 0.44, p < 0.01) was found to be one of the independent predictors of MACE. The EOS% lower than 0.60 on admission predicted inhospital MACE with a sensitivity of 68% and a specificity of 72% (AUC: 0.684, p < 0.01).

Conclusions

Low EOS% on admission may be associated with high inhospital MACE in STEMI patients. EOS% may be used as a novel biomarker for risk stratification of these patients.

Hematopoiesis and Cardiovascular Disease

A central feature of atherosclerosis, the most prevalent chronic vascular disease and root cause of myocardial infarction and stroke, is leukocyte accumulation in the arterial wall. These crucial immune cells are produced in specialized niches in the bone marrow, where a complex cell network orchestrates their production and release. A growing body of clinical studies has documented a correlation between leukocyte numbers and cardiovascular disease risk. Understanding how leukocytes are produced and how they contribute to atherosclerosis and its complications is, therefore, critical to understanding and treating the disease. In this review, we focus on the key cells and products that regulate hematopoiesis under homeostatic conditions, during atherosclerosis and after myocardial infarction.

Inflammation in atherosclerotic cardiovascular disease

Atherosclerotic cardiovascular disease is a leading cause of death and morbidity globally. Over the past several years, arterial inflammation has been implicated in the pathophysiology of athero-thrombosis, substantially confirming what pathologist Rudolf Virchow had observed in the 19th century. Lipid lowering, lifestyle changes, and modification of other risk factors have reduced cardiovascular complications of athero-thrombosis, but a substantial residual risk remains. In view of the pathogenic role of inflammation in athero-thrombosis, directly targeting inflammation has emerged as an additional potential therapeutic option; and some early promising results have been suggested by the Canakinumab Anti-inflammatory Thrombosis Outcome Study (CANTOS), in which canakinumab, a fully human monoclonal antibody targeting the pro-inflammatory and pro-atherogenic cytokine interleukin 1 beta, was shown to reduce cardiovascular events.

Angiography-guided Multivessel Percutaneous Coronary Intervention Versus Ischemia-guided Percutaneous Coronary Intervention Versus Medical Therapy in the Management of Significant Disease in Non-Infarct-related Arteries in ST-Elevation Myocardial Infarction Patients With Multivessel Coronary Disease

BACKGROUND

In ST-elevation myocardial infarction (STEMI) patients with multivessel (MV) disease, after primary percutaneous coronary intervention (PCI), emerging evidence suggests that significant disease in non-infarct-related coronary arteries (IRAs) should be routinely stented. Whether this procedure should be guided by angiography alone or ischemia testing is unclear.

METHODS

All STEMI patients treated with primary PCI between January 1, 2005, and December 31, 2012, at a tertiary cardiology center were reviewed retrospectively. Inclusion criterion is patients with at least 70% stenosis in non-IRAs. There were 3 treatment groups: (1) angiography-guided MV-PCI, (2) ischemia-guided PCI, and (3) medical therapy. Primary endpoint is all-cause mortality, and secondary end point is major adverse cardiovascular events (MACE), including death, acute coronary syndrome, revascularization, or stent thrombosis. Event-free survivals were compared using multivariate Cox proportional-hazards analysis. A propensity score-adjusted analysis was performed.

RESULTS

Four hundred forty-seven STEMI patients had >70% stenosis in non-IRAs. For all-cause mortality, the 3 strategies did not differ. For MACE, ischemia-guided PCI was associated with the lowest MACE rate, followed by angiography-guided PCI and medical therapy, which was associated with the highest MACE rate, driven by death and myocardial infarction. Hazard ratios (HRs) for MACE: angiography-guided MV-PCI versus ischemia-guided MV-PCI: HR = 2.23 [95% confidence interval (CI), 1.11-4.48; P = 0.023]; medical therapy versus angiography-guided MV-PCI: HR = 1.58 (95% CI, 0.99-2.63; P = 0.062); medical therapy versus ischemia-guided MV-PCI: HR = 1.72 (95% CI, 1.08-2.74; P = 0.022). Propensity score-adjusted analysis yielded similar results.

CONCLUSIONS

After primary PCI, complete revascularization in STEMI multivessel disease is associated with lower MACE rates than medical therapy. However, ischemia-testing-guided rather than angiography-guided revascularization was associated with the lowest MACE. This study provides preliminary data and hypotheses for future randomized controlled studies.

Inflammation, infection and atherosclerosis

Atherosclerotic cardiovascular disease is a leading cause of death in much of the world. Adoption of a healthy lifestyle and cholesterol lowering are the key measures used to prevent major complications of atherosclerosis. Recent data have identified a critical role for inflammation mediated through activation of both innate and adaptive immune pathways in the pathophysiology of atherosclerosis opening up opportunities for development of anti-inflammatory interventions that could supplement risk factor modification and lipid lowering as an approach to further reducing the burden of atherosclerotic cardiovascular disease.

Twelve-month clinical outcomes of acute non-ST versus ST-segment elevation myocardial infarction patients with reduced preprocedural thrombolysis in myocardial infarction flow undergoing percutaneous coronary intervention

BACKGROUND

Reduced preprocedural thrombolysis in myocardial infarction (TIMI) flow in patients with ST-segment elevation myocardial infarction (STEMI) is known to be associated with increased mortality. However, clinical implications of reduced preprocedural TIMI flow in patients with non-ST-segment elevation myocardial infarction (NSTEMI) have not been fully elucidated as yet. The aim of the present study was to compare the clinical influence of reduced preprocedural TIMI flows between patients with STEMI and NSTEMI undergoing percutaneous coronary intervention (PCI).

METHODS

From the Korea Acute Myocardial Infarction Registry, a total of 7336 AMI patients with angiographically confirmed reduced preprocedural TIMI flow (TIMI 0/1) during PCI were selected and divided into STEMI (n=4852) and NSTEMI (n=2484) groups. The 12-month composite of total death, nonfatal myocardial infarction, coronary artery bypass graft, and repeated PCI was compared between the two groups.

RESULTS

After adjustment of baseline confounders by propensity score stratification, the NSTEMI group had lower incidences of major adverse cardiac events than the STEMI group (7.15 vs. 11.19%; hazard ratio: 0.63; 95% confidence interval: 0.47-0.84; P=0.001) at 12 months, which was largely attributable to the lower incidences of total deaths (2.43 vs. 3.99%; P=0.04) and repeated PCI (3.81 vs. 6.41%; P=0.01).

CONCLUSION

Among AMI patients with TIMI 0/1, patients with NSTEMI had better outcomes compared with those of patients with STEMI on the basis of the incidences of 12-month outcomes. This could be attributable to lower total death and repeated revascularization in patients with NSTEMI.

Postnatal undernutrition in mice causes cardiac arrhythmogenesis which is exacerbated when pharmacologically stressed

Growth restriction caused by postnatal undernutrition increases risk for cardiovascular disease in adulthood with the potential to induce arrhythmogenesis. Thus, the purpose was to determine if undernutrition during development produced arrhythmias at rest and when stressed with dobutamine in adulthood. Mouse dams were fed (CON: 20% protein), or low-protein (LP: 8%) diet before mating. A cross-fostering model was used where pups nursed by dams fed LP diet in early [EUN; postnatal day (PN) 1–10], late (LUN; PN11–21) and whole (PUN; 1–21) phases of postnatal life. Weaned pups were switched to CON diets for the remainder of the study (PN80). At PN80, body composition (magnetic resonance imaging), and quantitative electrocardiogram (ECG) measurements were obtained under 1% isoflurane anesthesia. After baseline ECG, an IP injection (1.5 µg/g body weight) of dobutamine was administered and ECG repeated. Undernutrition significantly (P<0.05) reduced body weight in LUN (22.68±0.88 g) and PUN (19.96±0.32 g) but not in CON (25.05±0.96 g) and EUN (25.28±0.9207 g). Fat mass decreased in all groups compared with controls (CON: 8.00±1.2 g, EUN: 6.32±0.65 g, LUN: 5.11±1.1 g, PUN: 3.90±0.25 g). Lean mass was only significantly reduced in PUN (CON: 17.99±0.26 g, EUN: 17.78±0.39 g, LUN: 17.34±0.33 g, PUN: 15.85±0.28 g). Absolute heart weights were significantly less from CON, with PUN having the smallest. ECG showed LUN had occurrences of atrial fibrillation; EUN had increases of 1st degree atrioventricular block upon stimulation, and PUN had increased risk for ventricular depolarization arrhythmias. CON did not display arrhythmias. Undernutrition in early life resulted in ventricular arrhythmias under stressed conditions, but undernutrition occurring in later postnatal life there is an increased incidence of atrial arrhythmias.

Protective role of melatonin in cardiac ischemia-reperfusion injury: From pathogenesis to targeted therapy

Acute myocardial infarction (MI) is a major cause of mortality and disability worldwide. In patients with MI, the treatment option for reducing acute myocardial ischemic injury and limiting MI size is timely and effective myocardial reperfusion using either thombolytic therapy or primary percutaneous coronary intervention (PCI). However, the procedure of reperfusion itself induces cardiomyocyte death, known as myocardial reperfusion injury, for which there is still no effective therapy. Recent evidence has depicted a promising role of melatonin, which possesses powerful antioxidative and anti-inflammatory properties, in the prevention of ischemia-reperfusion (IR) injury and the protection against cardiomyocyte death. A number of reports explored the mechanism of action behind melatonin-induced beneficial effects against myocardial IR injury. In this review, we summarize the research progress related to IR injury and discuss the unique actions of melatonin as a protective agent. Furthermore, the possible mechanisms responsible for the myocardial benefits of melatonin against reperfusion injury are listed with the prospect of the use of melatonin in clinical application.

Melatonin suppresses platelet activation and function against cardiac ischemia/reperfusion injury via PPARγ/FUNDC1/mitophagy pathways

Platelet activation is a major (patho-) physiological mechanism that underlies ischemia/reperfusion (I/R) injury. In this study, we explored the molecular signals for platelet hyperactivity and investigated the beneficial effects of melatonin on platelet reactivity in response to I/R injury. After reperfusion, peroxisome proliferator-activated receptor γ (PPARγ) was progressively downregulated in patients with acute myocardial infarction undergoing coronary artery bypass grafting (CABG) surgery and in mice with I/R injury model. Loss of PPARγ was closely associated with FUN14 domain containing 1 (FUNDC1) dephosphorylation and mitophagy activation, leading to increased mitochondrial electron transport chain complex (ETC.) activity, enhanced mitochondrial respiratory function, and elevated ATP production. The improved mitochondrial function strongly contributed to platelet aggregation, spreading, expression of P-selectin, and final formation of micro-thromboses, eventually resulting in myocardial dysfunction and microvascular structural destruction. However, melatonin powerfully suppressed platelet activation via restoration of the PPARγ content in platelets, which subsequently blocked FUNDC1-required mitophagy, mitochondrial energy production, platelet hyperactivity, and cardiac I/R injury. In contrast, genetic ablation of PPARγ in platelet abolished the beneficial effects of melatonin on mitophagy, mitochondrial ATP supply, and platelet activation. Our results lay the foundation for the molecular mechanism of platelet activation in response to I/R injury and highlight that the manipulation of the PPARγ/FUNDC1/mitophagy pathway by melatonin could be a novel strategy for cardioprotection in the setting of cardiac I/R injury.

Inflammation - Cause or Consequence of Heart Failure or Both?

PURPOSE OF REVIEW

With the intention to summarize the currently available evidence on the pathophysiological relevance of inflammation in heart failure, this review addresses the question whether inflammation is a cause or consequence of heart failure, or both.

RECENT FINDINGS

This review discusses the diversity (sterile, para-inflammation, chronic inflammation) and sources of inflammation and gives an overview of how inflammation (local versus systemic) can trigger heart failure. On the other hand, the review is outlined how heart failure-associated wall stress and signals released by stressed, malfunctioning, or dead cells (DAMPs: e.g., mitochondrial DNA, ATP, S100A8, matricellular proteins) induce cardiac sterile inflammation and how heart failure provokes inflammation in various peripheral tissues in a direct (inflammatory) and indirect (hemodynamic) manner. The crosstalk between the heart and peripheral organs (bone marrow, spleen, gut, adipose tissue) is outlined and the importance of neurohormonal mechanisms including the renin angiotensin aldosteron system and the ß-adrenergic nervous system in inflammation and heart failure is discussed. Inflammation and heart failure are strongly interconnected and mutually reinforce each other. This indicates the difficulty to counteract inflammation and heart failure once this chronic vicious circle has started and points out the need to control the inflammatory process at an early stage avoiding chronic inflammation and heart failure. The diversity of inflammation further addresses the need for a tailored characterization of inflammation enabling differentiation of inflammation and subsequent target-specific strategies. It is expected that the characterization of the systemic and/or cardiac immune profile will be part of precision medicine in the future of cardiology.

Prolonged Fever After ST-Segment Elevation Myocardial Infarction and Long-Term Cardiac Outcomes

Background

The biphasic inflammation after ST‐segment elevation myocardial infarction (STEMI) plays an important role in myocardial healing and progression of systemic atherosclerosis. The purpose of this study is to investigate the impact of fever during the first and second phases of post‐STEMI inflammation on long‐term cardiac outcomes.

Methods and Results

A total of 550 patients with STEMI were enrolled in this study. Axillary body temperature (BT) was measured and maximum BTs were determined for the first (within 3 days: max‐BT_1–3d) and second (from 4 to 10 days after admission: max‐BT_4–10d) phases, respectively. Patients were followed for cardiac events (cardiovascular death, acute coronary syndrome, and rehospitalization for heart failure) for a median 5.3 years. During the follow‐up period, 80 patients experienced cardiac events. A high max‐BT_4–10d was strongly associated with long‐term cardiac events (hazard ratio, 95% CI) for a 1°C increase in the max‐BT_4–10d: 2.834 (2.017–3.828), P<0.0001, whereas the max‐BT_1–3d was not associated with cardiac events (1.136 [0.731–1.742], P=0.57). Even after adjustment for coronary risk factors, estimated glomerular filtration rate, infarct size, pericardial effusion, and medications on discharge, fever during the second phase (max‐BT_4–10d ≥37.1°C) was significantly associated with future cardiac events (hazard ratio [95% CI] 2.900 [1.710–5.143], P<0.0001).

Conclusions

Fever during the second phase but not the first phase of post‐STEMI inflammation was a strong associated factor with worse long‐term cardiac outcomes in patients after STEMI, suggesting the need to consider the optimal timing for anti‐inflammatory strategies after STEMI.

Epicardial adipose tissue is associated with high-risk plaque feature progression in non-culprit lesions

Several studies have suggested a link between epicardial adipose tissue (EAT) volume and high-risk plaques (HRPs); however, little is known about the association between EAT volume and HRP progression in non-culprit lesions (NCLs). Therefore, we evaluated whether EAT can independently predict HRP characteristic progression in NCLs by coronary computed tomography angiography (CCTA). In this single-centre trial, we analysed 131 consecutive patients (median age 61 years, male 72.52%) undergoing CCTA with percutaneous coronary intervention (PCI) for culprit lesions. All patients were scheduled to undergo follow-up CCTA 12 months after PCI. HRP features, including positive remodelling, low attenuation plaque, spotty calcification, and napkin-ring sign, along with EAT volume, were assessed by CCTA. The numbers of HRP features were compared between baseline and follow-up CCTA to detect HRP progression in NCLs, and patients were classified into two groups based on HRP progression. Logistic regression analysis was used to evaluate whether EAT volume was independently associated with HRP progression in NCLs. Overall, 23 of 131 patients who underwent two CCTAs exhibited HRP progression in NCLs (17.6%). Logistic regression analysis showed that a higher baseline EAT volume was associated with NCL HRP progression (odds ratio 1.019, 95% confidence interval 1.009-1.029, P < 0.001). The cut-off value for baseline EAT volume for NCL HRP progression was 107 ml based on receiver-operator characteristic curve analyses, and the area under the curve was 0.66. Baseline EAT volume was identified as an independent predictor of NCL HRP progression.

Characteristics Detected on Computed Tomography Angiography Predict Coronary Artery Plaque Progression in Non-Culprit Lesions

Objective

This study sought to determine whether variables detected on coronary computed tomography angiography (CCTA) would predict plaque progression in non-culprit lesions (NCL).

Materials and Methods

In this single-center trial, we analyzed 103 consecutive patients who were undergoing CCTA and percutaneous coronary intervention (PCI) for culprit lesions. Follow-up CCTA was scheduled 12 months after the PCI, and all patients were followed for 3 years after their second CCTA examination. High-risk plaque features and epicardial adipose tissue (EAT) volume were assessed by CCTA. Each NCL stenosis grade was compared visually between two CCTA scans to detect plaque progression, and patients were stratified into two groups based on this. Logistic regression analysis was used to evaluate the factors that were independently associated with plaque progression in NCLs. Time-to-event curves were compared using the log-rank statistic.

Results

Overall, 34 of 103 patients exhibited NCL plaque progression (33%). Logistic regression analyses showed that the NCL progression was associated with a history of ST-elevated myocardial infarction (odds ratio [OR] = 5.855, 95% confidence interval [CI] = 1.391–24.635, p = 0.016), follow-up low-density lipoprotein cholesterol level (OR = 6.832, 95% CI = 2.103–22.200, p = 0.001), baseline low-attenuation plaque (OR = 7.311, 95% CI = 1.242–43.028, p = 0.028) and EAT (OR = 1.015, 95% CI = 1.000–1.029, p = 0.044). Following the second CCTA examination, major adverse cardiac events (MACEs) were observed in 12 patients, and NCL plaque progression was significantly associated with future MACEs (log rank p = 0.006).

Conclusion

Noninvasive assessment of NCLs by CCTA has potential prognostic value.

E-Selectin Inhibition Mitigates Splenic HSC Activation and Myelopoiesis in Hypercholesterolemic Mice With Myocardial Infarction

OBJECTIVE

Atherosclerosis is a chronic disease characterized by lipid accumulation in the arterial wall. After myocardial infarction (MI), atherosclerotic plaques are infiltrated by inflammatory myeloid cells that aggravate the disease and increase the risk of secondary myocardial ischemia. Splenic myelopoiesis provides a steady flow of myeloid cells to inflamed atherosclerotic lesions after MI. Therefore, targeting myeloid cell production in the spleen could ameliorate increased atherosclerotic plaque inflammation after MI.

APPROACH AND RESULTS

Here we show that MI increases splenic myelopoiesis by driving hematopoietic stem and progenitor cells into the cell cycle. In an atherosclerotic mouse model, E-selectin inhibition decreased hematopoietic stem and progenitor cell proliferation in the spleen after MI. This led to reduced extramedullary myelopoiesis and decreased myeloid cell accumulation in atherosclerotic lesions. Finally, we observed stable atherosclerotic plaque features, including smaller plaque size, reduced necrotic core area, and thicker fibrous cap after E-selectin inhibition.

CONCLUSIONS

Inhibiting E-selectin attenuated inflammation in atherosclerotic plaques, likely by reducing leukocyte recruitment into plaques and by mitigating hematopoietic stem and progenitor cell activation in the spleen of mice with MI.

Homocysteine is associated with the progression of non-culprit coronary lesions in elderly acute coronary syndrome patients after percutaneous coronary intervention

BACKGROUND

The influence of homocysteine (Hcy) on the migration and proliferation of vascular smooth muscle cells has been well established. However, the impact of Hcy levels on the progression of non-culprit coronary lesions (NCCLs) is controversial. This study aims to evaluate whether the plasma level of Hcy is related to the progression of NCCLs after percutaneous coronary stent implantation in elderly patients with acute coronary syndrome (ACS).

METHODS

A total of 223 elderly patients (≥ 65 years old) with ACS undergoing stent implantation and follow-up coronary angiography were enrolled. Laboratory determination comprised of blood sample evaluation for Hcy was carried out before baseline coronary intervention. The patients were classified into two groups according to the blood Hcy tertiles (≥ 15 mmol/L or < 15 mmol/L). Patients were followed up for 12.2 months. NCCL progression was assessed by three-dimensional quantitative coronary angiography.

RESULTS

A significantly higher ratio of NCCL progression was observed in the group with baseline Hcy concentrations above 15 mmol/L compared to the group with concentrations below 15 mmol/L (41/127, 32.3% vs. 14/96, 14.6%, P = 0.002). Multivariate Cox regression analysis showed that Hcy and diabetes mellitus were independent risk factors for NCCL progression. The crude hazard ratio (HR) of NCCL progression for Hcy level was 1.056 (95% CI: 1.01-1.104, P = 0.015). The adjusted HR of NCCL progression for Hcy level was 1.024 (95% CI: 1.007-1.042, P = 0.007). The adjusted HR of NCCL progression for diabetes mellitus was 1.992 (95% CI: 1.15-3.44, P = 0.013).

CONCLUSIONS

Hcy is an independent risk factor for NCCL progression after 12 months of follow-up in elderly patients with ACS who has undergone percutaneous coronary stenting.

Changes of coronary plaque composition correlate with C-reactive protein levels in patients with ST-elevation myocardial infarction following high-intensity statin therapy

OBJECTIVES

Levels of inflammatory biomarkers associate with changes of coronary atheroma burden in statin-treated patients with stable coronary artery disease. This study sought to determine changes of plaque composition in vivo in relation to high-sensitivity C-reactive protein (hs-CRP) levels in patients with ST-elevation myocardial infarction (STEMI) receiving high-intensity statin therapy.

METHODS

The IBIS-4 study performed serial (baseline and 13-month), 2-vessel intravascular ultrasound (IVUS) and radiofrequency-IVUS of the non-infarct-related arteries in patients with STEMI treated with high-intensity statin therapy. The present analysis included 44 patients (80 arteries) with serial measurements of hs-CRP.

RESULTS

At follow-up, median low-density lipoprotein cholesterol (LDL-C) levels decreased from 126 to 77 mg/dl, HDL-C increased from 44 to 47 mg/dl, and hs-CRP decreased from 1.6 to 0.7 mg/L. Regression of percent atheroma volume (-0.99%, 95% CI -1.84 to -0.14, p = 0.024) was accompanied by reduction of percent fibro-fatty (p = 0.04) and fibrous tissue (p < 0.001), and increase in percent necrotic core (p = 0.006) and dense calcium (p < 0.001). Follow-up levels of hs-CRP, but not LDL-C, correlated with changes in percent necrotic core (p = 0.001) and inversely with percent fibrous tissue volume (p = 0.008). Similarly, baseline-to-follow-up change of hs-CRP correlated with the change in percent necrotic core volume (p = 0.02).

CONCLUSIONS

In STEMI patients receiving high-intensity statin therapy, stabilization of VH-IVUS-defined necrotic core was confined to patients with lowest on-treatment levels and greatest reduction of hs-CRP. Elevated CRP levels at follow-up may identify progression of high-risk coronary plaque composition despite intensive statin therapy and overall regression of atheroma volume.

Efficacy study of olmesartan medoxomil on coronary atherosclerosis progression and epicardial adipose tissue volume reduction in patients with coronary atherosclerosis detected by coronary computed tomography angiography: study protocol for a randomized controlled trial

Background

Epicardial adipose tissue (EAT) is a newly discovered independent risk factor for coronary atherosclerosis. There is a scarcity of information on the reduction of EAT volume to reduce atherosclerosis risk. Coronary computed tomography angiography (CCTA) has emerged as a noninvasive imaging method for the analysis of coronary atherosclerosis and EAT volume. The purpose of this trial is to determine whether olmesartan medoxomil is effective at both treatment of coronary atherosclerosis progression and EAT volume reduction in patients with coronary atherosclerosis detected by CCTA.

Methods/design

This study is a prospective, single-center, open-label, randomized controlled clinical trial aimed at exploring the efficacy of olmesartan medoxomil on coronary atherosclerosis and EAT. A total of 194 patients with coronary stenosis greater than 30 % and less than 70 % detected by CCTA will be randomly divided into olmesartan medoxomil or conventional antihypertensive medication groups (1:1 ratio). The primary outcome measures include coronary atherosclerosis progression and EAT volume reduction, as detected by CCTA at 12 months. The secondary outcome measures include the levels of blood lipids, glucose, high-sensitivity C-reactive protein, IL-6, monocyte chemotactic protein 1, TNF-α, matrix metalloproteinase 9, NO, endothelin 1, adiponectin, and leptin at baseline and after 6 and 12 months.

Discussion

Treatments aimed at reducing EAT volume can eventually achieve an antiatherosclerotic effect. This is the first trial designed to explore the effect of olmesartan medoxomil on both coronary atherosclerosis progression and EAT volume reduction in patients with coronary atherosclerosis detected by CCTA.

Trial registration

ClinicalTrials.gov: NCT02360956.

Innate immune cells in ischaemic heart disease: does myocardial infarction beget myocardial infarction?

Knowledge of macrophages in steady-state and diseased tissue is rapidly expanding, propelled by improved diagnostic capacity to detect and monitor cells in their native environments. In this review, we discuss implications for ischaemic heart disease and examine innate immune cell pathways that increase systemic leucocyte supply after myocardial infarction (MI). Acute MI alters the macrophage phenotype and supply chain from tissue resident to blood monocytes sourced from haematopoietic organs. That blood leucocytosis closely associates with cardiovascular mortality provides a strong motivation to understand why and how organ ischaemia alters cellular immunity.

Systemic Atherosclerotic Inflammation Following Acute Myocardial Infarction: Myocardial Infarction Begets Myocardial Infarction

BACKGROUND

Preclinical data suggest that an acute inflammatory response following myocardial infarction (MI) accelerates systemic atherosclerosis. Using combined positron emission and computed tomography, we investigated whether this phenomenon occurs in humans.

METHODS AND RESULTS

Overall, 40 patients with MI and 40 with stable angina underwent thoracic 18F-fluorodeoxyglucose combined positron emission and computed tomography scan. Radiotracer uptake was measured in aortic atheroma and nonvascular tissue (paraspinal muscle). In 1003 patients enrolled in the Global Registry of Acute Coronary Events, we assessed whether infarct size predicted early (≤30 days) and late (>30 days) recurrent coronary events. Compared with patients with stable angina, patients with MI had higher aortic 18F-fluorodeoxyglucose uptake (tissue-to-background ratio 2.15±0.30 versus 1.84±0.18, P<0.0001) and plasma C-reactive protein concentrations (6.50 [2.00 to 12.75] versus 2.00 [0.50 to 4.00] mg/dL, P=0.0005) despite having similar aortic (P=0.12) and less coronary (P=0.006) atherosclerotic burden and similar paraspinal muscular 18F-fluorodeoxyglucose uptake (P=0.52). Patients with ST-segment elevation MI had larger infarcts (peak plasma troponin 32 300 [10 200 to >50 000] versus 3800 [1000 to 9200] ng/L, P<0.0001) and greater aortic 18F-fluorodeoxyglucose uptake (2.24±0.32 versus 2.02±0.21, P=0.03) than those with non-ST-segment elevation MI. Peak plasma troponin concentrations correlated with aortic 18F-fluorodeoxyglucose uptake (r=0.43, P=0.01) and, on multivariate analysis, independently predicted early (tertile 3 versus tertile 1: relative risk 4.40 [95% CI 1.90 to 10.19], P=0.001), but not late, recurrent MI.

CONCLUSIONS

The presence and extent of MI is associated with increased aortic atherosclerotic inflammation and early recurrent MI. This finding supports the hypothesis that acute MI exacerbates systemic atherosclerotic inflammation and remote plaque destabilization: MI begets MI.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01749254.

Acute Myocardial Infarction Is a Risk Factor for New Onset Diabetes in Patients with Coronary Artery Disease

Objective

To test the hypothesis that acute myocardial infarction (AMI) might accelerate development of new onset diabetes in patients with coronary artery disease independent of known risk factors.

Methods

We conducted a retrospective cohort study within COACT (CathOlic medical center percutAneous Coronary inTervention) registry. From a total of 9,127 subjects, 2,036 subjects were diabetes naïve and followed up for at least one year with both index and follow-up laboratory data about diabetes. Cox proportional hazard model was used to derive hazard ratios (HRs) and 95% confidence interval (CI) for new onset diabetes associated with AMI in univariate and multivariate analysis after adjusting several covariates.

Results

The overall hazard for diabetes was higher in AMI compared to non-AMI patients (p by log rank <0.01) with HR of 1.78 and 95% CI of 1.37–2.32 in univariate analysis. This association remained significant after adjusting covariates (HR, 1.54; 95% CI, 1.14–2.07; p<0.01). AMI was an independent predictor for higher quartile of WBC count in multivariate ordinal logistic regression analysis (OR, 6.75; 95% CI, 5.53–8.22, p<0.01). In subgroup analysis, the diabetogenic effect of AMI was more prominent in the subgroup without MetS compared to MetS patients (p for interaction<0.05). Compared to the reference group of non-AMI+nonMetS, the group of AMI+non-MetS (HR, 2.44; 95% CI, 1.58–3.76), non-AMI+MetS (HR, 3.42; 95% CI, 2.34–4.98) and AMI+MetS (HR, 4.12; 95% CI, 2.67–6.36) showed higher HR after adjusting covariates. However, the hazard was not different between the non-AMI+MetS and AMI+non-MetS groups.

Conclusions

AMI patients have a greater risk of new-onset diabetes when compared to non AMI patients, especially those with mild metabolic abnormalities.

Regulation and consequences of monocytosis

Monocytes are part of the vertebrate innate immune system. Blood monocytes are produced by bone marrow and splenic progenitors that derive from hematopoietic stem cells (HSCs). In cardiovascular disease, such as atherosclerosis and myocardial infarction, HSCs proliferate at higher levels that in turn increase production of hematopoietic cells, including monocytes. Once produced in hematopoietic niches, monocytes intravasate blood vessels, circulate, and migrate to sites of inflammation. Monocyte recruitment to atherosclerotic plaque and the ischemic heart depends on various chemokines, such as CCL2, CX3 CL1, and CCL5. Once in tissue, monocytes can differentiate into macrophages and dendritic cells. Macrophages are end effector cells that regulate the steady state and tissue healing, but they can also promote disease. At sites of inflammation, monocytes and macrophages produce inflammatory cytokines, which can exacerbate disease progression. Macrophages can also phagocytose tissue debris and produce pro-healing cytokines. Additionally, macrophages are antigen-presenting cells and can prime T cells. The tissue environment, including cytokines and types of inflammation, instructs macrophage specialization. Understanding monocytosis and its consequences in disease will reveal new therapeutic opportunities without compromising steady state functions.

Monocytes in myocardial infarction

Myocardial infarction (MI) is the leading cause of death in developed countries. Though timely revascularization of the ischemic myocardium and current standard therapy reduce acute mortality after MI, long-term morbidity and mortality remain high. During the first 1 to 2 weeks after MI, tissues in the infarcted myocardium undergo rapid turnover, including digestion of extracellular matrix and fibrosis. Post-MI repair is crucial to survival. Monocytes recruited to the infarcted myocardium remove debris and facilitate the repair process. However, exaggerated inflammation may also impede healing, as demonstrated by the association between elevated white blood cell count and in-hospital mortality after MI. Monocytes produced in the bone marrow and spleen enter the blood after MI and are recruited to the injured myocardium in 2 phases. The first phase is dominated by Ly-6c(high) monocytes and the second phase by Ly-6c(low) monocytes. Yet the number of Ly6C(low) monocytes recruited to the infarct is much lower, and Ly6C(high) monocytes can differentiate to Ly6C(low) macrophages in later healing stages. Understanding the signals regulating monocytosis after MI will help design new therapies to facilitate cardiac healing and limit heart failure.

Inhibiting macrophage proliferation suppresses atherosclerotic plaque inflammation

Inflammation drives atherosclerotic plaque progression and rupture, and is a compelling therapeutic target. Consequently, attenuating inflammation by reducing local macrophage accumulation is an appealing approach. This can potentially be accomplished by either blocking blood monocyte recruitment to the plaque or increasing macrophage apoptosis and emigration. Because macrophage proliferation was recently shown to dominate macrophage accumulation in advanced plaques, locally inhibiting macrophage proliferation may reduce plaque inflammation and produce long-term therapeutic benefits. To test this hypothesis, we used nanoparticle-based delivery of simvastatin to inhibit plaque macrophage proliferation in apolipoprotein E deficient mice (Apoe^-/- ) with advanced atherosclerotic plaques. This resulted in rapid reduction of plaque inflammation and favorable phenotype remodeling. We then combined this short-term nanoparticle intervention with an eight-week oral statin treatment, and this regimen rapidly reduced and continuously suppressed plaque inflammation. Our results demonstrate that pharmacologically inhibiting local macrophage proliferation can effectively treat inflammation in atherosclerosis.

Emerging strategies to prevent heart failure after myocardial infarction

Congestive heart failure (CHF) remains a significant cause of death and disability in industrialized countries. Projections show that the prevalence of CHF will increase 46% from 2012 to 2030, resulting in over eight million adults with CHF in the United States. While substantial advances have been achieved in the treatment of CHF over the past two decades, CHF rivals cancer as a cause of mortality. Strategies focused on prevention of CHF should be emphasized to meaningfully impact the projected increase in CHF. Irrespective of the type of CHF, either systolic or diastolic, coronary artery disease has supplanted hypertension as the most prevalent cause for congestive heart failure, with a high rate of mortality and future hospitalizations. Since coronary artery disease plays a central role in the development of CHF, approaches to treat coronary artery disease and identification of patients at risk for recurrent myocardial infarction (RMI) are approaches to prevent development of CHF.            Subjects who sustain recurrent MI represent a particularly high-risk group for development of CHF. Despite the evolution of therapy for MI from thrombolytic therapy to primary percutaneous coronary intervention (PCI), RMI occurs in ~ 10% of patients in the first year after first MI, and 3 years after their first MI. In this review I explore emerging approaches to prevent RMI including the rationale for recent trials of complete revascularization at the time of MI, newly emerging biomarkers that have additive predictive value for identifying patients with high risk of CHF and death when using existing biomarkers. Finally, the paradigm of hematopoietic stem cell mobilization in MI leading to monocyte expansion and acceleration of atherosclerosis is discussed as an emerging approach to identify patients at high risk of RMI, CHF, and death after MI.