Atherosclerosis and its attendant clinical complications, such as myocardial infarction, stroke, and peripheral artery disease, are the leading cause of morbidity and mortality in Western societies. ...In response to biochemical and biomechanical stimuli, atherosclerotic lesion formation occurs from the participation of a range of cell types, inflammatory mediators, and shear stress. Over the past decade, microRNAs (miRNAs) have emerged as evolutionarily conserved, noncoding small RNAs that serve as important regulators and fine-tuners of a range of pathophysiological cellular effects and molecular signaling pathways involved in atherosclerosis. Accumulating studies reveal the importance of miRNAs in regulating key signaling and lipid homeostasis pathways that alter the balance of atherosclerotic plaque progression and regression. In this review, we highlight current paradigms of miRNA-mediated effects in atherosclerosis progression and regression. We provide an update on the potential use of miRNAs diagnostically for detecting increasing severity of coronary disease and clinical events. Finally, we provide a perspective on therapeutic opportunities and challenges for miRNA delivery in the field.
Coronary artery disease (CAD) is one of the major cardiovascular diseases affecting the global human population. This disease has been proved to be the major cause of death in both the developed and ...developing countries. Lifestyle, environmental factors, and genetic factors pose as risk factors for the development of cardiovascular disease. The prevalence of risk factors among healthy individuals elucidates the probable occurrence of CAD in near future. Genome‐wide association studies have suggested the association of chromosome 9p21.3 in the premature onset of CAD. The risk factors of CAD include diabetes mellitus, hypertension, smoking, hyperlipidemia, obesity, homocystinuria, and psychosocial stress. The eradication and management of CAD has been established through extensive studies and trials. Antiplatelet agents, nitrates, β‐blockers, calcium antagonists, and ranolazine are some of the few therapeutic agents used for the relief of symptomatic angina associated with CAD.
Coronary artery disease (CAD) is one of the major cardiovascular diseases affecting the global human population. This disease has been proved to be the major cause of death in both the developed and developing countries. Lifestyle, environmental factors, and genetic factors pose as risk factors for the development of cardiovascular disease. The prevalence of risk factors among healthy individuals elucidates the probable occurrence of CAD in near future. Genome‐wide association studies have suggested the association of chromosome 9p21.3 in the premature onset of CAD. The risk factors of CAD include diabetes mellitus, hypertension, smoking, hyperlipidemia, obesity, homocystinuria, and psychosocial stress. The eradication and management of CAD has been established through extensive studies and trials. Antiplatelet agents, nitrates, β‐blockers, calcium antagonists, and ranolazine are some of the few therapeutic agents used for the relief of symptomatic angina associated with CAD.
The Synergy between PCI with Taxus and Cardiac Surgery (SYNTAX) trial was a non-inferiority trial that compared percutaneous coronary intervention (PCI) using first-generation paclitaxel-eluting ...stents with coronary artery bypass grafting (CABG) in patients with de-novo three-vessel and left main coronary artery disease, and reported results up to 5 years. We now report 10-year all-cause death results.
The SYNTAX Extended Survival (SYNTAXES) study is an investigator-driven extension of follow-up of a multicentre, randomised controlled trial done in 85 hospitals across 18 North American and European countries. Patients with de-novo three-vessel and left main coronary artery disease were randomly assigned (1:1) to the PCI group or CABG group. Patients with a history of PCI or CABG, acute myocardial infarction, or an indication for concomitant cardiac surgery were excluded. The primary endpoint of the SYNTAXES study was 10-year all-cause death, which was assessed according to the intention-to-treat principle. Prespecified subgroup analyses were performed according to the presence or absence of left main coronary artery disease and diabetes, and according to coronary complexity defined by core laboratory SYNTAX score tertiles. This study is registered with ClinicalTrials.gov, NCT03417050.
From March, 2005, to April, 2007, 1800 patients were randomly assigned to the PCI (n=903) or CABG (n=897) group. Vital status information at 10 years was complete for 841 (93%) patients in the PCI group and 848 (95%) patients in the CABG group. At 10 years, 248 (28%) patients had died after PCI and 212 (24%) after CABG (hazard ratio 1·19 95% CI 0·99–1·43, p=0·066). Among patients with three-vessel disease, 153 (28%) of 546 had died after PCI versus 114 (21%) of 549 after CABG (hazard ratio 1·42 95% CI 1·11–1·81), and among patients with left main coronary artery disease, 95 (27%) of 357 had died after PCI versus 98 (28%) of 348 after CABG (0·92 0·69–1·22, pinteraction=0·023). There was no treatment-by-subgroup interaction with diabetes (pinteraction=0·60) and no linear trend across SYNTAX score tertiles (ptrend=0·20).
At 10 years, no significant difference existed in all-cause death between PCI using first-generation paclitaxel-eluting stents and CABG. However, CABG provided a significant survival benefit in patients with three-vessel disease, but not in patients with left main coronary artery disease.
German Foundation of Heart Research (SYNTAXES study, 5–10-year follow-up) and Boston Scientific Corporation (SYNTAX study, 0–5-year follow-up).
Abstract
In this review, we summarize current knowledge on the genetics of coronary artery disease, based on 10 years of genome-wide association studies. The discoveries began with individual studies ...using 200K single nucleotide polymorphism arrays and progressed to large-scale collaborative efforts, involving more than a 100 000 people and up to 40 Mio genetic variants. We discuss the challenges ahead, including those involved in identifying causal genes and deciphering the links between risk variants and disease pathology. We also describe novel insights into disease biology based on the findings of genome-wide association studies. Moreover, we discuss the potential for discovery of novel treatment targets through the integration of different layers of 'omics' data and the application of systems genetics approaches. Finally, we provide a brief outlook on the potential for precision medicine to be enhanced by genome-wide association study findings in the cardiovascular field.
Genetic factors contribute importantly to the risk of coronary artery disease (CAD), and in the past decade, there has been major progress in this area. The tools applied include genome-wide ...association studies encompassing >200 000 individuals complemented by bioinformatic approaches, including 1000 Genomes imputation, expression quantitative trait locus analyses, and interrogation of Encyclopedia of DNA Elements, Roadmap, and other data sets. close to 60 common SNPs (minor allele frequency>0.05) associated with CAD risk and reaching genome-wide significance (P<5×10) have been identified. Furthermore, a total of 202 independent signals in 109 loci have achieved a false discovery rate (q<0.05) and together explain 28% of the estimated heritability of CAD. These data have been used successfully to create genetic risk scores that can improve risk prediction beyond conventional risk factors and identify those individuals who will benefit most from statin therapy. Such information also has important applications in clinical medicine and drug discovery by using a Mendelian randomization approach to interrogate the causal nature of many factors found to associate with CAD risk in epidemiological studies. In contrast to genome-wide association studies, whole-exome sequencing has provided valuable information directly relevant to genes with known roles in plasma lipoprotein metabolism but has, thus far, failed to identify other rare coding variants linked to CAD. Overall, recent studies have led to a broader understanding of the genetic architecture of CAD and demonstrate that it largely derives from the cumulative effect of multiple common risk alleles individually of small effect size rather than rare variants with large effects on CAD risk. Despite this success, there has been limited progress in understanding the function of the novel loci; the majority of which are in noncoding regions of the genome.
Recognition of ischemic heart disease (IHD) is often delayed or deferred in women. Thus, many at risk for adverse outcomes are not provided specific diagnostic, preventive, and/or treatment ...strategies. This lack of recognition is related to sex-specific IHD pathophysiology that differs from traditional models using data from men with flow-limiting coronary artery disease (CAD) obstructions. Symptomatic women are less likely to have obstructive CAD than men with similar symptoms, and tend to have coronary microvascular dysfunction, plaque erosion, and thrombus formation. Emerging data document that more extensive, nonobstructive CAD involvement, hypertension, and diabetes are associated with major adverse events similar to those with obstructive CAD. A central emerging paradigm is the concept of nonobstructive CAD as a cause of IHD and related adverse outcomes among women. This position paper summarizes currently available knowledge and gaps in that knowledge, and recommends management options that could be useful until additional evidence emerges.
Myocardial infarction in the absence of obstructive coronary artery disease is found in ≈5% to 6% of all patients with acute infarction who are referred for coronary angiography. There are a variety ...of causes that can result in this clinical condition. As such, it is important that patients are appropriately diagnosed and an evaluation to uncover the correct cause is performed so that, when possible, specific therapies to treat the underlying cause can be prescribed. This statement provides a formal and updated definition for the broadly labelled term MINOCA (incorporating the definition of acute myocardial infarction from the newly released “Fourth Universal Definition of Myocardial Infarction”) and provides a clinically useful framework and algorithms for the diagnostic evaluation and management of patients with myocardial infarction in the absence of obstructive coronary artery disease.
Coronary artery calcification is a well-established predictor of future cardiac events; however, it is not a predictor of unstable plaque. The intimal calcification of the atherosclerotic plaques may ...begin with smooth muscle cell apoptosis and release of matrix vesicles and is almost always seen microscopically in pathological intimal thickening, which appears as microcalcification (≥0.5 μm, typically <15 μm in diameter). Calcification increases with macrophage infiltration into the lipid pool in early fibroatheroma where they undergo apoptosis and release matrix vesicles. The confluence of calcified areas involves extracellular matrix and the necrotic core, which can be identified by radiography as speckled (≤2 mm) or fragmented (>2, <5 mm) calcification. The calcification in thin-cap fibroatheromas and plaque rupture is generally less than what is observed in stable plaques and is usually speckled or fragmented. Fragmented calcification spreads into the surrounding collagen-rich matrix forming calcified sheets, the hallmarks of fibrocalcific plaques. The calcified sheets may break into nodules with fibrin deposition, and when accompanied by luminal protrusion, it is associated with thrombosis. Calcification is highest in fibrocalcific plaques followed by healed plaque rupture and is the least in erosion and pathological intimal thickening. The extent of calcification is greater in men than in women especially in the premenopausal period and is also greater in whites compared with blacks. The mechanisms of intimal calcification remain poorly understood in humans. Calcification often occurs in the presence of apoptosis of smooth muscle cells and macrophages with matrix vesicles accompanied by expression of osteogenic markers within the vessel wall.
BACKGROUND:Current guidelines call for high-intensity statin therapy in patients with cardiovascular disease on the basis of several previous “more versus less statins” trials. However, no clear ...evidence for more versus less statins has been established in an Asian population.
METHODS:In this prospective, multicenter, randomized, open-label, blinded end point study, 13 054 Japanese patients with stable coronary artery disease who achieved low-density lipoprotein cholesterol (LDL-C) <120 mg/dL during a run-in period (pitavastatin 1 mg/d) were randomized in a 1-to-1 fashion to high-dose (pitavastatin 4 mg/d; n=6526) or low-dose (pitavastatin 1 mg/d; n=6528) statin therapy. The primary end point was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal ischemic stroke, or unstable angina requiring emergency hospitalization. The secondary composite end point was a composite of the primary end point and clinically indicated coronary revascularization excluding target-lesion revascularization at sites of prior percutaneous coronary intervention.
RESULTS:The mean age of the study population was 68 years, and 83% were male. The mean LDL-C level before enrollment was 93 mg/dL with 91% of patients taking statins. The baseline LDL-C level after the run-in period on pitavastatin 1 mg/d was 87.7 and 88.1 mg/dL in the high-dose and low-dose groups, respectively. During the entire course of follow-up, LDL-C in the high-dose group was lower by 14.7 mg/dL than in the low-dose group (P<0.001). With a median follow-up of 3.9 years, high-dose as compared with low-dose pitavastatin significantly reduced the risk of the primary end point (266 patients 4.3% and 334 patients 5.4%; hazard ratio, 0.81; 95% confidence interval, 0.69–0.95; P=0.01) and the risk of the secondary composite end point (489 patients 7.9% and 600 patients 9.7%; hazard ratio, 0.83; 95% confidence interval, 0.73–0.93; P=0.002). High-dose pitavastatin also significantly reduced the risks of several other secondary end points such as all-cause death, myocardial infarction, and clinically indicated coronary revascularization. The results for the primary and the secondary composite end points were consistent across several prespecified subgroups, including the low (<95 mg/dL) baseline LDL-C subgroup. Serious adverse event rates were low in both groups.
CONCLUSIONS:High-dose (4 mg/d) compared with low-dose (1 mg/d) pitavastatin therapy significantly reduced cardiovascular events in Japanese patients with stable coronary artery disease.
CLINICAL TRIAL REGISTRATION:URLhttps://www.clinicaltrials.gov. Unique identifierNCT01042730.
Macrophages play a central role in the development of atherosclerotic cardiovascular disease (ASCVD), which encompasses coronary artery disease, peripheral artery disease, cerebrovascular disease, ...and aortic atherosclerosis. In each vascular bed, macrophages contribute to the maintenance of the local inflammatory response, propagate plaque development, and promote thrombosis. These central roles, coupled with their plasticity, makes macrophages attractive therapeutic targets in stemming the development of and stabilizing existing atherosclerosis. In the context of ASCVD, classically activated M1 macrophages initiate and sustain inflammation, and alternatively activated M2 macrophages resolve inflammation. However, this classification is now considered an oversimplification, and a greater understanding of plaque macrophage physiology in ASCVD is required to aid in the development of therapeutics to promote ASCVD regression. Reviewed herein are the macrophage phenotypes and molecular regulators characteristic of ASCVD regression, and the current murine models of ASCVD regression.
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