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BACKGROUND AND AIMS: Microstructural disturbances underlie dysfunctional contraction and adverse left ventricular (LV) remodelling after ST-elevation myocardial infarction (STEMI). Biphasic diffusion tensor cardiovascular magnetic resonance (DT-CMR) quantifies dynamic reorientation of sheetlets (E2A) from diastole to systole during myocardial thickening, and markers of tissue integrity [mean diffusivity (MD) and fractional anisotropy (FA)]. This study investigated whether microstructural alterations identified by biphasic DT-CMR: (i) enable contrast-free detection of acute myocardial infarction (MI); (ii) associate with severity of myocardial injury and contractile dysfunction; and (iii) predict adverse LV remodelling. METHODS: Biphasic DT-CMR was acquired 4 days (n = 70) and 4 months (n = 66) after reperfused STEMI and in healthy volunteers (HVOLs) (n = 22). Adverse LV remodelling was defined as an increase in LV end-diastolic volume ≥ 20% at 4 months. MD and FA maps were compared with late gadolinium enhancement images. RESULTS: Widespread microstructural disturbances were detected post-STEMI. In the acute MI zone, diastolic E2A was raised and systolic E2A reduced, resulting in reduced E2A mobility (all P < .001 vs. adjacent and remote zones and HVOLs). Acute global E2A mobility was the only independent predictor of adverse LV remodelling (odds ratio .77; 95% confidence interval .63-.94; P = .010). MD and FA maps had excellent sensitivity and specificity (all > 90%) and interobserver agreement for detecting MI presence and location. CONCLUSIONS: Biphasic DT-CMR identifies microstructural alterations in both diastole and systole after STEMI, enabling detection of MI presence and location as well as predicting adverse LV remodelling. DT-CMR has potential to provide a single contrast-free modality for MI detection and prognostication of patients after acute STEMI.
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BACKGROUND: Adverse left ventricular (LV) remodelling after myocardial infarction is associated with heart failure. We investigated whether aortic stiffness during acute ST-segment elevation myocardial infarction is associated with LV remodelling at long-term follow-up. METHODS: In 109 patients within 48 h of myocardial infarction post-primary percutaneous coronary intervention and after 2 years, we measured: (a) carotid to femoral pulse wave velocity (PWV), (b) LV global longitudinal strain (GLS) and left atrial strain using speckle-tracking echocardiography, (c) PWV/GLS ratio as a surrogate marker of ventricular-arterial interaction, and (d) LV end-diastolic and end-systolic volumes. A > 15% decrease from the baseline in LV end-systolic volume at 2-year follow-up was considered as a criterion of reverse LV remodelling. RESULTS: Compared with baseline, all patients had reduced PWV, LV end-diastolic and end-systolic volumes while PWV/GLS, GLS and reservoir left atrial strain were improved (p < .05) after 2 years. Baseline values of PWV, GLS, PWV/GLS ratio and reservoir left atrial strain were associated with percentage change of LV end-systolic volume at 2 years (p < .05). Multivariable analysis revealed that lower baseline values of PWV and a less impaired GLS and PWV/GLS were independently associated with reverse LV remodelling at 2 years with a C-statistic of .748, .711 and .787, respectively. CONCLUSION: Aortic stiffness early post-infarction determines LV remodelling after 2 years of the ischemic event despite post successful revascularization. CLINICAL TRIAL REGISTRATION-URL: http://www. CLINICALTRIALS: gov. Unique identifier: NCT03984123, 30/04/2020.
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Infarto do Miocárdio , Rigidez Vascular , Disfunção Ventricular Esquerda , Humanos , Função Ventricular Esquerda , Remodelação Ventricular , Análise de Onda de Pulso , Infarto do Miocárdio/complicações , Disfunção Ventricular Esquerda/complicações , Volume SistólicoRESUMO
Heart failure represents a dynamic clinical challenge with the continuous rise of a multi-morbid and ageing population. Yet, the evolving nature of mechanical circulatory support offers a variety of means to manage candidates who might benefit from such interventions. This narrative review focuses on the role of the main mechanical circulatory support devices, such as ventricular assist device, extracorporeal membrane oxygenation, Impella and TandemHeart, in the physiological process of ventricular unloading and remodelling in heart failure, highlighting their characteristics, mechanism and clinical outcomes. The outcome measures described include physiological changes (i.e., stroke volume or preload and afterload), intracardiac pressure (i.e., end-diastolic pressure) and extracardiac pressure (i.e., pulmonary capillary wedge pressure). Overall, all the above mechanical circulatory support strategies can facilitate the unloading of the ventricular failure through different mechanisms, which subsequently affects the ventricular remodelling process. These physiological changes start immediately after ventricular assist device implantation. The devices are indicated in different but overlapping populations and operate in distinctive ways; yet, they have evidenced performance to a favourable standard to improve cardiac function in heart failure, although this proved variable for different devices, and further high-quality trials are vital to assess their clinical outcomes further. Both Impella and TandemHeart are indicated mainly in cardiogenic shock and high-risk percutaneous coronary intervention patients; at the time the literature was evaluated, both devices were found to yield a significant improvement in haemodynamics but not in survival. Nevertheless, the choice of device strategy should be based on individual patient factors, including indication, to optimize clinical outcomes.
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Insuficiência Cardíaca , Coração Auxiliar , Remodelação Ventricular , Humanos , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Remodelação Ventricular/fisiologia , Oxigenação por Membrana Extracorpórea/métodos , Função Ventricular Esquerda/fisiologia , Ventrículos do Coração/fisiopatologiaRESUMO
Sustained pressure overload and fibrosis of the right ventricle (RV) are the leading causes of mortality in pulmonary arterial hypertension (PAH). Although the role of adenosine in PAH has been attributed to the control of pulmonary vascular tone, cardiac reserve, and inflammatory processes, the involvement of the nucleoside in RV remodelling remains poorly understood. Conflicting results exist on targeting the low-affinity adenosine A2B receptor (A2BAR) for the treatment of PAH mostly because it displays dual roles in acute vs. chronic lung diseases. Herein, we investigated the role of the A2BAR in the viability/proliferation and collagen production by cardiac fibroblasts (CFs) isolated from RVs of rats with monocrotaline (MCT)-induced PAH. CFs from MCT-treated rats display higher cell viability/proliferation capacity and overexpress A2BAR compared to the cells from healthy littermates. The enzymatically stable adenosine analogue, 5'-N-ethylcarboxamidoadenosine (NECA, 1-30 µM), concentration-dependently increased growth, and type I collagen production by CFs originated from control and PAH rats, but its effects were more prominent in cells from rats with PAH. Blockage of the A2BAR with PSB603 (100 nM), but not of the A2AAR with SCH442416 (100 nM), attenuated the proliferative effect of NECA in CFs from PAH rats. The A2AAR agonist, CGS21680 (3 and 10 nM), was virtually devoid of effect. Overall, data suggest that adenosine signalling via A2BAR may contribute to RV overgrowth secondary to PAH. Therefore, blockage of the A2AAR may be a valuable therapeutic alternative to mitigate cardiac remodelling and prevent right heart failure in PAH patients.
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Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Animais , Humanos , Ratos , Adenosina-5'-(N-etilcarboxamida) , Modelos Animais de Doenças , Fibroblastos/metabolismo , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/metabolismo , Receptor A2B de Adenosina/metabolismoRESUMO
BACKGROUND: Type-D personality is an established predisposing factor for various diseases. Type-D traits have been shown to pose a 26% increased risk of coronary artery disease after controlling for other confounding factors. Significant associations have been reported between type-D personality traits and dyslipidaemia, impaired endothelial function, coronary heart disease (CAD), acute myocardial infarction, and other adverse cardiovascular events. OBJECTIVE: To assess the association between type-D personality and left-ventricular adverse remodelling in patients treated with percutaneous coronary intervention following index ST-segment elevation myocardial infarction. METHODS: All patients hospitalized and treated with percutaneous coronary intervention (PCI) after their index ST-segment elevation myocardial infarction (STEMI) between 1 January 2022 to 31 December 2023 were prospectively enrolled. Type-D personality traits in the study population were determined at baseline using type-D Scale-14 (DS14) instrument, whereas any positive change in left ventricular end diastolic volume (LVEDV) ≥ 20% at follow up period of 12-months from baseline was defined as left-ventricular adverse remodelling (LVAR). Univariate and multivariate analysis was done to establish the independent predictors of LVAR. The area under receiver-operating characteristic curve (AUROC) was employed to assess the sensitivity and specificity of the identified independent predictors. RESULTS: A total of 124 patients were enrolled in the study. The mean age of the study population was 67 ± 10 years and the overall incidence of LVAR was found to be 25%. Multivariate regression analysis revealed that type-D personality is a significant independent predictor of LVAR [Formula: see text] apart from the already established independent predictors Killip Class[Formula: see text], baseline Global Longitudinal strain (GLS)[Formula: see text], and 3-vessel CAD[Formula: see text]. In ROC curve analysis type-D personality as an independent predictor of LVAR achieved a sensitivity of 41.4% and a specificity of 87.1%, p < 0.02. CONCLUSION: Type-D personality trait is a significant independent predictor of LVAR in patients treated with PCI after their index-STEMI.
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Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Personalidade Tipo D , Função Ventricular Esquerda , Remodelação Ventricular , Humanos , Masculino , Intervenção Coronária Percutânea/efeitos adversos , Feminino , Pessoa de Meia-Idade , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Estudos Prospectivos , Idoso , Resultado do Tratamento , Fatores de Risco , Fatores de Tempo , Medição de RiscoRESUMO
In this research, we aimed to observe the changes in myocardial fibrosis indices in patients with chronic heart failure before and after treatment and to evaluate the anti-chronic heart failure and ventricular remodelling effects of Trichosanthis peel (TP) injection. This study was a single-center, open, single-blind, randomized controlled study with an optimal efficacy design. Patients were consecutively and randomly divided into two groups, with 36 patients in the TP injection group and 36 patients in the conventional treatment group. ELISA was used to measure changes in myocardial fibrosis indices before and after discharge, including transforming growth factor ß (TGF-ß), serum hyaluronic acid (HA), type I procollagen (PCI), laminin (LN) and type III procollagen (PCIII). There was no significant difference between the two groups in clinical data or baseline level of myocardial fibrosis before treatment. After treatment, compared with the conventional treatment group, the myocardial fibrosis index was significantly decreased following TP injection. Our findings indicate that TP injection combined with conventional medicine can attenuate myocardial fibrosis by reducing angiotensin II, aldosterone, TGFß, HA, PCI, metallomatrix proteinase 2, connective tissue growth factor and LN and promote ventricular remodelling in patients with chronic heart failure.
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Líquidos Corporais , Insuficiência Cardíaca , Humanos , Método Simples-Cego , Remodelação Ventricular , Insuficiência Cardíaca/tratamento farmacológico , Angiotensina II , Doença CrônicaRESUMO
BACKGROUND: Rheumatic heart disease (RHD) is the most common form of acquired heart disease worldwide. In RHD, volume loading from mitral regurgitation leads to left ventricular (LV) dilatation, increased wall stress, and ultimately LV dysfunction. Improved understanding of LV dynamics may contribute to refined timing of intervention. We aimed to characterize and compare left ventricular remodelling between rheumatic heart disease (RHD) severity groups by way of serial echocardiographic assessment of volumes and function in children. METHODS: Children with RHD referred to Perth Children's Hospital (formally Princess Margaret Hospital) (1987-2020) were reviewed. Patients with longitudinal pre-operative echocardiograms at diagnosis, approximately 12 months and at most recent follow-up, were included and stratified into RHD severity groups. Left ventricular (LV) echocardiographic parameters were assessed. Adjusted linear mixed effect models were used to compare interval changes. RESULTS: 146 patients (median age 10 years, IQR 6-14 years) with available longitudinal echocardiograms were analysed. Eighty-five (58.2%) patients had mild, 33 (22.6%) moderate and 28 (19.2%) severe RHD at diagnosis. Mean duration of follow-up was 4.6 years from the initial diagnosis. Severe RHD patients had significantly increased end-systolic volumes (ESV) and end-diastolic volumes (EDV) compared to mild/moderate groups at diagnosis (severe versus mild EDV mean difference 27.05 ml/m2, p < 0.001, severe versus moderate EDV mean difference 14.95 ml/m2, p = 0.006). Mild and moderate groups experienced no significant progression of changes in volume measures. In severe RHD, LV dilatation worsened over time. All groups had preserved cardiac function. CONCLUSIONS: In mild and moderate RHD, the lack of progression of valvular regurgitation and ventricular dimensions suggest a stable longer-term course. Significant LV remodelling occurred at baseline in severe RHD with progression of LV dilatation over time. LV function was preserved across all groups. Our findings may guide clinicians in deciding the frequency and timing of follow-up and may be of clinical utility during further reiterations of the Australia and New Zealand RHD Guidelines.
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Insuficiência da Valva Mitral , Cardiopatia Reumática , Criança , Humanos , Cardiopatia Reumática/diagnóstico por imagem , Seguimentos , Remodelação Ventricular , Coração , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/etiologiaRESUMO
Right ventricular (RV) pressure loading leads to RV and left ventricular (LV) dysfunction through RV hypertrophy, dilatation and fibrosis. Relief of RV pressure load improves RV function. However, the impact and mechanisms on biventricular reverse-remodelling and function are only partially characterized. We evaluated the impact of RV pressure overload relief on biventricular remodelling and function in a rabbit model of reversible pulmonary artery banding (PAB). Rabbits were randomized to three groups: (1) Sham-operated controls (n = 7); (2) PAB (NDef, n = 7); (3) PAB followed by band deflation (Def, n = 5). Sham and NDef animals were sacrificed at 6 weeks after PAB surgery. Def animals underwent PAB deflation at 6 weeks and sacrifice at 9 weeks. Biventricular geometry, function, haemodynamics, hypertrophy and fibrosis were compared between groups using echocardiography, magnetic resonance imaging, high-fidelity pressure-tipped catheters and histology. RV pressure loading caused RV dilatation, systolic dysfunction, myocyte hypertrophy and LV compression which improved after PAB deflation. RV end-diastolic pressure (RVEDP) decreased after PAB deflation, although remaining elevated vs. Sham. LV end-diastolic pressure (LVEDP) was unchanged following PAB deflation. RV and LV collagen volumes in the NDef and Def group were increased vs. Sham, whereas RV and LV collagen volumes were similar between NDef and Def groups. RV myocyte hypertrophy (r = 0.75, P < 0.001) but not collagen volume was related to RVEDP. LV myocyte hypertrophy (r = 0.58, P = 0.016) and collagen volume (r = 0.56, P = 0.031) correlated with LVEDP. In conclusion, relief of RV pressure overload improves RV and LV geometry, hypertrophy and function independent of fibrosis. The long-term implications of persistent fibrosis and increased biventricular filling pressures, even after pressure load relief, need further study. KEY POINTS: Right ventricular (RV) pressure loading in a pulmonary artery banding rabbit model is associated with RV dilatation, left ventricular (LV) compression; biventricular myocyte hypertrophy, fibrosis and dysfunction. The mechanisms and impact of RV pressure load relief on biventricular remodelling and function has not been extensively studied. Relief of RV pressure overload improves biventricular geometry in conjunction with improved RV myocyte hypertrophy and function independent of reduced fibrosis. These findings raise questions as to the importance of fibrosis as a therapeutic target.
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Disfunção Ventricular Esquerda , Disfunção Ventricular Direita , Animais , Modelos Animais de Doenças , Fibrose , Ventrículos do Coração , Hipertrofia , Artéria Pulmonar , Coelhos , Disfunção Ventricular Esquerda/complicações , Função Ventricular Direita , Pressão VentricularRESUMO
An increase in left ventricular volumes between baseline and follow-up imaging is the main criteria for the quantification of left ventricular remodelling (LVR) after ST-elevation myocardial infarction (STEMI), but without consensual definition. We aimed to review the criteria used for the definition of LVR based on cardiac magnetic resonance imaging (CMR) in STEMI patients. A systematic literature search was conducted using MEDLINE and the Cochrane Library from January 2010 to August 2019. Thirty-seven studies involving 4209 patients were included. Among these studies, 30 (81%) used a cut-off value for defining LVR, with a pooled LVR prevalence estimate of 22.8%, 95% CI [19.4-26.7%] and a major between-study heterogeneity (I2 = 82%). The seven remaining studies (19%) defined LVR as a continuous variable. The definition of LVR using CMR following STEMI is highly variable, among studies including highly selected patients. A 20% increase or a 15% increase in left ventricular volumes between a baseline and a follow-up CMR imaging were the two most common criterion (13 [35%] and 9 [24%] studies, respectively). The most frequent LVR criterion was a 20% increase in end-diastolic volumes or a 15% increase in end-systolic volumes. A composite cut-off value of a 12 to 15% increase in end-systolic volume and a 12 to 20% increase in end-diastolic volume using a follow-up CMR imaging 3 months after STEMI might be proposed as a consensual cut-off for defining adverse LVR for future large-sized, prospective studies with serial CMR imaging and long-term follow-up in unselected patients.
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Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Imageamento por Ressonância Magnética , Imagem Cinética por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Estudos Prospectivos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Função Ventricular Esquerda , Remodelação VentricularRESUMO
Diabetes mellitus predisposes affected individuals to a significant spectrum of cardiovascular complications, one of the most debilitating in terms of prognosis is heart failure. Indeed, the increasing global prevalence of diabetes mellitus and an aging population has given rise to an epidemic of diabetes mellitus-induced heart failure. Despite the significant research attention this phenomenon, termed diabetic cardiomyopathy, has received over several decades, understanding of the full spectrum of potential contributing mechanisms, and their relative contribution to this heart failure phenotype in the specific context of diabetes mellitus, has not yet been fully resolved. Key recent preclinical discoveries that comprise the current state-of-the-art understanding of the basic mechanisms of the complex phenotype, that is, the diabetic heart, form the basis of this review. Abnormalities in each of cardiac metabolism, physiological and pathophysiological signaling, and the mitochondrial compartment, in addition to oxidative stress, inflammation, myocardial cell death pathways, and neurohumoral mechanisms, are addressed. Further, the interactions between each of these contributing mechanisms and how they align to the functional, morphological, and structural impairments that characterize the diabetic heart are considered in light of the clinical context: from the disease burden, its current management in the clinic, and where the knowledge gaps remain. The need for continued interrogation of these mechanisms (both known and those yet to be identified) is essential to not only decipher the how and why of diabetes mellitus-induced heart failure but also to facilitate improved inroads into the clinical management of this pervasive clinical challenge.
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Cardiomiopatias Diabéticas/patologia , Animais , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/terapia , Coração/fisiopatologia , Humanos , Miocárdio/patologiaRESUMO
Accumulating evidence suggests that supplementation of n-3 PUFA was associated with reduction in risk of major cardiovascular events. This meta-analysis was to systematically evaluate whether daily supplementation and accumulated intake of n-3 PUFA are associated with improved left ventricular (LV) remodelling in patients with chronic heart failure (CHF). Articles were obtained from Pubmed, Clinical key and Web of Science from inception to January 1 in 2021, and a total of twelve trials involving 2162 participants were eligible for inclusion. The sources of study heterogeneity were explained by I2 statistic and subgroup analysis. Compared with placebo groups, n-3 PUFA supplementation improved LV ejection fraction (LVEF) (eleven trials, 2112 participants, weighted mean difference (WMD) = 2·52, 95 % CI 1·25, 3·80, I2 = 87·8 %) and decreased LV end systolic volume (five studies, 905 participants, WMD = -3·22, 95 % CI 3·67, -2·77, I2 = 0·0 %) using the continuous variables analysis. Notably, the high accumulated n-3 PUFA dosage groups (≥ 600 g) presented a prominent improvement in LVEF, while the low and middle accumulated dosage (≤ 300 and 300-600 g) showed no effects on LVEF. In addition, n-3 PUFA supplementation decreased the levels of pro-inflammatory mediators including TNF-α, IL-6 (IL-6) and hypersensitive c-reactive protein. Therefore, the present meta-analysis demonstrated that n-3 PUFA consumption was associated with a substantial improvement of LV function and remodelling in patients subjected to CHF. The accumulated dosage of n-3 PUFA intake is vital for its cardiac protective role.
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Phosphorylcholine is a pro-inflammatory epitope exposed on apoptotic cells, and phosphorylcholine monoclonal immunoglobulin (Ig)G antibodies (PC-mAb) have anti-inflammatory properties. In this study, we hypothesize that PC-mAb treatment reduces adverse cardiac remodelling and infarct size (IS) following unreperfused transmural myocardial infarction (MI). Unreperfused MI was induced by permanent ligation of the left anterior descending (LAD) coronary artery in hypercholesterolaemic APOE*3-Leiden mice. Three weeks following MI, cardiac magnetic resonance (CMR) imaging showed a reduced LV end-diastolic volume (EDV) by 21% and IS by 31% upon PC-mAb treatment as compared to the vehicle control group. In addition, the LV fibrous content was decreased by 27% and LV wall thickness was better preserved by 47% as determined by histological analysis. Two days following MI, CCL2 concentrations, assessed by use of ELISA, were decreased by 81% and circulating monocytes by 64% as assessed by use of FACS analysis. Additionally, local leucocyte infiltration determined by immunohistological analysis showed a 62% decrease after three weeks. In conclusion, the local and systemic inflammatory responses are limited by PC-mAb treatment resulting in restricted adverse cardiac remodelling and IS following unreperfused MI. This indicates that PC-mAb holds promise as a therapeutic agent following MI limiting adverse cardiac remodelling.
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Anticorpos Monoclonais/farmacologia , Inflamação/tratamento farmacológico , Isquemia/complicações , Infarto do Miocárdio/prevenção & controle , Fosforilcolina/imunologia , Remodelação Ventricular/efeitos dos fármacos , Animais , Apolipoproteína E3/genética , Apolipoproteína E3/metabolismo , Modelos Animais de Doenças , Feminino , Inflamação/metabolismo , Inflamação/patologia , Camundongos , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologiaRESUMO
The aim of this study is to evaluate whether the alterations in glucose metabolism and insulin resistance are mechanisms presented in cardiac remodelling induced by the toxicity of cigarette smoke. Male Wistar rats were assigned to the control group (C; n = 12) and the cigarette smoke-exposed group (exposed to cigarette smoke over 2 months) (CS; n = 12). Transthoracic echocardiography, blood pressure assessment, serum biochemical analyses for catecholamines and cotinine, energy metabolism enzymes activities assay; HOMA index (homeostatic model assessment); immunohistochemistry; and Western blot for proteins involved in energy metabolism were performed. The CS group presented concentric hypertrophy, systolic and diastolic dysfunction, and higher oxidative stress. It was observed changes in energy metabolism, characterized by a higher HOMA index, lower concentration of GLUT4 (glucose transporter 4) and lower 3-hydroxyl-CoA dehydrogenase activity, suggesting the presence of insulin resistance. Yet, the cardiac glycogen was depleted, phosphofructokinase (PFK) and lactate dehydrogenase (LDH) increased, with normal pyruvate dehydrogenase (PDH) activity. The activity of citrate synthase, mitochondrial complexes and ATP synthase (adenosine triphosphate synthase) decreased and the expression of Sirtuin 1 (SIRT1) increased. In conclusion, exposure to cigarette smoke induces cardiac remodelling and dysfunction. The mitochondrial dysfunction and heart damage induced by cigarette smoke exposure are associated with insulin resistance and glucose metabolism changes.
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Glucose/metabolismo , Resistência à Insulina , Fumar/efeitos adversos , Remodelação Ventricular , Animais , Catecolaminas/sangue , Cotinina/sangue , Eletrocardiografia , Metabolismo Energético , Masculino , Estresse Oxidativo , Ratos WistarRESUMO
Heart failure (HF) continues to be a serious public health challenge despite significant advancements in therapeutics and is often complicated by multiple other comorbidities. Of particular concern is type 2 diabetes mellitus (T2DM) which not only amplifies the risk, but also limits the treatment options available to patients. The sodium-glucose linked cotransporter subtype 2 (SGLT2)-inhibitor class, which was initially developed as a treatment for T2DM, has shown great promise in reducing cardiovascular risk, particularly around HF outcomes - regardless of diabetes status.There are ongoing efforts to elucidate the true mechanism of action of this novel drug class. Its primary mechanism of inducing glycosuria and diuresis from receptor blockade in the renal nephron seems unlikely to be responsible for the rapid and striking benefits seen in clinical trials. Early mechanistic work around conventional therapeutic targets seem to be inconclusive. There are some emerging theories around its effect on myocardial energetics and calcium balance as well as on renal physiology. In this review, we discuss some of the cutting-edge hypotheses and concepts currently being explored around this drug class in an attempt better understand the molecular mechanics of this novel agent.
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Diabetes Mellitus Tipo 2 , Glicosúria , Inibidores do Transportador 2 de Sódio-Glicose , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diurese , Humanos , Transportador 2 de Glucose-Sódio , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêuticoRESUMO
BACKGROUND: The beneficial effects of physical exercise on cardiac remodelling improvement after myocardial infarction have already been suggested. However, the results of previous clinical trials have not been consistent. Moreover, the putative molecular mechanisms leading to the clinically observed effects of physical exercise still remain elusive. AIM: We aimed to evaluate whether the well-defined and strictly controlled traditional Chinese Qigong Baduanjin exercise (BE) would attenuate the adverse left ventricular (LV) remodelling in patients with ST-elevation myocardial infarction (STEMI). METHODS: A total of 110 clinically stable STEMI patients, following successful revascularization of their infarcted coronary arteries, were randomized and enrolled in two groups: 56 were subjected to a 12-week BE-based cardiac rehabilitation programme (BE group), and the remaining 54 were exposed to the usual physical exercise (control group) for the same time period. The primary outcome was the change from baseline to 6 months in the echocardiographic LV end-diastolic volume index (ΔLVEDVi). Proteomic analysis was also performed to uncover associated mechanisms. RESULTS: Compared with the control group, the BE group showed significantly lower ΔLVEDVi (-5.1 ± 1.1 vs. 0.3 ± 1.2 mL/m2, P < 0.01). Proteomic analysis revealed BE-induced variations in the expression of 80 proteins linked to regulation the of metabolic process, immune process, and extracellular matrix reorganization. Furthermore, correlation analyses between the validated serum proteomes and primary endpoint demonstrated a positive association between ΔLVEDVi and MMP-9 expression, but a negative correlation between ΔLVEDVi and CXCL1 expression. CONCLUSION: This is the first study indicating that BE in STEMI patients can alleviate adverse LV remodelling associated with beneficial energy metabolism adaptation, inflammation curbing, and extracellular matrix organization adjustment.
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Qigong/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Infarto do Miocárdio com Supradesnível do Segmento ST/reabilitação , Remodelação Ventricular/fisiologia , Fatores Etários , Idoso , Índice de Massa Corporal , Comorbidade , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteômica , Fatores Sexuais , Função Ventricular Esquerda/fisiologiaRESUMO
We tested the hypothesis that adjunctive thrombolysis at time of primary percutaneous coronary intervention (PCI) may affect favourably the long-term outcome of patients with ST elevation myocardial infarction (STEMI). To this end, we undertook a substudy of the DISSOLUTION (Delivery of thrombolytIcs before thrombectomy in patientS with ST-segment elevatiOn myocardiaL infarction Undergoing primary percuTaneous coronary interventION) trial. A total of 95 patients were randomized to local delivery of urokinase (n = 48) or placebo (n = 47). After PCI, a greater proportion of patients receiving urokinase had an improvement in myocardial perfusion, as indicated by a significantly higher final Thrombolysis in myocardial infarction (TIMI) grade 3, myocardial blush grade, and 60-min ST-segment resolution > 70%, as well as lower corrected TIMI frame count. At 1-year echocardiography, urokinase-treated patients exhibited significantly lower LV dimension, as well as higher LV ejection fraction and wall motion score index as compared with placebo-treated patients. At 5 years, major acute cardiovascular events (MACEs) were significantly less common in the urokinase group (P = 0.023), mainly due to a lower occurrence of hospitalisation for heart failure (P = 0.038). Multivariate analysis showed that factors independently associated with 5-year occurrence of MACEs were LV remodelling at 1-year echocardiography (P = 0.0001), 1-year LV ejection fraction (P = 0.0001), TIMI grade flow 0-2 (P = 0.0019), and age at time of PCI (P = 0.0173). In conclusion, low-dose intracoronary urokinase during primary PCI is associated with a more favourable 5-year outcome of patients with STEMI.
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Fibrinolíticos/uso terapêutico , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Terapia Trombolítica , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Idoso , Feminino , Fibrinolíticos/administração & dosagem , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Ativador de Plasminogênio Tipo Uroquinase/administração & dosagemRESUMO
Myocardial infarction (MI) is one of the leading causes of heart-related deaths worldwide. Following MI, the hypoxic microenvironment triggers apoptosis, disrupts the extracellular matrix and forms a non-functional scar that leads towards adverse left ventricular (LV) remodelling. If left untreated this eventually leads to heart failure. Besides extensive advancement in medical therapy, complete functional recovery is never accomplished, as the heart possesses limited regenerative ability. In recent decades, the focus has shifted towards tissue engineering and regenerative strategies that provide an attractive option to improve cardiac regeneration, limit adverse LV remodelling and restore function in an infarcted heart. Acellular scaffolds possess attractive features that have made them a promising therapeutic candidate. Their application in infarcted areas has been shown to improve LV remodelling and enhance functional recovery in post-MI hearts. This review will summarise the updates on acellular scaffolds developed and tested in pre-clinical and clinical scenarios in the past five years with a focus on their ability to overcome damage caused by MI. It will also describe how acellular scaffolds alone or in combination with biomolecules have been employed for MI treatment. A better understanding of acellular scaffolds potentialities may guide the development of customised and optimised therapeutic strategies for MI treatment.
Assuntos
Cardiotônicos/farmacologia , Alicerces Teciduais , Remodelação Ventricular , Animais , Materiais Biocompatíveis , Cardiotônicos/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Matriz Extracelular/química , Vesículas Extracelulares/química , Terapia Genética/métodos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Infarto do Miocárdio/patologia , Polímeros/química , Proteínas/químicaRESUMO
The objective of this study was to evaluate Spondias mombin L. (SM) pulp and its influence on cardiac remodelling after myocardial infarction (MI). Male Wistar rats were assigned to four groups: a sham group (animals underwent simulated surgery) that received standard chow (S; n = 20), an infarcted group that received standard chow (MI; n = 24), an infarcted group supplemented with 100 mg of SM/kg bodyweight/d, (MIS100; n = 23) and an infarcted group supplemented with 250 mg of SM/kg bodyweight/d (MIS250; n = 22). After 3 months of treatment, morphological, functional and biochemical analyses were performed. MI induced structural and functional changes in the left ventricle with worsening systolic and diastolic function, and SM supplementation at different doses did not influence these variables as analysed by echocardiography and an isolated heart study (P > .05). However, SM supplementation attenuated cardiac remodelling after MI, reducing fibrosis (P = .047) and hypertrophy (P = .006). Biomarkers of oxidative stress, inflammatory processes and energy metabolism were further investigated in the myocardial tissue. SM supplementation improved the efficiency of energy metabolism and decreased lipid hydroperoxide in the myocardium [group S (n = 8): 267.26 ± 20.7; group MI (n = 8): 330.14 ± 47.3; group MIS100 (n = 8): 313.8 ± 46.2; group MIS250: 294.3 ± 38.0 nmol/mg tissue; P = .032], as well as decreased the activation of the inflammatory pathway after MI. In conclusion, SM supplementation attenuated cardiac remodelling processes after MI. We also found that energy metabolism, oxidative stress and inflammation are associated with this effect. In addition, SM supplementation at the highest dose is more effective.
Assuntos
Anacardiaceae/química , Suplementos Nutricionais , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Estresse Oxidativo , Extratos Vegetais/farmacologia , Remodelação Ventricular , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Biomarcadores , Peso Corporal , Cromatografia Líquida de Alta Pressão , Citocinas/metabolismo , Modelos Animais de Doenças , Ecocardiografia , Metabolismo Energético/efeitos dos fármacos , Testes de Função Cardíaca , Imuno-Histoquímica , Mediadores da Inflamação/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/etiologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Ratos , Remodelação Ventricular/efeitos dos fármacosRESUMO
Despite significant advances in the prevention and treatment of heart failure (HF), the prognosis in patients who have been hospitalised on at least one occasion due to exacerbation of HF is still poor. Therefore, a better understanding of the underlying pathophysiological mechanisms of HF is crucial in order to achieve better results in the treatment of this clinical syndrome. One of the areas that, for years, has aroused the interest of researchers is the activation of the immune system and the elevated levels of biomarkers of inflammation in patients with both ischaemic and non-ischaemic HF. Additionally, it is intriguing that the level of circulating pro-inflammatory biomarkers correlates with the severity of the disease and prognosis in this group of patients. Unfortunately, clinical trials aimed at assessing interventions to modulate the inflammatory response in HF have been disappointing, and the modulation of the inflammatory response has had either no effect or even a negative effect on the HF prognosis. The article presents a summary of current knowledge on the role of immune system activation and inflammation in the pathogenesis of HF. Understanding the immunological mechanisms pathogenetically associated with left ventricular remodelling and progression of HF may open up new therapeutic possibilities for HF.
Assuntos
Insuficiência Cardíaca/fisiopatologia , Inflamação/metabolismo , Volume Sistólico/fisiologia , Remodelação Ventricular/fisiologia , Progressão da Doença , Insuficiência Cardíaca/metabolismo , Humanos , Inflamação/fisiopatologia , PrognósticoRESUMO
AIMS: Sudden cardiac death (SCD) risk estimation in patients referred for cardiac resynchronization therapy (CRT) remains a challenge. By CRT-mediated improvement of left ventricular ejection fraction (LVEF), many patients loose indication for primary prevention implantable cardioverter-defibrillator (ICD). Increasing evidence shows the importance of myocardial scar for risk prediction. The aim of this study was to investigate the prognostic impact of myocardial scar depending on the echocardiographic response in patients undergoing CRT. METHODS AND RESULTS: Patients with indication for CRT were prospectively enrolled. Decision about ICD or pacemaker implantation was based on clinical criteria. All patients underwent delayed-enhancement cardiac magnetic resonance imaging. Median follow-up duration was 45 (24-75) months. Primary outcome was a composite of sustained ventricular arrhythmia, appropriate ICD therapy, or SCD. A total of 218 patients with LVEF 25.5 ± 6.6% were analysed [158 (73%) male, 64.9 ± 10.7 years]. Myocardial scar was observed in 73 patients with ischaemic cardiomyopathy (ICM) (95% of ICM patients); in 62 with non-ischaemic cardiomyopathy (45% of these patients); and in all but 1 of 36 (17%) patients who reached the primary outcome. Myocardial scar was the only significant predictor of primary outcome [odds ratio 27.7 (3.8-202.7)], independent of echocardiographic CRT response. A total of 55 (25%) patients died from any cause or received heart transplant. For overall survival, only a combination of the absence of myocardial scar with CRT response was associated with favourable outcome. CONCLUSION: Malignant arrhythmic events and SCD depend on the presence of myocardial scar but not on CRT response. All-cause mortality improved only with the combined absence of myocardial scar and CRT response.