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1.
Artigo em Inglês | MEDLINE | ID: mdl-38888433

RESUMO

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have emerged as pivotal medications for heart failure, demonstrating remarkable cardiovascular benefits extending beyond their glucose-lowering effects. The unexpected cardiovascular advantages have intrigued and prompted the scientific community to delve into the mechanistic underpinnings of these novel actions. Pre-clinical studies have generated many mechanistic theories, ranging from their renal and extra-renal effects to potential direct actions on cardiac muscle cells, to elucidate the mechanisms linking these drugs to clinical cardiovascular outcomes. Despite the strengths and limitations of each theory, many await validation in human studies. Furthermore, whether SGLT2 inhibitors confer therapeutic benefits in specific subsets of cardiomyopathies akin to their efficacy in other heart failure populations remains unclear. By examining the shared pathological features between heart failure resulting from vascular diseases and other causes of cardiomyopathy, certain specific molecular actions of SGLT2 inhibitors (particularly those targeting cardiomyocytes) would support the concept that these medications will yield therapeutic benefits across a broad range of cardiomyopathies. This article aims to discuss important mechanisms of SGLT2 inhibitors and their implications in hypertrophic and dilated cardiomyopathies. Furthermore, we offer insights into future research directions for SGLT2 inhibitor studies, which hold the potential to further elucidate the proposed biological mechanisms in greater detail.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39163574

RESUMO

Right ventricular (RV) fibrosis is associated with RV dysfunction in a variety of RV pressure-loading conditions where RV mechanical stress is increased, but the underlying mechanisms driving RV fibrosis are incompletely understood. In pulmonary and cardiovascular diseases characterized by elevated mechanical stress and transforming growth factor - beta-1 (TGF-ß1) signaling, myocardin-related transcription factor A (MRTF-A) is a mechanosensitive protein critical to driving myofibroblast transition and fibrosis. Here we investigated whether MRTF-A inhibition improves RV pro-fibrotic remodeling and function in response to a pulmonary artery banding (PAB) model of RV pressure-loading. Rats were assigned into either 1) sham or 2) PAB groups. MRTF-A inhibitor CCG-1423 was administered daily at 0.75mg/kg in a subset of PAB animals. Echocardiography and pressure-volume hemodynamics were obtained at a terminal experiment 6-weeks later. RV myocardial samples were analyzed for fibrosis, cardiomyocyte hypertrophy, and pro-fibrotic signaling. MRTF-A inhibition slightly reduced systolic dysfunction in PAB rats reflected by increased lateral tricuspid annulus peak systolic velocity, while diastolic function parameters were not significantly improved. RV remodeling was attenuated in PAB rats with MRTF-A inhibition, displaying reduced fibrosis. This was accompanied with a reduction in PAB-induced upregulation of yes-associated protein (YAP) and its paralog transcriptional co-activator with PDZ-binding motif (TAZ). We also confirmed using a second-generation MRTF-A inhibitor CCG-203971 that MRTF-A is critical in driving RV fibroblast expression of TAZ and markers of myofibroblast transition in response to TGF-ß1 stress and RhoA activation. These studies identify RhoA, MRTF-A, and YAP/TAZ as interconnected regulators of pro-fibrotic signaling in RV pressure-loading, and as potential targets to improve RV pro-fibrotic remodeling.

3.
Am J Physiol Cell Physiol ; 327(2): C387-C402, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38912734

RESUMO

RhoA and its effectors, the transcriptional coactivators myocardin-related transcription factor (MRTF) and serum response factor (SRF), control epithelial phenotype and are indispensable for profibrotic epithelial reprogramming during fibrogenesis. Context-dependent control of RhoA and fibrosis-associated changes in its regulators, however, remain incompletely characterized. We previously identified the guanine nucleotide exchange factor GEF-H1 as a central mediator of RhoA activation in renal tubular cells exposed to inflammatory or fibrotic stimuli. Here we found that GEF-H1 expression and phosphorylation were strongly elevated in two animal models of fibrosis. In the Unilateral Ureteral Obstruction mouse kidney fibrosis model, GEF-H1 was upregulated predominantly in the tubular compartment. GEF-H1 was also elevated and phosphorylated in a rat pulmonary artery banding (PAB) model of right ventricular fibrosis. Prolonged stimulation of LLC-PK1 tubular cells with tumor necrosis factor (TNF)-α or transforming growth factor (TGF)-ß1 increased GEF-H1 expression and activated a luciferase-coupled GEF-H1 promoter. Knockdown and overexpression studies revealed that these effects were mediated by RhoA, cytoskeleton remodeling, and MRTF, indicative of a positive feedback cycle. Indeed, silencing endogenous GEF-H1 attenuated activation of the GEF-H1 promoter. Of importance, inhibition of MRTF using CCG-1423 prevented GEF-H1 upregulation in both animal models. MRTF-dependent increase in GEF-H1 was prevented by inhibition of the transcription factor Sp1, and mutating putative Sp1 binding sites in the GEF-H1 promoter eliminated its MRTF-dependent activation. As the GEF-H1/RhoA axis is key for fibrogenesis, this novel MRTF/Sp1-dependent regulation of GEF-H1 abundance represents a potential target for reducing renal and cardiac fibrosis.NEW & NOTEWORTHY We show that expression of the RhoA regulator GEF-H1 is upregulated in tubular cells exposed to fibrogenic cytokines and in animal models of kidney and heart fibrosis. We identify a pathway wherein GEF-H1/RhoA-dependent MRTF activation through its noncanonical partner Sp1 upregulates GEF-H1. Our data reveal the existence of a positive feedback cycle that enhances Rho signaling through control of both GEF-H1 activation and expression. This feedback loop may play an important role in organ fibrosis.


Assuntos
Fibrose , Fatores de Troca de Nucleotídeo Guanina Rho , Fator de Transcrição Sp1 , Transativadores , Proteína rhoA de Ligação ao GTP , Animais , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp1/genética , Proteína rhoA de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/genética , Fatores de Troca de Nucleotídeo Guanina Rho/metabolismo , Fatores de Troca de Nucleotídeo Guanina Rho/genética , Transativadores/metabolismo , Transativadores/genética , Camundongos , Ratos , Retroalimentação Fisiológica , Masculino , Camundongos Endogâmicos C57BL , Humanos , Transdução de Sinais , Suínos , Fosforilação , Modelos Animais de Doenças , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia , Obstrução Ureteral/genética , Ratos Sprague-Dawley , Linhagem Celular , Fatores de Transcrição
4.
Am J Physiol Heart Circ Physiol ; 326(3): H670-H688, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38133623

RESUMO

Modulation of the renin-angiotensin-aldosterone system is a foundation of therapy for cardiovascular and kidney diseases. Excess aldosterone plays an important role in cardiovascular disease, contributing to inflammation, fibrosis, and dysfunction in the heart, kidneys, and vasculature through both genomic and mineralocorticoid receptor (MR)-mediated as well as nongenomic mechanisms. MR antagonists have been a key therapy for attenuating the pathologic effects of aldosterone but are associated with some side effects and may not always adequately attenuate the nongenomic effects of aldosterone. Aldosterone is primarily synthesized by the CYP11B2 aldosterone synthase enzyme, which is very similar in structure to other enzymes involved in steroid biosynthesis including CYP11B1, a key enzyme involved in glucocorticoid production. Lack of specificity for CYP11B2, off-target effects on the hypothalamic-pituitary-adrenal axis, and counterproductive increased levels of bioactive steroid intermediates such as 11-deoxycorticosterone have posed challenges in the development of early aldosterone synthase inhibitors such as osilodrostat. In early-phase clinical trials, newer aldosterone synthase inhibitors demonstrated promise in lowering blood pressure in patients with treatment-resistant and uncontrolled hypertension. It is therefore plausible that these agents offer protection in other disease states including heart failure or chronic kidney disease. Further clinical evaluation will be needed to clarify the role of aldosterone synthase inhibitors, a promising class of agents that represent a potentially major therapeutic advance.


Assuntos
Cardiopatias , Hipertensão Renal , Nefrite , Humanos , Citocromo P-450 CYP11B2/genética , Citocromo P-450 CYP11B2/metabolismo , Aldosterona/farmacologia , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Hipertensão Renal/tratamento farmacológico , Sistema Renina-Angiotensina , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Cardiopatias/tratamento farmacológico
5.
Cardiovasc Diabetol ; 23(1): 72, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360604

RESUMO

BACKGROUND: The 2022 Canadian Cardiovascular Society (CCS) cardiorenal guideline provided clinical recommendations on sodium-glucose co-transport 2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1RA) use. Since then, additional trials of relevance for SGLT2i have been published. This update re-evaluates the clinical recommendations for using SGLTi and their indirect comparison with existing evidence on GLP-1RA as compared to the standard of care to reduce cardiorenal morbidity and mortality. METHODS: We updated our existing search and screening of the literature from September 2021 to April 2023 for randomized controlled trials of SGLT2i and GLP-1RA with placebo control. We conducted risk of bias assessment, data extraction and updated our meta-analysis of studies with similar interventions and components. The certainty of the evidence was determined using GRADE. RESULTS: Evidence from three new trials and additional results from an updated existing trial on SGLT2i met our inclusion criteria after an updated search. Across all the included studies, the total sample size was 151,023 adults, with 90,943 in SGLT2i trials and 60,080 in GLP-1 RA trials. The mean age ranged from 59.9 to 68.4 years. Compared with standard care, the use of SGLT2i and GLP-1 RA showed significant reductions in the outcomes of cardiovascular (CV) mortality (14% & 13%), any-cause mortality (12% & 12%), major adverse CV events (MACE) (11% & 14%), heart failure (HF) hospitalization (30% & 9%), CV death or HF hospitalization (23% & 11%), and kidney composite outcome (32% & 22%). In participants with T2D, both classes demonstrated significant cardiorenal protection. But, only GLP-1RA showed a reduction in non-fatal stroke (16%) and only SGLT2i showed a reduction in HF hospitalization (30%) in this population of people living with T2D. CONCLUSIONS: This updated and comprehensive meta-analysis substantiates and strengthens the clinical recommendations of the CCS cardiorenal guidelines.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Inibidores do Transportador 2 de Sódio-Glicose , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Canadá , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Insuficiência Cardíaca/prevenção & controle , Hipoglicemiantes/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico
6.
Curr Opin Cardiol ; 39(2): 92-97, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38294186

RESUMO

PURPOSE OF REVIEW: Heart failure with preserved ejection fraction (HFpEF) is a leading and growing cause of morbidity and mortality globally. Of the various phenotypes identified, the obesity (or cardiometabolic) phenotype appears to be most common. The purpose of this review is to provide the clinician with an abridged understanding of recent developments that have elucidated obesity/visceral adiposity as a central mechanism linking inflammation/immune dysregulation to the development of the HFpEF syndrome. Recent clinical trials examining the efficacy of pharmacological treatments that target obesity in HFpEF will also be discussed. RECENT FINDINGS: Recent data indicate that visceral adiposity and insulin resistance in HFpEF serve as key mechanisms driving inflammation and immune dysregulation, which play a critical role in the development of cardiac stiffness, diastolic dysfunction and fibrosis in HFpEF. In obesity, alterations in macrophage polarization, changes in innate and adaptive immune systems and altered myocardial energetics promote metabolic inflammation in HFpEF. Finally, emerging data suggest that inflammatory biomarkers, specifically, IL-6, may provide useful information about HFpEF severity and symptom burden in obesity. SUMMARY: The obesity phenotype of HFpEF is seen in upward of 80% with HFpEF. Obesity is not just a bystander, but plays an essential role in the pathobiology and clinical course of HFpEF. Targeting overweight/obesity in HFpEF with GLP-1 receptor agonists holds promise in these patients.


Assuntos
Insuficiência Cardíaca , Humanos , Volume Sistólico/fisiologia , Obesidade/complicações , Fenótipo , Inflamação
7.
Stem Cells Transl Med ; 13(7): 625-636, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38733609

RESUMO

The management of diabetes mellitus and its resultant end organ dysfunction represents a major challenge to global health-care systems. Diabetic cardiac and kidney disease commonly co-occur and are significant contributors to the morbidity and mortality of patients with diabetes, carrying a poor prognosis. The tight link of these parallel end organ manifestations suggests a deeper common underlying pathology. Here, we outline the mechanistic link between diabetic cardiac and kidney disease, providing evidence for the role of endothelial dysfunction in both processes and the potential for cellular therapy to correct these disorders. Specifically, we review the preclinical and clinical evidence for endothelial progenitor cell therapy in cardiac, kidney, and cardio-renal disease applications. Finally, we outline novel approaches to endothelial progenitor cell therapy through cell enhancement and the use of extracellular vesicles, discussing published and future work.


Assuntos
Células Progenitoras Endoteliais , Humanos , Células Progenitoras Endoteliais/metabolismo , Animais , Nefropatias Diabéticas/terapia , Transplante de Células-Tronco/métodos , Vesículas Extracelulares/metabolismo
8.
PLoS One ; 19(3): e0294367, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38478534

RESUMO

High volume endurance training may increase the risk of paroxysmal atrial fibrillation (AF) in middle-aged athletes. Limited data are available describing the cardiovascular phenotype of middle-aged endurance athletes, or the impact of AF on atrial function and exercise performance performed in sinus rhythm. The purpose of this study was to characterize LA phasic function at rest and during exercise in athletes with paroxysmal AF, and to determine its impact on exercise performance. Fifteen endurance trained males (EA) (56 ± 5 years) without AF and 14 endurance trained males with paroxysmal AF (EA-AF) (55 ± 8 years) underwent echocardiography during cycle-ergometry at light and moderate intensities. Resting LA maximal volumes were similar between EA and EA-AF (30 ± 4 vs. 29 ± 8 ml/m2, p = 0.50), and there were no differences in atrial electromechanical delay (AEMD). During moderate intensity exercise, EA-AF had reduced LA conduit (30 ± 6 vs. 40 ± 5 ml/m2, p = 0.002) LA booster volumes (17 ± 5 vs. 21 ± 4 ml/m2, p = 0.021), and reduced LV stroke volumes (100 ± 12 vs. 117 ± 16 ml, p = 0.007). These results demonstrate that exercise testing in athletes with AF unmasks evidence of adverse functional cardiac remodelling that may contribute to impaired exercise performance. It is unclear whether these functional alterations are the consequence of AF. Reductions in LA conduit volume, LA booster volume, and LV stroke volume during exercise may be helpful in clinical management and distinguishing pathologic from physiologic remodelling.


Assuntos
Fibrilação Atrial , Masculino , Pessoa de Meia-Idade , Humanos , Átrios do Coração/diagnóstico por imagem , Ecocardiografia , Exercício Físico , Atletas
9.
J Am Heart Assoc ; 13(6): e033640, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38497478

RESUMO

BACKGROUND: Atrial fibrillation (AF) is a common arrhythmia characterized by uncoordinated atrial electrical activity. Lone AF occurs in the absence of traditional risk factors and is frequently observed in male endurance athletes, who face a 2- to 5-fold higher risk of AF compared with healthy, moderately active males. Our understanding of how endurance exercise contributes to the pathophysiology of lone AF remains limited. This study aimed to characterize the circulating protein fluctuations during high-intensity exercise as well as explore potential biomarkers of exercise-associated AF. METHODS AND RESULTS: A prospective cohort of 12 male endurance cyclists between the ages of 40 and 65 years, 6 of whom had a history of exercise-associated AF, were recruited to participate using a convenience sampling method. The circulating proteome was subsequently analyzed using multiplex immunoassays and aptamer-based proteomics before, during, and after an acute high-intensity endurance exercise bout to assess temporality and identify potential markers of AF. The endurance exercise bout resulted in significant alterations to proteins involved in immune modulation (eg, growth/differentiation factor 15), skeletal muscle metabolism (eg, α-actinin-2), cell death (eg, histones), and inflammation (eg, interleukin-6). Subjects with AF differed from those without, displaying modulation of proteins previously known to have associations with incident AF (eg, C-reactive protein, insulin-like growth factor-1, and angiopoietin-2), and also with proteins having no previous association (eg, tapasin-related protein and α2-Heremans-Schmid glycoprotein). CONCLUSIONS: These findings provide insights into the proteomic response to acute intense exercise, provide mechanistic insights into the pathophysiology behind AF in athletes, and identify targets for future study and validation.


Assuntos
Fibrilação Atrial , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Proteômica , Exercício Físico/fisiologia , Atletas , Fatores de Risco , Resistência Física/fisiologia
10.
Heart Rhythm ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38848857

RESUMO

Diabetes mellitus (DM) confers an increased risk of sudden cardiac death (SCD) independent of its associated cardiovascular comorbidities. DM induces adverse structural, electrophysiologic, and autonomic cardiac remodeling that can increase one's risk of ventricular arrhythmias and SCD. Although glycemic control and prevention of microvascular and macrovascular complications are cornerstones in the management of DM, they are not adequate for the prevention of SCD. In this narrative review, we describe the contribution of DM to the pathophysiologic mechanism of SCD beyond its role in atherosclerotic cardiovascular disease and heart failure. On the basis of this pathophysiologic framework, we outline potential preventive and therapeutic strategies to mitigate the risk of SCD in this population of high-risk patients.

11.
Int J Cardiol ; 403: 131892, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38382853

RESUMO

BACKGROUND: Cardiac amyloidosis is increasingly recognized as a significant contributor to cardiovascular morbidity and mortality. With the emergence of novel therapies, there is a growing interest in prognostication of patients with cardiac amyloidosis using cardiac magnetic resonance imaging (CMR). In this systematic review and meta-analysis, we aimed to examine the prognostic significance of myocardial native T1 and T2, and extracellular volume (ECV). METHODS: Observational cohort studies or single arms of clinical trials were eligible. MEDLINE, EMBASE and CENTRAL were systematically searched from their respective dates of inception to January 2023. No exclusions were made based on date of publication, study outcomes, or study language. The study populations composed of adult patients (≥18 years old) with amyloid cardiomyopathy. All studies included the use of CMR with and without intravenous gadolinium contrast administration to assess myocardial native T1 mapping, T2 mapping, and ECV in association with the pre-specified primary outcome of all-cause mortality. Data were extracted from eligible primary studies by two independent reviewers and pooled via the inverse variance method using random effects models for meta-analysis. RESULTS: A total of 3852 citations were reviewed. A final nine studies including a total of 955 patients (mean age 65 ± 10 years old, 32% female, mean left ventricular ejection fraction (LVEF) 59 ± 12% and 24% had NYHA class III or IV symptoms) with cardiac amyloidosis [light chain amyloidosis (AL) 50%, transthyretin amyloidosis (ATTR) 49%, other 1%] were eligible for inclusion and suitable for data extraction. All included studies were single centered (seven with 1.5 T MRI scanners, two with 3.0 T MRI scanners) and non-randomized in design, with follow-up spanning from 8 to 64 months (median follow-up = 25 months); 320 patients died during follow-up, rendering a weighted mortality rate of 33% across studies. Compared with patients with AL amyloid, patients with ATTR amyloid had significantly higher mean left ventricular mass index (LVMi) (102 ± 34 g/m2 vs 127 ± 37 g/m2, p = 0.02). N-terminal pro-brain natriuretic peptide (NT-proBNP), troponin T levels, mean native T1 values, ECV and T2 values did not differ between patients with ATTR amyloid and AL amyloid (all p > 0.25). Overall, the hazard ratios for mortality were 1.33 (95% CI = [1.10, 1.60]; p = 0.003; I2 = 29%) for every 60 ms higher T1 time, 1.16 (95% CI = [1.09, 1.23], p < 0.0001; I2 = 76%) for every 3% higher ECV, and 5.23 (95% CI = [2.27, 12.02]; p < 0.0001; I2 = 0%) for myocardial-to-skeletal T2 ratio below the mean (vs above the mean). CONCLUSION: Higher native T1 time and ECV, and lower myocardial to skeletal T2 ratio, on CMR are associated with worse mortality in patients with cardiac amyloidosis. Therefore, tissue mapping using CMR may offer a useful non-invasive technique to monitor disease progression and determine prognosis in patients with cardiac amyloidosis.

12.
J Am Coll Cardiol ; 83(7): 755-769, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38355246

RESUMO

BACKGROUND: South Asian individuals shoulder a disproportionate burden of cardiometabolic diseases. OBJECTIVES: The purpose of this study was to determine if vascular regenerative cell content varies significantly between South Asian and White European people. METHODS: Between January 2022 and January 2023, 60 South Asian and 60 White European adults with either documented cardiovascular disease or established diabetes with ≥1 other cardiovascular risk factor were prospectively enrolled. Vascular regenerative cell content in venous blood was enumerated using a flow cytometry assay that is based on high aldehyde dehydrogenase (ALDHhi) activity and cell surface marker phenotyping. The primary outcome was the difference in frequency of circulating ALDHhi progenitor cells, monocytes, and granulocytes between the 2 groups. RESULTS: Compared with White European participants, those of South Asian ethnicity were younger (69 ± 10 years vs 66 ± 9 years; P < 0.05), had lower weight (88 ± 19 kg vs 75 ± 13 kg; P < 0.001), and exhibited a greater prevalence of type 2 diabetes (62% vs 92%). South Asian individuals had markedly lower circulating frequencies of pro-angiogenic ALDHhiSSClowCD133+ progenitor cells (P < 0.001) and ALDHhiSSCmidCD14+CD163+ monocytes with vessel-reparative capacity (P < 0.001), as well as proportionally more ALDHhi progenitor cells with high reactive oxygen species content (P < 0.05). After correction for sex, age, body mass index, and glycated hemoglobin, South Asian ethnicity was independently associated with lower ALDHhiSSClowCD133+ cell count. CONCLUSIONS: South Asian people with cardiometabolic disease had less vascular regenerative and reparative cells suggesting compromised vessel repair capabilities that may contribute to the excess vascular risk in this population. (The Role of South Asian vs European Origins on Circulating Regenerative Cell Exhaustion [ORIGINS-RCE]; NCT05253521).


Assuntos
Diabetes Mellitus Tipo 2 , Humanos
13.
J Appl Physiol (1985) ; 136(5): 1245-1259, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38385183

RESUMO

Anemia and renal failure are independent risk factors for perioperative stroke, prompting us to assess the combined impact of acute hemodilutional anemia and bilateral nephrectomy (2Nx) on microvascular brain Po2 (PBro2) in a rat model. Changes in PBro2 (phosphorescence quenching) and cardiac output (CO, echocardiography) were measured in different groups of anesthetized Sprague-Dawley rats (1.5% isoflurane, n = 5-8/group) randomized to Sham 2Nx or 2Nx and subsequently exposed to acute hemodilutional anemia (50% estimated blood volume exchange with 6% hydroxyethyl starch) or time-based controls (no hemodilution). Outcomes were assessed by ANOVA with significance assigned at P < 0.05. At baseline, 2Nx rats demonstrated reduced CO (49.9 ± 9.4 vs. 66.3 ± 19.3 mL/min; P = 0.014) and PBro2 (21.1 ± 2.9 vs. 32.4 ± 3.1 mmHg; P < 0.001) relative to Sham 2Nx rats. Following hemodilution, 2Nx rats demonstrated a further decrease in PBro2 (15.0 ± 6.3 mmHg, P = 0.022). Hemodiluted 2Nx rats did not demonstrate a comparable increase in CO after hemodilution compared with Sham 2Nx (74.8 ± 22.4 vs. 108.9 ± 18.8 mL/min, P = 0.003) that likely contributed to the observed reduction in PBro2. This impaired CO response was associated with reduced fractional shortening (33 ± 9 vs. 51 ± 5%) and increased left ventricular end-systolic volume (156 ± 51 vs. 72 ± 15 µL, P < 0.001) suggestive of systolic dysfunction. By contrast, hemodiluted Sham 2Nx animals demonstrated a robust increase in CO and preserved PBro2. These data support the hypothesis that the kidney plays a central role in maintaining cerebral perfusion and initiating the adaptive increase in CO required to optimize PBro2 during acute anemia.NEW & NOTEWORTHY This study has demonstrated that bilateral nephrectomy acutely impaired cardiac output (CO) and microvascular brain Po2 (PBro2), at baseline. Following acute hemodilution, nephrectomy prevented the adaptive increase in CO associated with acute hemodilution leading to a further reduction in PBro2, accentuating the degree of cerebral tissue hypoxia. These data support a role for the kidney in maintaining PBro2 and initiating the increase in CO that optimized brain perfusion during acute anemia.


Assuntos
Anemia , Débito Cardíaco , Circulação Cerebrovascular , Hemodiluição , Nefrectomia , Ratos Sprague-Dawley , Animais , Hemodiluição/métodos , Nefrectomia/métodos , Ratos , Masculino , Circulação Cerebrovascular/fisiologia , Anemia/fisiopatologia , Débito Cardíaco/fisiologia , Modelos Animais de Doenças , Encéfalo/fisiopatologia
14.
Int J Cardiol ; 405: 131934, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38437953

RESUMO

AIMS: T-TEER is an effective therapy for the treatment of tricuspid regurgitation (TR). However, the effects of leaflets clipping on tricuspid valve annulus (TA) have not been investigated in detail. The aim of this study is to investigate the effects of tricuspid transcatheter edge-to-edge repair (T-TEER) on TA diameter. METHODS AND RESULTS: The TriValve registry (Transcatheter Tricuspid Valve Therapies, NCT03416166) collected 556 patients from 22 European and North American centres undergoing transcatheter tricuspid valve interventions from 2016 to 2022. Patients undergoing T-TEER with available pre- and post-procedural data on TA diameter measured in the apical 4-chamber view on transthoracic echocardiography were selected for this study. Primary end-point was the reduction of TA diameter after T-TEER. A total of 186 patients were included in the study. In 115 patients (62%) TA diameter was reduced by at least 1 mm as compared to baseline. A significant reduction of TA dimension was observed following T-TEER (mean 2.3 mm [from pre-procedural diameter 46.7 mm to post-procedural diameter 44.4 mm], p < 0.001). In particular, the greatest reduction was observed in those with T-TEER in antero-septal commissure (mean 2.7 mm [from 47.1 mm to 44.4 mm], p < 0.001) as compared to those combining both antero-septal and postero-septal commissures (mean 1.4, from 46.0 mm to 44.6 mm, P = 0.06). A significant reduction of TA dimension was recorded in patients with 1 or 2 clips implanted but not in those patients with ≥3 clips implanted. CONCLUSIONS: In almost two third of patients T-TEER reduces TA diameter in addition to leaflet approximation. CONDENSED ABSTRACT: The effects of tricuspid transcatheter edge-to-edge repair (T-TEER) on tricuspid valve annulus (TA) have not been studied in details. This study investigates TA diameter as measured in apical 4-chamber view on transthoracic echocardiography before and after T-TEER. A total of 186 patients from the TriValve registry were included in the study. The study results show that 62% of patients have a TA reduction after T-TEER, especially in those receiving 1 or 2 clips in the antero-septal commissure. These suggest that T-TEER reduces tricuspid regurgitation not only by approximation of leaflets, but also by TA diameter reduction.


Assuntos
Cateterismo Cardíaco , Sistema de Registros , Insuficiência da Valva Tricúspide , Valva Tricúspide , Humanos , Masculino , Feminino , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia , Idoso , Insuficiência da Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Cateterismo Cardíaco/métodos , Idoso de 80 Anos ou mais , Resultado do Tratamento , Implante de Prótese de Valva Cardíaca/métodos , Pessoa de Meia-Idade , Ecocardiografia/métodos
15.
JACC Cardiovasc Interv ; 17(7): 859-870, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38599688

RESUMO

BACKGROUND: Data on the prognostic role of the TRI-SCORE in patients undergoing transcatheter tricuspid valve intervention (TTVI) are limited. OBJECTIVES: The aim of this study was to evaluate the performance of the TRI-SCORE in predicting outcomes of patients undergoing TTVI. METHODS: TriValve (Transcatheter Tricuspid Valve Therapies) is a large multicenter multinational registry including patients undergoing TTVI. The TRI-SCORE is a risk model recently proposed to predict in-hospital mortality after tricuspid valve surgery. The TriValve population was stratified based on the TRI-SCORE tertiles. The outcomes of interest were all-cause death and all-cause death or heart failure hospitalization. Procedural complications and changes in NYHA functional class were also reported. RESULTS: Among the 634 patients included, 223 patients (35.2%) had a TRI-SCORE between 0 and 5, 221 (34.8%) had 6 or 7, and 190 (30%) had ≥8 points. Postprocedural blood transfusion, acute kidney injury, new atrial fibrillation, and in-hospital mortality were more frequent in the highest TRI-SCORE tertile. Postprocedure length of stay increased with a TRI-SCORE increase. A TRI-SCORE ≥8 was associated with an increased risk of 30-day all-cause mortality and all-cause mortality and the composite endpoint assessed at a median follow-up of 186 days (OR: 3.00; 95% CI: 1.38-6.55; HR: 2.17; 95% CI: 1.78-4.13; HR: 2.08, 95% CI: 1.57-2.74, respectively) even after adjustment for procedural success and EuroSCORE II or Society of Thoracic Surgeons Predicted Risk of Mortality. The NYHA functional class improved across all TRI-SCORE values. CONCLUSIONS: In the TriValve registry, the TRI-SCORE has a suboptimal performance in predicting clinical outcomes. However, a TRISCORE ≥8 is associated with an increased risk of clinical events and a lack of prognostic benefit after successful TTVI.


Assuntos
Insuficiência Cardíaca , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Tricúspide , Humanos , Cateterismo Cardíaco/métodos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/etiologia , Resultado do Tratamento , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Insuficiência da Valva Tricúspide/cirurgia , Estudos Multicêntricos como Assunto , Sistema de Registros
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