Sepsis-induced cardiomyopathy is associated with higher mortality rates in patients with sepsis

Immune-response gene 1 deficiency aggravates inflammation-triggered cardiac dysfunction by inducing M1 macrophage polarization and aggravating Ly6Chigh monocyte recruitment

The immune response gene 1 (IRG1) and its metabolite itaconate are implicated in modulating inflammation and oxidative stress, with potential relevance to sepsis-induced myocardial dysfunction (SIMD). This study investigates their roles in SIMD using both in vivo and in vitro models. Mice were subjected to lipopolysaccharide (LPS)-induced sepsis, and cardiac function was assessed in IRG1 knockout (IRG1-/-) and wild-type mice. Exogenous 4-octyl itaconate (4-OI) supplementation was also examined for its protective effects. In vitro, bone marrow-derived macrophages and RAW264.7 cells were treated with 4-OI following Nuclear factor, erythroid 2 like 2 (NRF2)-small interfering RNA administration to elucidate the underlying mechanisms. Our results indicate that IRG1 deficiency exacerbates myocardial injury during sepsis, while 4-OI administration preserves cardiac function and reduces inflammation. Mechanistic insights reveal that 4-OI activates the NRF2/HO-1 pathway, promoting macrophage polarization and attenuating inflammation. These findings underscore the protective role of the IRG1/itaconate axis in SIMD and suggest a therapeutic potential for 4-OI in modulating macrophage responses.

Examining the relationship between alterations in plasma cholesterol, vascular endothelin-1 levels, and the severity of sepsis in children: An observational study

Considering the significant impact of total cholesterol (TC) and vascular endothelin-1 (ET-1) on children sepsis outcomes, this research aimed to explore the association between the levels of plasma cholesterol and vascular endothelin-1 and the severity of sepsis and evaluated its clinical implications. In this study, we examined 250 pediatric patients diagnosed with sepsis between February 2019 and April 2021, collecting data on their plasma levels of TC and ET-1. Depending on the observed outcomes, the participants were divided into 2 categories: a group with a positive prognosis (control group, n = 100) and a group with a negative prognosis (n = 50). We assessed the significance of plasma TC and ET-1 levels in forecasting the outcomes for these pediatric patients. Patients in the group with a poor prognosis experienced notably longer hospital stays and higher treatment expenses than those in the control group (P < .05). Within the first 24 hours of admission and again on days 3 and 7, the levels of ET-1 were significantly higher in the poor prognosis group, whereas plasma TC levels were notably lower in comparison to the control group (P < .05). A Spearman correlation analysis identified a significant correlation between the levels of plasma TC and ET-1 and the severity of sepsis among the children (P < .05). The diagnostic performance for the severity of sepsis in children, as measured by the area under the curve (AUC), was 0.805 for plasma TC, 0.777 for ET-1 levels, and 0.938 when both were combined. This investigation underscores a meaningful relationship between the levels of plasma TC and ET-1 in pediatric sepsis patients, suggesting these biomarkers are highly valuable in predicting patient outcomes. High levels of ET-1 and low levels of TC in these patients signify a grave condition and a poor prognosis.

The Usefulness of Strain Echocardiography as Diagnostic and Prognostic Index of Cardiac Dysfunction in Septic Patients in Correlation with Cardiac Biomarkers

Background

Compared to standard echocardiography, speckle tracking echocardiography (STE) looks more accurate for the detection of subclinical dysfunction of the myocardium. The aim of our work was to assess the value of STE in the diagnosis of subclinical ventricular dysfunction and as a prognostic index in sepsis patients.

Patients and Methods

An observational prospective study involving critically ill patients aged ≥ 18 years diagnosed with sepsis or septic shock. All patients were subjected to full history-taking, clinical assessment, and scoring system, including Acute Physiology and Chronic Health (APACHE) II score and quick sequential organ failure assessment score. Investigations were done for all patients, including laboratory (complete blood count, C-reactive protein, N-terminal pro-brain natriuretic peptide [NT-proBNP], and troponin-I and serum lactate level), ECG, and echocardiographic examination (conventional and speckle tracking) for measurement of global left ventricular strain.

Results

This study involved 50 patients, nine patients with sepsis and 41 patients with septic shock. Regarding cardiac biomarkers, the mean value of troponin-I was 0.18 ± 0.05 ng/L and for NT-proBNP was 1228.2 ± 832.9 pmol/L. All patients in the study had elevated lactate levels. There was a significant correlation between global longitudinal strain (GLS) and troponin I, NT-proBNP, and lactate levels after 3 days of admission. GLS, lactate, NT-proBNP, troponin levels, and APACHE II Score were significant predictors of mortality with a sensitivity of 76.5%, 88.2%, 88.2%, 76.5%, and 88.2%, respectively.

Conclusion

GLS measured by speckle tracking echocardiography looks to be a sensitive diagnostic tool for early detection of subclinical left ventricular dysfunction in patients with sepsis in addition to be a sensitive predictor of in-hospital mortality.

Inhibition of Pyruvate Dehydrogenase Kinase 4 Attenuates Myocardial and Mitochondrial Injury in Sepsis-Induced Cardiomyopathy

BACKGROUND

Sepsis-induced cardiomyopathy (SIC) is a cardiac dysfunction caused by sepsis, with mitochondrial dysfunction being a critical contributor. Pyruvate dehydrogenase kinase 4 (PDK4) is a kinase of pyruvate dehydrogenase with multifaceted actions in mitochondrial metabolism. However, its role in SIC remains unknown.

METHODS

Serum PDK4 levels were measured and analyzed in 27 children with SIC, 30 children with sepsis, and 29 healthy children. In addition, for mice exhibiting SIC, the effects of PDK4 knockdown or inhibition on the function and structure of the myocardium and mitochondria were assessed.

RESULTS

The findings from the analysis of children with SIC revealed that PDK4 was significantly elevated and correlated with disease severity and organ injury. Nonsurvivors displayed higher serum PDK4 levels than survivors. Furthermore, mice with SIC benefited from PDK4 knockdown or inhibition, showing improved myocardial contractile function, reduced myocardial injury, and decreased mitochondrial structural injury and dysfunction. In addition, inhibition of PDK4 decreased the inhibitory phosphorylation of PDHE1α (pyruvate dehydrogenase complex E1 subunit α) and improved abnormal pyruvate metabolism and mitochondrial dysfunction.

CONCLUSIONS

PDK4 is a potential biomarker for the diagnosis and prognosis of SIC. In experimental SIC, PDK4 promoted mitochondrial dysfunction with increased phosphorylation of PDHE1α and abnormal pyruvate metabolism.

Meta-analysis of initial natriuretic peptides in the setting of sepsis-induced myocardial dysfunction

Aim: To investigate the association of initial brain natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP) with the detection of sepsis-induced myocardial dysfunction (SIMD) in the setting of Sepsis 3.0. Methods: Three databases were searched to analyze initial BNP and NT-proBNP levels between SIMD and non-SIMD groups. Results: Eighteen studies were included, most of which defined SIMD based on echocardiography. The SIMD group exhibited higher initial BNP and NT-proBNP levels in blood. NT-proBNP higher than a certain cutoff value (>3000 pg/ml) was an independent risk factor for SIMD and its accuracy for SIMD diagnosis was moderate (pooled area under the curve: 0.81). Conclusion: Initial blood BNP and NT-proBNP levels are useful to assist in the detection of SIMD and further studies are warranted to determine the SIMD definition.

Research Progress on the Mechanism and Management of Septic Cardiomyopathy: A Comprehensive Review

Sepsis is defined as a kind of life-threatening organ dysfunction due to a dysregulated host immune response to infection and is a leading cause of mortality in the intensive care unit. Sepsis-induced myocardial dysfunction, also called septic cardiomyopathy, is a common and serious complication in patients with sepsis, which may indicate a bad prognosis. Although efforts have been made to uncover the pathophysiology of septic cardiomyopathy, a number of uncertainties remain. This article sought to review available literature to summarize the existing knowledge on current diagnostic tools and biomarkers, pathogenesis, and treatments for septic cardiomyopathy.

Prevalence and Prognosis of Sepsis-Induced Cardiomyopathy: A Systematic Review and Meta-Analysis

Purpose: The prevalence and its impact on mortality of sepsis-induced cardiomyopathy (SICM) remain controversial. In this systematic review and meta-analysis, we investigated the prevalence and prognosis of SICM. Materials and Methods: We searched MEDLINE, Cochrane Central Register of Controlled Trials, and Embase. Titles and abstracts were evaluated based on the following criteria: (1) published in English, (2) randomized controlled trials, cohort studies, or cross-sectional studies, (3) ≥ 18 years with sepsis, (4) reporting the prevalence and/or comparison of short-term mortality between those with and without SICM, defined as the new-onset reduction in left ventricular ejection fraction (LVEF) within 72 h on admission or from the diagnosis of sepsis. The random-effect model was used for all analyses. This meta-analysis was registered at PROSPERO (CDR42022332896). Results: Sixteen studies reported the prevalence of SICM and the pooled prevalence of SICM was 20% (95% confidence interval [CI], 16-25%; I2  =  89.9%, P < 0.01). Eleven studies reported short-term mortality and SICM was associated with significantly higher short-term mortality (The pooled odds ratio: 2.30, 95% CI, 1.43-3.69; I2  =  0%, P  =  0.001). Conclusion: The prevalence of SICM was 20% in patients with sepsis, and the occurrence of SICM was associated with significantly higher short-term mortality.

Sepsis-Induced myocardial dysfunction: heterogeneity of functional effects and clinical significance

Sepsis is a life-threatening disease state characterized by organ dysfunction and a dysregulated response to infection. The heart is one of the many organs affected by sepsis, in an entity termed sepsis-induced cardiomyopathy. This was initially used to describe a reversible depression in ejection fraction with ventricular dilation but advances in echocardiography and introduction of new techniques such as speckle tracking have led to descriptions of other common abnormalities in cardiac function associated with sepsis. This includes not only depression of systolic function, but also supranormal ejection fraction, diastolic dysfunction, and right ventricular dysfunction. These reports have led to inconsistent definitions of sepsis-induced cardiomyopathy. Just as there is heterogeneity among patients with sepsis, there is heterogeneity in the cardiac response; thus resuscitating these patients with a single approach is likely suboptimal. Many factors affect the heart in sepsis including inflammatory mediators, catecholamine responsiveness, and pathogen related toxins. This review will discuss different functional effects characterized by echocardiographic changes in sepsis and their prognostic and management implications.

RNF20 deletion causes inflammation in model of sepsis through the NLRP3 activation

Aim: Sepsis is an extremely complex, threatening and difficult-to-treat disease, which can occur at any age and under any underlying disease. RNF20 regulate NF-kappaB (NF-κB) signaling pathway and the transcription of inflammatory factors of target genes. Therefore, it is of great significance to study the function of RNF20 in the clinical treatment of sepsis and its underlying mechanisms.Methods: C57BL/6 mice were subjected to cecal ligation and puncture (CLP) surgery. THP-1 cells were induced with Lipopolysaccharide for 4 h.Results: RNF20 gene, mRNA expression and protein expression were reduced in patients with sepsis and mice with sepsis. Based on RNF20 deletion (RNF20^-/-) mice, these were found to be increased inflammation reactions in RNF20^-/- mice. However, the RNF20 human protein reduced inflammation reactions in mice with sepsis. In vitro model of sepsis, over-expression of RNF20 inhibited inflammation reactions by inducing Vitamin D Receptor (VDR), while down-regulation of RNF20 promoted inflammation reactions through the suppression of VDR. RNF20 protein was interlinked with VDR protein, and VDR protein was also interlinked with NLRP3. Furthermore, VDR promoted NLRP3 ubiquitination and reduced NLRP3 function in vitro model of sepsis.Conclusion: These studies demonstrate that RNF20 suppressed inflammation reactions in models with sepsis through NLRP3 inflammasome and NLRP3 ubiquitination by activating VDR.

Ultrasound in Sepsis and Septic Shock-From Diagnosis to Treatment

Sepsis and septic shock are among the leading causes of in-hospital mortality worldwide, causing a considerable burden for healthcare. The early identification of sepsis as well as the individuation of the septic focus is pivotal, followed by the prompt initiation of antibiotic therapy, appropriate source control as well as adequate hemodynamic resuscitation. For years now, both emergency department (ED) doctors and intensivists have used ultrasound as an adjunctive tool for the correct diagnosis and treatment of these patients. Our aim was to better understand the state-of-the art role of ultrasound in the diagnosis and treatment of sepsis and septic shock.

METHODS

We conducted an extensive literature search about the topic and reported on the data from the most significant papers over the last 20 years.

RESULTS

We divided each article by topic and exposed the results accordingly, identifying four main aspects: sepsis diagnosis, source control and procedure, fluid resuscitation and hemodynamic optimization, and echocardiography in septic cardiomyopathy.

CONCLUSION

The use of ultrasound throughout the process of the diagnosis and treatment of sepsis and septic shock provides the clinician with an adjunctive tool to better characterize patients and ensure early, aggressive, as well as individualized therapy, when needed. More data are needed to conclude that the use of ultrasound might improve survival in this subset of patients.

S100a8/a9 contributes to sepsis-induced cardiomyopathy by activating ERK1/2-Drp1-mediated mitochondrial fission and respiratory dysfunction

Sepsis-induced cardiomyopathy (SIC) is the main complication and a leading cause of death in intensive care units. S100a8/a9 is a calcium-binding protein that participates in various inflammatory diseases; however, its role in sepsis-induced cardiomyopathy and the underlying mechanism remains to be explored. Here, septic cardiomyopathy was induced with cecal ligation and puncture (CLP) in S100a9-knockout (KO) mice lacking the heterodimer S100a8/a9 or wild-type (WT) mice administered with an S100a9-specific inhibitor Paquinimod (Paq), which prevents the binding of S100a9 toTLR4. Our results showed that S100a8/a9 expression in the heart peaked 24 h following the CLP operation, declined at 48 h and returned to baseline at 72 h. Loss of S100a9 by knockout in mice protected against CLP-induced mortality, cardiac dysfunction, myocyte apoptosis, recruitment of Mac-2⁺ macrophages, superoxide production, and the expression of pro-inflammatory cytokines genes compared with WT mice. Moreover, S100a9-KO significantly attenuated CLP-induced activation of the ERK1/2-Drp1 (S616) pathway, excessive mitochondrial fission, and mitochondrial respiration dysfunction. In contrast, activation of ERK1/2 with its agonist tBHQ reversed the inhibitory effects of S100a9-knockout on CLP-induced cardiomyopathy and mitochondrial dysfunction. Finally, administration of Paq to WT mice markedly prevented the CLP-induced cardiomyopathy mitochondrial fission and dysfunction compared with vehicle control. In summary, our data reveal, for the first time, that S100a8/a9 plays a critical role in mediating SIC, presumably by activating TLR4-ERK1/2-Drp1-dependent mitochondrial fission and dysfunction and highlight that blockage of S100a8/a9 may be a promising therapeutic strategy to prevent SIC in patients with sepsis.

Therapeutic Dilemmas in Mixed Septic-Cardiogenic Shock

Sepsis is an increasing cause of decompensation in patients with chronic heart failure with reduced or preserved ejection fraction. Sepsis and decompensated heart failure results in a mixed septic-cardiogenic shock that poses several therapeutic dilemmas: Rapid fluid resuscitation is the cornerstone of sepsis management, while loop diuretics are the main stay of decompensated heart failure treatment. Whether inotropic therapy with dobutamine or inodilators improves microvascular alterations remains unsettled in sepsis. When to resume loop diuretic therapy in patients with sepsis and decompensated heart failure is unclear. In the absence of relevant guidelines, we review vasopressor therapy, the timing and volume of fluid resuscitation, and the need for inotropic therapy in patients who, with sepsis and decompensated heart failure, present with a mixed septic-cardiogenic shock.

A novel signature combing cuproptosis- and ferroptosis-related genes in sepsis-induced cardiomyopathy

Objective: Cardiac dysfunction caused by sepsis, usually termed sepsis-induced cardiomyopathy (SIC), is one of the most serious complications of sepsis, and ferroptosis can play a key role in this disease. In this study, we identified key cuproptosis- and ferroptosis-related genes involved in SIC and further explored drug candidates for the treatment of SIC. Methods: The GSE79962 gene expression profile of SIC patients was downloaded from the Gene Expression Omnibus database (GEO). The data was used to identify differentially expressed genes (DEGs) and to perform weighted correlation network analysis (WGCNA). Furthermore, Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted. Then, gene set enrichment analysis (GSEA) was applied to further analyze pathway regulation, with an adjusted p-value <0.05 and a false discovery rate (FDR) <0.25. Ferroptosis-related genes were obtained from the FerrDb V2 database, and cuproptosis-related genes were obtained from the literature. We constructed a novel signature (CRF) by combing cuproptosis-related genes with ferroptosis-related genes using the STRING website. The SIC hub genes were obtained by overlapping DEGs, WGCNA-based hub genes and CRF genes, and receiver operating characteristic (ROC) curve analysis was used to determine the diagnostic value of hub genes. A transcription factor-microRNA-hub gene network was also constructed based on the miRnet database. Finally, potential therapeutic compounds for SIC were predicted based on the Drug Gene Interaction Database. Results: We identified 173 DEGs in SIC patients. Four hub modules and 411 hub genes were identified by WGCNA. A total of 144 genes were found in the CRF. Then, POR, SLC7A5 and STAT3 were identified as intersecting hub genes and their diagnostic values were confirmed with ROC curves. Drug screening identified 15 candidates for SIC treatment. Conclusion: We revealed that the cuproptosis- and ferroptosis-related genes, POR, SLC7A5 and STAT3, were significantly correlated with SIC and we also predicted therapeutic drugs for these targets. The findings from this study will make contributions to the development of treatments for SIC.

Association of sepsis-induced cardiomyopathy and mortality: a systematic review and meta-analysis

BACKGROUND

The implication of sepsis-induced cardiomyopathy (SIC) to prognosis is controversial, and its association with mortality at different stages remains unclear. We conducted a systematic review and meta-analysis to understand the association between SIC and mortality in septic patients.

METHODS

We searched and appraised observational studies regarding the mortality related to SIC among septic patients in PubMed and Embase from inception until 8 July 2021. Outcomes comprised in-hospital and 1-month mortality. We adopted the random-effects model to examine the mortality risk ratio in patients with and without SIC. Meta-regression, subgroup, and sensitivity analyses were applied to examine the outcome's heterogeneity.

RESULTS

Our results, including 20 studies and 4,410 septic patients, demonstrated that SIC was non-statistically associated with increased in-hospital mortality, compared to non-SIC (RR 1.28, [0.96-1.71]; p = 0.09), but the association was statistically significant in patients with the hospital stay lengths longer than 10 days (RR 1.40, [1.02-1.93]; p = 0.04). Besides, SIC was significantly associated with a higher risk of 1-month mortality (RR 1.47, [1.17-1.86]; p < 0.01). Among SIC patients, right ventricular dysfunction was significantly associated with increased 1-month mortality (RR 1.72, [1.27-2.34]; p < 0.01), while left ventricular dysfunction was not (RR 1.33, [0.87-2.02]; p = 0.18).

CONCLUSIONS

With higher in-hospital mortality in those hospitalized longer than 10 days and 1-month mortality, our findings imply that SIC might continue influencing the host's system even after recovery from cardiomyopathy. Besides, right ventricular dysfunction might play a crucial role in SIC-related mortality, and timely biventricular assessment is vital in managing septic patients.

Feasibility and discriminatory value of tissue motion annular displacement in sepsis-induced cardiomyopathy: a single-center retrospective observational study

Background

There is no formal diagnostic criterion for sepsis-induced cardiomyopathy (SICM), but left ventricular ejection fraction (LVEF) < 50% was the most commonly used standard. Tissue motion annular displacement (TMAD) is a novel speckle tracking indicator to quickly assess LV longitudinal systolic function. This study aimed to evaluate the feasibility and discriminatory value of TMAD for predicting SICM, as well as prognostic value of TMAD for mortality.

Methods

We conducted a single-center retrospective observational study in patients with sepsis or septic shock who underwent echocardiography examination within the first 24 h after admission. Basic clinical information and conventional echocardiographic data, including mitral annular plane systolic excursion (MAPSE), were collected. Based on speckle tracking echocardiography (STE), global longitudinal strain (GLS) and TMAD were, respectively, performed offline. The parameters acquisition rate, inter- and intra-observer reliability, time consumed for measurement were assessed for the feasibility analysis. Areas under the receiver operating characteristic curves (AUROC) values were calculated to assess the discriminatory value of TMAD/GLS/MAPSE for predicting SICM, defined as LVEF < 50%. Kaplan–Meier survival curve analysis was performed according to the cutoff values in predicting SICM. Cox proportional hazards model was performed to determine the risk factors for 28d and in-hospital mortality.

Results

A total of 143 patients were enrolled in this study. Compared with LVEF, GLS or MAPSE, TMAD exhibited the highest parameter acquisition rate, intra- and inter-observer reliability. The mean time for offline analyses with TMAD was significantly shorter than that with LVEF or GLS (p < 0.05). According to the AUROC analysis, TMADMid presented an excellent discriminatory value for predicting SICM (AUROC > 0.9). Patients with lower TMADMid (< 9.75 mm) had significantly higher 28d and in-hospital mortality (both p < 0.05). The multivariate Cox proportional hazards model revealed that BMI and SOFA were the independent risk factors for 28d and in-hospital mortality in sepsis cases, but TMAD was not.

Conclusion

STE-based TMAD is a novel and feasible technology with promising discriminatory value for predicting SICM with LVEF < 50%.

A case of sepsis-induced cardiomyopathy successfully treated with venoarterial extracorporeal membrane oxygenation

Introduction

Sepsis with concomitant acute pyelonephritis, secondary to urolithiasis, is common. We report a case of sepsis-induced cardiomyopathy with acute pyelonephritis, successfully managed with venoarterial extracorporeal membrane oxygenation.

Case presentation

A 64-year-old woman presented with fever and disturbed consciousness. Abdominal computed tomography revealed right hydronephrosis with ipsilateral ureteral stone. Despite ureteral stent placement and antibiotic treatment, her hemodynamics worsened. She was diagnosed with sepsis-induced cardiomyopathy and underwent venoarterial extracorporeal membrane oxygenation. Her hemodynamics improved rapidly; venoarterial extracorporeal membrane oxygenation was withdrawn on postoperative day-3. She was discharged from our hospital after sufficient antibiotic treatment.

Conclusion

Venoarterial extracorporeal membrane oxygenation may be initiated in patients with sepsis-induced cardiomyopathy. Evaluation of left ventricular ejection fraction via echocardiography is important to determine the indication for venoarterial extracorporeal membrane oxygenation.

Protein Phosphatase 2A Improves Cardiac Functional Response to Ischemia and Sepsis

Reversible protein phosphorylation is a posttranslational modification of regulatory proteins involved in cardiac signaling pathways. Here, we focus on the role of protein phosphatase 2A (PP2A) for cardiac gene expression and stress response using a transgenic mouse model with cardiac myocyte-specific overexpression of the catalytic subunit of PP2A (PP2A-TG). Gene and protein expression were assessed under basal conditions by gene chip analysis and Western blotting. Some cardiac genes related to the cell metabolism and to protein phosphorylation such as kinases and phosphatases were altered in PP2A-TG compared to wild type mice (WT). As cardiac stressors, a lipopolysaccharide (LPS)-induced sepsis in vivo and a global cardiac ischemia in vitro (stop-flow isolated perfused heart model) were examined. Whereas the basal cardiac function was reduced in PP2A-TG as studied by echocardiography or as studied in the isolated work-performing heart, the acute LPS- or ischemia-induced cardiac dysfunction deteriorated less in PP2A-TG compared to WT. From the data, we conclude that increased PP2A activity may influence the acute stress tolerance of cardiac myocytes.