Persistent preload defect in severe sepsis despite fluid loading: A longitudinal echocardiographic study in patients with septic shock

Sepsis-associated endothelial glycocalyx damage: a review of animal models, clinical evidence, and molecular mechanisms

In the mammalian cardiovascular system, endothelial glycocalyx is a gel-like layer that covers the luminal surface of endothelial cells (ECs) and plays crucial roles in vascular homeostasis, permeability and leukocyte adhesion. Degradation of this structure occurs early in sepsis and becomes accordingly dysfunctional. In severe cases, it is not self-regulated by the organism. However, the relationship between the glycocalyx and the occurrence and development of sepsis remains poorly understood. One possibility is that thinned glycocalyx promotes leukocyte recognition and adhesion, thereby facilitating the elimination of pathogens from infected areas. This may represent a protective mechanism developed by the organism during through evolutionary processes. However, if the damage persists and disrupts the dynamic balance of the microcirculation, interstitial edema or organ failure can occur. Thus, we asked the questions, what is the precise composition and structure of the glycocalyx? How is it degraded? What animal models are available to study the relationship between the glycocalyx and sepsis? What glycocalyx biomarkers are found in the blood of patients with sepsis? To determine whether sepsis can be treated by interfering with the glycocalyx, this study provides a systematic summary and discussion of the latest progress in addressing these questions.

Septic Cardiomyopathy: Difficult Definition, Challenging Diagnosis, Unclear Treatment

Sepsis is a systemic inflammatory response syndrome of suspected or confirmed infectious origin, which frequently culminates in multiorgan failure, including cardiac involvement. Septic cardiomyopathy (SCM) remains a poorly defined clinical entity, lacking a formal or consensus definition and representing a significant knowledge gap in critical care medicine. It is an often-underdiagnosed complication of sepsis. The only widely accepted aspect of its definition is that SCM is a transient myocardial dysfunction occurring in patients with sepsis, which cannot be attributed to ischemia or pre-existing cardiac disease. The pathogenesis of SCM appears to be multifactorial, involving inflammatory cytokines, overproduction of nitric oxide, mitochondrial dysfunction, calcium homeostasis dysregulation, autonomic imbalance, and myocardial edema. Diagnosis primarily relies on echocardiography, with advanced tools such as tissue Doppler imaging (TDI) and global longitudinal strain (GLS) providing greater sensitivity for detecting subclinical dysfunction and guiding therapeutic decisions. Traditional echocardiographic findings, such as left ventricular ejection fraction measured by 2D echocardiography, often reflect systemic vasoplegia rather than intrinsic myocardial dysfunction, complicating accurate diagnosis. Right ventricular (RV) dysfunction, identified as a critical component of SCM in many studies, has multifactorial pathophysiology. Factors including septic cardiomyopathy itself, mechanical ventilation, hypoxemia, and hypercapnia-particularly in cases complicated by acute respiratory distress syndrome (ARDS)-increase RV afterload and exacerbate RV dysfunction. The prognostic value of cardiac biomarkers, such as troponins and natriuretic peptides, remains uncertain, as these markers primarily reflect illness severity rather than being specific to SCM. Treatment focuses on the early recognition of sepsis, hemodynamic optimization, and etiological interventions, as no targeted therapies currently exist. Emerging therapies, such as levosimendan and VA-ECMO, show potential in severe SCM cases, though further validation is needed. The lack of standardized diagnostic criteria, combined with the heterogeneity of sepsis presentations, poses significant challenges to the effective management of SCM. Future research should focus on developing cluster-based classification systems for septic shock patients by integrating biomarkers, echocardiographic findings, and clinical parameters. These advancements could clarify the underlying pathophysiology and enable tailored therapeutic strategies to improve outcomes for SCM patients.

A murine model of acute and prolonged abdominal sepsis, supported by intensive care, reveals time-dependent metabolic alterations in the heart

BACKGROUND

Sepsis-induced cardiomyopathy (SICM) often occurs in the acute phase of sepsis and is associated with increased mortality due to cardiac dysfunction. The pathogenesis remains poorly understood, and no specific treatments are available. Although SICM is considered reversible, emerging evidence suggests potential long-term sequelae. We hypothesized that metabolic and inflammatory cardiac changes, previously observed in acute sepsis as potential drivers of SICM, partially persist in prolonged sepsis.

METHODS

In 24-week-old C57BL/6J mice, sepsis was induced by cecal ligation and puncture, followed by intravenous fluid resuscitation, subcutaneous analgesics and antibiotics, and, in the prolonged phase, by parenteral nutrition. Mice were killed after 5 days of sepsis (prolonged sepsis, n = 15). For comparison, we included acutely septic mice killed at 30 h (acute sepsis, n = 15) and healthy controls animals (HC, n = 15). Cardiac tissue was collected for assessment of inflammatory and metabolic markers through gene expression, metabolomic analysis and histological assessment.

RESULTS

In prolonged sepsis, cardiac expression of IL-1β and IL-6 and macrophage infiltration remained upregulated (p ≤ 0.05). In contrast, tissue levels of Krebs cycle intermediates and adenosine phosphates were normal, whereas NADPH levels were low in prolonged sepsis (p ≤ 0.05). Gene expression of fatty acid transporters and of the glucose transporter Slc2a1 was upregulated in prolonged sepsis (p ≤ 0.01). Lipid staining and glycogen content were elevated in prolonged sepsis together with increased gene expression of enzymes responsible for lipogenesis and glycogen synthesis (p ≤ 0.05). Intermediate glycolytic metabolites (hexose-phosphates, GADP, DHAP) were elevated (p ≤ 0.05), but gene expression of several enzymes for glycolysis and mitochondrial oxidation of pyruvate, fatty-acyl-CoA and ketone bodies to acetyl-CoA were suppressed in prolonged sepsis (p ≤ 0.05). Key metabolic transcription factors PPARα and PGC-1α were downregulated in acute, but upregulated in prolonged, sepsis (p ≤ 0.05 for both). Ketone body concentrations were normal but ketolytic enzymes remained suppressed (p ≤ 0.05). Amino acid metabolism showed mild, mixed changes.

CONCLUSIONS

Our results suggest myocardial lipid and glycogen accumulation and suppressed mitochondrial oxidation, with a functionally intact Krebs cycle, in the prolonged phase of sepsis, together with ongoing myocardial inflammation. Whether these alterations have functional consequences and predispose to long-term sequelae of SICM needs further research.

Ferrostatin-1 improves acute sepsis-induced cardiomyopathy via inhibiting neutrophil infiltration through impaired chemokine axis

Introduction

Sepsis-induced cardiomyopathy is a common complication of sepsis and is associated with higher mortality. To date, effective diagnostic and management strategies are still lacking. Recent studies suggest that ferroptosis plays a critical role in sepsis-induced cardiomyopathy and ferroptosis inhibitor Ferrostatin-1 (Fer-1) improved cardiac dysfunction and survival in lipopolysaccharide (LPS) induced endotoxemia. However, the effects of Fer-1 in cardiac dysfunction in the early stages of cecal ligation and puncture (CLP) induced sepsis remains unclear. Our study aims to elucidate the role of Fer-1 in the acute phase of peritonitis sepsis induced cardiac injury.

Methods and Results

CLP was used to induce peritonitis sepsis in mice. Pretreatment of ferroptosis inhibitor ferrostatin-1 (Fer-1) was used in the in vivo models. Survival was monitored for 48h. Cardiac function and histology were analyzed 6h after surgery. We found that ejection fraction (EF) remained normal at 6h after CLP, but the contractility detected by cardiac muscle strain analysis was significantly reduced, along with increased immune cell infiltration. Pretreating the CLP mice with 5 mg/kg Fer-1 significantly reduced mortality. At 6h after CLP, ferroptosis key regulator Gpx4, cardiac iron and malonaldehyde (MDA) did not change, but ferroptosis marker gene expression increased. Fer-1 treatment showed beneficial effects in cardiac function, less myocardial inflammatory cytokine expression and significantly inhibited immune cells, especially neutrophil infiltration in the heart. Consistently, expression of neutrophil associated chemokines (Ccrl2, Cxcl2, Cxcl3 and Cxcl5) as well as extracellular matrix (ECM) degradation enzymes (Adamts1, Adamts4, Adamts9 and Mmp8) significantly decreased in Fer-1 pre-treated CLP heart.

Conclusion and Discussion

Our findings suggest that Fer-1 inhibits neutrophil infiltration in early sepsis by disrupting the chemokine axis, highlighting its potential as a therapeutic option to manage acute immune overactivation in early stages of sepsis-induced cardiomyopathy.

Sepsis-Induced Cardiomyopathy Secondary to Escherichia coli Sepsis and Intestinal Perforation: A Diagnostic Challenge in a Paediatric Patient

A five-year-old male presented with abdominal pain, fever, vomiting, and constipation. Initial investigations suggested subacute intestinal obstruction. Laparotomy revealed intestinal perforation with peritonitis due to Escherichia coli. Post-operatively, the patient developed sepsis-induced cardiomyopathy (SICM), requiring inotropic support and mechanical ventilation. The complex clinical presentation and overlap of symptoms with septic shock delayed the diagnosis of SICM, making timely identification challenging. This case highlights the diagnostic challenges in identifying sepsis-induced cardiomyopathy in the context of severe sepsis and abdominal pathology, underscoring the need for early recognition, particularly using echocardiography for myocardial dysfunction assessment.

From Kidney Crisis to Heart Revival: A Case of Septic Cardiomyopathy Following Septic Shock Induced by Xanthogranulomatous Pyelonephritis

Septic cardiomyopathy (SCM) is a reversible cardiac dysfunction occurring in patients with sepsis or septic shock, characterized by transient impaired myocardial contractility. Despite its prevalence in severe sepsis and significant impact on patient outcomes, SCM remains underdiagnosed and is one of the least studied forms of cardiomyopathy. Its recognition and management are further complicated by the absence of a universally accepted consensus on its diagnostic criteria and definition. We report the case of a 54-year-old female presenting with septic shock secondary to xanthogranulomatous pyelonephritis (XGP). The patient presented with acute right lower back pain, fever, and hemodynamic instability. Initial echocardiography assessment demonstrated a preserved left ventricular ejection fraction (LVEF), which subsequently deteriorated following the onset of septic cardiomyopathy. Early recognition and management, including the use of vasopressors, inotropes, and judicious fluid resuscitation, resulted in full recovery of cardiac function within one week. This case highlights the importance of clinical vigilance and prompt intervention in the management of SCM, particularly in cases complicating severe infections such as XGP.

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.

How to use echocardiography to manage patients with shock?

Echocardiography enables the intensivist to assess the patient with circulatory failure. It allows the clinician to identify rapidly the type and the cause of shock in order to develop an effective management strategy. Important characteristics in the setting of shock are that it is non-invasive and can be rapidly applied. Early and repeated echocardiography is a valuable tool for the management of shock in the intensive care unit. Competency in basic critical care echocardiography is now regarded as a mandatory part of critical care training with clear guidelines available. The majority of pathologies found in shocked patients are readily identified using basic level 2D and M-mode echocardiography. The four core types of shock (cardiogenic, hypovolemic, obstructive, and septic) can readily be identified by echocardiography. Echocardiography can differentiate the different pathologies that may be the cause of each type of shock. More importantly, as a result of more complex and elderly patients, the shock may be multifactorial, such as a combination of cardiogenic and septic shock, which emphasises on the added value of transthoracic echocardiography (TTE) in such population of patients. In this review we aimed to provide to clinicians a bedside strategy of the use of TTE parameters to manage patients with shock. In the first part of this overview, we detailed the different TTE parameters and how to use them to identify the type of shock. And in the second part, we focused on the use of these parameters to evaluate the effect of treatments, in different types of shock.

Physiological changes after fluid bolus therapy in cardiac surgery patients: A propensity score matched case-control study

Objective

Fluid bolus therapy (FBT) is ubiquitous in intensive care units (ICUs) after cardiac surgery. However, its physiological effects remain unclear.

Design

: We performed an electronic health record-based quasi-experimental ICU study after cardiac surgery. We applied propensity score matching and compared the physiological changes after FBT episodes to matched control episodes where despite equivalent physiology no fluid bolus was given.

Setting

The study was conducted in a multidisciplinary ICU of a tertiary-level academic hospital.

Participants

The study included 2,736 patients who underwent Coronary Artery Bypass Grafting and/or heart valve surgery.

Main Outcome Measures

Changes in cardiac output (CO) and mean arterial pressure (MAP) during the 60 minutes following FBT.

Results

We analysed 3572 matched fluid bolus (FB) episodes. After FBT, but not in control episodes, CO increased within 10 min, with a maximum increase of 0.2 l/min (95%CI 0.1 to 0.2) or 4% above baseline at 40 min (p < 0.0001 vs. controls). CO increased by > 10% from baseline in 60.6% of FBT and 49.1% of control episodes (p < 0.0001). MAP increased by > 10% in 51.7% of FB episodes compared to 53.4% of controls. Finally, FBT was not associated with changes in acid-base status or oxygen delivery.

Conclusion

In this quasi-experimental comparative ICU study in cardiac surgery patients, FBT was associated with statistically significant but numerically small increases in CO. Nearly half of FBT failed to induce a positive CO or MAP response.

Prognostic value of right ventricular free wall strain in patients with sepsis

Background

Right ventricular systolic dysfunction (RVSD) in patients with sepsis is an area of growing interest, but its prognostic significance remains unclear and additional tools are needed to improve our understanding. Right ventricular free wall strain (RV-FWS) is a relatively new parameter to assess RV function. This study aimed to investigate the potential correlation between impaired RV-FWS and prognostic outcomes in patients with sepsis.

Methods

We prospectively assessed right ventricular function in patients with sepsis within the initial 24 h of their hospital admission. RV-FWS, right ventricular global strain (RV-GS), fractional area change (FAC), and tricuspid annular plane systolic excursion (TAPSE) were examined. RVSD was defined as impaired RV-FWS. Moreover, the association between RVSD and 30-day mortality rate was assessed.

Results

This study included 89 patients. Among them, 27 (30.3%) succumbed to their illness within 30 days. The nonsurviving patients demonstrated significantly lower absolute RV-FWS (-19.7% ± 2.4% vs. -21.1% ± 2.1%, P = 0.008) and RV-GS (-17.7% ± 1.2% vs. -18.4% ± 1.4%, P = 0.032) values than the surviving patients. However, TAPSE and FAC values were not significantly different between the two groups. The optimal cutoff values for RV-FWS, RV-GS, FAC, and TAPSE were -19.0%, -17.9%, 36.5%, and 1.55 cm, respectively. Kaplan-Meier survival curves revealed that patients with impaired RV-FWS and RV-GS demonstrated lower 30-day survival rates, and the predictive performance of RV-FWS (hazard ratio [HR]: 3.97, 95% confidence interval [CI]: 1.85-8.51, P < 0.001) was slightly higher than FAC and TAPSE. However, multivariable Cox regression analysis revealed no association between impaired RV-FWS and mortality outcomes (HR: 1.85, 95% CI: 0.56-6.14, P = 0.316).

Conclusions

Impaired RV-FWS is not associated with short-term mortality outcomes, and RV strain imaging is of limited value in assessing the prognosis of sepsis.

Cardiac Magnetic Resonance Studies in a Large Animal Model that Simulates the Cardiac Abnormalities of Human Septic Shock

Background

Septic shock, in humans and in our well-established animal model, is associated with increases in biventricular end diastolic volume (EDV) and decreases in ejection fraction (EF). These abnormalities occur over 2 days and reverse within 10 days. Septic non-survivors do not develop an increase in EDV. The mechanism for this cardiac dysfunction and EDV differences is unknown.

Methods

Purpose-bred beagles randomized to receive intrabronchial Staphylococcus aureus (n=27) or saline (n=6) were provided standard ICU care including sedation, mechanical ventilation, and fluid resuscitation to a pulmonary arterial occlusion pressure of over 10mmHg. No catecholamines were administered. Over 96h, cardiac magnetic resonance imaging, echocardiograms, and invasive hemodynamics were serially performed, and laboratory data was collected. Tissue was obtained at 66h from six septic animals.

Results

From 0-96h after bacterial challenge, septic animals vs. controls had significantly increased left ventricular wall edema (6%) and wall thinning with loss of mass (15%) which was more pronounced at 48h in non-survivors than survivors. On histology, edema was located predominantly in myocytes, the interstitium, and endothelial cells. Edema was associated with significantly worse biventricular function (lower EFs), ventricular-arterial coupling, and circumferential strain. In septic animals, from 0-24h, the EDV decreased from baseline and, despite cardiac filling pressures being similar, decreased significantly more in non-survivors. From 24-48h, all septic animals had increases in biventricular chamber sizes. Survivors biventricular EDVs were significantly greater than baseline and in non-survivors, where biventricular EDVs were not different from baseline. Preload, afterload, or HR differences did not explain these differential serial changes in chamber size.

Conclusion

Systolic and diastolic cardiac dysfunction during sepsis is associated with ventricular wall edema. Rather than differences in preload, afterload, or heart rate, structural alterations to the ventricular wall best account for the volume changes associated with outcome during sepsis. In non-survivors, from 0-24h, sepsis induces a more severe diastolic dysfunction, further decreasing chamber size. The loss of left ventricular mass with wall thinning in septic survivors may, in part explain, the EDV increases from 24-48h. However, these changes continued and even accelerated into the recovery phase consistent with a reparative process rather than ongoing injury.

Clinical implications of endotoxin activity and Polymyxin-B hemoperfusion in critically ill patients with septic cardiomyopathy: A single-center, retrospective, observational study

BACKGROUND

To explore the association between endotoxin activity (EA) and septic cardiomyopathy (SCM), the relationship between endotoxin removal by Polymyxin-B hemoperfusion (PMX-HP) and recovery from SCM (R-SCM), and the correlation between R-SCM and the 28-day mortality in septic patients admitted to the intensive care unit (ICU).

METHODS

Observational study that included patients admitted to two ICUs of a tertiary university hospital between April 2011 and December 2019, who received PMX-HP for sepsis/septic shock. The SCM and R-SCM were assessed by transthoracic echocardiography.

RESULTS

Among 148 patients, SCM was diagnosed in 60 (46%) of them and had no relationship with median EA (SCM group: 0.73; no-SCM group: 0.66, p = 0.48). Recovery from SCM was observed in 24 patients (49%) and was independently associated with the PMX-HP (OR 4.19, 95%CI [1.22, 14.3]; p = 0.02) and the SAPS2 II score (OR 0.94, 95%CI [0.9, 0.98]; p = 0.006). In the SCM group, the 28-day mortality was 60% and was independently predicted by R-SCM (OR 0.02, 95%CI [0.001, 0.3] p = 0.005) and SAPS II score (OR 1.11, 95%CI [1.01, 1.23] p = 0.037).

CONCLUSIONS

In septic patients, EA was not associated with SCM. However, endotoxin removal by Polymyxin-B hemoperfusion was associated with recovery from cardiomyopathy, which was a predictor of lower 28-day mortality.

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.

METTL3 achieves lipopolysaccharide-induced myocardial injury via m6A-dependent stabilization of Myh3 mRNA

Septic cardiomyopathy (SCM) was an important pathological component of severe sepsis and septic shock. N6-methyladenosine (m6A) modification was a common RNA modification in both mRNA and non-coding RNAs and was proved to be involved in sepsis and immune disorders. Therefore, the purpose of this study was to investigate the role and mechanism of METTL3 in lipopolysaccharide-induced myocardial injury. We firstly analyzed the expression changes of various m6A-related regulators in human samples in the GSE79962 data and the Receiver Operating Characteristic curve of significantly changed m6A enzymes, showing that METTL3 had a high diagnostic ability in patients with SCM. Western blotting confirmed the high expression of METTL3 in LPS-treated H9C2 cells, which was consistent with the above results in human samples. In vitro and in vivo, the deficiency of METTL3 could improve the cardiac function, cardiac tissue damage, myocardial cell apoptosis and reactive oxygen species levels in LPS-treated H9C2 cells and LPS-induced sepsis rats, respectively. In addition, we obtained 213 differential genes through transcriptome RNA-seq analysis, and conducted GO enrichment analysis and KEGG pathway analysis through DAVID. We also found that the half-life of Myh3 mRNA was significantly reduced after METTL3 deletion and that Myh3 carried several potential m6A modification sites. In conclusion, we found that downregulation of METTL3 reversed LPS-induced myocardial cell and tissue damage and reduced cardiac function, mainly by increasing Myh3 stability. Our study revealed a key role of METTL3-mediated m6A methylation in septic cardiomyopathy, which may offer a potential mechanism for the therapy of septic cardiomyopathy.

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.

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.

Septic cardiomyopathy: characteristics, evaluation, and mechanism

Sepsis is a common clinical disease; if there is no early active treatment, it is likely to develop into multiple organ dysfunction syndrome and even cause death. Septic cardiomyopathy is a complication of sepsis-related cardiovascular failure, characterized by reversible left ventricular dilatation and decreased ventricular systolic and/or diastolic function. At present, echocardiography and biomarkers are often used to screen septic cardiomyopathy in clinics. Although there is still a lack of clear diagnostic criteria for septic cardiomyopathy, according to existing studies, the pathogenesis of several septic cardiomyopathy has been clarified, such as immune response caused by infection and mitochondrial dysfunction. This review summarizes the characteristics, pathophysiology, and diagnosis of septic cardiomyopathy and focuses on the mechanisms of infection immunity and mitochondrial dysfunction.

A multicenter prospective cohort study of cardiac ultrasound phenotypes in patients with sepsis: Study protocol for a multicenter prospective cohort trial

Background

Sepsis-induced cardiomyopathy significantly increased the mortality of patients with sepsis. The diagnostic criteria for septic cardiomyopathy has not been unified, which brings serious difficulties to clinical treatment. This study aimed to provide evidence for the early identification and intervention in patients with sepsis by clarifying the relationship between the ultrasound phenotype of septic cardiomyopathy and the prognosis of patients with sepsis.

Methods

This was a multicenter, prospective cohort study. The study population will consist of all eligible consecutive patients with sepsis or septic shock who meet the Sepsis 3.0 diagnostic criteria and were aged ≥18 years. Clinical data and echocardiographic measurements will be recorded within 2 h, at the 24th hour, at the 72nd hour, and on the 7th day after admission. The prevalence of each phenotype will be described as well, and their association with prognosis will be analyzed statistically.

Discussion

To achieve early recognition, prevent reinjury, achieve precise treatment, and reduce mortality in patients with sepsis, it is important to identify septic cardiac alterations and classify the phenotypes at all stages of sepsis. First, there is a lack of studies on the prevalence of each phenotype in Chinese populations. Second, each phenotype and its corresponding prognosis are not clear. In addition, the prognosis of patients with normal cardiac ultrasound phenotypes vs. those with suppressed or hyperdynamic cardiac phenotypes is unclear. Finally, this study was designed to collect data at four specific timing, then the timing of occurrence, duration, changes over time, impact to outcomes of each phenotype will probably be found. This study is expected to establish a standard and objective method to assess the ultrasound phenotype of septic cardiomyopathy due to its advantages of visualization, non-invasiveness and reproducibility, and to provide more precise information for the hemodynamic management of septic patients. In addition, this research will promote the clinical application of critical care ultrasound, which will play an important role in medical education and make ultrasound the best method to assess cardiac changes in sepsis.

Trial registration

https://clinicaltrials.gov/ct2/show/NCT05161104, identifier NCT05161104.

Septic cardiomyopathy: Diagnosis and management

There is an extensive body of literature focused on sepsis-induced myocardial dysfunction, but results are conflicting and no objective definition of septic cardiomyopathy (SCM) has been established. SCM may be defined as a sepsis-associated acute syndrome of non-ischemic cardiac dysfunction with systolic and/or diastolic left ventricular (LV) dysfunction and/or right ventricular dysfunction. Physicians should consider this diagnosis in patients with sepsis-associated organ dysfunction, and particularly in cases of septic shock that require vasopressors. Echocardiography is currently the gold standard for diagnosis of SCM. Left ventricular ejection fraction is the most common parameter used to describe LV function in the literature, but its dependence on loading conditions, particularly afterload, limits its use as a measure of intrinsic myocardial contractility. Therefore, repeated echocardiography evaluation is mandatory. Evaluation of global longitudinal strain (GLS) may be more sensitive and specific for SCM than LV ejection fraction (LVEF). Standard management includes etiological treatment, adapted fluid resuscitation, use of vasopressors, and monitoring. Use of inotropes remains uncertain, and heart rate control could be an option in some patients.

Incidence, prognosis, and risk factors of sepsis-induced cardiomyopathy

BACKGROUND

At present, large-scale studies on the clinical characteristics of sepsis-induced cardiomyopathy (SIC) are lacking.

AIM

To investigate the clinical characteristics of SIC.

METHODS

Based on the analysis of the MIMIC-III public database, we performed a large-scale retrospective study involving sepsis patients who were admitted to the intensive care unit (ICU) and had no concomitant cardiac disease. We used propensity score matching analysis and multivariate logistic regression to ensure the robustness of the results. The primary outcome was hospital mortality, and the secondary outcomes included the number of patients who received mechanical ventilation or renal replacement therapy during their hospital stay, the number of patients administered with vasopressors, the length of ICU stay, and the length of hospital stay.

RESULTS

In the present study, after screening 38605 patients, 3530 patients with sepsis were included. A total of 997 patients met the SIC diagnostic criteria, and the incidence of SIC was 28.20% (95% confidence interval [CI]: 26.80%-29.70%). Compared to patients in the non-SIC group, patients in the SIC group were of older age and had a higher Simplified Acute Physiology Score (SAPS)-I score, SAPS-II score, and Elixhauser comorbidity index (ECI). A total of 367 (36.8%) of 997 patients in the SIC group and 818 (32.3%) of 2533 patients in the non-SIC group died in the hospital, which resulted in a significant between-group difference (odds ratios = 1.22, 95%CI: 1.05-1.42; P = 0.011). For the secondary outcomes, more patients in the SIC group received mechanical ventilation and vasopressors. Multivariate logistic regression analysis showed that age, male sex, ECI, hemoglobin level, diabetes, and mechanical ventilation use on the first day of ICU admission were risk factors for SIC.

CONCLUSION

Compared with non-SIC patients, hospital mortality is higher in SIC patients.

The Urosepsis-A Literature Review

Urosepsis is a very serious condition with a high mortality rate. The immune response is in the center of pathophysiology. The therapeutic management of these patients includes surgical treatment of the source of infection, antibiotic therapy and life support. The management of this pathology is multidisciplinary and requires good collaboration between the urology, intensive care, imaging and laboratory medicine departments. An imbalance of pro and anti-inflammatory cytokines produced during sepsis plays an important role in pathogenesis. The study of cytokines in sepsis has important implications for understanding pathophysiology and for development of other therapeutic solutions. If not treated adequately, urosepsis may lead to serious septic complications and organ sequelae, even to a lethal outcome.

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

Background

Patients with sepsis are at risk for developing sepsis-induced cardiomyopathy (SIC). Previous studies offer inconsistent results regarding the association of SIC and mortality. This study sought to assess whether SIC is linked to mortality in patients with sepsis and to evaluate predictors of the development of SIC.

Methods

In this retrospective study, patients admitted to the medical intensive care unit with a diagnosis of sepsis in the absence of acute coronary syndrome were included. SIC was identified using transthoracic echo and was defined by a new onset decline in left ventricular ejection fraction (LVEF) ≤50%, or ≥10% decline in LVEF compared to baseline in patients with a history of heart failure with reduced ejection fraction. Multivariable logistic regression analysis was performed using the R software program.

Results

Of the 359 patients in the final analysis, 19 (5.3%) had SIC. Eight (42.1%) of the 19 patients in the SIC group and 60 (17.6%) of the 340 patients in the non-SIC group died during hospitalization. SIC was associated with an increased risk for all-cause in-hospital mortality (odds ratio [OR], 4.46; 95% confidence interval [CI], 1.15–18.69; P=0.03). Independent predictors for the development of SIC were albumin level (OR, 0.47; 95% CI, 0.23–0.93; P=0.03) and culture positivity (OR, 8.47; 95% CI, 2.24–55.61; P=0.006). Concomitant right ventricular hypokinesis was noted in 13 (68.4%) of the 19 SIC patients.

Conclusions

SIC was associated with an increased risk for all-cause in-hospital mortality. Low albumin level and culture positivity were independent predictors of SIC.

Echocardiographic Assessment of Left Ventricular Systolic and Diastolic Functions in Dogs with Severe Sepsis and Septic Shock; Longitudinal Study

Simple Summary

Sepsis is associated with cardiovascular changes. The aim of the study was to determine sepsis-induced myocardial dysfunction in dogs with severe sepsis and septic shock using transthoracic echocardiography. Clinical, laboratory and cardiologic examinations for the septic dogs were performed at admission, 6 and 24 h, and on the day of discharge from the hospital. Left ventricular (LV) systolic dysfunction, LV diastolic dysfunction, and both types of the dysfunction were present in 13%, 70%, and 9% of dogs with sepsis, respectively. Dogs with LV diastolic dysfunction had a worse outcome and short-term mortality. Transthoracic echocardiography can be used for monitoring cardiovascular dysfunction in dogs with sepsis.

Abstract

The purpose of this study was to monitor left ventricular systolic dysfunction (LVSD) and diastolic dysfunction (LVDD) using transthoracic echocardiography (TTE) in dogs with severe sepsis and septic shock (SS/SS). A prospective longitudinal study using 23 dogs with SS/SS (experimental group) and 20 healthy dogs (control group) were carried out. All the clinical, laboratory and cardiologic examinations for the experimental dogs were performed at admission, 6 and 24 h after the start of treatment and on the day of discharge. LVSD was described as LV ejection fraction (LVEF) < 50%. LVDD was determined when the septal mitral annulus early diastolic velocity (LVEm) was <8 cm/s. LVSD and LVDD were present in 3 and 16 dogs with SS/SS, respectively, with both types of dysfunction present in 2 of the dogs. Although all the dogs with LVSD survived, 8 dogs with LVDD did not. The survival period was significantly shorter in dogs with an LVEm < 8 cm/s (1.3 ± 1.4 days). In conclusion, LVDD, rather than LVSD, was a common cardiovascular abnormality in the septic dogs, and this may be a negative prognostic factor. TTE is a useful tool for the identifying and monitoring of myocardial dysfunction in the dogs with SS/SS.

Wnt/β-Catenin Antagonist Pyrvinium Exerts Cardioprotective Effects in Polymicrobial Sepsis Model by Attenuating Calcium Dyshomeostasis and Mitochondrial Dysfunction

Calcium dysregulation and mitochondrial dysfunction are key elements in the development of sepsis-induced cardiac dysfunction. Evidences have suggested that inhibition of Wnt/β-Catenin signalling prevents cardiac dysfunction and remodelling in surgical, hypertension and pressure overload models. The present study investigated the effects of Wnt/β-Catenin inhibitor on calcium overload and mitochondrial dysfunction in rat sepsis model of cardiomyopathy. Induction of sepsis by cecal ligation puncture (CLP) resulted in the up-regulation of cardiac β-catenin transcriptional levels and cardiac dysfunction depicted by increased serum lactate dehydrogenase, CK-MB levels reduced maximum (dp/dt max.) and minimum developed pressure (dp/dt min.), increased LVEsDP and relaxation constant tau values. Moreover, oxidative and inflammatory stress, immune cell infiltration, increased myeloperoxidase activity, enhanced caspase-3 activity and fibronectin protein levels were observed in septic rat's heart. Also, septic rat's heart displayed mitochondrial dysfunction due to mPTP opening, increased calcium up-regulation in left ventricular apex tissues and whole heart, increased collagen staining, necrosis and structural damage. Pre-treatment with Wnt/β-Catenin antagonist attenuated sepsis-induced serum and tissue biochemical changes, cardiac dysfunction and structural alterations by inhibiting mitochondrial mPTP opening and restricting calcium overloading in cardiac tissue.

Multi-biomarker strategy for prediction of myocardial dysfunction and mortality in sepsis

OBJECTIVE

The present study was to evaluate the feasibility of using the multi-biomarker strategy for the prediction of sepsis-induced myocardial dysfunction (SIMD) and mortality in septic patients.

METHODS

Brain natriuretic peptide (BNP), cardiac troponin I (cTnI), and heart-type fatty acid-binding protein (h-FABP) in 147 septic patients were assayed within 6 h after admission. We also determined the plasma levels of myeloperoxidase (MPO) and pregnancy-associated plasma protein-A (PAPP-A). The receiver operating characteristic (ROC) curve was used to assess the best cutoff values of various single-biomarkers for the diagnosis of SIMD and the prediction of mortality. Also, the ROC curve, net reclassification improvement (NRI), and integrated discrimination improvement (IDI) indices were used to evaluate the feasibility of using multi-biomarkers to predict SIMD and mortality.

RESULTS

Our statistics revealed that only h-FABP independently predicted SIMD (P<0.05). The addition of MPO and cTnI to h-FABP for SIMD prediction provided an NRI of 18.7% (P=0.025) and IDI of 3.3% (P=0.033). However, the addition of MPO or cTnI to h-FABP did not significantly improve the predictive ability of h-FABP to SIMD, as evidenced by the area under the curve (AUC), NRI, and IDI (all P>0.05). A history of shock and MPO were independent predictors of mortality in septic patients (both P<0.05). The addition of PAPP-A and h-FABP to MPO resulted in a mortality prediction with NRI of 25.5% (P=0.013) and IDI of 2.9% (P=0.045). However, this study revealed that the addition of h-FABP or PAPP-A to MPO did not significantly improve the ability to predict mortality, as evidenced by the AUC, NRI, and IDI (all P>0.05).

CONCLUSIONS

The findings of this study indicate that a sensitive and specific strategy for early diagnosis of SIMD and mortality prediction in sepsis should incorporate three biomarkers.

Pathophysiology of sepsis-induced cardiomyopathy

Sepsis is the life-threatening organ dysfunction caused by a dysregulated host response to infection and is the leading cause of death in intensive care units. Cardiac dysfunction caused by sepsis, usually termed sepsis-induced cardiomyopathy, is common and has long been a subject of interest. In this Review, we explore the definition, epidemiology, diagnosis and pathophysiology of septic cardiomyopathy, with an emphasis on how best to interpret this condition in the clinical context. Advances in diagnostic techniques have increased the sensitivity of detection of myocardial abnormalities but have posed challenges in linking those abnormalities to therapeutic strategies and relevant clinical outcomes. Sophisticated methodologies have elucidated various pathophysiological mechanisms but the extent to which these are adaptive responses is yet to be definitively answered. Although the indications for monitoring and treating septic cardiomyopathy are clinical and directed towards restoring tissue perfusion, a better understanding of the course and implications of septic cardiomyopathy can help to optimize interventions and improve clinical outcomes.

Hemodynamic clinical phenotyping in septic shock

PURPOSE OF REVIEW

Recent studies have failed to show significant benefit from a uniform strategy, suggesting that hemodynamic management must be individually adapted in septic shock depending on different phenotypes. Different approaches that may be used to this end will be discussed.

RECENT FINDINGS

Fluid management is a cornerstone of resuscitation, as the positive fluid balance has been associated with higher mortality and right ventricular failure. Myocardial evaluation is mandatory, as sepsis patients may present with a hyperkinetic state, left ventricular (systolic and diastolic) and/or right ventricular dysfunction, the latter being associated with higher mortality. Statistical approaches with the identification of hemodynamic clusters based on echocardiographic and clinical parameters might be integrated into daily practice to develop precision medicine. Such approaches may also predict the progression of septic shock.

SUMMARY

Different hemodynamic phenotypes can occur at any stage of sepsis and be associated with one another. The clinician must regularly assess dynamic changes in phenotypes in septic shock patients. Statistical approaches based on machine learning need to be validated by prospective studies.

Diagnostic Value of High-Sensitivity Troponin T for Subclinical Left Ventricular Systolic Dysfunction in Patients with Sepsis

Background

Left ventricular systolic dysfunction (LVSD) is common in sepsis. Speckle-tracking echocardiography (STE) is a useful emerging tool for evaluating the intrinsic left ventricular systolic function. High-sensitivity cardiac troponin T (hs-cTnT) is the most sensitive biomarker of myocardial injury. However, there are limited data regarding the association between hs-cTnT level and left ventricular systolic dysfunction based on STE in septic patients. We performed this prospective study to evaluate the diagnostic value of hs-cTnT level for subclinical left ventricular systolic dysfunction measured by STE in septic patients according to the sepsis-3 definition.

Methods

Patients with sepsis based on sepsis-3 definition admitted to the intensive care unit were prospectively performed STE and hs-cTnT level within 24 hours after the onset of sepsis. Baseline clinical and echocardiographic variables were collected. Left ventricular systolic dysfunction was defined as a global longitudinal strain of ≥−15%.

Results

During a 19-month period, 116 patients were enrolled in the study. The elevated hs-cTnT level was seen in 86.2% of septic patients, and 43.1% of patients had LVSD on STE. The median hs-cTnT level and the proportion of elevated hs-cTnT level (>14 ng/L) were significantly higher in patients with LVSD than in patients without LVSD. The area under the ROC curves of hs-cTnT to detect LVSD was 0.73 (P < 0.001). In the multivariate analysis, hs-cTnT (HR, 1.002; 95% CI, 1.000 to 1.004; P = 0.025) and septic shock (HR, 7.6; 95% CI, 2.25 to 25.76; P = 0.001) were independent predictors of LVSD.

Conclusion

Our study indicated that the serum hs-cTnT level might be a useful biomarker for detecting LVSD in septic patients.

Cardiovascular Responses During Sepsis

Sepsis is the life-threatening organ dysfunction arising from a dysregulated host response to infection. Although the specific mechanisms leading to organ dysfunction are still debated, impaired tissue oxygenation appears to play a major role, and concomitant hemodynamic alterations are invariably present. The hemodynamic phenotype of affected individuals is highly variable for reasons that have been partially elucidated. Indeed, each patient's circulatory condition is shaped by the complex interplay between the medical history, the volemic status, the interval from disease onset, the pathogen, the site of infection, and the attempted resuscitation. Moreover, the same hemodynamic pattern can be generated by different combinations of various pathophysiological processes, so the presence of a given hemodynamic pattern cannot be directly related to a unique cluster of alterations. Research based on endotoxin administration to healthy volunteers and animal models compensate, to an extent, for the scarcity of clinical studies on the evolution of sepsis hemodynamics. Their results, however, cannot be directly extrapolated to the clinical setting, due to fundamental differences between the septic patient, the healthy volunteer, and the experimental model. Numerous microcirculatory derangements might exist in the septic host, even in the presence of a preserved macrocirculation. This dissociation between the macro- and the microcirculation might account for the limited success of therapeutic interventions targeting typical hemodynamic parameters, such as arterial and cardiac filling pressures, and cardiac output. Finally, physiological studies point to an early contribution of cardiac dysfunction to the septic phenotype, however, our defective diagnostic tools preclude its clinical recognition. © 2021 American Physiological Society. Compr Physiol 11:1605-1652, 2021.

Prognostic stratification in septic patients with overt and cryptic shock by speckle tracking echocardiography

We evaluated the prevalence and prognostic value of left (LV) and right (RV) ventricular systolic dysfunction in the presence of overt and cryptic shock. In this prospective study, between October 2012 and June 2019, we enrolled 354 patients with sepsis, 41% with shock, among those admitted to the Emergency Department High-Dependency Unit. Patients were grouped based on the presence of shock, or by the presence of lactate levels ≥ (LAC +) or < 2 mmol/L (LAC-) evaluated within the first 24 h. By echocardiography performed within 24 h from the admission, LV systolic dysfunction was defined as global longitudinal strain (GLS) > -14%; RV systolic dysfunction as Tricuspid Annular Plane Systolic Excursion (TAPSE) < 16 mm. All-cause mortality was assessed at day-7 and day-28 follow-up. Mean values of LV GLS (-12.3 ± 3.4 vs -12.9 ± 3.8%) and TAPSE (1.8 ± 0.7 vs 1.8 ± 0.5 cm, all p = NS) were similar in patients with and in those without shock. LV GLS was significantly worse in LAC + than LAC- patients (- 11.2 ± 3.1 vs - 12.9 ± 3.7%, p = 0.001). In patients without shock, as well as in those LAC-, LV dysfunction was associated with increased day-28 mortality rate (78% vs 57% in non-survivors and survivors without shock and 74% vs 53% in non-survivors and survivors LAC-, all p < 0.01). LV (RR 2.26, 95% CI 1.37-3.74) and RV systolic dysfunction (RR 1.85, 95% CI 1.22-2.81) were associated with increased 28-day mortality rate in addition and independent to LAC + (RR 1.81, 95% CI 1.15-2.84). In conclusion, LV and RV ventricular dysfunction were independently associated with an increased mortality rate, altogether with the presence of cryptic shock.

Fluid Therapy in Dogs and Cats With Sepsis

Sepsis is currently defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Sepsis may occur secondary to infection anywhere in the body, and its pathogenesis is complex and not yet fully understood. Variations in the host immune response result in diverse clinical manifestations, which complicates clinical recognition and fluid therapy both in humans and veterinary species. Septic shock is a subset of sepsis in which particularly profound circulatory, cellular, and metabolic abnormalities are associated with a greater risk of mortality than with sepsis alone. Although septic shock is a form of distributive shock, septic patients frequently present with hypovolemic and cardiogenic shock as well, further complicating fluid therapy decisions. The goals of this review are to discuss the clinical recognition of sepsis in dogs and cats, the basic mechanisms of its pathogenesis as it affects hemodynamic function, and considerations for fluid therapy. Important pathophysiologic changes, such as cellular interaction, microvascular alterations, damage to the endothelial glycocalyx, hypoalbuminemia, and immune paralysis will be also reviewed. The advantages and disadvantages of treatment with crystalloids, natural and synthetic colloids, and blood products will be discussed. Current recommendations for evaluating fluid responsiveness and the timing of vasopressor therapy will also be considered. Where available, the veterinary literature will be used to guide recommendations.

Prognostic Role of Left Ventricular Systolic Function Measured by Speckle Tracking Echocardiography in Septic Shock

Background

Left ventricular (LV) systolic dysfunction is common in septic shock. Global longitudinal strain (GLS) measured by speckle tracking echocardiography (STE) is a useful marker of intrinsic left ventricular systolic function. However, the association between left ventricular GLS and outcome in septic patients is not well understood. We performed this prospective study to investigate the prognostic value of LV systolic function utilizing speckle tracking echocardiography in patients with septic shock.

Methods

All the patients with septic shock based on sepsis-3 definition admitted to the intensive care unit were prospectively studied with STE within 24 hours after the onset of septic shock. Baseline clinical and echocardiographic variables were collected. The primary outcome was in-hospital mortality.

Results

During a 19-month period, 90 consecutive patients were enrolled in the study. The in-hospital mortality rate was 43.3%. Compared with survivors, nonsurvivors exhibited significantly less negative GLS (−13.1 ± 3.3% versus −15.8 ± 2.9%; p < 0.001), which reflected worse LV systolic function. The area under the ROC curves of GLS for the prediction of mortality was 0.76 (95% CI 0.67 to 0.87). Patients with GLS > −14.1% showed a significantly higher mortality rate (67.7% versus 15.6%; p < 0.0001; log‐rank = 23.3; p < 0.0001). In the multivariate analysis, GLS (HR, 1.27; 95% CI 1.07 to 1.50, p = 0.005) and SOFA scores (HR, 1.27; 95% CI 1.08 to 1.50, p = 0.004) were independent predictors of in-hospital mortality.

Conclusions

Our study indicated that LV systolic function measured by STE might be associated with mortality in patients with septic shock.

Subclinical Left Ventricular Systolic Dysfunction in Patients with Septic Shock Based on Sepsis-3 Definition: A Speckle-Tracking Echocardiography Study

Introduction

Left ventricular dysfunction is quite common in septic shock. Speckle-tracking echocardiography (STE) is a novel, highly sensitive method for assessing left ventricular function, capable of detecting subclinical myocardial dysfunction, which is not identified with conventional echocardiography. We sought to evaluate subclinical left ventricular systolic function in patients with septic shock using speckle-tracking echocardiography.

Methods

From May 2017 to December 2018, patients aged ≥18 years admitted to the intensive care unit with the diagnosis of sepsis and septic shock based on the sepsis-3 definition were included. Patients with other causes of cardiac dysfunction were excluded. Transthoracic echocardiography was performed for all the patients within 24 hours of diagnosis. Left ventricular systolic function was assessed using conventional echocardiography and speckle-tracking echocardiography.

Results

Patients with septic shock (n = 90) (study group) and 37 matched patients with sepsis but no septic shock (control group) were included. Left ventricular ejection fraction (LVEF) by conventional echocardiography showed no significant difference between two groups (58.2 ± 9.9 vs. 58.6 ± 8.3, p=0.804). The global longitudinal strain (GLS) by STE was significantly reduced in patients with septic shock compared with that in the control (−14.6 ± 3.3 vs. −17.1 ± 3.3, p < 0.001). Based on the cutoff value of GLS ≥ −15% for the definition of subclinical left ventricular systolic dysfunction, this dysfunction was detected in 50 patients with septic shock (55.6%) and in 6 patients in the control group (16.2%) (p < 0.05).

Conclusions

Speckle-tracking echocardiography can detect early subclinical left ventricular systolic dysfunction via the left ventricular global longitudinal strain compared with conventional echocardiographic parameters in patients with septic shock.

Myocardial Strain and Cardiac Output are Preferable Measurements for Cardiac Dysfunction and Can Predict Mortality in Septic Mice

Background

Sepsis is the overwhelming host response to infection leading to shock and multiple organ dysfunction. Cardiovascular complications greatly increase sepsis‐associated mortality. Although murine models are routinely used for preclinical studies, the benefit of using genetically engineered mice in sepsis is countered by discrepancies between human and mouse sepsis pathophysiology. Therefore, recent guidelines have called for standardization of preclinical methods to document organ dysfunction. We investigated the course of cardiac dysfunction and myocardial load in different mouse models of sepsis to identify the optimal measurements for early systolic and diastolic dysfunction.

Methods and Results

We performed speckle‐tracking echocardiography and assessed blood pressure, plasma inflammatory cytokines, lactate, B‐type natriuretic peptide, and survival in mouse models of endotoxemia or polymicrobial infection (cecal ligation and puncture, [CLP]) of moderate and high severity. We observed that myocardial strain and cardiac output were consistently impaired early in both sepsis models. Suppression of cardiac output was associated with systolic dysfunction in endotoxemia or combined systolic dysfunction and reduced preload in the CLP model. We found that cardiac output at 2 hours post‐CLP is a negative prognostic indicator with high sensitivity and specificity that predicts mortality at 48 hours. Using a known antibiotic (ertapenem) treatment, we confirmed that this approach can document recovery.

Conclusions

We propose a non‐invasive approach for assessment of cardiac function in sepsis and myocardial strain and strain rate as preferable measures for monitoring cardiovascular function in sepsis mouse models. We further show that the magnitude of cardiac output suppression 2 hours post‐CLP can be used to predict mortality.

Sirt3 is a novel target to treat sepsis induced myocardial dysfunction by acetylated modulation of critical enzymes within cardiac tricarboxylic acid cycle

Sepsis induced myocardial dysfunction (SIMD) results in high morbidity and mortality. However, the effective therapeutic strategies for SIMD treatment remain limited. Sirt3 is the main mitochondrial Sirtuin member and is a key modulator of mitochondrial metabolism and function. In this study, we aimed to investigate the effect and mechanism of Sirt3 on SIMD. SIMD was induced by 20 mg/kg Lipopolysaccharides (LPS) injection for 6 h in mice. Sepsis could induce the reduction of cardiac Sirt3 expression and global deficiency of Sirt3 exacerbated cardiac function. Quantitative acetyl-proteomics and cardiac metabolomics analysis revealed that loss of Sirt3 led to hyper-acetylation of critical enzymes within cardiac tricarboxylic acid (TCA) cycle and generation of lactate and NADH, subsequently promotion of cardiac dysfunction after sepsis. Additionally, to evaluate whether Emodin could be utilized as a potential Sirt3 modulator to treat SIMD, male wild type mice (WT mice) or global Sirt3 deficient mice (Sirt3^-/- mice) were intraperitoneally injected with 40 mg/kg Emodin for 5 days followed by 20 mg/kg LPS administration for another 6 h and observed that exogenous administration of Emodin could attenuate myocardial dysfunction in septic WT mice. However, septic Sirt3^-/- mice can not gain benefit on cardiac performance from Emodin infusion. In conclusion, this study presented the protective role of Sirt3 targeting SIMD, which may provide a potential novel approach to maintain normal cardiac performance after sepsis.

Continuous cardiac output assessment or serial echocardiography during septic shock resuscitation?

Septic shock is the leading cause of cardiovascular failure in the intensive care unit (ICU). Cardiac output is a primary component of global oxygen delivery to organs and a sensitive parameter of cardiovascular failure. Any mismatch between oxygen delivery and rapidly varying metabolic demand may result in tissue dysoxia, hence organ dysfunction. Since the intricate alterations of both vascular and cardiac function may rapidly and widely change over time, cardiac output should be measured repeatedly to characterize the type of shock, select the appropriate therapeutic intervention, and evaluate patient's response to therapy. Among the numerous techniques commercially available for measuring cardiac output, transpulmonary thermodilution (TPT) provides a continuous monitoring with external calibration capability, whereas critical care echocardiography (CCE) offers serial hemodynamic assessments. CCE allows early identification of potential sources of inaccuracy of TPT, including right ventricular failure, severe tricuspid or left-sided regurgitations, intracardiac shunt, very low flow states, or dynamic left ventricular outflow tract obstruction. In addition, CCE has the unique advantage of depicting the distinct components generating left ventricular stroke volume (large cavity size vs. preserved contractility), providing information on left ventricular diastolic properties and filling pressures, and assessing pulmonary artery pressure. Since inotropes may have deleterious effects if misused, their initiation should be based on the documentation of a cardiac dysfunction at the origin of the low flow state by CCE. Experts widely advocate using CCE as a first-line modality to initially evaluate the hemodynamic profile associated with shock, as opposed to more invasive techniques. Repeated assessments of both the efficacy (amplitude of the positive response) and tolerance (absence of side-effect) of therapeutic interventions are required to best guide patient management. Overall, TPT allowing continuous tracking of cardiac output variations and CCE appear complementary rather than mutually exclusive in patients with septic shock who require advanced hemodynamic monitoring.

Inodilators in septic shock: should these be used?

Septic shock involves a complex interaction between abnormal vasodilation, relative and/or absolute hypovolemia, myocardial dysfunction, and altered blood flow distribution to the tissues. Fluid administration, vasopressor support and inotropes, represent fundamental pieces of quantitative resuscitation protocols directed to assist the restoration of impaired tissue perfusion during septic shock. Indeed, current recommendations on sepsis management include the use of inotropes in the case of myocardial dysfunction, as suggested by a low cardiac output, increased filling pressures, or persisting signals of tissue hypoperfusion despite an adequate correction of intravascular volume and mean arterial pressure by fluid administration and vasopressor support. Evidence supporting the use of inotropes in sepsis and septic shock is mainly based on physiological studies. Most of them suggest a beneficial effect of inotropes on macro hemodynamics especially when sepsis coexists with myocardial dysfunction; others, however, have demonstrated variable results on regional splanchnic circulation, while others suggest favorable effects on microvascular distribution independently of its impact on cardiac output. Conversely, impact of inodilators on clinical outcomes in this context has been more controversial. Use of dobutamine has not been consistently related with more favorable clinical results, while systematic administration of levosimendan in sepsis do not prevent the development of multiorgan dysfunction, even in patients with evidence of myocardial dysfunction. Nevertheless, a recent metanalysis of clinical studies suggests that cardiovascular support regimens based on inodilators in sepsis and septic shock could provide some beneficial effect on mortality, while other one corroborated such effect on mortality specially in patients with proved lower cardiac output. Thus, using or not inotropes during sepsis and septic shock remains as controversy matter that deserves more research efforts.

Therapeutic effects of dexpanthenol on the cardiovascular and respiratory systems following cecal ligation and puncture-induced sepsis in rats

Cecal ligation and puncture (CLP) is a commonly used model of sepsis in vivo. We investigated the effects of dexpanthenol (DXP) on heart, lung and aorta in CLP-induced sepsis in rats. Rats were divided into four groups of eight: group 1, sham (SH); group 2 (DXP), 500 mg/kg DXP injected intraperitoneally (i.p.); group 3 (CLP), CLP performed; group 4 (CLP + DXP), 500 mg/kg DXP injected i.p. after CLP. Heart, lung and aorta specimens were harvested for histopathological and biochemical analysis. Heart rate increased in group 3 compared to group 1; DXP administration to group 4 did not alleviate this change. In heart tissue samples, MDA levels were decreased significantly in groups 2 and 4 compared to group 3. The levels of GSH in groups 2 and 3 were elevated compared to groups 1 and 2. SOD activity was increased significantly in group 4 compared to group 3. CAT activity for group 4 was increased significantly compared to groups 1 and 3. We found that caspase-9 and caspase-3 activity was increased after application of CLP. Also, DXP treatment decreased the number of caspase-positive cells significantly compared to group 3. DXP appears to be promising for reducing sepsis-related mortality.

Myocardial Depression in Sepsis: Beneficial Adaptation or Sequelae that Requires Treatment?

Myocardial depression is a common yet reversible phenomenon that occurs in patients in septic shock. Initially, it was unclear whether this provided an adaptive survival benefit, as early studies showed decreased mortality in septic patients with myocardial depression. However, subsequent larger studies have debunked this myth. Given that no benefit exists, cardiac dysfunction in septic patients may be monitored via echocardiography and may be treated with inotropic agents. Beta-blockers provide a novel avenue of treatment as they aid in reducing adrenergic overstimulation and cytokine production, which may drive the pathogenesis of septic shock. This review chronicles how the understanding of myocardial depression in sepsis has evolved and how it should be clinically managed.

Prognostic importance of tissue Doppler imaging of systolic and diastolic functions in dogs with severe sepsis and septic shock

The goal of this study was to determine the distribution of left ventricular (LV) systolic and diastolic dysfunctions and their prognostic value in canine parvovirus-infected dogs suffering from severe sepsis and septic shock (SS/SS). Twenty dogs with SS/SS (experimental group) and 18 healthy dogs (control group) were used in the study. Systolic and diastolic dysfunction was present in three (15%) and 14 (70%) diseased dogs, respectively, with both types of dysfunction present in two (10%) of the patients. These dogs were split into two groups: survivors (Sv, n = 14) and non-survivors (non-Sv, n = 6). The pulsed wave tissue Doppler (PW-TDI) septal mitral annulus systolic velocity (LVS'), an index of systolic dysfunction, had a high sensitivity and specificity to differentiate Sv and non-Sv animals, with values of 83.3% (95% CI: 41.6-98.4) and 83.3% (95% CI: 59.8-94.8), respectively, at an optimum cut-off point of ≥ 9.90. The PW-TDI septal early mitral annulus early-diastolic peak velocity (E'), an index of diastolic dysfunction, had the best sensitivity and specificity to differentiate Sv and non-Sv dogs, with values of 100% (95% CI: 55.2-100) and 100% (95% CI: 78.9-100), respectively, at an optimum cut-off point of ≤ 6.50. Therefore, diastolic dysfunction determined by E' is a good independent outcome predictor.

Alprostadil attenuates LPS-induced cardiomyocyte injury by inhibiting the Wnt5a/JNK/NF-κB pathway

Background

Clinical research has demonstrated that alprostadil has an anti-inflammatory effect; however, to date, its molecular mechanisms remain unclear. This study aimed to examine the anti-inflammatory activity and related mechanisms of alprostadil in lipopolysaccharide (LPS)-treated H9c2 cells.

Methods

Cell morphology was observed under an inverted light microscope, while cell viability was assessed with the 3‑(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay. Enzyme-linked immunosorbent assays (ELISA) were conducted to study biochemical indicators of cellular damage, such as released lactate dehydrase (LDH) and troponin, and inflammatory cytokine levels including interleukin-1β (IL-1β), IL-6, IL-17, and tumor necrosis factor-α (TNF-α). The mRNA expression levels of Wnt5a, c‑jun N‑terminal kinase (JNK), and nuclear factor kappa B (NF-κB) were further investigated by real-time quantitative polymerase chain reaction (RT-PCR). The effects of alprostadil on the Wnt5a/JNK/NF-κB pathway in H9c2 cells was examined by Western blotting.

Results

Alprostadil increased the cell viability of LPS-stimulated H9c2 cells, reduced LDH and troponin production, and attenuated IL-1β, IL-6, IL-17, and TNF-α secretion. Moreover, alprostadil reduced the mRNA expression of Wnt5a, JNK, and NF-κB and decreased the expression of Wnt5a, NF-κB, and the ratio of p‑JNK/JNK in H9c2 cells treated with LPS. The siWnt5a or JNK inhibitor SP600125 significantly augmented the inhibitory effects of alprostadil on the Wnt5a/JNK/NF-κB pathway.

Conclusion

Our results show that alprostadil has anti-inflammatory effects and could attenuate LPS-induced injury in H9c2 cardiomyocytes via the Wnt5a/JNK/NF-κB pathway.

Sepsis-induced myocardial dysfunction

PURPOSE OF REVIEW

Sepsis leads to a complex intramyocardial inflammatory response that results in sepsis-induced myocardial dysfunction. Here, recent findings are reviewed in a physiologic context.

RECENT FINDINGS

Decreased systolic contractility during sepsis limits ventricular ejection and stroke volume. Initially, this effect is compensated for by increased diastolic filling during volume resuscitation. Reduced afterload due to arterial vasodilation also compensates so that cardiac output can be maintained or increased. Recent results recognize the importance of diastolic dysfunction, reduced ventricular diastolic compliance that impedes ventricular filling. Diastolic dysfunction becomes increasingly important as severity of septic shock increases. When impaired ventricular ejection is coupled with limited diastolic filling, stroke volume must decrease. Accordingly, diastolic dysfunction is more closely related to mortality than systolic dysfunction. Recent trials of beta-adrenergic agonists and levosimendan have been disappointing, while approaches to modulating the intramyocardial inflammatory response show promise.

SUMMARY

Sepsis-induced myocardial dysfunction is increasingly recognized as a major contributor to outcome of septic shock. Significant strides have been made in understanding the intramyocardial inflammatory response that causes myocardial dysfunction. A number of novel approaches show promise by modulating the intramyocardial inflammatory response.

Sepsis: The evolution in definition, pathophysiology, and management

There has been a significant evolution in the definition and management of sepsis over the last three decades. This is driven in part due to the advances made in our understanding of its pathophysiology. There is evidence to show that the manifestations of sepsis can no longer be attributed only to the infectious agent and the immune response it engenders, but also to significant alterations in coagulation, immunosuppression, and organ dysfunction. A revolutionary change in the way we manage sepsis has been the adoption of early goal-directed therapy. This involves the early identification of at-risk patients and prompt treatment with antibiotics, hemodynamic optimization, and appropriate supportive care. This has contributed significantly to the overall improved outcomes with sepsis. Investigation into clinically relevant biomarkers of sepsis are ongoing and have yet to yield effective results. Scoring systems such as the sequential organ failure assessment and Acute Physiology and Chronic Health Evaluation help risk-stratify patients with sepsis. Advances in precision medicine techniques and the development of targeted therapy directed at limiting the excesses of the inflammatory and coagulatory cascades offer potentially viable avenues for future research. This review summarizes the progress made in the diagnosis and management of sepsis over the past two decades and examines promising avenues for future research.

New-Onset Heart Failure and Mortality in Hospital Survivors of Sepsis-Related Left Ventricular Dysfunction

BACKGROUND

The association between new-onset left ventricular (LV) dysfunction during sepsis with long-term heart failure outcomes is lesser understood.

METHODS

Retrospective cohort study of all adult patients with severe sepsis and septic shock between 2007 and 2014 who underwent echocardiography within 72 h of admission to the intensive care unit. Patients with prior heart failure, LV dysfunction, and structural heart disease were excluded. LV systolic dysfunction was defined as LV ejection fraction <50% and LV diastolic dysfunction as ≥grade II. Primary composite outcome included new hospitalization for acute decompensated heart failure and all-cause mortality at 2-year follow-up. Secondary outcomes included persistent LV dysfunction, and hospital mortality and length of stay.

RESULTS

During this 8-year period, 434 patients with 206 (48%) patients having LV dysfunction were included. The two groups had similar baseline characteristics, but those with LV dysfunction had worse function as demonstrated by worse LV ejection fraction, cardiac index, and LV diastolic dysfunction. In the 331 hospital survivors, new-onset acute decompensated heart failure hospitalization did not differ between the two cohorts (15% vs. 11%). The primary composite outcome was comparable at 2-year follow-up between the groups with and without LV dysfunction (P = 0.24). Persistent LV dysfunction was noted in 28% hospital survivors on follow-up echocardiography. Other secondary outcomes were similar between the two groups.

CONCLUSIONS

In patients with severe sepsis and septic shock, the presence of new-onset LV dysfunction did not increase the risk of long-term adverse heart failure outcomes.

Variability of mitochondrial respiration in relation to sepsis-induced multiple organ dysfunction

Ample experimental evidence suggests that sepsis could interfere with any mitochondrial function; however, the true role of mitochondrial dysfunction in the pathogenesis of sepsis-induced multiple organ dysfunction is still a matter of controversy. This review is primarily focused on mitochondrial oxygen consumption in various animal models of sepsis in relation to human disease and potential sources of variability in experimental results documenting decrease, increase or no change in mitochondrial respiration in various organs and species. To date, at least three possible explanations of sepsis-associated dysfunction of the mitochondrial respiratory system and consequently impaired energy production have been suggested: 1. Mitochondrial dysfunction is secondary to tissue hypoxia. 2. Mitochondria are challenged by various toxins or mediators of inflammation that impair oxygen utilization (cytopathic hypoxia). 3. Compromised mitochondrial respiration could be an active measure of survival strategy resembling stunning or hibernation. To reveal the true role of mitochondria in sepsis, sources of variability of experimental results based on animal species, models of sepsis, organs studied, or analytical approaches should be identified and minimized by the use of appropriate experimental models resembling human sepsis, wider use of larger animal species in preclinical studies, more detailed mapping of interspecies differences and organ-specific features of oxygen utilization in addition to use of complex and standardized protocols evaluating mitochondrial respiration.

Osteopontin Expression in Cardiomyocytes Is Increased in Pediatric Patients With Sepsis or Pneumonia

Sepsis and pneumonia are major causes of death in the United States, and their pathophysiology includes infection with inflammation and immune dysfunction. Both sepsis and pneumonia cause cardiovascular dysfunction. The expression of Osteopontin (OPN) in cardiomyocytes of patients with sepsis or pneumonia, and its role the induced cardiac dysfunction have not been thoroughly investigated. OPN is a matricellular protein synthesized by multiple diseased tissues and cells including cardiomyocytes. Here, we studied the expression of OPN protein using immunofluorescence in human myocardial autopsy tissues from pediatric and mid age or elderly patients with sepsis and/or pneumonia. Fourteen human myocardial tissues from six pediatric patients and eight mid-age or elderly patients were studied. Immunofluorescence was used to investigate the expression of OPN in paraffin-embedded heart sections co-stained with the myocyte markers Actin Alpha 1 (ACTA1) and Myosin Light Chain 2 (MLC2). A quantitative analysis was performed to determine the number of ACTA1 and MLC2 positive cardiomyocytes that express OPN. The results showed that OPN expression was significantly increased in cardiomyocytes in the hearts from pediatric patients with sepsis and/or pneumonia (N = 3) relative to pediatric patients without sepsis/pneumonia (N = 3), or adult to elderly patients with sepsis/pneumonia (N = 5). Among the older septic hearts, higher levels of cardiomyocyte OPN expression was seen only in conjunction with severe coronary arterial occlusion. This is the first study to document increased OPN expression in cardiomyocytes of pediatric subjects with sepsis or pneumonia. Our findings highlight a potentially important role for OPN in sepsis- or pneumonia-mediated cardiac dysfunction in pediatric patients.