Elevated cardiac troponin I in sepsis and septic shock: no evidence for thrombus associated myocardial necrosis

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.

Spleen tyrosine kinase: a novel pharmacological target for sepsis-induced cardiac dysfunction and multi-organ failure

Sepsis is a systemic condition caused by a dysregulated host response to infection and often associated with excessive release of proinflammatory cytokines resulting in multi-organ failure (MOF), including cardiac dysfunction. Despite a number of effective supportive treatments (e.g. ventilation, dialysis), there are no specific interventions that prevent or reduce MOF in patients with sepsis. To identify possible intervention targets, we re-analyzed the publicly accessible Gene Expression Omnibus accession GSE131761 dataset, which revealed an increased expression of spleen tyrosine kinase (SYK) in the whole blood of septic patients compared to healthy volunteers. This result suggests a potential involvement of SYK in the pathophysiology of sepsis. Thus, we investigated the effects of the highly selective SYK inhibitor PRT062607 (15mg/kg; i.p.) on sepsis-induced cardiac dysfunction and MOF in a clinically-relevant, murine model of sepsis. PRT062607 or vehicle (saline) was administered to 10-weeks-old C57BL/6 mice at 1h after the onset of sepsis induced by cecal ligation and puncture (CLP). Antibiotics (imipenem/cilastatin; 2mg/kg; s.c.) and analgesic (buprenorphine; 0.05mg/kg; i.p.) were administered at 6h and 18h post-CLP. After 24h, cardiac function was assessed in vivo by echocardiography and, after termination of the experiments, serum and cardiac samples were collected to evaluate the effects of SYK inhibition on the systemic release of inflammatory mediators and the degree of organ injury and dysfunction. Our results show that treatment of CLP-mice with PRT062607 significantly reduces systolic and diastolic cardiac dysfunction, renal dysfunction and liver injury compared to CLP-mice treated with vehicle. In addition, the sepsis-induced systemic inflammation (measured as an increase in inflammatory cytokines and chemokines in the serum) and the cardiac activation of NF-kB (IKK) and the NLRP3 inflammasome were significantly reduced in CLP-mice treated with PRT062607. These results demonstrate, for the first time, that SYK inhibition 1h after the onset of sepsis reduces the systemic inflammation, cardiac dysfunction and MOF, suggesting a potential role of the activation of SYK in the pathophysiology of sepsis. Novel therapeutic strategies that inhibit SYK activity may be of benefit in patients with diseases associated with local or systemic inflammation including sepsis.

Combination of Anti-CD40 and Anti-CD40L Antibodies as Co-Stimulation Blockade in Preclinical Cardiac Xenotransplantation

The blockade of the CD40/CD40L immune checkpoint is considered essential for cardiac xenotransplantation. However, it is still unclear which single antibody directed against CD40 or CD40L (CD154), or which combination of antibodies, is better at preventing organ rejection. For example, the high doses of antibody administered in previous experiments might not be feasible for the treatment of humans, while thrombotic side effects were described for first-generation anti-CD40L antibodies. To address these issues, we conducted six orthotopic pig-to-baboon cardiac xenotransplantation experiments, combining a chimeric anti-CD40 antibody with an investigational long-acting PASylated anti-CD40L Fab fragment. The combination therapy effectively resulted in animal survival with a rate comparable to a previous study that utilized anti-CD40 monotherapy. Importantly, no incidence of thromboembolic events associated with the administration of the anti-CD40L PAS-Fab was observed. Two experiments failed early because of technical reasons, two were terminated deliberately after 90 days with the baboons in excellent condition and two were extended to 120 and 170 days, respectively. Unexpectedly, and despite the absence of any clinical signs, histopathology revealed fungal infections in all four recipients. This study provides, for the first time, insights into a combination therapy with anti-CD40/anti-CD40L antibodies to block this immune checkpoint.

Cord blood troponin I levels: biomarker evidence of fetal cardiac injury in intrahepatic cholestasis of pregnancy

BACKGROUND

Intrahepatic cholestasis of pregnancy has been linked to sudden stillbirth. The suddenness of the stillbirths in these cases have led clinicians to suspect that the pathogenesis of stillbirth in women with intrahepatic cholestasis of pregnancy is not related to asphyxia but rather to an undefined etiology. One leading hypothesis relates certain bile acid metabolites to myocardial injury.

OBJECTIVE

The purpose of this study was to determine whether cord blood troponin I levels are increased in fetuses born to mothers with a diagnosis of intrahepatic cholestasis of pregnancy.

STUDY DESIGN

A prospective, case-control study was performed at a single institution between 2017 to 2019 in which 87 pregnant patients with a diagnosis of intrahepatic cholestasis of pregnancy (total bile acids ≥10 μmol/L) were enrolled as cases and 122 randomly selected pregnant patients (asymptomatic with intrapartum total bile acids <10 μmol/L) were enrolled as controls. Cord blood troponin I levels were measured at delivery in both groups using a commercially available chemiluminescent immunoassay. Values ≤0.04 ng/mL were considered negative. Values >0.04 ng/mL were considered positive. The primary outcome was the presence of elevated troponin levels in both cases and controls as a surrogate marker for cardiac status. Our secondary outcomes included neonatal intensive care unit stay, low Apgar scores, neonatal acidosis, and hypoxia indicated by cord blood pH and base excess levels at the time of birth. Chi square and t tests were performed to compare social and obstetrical variables. A P value of <.05 was considered significant. A stratification by total bile acids range of <40 μmol/L, 40 to 100 μmol/L, and >100 μmol/L was performed to assess the relationship between the different severities of intrahepatic cholestasis of pregnancy (by risk of fetal demise with those with total bile acids of >100 μmol/L considered at greatest risk) and the likelihood of a positive troponin I result. Finally, a logistic regression analysis was performed to determine if levels of ≥10 μmol/L were associated with elevated troponin levels.

RESULTS

The mean gestational age at delivery was 38.96±1.47 and 37.71±1.59 weeks of gestation in the controls and cases respectively (P<.001). The mean total bile acids values were 5.2±1.28 ng/mL and 43.2±40.62 ng/mL in the controls and cases respectively (P<.001). Cord blood troponin I was positive in 15 of 122 (12.30%) controls and in 20 of 87 (22.99%) cases. (P<.001). When further stratified by total bile acids levels of <40, 40 to 100, and >100 μmol/L, we found a positive correlation between higher total bile acids levels and a positive troponin I test (P=.002). When controlling for gestational age at delivery, maternal age, and body mass index, higher total bile acids levels were associated with a positive troponin I level (adjusted odds ratio, 1.015; 95% confidence interval, 1.004-1.026).

CONCLUSION

Elevated troponin I was more likely to be found in patients with intrahepatic cholestasis of pregnancy than in those without intrahepatic cholestasis of pregnancy. When stratified by total bile acids levels, a positive troponin I level was more likely to be found with higher levels of total bile acids. In addition, as total bile acids levels increased, they were more likely to be associated with a positive troponin I level. Although there were no stillbirths in our cohort, our findings suggest a potential relationship between cardiac injury and high levels of total bile acids demonstrated by the presence of elevated troponin I levels in cord blood at the time of birth.

Role of toll-like receptor-mediated pyroptosis in sepsis-induced cardiomyopathy

Sepsis, a life-threatening dysregulated status of the host response to infection, can cause multiorgan dysfunction and mortality. Sepsis places a heavy burden on the cardiovascular system due to the pathological imbalance of hyperinflammation and immune suppression. Myocardial injury and cardiac dysfunction caused by the aberrant host responses to pathogens can lead to cardiomyopathy, one of the most critical complications of sepsis. However, many questions about the specific mechanisms and characteristics of this complication remain to be answered. The causes of sepsis-induced cardiac dysfunction include abnormal cardiac perfusion, myocardial inhibitory substances, autonomic dysfunction, mitochondrial dysfunction, and calcium homeostasis dysregulation. The fight between the host and pathogens acts as the trigger for sepsis-induced cardiomyopathy. Pyroptosis, a form of programmed cell death, plays a critical role in the progress of sepsis. Toll-like receptors (TLRs) act as pattern recognition receptors and participate in innate immune pathways that recognize damage-associated molecular patterns as well as pathogen-associated molecular patterns to mediate pyroptosis. Notably, pyroptosis is tightly associated with cardiac dysfunction in sepsis and septic shock. In line with these observations, induction of TLR-mediated pyroptosis may be a promising therapeutic approach to treat sepsis-induced cardiomyopathy. This review focuses on the potential roles of TLR-mediated pyroptosis in sepsis-induced cardiomyopathy, to shed light on this promising therapeutic approach, thus helping to prevent and control septic shock caused by cardiovascular disorders and improve the prognosis of sepsis patients.

First Sampled High-Sensitive Cardiac Troponin T is Associated With One-Year Mortality in Sepsis Patients and 30- to 365-Day Mortality in Sepsis Survivors

BACKGROUND

Previous studies using cardiac troponin levels to investigate the relationship between myocardial injury and mortality in sepsis patients have been conflicting. Our aim was to investigate the relationship between plasma high-sensitive cardiac troponin T (hs-cTnT) level and 30-day and 1-year mortality in sepsis patients and 30- to 365-day mortality in sepsis survivors.

METHODS

Sepsis patients requiring vasopressor support and admitted to our institution between 2012 and 2021 (n = 586) were included in this retrospective cohort study. Elevated hs-cTnT values (≥15 ng/L) were divided into quartiles (Q): Q1 15-35 ng/L; Q2 36-61 ng/L; Q3 62-125 ng/L; Q4 126-8630 ng/L. Stratified Kaplan-Meier curves and multivariable Cox regression were used for survival analyses.

RESULTS

First sampled hs-cTnT was elevated in 529 (90%) patients. One-year mortality was 45% (n = 264). Increasing level of hs-cTnT was independently associated with higher adjusted hazard ratios (HR) for 1-year mortality compared with normal levels: Q1 HR 2.9 (95% confidence interval [CI], 1.03-8.1); Q2 HR 3.5 (95% CI, 1.2-9.8); Q3 HR 4.8 (95% CI, 1.7-13.4); Q4 HR 5.7 (95% CI, 2.1-16). In acute phase survivors, first sampled hs-cTnT was an independent predictor of 30- to 365-day mortality (HR 1.3; 95% CI, 1.1-1.6 per loge hs-cTnT).

CONCLUSIONS

First sampled plasma hs-cTnT in critically ill sepsis patients was independently associated with 30-day and 1-year mortality. Importantly, first sampled hs-cTnT was associated with mortality during the convalescence phase (30- to 365-day) and could be a feasible marker to identify acute phase survivors at high risk of death.

Variation in Troponin I Measurement and the Cardiovascular Management Approach Following Elevated Troponin I Among Critically Ill Patients With Sepsis

Troponin I is frequently elevated in sepsis, but optimal clinical approaches to diagnosis and management of troponin I during sepsis are unclear.

OBJECTIVES

We aimed to describe the variation in troponin I measurement and the cardiovascular diagnostic and therapeutic approach to elevated troponin I among critically ill adults with sepsis.

DESIGN SETTING AND PARTICIPANTS

Observational cohort study of the hospital-level variation in serial troponin I measurement, trending troponin I to peak, echocardiography, cardiac stress test, cardiac catheterization, antiplatelet agents, therapeutic anticoagulation, beta-blockers, and statins quantified using hospital median odds ratios-the median odds of receiving an intervention at randomly selected higher versus lower rate hospitals-derived from multivariable-adjusted random-effects logistic regression models with hospital site as the random effect. The Premier Healthcare Database was used. Patients were adults aged greater than 18 years admitted to the ICU with sepsis from 2016 to 2020.

MAIN OUTCOMES AND MEASURES

The hospital-level median odds ratios of troponin I measurement as well as cardiovascular diagnostics and therapeutics.

RESULTS

Among 85,830 adults with sepsis, 53,058 (61.8%) had a troponin I measured, with a median odds ratio of troponin measurement across hospitals of 5.30 (95% CI, 4.98-5.67). Among 27,665 adults (32.2%) with sepsis and an elevated troponin I level, 84.8% had serial troponin I measurements, 66.0% had troponin trended to peak level, 66.7% had an echocardiogram, 4.1% had a cardiac stress test, 6.6% underwent cardiac catheterization, 48.3% received antiplatelet agents, 8.3% received therapeutic anticoagulation, 50.5% received beta-blockers, and 38.1% received statins. The median odds ratios between hospitals for cardiovascular diagnostics and therapeutics ranged from 1.28 (95% CI, 1.24-1.32) for use of beta-blockers to 7.58 (95% CI, 6.43-8.77) for use of therapeutic anticoagulation.

CONCLUSIONS AND RELEVANCE

Both troponin I measurement and the approach to an elevated troponin I among critically ill adults with sepsis varied widely across hospitals consistent with disparate practice and care efficiency. Prospective studies are needed to guide an informed approach to troponin I measurement and cardiovascular evaluation in sepsis.

Cardiac Troponin I Reveals Diagnostic and Prognostic Superiority to Aminoterminal Pro-B-Type Natriuretic Peptide in Sepsis and Septic Shock

Data regarding the prognostic value of cardiac biomarkers in patients suffering from sepsis or septic shock is scarce. Studies investigating the prognostic role of cardiac biomarkers in patients with sepsis and septic shock were commonly published prior to the sepsis-3 criteria and were often not restricted to septic patients only, too. This study investigated the diagnostic and prognostic value of the aminoterminal pro-B-type Natriuretic Peptide (NT-pro BNP) and cardiac troponin I (cTNI) in patients with sepsis and septic shock. Consecutive patients with sepsis and septic shock were included from 2019 to 2021. Blood samples were retrieved from the day of disease onset (i.e., day 1), day 2 and 3. Firstly, the diagnostic value of the NT-pro BNP and cTNI to diagnose sepsis or septic shock was tested. Secondly, the prognostic value of the NT-pro BNP and cTNI was examined with regard to the 30-day all-cause mortality. The statistical analyses included univariable t-tests, Spearman’s correlations, C-statistics, Kaplan–Meier analyses and Cox proportional regression analyses. A total of 162 patients were included prospectively, of which 57% had a sepsis and 43% a septic shock. The overall rate of all-cause mortality at 30 days was 53%. With an area under the curve (AUC) of 0.658 on day 1 and 0.885 on day 3, cTNI expressed a better diagnostic value than NT-pro BNP, especially on day 3 (ΔAUCd3 = 0.404; p = 0.022). Furthermore, cTNI displayed a moderate but slightly better prognostic value than NT-pro BNP on all examined days (AUC for cTNI, d1 = 0.635; 95% CI 0.541–0.729; p = 0.007 vs. AUC for NT-pro BNP, d1 = 0.582; 95% CI 0.477–0.687; p = 0.132). In conclusion, cTNI was a reliable diagnostic parameter for the diagnosis of sepsis and septic shock, as well as a reliable prognostic tool with regard to 30-day all-cause mortality in patients suffering from sepsis and septic shock.

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.

Etiology of Myocardial Injury in Critically Ill Patients with Sepsis: A Cohort Study

RATIONALE

Myocardial injury occurs frequently during sepsis and is independently associated with mortality. However, its etiology remains largely unknown.

OBJECTIVE

Our aim was to assess the relative contributions of hyperinflammation, activated coagulation, and endothelial dysfunction to myocardial injury in critically ill patients with sepsis.

METHODS

We included consecutive patients with sepsis presenting to two tertiary intensive care units in the Netherlands between 2011 and 2013. High-sensitivity cardiac troponin I (hscTnI), as well as a wide range of plasma biomarkers related to inflammation, coagulation, and endothelial function were measured. Structural equation modeling (SEM) was used to construct latent variables representing each of these pathophysiological constructs, and to subsequently study their associations with troponin elevation while adjusting for confounders.

RESULTS

We analyzed 908 (88%) of 1037 eligible patients, 553 (61%) of whom had raised hs-cTnI levels upon intensive care unit admission. The latent variables included interleukin (IL)-6, IL-8 and IL-1β for inflammation; platelet count, prothrombin time and protein C for coagulation; and sE-selectin, intercellular adhesion molecule-1 and angiopoietin-2 for endothelial function. After adjustment for age and cardiovascular comorbidities, SEM analysis showed that activated coagulation was independently associated with elevated troponin during sepsis (standardized regression coefficient 0.551, 95% CI 0.257-0.845, p-value <0.001), whereas hyperinflammation and endothelial dysfunction were not (standardized regression coefficients -0.161, 95% CI -0.418-0.096, and -0.054, 95% CI -0.168-0.060, respectively).

CONCLUSIONS

Our findings suggest that myocardial injury during sepsis is mediated by systemic activation of coagulation, rather than by circulating inflammatory mediators or by activation of the endothelium. These findings may guide evaluation of strategies to protect the myocardium during sepsis. Clinical trial registered with clinicaltrials.gov (NCT01905033).

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.

Diagnosis, Investigation and Management of Patients with Acute and Chronic Myocardial Injury

The application of high-sensitivity cardiac troponins in clinical practice has led to an increase in the recognition of elevated concentrations in patients without myocardial ischaemia. The Fourth Universal Definition of Myocardial Infarction encourages clinicians to classify such patients as having an acute or chronic myocardial injury based on the presence or absence of a rise or a fall in cardiac troponin concentrations. Both conditions may be caused by a variety of cardiac and non-cardiac conditions, and evidence suggests that clinical outcomes are worse than patients with myocardial infarction due to atherosclerotic plaque rupture, with as few as one-third of patients alive at 5 years. Major adverse cardiovascular events are comparable between populations, and up to three-fold higher than healthy individuals. Despite this, no evidence-based strategies exist to guide clinicians in the investigation of non-ischaemic myocardial injury. This review explores the aetiology of myocardial injury and proposes a simple framework to guide clinicians in early assessment to identify those who may benefit from further investigation and treatment for those with cardiovascular disease.

Myocardial Injury in Critically Ill Patients with Community-acquired Pneumonia. A Cohort Study

Rationale: Myocardial injury, as reflected by elevated cardiac troponin levels in plasma, is common in patients with community-acquired pneumonia (CAP), but its temporal dynamics and etiology remain unknown. Objectives: Our aim was to determine the incidence of troponin release in patients with CAP and identify risk factors that may point to underlying etiologic mechanisms. Methods: We included consecutive patients admitted with severe CAP to two intensive care units in the Netherlands between 2011 and 2015. High-sensitivity cardiac troponin I was measured daily during the first week. We used multivariable linear regression to identify variables associated with troponin release on admission, and we used mixed-effects regression to model the daily rise and fall of troponin levels over time. Results: Of 200 eligible patients, 179 were included, yielding 792 observation days. A total of 152 (85%) patients developed raised troponin levels greater than 26 ng/L. Baseline factors independently associated with troponin release included coronary artery disease (176% increase; 95% confidence interval [CI], 11-589), smoking (248% increase; 95% CI, 33-809), and higher Acute Physiology and Chronic Health Evaluation IV score (2% increase; 95% CI, 0.8-3.3), whereas Staphylococcus aureus as a causative pathogen was protective (70% reduction; 95% CI, 18-89). Time-dependent risk factors independently associated with daily increase in troponin concentrations included reduced platelet count (2.3% increase; 95% CI, 0.6-4), tachycardia (1.5% increase; 95% CI, 0.1-2.9), hypotension (6.2% increase; 95% CI, 2.1-10.6), dobutamine use (44% increase; 95% CI, 12-85), prothrombin time (8.2% increase; 95% CI, 0.2-16.9), white cell count (1.7% increase; 95% CI, 0-3.5), and fever (22.7% increase; 95% CI, 0.1-49.6). Conclusions: Cardiac injury develops in a majority of patients with severe CAP. Myocardial oxygen supply-demand mismatch and activated inflammation/coagulation are associated with this injury. Clinical trial registered with www.clinicaltrials.gov (NCT01905033).

Toll-Like Receptor-Mediated Cardiac Injury during Experimental Sepsis

Sepsis is associated with global cardiac dysfunction and with high mortality rate. The development of septic cardiomyopathy is due to complex interactions of damage-associated molecular patters, cytokines, and complement activation products. The aim of this study was to define the effects of sepsis on cardiac structure, gap junction, and tight junction (TJ) proteins. Sepsis was induced by cecal ligation and puncture in male C57BL/6 mice. After a period of 24 h, the expression of cardiac structure, gap junction, and TJ proteins was determined. Murine HL-1 cells were stimulated with LPS, and mRNA expression of cardiac structure and gap junction proteins, intracellular reactive oxygen species, and troponin I release was analyzed. Furthermore, pyrogenic receptor subtype 7 (P2X7) expression and troponin I release of human cardiomyocytes (iPS) were determined after LPS exposure. In vivo, protein expression of connexin43 and α-actinin was decreased after the onset of polymicrobial sepsis, whereas in HL-1 cells, mRNA expression of connexin43, α-actinin, and desmin was increased in the presence of LPS. Expression of TJ proteins was not affected in vivo during sepsis. Although the presence of LPS and nigericin resulted in a significant troponin I release from HL-1 cells. Sepsis affected cardiac structure and gap junction proteins in mice, potentially contributing to compromised cardiac function.

Type 2 myocardial infarction: is it a geriatric syndrome?

Type 2 myocardial infarctions (T2-MI) is a type of necrosis that results from reduced oxygen supply and/or increased demand secondary to other causes unrelated to acute coronary atherothrombosis. The development and implementation of sensitive and high-sensitivity cardiac necrosis marker and the age-related increase of comorbidity lead to a boost of the frequency of T2-MI. T2-MI is often a complication of a high degree of clinical frailty in older adults, emerging as a "geriatric syndrome". Age-related non-cardiovascular causes may be the triggering factors and are strongly associated with the diagnosis, treatment, and prognosis of T2-MI. To date, there are no guidelines on management of this pathology in advancing age. Patient-centered approach and comprehensive geriatric assessment play a key role in the diagnosis, therapy and prognosis of geriatric patients with T2-MI.

High-Sensitivity Troponin T Testing: Consequences on Daily Clinical Practice and Effects on Diagnosis of Myocardial Infarction

It remains unclear how introduction of high-sensitivity troponin T testing, as opposed to conventional troponin testing, has affected the diagnosis of acute myocardial infarction (AMI) and resource utilization in unselected hospitalized patients. In this retrospective analysis, we include all consecutive cases from our center during two corresponding time frames (10/2016-04/2017 and 10/2017-04/2018) for which different troponin tests were performed: conventional troponin I (cTnI) and high-sensitivity troponin T (hs-TnT) assays. Testing was performed in 18,025 cases. The incidence of troponin levels above the 99th percentile was significantly higher in cases tested using hs-TnT. This was not associated with increased utilization of echocardiography, coronary angiography, or percutaneous coronary intervention. Although there were no changes in local standard operating procedures, study site personnel, or national coding guidelines, the number of coded AMI significantly decreased after introduction of hs-TnT. In this single-center retrospective study comprising 18,025 mixed medical and surgical cases with troponin testing, the introduction of hs-TnT was not associated with changes in resource utilization among the general cohort, but instead, led to a decrease in the international classification of diseases (ICD)-10 coded diagnosis of AMI.

Emerging protective roles of shengmai injection in septic cardiomyopathy in mice by inducing myocardial mitochondrial autophagy via caspase-3/Beclin-1 axis

BACKGROUND

Sepsis, a life-threatening systemic syndrome related to inflammatory response, usually accompanied by major organ dysfunctions. The aim of the present study was to elucidate the role by which Shengmai injection (SMI) acts to septic cardiomyopathy.

METHODS

Initially, the induced mice with septic cardiomyopathy were treated with SMI or normal saline (NS) with oe-caspase-3, and HL-1 cells were treated with oe-Beclin-1 and oe-caspase-3 and then cultured with lipopolysaccharide (LPS). Subsequently, we measured the cardiac troponin I (cTnI) level, and expression of mitochondrial autophagy protein (parkin and pink1) and myocardial cell autophagy-related proteins (LC3-II and LC3-I). Additionally, we identified the cleavage of Beclin-1 by caspase-3 and detected the changes of mitochondrial membrane potential, level of reactive oxygen species (ROS), and apoptosis of myocardial cells in myocardial tissues of mice.

RESULTS

It has been demonstrated that SMI contributed to the increase of myocardial mitochondrial autophagy, reduction of cTnI level, and elevation of mitochondrial membrane potential in septic cardiomyopathy mice. Both in vitro and in vivo experiments showed that caspase-3 promoted cleavage of Beclin-1 and release of ROS, whereas repressed lipopolysaccharide (LPS)-induced mitochondrial autophagy. Furthermore, the facilitation of myocardial mitochondrial autophagy and protection of myocardial mitochondria by SMI through inhibition of cleavage Beclin-1 by caspase-3 in septic cardiomyopathy mice were also proved by in vivo experiments.

CONCLUSION

Taken together, SMI could protect myocardial mitochondria by promoting myocardial mitochondrial autophagy in septic cardiomyopathy via inhibition of cleavage of Beclin-1 by caspase-3. Our study demonstrates that SMI could represent a novel target for treatment of septic cardiomyopathy.

High-sensitivity troponin assays: development and utility in a modern health-care system

Introduction: The introduction of cardiac troponin (cTn) assays have revolutionized the diagnosis and management of acute myocardial infarction in Emergency Departments worldwide. Its success has led to significant research and development investment in this area culminating in the development of newer high-sensitivity cardiac troponin assays (hs-cTn). While these newer assays allow for more rapid diagnosis by decreasing the time interval between serial data points, there is an inevitable trade off between increasing sensitivity and specificity. This review examines in detail the introduction and implementation of hs-cTN and its implications for clinical practice.Areas covered: This article reviews the history and development of high-sensitivity troponin assays and their application to clinical practice and current evidence base. It also discusses both the positive and negative aspects of the continuing increasing sensitivity of biochemical assays and the translation of this into clinical practice. Potential future developments are also discussed.Expert commentary: It is clear that there are many benefits to detecting extremely low concentration of cardiac troponin including the development of rapid rule out algorithms and the cost and time-saving advantages associated with the quicker movement of patients through the health-care system. It is important to note however that detecting troponin at very low concentrations also dramatically increases the false-positive rates and leads to a potentially large increase in invasive testing and diagnosis of myocardial infarction.

Prognostic Value of High-sensitivity Troponin I in Patients with Septic Shock: A Prospective Observational Study

BACKGROUND

Myocardial dysfunction is one of the mechanisms involved in the pathophysiology of septic shock. The role of troponin as a surrogate of myocardial injury in septic shock is still debated. The aim of this study was to assess the prognostic value of high-sensitivity cardiac troponin I (hs-cTnI) assay in predicting 28-day mortality in patients with septic shock.

MATERIALS AND METHODS

Prospective study including 75 patients with septic shock admitted to a medico-surgical ICU from January to December 2017. Patients under the age of 18 years, known pregnancy and patients in post-cardiac arrest were excluded. Clinical and demographic data including age, gender, comorbidities, SAPS II and SOFA scores were collected. Hs-cTnI was measured soon after admission and 12, 24, 48 and 72 after. Receiver operating characteristic (ROC) analysis was performed to identify the most useful troponin I cut-off level for the prediction of 28-day mortality. A p <0.05 was considered significant.

RESULTS

Seventy-five (M/F = 53/22) patients with septic shock were included in the study. The median SOFA and SAPS II scores were 10 and 42, respectively. The median duration of mechanical ventilation was 8 days and the median length of ICU stay was 11 days. The 28-day mortality was 54.6%. We found a high prevalence (47%) of elevated hs-cTnI in patients with septic shock. Median hs-cTnI on admission in the whole group was 36 ng/L. The 28-day mortality was found to be related to age (p <0.001), SAPS II score (p = 0.001), mean arterial pressure (p = 0.038), lactate (p <0.001) and glomerular filtration rate (p <0.001).Hs-cTnI levels were significantly higher in non-survival group than survival one at all time points: H12 (p = 0.006), H24 (p = 0.003), H48 (p = 0.005) and H72 (p=0.001). In multivariate analysis, hs-cTnI at H72 was independently associated with 28-day mortality.

CONCLUSION

Hs-cTnI elevation at 72 hours was associated with 28-day mortality in septic shock patients.

HOW TO CITE THIS ARTICLE

Jendoubi A, Jerbi S, Maamar E, Abbess A, Samoud Z, Kanzari L, et al. Prognostic Value of High-Sensitivity Troponin I in Patients with Septic Shock: A Prospective Observational Study. Indian J Crit Care Med 2019;23(7):320-325.

Troponin I at admission in the intensive care unit predicts the need of dialysis in septic patients

Background

In a previous study we showed that troponin I (TnI) > 0.42 ng/mL predicted the need of dialysis in a group of 29 septic patients admitted to the intensive care unit (ICU). We aimed to confirm such finding in a larger independent sample.

Methods

All septic patients admitted to an ICU from March 2016 to February 2017 were included if age between 18 and 90 years, onset of sepsis < 24 h, normal left ventricular ejection fraction, and no previous coronary or kidney diseases. TnI was measured on day 1. Patients were followed by 30 days or until death.

Results

A total of 120 patients were included (51% male, 74 ± 13 years old). At ICU admission, 70 patients had TnI > 0.42 ng/mL. These patients had serum creatinine slightly higher (1.66 ± 0.34 vs. 1.32 ± 0.39 mg/dL; P <  0.0001) than those with lower TnI and similar urine output (1490 ± 682 vs. 1406 ± 631 mL; P = 0.44). At the end of the follow-up period, 70.0% of the patients with lower TnI were alive in comparison with 38.6% of those with higher TnI (p = 0.0014). After 30 days, 69.3 and 2.9% of the patients with lower and higher TnI levels remained free of dialysis, respectively (p <  0.0001). In a Cox regression model, after adjustment for gender, age, Charlson comorbidity index, serum creatinine, potassium, pH, brain natriuretic peptide and urine output, TnI > 0.42 ng/mL persisted as a strong predictor of dialysis need (hazard ratio 3.48 [95%CI 1.69–7.18]).

Conclusions

TnI levels at ICU admission are a strong independent predictor of dialysis need in sepsis.

Unrecognised myocardial infarction and its relationship to outcome in critically ill patients with cardiovascular disease

PURPOSE

To establish the incidence of myocardial infarction (MI) in ICU patients with co-existing cardiovascular disease (CVD), and explore its association with long-term survival.

METHODS

In a multi-centre prospective cohort study in 11 UK ICUs, we enrolled 273 critically ill patients with co-existing CVD. We measured troponin I (cTnI) with a high sensitivity assay for 10 days; ECGs were carried out daily for 5 days and analysed by blinded cardiologists for dynamic changes. Data were combined to diagnose myocardial 'infarction', 'injury' or 'no injury' according to the third universal definition of MI. Patients were followed-up for 6 months. Regression and mediation analyses were used to explore relationships between acute physiological derangements, MI, and mortality.

RESULTS

cTnI was detected in all patients, with a rise/fall pattern consistent with an acute hit. In 73% of patients, this peaked on days 1-3 [median 114 ng/l (first, third quartiles: 27, 393)]. Serial ECGs indicated 24.2% (n = 66) of patients experienced MI, but > 95% were unrecognized by clinical teams. Type 2 MI was the most likely aetiology in all cases. A further 46.1% (n = 126) experienced injury (no ECG changes). Injury and MI were both associated with 6-month mortality (reference: no injury): OR injury 2.28 (95% CI 1.06-4.92, p = 0.035), OR MI 2.70 (95% CI 1.11-6.55, p = 0.028). Mediation analysis suggested MI partially mediated the relationship between acute physiological derangement and 6-month mortality (p = 0.002), suggesting a possible causal association.

CONCLUSIONS

Undiagnosed MI occurs in around a quarter of critically ill patients with co-existing CVD and is associated with lower long-term survival.

Mortality in sepsis: Comparison of outcomes between patients with demand ischemia, acute myocardial infarction, and neither demand ischemia nor acute myocardial infarction

INTRODUCTION

Elevation in cardiac troponins is common with sepsis despite unclear impact.

HYPOTHESIS

We investigated whether demand ischemia(DI) resulted in variable outcomes compared to acute myocardial infarction(AMI) and those with neither DI nor AMI in sepsis.

METHODS

We analyzed data from the 2011-2014 National Inpatient Sample among patients admitted for sepsis. We compared outcomes among patients with DI i) versus AMI and ii) versus neither DI nor AMI, respectively using propensity matching. Primary study end-point was in-hospital mortality.

RESULTS

We studied 666,154 patients, with mean age 63.7 years and 50.8% female participants. Overall, 94.7% of the included patients had neither DI nor AMI, 4.4% had AMI and 0.83% had DI. Between 2011 and 2014, we observed an increasing trend for DI but decreasing trend for AMI in sepsis. Patients with DI experienced higher rates of atrial and ventricular arrhythmias, had longer length of stay and higher cost of stay compared to patients with neither demand ischemia nor AMI. Despite higher hospital mortality at baseline with DI, post-propensity matching revealed no difference in hospital mortality between patients with DI and those with neither (26.9% vs. 27.0%, adjusted odds ratio 0.99, 95% confidence intervals 0.92-1.07;p=0.87). Patients with DI experienced lower hospital mortality compared to those with AMI pre (28.5% vs. 48.3%;p<0.001) and post-propensity matching (41.1% vs. 29.1%, aOR 0.58, 95% CI 0.54-0.63;p<0.001).

CONCLUSION

Among patients with sepsis, those with DI had similar adjusted in-hospital mortality compared to those with neither DI nor AMI. Patients with AMI had the highest in-hospital mortality among all groups.

Cyanidin ameliorates endotoxin-induced myocardial toxicity by modulating inflammation and oxidative stress through mitochondria and other factors

Cyanidin, an anthocyanin pigment, demonstrates anti-oxidant and anti-inflammatory properties. Here, we examined the mechanistic role of cyanidin in endotoxin induced myocardial injury in inflammation and oxidative stress. In lipopolysaccharide (LPS) induced myocardial injury model, cyanidin ameliorated cardiac injury (Lactate dehydrogenase or LDH, Creatine Kinase or CK, cardiac troponin I or cTnI and cardiac myosin light chains 1 or cMLC1), cell death (caspase 3 activity and PARP activity), and improved cardiac function (ejection fraction or EF and end diastolic left ventricular inner dimension or LVID). Cyanidin also attenuated endotoxin induced myocardial injury by modulating inflammatory cytokines (Tumor necrosis factor alpha or TNFα, Interleukin-1 beta or IL-1β, macrophage inflammatory protein 2 or MIP-2 and chemokine (C-C motif) ligand 2 also known as monocyte chemoattractant protein 1 or MCP1) and oxidative stress (protein nitration). Cyanidin modulated redox homeostasis through intracellular oxidized/reduced glutathione. The most striking properties of cyanidin in endotoxin induced mediated myocardial injury was the modulation of mitochondria, its oxidative damage and associated factor Opa1 and Trx1. Thus, our study demonstrated that cyanidin as a constituent of our food chain may be beneficial and has therapeutic potential in sepsis treatment or other myocardial oxidative and/or inflammation induced injuries.

Determinants and prognosis of high-sensitivity cardiac troponin T peak plasma concentration in patients hospitalized for non-cardiogenic shock

Purpose:

The aim of this study was to assess the determinants and prognostic value of high-sensitivity cardiac troponin T peak plasma concentration in intensive care unit patients with non-cardiogenic shock.

Material and methods:

A prospective observational cohort study was conducted in a single intensive care unit between November 2014 and December 2015.

Results:

During the study period, 206 patients were hospitalized in the intensive care unit for non-cardiogenic shock and the median peak high-sensitivity cardiac troponin T was 55.1 [24.5–136] pg/mL. A multivariate analysis combining all variables showed that higher body mass index (t = 2.52, P = 0.01), lower left ventricular systolic function (t = −2.73, P = 0.007), higher white blood cell count (t = 3.72, P = 0.0001), lower creatinine clearance (t = −2.84, P = 0.0005), higher lactate level (t = 2.62, P = 0.01) and ST-segment depression (t = 3.98, P = 0.0001) best correlated with log₁₀-transformed high-sensitivity cardiac troponin T peak plasma concentration. After multivariate analysis, the high-sensitivity cardiac troponin T peak was not associated with a significant reduction of in-hospital mortality (adjusted odds ratio = 0.99 (95% confidence interval: 0.93–1.02)).

Conclusion:

High-sensitivity cardiac troponin T elevation was very common in patients hospitalized for non-cardiogenic shock. The factors significantly associated with high-sensitivity cardiac troponin T peak plasma concentration were higher body mass index, decreased left ventricular systolic ejection fraction, higher leucocyte count, decreased renal function, increased lactate level, and ST-segment depression. The high-sensitivity cardiac troponin T peak was not significantly associated with in-hospital mortality in this setting.

Resource utilization and outcome among patients with selective versus nonselective troponin testing

OBJECTIVE

In patients with suspected acute coronary syndrome (ACS), troponin testing is effective for diagnosis and prognosis. Troponin testing has now expanded to include patients without suspected ACS. This nonselective troponin testing has unknown consequences for resource utilization and outcome. Therefore, we examined selective versus nonselective troponin testing with respect to patient characteristics, resource utilization, and outcome.

METHODS

This retrospective 1-year study included all patients with troponin testing at a U.S. emergency department. Testing was classified as selective (ACS) or nonselective (non-ACS) based on admission ICD-9 codes. Troponin upper reference limit (URL) was ≥99th percentile.

RESULTS

Among 47,053 patients, troponin was measured in 9109 (19%) of whom 5764 were hospitalized. Admission diagnosis was non-ACS in 4427 (77%) and ACS in 1337 (23%). Non-ACS patients were older, 71±17 versus 65±16 years, with longer hospital stay, 77 versus 32 h, and greater 1-year mortality 22% versus 6.7%; P<.001. In patients with troponin ≥URL, revascularization was performed in 64 (4.7%) of non-ACS versus 213 (48%) of ACS; P<.001. In patients with troponin <URL, 1-year mortality was 16% in non-ACS versus 3.5% in ACS; P<.001. In those with troponin ≥URL, 1-year mortality was 35% in non-ACS versus 13% in ACS; P<.001. Death was non-cardiac in >80% of the non-ACS population CONCLUSIONS: Contemporary troponin testing is frequently nonselective. The non-ACS and ACS populations differ significantly regarding clinical characteristics, revascularization rates, and outcomes. Troponin elevation is a powerful predictor of 1-year mortality in non-ACS, this association reveals an opportunity for risk stratification and targeted therapy.

KEY QUESTIONS

In patients with suspected acute coronary syndrome (ACS), troponin testing is effective for diagnosis and prognosis. However, troponin testing has now expanded to include patients without suspected ACS. This nonselective troponin testing has unknown consequences for hospital resource utilization and patient outcome. Our findings demonstrate contemporary troponin testing is largely nonselective (77% of testing was performed in patients without acute coronary syndrome). In comparison to patients with acute coronary syndrome, those with non-acute coronary syndrome are older, with longer hospital stay, lower revascularization rates, and greater 1-year mortality. Troponin elevation identifies a high-risk population in both acute coronary syndrome and non-acute coronary syndrome populations, yet effective treatment for the latter is lacking.

Cardiac Troponin Release is Associated with Biomarkers of Inflammation and Ventricular Dilatation During Critical Illness

Introduction:

Troponin release is common during critical illness. We hypothesized that there was an association between cardiac troponin T (cTnT) and biomarkers of systemic inflammation and ventricular dilatation.

Methods:

In an observational prospective cohort study, we enrolled consecutive adult patients admitted for noncardiac reasons to the intensive care unit (ICU) in two tertiary care centers. We measured cTnT, C-reactive protein (CRP), interleukin-6 (IL-6), procalcitonin (PCT), and N-terminal pro brain natriuretic peptide (NT-proBNP) daily in the first week, and on alternate days in the second week. Using a peak cTnT cutoff ≥15 ng/L and concomitant changes on electrocardiogram, patients were categorized as “definite myocardial infarction (MI),” “possible MI,” “cTnT rise only,” or “no cTnT rise.” Within each group, associations between CRP, IL-6, PCT, NT-proBNP, and cTnT were investigated using mixed effect models.

Results:

One hundred seventy-two patients were included in the analysis of whom 84% had a cTnT rise ≥15 ng/L. Twenty-one patients (12%) had a definite MI, 51 (30%) had a possible MI, and 73 (42%) had a cTnT rise only. At the time of peak cTnT, 71% of patients were septic and 67% were on vasopressors.

Multivariable analysis showed a significant association between cTnT and IL-6 in all patients with a cTnT rise independent of age, gender, renal function, and cardiovascular risk factors. In patients without a definite MI, cTnT levels were significantly associated with PCT and NT-proBNP values. In patients without elevated cTnT levels, there was no associated NT-proBNP rise.

Conclusions:

In ICU patients admitted for non-cardiac reasons, serial cTnT levels were independently associated with markers of systemic inflammation and NT-proBNP.

Early structural changes of the heart after experimental polytrauma and hemorrhagic shock

Evidence is emerging that systemic inflammation after trauma drives structural and functional impairment of cardiomyocytes and leads to cardiac dysfunction, thus worsening the outcome of polytrauma patients. This study investigates the structural and molecular changes in heart tissue 4 h after multiple injuries with additional hemorrhagic shock using a clinically relevant rodent model of polytrauma. We determined mediators of systemic inflammation (keratinocyte chemoattractant, macrophage chemotactic protein 1), activated complement component C3a and cardiac troponin I in plasma and assessed histological specimen of the mouse heart via standard histomorphology and immunohistochemistry for cellular and subcellular damage and ongoing apoptosis. Further we investigated spatial and quantitative changes of connexin 43 by immunohistochemistry and western blotting. Our results show significantly increased plasma levels of both keratinocyte chemoattractant and cardiac troponin I 4 h after polytrauma and 2 h after induction of hypovolemia. Although we could not detect any morphological changes, immunohistochemical evaluation showed increased level of tissue high-mobility group box 1, which is both a damage-associated molecule and actively released as a danger response signal. Additionally, there was marked lateralization of the cardiac gap-junction protein connexin 43 following combined polytrauma and hemorrhagic shock. These results demonstrate a molecular manifestation of remote injury of cardiac muscle cells in the early phase after polytrauma and hemorrhagic shock with marked disruption of the cardiac gap junction. This disruption of an important component of the electrical conduction system of the heart may lead to arrhythmia and consequently to cardiac dysfunction.

Severe Pneumococcal Pneumonia Causes Acute Cardiac Toxicity and Subsequent Cardiac Remodeling

RATIONALE

Up to one-third of patients hospitalized with pneumococcal pneumonia experience major adverse cardiac events (MACE) during or after pneumonia. In mice, Streptococcus pneumoniae can invade the myocardium, induce cardiomyocyte death, and disrupt cardiac function following bacteremia, but it is unknown whether the same occurs in humans with severe pneumonia.

OBJECTIVES

We sought to determine whether S. pneumoniae can (1) translocate the heart, (2) induce cardiomyocyte death, (3) cause MACE, and (4) induce cardiac scar formation after antibiotic treatment during severe pneumonia using a nonhuman primate (NHP) model.

METHODS

We examined cardiac tissue from six adult NHPs with severe pneumococcal pneumonia and three uninfected control animals. Three animals were rescued with antibiotics (convalescent animals). Electrocardiographic, echocardiographic, and serum biomarkers of cardiac damage were measured (troponin T, N-terminal pro-brain natriuretic peptide, and heart-type fatty acid binding protein). Histological examination included hematoxylin and eosin staining, immunofluorescence, immunohistochemistry, picrosirius red staining, and transmission electron microscopy. Immunoblots were used to assess the underlying mechanisms.

MEASUREMENTS AND MAIN RESULTS

Nonspecific ischemic alterations were detected by electrocardiography and echocardiography. Serum levels of troponin T and heart-type fatty acid binding protein were increased (P < 0.05) after pneumococcal infection in both acutely ill and convalescent NHPs. S. pneumoniae was detected in the myocardium of all NHPs with acute severe pneumonia. Necroptosis and apoptosis were detected in the myocardium of both acutely ill and convalescent NHPs. Evidence of cardiac scar formation was observed only in convalescent animals by transmission electron microscopy and picrosirius red staining.

CONCLUSIONS

S. pneumoniae invades the myocardium and induces cardiac injury with necroptosis and apoptosis, followed by cardiac scarring after antibiotic therapy, in an NHP model of severe pneumonia.

Role of Admission Troponin-T and Serial Troponin-T Testing in Predicting Outcomes in Severe Sepsis and Septic Shock

BACKGROUND

Troponin-T elevation is seen commonly in sepsis and septic shock patients admitted to the intensive care unit. We sought to evaluate the role of admission and serial troponin-T testing in the prognostication of these patients.

METHODS AND RESULTS

This was a retrospective cohort study from 2007 to 2014 on patients admitted to the intensive care units at the Mayo Clinic with severe sepsis and septic shock. Elevated admission troponin-T and significant delta troponin-T were defined as ≥0.01 ng/mL and ≥0.03 ng/mL in 3 hours, respectively. The primary outcome was in-hospital mortality. Secondary outcomes included 1-year mortality and lengths of stay. During this 8-year period, 944 patients met the inclusion criteria with 845 (90%) having an admission troponin-T ≥0.01 ng/mL. Serial troponin-T values were available in 732 (78%) patients. Elevated admission troponin-T was associated with older age, higher baseline comorbidity, and severity of illness, whereas significant delta troponin-T was associated with higher severity of illness. Admission log10 troponin-T was associated with unadjusted in-hospital (odds ratio 1.6; P=0.003) and 1-year mortality (odds ratio 1.3; P=0.04), but did not correlate with length of stay. Elevated delta troponin-T and log10 delta troponin-T were not significantly associated with any of the primary or secondary outcomes. Admission log10 troponin-T remained an independent predictor of in-hospital mortality (odds ratio 1.4; P=0.04) and 1-year survival (hazard ratio 1.3; P=0.008).

CONCLUSIONS

In patients with sepsis and septic shock, elevated admission troponin-T was associated with higher short- and long-term mortality. Routine serial troponin-T testing did not add incremental prognostic value in these patients.

Downregulation of PI3K-γ in a mouse model of sepsis-induced myocardial dysfunction

A key component during sepsis is the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, of which the PI3K-γ isoform is a major regulator in many inflammatory responses. However, the role of PI3K-γ in the development of sepsis-induced myocardial dysfunction (SIMD) is unknown. In this study, we established a model of SIMD induced by lipopolysaccharide (LPS), subsequently used the selective inhibitor LY294002 and AS605240 to block the effect of PI3K and PI3K-γ, respectively. Cardiac function was evaluated by echocardiography, hearts were obtained for histological and protein expression examinations. ELISA was used to measure the serum levels of tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), cardiac troponin I (cTnI) and heart-type fatty acid binding protein (H-FABP). LPS-treated mice showed an increase to cardiac inflammation, myocardial damage and production of TNF-α, IL-6, NF-κB, cTnI and H-FABP. Administration of AS605240 to LPS-treated mice reduced some patho-physiological characteristics of SIMD and reduced TNF-α, IL-6, cTnI and H-FABP production. However, administration of LY294002 did not improve those same conditions. The results showed that PI3K-γ is likely a crucial element in SIMD by regulating the PI3K/Akt pathway, and become a new marker of myocardial injury. Inhibition of PI3K-γ might be a potential therapeutic target in SIMD.

Pattern and consequences of cardiologic medications management for patients with elevated troponin I upon admission into an intensive care unit not linked to type 1 acute myocardial infarction: A prospective observational cohort study

OBJECTIVES

No recommendations are currently available to help the clinician with the pharmacological management of intensive care unit (ICU) patients with elevated cardiac troponin (cTn) not linked to type 1 AMI. The aim of this study was to evaluate the pattern of cardiologic medications for patients with elevated cTnI in ICU not link to type 1 AMI and their effects on in-hospital mortality.

MATERIAL AND METHODS

A prospective observational cohort study conducted in two ICU units. Patients with increased plasma concentration of cTnI at admission not linked to type 1 AMI were consecutively included.

RESULTS

One hundred and ninety of the 835 patients admitted (23%) had an increased plasma concentration of cTnI not related to type 1 AMI. Antiplatelet therapy (AT) and statin were prescribed in 56 (29.5%) and 50 (26.3%) of patients, respectively. Others cardiologic medications were prescribed in less than 5% of all cases and were considered as contraindicated in more than 50% of cases. Antiplatelet therapy was the only cardiologic treatment associated with reduction of in-hospital mortality following uni- and multivariate analysis. The death rate was 23% and 40% in these patients treated with and without AT, respectively (aOR=0.39 [95% CI: 0.15-0.97]).

CONCLUSIONS

Statin and AT were frequently prescribed to patients with a cTnI elevation not linked to type 1 AMI. This study suggests that AT in patients with an increased plasma concentration of cTnI, not related to type 1 AMI in ICU, could reduce in-hospital mortality.

Postoperative Infections are Associated with Increased Risk of Cardiac Events in Vascular Patients

BACKGROUND

Despite advances in perioperative care, the rate of cardiac events in vascular patients remains high. We have previously shown that infections in trauma patients are associated with higher rates of subsequent cardiac complications, likely due to the additive effect of a second hit of an infection following the trauma. The aim of this study was to investigate whether there is an association between postoperative infections and subsequent cardiac events in vascular patients.

METHODS

A 5-year retrospective review of demographics, comorbidities, operative interventions, infectious, and cardiac events in all vascular patients who underwent an operative intervention at a single tertiary referral center was performed. In patients with clinical suspicion of myocardial injury, myocardial damage was defined as troponin >0.15 ng/mL and myocardial infarction (MI) as troponin >1 ng/mL. Pneumonia was diagnosed using bronchoalveolar lavage (BAL) and considered positive if BAL fluid culture contained >10,000 colony-forming units (cfu). Urinary tract infection (UTI) was diagnosed if the urine culture contained >100,000 cfu. All other infections were diagnosed by culture data. Regression analysis was performed to assess risk of cardiac events as a function of infections adjusting for age, gender, and comorbidities.

RESULTS

We analyzed 1,835 vascular operative interventions with the mean age of the cohort 65.5 years (65.9% male). The overall infection rate was 13.2%, with UTI being the most common (60.3%). The overall rate of myocardial damage was 8.1% and the rate of MI 3.8%. Rates of both myocardial damage (15.5 vs. 7.7%; P = 0.0015) and MI (7.1 vs. 3.4%; P = 0.018) were significantly higher in patients with infections, compared to those without infections. Adjusting for age, gender, medical comorbidities, open versus endovascular cases as well as statin and steroid use, patients with UTI were more likely to subsequently develop either myocardial damage (odds ratio [OR] = 3.57 [95% confidence interval = 1.51-8.45]) or MI (OR = 4.20 [1.23-14.3]). A similar association was noted between any infections and either myocardial damage (OR = 2.97 [1.32-6.65]) or MI (OR = 4.31 [1.44-12.94]).

CONCLUSIONS

We herein describe an association between postoperative infections, most commonly UTI, and subsequent cardiac events. Efforts should be made to minimize the risk of developing infections to ensure cardioprotection in vascular patients during perioperative period.

Elevation of NT-proBNP and cardiac troponins in sepsis-related deaths: a forensic perspective

In the present study, the levels of NT-proBNP, troponin T, and troponin I were measured in postmortem serum from femoral blood in a series of sepsis-related fatalities that had undergone forensic autopsies. We aimed to assess whether a possible increase in the concentrations of these biomarkers was correlated to macroscopic or microscopic observations that suggest myocardial damage or cardiac dysfunction. Two study groups were retrospectively formed, a sepsis-related fatalities group and a control group. Both groups consisted of 16 forensic autopsy cases. Unenhanced computed tomography scan, autopsy, histological, toxicological, microbiological, and biochemical analyses were performed for all cases in both groups. Levels of procalcitonin, C-reactive protein, NT-proBNP, troponin T, and troponin I were systematically measured in postmortem serum from femoral blood. The preliminary results suggest that the postmortem serum troponin I, troponin T, and NT-proBNP levels are increased in sepsis-related deaths in the absence of any relevant coronary artery disease, myocardial ischemia, or signs of heart failure. These findings corroborate clinical data from previous studies pertaining to the usefulness of troponins and natriuretic peptides as indicators of toxic and inflammatory damage to the heart in cases of severe sepsis and septic shock without concomitant underlying coronary syndromes.

Obstructive coronary artery disease in patients hospitalized for severe sepsis or septic shock with concomitant acute myocardial infarction

PURPOSE

It is difficult to differentiate type 1 acute myocardial infarction (AMI) with obstructive coronary artery disease (OCAD) from type 2 AMI in patients admitted for severe sepsis. The aims of this study were to assess the risk factors and prognosis of OCAD in patients admitted to the intensive care unit for severe sepsis with concomitant AMI.

MATERIALS AND METHODS

This is a single-center retrospective cohort study including all consecutive patients who were hospitalized for severe sepsis or septic shock between March 2006 and September 2014 and who underwent coronary angiography in the intensive care unit to identify AMI.

RESULTS

Overall, 78 (5.5%) of 1418 patients hospitalized for severe sepsis underwent coronary angiography to identify concomitant AMI. Thirty-two patients (41%) had OCAD. Following multivariate analysis, the risk factors of OCAD were peripheral vascular disease (odds ratio [OR] =5.7; 95% confidence interval [CI], 1.1-30.4; P = .042) and at least 2 cardiovascular risk factors (OR = 6.7; 95% CI, 1.9-23.8; P = .003). Obstructive coronary artery disease was associated with a significant mortality increase at 60 days (OR = 8.1; 95% CI, 1.9-30.2; P = .004).

CONCLUSIONS

Obstructive coronary artery disease is a poor prognosis factor in patients hospitalized for severe sepsis with concomitant AMI. In this setting, medical treatment should be considered for patients with peripheral vascular disease or with at least 2 cardiovascular risk factors; the need to perform coronary angiography should be considered carefully.

Cardiac Troponins in Dogs and Cats

Cardiac troponins are sensitive and specific markers of myocardial injury. The troponin concentration can be thought of as a quantitative measure of the degree of injury sustained by the heart, however, it provides no information on the cause of injury or the mechanism of troponin release. Conventionally, the cardiac troponins have been used for diagnosis of acute myocardial infarction in humans and have become the gold standard biomarkers for this indication. They have become increasingly recognized as an objective measure of cardiomyocyte status in both cardiac and noncardiac disease, supplying additional information to that provided by echocardiography and ECG. Injury to cardiomyocytes can occur through a variety of mechanisms with subsequent release of troponins. Independent of the underlying disease or the mechanism of troponin release, the presence of myocardial injury is associated with an increased risk of death. As increasingly sensitive assays are introduced, the frequent occurrence of myocardial injury is becoming apparent, and our understanding of its causes and importance is constantly evolving. Presently troponins are valuable for detecting a subgroup of patients with higher risk of death. Future research is needed to clarify whether troponins can serve as monitoring tools guiding treatment, whether administering more aggressive treatment to patients with evidence of myocardial injury is beneficial, and whether normalizing of troponin concentrations in patients presenting with evidence of myocardial injury is associated with reduced risk of death.

Diagnosis and management of type II myocardial infarction: increased demand for a limited supply of evidence

Type 2 myocardial infarction (type 2 MI) is defined as myocardial necrosis that results from an imbalance of myocardial oxygen supply and demand. Although type 2 MI is highly prevalent and strongly associated with mortality, the pathophysiology remains poorly understood. Discrepancies in definitions, frequency of screening, diagnostic approaches, and methods of adjudication lead to confusion and misclassification. To date, there is no consensus on the diagnostic criteria for type 2 MI. No guidelines exist for the optimal management of this condition, and further investigation is urgently needed. This review explores the existing evidence on the pathophysiology, diagnosis, prognosis, and management of type 2 MI.

Raised cardiac troponin in intensive care patients with sepsis, in the absence of angiographically documented coronary artery disease: A systematic review

Elevated cardiac troponin in the critically ill has been associated with increased hospital mortality. However, in critically ill patients with sepsis the results are heterogeneous and less easy to interpret. The objectives of this systematic review were to describe the pathophysiology, clinical relevance and prognostic significance of raised troponin in intensive care patients with sepsis. Articles were identified through a detailed MEDLINE search and additional references were retrieved from the selected studies. A growing body of clinical evidence suggests that although troponins are sensitive biomarkers with prognostic value, they are not independent predictors of mortality. However, vigilance for objective evidence of coronary artery disease is required and patients with atherosclerotic risk factors and elevated troponins may benefit from cardiac imaging. In patients with low pre-test probability for coronary artery disease and elevated troponins, therapy should target management of sepsis and optimisation of myocardial oxygen demand/supply balance.

High-sensitivity cardiac troponin for risk prediction in patients with and without coronary heart disease

BACKGROUND

In stable patients with unknown coronary anatomy, higher levels of cardiac troponin are associated with an increased risk of cardiovascular events. It was supposed that this association might be explained by the ability of cardiac troponin to detect minor myocardial necrosis which might be caused by subclinical coronary atherosclerosis. Thus, this analysis tested if the predictive value of high-sensitivity troponin T (hsTnT) in stable patients is dependent of the presence or absence of angiographically documented coronary heart disease.

METHODS

Stable patients undergoing elective coronary angiography were enrolled (n=2046). HsTnT was determined before diagnostic procedures. The patients were followed for up to seven years. Primary endpoint was all-cause mortality or non-fatal myocardial infarction. All endpoints were adjudicated by independent physicians. Results were adjusted to a clinical model including independent clinical predictors of the primary endpoint.

RESULTS

Out of the 2046 patients enrolled, 1236 (60%) had a diagnosis of obstructive coronary heart disease. HsTnT predicted independently the primary endpoint (adjusted HR 1.33, 95%-CI 1.21-1.46, P<0.001). The use of hsTnT in addition to the clinical model significantly improved discrimination (c-statistic: 0.751 to 0.773, P<0.001) as well as reclassification of the primary endpoint (NRI=0.362, P<0.001). This significant improvement persisted across various subsets and was independent of the presence of clinically detectable coronary heart disease and other variables.

CONCLUSION

The use of hsTnT in addition to clinical variables significantly improves discrimination and reclassification of patients with respect to all-cause mortality or non-fatal myocardial infarction irrespective of the presence of clinically detectable coronary heart disease.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov (Identifier: NCT00457236).

Perioperative cardiac biomarkers: the utility and timing

PURPOSE OF REVIEW

We presume that biomarkers will improve identification of patients at risk, leading to interventions and treatments that reduce perioperative adverse events. Risk stratification is multifactorial, and a biomarker must add information to this process, thereby redistributing patients to either higher or lower risk categories, to improve the allocation of expensive and risky interventions. This review focuses on the utility of three cardiac biomarkers in perioperative management.

RECENT FINDINGS

Using newly defined epidemiologic criteria, three distinct molecules, brain natriuretic peptide (BNP), troponin (cTn), and glycosylated hemoglobin (HbA1c) emerge as potentially useful in perioperative medicine. A meta-analysis shows, in vascular surgery, BNP improves risk stratification. Four articles highlight the utility of postoperative cTn measurements in cases of myocardial injury. These articles show that most injury is not infarction, and they present preliminary evidence of the populations that will benefit from structured surveillance protocols. HbA1c is shown to improve the prediction of mortality, but there are questions whether this risk is modifiable.

SUMMARY

The findings here suggest an expanded role for postoperative cTn surveillance; however, the precise populations that benefit, or the interventions required, are not yet defined. The encouraging data for the other two biomarkers need more investigations before adopting them into routine clinical use.

Utility of thromboelastography and/or thromboelastometry in adults with sepsis: a systematic review

Introduction

Coagulation abnormalities are frequent in sepsis. Conventional coagulation assays, however, have several limitations. A surge of interest exists in the use of point-of-care tests to diagnose hypo- and hypercoagulability in sepsis.

We performed a systematic review of available literature to establish the value of rotational thromboelastography (TEG) and thromboelastometry (ROTEM) compared with standard coagulation tests to detect hyper- or hypocoagulability in sepsis patients. Furthermore, we assessed the value of TEG/ROTEM to identify sepsis patients likely to benefit from therapies that interfere with the coagulation system.

Methods

MEDLINE, EMBASE, and the Cochrane Library were searched from 1 January 1980 to 31 December 2012. The search was limited to adults, and language was limited to English. Reference lists of retrieved articles were hand-searched for additional studies. Ongoing trials were searched on http://www.controlled-trials.com and http://www.clinicaltrials.gov. Studies addressing TEG/ROTEM measurements in adult patients with sepsis admitted to the ICU were considered eligible.

Results

Of 680 screened articles, 18 studies were included, of which two were randomized controlled trials, and 16 were observational cohort studies. In patients with sepsis, results show both hyper- and hypocoagulability, as well as TEG/ROTEM values that fell within reference values. Both hyper- and hypocoagulability were to some extent associated with diffuse intravascular coagulation. Compared with conventional coagulation tests, TEG/ROTEM can detect impaired fibrinolysis, which can possibly help to discriminate between sepsis and systemic inflammatory response syndrome (SIRS). A hypocoagulable profile is associated with increased mortality. The value of TEG/ROTEM to identify patients with sepsis who could possibly benefit from therapies interfering with the coagulation system could not be assessed, because studies addressing this topic were limited.

Conclusion

TEG/ROTEM could be a promising tool in diagnosing alterations in coagulation in sepsis. Further research on the value of TEG/ROTEM in these patients is warranted. Given that coagulopathy is a dynamic process, sequential measurements are needed to understand the coagulation patterns in sepsis, as can be detected by TEG/ROTEM.

Prognostic importance of myocardial injury in critically ill dogs with systemic inflammation

BACKGROUND

In noncardiac critical disease in humans, myocardial injury as detected by cardiac troponin I and T (cTnI and cTnT) has been linked to high intensive care unit (ICU) death independent of prognostic composite scoring.

HYPOTHESIS

Presence of myocardial injury predicts short-term death in critically ill dogs with systemic inflammation and provides additional prognostic information when combined with established canine prognostic composite scores.

ANIMALS

Forty-two dogs admitted to the ICU with evidence of systemic inflammation and no primary cardiac disease.

METHODS

Prospective cohort study. Blood samples were obtained at ICU admission for the measurement of cTnI and cTnT, C-reactive protein, and several cytokines. The acute patient physiologic and laboratory evaluation (APPLE) score and the survival prediction index were calculated within the first 24 hours of admission. Receiver operating characteristic (ROC) curves were used to examine the prognostic capacity of each biomarker and severity score. Multiple logistic regression analysis was performed to evaluate whether cardiac markers significantly contributed to severity scores.

RESULTS

Twenty-eight day case fatality rate was 26% (11/42 dogs). cTnI concentrations were (median [range]) 0.416 [0.004-141.5] ng/mL and cTnT concentrations were 13.5 [<13-3,744] ng/L. cTnI, cTnT, and the APPLE score were all significant prognosticators with areas under the ROC curves [95% CI] of 0.801 [0.649; 0.907], 0.790 [0.637; 0.900], and 0.776 [0.621; 0.889], respectively. cTnI significantly contributed to the APPLE score in providing additional prognostic specificity (P = .025).

CONCLUSIONS AND CLINICAL IMPORTANCE

Markers of myocardial injury predict short-term death in dogs with systemic inflammation and cTnI significantly contributes to the APPLE score.

Prognostic value of troponins in sepsis: a meta-analysis

RATIONALE

The role of biomarkers such as troponin in risk stratification of sepsis is still debated. The aim of this meta-analysis is to assess the relation between troponin elevation in sepsis and mortality.

METHODS

All observational studies from Embase, Medline and those manually searched up to September 2010 were included. Studies identified were those which reported on patients with a diagnosis of sepsis and if a 2 × 2 table could be constructed based on troponins and death. We pooled the relative risk (RR) and odds-ratio (OR) using the inverse variance method in studies that conducted univariate and multivariable (adjusted) analysis.

MAIN RESULTS

Thirteen studies encompassing 1,227 patients were included. The prevalence of elevated troponin was 61 % ([95 %] CI 58-64 %). Elevated troponin was significantly associated with all-cause mortality (RR 1.91; CI 1.63-2.24), with homogeneity across studies. In adjusted analysis (four studies comprising 791 patients) according to prognostic scores, elevated troponin was associated with an increased risk of death (OR 1.92; CI 1.35-2.74). The area under the ROC curve was 0.68 (CI 0.63-0.71). Pooled sensitivity and specificity were 77 % (CI 61-88) and 47 % (CI 30-64) with heterogeneity across studies. It corresponded to positive and negative likelihood ratios of 1.50 (95 % CI: 1.20-1.90) and 0.49 (CI 0.38-0.64), respectively.

CONCLUSIONS

Elevated troponin identifies a subset of patients with sepsis at higher risk of death. Further studies are needed to define the precise role of troponins and their optimal cut-offs.

Elevated cardiac troponins in setting of systemic inflammatory response syndrome, sepsis, and septic shock

Elevation of cardiac troponins and creatinine kinase is frequently observed in setting of systemic inflammatory response syndrome (SIRS), sepsis, or septic shock. Underlying pathophysiologic mechanism for such troponin leak, its clinical significance, and what different could be done in such settings remain elusive. In this paper we have briefly overviewed the proposed pathogenic mechanisms for SIRS, sepsis, or septic shock-related troponin elevation (SRTE) and have provided brief overview on its clinical significance. Upon review of the relevant literature we found that majority of patients with the SRTE with no prior history of coronary artery disease (CAD) upon testing are found not to have any CADs. We have also briefly discussed the possible pharmacologic agents and potential targets which are important from pathophysiologic and pharmacologic point of view that may alter the outcomes of SRTE-related myocardial depression in near future.