Elevated troponin in septic patients in the emergency department: frequency, causes, and prognostic implications

[Septic cardiomyopathy-diagnosis and estimation of disease severity]

BACKGROUND

The relevance of septic cardiomyopathy is frequently underestimated due to the complexity of the pattern of cardiac injury and the corresponding difficulties in quantifying the degree of functional impairment.

AIM

Account of the methods for diagnosis and severity classification of septic cardiomyopathy.

METHODS

Literature review and analysis of the main findings.

RESULTS

Septic cardiomyopathy is characterized by both systolic and diastolic impairment of not only the left, but also the right ventricle, as well as by sinus-tachycardiomyopathy (≥ 90-95 beats/min) of variable degree. Sepsis-related organ failure assessment (SOFA) score, left ventricular ejection fraction (LVEF), ECG and cardiac biomarkers do not help in grading severity of septic cardiomyopathy. For that purpose either a sophisticated echocardiography diagnosis is mandatory, or the measurement of those global heart function parameters which take into account the dependency of cardiac output on afterload, in view of the pronounced vasodilatation in sepsis and septic shock, is needed. A suitable parameter on the basis of cardiac output measurement is afterload-related cardiac performance (ACP), which gives the percentage of cardiac output in a septic patient related to the cardiac output a healthy heart pumps when challenged by a fall in systemic vascular resistance to the same extent. The calculation of ACP shows that at least one in two septic patients suffers from impaired heart function and that mortality increases as severity increases.

CONCLUSION

Simple parameters like LVEF are not apt for diagnosis nor for disease severity classification of septic cardiomyopathy. For that purpose either sophisticated echocardiography techniques or load-independent parameters-best validated-ACP measurements are appropriate.

Desmoglein-2 and COVID-19 complications: insights into its role as a biomarker, pathogenesis and clinical implications

Desmoglein-2 (DSG2) has emerged as a potential biomarker for coronavirus disease 2019 (COVID-19) complications, particularly cardiac and cardiovascular involvement. The expression of DSG2 in lung tissues has been detected at elevated levels, and circulating DSG2 levels correlate with COVID-19 severity. DSG2 may contribute to myocardial injury, cardiac dysfunction and vascular endothelial dysfunction in COVID-19. Monitoring DSG2 levels could aid in risk stratification, early detection and prognostication of COVID-19 complications. However, further research is required to validate DSG2 as a biomarker. Such research will aim to elucidate its precise role in pathogenesis, establishing standardized assays for its measurement and possibly identifying therapeutic targets.

Associations between elevated high-sensitive cardiac troponin t and outcomes in patients with acute abdominal pain

PURPOSE

The purpose of this study was to determine outcomes in patients presenting to emergency department (ED) with acute abdominal pain and suspected occult myocardial injury [OMI (high-sensitive cardiac troponin T, hs-cTnT level > 14 ng/L)] without clinical signs of myocardial ischaemia. We hypothesized that OMI is a common entity associated with poor outcomes.

METHODS

After institutional research ethics committee approval, a retrospective review was performed on patients subjected to extended use of hs-cTnT measurements during two months period in patients admitted to ED with a chief complaint of abdominal pain, aged 30 years or older and triaged to red, orange, or yellow categories. Primary outcomes were 30-day, six-month, and one-year mortality, respectively. Adjusted mortality rates were compared using the Cox proportional hazard regression model.

RESULTS

Overall, 1000 consecutive patients were screened. A total of 375 patients were subjected to hs-cTnT measurement and 156 of them (41.6%) experienced OMI. None of the patients had acute myocardial infarction diagnosed in the ED. Patients with OMI had a significantly higher 30-day, six-month and one-year mortality compared to the normal hs-cTnT level group [12.8% (20/156) vs. 3.7% (8/219), p = 0.001, 34.0% (53/156) vs. 6.9% (15/219), p < 0.001 and 39.1% (61/156) vs. 9.1 (20/219), p < 0.001, respectively]. OMI was an independent risk factor for mortality at every time point analyzed.

CONCLUSION

Our investigation noted OMI in older patients with co-morbidities and in higher triage category presenting with abdominal pain to ED, respectively. OMI is an independent risk factor for poor outcomes that warrants appropriate screening and management strategy. Our results support the use of hs-cTnT as a prognostication tool in this subgroup of ED patients.

Diagnostic Role and Methods of Detection of Cardiac Troponins: An Opinion from Historical and Current Points of View

The laboratory methods for the determination of cardiac troponins (cTnI, cTnT) used nowadays are extremely diverse, which has a significant impact on our understanding of the biology and diagnostic the value of cTnI and cTnT as biomarkers. The main classification of methods for the determination of cTnI and cTnT is based on the sensitivity of the immunoassay. Low- and moderately sensitive detection methods are known to be relatively less sensitive, which leads to a relatively late confirmation of cardiomyocyte death. Due to the new highly sensitive methods used to determine cTnI and cTnT, designated as a highly or ultrasensitive immunoassays (hs-TnT and hs-TnT), we received new, revised data about the biology of cardiac troponin molecules. In particular, it became clear that they can be considered products of normal myocardium metabolism since hs-TnT and hs-TnT are detected in almost all healthy patients. It also turned out that hs-TnT and hs-TnT differ by gender (in men, troponin concentration in the blood is higher than in women), age (in elderly patients, the levels of troponins are higher than in young ones) and circadian cycles (morning concentrations of troponins are higher than in the evening). A large variety of methods for determining cTnI and cTnT, differing in their diagnostic capabilities, creates the need for tests to perform an unbiased assessment of the analytical characteristics of each method. This review focuses on the most pressing issues related to the discussion of the biological characteristics of cardiac troponin and the analytical characteristics of troponin immunoassays from a historical and contemporary point of view.

Recombinant thrombomodulin may protect cardiac capillary endothelial glycocalyx through promoting Glypican-1 expression under experimental endotoxemia

Introduction

Myocardial dysfunction occurs in patients with sepsis due to vascular endothelial injury. Recombinant human thrombomodulin (rhTM) attenuates vascular endothelial injuries through endothelial glycocalyx (eGC) protection.

Hypothesis

We hypothesized that rhTM attenuates myocardial dysfunction via the inhibition of vascular endothelial injury during sepsis.

Methods

Ten-week-old male C57BL6 mice were injected intraperitoneally with 20 mg/kg of lipopolysaccharide (LPS). In rhTM-treated mice, rhTM was injected intraperitoneally at 3 and 24 h after LPS injection. Saline was injected intraperitoneally as control. To assess for eGC injury, intensity score was measured 48 h after the LPS injection. To confirm vascular endothelial injuries, ultrastructural analysis was performed using scanning (SEM) and transmission electron microscopy (TEM).

Results

The survival rate of the rhTM group at 48 h after LPS injection was significantly higher than that of the control group (68% vs. 17%, p < 0.05). The serum level of troponin I in the rhTM group was lower than that in the control (2.2 ± 0.4 ng/dL vs 9.4 ± 1.1 ng/dL, p < 0.05). The expression of interleukin-6 (IL-6) was attenuated in the rhTM-treated group than in the control (65.3 ± 15.3 ng/mL vs 226.3 ± 19.4 ng/mL, p < 0.05). The serum concentration of syndecan-1, a marker of glycocalyx damage, was significantly decreased 48 h post-administration of LPS in the rhTM-treated group than in the control group. In ultrastructural analysis using SEM and TEM, eGC peeled off from the surface of the capillary lumen in the control. Conversely, the eGC injury was attenuated in the rhTM group. Gene set enrichment analysis revealed that osteomodulin, osteoglycin proline/arginine-rich end leucine-rich repeat protein, and glypican-1, which are proteoglycans, were preserved by rhTM treatment. Their protein expression was retained in endothelial cells.

Conclusion

rhTM attenuates sepsis-induced myocardial dysfunction via eGC protection.

A review of cardiac troponin I detection by surface enhanced Raman spectroscopy: Under the spotlight of point-of-care testing

Cardiac troponin I (cTnI) is a biomarker widely related to acute myocardial infarction (AMI), one of the leading causes of death around the world. Point-of-care testing (POCT) of cTnI not only demands a short turnaround time for its detection but the highest accuracy levels to set expeditious and adequate clinical decisions. The analytical technique Surface-enhanced Raman spectroscopy (SERS) possesses several properties that tailor to the POCT format, such as its flexibility to couple with rapid assay platforms like microfluidics and paper-based immunoassays. Here, we analyze the strategies used for the detection of cTnI by SERS considering POCT requirements. From the detection ranges reported in the reviewed literature, we suggest the diseases other than AMI that could be diagnosed with this technique. For this, a section with information about cardiac and non-cardiac diseases with cTnI release, including their release kinetics or cut-off values are presented. Likewise, POCT features, the use of SERS as a POCT technique, and the biochemistry of cTnI are discussed. The information provided in this review allowed the identification of strengths and lacks of the available SERS-based point-of-care tests for cTnI and the disclosing of requirements for future assays design.

Metabolic Pathway of Cardiospecific Troponins: From Fundamental Aspects to Diagnostic Role (Comprehensive Review)

Many molecules of the human body perform key regulatory functions and are widely used as targets for the development of therapeutic drugs or as specific diagnostic markers. These molecules undergo a significant metabolic pathway, during which they are influenced by a number of factors (biological characteristics, hormones, enzymes, etc.) that can affect molecular metabolism and, as a consequence, the serum concentration or activity of these molecules. Among the most important molecules in the field of cardiology are the molecules of cardiospecific troponins (Tns), which regulate the processes of myocardial contraction/relaxation and are used as markers for the early diagnosis of ischemic necrosis of cardiomyocytes (CMC) in myocardial infarction (MI). The diagnostic value and diagnostic capabilities of cardiospecific Tns have changed significantly after the advent of new (highly sensitive (HS)) detection methods. Thus, early diagnostic algorithms of MI were approved for clinical practice, thanks to which the possibility of rapid diagnosis and determination of optimal tactics for managing patients with MI was opened. Relatively recently, promising directions have also been opened for the use of cardiospecific Tns as prognostic markers both at the early stages of the development of cardiovascular diseases (CVD) (arterial hypertension (AH), heart failure (HF), coronary heart disease (CHD), etc.), and in non-ischemic extra-cardiac pathologies that can negatively affect CMC (for example, sepsis, chronic kidney disease (CKD), chronic obstructive pulmonary disease (COPD), etc.). Recent studies have also shown that cardiospecific Tns are present not only in blood serum, but also in other biological fluids (urine, oral fluid, pericardial fluid, amniotic fluid). Thus, cardiospecific Tns have additional diagnostic capabilities. However, the fundamental aspects of the metabolic pathway of cardiospecific Tns are definitively unknown, in particular, specific mechanisms of release of Tns from CMC in non-ischemic extra-cardiac pathologies, mechanisms of circulation and elimination of Tns from the human body, mechanisms of transport of Tns to other biological fluids and factors that may affect these processes have not been established. In this comprehensive manuscript, all stages of the metabolic pathway are consistently and in detail considered, starting from release from CMC and ending with excretion (removal) from the human body. In addition, the possible diagnostic role of individual stages and mechanisms, influencing factors is analyzed and directions for further research in this area are noted.

The Importance of Cardiac Troponin Metabolism in the Laboratory Diagnosis of Myocardial Infarction (Comprehensive Review)

The study of the metabolism of endogenous molecules is not only of great fundamental significance but also of high practical importance, since many molecules serve as drug targets and/or biomarkers for laboratory diagnostics of diseases. Thus, cardiac troponin molecules have long been used as the main biomarkers for confirmation of diagnosis of myocardial infarction, and with the introduction of high-sensitivity test methods, many of our ideas about metabolism of these cardiac markers have changed significantly. In clinical practice, there are opening new promising diagnostic capabilities of cardiac troponins, the understanding and justification of which are closely connected with the fundamental principles of the metabolism of these molecules. Our current knowledge about the metabolism of cardiac troponins is insufficient and extremely disconnected from various literary sources. Thus, many researchers do not sufficiently understand the potential importance of cardiac troponin metabolism in the laboratory diagnosis of myocardial infarction. The purpose of this comprehensive review is to systematize information about the metabolism of cardiac troponins and during the discussion to focus on the potential impact of cTns metabolism on the laboratory diagnosis of myocardial infarction. The format of this comprehensive review includes a sequential consideration and analysis of the stages of the metabolic pathway, starting from possible release mechanisms and ending with elimination mechanisms. This will allow doctors and researchers to understand the significant importance of cTns metabolism and its impact on the laboratory diagnosis of myocardial infarction.

Biology of Cardiac Troponins: Emphasis on Metabolism

Understanding of the biology of endo- and exogenous molecules, in particular their metabolism, is not only of great theoretical importance, but also of high practical significance, since many molecules serve as drug targets or markers for the laboratory diagnostics of many human diseases. Thus, cardiac troponin (cTns) molecules have long been used as key markers for the confirmation of diagnosis of myocardial infarction (MI), and with the introduction of contemporary (high sensitivity) test methods, many of our concepts related to the biology of these cardiac markers have changed significantly. In current clinical practice, there are opening new promising diagnostic capabilities of cTns, the understanding and justification of which is closely connected with the theoretical principles of the metabolism of these molecules. However, today, the biology and metabolism of cTns have not been properly investigated; in particular, we do not know the precise mechanisms of release of these molecules from the myocardial cells (MCs) of healthy people and the mechanisms of circulation, and the elimination of cTns from the bloodstream. The main purpose of this manuscript is to systematize information about the biology of cTns, with an emphasis on the metabolism of cTns. The format of this paper, starting with the release of cTns in the blood and concluding with the metabolism/filtration of troponins, provides a comprehensive yet logically easy way for the readers to approach our current knowledge in the framework of understanding the basic mechanisms by which cTns are produced and processed. Conclusions. Based on the analysis of the current literature, the important role of biology and all stages of metabolism (release, circulation, removal) of cTns in laboratory diagnostics should be noted. It is necessary to continue studying the biology and metabolism of cTns, because this will improve the differential diagnosis of MI and i a new application of cTns immunoassays in current clinical practice.

Comparison of Troponin I levels versus myocardial dysfunction on prognosis in sepsis

In the context of sepsis, we tested the relationship between echocardiographic findings and Troponin, and their impact on prognosis. In this prospective study, we enrolled 325 septic patients (41% with shock), not mechanically ventilated, between October, 2012 and June, 2019 among those admitted to our High-Dependency Unit. By echocardiography within 24 h from the admission, sepsis-induced myocardial dysfunction (SIMD) was defined as left ventricular (LV) systolic dysfunction (speckle-tracking-based global longitudinal peak systolic strain, GLS, >  - 14%) and/or right ventricular (RV) systolic dysfunction (Tricuspid Annular Plane Systolic Excursion, TAPSE < 16 mm). Troponin I levels were measured upon admission (T0) and after 24 h (T1); it was considered normal if > 0.1 ng/mL. Mortality was assessed at day-7 and day-28 end-points. One-hundred and forty-two patients had normal Troponin level at T0 and T1 (G1), 69 had abnormal levels at T0 or T1 (G2) and 114 showed abnormal Troponin levels at both T0 and T1 (G3). Compared to G1, patients in G3 had worse LV and RV systolic function (GLS  - 11.6 ± 3.4% vs  - 14.0 ± 3.5%, p < 0.001; TAPSE 18 ± 0.5 vs 19 ± 0.5 mm, p = 0.047) and greater day-28 (34% vs 20%, p = 0.015) mortality. In a Cox survival analysis including age, Troponin and SOFA score, mortality was predicted by the presence of SIMD (RR 3.24, 95% CI 1.72-6.11, p < 0.001) with no contribution of abnormal Troponin level. While abnormal Troponin levels were associated with SIMD diagnosed by echocardiography, only the presence of SIMD predicted the short- and medium-term mortality rate, without an independent contribution of increased Troponin levels.

Cardiac troponins: current information on the main analytical characteristics of determination methods and new diagnostic possibilities

The methods used to diagnose cardiovascular diseases are constantly being improved, leading to an expanded perception of the diagnostic value of biomarkers and their new diagnostic possibilities. One striking example are the main biomarkers used to diagnose acute myocardial infarction: cardiac troponins. The first methods for determining cardiac troponins (proposed 30 years ago) were characterized by extremely low sensitivity. Therefore, they could only detect large acute myocardial infarctions. These methods were also characterized by low specificity, expressed as a high probability of cross-reactivity with skeletal troponin isoforms, which generated false-positive results in the presence of skeletal myopathies and skeletal muscle lesions. With the introduction of high-sensitivity cardiac troponins into clinical practice, the possibility of early diagnosis and exclusion of acute myocardial infarction by assessing troponin concentrations in the first few hours (from admission to the first hour, second hour, or third hour) has become more specific. Our knowledge about cardiac troponins has changed over the years and promising new medical uses have emerged. This paper reviews current data on the diagnostic value of cardiac troponins, the main methods used for their determination, and their analytical characteristics from historical and modern insights.

Association between Cardiologist Consultation and Mortality of Stable Patients with Elevated Cardiac Troponin at Admission

Elevated cardiac troponin (cTn) showed associations with mortality even in stable patients, but management has not been established. We aimed to investigate whether consultation to cardiologists could reduce mortality of stable patients with cTn elevation at admission. We identified 1329 patients with elevated cTn level at hospitalization from outpatient clinic to any department other than cardiology or cardiac surgery between April 2010 and December 2018. The patients were divided into two groups according to cardiologist consultation at admission. For primary outcome, mortality during one year was compared in the crude and propensity-score-matched populations. In 1329 patients, 397 (29.9%) were consulted to cardiologists and 932 (70.1%) were not. Mortality during the first year was significantly lower in patients consulted to cardiologists compared with those who were not (9.8% vs. 14.2%; hazard ratio (HR), 0.50; 95% confidence interval (CI), 0.35-0.72; p < 0.001). After propensity-score matching, 324 patients were in the cardiologist consultation group and 560 patients were in the no cardiologist consultation group. One-year mortality was consistently lower in the cardiologist consultation group (10.5% vs. 14.6%; HR, 0.58; 95% CI, 0.39-0.86; p = 0.01). Cardiologist consultation may be associated with lower mortality in stable patients with cTn elevation at admission. Further studies are needed to identify effective management strategies for stable patients with elevated cTn.

The Main Causes and Mechanisms of Increase in Cardiac Troponin Concentrations Other Than Acute Myocardial Infarction (Part 1): Physical Exertion, Inflammatory Heart Disease, Pulmonary Embolism, Renal Failure, Sepsis

The causes and mechanisms of increased cardiac troponin T and I (cTnT and cTnI) concentrations are numerous and are not limited to acute myocardial infarction (AMI) (ischemic necrosis of cardiac myocytes). Any type of reversible or irreversible cardiomyocyte injury can result in elevated serum cTnT and cTnI levels. Researchers and practitioners involved in the diagnosis and treatment of cardiovascular disease, including AMI, should know the key causes and mechanisms of elevated serum cTnT and cTnI levels. This will allow to reduce or completely avoid diagnostic errors and help to choose the most correct tactics for further patient management. The purpose of this article is to discuss the main causes and mechanisms of increase in cardiac troponins concentrations in frequently occurring physiological (physical exertion, psycho-emotional stress) and pathological conditions (inflammatory heart disease, pulmonary embolism, chronic renal failure and sepsis (systemic inflammatory response)) not related to myocardial infarction.

Elevation Mechanisms and Diagnostic Consideration of Cardiac Troponins under Conditions Not Associated with Myocardial Infarction. Part 1

Although cardiac troponins are considered the most specific biomarkers for the diagnosis of acute myocardial infarction (AMI), their diagnostic consideration goes far beyond the detection of this dangerous disease. The mechanisms of cardiac troponin elevation are extremely numerous and not limited to ischemic necrosis of cardiac myocytes. Practitioners should be well aware of the underlying pathological and physiological conditions that can lead to elevated serum levels of cardiac troponins to avoid differential diagnostic errors, which will be greatly increased if clinicians rely on laboratory data alone. This article presents a classification of the main causes of an elevation in cardiac troponins and discusses in detail the mechanisms of such elevation and the diagnostic consideration of cardiac troponins in some conditions not associated with AMI, such as physical exertion, inflammatory heart diseases (myocarditis and endocarditis), pulmonary embolism (PE), renal failure, and systemic inflammation (sepsis).

Neutrophil Elastase Inhibition Ameliorates Endotoxin-induced Myocardial Injury Accompanying Degradation of Cardiac Capillary Glycocalyx

Myocardial injury in sepsis may be caused by a burst of several inflammatory mediators, leading to vascular endothelial injuries. However, the contribution of neutrophil elastase (NE) to myocardial injury in sepsis is still unknown. We aimed to evaluate whether endotoxemia-induced myocardial injury is associated with NE. Lipopolysaccharide (LPS) was injected intraperitoneally at a dose of 20 mg/kg into granulocyte-colony-stimulating-factor knockout mice (G-CSF-KO), which have few neutrophils, and littermate control mice. The survival rate of G-CSF-KO mice 48 hours after LPS injection was significantly greater than that of control mice. The serum level of troponin I in G-CSF-KO mice was significantly lower than that in control mice. In addition, the concentration of inflammatory cytokine interleukin-6 (IL-6) was significantly decreased 6 and 12 hours after LPS administration compared with that in control mice. Ultrastructural analysis revealed that vascular endothelial structures and the endothelial glycocalyx in G-CSF-KO mice were clearly preserved. Next, mice were injected with 0.2 mg/kg sivelestat (an NE inhibitor) after LPS administration. The survival rate was significantly higher and the serum level of troponin I was lower in sivelestat-injected mice than in control mice, respectively. Furthermore, IL-6 levels were significantly decreased 6 and 12 hours after LPS administration compared with those in control mice. Vascular endothelial structures and the endothelial glycocalyx in sivelestat-treated mice were clearly preserved at the ultrastructural level. In conclusion, NE is significantly associated with myocardial injury in endotoxemia. Inhibition of NE may be a useful tool for the management of endotoxemia.

Cardiac Troponins: Contemporary Biological Data and New Methods of Determination

Laboratory diagnosis plays one of the key roles in the diagnosis of many diseases, including cardiovascular diseases (CVD). The methods underlying the in vitro study of many CVD biomarkers, including cardiac troponins (cTnI and cTnT), are imperfect and are continually being improved to enhance their analytical performance, with sensitivity and specificity being the most important. Recently developed improved cTnI and cTnT detection methods, referred to as highly sensitive methods (hs-cTnI, hs-cTnT), have changed many of our ideas about the biology of cardiac troponins and opened up a number of additional diagnostic capabilities for practical healthcare. This article systematizes some relevant data on the biology of cardiac troponins as well as on methods for determining cTnI and cTnT with an analysis of the diagnostic value of their analytical characteristics (limit of blank, limit of detection, 99th percentile, coefficient of variation, and others). Data on extracardiac expression of cTnI and cTnT, mechanisms of formation and potential clinical significance of gender, age, and circadian characteristics of hs-cTnI and hs-cTnT content in serum are discussed. Considerable attention is paid to the discussion of new diagnostic capabilities of hs-cTnI, hs-cTnT, including consideration of promising possibilities for their study in biological fluids that can be obtained by non-invasive methods. Also, some possibilities of using hs-cTnI and hs-cTnT as prognostic laboratory biomarkers in healthy people (for example, to assess the risk of developing CVD) and in patients suffering from a number of pathological conditions that cause damage to cardiomyocytes are examined, and the potential mechanisms underlying the increase in hs-cTnI and hs-cTnT are discussed.

High-sensitivity cardiac troponins: detection and central analytical characteristics

Recently, there have been some important changes in the laboratory diagnosis of patients with acute coronary syndrome, due to the introduction into routine practice of new high- and ultra-sensitive techniques for detection of myocardial damage biomarkers — cardiac troponins. Each method for cardiac troponins’ detection, among the existing wide variety of troponin immunoassays, has different analytical characteristics and allows the detection of different concentrations of troponins in the same patient. With an increasing number of companies developing high-sensitivity troponin immunoassays receiving regulatory approval, there is an urgent need for independent analytical and clinical evaluation of each method. This article discusses high- and ultrasensitive techniques for detection of cardiac troponins. The modern data on biochemical and metabolic characteristics of troponins, obtained using high- and ultra-sensitive techniques, are described: sex, age, circadian features and potential for detecting troponins in other biological fluids. Considerable attention is paid to the analytical characteristics of troponin immunoassays: limit of blank, limit of detection and limit of quantitation, coefficient of variation, as well as the 99th percentile and factors influencing it.

Coronavirus Disease 2019 (COVID-19) and its implications for cardiovascular care: expert document from the German Cardiac Society and the World Heart Federation

Coronavirus diseases 2019 (COVID-19) has become a worldwide pandemic affecting people at high risk and particularly at advanced age, cardiovascular and pulmonary disease. As cardiovascular patients are at high risk but also have dyspnea and fatigue as leading symptoms, prevention, diagnostics and treatment in these patients are important to provide adequate care for those with or without COVID-19 but most importantly when comorbid cardiovascular conditions are present. Severe COVID-19 with acute respiratory distress (ARDS) is challenging as patients with elevated myocardial markers such as troponin are at enhanced high risk for fatal outcomes. As angiotensin-converting enzyme 2 (ACE2) is regarded as the viral receptor for cell entry and as the Coronavirus is downregulating this enzyme, which provides cardiovascular and pulmonary protection, there is ongoing discussions on whether treatment with cardiovascular drugs, which upregulate the viral receptor ACE2 should be modified. As most of the COVID-19 patients have cardiovascular comorbidities like hypertension, diabetes, coronary artery disease and heart failure, which imposes a high risk on these patients, cardiovascular therapy should not be modified or even withdrawn. As cardiac injury is a common feature of COVID-19 associated ARDS and is linked with poor outcomes, swift diagnostic management and specialist care of cardiovascular patients in the area of COVID-19 is of particular importance and deserves special attention.

Distribution of contemporary sensitivity troponin in the emergency department and relationship to 30-day mortality: The CHARIOT-ED substudy

BACKGROUND

Contemporary sensitivity troponin (cs-cTn) concentrations above the upper limit of normal (ULN) are seen in a wide range of clinical conditions and evidence is growing that suggests cs-cTn may be a biomarker of future morbidity and mortality.

OBJECTIVES

Our aim was to test the hypothesis that cs-cTn, measured in the emergency department, may be a biomarker for 30-day mortality, irrespective of the patient's presentation.

METHOD

In all 5,708 consecutive cases, contemporary sensitivity troponin I (cs-cTnI) was measured either as requested by the clinical team or as part of the study, in which case both the clinical team and the patient were unaware of the result. Basic demographics were available from the original study and 30-day mortality was derived from NHS Digital data.

RESULTS

In patients whose cs-cTnI test was requested solely as part of the study, 30-day mortality increased with increasing cs-cTnI concentrations (0% with undetectable concentrations to 14.7% with concentrations above the ULN). Multivariable Cox regression analysis showed that log(10)cs-cTnI concentration was independently associated with 30-day mortality.

CONCLUSION

Increasing cs-cTnI concentrations are associated with higher short-term mortality as well as length of stay. As such, cs-cTnI measurements may provide useful prognostic information.

STAPLAg: a convenient early warning score for use in infected patients in the intensive care unit

Sepsis is a life-threatening disease in the intensive care unit (ICU). The current diagnostic criteria for sequential organ failure assessment (SOFA) scores do not reflect the current understanding of sepsis. We developed a novel and convenient score to aid early prognosis.Retrospective multivariable regression analysis of 185 infected emergency ICU (EICU) patients was conducted to identify independent variables associated with death, to develop the new "STAPLAg" score; STAPLAg was then validated in an internal cohort (n = 106) and an external cohort (n = 78) and its predictive efficacy was compared with that of the initial SOFA score.Age, and initial serum albumin, sodium, PLR, troponin, and lactate tests in the emergency department were independent predictors of death in infected EICU patients, and were used to establish the STAPLAg score (area under the curve [AUC] 0.865). The initial SOFA score on admission was predictive of death (AUC 0.782). Applying the above categories to the derivation cohort yielded mortality risks of 7.7% for grade I, 56.3% for grade II, and 75.0% for grade III. Internal (AUC 0.884) and external (AUC 0.918) cohort validation indicated that the score had good predictive power.The STAPLAg score can be determined early in infected EICU patients, and exhibited better prognostic capacity than the initial SOFA score on admission in both internal and external cohorts. STAPLAg constitutes a new resource for use in the clinical diagnosis of sepsis and can also predict mortality in infected EICU patients. REGISTRATION NUMBER:: ChinCTR-PNC-16010288.

Non-coronarogenic causes of increased cardiac troponins in clinical practice

Cardiospecific isoforms of troponins are the most sensitive and specific biomarkers for the diagnosis of myocardial infarction. However, though elevated troponin levels indicate myocardial damage, they do not determine the cause and mechanism of the damage. With the new highly sensitive methods, very minor damages of the heart muscle can be detected. Myocardial damage can occur in many non-coronarogenic diseases. In this review, we discuss the mechanisms of elevation, the diagnostic value of cardiac troponins in the renal failure, tachyarrhythmias, endocarditis, myocarditis, pericarditis, sepsis, neurogenic pathologies (stroke), pulmonary embolism. In addition, we pay attention to the main reasons for a false-positive increase of the concentration of cardiac troponins: heterophilic antibodies, rheumatoid factor, alkaline phosphatase, cross-reactions with skeletal muscle troponins.

[In-hospital Myocardial Infarction: Scale of the Problem]

All cases of acute myocardial infarction (AMI) can be divided into outpatient-onset AMI and in-hospital-onset AMI depending on the place and circumstances of their development. In this review we consider the problem of in-hospital AMI. Special attention is paid to specific features of its clinical manifestations and the scale of the clinical problem. Possible causes of difficulties in the diagnosis and treatment of this condition are presented in comparison with those in patients with outpatient-onset AMI.

Troponin Testing for Assessing Sepsis-Induced Myocardial Dysfunction in Patients with Septic Shock

(1) Background: Myocardial dysfunction in patients with sepsis is not an uncommon phenomenon, yet reported results are conflicting and there is no objective definition. Measurement of troponin may reflect the state of the heart and may correlate with echocardiographically derived data. This study aimed to evaluate the role of admission and peak troponin-I testing for the identification of sepsis-induced myocardial dysfunction (SIMD) by transthoracic echocardiography (TTE). (2) Methods: This was a retrospective cohort study using a prospective registry of septic shock at an Emergency Department from January 2011 and April 2017. All 1,776 consecutive adult septic shock patients treated with protocol-driven resuscitation bundle therapy and tested troponin-I were enrolled. SIMD was defined as left ventricular (LV) systolic/diastolic dysfunction, right ventricular (RV) diastolic dysfunction, or global/regional wall motion abnormalities (WMA). (3) Results: Of 660 (38.4%) septic shock patients with an elevated hs-TnI (≥0.04 ng/mL) at admission, 397 patients underwent TTE and 258 cases (65%) showed SIMD (LV systolic dysfunction (n = 163, 63.2%), LV diastolic dysfunction (n = 104, 40.3%), RV dysfunction (n = 97, 37.6%), and WMA (n = 186, 72.1%)). In multivariate analysis, peak hs-TnI (odds ratio 1.03, 95% confidence interval 1.01–1.06, p = 0.008) and ST-T wave changes in the electrocardiogram (odds ratio 1.82, 95% confidence interval 1.04–2.39, p = 0.013) were associated with SIMD, in contrast to hs-TnI level at admission. The area under the curve of peak hs-TnI was 0.668. When the peak hs-TnI cutoff value was 0.634 ng/mL, the sensitivity and specificity for SIMD were 58.6% and 59.1%, respectively. 4) Conclusions: About two-thirds of patients with an elevated hs-TnI level have various cardiac dysfunctions in terms of TTE. Rather than the initial level, the peak hs-TnI and ST-T change may be considered as a risk factor of SIMD.

Ready for Prime Time? Biomarkers in Sepsis

Sepsis is a common condition managed in the emergency department. Current diagnosis relies on physiologic criteria and suspicion of a source of infection using history, physical examination, laboratory studies, and imaging studies. The infection triggers a host response with the aim to destroy the pathogen, and this response can be measured. A reliable biomarker for sepsis should assist with earlier diagnosis, improve risk stratification, or improve clinical decision making. Current biomarkers for sepsis include lactate, troponin, and procalcitonin. This article discusses the use of lactate, procalcitonin, troponin, and novel biomarkers for use in sepsis.

Resting heart rate: risk indicator and emerging risk factor in cardiovascular disease

Resting heart rate is central to cardiac output and is influenced by changes occurring in numerous diseases. It predicts longevity and cardiovascular diseases, and current evidence suggests that it is also an important marker of outcome in cardiovascular disease, including heart failure. Beta-blockers improve outcomes in heart failure; however, they have effects outside reducing heart rate. Ivabradine has demonstrated efficacy in reducing rehospitalizations and mortality in heart failure and in improving exercise tolerance and reducing angina attacks in patients with coronary artery disease, whereas selective heart rate reduction may also prove to be beneficial in therapeutic areas outside those in which ivabradine has already demonstrated clinical efficacy. This review provides an update on the associations between heart rate and cardiovascular outcomes in various conditions, the experimental effects of heart rate reduction with ivabradine, and the potential new indications in cardiovascular disease.