High-sensitivity cardiac troponin I and risk of cardiovascular disease in an Australianpopulation-based cohort

Association between high-sensitivity cardiac troponin I and fall-related hospitalisation in women aged over 70 years

OBJECTIVE

To examine the association between high-sensitivity cardiac troponin I (hs-cTnI), a biomarker of myocardial injury, muscle function decline and 14.5-year fall-related hospitalisation risk in women aged over 70 years.

METHODS

1179 ambulatory community-dwelling women aged over 70 years with subclinical levels of hs-cTnI (ie, <15.6 ng/L), who were followed up for 14.5 years, were included. Samples for hs-cTnI were obtained in 1998. Fall-related hospitalisations were retrieved from linked health records. Muscle function measures, including handgrip strength and the Timed-Up-and-Go (TUG) test, were assessed in 1998 and 2003.

RESULTS

Mean±SD age was 75.2±2.7 years. Over 14.5 years of follow-up, 40.4% (476 of 1179) experienced fall-related hospitalisation. Participants were categorised into four approximate hs-cTnI quartiles: quartile 1 (<3.6 ng/L), quartile 2 (3.6-4.4 ng/L), quartile 3 (4.5-5.8 ng/L) and quartile 4 (≥5.9 ng/L). Compared with those in Q1, women in Q4 were likely to experience fall-related hospitalisation (36.0% vs 42.8%). In a multivariable-adjusted model that accounted for CVD and fall risk factors, compared with women in Q1, those in Q4 had a 46% higher risk of fall-related hospitalisation (HR 1.46, 95% CI 1.08 to 1.98). Additionally, women in Q4 had slower TUG performance compared with those in Q1 (10.3 s vs 9.5 s, p=0.032).

CONCLUSION

Elevated level of hs-cTnI was associated with slower TUG performance and increased fall-related hospitalisation risk. This indicates subclinical level of hs-cTnI can identify clinically relevant falls, emphasising the need to consider cardiac health during fall assessment in women aged over 70 years.

TRIAL REGISTRATION NUMBER

ACTRN12617000640303.

Conventional Biomarkers for Predicting Clinical Outcomes in Patients with Heart Disease

Atherosclerosis is the main cause of cardiovascular disease worldwide. The progression of coronary atherosclerosis leads to coronary artery disease, with impaired blood flow to the myocardium and subsequent development of myocardial ischemia. Acute coronary syndromes and post-myocardial infarction heart failure are two of the most common complications of coronary artery disease and are associated with worse outcomes. In order to improve the management of patients with coronary artery disease and avoid major cardiovascular events, several risk assessment tools have been developed. Blood and imaging biomarkers, as well as clinical risk scores, are now available and validated for clinical practice, but research continues. The purpose of the current paper is to provide a review of recent findings regarding the use of humoral biomarkers for risk assessment in patients with heart disease.

Towards Multiplexed and Multimodal Biosensor Platforms in Real-Time Monitoring of Metabolic Disorders

Metabolic syndrome (MS) is a cluster of conditions that increases the probability of heart disease, stroke, and diabetes, and is very common worldwide. While the exact cause of MS has yet to be understood, there is evidence indicating the relationship between MS and the dysregulation of the immune system. The resultant biomarkers that are expressed in the process are gaining relevance in the early detection of related MS. However, sensing only a single analyte has its limitations because one analyte can be involved with various conditions. Thus, for MS, which generally results from the co-existence of multiple complications, a multi-analyte sensing platform is necessary for precise diagnosis. In this review, we summarize various types of biomarkers related to MS and the non-invasively accessible biofluids that are available for sensing. Then two types of widely used sensing platform, the electrochemical and optical, are discussed in terms of multimodal biosensing, figure-of-merit (FOM), sensitivity, and specificity for early diagnosis of MS. This provides a thorough insight into the current status of the available platforms and how the electrochemical and optical modalities can complement each other for a more reliable sensing platform for MS.

High-sensitivity troponins for outcome prediction in the general population: a systematic review and meta-analysis

BACKGROUND

High-sensitivity (hs) assays allow to measure cardiac troponin T and I (cTnT/I) even in healthy individuals. The higher hs-cTn values, the higher the ongoing cardiomyocyte damage, and then reasonably the risk of developing symptomatic cardiac disease.

METHODS

We retrieved all studies evaluating the prognostic value of hs-cTnT or I in the general population. We calculated pooled hazard ratio (HR) values for all-cause and cardiovascular death, cardiovascular events and heart failure (HF) hospitalization.

RESULTS

We included 24 studies for a total of 203,202 subjects; 11 studies assessed hs-cTnT and 14 hs-cTnI. One standard deviation (SD) increase in baseline hs-cTn was associated with a 23% higher risk of all-cause death (HR 1.226, 95% CI 1.083-1.388, p<0.001, I²=88.5%); all these studies measured hs-cTnI. In an exploratory analysis on 3 studies with 25,760 subjects, hs-cTn predicted cardiovascular death (HR 1.822, 95% CI 1.241-2.674, p=0.002, I²=87.2%). After synthesizing 9 studies with 58,565 subjects, hs-cTn predicted cardiovascular events (HR 1.328, 95% CI 1.167-1.513, p<0.001, I²=93.8%). Both hs-cTnT (HR 1.627, 95% CI 1.145-2.311, p<0.001) and hs-cTnI (HR 1.260, 95% CI 1.115-1.423, p<0.001; p for interaction <0.001). Furthermore, in 10 studies with 61,467 subjects, hs-cTn predicted HF hospitalization (HR 1.493, 95% CI 1.368-1.630, p<0.001, I²=76.6%). Both hs-cTnT (HR 1.566, 95% CI 1.303-1.883, p<0.001) and hs-cTnI (HR 1.467, 95% CI 1.321-1.628, p<0.001) were associated with HF hospitalization (p for interaction <0.001).

CONCLUSIONS

hs-cTn values hold strong prognostic value in subjects from the general population, predicting the risk of all-cause and cardiovascular mortality, cardiovascular events, and HF hospitalization.

Effect of positive airway pressure on cardiac troponins in patients with sleep-disordered breathing: A meta-analysis

Background

Cardiac troponins are highly sensitive and specific biomarkers for cardiac injury. Previous studies evaluating the effect of positive airway pressure (PAP) on cardiac troponins in patients with sleep‐disordered breathing (SDB) have yielded conflicting results. The meta‐analysis was performed to examine the effect of PAP on cardiac troponins in SDB patients.

Methods

PubMed, Web of Science, and EMBASE before September 2021 on original English language studies were searched. The data on cardiac troponins in both baseline and post‐PAP treatment were extracted from all studies. The data on the change of cardiac troponins in both PAP and control group were extracted from randomized controlled trials. Standardized mean difference (SMD) was used to synthesize quantitative results.

Results

A total of 11 studies were included. PAP treatment was not associated with a significant change in cardiac troponin T between the baseline and post‐PAP treatment (SMD = −0.163, 95% confidence interval [CI] = −0.652 to 0.326, z = 0.65, p = .514). The pooled estimate of SMD of cardiac troponin I between the pre‐ and post‐PAP treatment was 0.287, and the 95% CI was −0.586 to 1.160 (z = 0.64, p = .519). The pooled SMD of change of cardiac troponin T between the PAP group and control group was −0.473 (95% CI = −1.198 to 0.252, z = 1.28, p = .201).

Conclusions

This meta‐analysis revealed that PAP treatment was not associated with any change of cardiac troponin in SDB patients.

Genetically Predicted Cardiac Troponin I Concentrations and Risk of Stroke and Atrial Fibrillation

OBJECTIVES

Observational studies have shown that elevated circulating cardiac troponin I (cTnI) concentrations were linked to higher risk of stroke and atrial fibrillation, but the causality remains unclear. Therefore, we used mendelian randomization to assess the potential causal effects of cTnI concentrations on the risk of stroke, its subtypes and atrial fibrillation.

MATERIALS AND METHODS

The instrumental variables for circulating cTnI concentrations were selected from a genome-wide association study meta-analysis of 48,115 European individuals. We examined the associations of circulating cTnI concentrations with stroke, ischemic stroke, ischemic stroke subtypes (cardioembolic, large artery, small vessel stroke), intracerebral hemorrhage and atrial fibrillation.

RESULTS

Genetically predicted elevated circulating cTnI concentrations were associated with higher risk of cardioembolic stroke (odds ratio [OR], 1.80; 95% confidence interval [CI], 1.20-2.68; P = 0.004), but not associated with large artery stroke, small vessel stroke, total stroke, ischemic stroke and intracerebral hemorrhage. Additionally, we also found that elevated cTnI concentrations were causally linked to higher risk of atrial fibrillation (OR, 1.30; 95% CI, 1.10-1.53; P = 0.003).

CONCLUSIONS

This study provides evidence that genetically predicted circulating cTnI concentrations are causally linked to higher risk of cardioembolic stroke and atrial fibrillation.

Use of high-sensitivity cardiac troponins in the emergency department for the early rule-in and rule-out of acute myocardial infarction without persistent ST-segment elevation (NSTEMI) in Italy

Serial measurements of cardiac troponin are recommended by international guidelines to diagnose myocardial infarction (MI) since 2000. However, some relevant differences exist between the three different international guidelines published between 2020 and 2021 for the management of patients with chest pain and no ST-segment elevation. In particular, there is no agreement on the cut-offs or absolute change values to diagnose non-ST-segment elevation MI (NSTEMI). Other controversial issues concern the diagnostic accuracy and cost-effectiveness of cut-off values for the most rapid algorithms (0 h/1 h or 0 h/2 h) to rule-in and rule-out NSTEMI. Finally, another important point is the possible differences between demographic and clinical characteristics of patients enrolled in multicenter trials compared to those routinely admitted to the Emergency Department in Italy. The Study Group of Cardiac Biomarkers, supported by the Italian Scientific Societies Società Italiana di Biochimica Clinica, Italian Society of the European Ligand Assay Society, and Società Italiana di Patolgia Clinica e Medicina di Laboratorio decided to revise the document previously published in 2013 about the management of patients with suspected NSTEMI, and to provide some suggestions for the use of these biomarkers in clinical practice, with a particular focus on the Italian setting.

Sortilin and Homocysteine as Potential Biomarkers for Coronary Artery Diseases

Purpose

The aim of this study was to assess the relationship of coronary artery disease (CAD) with levels of homocysteine and sortilin in Egyptian patients.

Background

CAD is a primary contributor to cardiac disease and a prominent cause of death globally.

Patients and Methods

We enrolled 45 patients with CAD evaluated by coronary CT angiography and 42 control subjects without CAD. Plasma-homocysteine and -sortilin levels were measured with a commercial ELISA kit.

Results

Elevated levels of homocysteine and sortilin were observed in the CAD patients compared to controls (13.75±1.40 vs 7.73±2.06 μmol/L, P=0 and 160.91±32.17 vs 143.02±32.30 ng/dL, P=0.02, respectively). Significantly higher total cholesterol, low density–lipoprotein cholesterol and triglycerides (P<0.05) and lower high density–lipoprotein cholesterol (P<0.05) were seen among patients with CAD than the control group. Sortilin levels were positively associated with homocysteine levels (r=0.32, P=0.006), total cholesterol (r=0.61, P=0), low density–lipoprotein cholesterol (r=0.37, P=0.001), triglycerides (r=0.91, P=0), troponin I (r=0.82, P=0), Gensini score (r=0.93, P=0) and high-sensitivity CRP (r=0.87, P=0) in all subjects. Homocysteine has a significantly negative association with high density–lipoprotein cholesterol (r=−0.42, P=0).

Conclusion

Elevated homocysteine and sortilin levels are crucial risk factors of CAD in Egyptian patients.

Diagnostic algorithms for non-ST-segment elevation myocardial infarction: open issues

The use of serial measurement of cardiac troponin (cTn) is recommended by international guidelines for the diagnosis of myocardial infarction (MI) since 2000. This article focuses on factors influencing temporal changes in high-sensitive cTn (hs)-cTn and the impact of these factors on the diagnosis of non-ST-segment elevation MI (NSTEMI). The recommendations proposed by three different international guidelines published in 2020-2021 for the management of acute coronary syndromes (ACS) in patients presenting without persistent ST-segment elevation (NSTE) show some discrepancies. In particular, there is no agreement among these guidelines about cut-off or absolute change values to be used for the rule-in, especially regarding the use of sex-specific cut-off values. Furthermore, there are no sufficient evidences on the diagnostic accuracy and cost effectiveness related to cut-off values suggested for algorithms to be used by some hs-cTnI methods.

Atrial heat shock protein levels are associated with early postoperative and persistence of atrial fibrillation

BACKGROUND

Early detection and staging of atrial fibrillation (AF) is of importance for clinical management. Serum (bio)markers, such as heat shock proteins (HSP), may enable AF staging and identify patients at risk for AF recurrence and postoperative AF (PoAF).

OBJECTIVE

This study evaluates the relation between serum and atrial tissue HSP levels, stages of AF, AF recurrence after treatment, and PoAF from patients undergoing cardiothoracic surgery.

METHODS

Patients without (control) and with paroxysmal, persistent (PerAF), or longstanding persistent (LSPerAF) AF were included. HSPB1, HSPA1, HSPB7, and HSPD1 levels were measured in serum obtained prior to and post intervention. HSPB1, HSPA1, HSPA5, HSPD1, HSPB5, and pHSF1 levels were measured in left and/or right atrial appendages (respectively, LAA and RAA).

RESULTS

In RAA, HSPA5 levels were significantly lower in LSPerAF and HSPD1 levels significantly higher in PerAF patients compared to controls. In RAA of controls who developed PoAF, HSPA1 and HSPA5 levels were significantly higher compared to those without PoAF. Also, HSPB1 RAA levels were lower and HSPA5 LAA levels higher in patients undergoing arrhythmia surgery who developed AF recurrence within 1 week after surgery compared to patients who did not.

CONCLUSION

HSPA5 RAA and HSPD1 RAA and LAA levels are altered in persistent stages of AF. RAA HSPA1 and HSPA5 levels associate with development of PoAF. Additionally, HSPB1 RAA and HSPA5 LAA levels can predict AF recurrence in patients who underwent arrhythmia surgery. Nevertheless, HSP levels in serum cannot discriminate AF stages from controls, nor predict PoAF or AF recurrence after treatment.

Cardiac troponins: are there any differences between T and I?

The most recent international guidelines recommend the measurement of cardiac troponin I (cTnI) and cardiac troponin T (cTnT) using high-sensitivity methods (hs-cTn) for the detection of myocardial injury and the differential diagnosis of acute coronary syndromes. Myocardial injury is a prerequisite for the diagnosis of acute myocardial infarction, but also a distinct entity. The 2018 Fourth Universal Definition of Myocardial Infarction states that myocardial injury is detected when at least one value above the 99th percentile upper reference limit is measured in a patient with high-sensitivity methods for cTnI or cTnT. Not infrequently, increased hs-cTnT levels are reported in patients with congenital or chronic neuromuscular diseases, while the hs-cTnI values are often in the normal range. Furthermore, some discrepancies between the results of laboratory tests for the two troponins are occasionally found in individuals apparently free of cardiac diseases, and also in patients with cardiac diseases. In this review article, authors discuss the biochemical, pathophysiological and analytical mechanisms which may cause discrepancies between hs-cTnI and hs-cTnT test results.

Clinical relevance of biological variation of cardiac troponins

The high-sensitivity immunoassays for cardiac troponin I (hs-cTnI) and cardiac troponin T (hs-cTnT) are recommended by all the most recent international guidelines as gold standard laboratory methods for the detection of myocardial injury and diagnosis of acute myocardial infarction (AMI). In this review article, the Authors aimed at discussing the relevant biochemical, physiological, and clinical issues related to biological variability of cTnI and cTnT. Cardiac troponins, measured with hs-cTn methods, show a better clinical profile than the other cardio-specific biomarkers (such as the natriuretic peptides, BNP and NT-proBNP). In particular, the hs-cTn methods are characterized by a low intra-individual index of variation (<0.6) and reduced analytical imprecision (about 5% CV) at the clinical cut-off value (i.e., the 99th percentile URL value). Moreover, recent studies have reported that differences between two hs-cTn measured values (RCV) >30% can be considered statistically significant. These favourable biological characteristics and analytical performance of hs-cTn methods significantly improved the accuracy in the diagnostic process of acute coronary syndromes (ACS) in patients admitted to emergence department. In addition, several studies have demonstrated the clinical usefulness of cardiovascular risk evaluation with hs-cTn methods in some groups of patients with clinical conditions at high cardiovascular risk (such as systemic hypertension, severe obesity, diabetes mellitus, renal insufficiency, and chronic obstructive pulmonary disease). However, screening programs in the general population with hs-cTn methods for cardiovascular risk stratification require further investigation to define the optimal target populations, timing of measurement, and preventive interventions.

High-sensitivity methods for cardiac troponins: The mission is not over yet

The measurement of cardiac troponin (cTn) is recommended by all guidelines as the gold standard for the differential diagnosis of Acute Coronary Syndromes. The aim of this review is to discuss in details some key issues regarding both analytical and clinical characteristics of the high-sensitivity methods for cTn (hs-cTn), which are still considered controversial or unresolved. In particular, the major clinical concern regarding hs-cTn methods is the difficulty to differentiate the pathophysiological mechanism responsible for biomarker release from cardiomyocytes after reversible or irreversible injury, respectively. Indeed, recent experimental and clinical studies have demonstrated that different circulating forms of cTnI and cTnT can be respectively measured in plasma samples of patients with reversible or irreversible myocardial injury. Accordingly, a new generation of hs-Tn methods should be set up, based on immunometric immunoassays or chromatographic techniques, specific for circulating peptide forms more characteristics for reversible or irreversible myocardial injury. It is conceivable that this new generation of hs-cTn methods will complete the mission regarding the laboratory tests for specific cardiac biomarkers, started more than 20 years ago, which has already revolutionized the diagnosis, prognosis and management of patients with cardiac diseases.

Is the true clinical value of high-sensitivity troponins as a biomarker of risk? The concept that detection of high-sensitivity troponin 'never means nothing'

INTRODUCTION

High-sensitivity troponin (hs-cTn) assays are central to the diagnosis of myocardial infarction (MI). Their increased sensitivity has facilitated rapid pathways for the exclusion of MI. However, hs-cTn is now more readily detectable in patients without symptoms typical of MI, in whom a degree of myocardial injury is assumed. Recently, the practice of using the 99^th centile of hs-cTn as a working 'upper reference limit' has been challenged. There is increasing evidence that hs-cTn may provide useful prognostic information, regardless of any suspicion of MI, and as such these assays may have potential as a general biomarker for mortality. This raises the concept that detection of hs-cTn 'never means nothing.'

AREAS COVERED

In this review, we will evaluate the evidence for the use of hs-cTn assays outside their common clinical indication to rule out or diagnose acute MI.

EXPERT OPINION

The data presented suggest that hs-cTn testing may in the future have a generalized role as a biomarker of mortality risk and may be used less as a test for ruling in acute MI, but will remain a frontline test to exclude that diagnosis in ED. Further, the data suggest that the detection of hs-cTn 'never means nothing.'

Cardiotoxic effects and myocardial injury: the search for a more precise definition of drug cardiotoxicity

Drug-induced cardiotoxicity is a major clinical problem; cardiotoxic drugs may induce both cardiac dysfunction and myocardial injury. Several recent studies reported that cardiac troponins measured with high-sensitivity methods (hs-cTn) can enable the early detection of myocardial injury related to chemotherapy or abuse of drugs that are potentially cardiotoxic. Several authors have some concerns about the standard definition of cardiotoxicity, in particular, regarding the early evaluation of chemotherapy cardiotoxicity in cancer patients. Several recent studies using the hs-cTn assay indicate that myocardial injury may precede by some months or years the diagnosis of heart failure (HF) based on the evaluation of left ventricular ejection fraction (LVEF). Accordingly, hs-cTn assay should considered to be a reliable laboratory test for the early detection of asymptomatic or subclinical cardiotoxic damage in patients undergoing cancer chemotherapy. In accordance with the Fourth Universal Definition of Myocardial Infarction and also taking into account the recent experimental and clinical evidences, the definition of drug-cardiotoxicity should be updated considering the early evaluation of myocardial injury by means of hs-cTn assay. It is conceivable that the combined use of hs-cTn assay and cardiac imaging techniques for the evaluation of cardiotoxicity will significantly increase both diagnostic sensitivity and specificity, and also better prevent chemotherapy-related left ventricular (LV) dysfunction and other adverse cardiac events. However, large randomized clinical trials are needed to evaluate the cost/benefit ratio of standardized protocols for the early detection of cardiotoxicity using hs-cTn assay in patients receiving chemotherapy for malignant diseases.

Early evaluation of myocardial injury by means of high-sensitivity methods for cardiac troponins after strenuous and prolonged exercise

All the latest international guidelines recommend that cardiac troponin (cTn) I and T should be considered the preferred biomarkers for diagnosis of acute myocardial infarction. However, only in the last 5 years, a progressive improvement in analytical performance of immunometric assays has allowed the measurement of circulating levels of cTnI and cTnT in the large part of apparently healthy adult subjects. The routine use of these high-sensitivity methods for cardiac troponin (hs-cTn) assay has in a short time demonstrated that cardiac troponin concentrations frequently increase after strenuous prolonged exercise in healthy athletes. This acute response of hs-cTn assay following exercise was at first considered to be physiological and without long-term adverse consequences. More recent studies have suggested that exercise-induced increases in hs-cTn values may not be always a physiological response to exercise, but, conversely, it should sometimes be considered as an early cardiovascular risk marker. The aim of this review is to provide an overview of acute and chronic effects of strenuous physical exercise on hs-cTn circulating levels and also to discuss the potential pathophysiological and clinical implications of biomarker responses.

Evidence on clinical relevance of cardiovascular risk evaluation in the general population using cardio-specific biomarkers

In recent years, the formulation of some immunoassays with high-sensitivity analytical performance allowed the accurate measurement of cardiac troponin I (cTnI) and T (cTnT) levels in reference subjects. Several studies have demonstrated the association between the risk of major cardiovascular events and cardiac troponin concentrations even for biomarker values within the reference intervals. High-sensitivity cTnI and cTnT methods (hs-cTn) enable to monitor myocardial renewal and remodelling, and to promptly identify patients at highest risk ofheart failure. An early and effective treatment of individuals at higher cardiovascular risk may revert the initial myocardial remodelling and slow down heart failure progression. Specific clinical trials should be carried out to demonstrate the efficacy and efficiency of the general population screening by means of cost-benefit analysis, in order to better identify individuals at higher risk for heart failure (HF) progression with hs-cTn methods.

High-Sensitivity Cardiac Troponin I Improves Cardiovascular Risk Prediction in Older Men: HIMS (The Health in Men Study)

Background

The Framingham Risk Score estimates the 10‐year risk of cardiovascular events. However, it performs poorly in older adults. We evaluated the incremental benefit of adding high‐sensitivity cardiac troponin I (hs‐cTnI) to the Framingham Risk Score.

Methods and Results

The HIMS (Health in Men Study) is a cohort study of community‐dwelling men aged 70 to 89 years in Western Australia. Participants were identified from the electoral roll, with a subset undergoing plasma analysis. Hs‐cTnI (Abbott Architect i2000SR) was measured in 1151 men without prior cardiovascular disease. The Western Australia Data Linkage System was used to identify incident cardiovascular events. After 10 years of follow‐up, 252 men (22%) had a cardiovascular event (CVE+) and 899 did not (CVE–). The Framingham Risk Score placed 148 (59%) CVE+ and 415 (46%) CVE– in the high‐risk category. In CVE– men, adding hs‐cTnI affected the risk categories of 244 (27.2%) men, with 64.8% appropriately reclassified to a lower and 35.2% to a higher category, which decreased the number of high‐risk men in the CVE– to 39%. In CVE+ men, adding hs‐cTnI affected the risk categories of 61 (24.2%), with 50.8% appropriately reclassified to a higher and 49.2% to a lower category and 82.5% remaining above the 15% risk treatment threshold. The net reclassification index was 0.305 (P<0.001). Adding hs‐cTnI increased the C‐statistic modestly from 0.588 (95% CI, 0.552–0.624) to 0.624 (95% CI, 0.589–0.659) and improved model fit (likelihood ratio test, P<0.001).

Conclusions

Adding hs‐cTnI to the Framingham Risk Score provided incremental prognostic benefit in older men, especially aiding reclassification of individuals into a lower risk category.

High-sensitivity cardiac troponin I and T methods for the early detection of myocardial injury in patients on chemotherapy

Important advances achieved in pharmacological cancer treatment have led progressively to a reduction in mortality from many forms of cancer, and increasing numbers of previously incurable patients can now hope to become cancer-free. Yet, to achieve these improved outcomes a high price has been paid in terms of untoward side effects associated with treatment, cardio-toxicity in particular. Several recent studies have reported that cardiac troponin assay using high-sensitivity methods (hs-cTn) can enable the early detection of myocardial injury related to chemotherapy or abuse of drugs that are potentially cardiotoxic. Several authors have recently suggested that changes in hs-cTn values enable the early diagnosis of cardiac injury from chemotherapy, thus potentially benefitting cancer patients with increased troponin values by initiating early cardioprotective therapy. However, large randomised clinical trials are needed in order to evaluate the cost/benefit ratio of standardised protocols for the early detection of cardiotoxicity using the hs-cTn assay in patients treated with chemotherapy.

Carotid Intima-Media Thickness is a Predictor of Subclinical Myocardial Damage in Men with Type 2 Diabetes Mellitus

BACKGROUND

Type 2 diabetes mellitus (T2DM) promotes the development of atherosclerosis and is a major risk factor for cardiovascular disease. High-sensitivity cardiac troponin I (hs-cTnI) assays fundamentally improved the diagnosis of myocardial injury and even enable the prediction of future cardiovascular events in the general population. However, data about the association of hs-cTnI with cardiovascular risk factors and carotid intima media thickness (cIMT) as a marker of atherosclerosis are limited, especially in patients with T2DM.

METHODS

In this cross-sectional study we analyzed clinical and laboratory parameters of 234 patients (43% women) with T2DM and a median age of 65 years (interquartile range: 57-71). The median duration of diabetes mellitus was 10 years (6-17). Anthropometric data, blood pressure, glycemic parameters and lipid profiles were determined. Hs-cTnI plasma concentrations were measured on an ADVIA Centaur XPT immunoassay analyzer and cIMT was evaluated by high-resolution ultrasound.

RESULTS

Hs-cTnI plasma concentrations were below the gender-specific 99^th  percentile in 93% of T2DM patients with a median concentration of 4.0 ng/l (interquartile range: 2.0-10.0). Hs-cTnI was significantly associated with gender, renal function and C-reactive protein in the entire study cohort. Gender-specific analyses revealed cIMT and renal function to be significantly associated with hs-cTnI in men. Contrary, only age was significantly associated with hs-cTnI in women.

CONCLUSION

In a real-world clinical setting in patients with T2DM, cIMT is a predictor of subclinical myocardial damage in men, but not in women.

Association Between High-Sensitivity Cardiac Troponin and Risk of Stroke in 96 702 Individuals: A Meta-Analysis

Background and Purpose- Our study aim was to estimate risk of incident stroke based on levels of hs-cTn (high-sensitivity cardiac troponin), a specific biomarker indicating myocardial injury, in the general population, patients with atrial fibrillation, and patients with previous stroke. Methods- Embase, PubMed, and Web of Science were searched until March 14, 2019 to identify relevant articles. Randomized controlled trials and cohort studies assessing the risk of incident stroke based on hs-cTn were eligible. Pooled adjusted hazard ratios including 95% CI were calculated using a random-effects model due to study heterogeneity per population, coding of hs-cTn (categorical/continuous data), per hs-cTn subunit (T or I), for low risk of bias, and for all-cause and ischemic stroke separately. Results- We included 17 articles with 96 702 participants. In studies conducted in the general population (n=12; 77 780 participants), the pooled adjusted hazard ratio for incident stroke was 1.25 (CI, 1.10-1.40) for high versus low hs-cTn (as defined by included studies) during an average follow-up of 1 to 20 years (median 10). When categorical data were used, this was increased to 1.58 (CI, 1.26-1.90). The results were robust when accounting for stroke classification (all-cause stroke/ischemic stroke), hs-cTn subunit, risk of bias, and coding of hs-cTn. In patients with atrial fibrillation (4 studies; 18 725 participants), the pooled adjusted hazard ratio for incident stroke was 1.95 (CI, 1.29-2.62) for high versus low hs-cTn. Due to lack of data (one study, 197 participants), no meta-analysis could be performed in patients with previous stroke. Conclusions- This meta-analysis suggests that hs-cTn can be regarded as a risk marker for incident stroke, with different effect size in different subgroups. More research about the association between hs-cTn and incident stroke in high-risk populations is needed, especially in patients with history of ischemic stroke.

High-sensitivity troponin I and B-type natriuretic peptide biomarkers for prediction of cardiovascular events in patients with coronary artery disease with and without diabetes mellitus

Background

High-sensitivity troponin I (hs-Tnl) and B-type natriuretic peptide (BNP) are promising prognostic markers for coronary artery disease (CAD). This prospective cohort study investigated whether a combination of these cardiac biomarkers with conventional risk factors would add incremental value for the prediction of secondary major adverse cardiovascular events (MACEs) in patients with CAD, with and without type 2 diabetes mellitus (T2DM).

Methods

Baseline plasma level of hs-Tnl and BNP was measured in 2275 Chinese patients with stable CAD. Patients were monitored for new-onset of MACE over a median of 51 months. Cox proportional hazard model and area under the receiver operating characteristic curve (AUC) were used to assess the association of cardiac biomarkers with MACE and their predictive values in relationship with or without T2DM.

Results

During the follow up period 402 (18%) patients experienced a new-onset MACE with hs-Tnl and BNP level significantly higher than in those without MACE. In multivariable analyses, patients with elevated hs-Tnl (hazard ratio, 1.75 [95% CI 1.41–2.17]; P < 0.001) and BNP (hazard ratio, 1.42 [95% CI 1.15–1.75]; P = 0.001) were significantly associated with an increased risk of MACE after adjustment for variables of a risk factor model of age, sex, T2DM and hypertension. The risk factor model had an AUC of 0.64 for MACE prediction. The AUC significantly increased to 0.68 by the addition of hs-Tnl to the risk factor model. Subgroup analyses showed that hs-Tnl and BNP remained significant predictors of MACE in both patients with and without T2DM in multivariable models with higher risk of MACE evident in those without T2DM. Among patients without T2DM, addition of each biomarker yielded greater predictive accuracy than in T2DM patients, with AUC further increased to 0.75 when a combination of hs-Tnl and BNP was added to the risk factor model (age, sex and hypertension).

Conclusions

Elevated hs-Tnl and BNP level are independent predictors of new-onset MACE in CAD patients, irrespective of diabetes status. Among CAD patients without T2DM, a combination of cardiac biomarkers hs-Tnl and BNP yield the greatest predictive value beyond conventional risk factors.

Short-term effects of ambient air pollution and outdoor temperature on biomarkers of myocardial damage, inflammation and oxidative stress in healthy adults

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The mechanisms whereby ambient air pollution and temperature changes promote cardiac events remain incompletely described. Seventy-three nonsmoking healthy adults (mean age 23.3, SD 5.4 years) were followed with up to four repeated visits across 15 months in Beijing in 2014–2016. Biomarkers relevant to myocardial damage (high-sensitivity cardiac troponin I [hs-cTnI]), inflammation (growth differentiation factor-15 [GDF-15]), and oxidative stress (8-hydroxy-2′-deoxyguanosine [8-OHdG]) were measured at each visit, while ambient air pollution and temperature were monitored throughout the study. Linear mixed-effects models coupled with distributed lag nonlinear models were used to assess the impacts of each exposure measure on study outcomes. During follow-up, average daily concentrations of fine particulate matter and outdoor temperature were 62.9 µg/m³ (8.1–331.0 µg/m³) and 10.1 °C (−6.5°C to 29.5°C). Serum hs-cTnI levels were detectable in 18.2% of blood samples, with 27.4% of individuals having ≥1 detectable values. Higher levels of ambient particulates and gaseous pollutants (per interquartile range) up to 14 days before clinical visits were associated with significant alterations in hs-cTnI levels of 22.9% (95% CI, 6.4, 39.4) to 154.7% (95% CI, 94.4, 215.1). These changes were accompanied by elevations of circulating GDF-15 and urinary 8-OHdG levels. Both low (5th percentile, −2.5 °C) and high (95th percentile, 24.8°C) outdoor temperatures, with breakpoint at ~13.0°C as the reference level, were also associated with elevations of hs-cTnI levels. Short-term exposure to ambient air pollution and temperature was associated with cardiac troponin, a biomarker of myocardial damage, along with increased inflammation and oxidative stress responses. These findings extend our understanding of the biological mechanisms linking pervasive environmental exposure to adverse cardiac events.

Prognostication of clinical outcomes in diabetes mellitus: Emerging role of cardiac biomarkers

Type 2 diabetes mellitus (T2DM) remains substantial health problem and one of the most prevalent metabolic diseases worldwide. The impact of T2DM on CV mortality and morbidity is embedded through a nature evolution of the disease and is modulated by numerous risk factors, such as hypertension, obesity, dyslipidemia. There is large body of evidence regarding use of the cardiac biomarkers to risk stratification at higher CV risk individuals who belongs to general population and cohort with established CV disease. Although T2DM patients have higher incidence of cardiac and vascular complications than the general population, whether cardiac biomarkers would be effective to risk stratification of the T2DM is not fully understood. The aim of the review is to summarize our knowledge regarding clinical implementation of cardiac biomarkers in risk assessment for T2DM patients. The role of natriuretic peptides, soluble ST2, galectin-3, growth differentiation factor-15, and cardiac troponins are widely discussed.

Non-coronary predictors of elevated high-sensitive cardiac troponin T (hs-cTnT) levels in an unselected emergency patient cohort

BACKGROUND

Aim of this study was to evaluate the predictors of hs-cTnT in a non-ACS patient cohort admitted to the emergency department.

HYPOTHESIS

Atrial fibrillation and hypertension may not always be sufficient for elevation for hs-cTnT.

METHODS

We performed a retrospective, single center study encompassing in total 1003 patients. Individuals were retrospectively divided in ACS- and non-ACS patients by two independent investigators reviewing the medical records. In order to identify predictors of hs-cTnT elevation hazard ratios were calculated for age, gender, vital signs, cardiovascular risk factors, LVEF, serum levels of CRP, hemoglobin, and creatinine. Elevation of hs-cTnT was defined by exceeding 14 ng/L (upper reference limit [URL]).

RESULTS

About 987 patients were included while 25 patients were excluded because of missing data. 307 patients (31.4%) met the current guideline requirements of diagnosing an ACS, whereas 671 patients (68.6%) were hospitalized with excluded ACS. In the multivariate analysis age, anemia, CRP, creatinine, and reduced systolic left ventricular ejection fraction were independent predictors of elevated troponin T levels in the non-ACS group. However, hypertensive systolic blood pressure, atrial fibrillation and tachycardia were not predictive for Troponin T elevation in non-ACS patients in this multivariate analysis.

CONCLUSIONS

In an unselected, non-ACS patient cohort age, chronic renal failure, inflammatory state, and reduced left ventricular systolic function were associated with hs-cTnT levels above the upper reference limit. Rather, often supposed predictors as atrial fibrillation, hypertension, and tachycardia cannot sufficiently explain increased hs-cTnT in our study. Hence, further studies are needed to assess whether isolated hypertension, tachycardia, or atrial fibrillation sufficiently explain elevated hs-cTnT.

Detectable High-Sensitivity Cardiac Troponin within the Population Reference Interval Conveys High 5-Year Cardiovascular Risk: An Observational Study

BACKGROUND

Increased cardiac troponin I or T detected by high-sensitivity assays (hs-cTnI or hs-cTnT) confers an increased risk of adverse prognosis. We determined whether patients presenting with putatively normal, detectable cTn concentrations [> limit of detection and < upper reference limit (URL)] have increased risk of major adverse cardiovascular events (MACE) or all-cause mortality.

METHODS

A prospective 5-year follow-up of patients recruited in the emergency department with possible acute coronary syndrome (ACS) and cTn concentrations measured with hs-cTnI (Abbott) and hs-cTnT (Roche) assays. Cox regression models were generated with adjustment for covariates in those without MACE on presentation. Hazard ratios (HRs) for hs-cTn were calculated relative to the HRs at the median concentration.

RESULTS

Of 1113 patients, 836 were without presentation MACE. Of these, 138 incurred a MACE and 169 died during a median 5.8-year follow-up. HRs for MACE at the URLs were 2.3 (95% CI, 1.7-3.2) for hs-cTnI and 1.8 (95% CI, 1.3-2.4) for hs-cTnT. Corresponding HRs for mortality were 1.7 (95% CI, 1.2-2.2) for hs-cTnI and 2.3 (95 % CI, 1.7-3.1) for hs-cTnT. The HR for MACE increased with increasing hs-cTn concentration similarly for both assays, but the HR for mortality increased at approximately twice the rate for hs-cTnT than hs-cTnI. Patients with hs-cTnI ≥10 ng/L or hs-cTnT ≥16 ng/L had the same percentage of MACE at 5-year follow-up (33%) as patients with presentation MACE.

CONCLUSIONS

Many patients with ACS ruled out and putatively normal but detectable hs-cTnI concentrations are at similar long-term risk as those with MACE. hs-cTnT concentrations are more strongly associated with 5-year mortality than hs-cTnI.

The importance of low level QC for high sensitivity troponin assays

BACKGROUND

With the advent of the new high-sensitivity troponin assays, it is becoming critical to measure troponin accurately to low concentrations. To ensure assay performance is acceptable, appropriate QC must be run.

METHODS

In addition to the routine use of commercial QC material, we prepared pools of human QC material with low troponin concentrations close to the limit of quantitation, and ran these regularly on our laboratory analysers.

RESULTS

Over 3 years we found no drift or shift in our hs-cTnI assay. We found that only the very low concentration human QC material gave warning of precision problems with the hs-cTnI assay. At the time of the documented poor assay precision, the higher concentration QC material indicated satisfactory performance.

CONCLUSIONS

Choice of QC material with an appropriate concentration is important for any assay. For hs-cTn assays, it is of particular importance to use control material with a concentration near to the limit of quantitation.