A Test in Context: Interpretation of High-Sensitivity Cardiac Troponin Assays in Different Clinical Settings

Blood Biomarkers as a Non-Invasive Method for the Assessment of the State of the Fontan Circulation

The Fontan operation has become the primary palliative treatment for patients with a functionally univentricular heart. The population of patients with Fontan circulation is constantly growing and aging. As the number of Fontan patients surviving into adulthood increases, there is a clear need for research on how best to follow these patients and manage their complications. Monitoring blood biomarkers is a promising method for the non-invasive assessment of the Fontan circulation. In this article, we provide a comprehensive review of the available evidence on this topic. The following biomarkers were included: natriuretic peptides, red blood cell distribution width (RDW), cystatin C, high-sensitivity C-reactive protein, vitamin D, parathyroid hormone, von Willebrand factor, carbohydrate antigen 125, lipoproteins, hepatocyte growth factor, troponins, ST2 protein, galectin-3, adrenomedullin, endothelin-1, components of the renin-angiotensin-aldosterone system, norepinephrine, interleukin 6, tumor necrosis factor α, and uric acid. We did not find strong enough data to propose evidence-based recommendations. Nevertheless, significantly elevated levels of brain natriuretic peptide (BNP)/N-terminal prohormone of BNP (NT-proBNP) are most likely associated with the failure of the Fontan circulation. The use of the RDW is also promising. Several biomarkers appear to be useful in certain clinical presentations. Certainly, robust longitudinal, preferably multicenter, prospective studies are needed to determine the sensitivity, specificity, evidence-based cut-off values and overall predictive value of different biomarkers in monitoring Fontan physiology.

Chest Pain With Significantly Elevated Troponins: Be Wary of False Positives

High-sensitivity cardiac troponins are considered a gold standard for diagnosing acute myocardial infarction and myocardial injury. However, the occurrence of false positives needs to be kept in mind.  We describe the clinical challenges in diagnosing a 45-year-old woman who repeatedly presented to the emergency department with atypical chest pain and extremely elevated high sensitivity troponin I (HsTnI), despite normal imaging including cardiac MRIs and invasive coronary angiograms, on multiple occasions.  This report emphasizes the importance of carefully interpreting elevated troponin levels, especially when clinical findings and further investigations do not support a cardiac origin for troponin (Tn) elevation.

Valency of cystatin C and creatinine on troponin values in chronic kidney disease patients with chest pain in emergency department

OBJECTIVE

Chronic kidney disease (CKD) patients with chest pain (CP) should receive special attention in the emergency department (ED). Evaluating troponin levels is highly confusing. This study aims to compare Cystatin C (CysC) and creatinine on troponin results in CKD patients with CP in ED.

METHODS

A prospective cross-sectional study was conducted on 174 patients with CKD who were admitted to ED with CP and registered with clinicaltrials.gov (NCT05303441). Patients were risk classified. Blood samples were collected for 0th-hour, 1st-hour, and 3rd-hour troponin levels and admission CysC level. Then they were grouped as they were diagnosed with ACS or not. CKD-EPI formula was used to calculate Glomerular filtration rate (GFR) with creatinine, CysC and cyscrea for each patient (https://www.kidney.org/professionals/kdoqi/gfr_calculator).

RESULTS

The overall rate of CKD stage change calculated with creatinine to another stage with CysC was 52.87 % in all groups. There was a highly significant correlation between creatinine and CysC levels with 1st-hour and 3rd-hour troponin levels in both ACS and non-ACS groups (r = 0.809 and 0.810, respectively; r = 0.908 and 0.912, respectively). The prediction equations between creatinine, CysC, and troponin were as 0th-hour troponin = 1.553 + 1.074creatinine and 0th-hour troponin = 1.580 + 0.837cystatin C, respectively. 3rd-hour troponin level had a markedly good predictive power for ACS (AUC = 0.813, p < 0.001; sensitivity 74.7 %, specificity 74.7 %) with a cut-off value of 64.50.

CONCLUSION

CysC can be preferable in CKD patients with CP due to the stage change and the decisive effect of CysC on troponin compared to creatinine in patients with and without ACS.

Associations of elevated cardiac biomarkers with hyperuricemia and mortality in US adults without prevalent cardiovascular disease

Background

NT-proBNP (N-terminal pro-B-type natriuretic peptide), high-sensitivity cardiac troponin T (hs-troponin T), and high-sensitivity cardiac troponin I (hs-troponin I) have been widely recognized as significant cardiac biomarkers, and are increasingly being recommended for early risk identification in cardiovascular high-risk populations. The aim of our study was to evaluate the prevalence of elevated cardiac biomarkers (NT-proBNP, hs-troponin T, hs-troponin I) and their association with the risk of hyperuricemia in the general US adults without known cardiovascular disease. We further studied whether elevated cardiac biomarkers are associated with an increased risk of all-cause and cardiovascular mortality in individuals with or without hyperuricemia.

Methods

The study population came from the adults (age ≥20y) without prevalent cardiovascular disease in NHANES (National Health and Nutrition Examination Survey) 1999 to 2004. We evaluated the prevalence of elevated cardiac biomarkers among adults with or without hyperuricemia, and conducted a comprehensive multivariate logistic regression analysis to ascertain the association between elevated cardiac biomarkers and hyperuricemia risk. Multivariate Cox regression model and Kaplan-Meier curve, risk competition model and Cumulative Incidence Function(CIF) were used respectively to examine the associations between elevated cardiac biomarkers with all-cause and cardiovascular mortality.

Results

In general US adults without known cardiovascular disease, the prevalence of hyperuricemia was 16.35%. The age-adjustd prevalence of elevated NT-proBNP (≥125 pg/mL), hs-troponin T (≥6 ng/L), and hs-troponin I (male ≥6, female ≥4 ng/L) was 16.70%, 49.80%, and 11.91%, respectively, among adults with hyperuricemia. Adjusted multivariable logistic regression analysis revealed a statistically significant association between elevated levels of NT-proBNP, hs-troponin T, and hs-troponin I and hyperuricemia, and different clinical categories observed grade differences on the same cardiac biomarker. Elevated NT-proBNP, hs-troponinT and hs-troponinI were each significantly positively associated with the cumulative incidence of all-cause and cardiovascular mortality in adults with or without hyperuricemia. Compared to those with elevated cardiac biomarkers only, adults with hyperuricemia and elevated cardiac biomarkers faced the highest risk of all-cause and cardiovascular mortality.

Conclusions

Our study identified that elevated cardiac biomarkers pose a high burden on hyperuricemia risk in the general population without known cardiovascular disease, and further provides important information on long-term mortality risk in these populations. Routine testing of cardiac biomarkers may be useful for early risk identification and prognostic assessment in adults with hyperuricemia.

Comprehensive Quality Analysis of Conventional and Novel Biomarkers in Diagnosing and Predicting Prognosis of Coronary Artery Disease, Acute Coronary Syndrome, and Heart Failure, a Comprehensive Literature Review

Coronary artery disease (CAD), acute coronary syndrome (ACS), and heart failure (HF) are major global health issues with high morbidity and mortality rates. Biomarkers like cardiac troponins (cTn) and natriuretic peptides (NPs) are crucial tools in cardiology, but numerous new biomarkers have emerged, proving increasingly valuable in CAD/ACS. These biomarkers are classified based on their mechanisms, such as fibrosis, metabolism, inflammation, and congestion. The integration of established and emerging biomarkers into clinical practice is an ongoing process, and recognizing their strengths and limitations is crucial for their accurate interpretation, incorporation into clinical settings, and improved management of CVD patients. We explored established biomarkers like cTn, NPs, and CRP, alongside newer biomarkers such as Apo-A1, IL-17E, IgA, Gal-3, sST2, GDF-15, MPO, H-FABP, Lp-PLA2, and ncRNAs; provided evidence of their utility in CAD/ACS diagnosis and prognosis; and empowered clinicians to confidently integrate these biomarkers into clinical practice based on solid evidence.

Systematic Review of Sex-specific High Sensitivity Cardiac Troponin I and T Thresholds

PURPOSE

High-sensitivity cardiac troponin I (hs-cTnI) and T (hs-cTnT) have been demonstrated to have lower sex-specific 99th percentiles in healthy females. However, these sex-specific thresholds are not widely adopted in clinical practice which could lead to underdiagnosis of acute myocardial infarction in females. We conducted a systematic review to explore sex-specific 99th percentiles for hs-cTnI and hs-cTnT from healthy reference populations.

METHODS

The principles of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used to complete this systematic review. We used PubMed and OVID EMBASE to search for original studies published between November 2017 and November 2021 that included reference populations used to establish the 99th percentiles of hs-cTnI and hs-cTnT with the following inclusion criteria: adults; English language; samples taken as part of a healthy, reference population; studies using high-sensitivity troponin assay; and sample size > 300. Studies were excluded if the reference population sample size was < 300, if a conventional troponin assay was used, or if they did not include independently derived, sex-specific 99th percentiles. Data was extracted from the studies through Covidence to perform a qualitative data synthesis. Female-specific, male-specific, and overall 99th percentiles for hs-cTn were compared.

FINDINGS

We reviewed 131 articles of which 19 met inclusion criteria. These 19 studies derived sex-specific 99th percentiles for 11 different hs-cTnI assays and 9 different hs-cTnT assays. More than 90% (13 of 14 studies) of hs-cTnI assays found lower female 99th percentiles compared to male and to overall 99th percentiles. One study included nine different hs-cTnI assays, of which only one assay resulted in a higher female 99th percentile compared to male and to overall 99th percentiles. Eight of nine hs-cTnT studies (88.9%) found lower female 99th percentiles compared to male and to overall 99th percentiles.

IMPLICATIONS

The data shows significantly lower 99th percentiles in females compared to 99th percentiles in males and overall. Incorporating these sex-specific 99th percentile cut-offs into clinical practice could lead to increased diagnosis and potentially better outcomes for females presenting with acute myocardial infarction.

Screening for Heart Failure: Biomarkers to Detect Heightened Risk in the General Population

PURPOSE OF REVIEW

Heart failure (HF) represents a growing global burden of morbidity and mortality. Identifying individuals at risk for HF development is increasingly important, particularly given the advent of disease-modifying therapies for HF as well as its major risk factors such as obesity actalnd diabetes. We aim to review the key circulating biomarkers associated with future HF which may contribute to HF risk prediction.

RECENT FINDINGS

While current guidelines recommend the use of natriuretic peptides and cardiac troponins in HF risk stratification, there are a diverse array of other emerging protein, metabolic, transcriptomic, and genomic biomarkers of future HF development. These biomarkers not only lend insight into the underlying pathophysiology of HF, which spans inflammation to cardiac fibrosis, but also offer an opportunity to further refine HF risk in addition to established biomarkers. As evolving techniques in molecular biology enable an increased understanding of the complex biologic contributions to HF pathophysiology, there is an important opportunity to construct integrated clinical and multi-omic models to best capture HF risk. Moving forward, future studies should seek to understand the contributions of sex differences, underlying comorbidity burden, and HF subtypes to an individual's HF risk. Further studies are necessary to fully define the clinical utility of biomarker screening approaches to refine HF risk assessment, as well as to link risk assessment directly to preventive strategies for HF.

Influence of Sex and Cardiometabolic Risk Factors on the High-Sensitivity Cardiac Troponins at the Concentrations Used as the Thresholds for Cardiovascular Risk Stratification in a Presumably Healthy Polish Population

Background: Low but detectable cardiac troponin (cTn) concentrations may reflect cardiovascular (CV) risk in a primary prevention setting. Using previously described thresholds for CV risk stratification, we assessed the influence of sex and cardiometabolic risk factors on the concentrations of high-sensitivity cTn in presumably healthy subjects. Methods: The prospective study included 597 presumably healthy individuals (313 women, 284 men). In all participants, hs-cTnI, hs-cTnT, lipid profile, C-reactive protein, glycated hemoglobin, estimated GFR (eGFR) and B-type naturetic peptide (BNP) were measured. Subjects were categorized into two groups of CV risk, based on hs-cTn non sex-specific cut-off of 5.0 ng/L. For hs-cTnI, sex-specific cut-off values were also used: ≥4.0 ng/L for females and ≥6.0 ng/L for males. Results: Increased CV risk, indicated by hs-cTn concentrations ≥ 5.0 ng/L, was significantly associated with age > 40 years, male sex, obesity and BNP concentrations ≥ 35 ng/L. Using the same 5.0 ng/L threshold, hs-TnT classified approximately twice as many individuals into the CV subgroup compared to hs-cTnI, particularly in males (31% vs. 13%, respectively). After applying sex-specific cut-offs for hs-cTnI, the proportion of females and males with increased risk became similar (8% vs. 9%, respectively). In contrast, using non-sex-specific cut-offs for hs-cTnI resulted in a proportion of 6% for females and 13% for males. BNP and eGFR had significant impact on CV risk stratification using sex-specific cut-offs for hs-cTnI. Conclusions: Our findings suggest the necessity of using sex-specific cut-offs for hs-cTn as a cardiovascular risk marker, in addition to other cardiometabolic factors, in the general population.

High-Sensitivity Cardiac Troponin [hs-cTn] as a Valuable Biomarker for Pulmonary Hypertension Risk Stratification: A Contemporary Review of the Literature

Background: Pulmonary hypertension (PH) can lead to cardiac failure, thereby significantly affecting life expectancy and quality of life. Due to inadequate disease surveillance and risk assessment, clinical challenges persist despite advances in diagnosis and treatment. We aimed to review the potential of high-sensitivity cardiac troponin (hs-cTn) as a biomarker for predicting outcomes in PH patients. Methods: A thorough examination of the PubMed and Google Scholar databases was conducted through March 2023. Studies involving adult PH patients and hsTn as a prognostic indicator of outcomes such as mortality, hospitalization, and disease progression were included, after screening their titles and abstracts. Two independent evaluators extracted data, with the quality assessed using the JBI critical appraisal tool. Results: This review uncovered eight studies that examined the prognostic value of hs-cTn in PH patients. Higher hs-cTn levels were associated with increased mortality and hospitalization rates, according to the studies. The severity of PH, cardiac dysfunction, right ventricular function, and systolic dysfunction were associated with hs-cTn. Multiple studies have demonstrated that hsTn has the potential to identify high-risk PH patients who could benefit from targeted therapies and increased clinical monitoring. Conclusions: This review suggests that hsTn may be a biomarker for PH risk stratification and prognosis. Across PH subtypes, elevated hsTn levels predict poor outcomes. However, large-scale prospective studies are needed to confirm hs-cTn's function in diagnosing pulmonary hypertension and determine its potential value in treatment.

High-Sensitivity Troponin: Finding a Meaningful Delta

High-sensitivity cardiac troponin (hs-cTn) assays have significantly refined the resolution of biomarker-level detection and have emerged as the gold standard cardiac biomarker in evaluating myocardial injury. Since its introduction, hs-cTn has been integrated into the Fourth Universal Definition of Myocardial Infarction and various European Society of Cardiology (ESC) and American College of Cardiology/American Heart Association (ACC/AHA) guidelines for the evaluation and diagnosis of chest pain syndromes. However, despite its integral role in caring for patients with chest pain, there are still substantive gaps in our knowledge of the clinical interpretation of dynamic changes in hs-cTn values. Whether a relative or absolute hs-cTn delta should be used to detect acute myocardial injury remains debatable. There are also emerging considerations of possible sex and racial/ethnic differences in clinically significant troponin deltas. In the emergency department, there is debate about the optimal time frame to recheck hs-cTn after symptom onset for myocardial infarction rule-out and whether hs-cTn deltas should be integrated into clinical risk scores. In this review, we will provide an overview of the history of clinical utilization of cardiac biomarkers, the development of hs-cTn assays, and the ongoing search for a meaningful delta that can be clinically applicable.

Kidney function-specific cut-off values of high-sensitivity cardiac troponin T for the diagnosis of acute myocardial infarction

Background

The diagnosis of acute myocardial infarction (AMI) using high-sensitivity cardiac troponin T (hs-cTnT) remains challenging in patients with kidney dysfunction.

Methods

In this large, multicenter cohort study, a total of 20 912 adults who underwent coronary angiography were included. Kidney function-specific cut-off values of hs-cTnT were determined to improve the specificity without sacrificing sensitivity, as compared with that using traditional cut-off value (14 ng/L) in the normal kidney function group. The diagnostic accuracy of the novel cut-off values was validated in an independent validation cohort.

Results

In the derivation cohort (n = 12 900), 3247 patients had an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2. Even in the absence of AMI, 50.2% of participants with eGFR <60 mL/min/1.73 m2 had a hs-cTnT concentration ≥14 ng/L. Using 14 ng/L as the threshold of hs-cTnT for diagnosing AMI led to a significantly reduced specificity and positive predictive value in patients with kidney dysfunction, as compared with that in patients with normal kidney function. The kidney function-specific cut-off values were determined as 14, 18 and 48 ng/L for patients with eGFR >60, 60-30 and <30 mL/min/1.73 m2, respectively. Using the novel cut-off values, the specificities for diagnosing AMI in participants with different levels of kidney dysfunction were remarkably improved (from 9.1%-52.7% to 52.8-63.0%), without compromising sensitivity (96.6%-97.9%). Similar improvement of diagnostic accuracy was observed in the validation cohort (n = 8012).

Conclusions

The kidney function-specific cut-off values of hs-cTnT may help clinicians to accurately diagnose AMI in patients with kidney dysfunction and avoid the potential overtreatment in practice.

Platelets and extracellular vesicles in disease promotion via cellular cross-talk and eicosanoid biosynthesis

New insights have been gained on the role of platelets beyond thrombosis. Platelets can accumulate in damaged and inflamed tissues, acting as a sentinel to detect and repair tissue damage. However, by releasing several soluble factors, including thromboxane A2 (TXA2) and 12-hydroxyeicosatetraenoic acid, and extracellular vesicles (EVs), platelets can activate vascular cells, stromal, such as fibroblasts, immune cells, and cancer cells, leading to atherosclerosis, vascular restenosis, tissue fibrosis, and tumor metastasis. Platelet-derived extracellular vesicles (PEVs) are released when platelets are activated and can transfer their cargo to other cell types, thus contributing to the development of diseases. Inhibitors of the internalization of PEVs can potentially represent novel therapeutic tools. Both platelets and PEVs contain a significant number of different types of molecules, and their omics assessment and integration with clinical data using computational approaches have the potential to detect early disease development and monitor drug treatments.

Successful pharmaco-invasive approach using a lower alteplase dose and VA-ECMO support in high-risk pulmonary embolism: case report

Despite the elevated mortality rates associated with high-risk pulmonary embolism (PE), this condition remains understudied. Data regarding the effectiveness and safety of invasive therapies such as venoarterial extracorporeal membrane oxygenation (VA-ECMO) in this patient population remains controversial. Here, we present the case of a 61-year-old male with high-risk PE associated with refractory cardiac arrest and cardiogenic shock who underwent a combination of extracorporeal cardiopulmonary resuscitation with VA-ECMO and pharmaco-invasive therapy (mechanical thrombi fragmentation plus lower alteplase dose), resulting in successful pulmonary reperfusion. After a prolonged in-hospital stay, the patient was discharged in stable condition.

Barbed arrow-like structure membrane with ultra-high rectification coefficient enables ultra-fast, highly-sensitive lateral-flow assay of cTnI

Acute myocardial infarction (AMI) has become a public health disease threatening public life safety due to its high mortality. The lateral-flow assay (LFA) of a typical cardiac biomarker, troponin I (cTnI), is essential for the timely warnings of AMI. However, it is a challenge to achieve an ultra-fast and highly-sensitive assay for cTnI (hs-cTnI) using current LFA, due to the limited performance of chromatographic membranes. Here, we propose a barbed arrow-like structure membrane (BAS Mem), which enables the unidirectional, fast flow and low-residual of liquid. The liquid is rectified through the forces generated by the sidewalls of the barbed arrow-like grooves. The rectification coefficient of liquid flow on BAS Mem is 14.5 (highest to date). Using BAS Mem to replace the conventional chromatographic membrane, we prepare batches of lateral-flow strips and achieve LFA of cTnI within 240 s, with a limit of detection of 1.97 ng mL-1. The lateral-flow strips exhibit a specificity of 100%, a sensitivity of 93.3% in detecting 25 samples of suspected AMI patients. The lateral-flow strips show great performance in providing reliable results for clinical diagnosis, with the potential to provide early warnings for AMI.

Role of Antitroponin Antibodies and Macrotroponin in the Clinical Interpretation of Cardiac Troponin

Cardiac troponin is extensively used as a biomarker in modern medicine due to its diagnostic capability for myocardial injury, as well as its predictive and prognostic value for cardiac diseases. However, heterophile antibodies, antitroponin antibodies, and macrotroponin complexes can be observed both in seemingly healthy individuals and patients with cardiac diseases, potentially leading to false positive or disproportionate elevation of cTn (cardiac troponin) assay results and introducing discrepancies in clinical interpretations with impact on medical management. In this review article, we describe the possible mechanisms of cTn release and the sources of variations in the assessment of circulating cTn levels. We also explore the pathophysiological mechanisms underlying antitroponin antibody development and discuss the influence exerted by macrotroponin complexes on the results of immunoassays. Additionally, we explore approaches to detect these complexes by presenting various clinical scenarios encountered in routine clinical practice. Finally, unsolved questions about the development, prevalence, and clinical significance of cardiac autoantibodies are discussed.

Clinical Implications of High-Sensitivity Troponin Elevation Levels in Non-ST-Segment Elevation Myocardial Infarction Patients: Beyond Diagnostics

Standard troponin has long been pivotal in diagnosing coronary syndrome, especially Non-ST-Segment Elevation Myocardial Infarction (NSTEMI). The recent introduction of high-sensitivity troponin (hs-cTnI) has elevated it to the gold standard. Yet, its nuanced role in predicting angiographic lesions and clinical outcomes, notably in specific populations like obesity, remains underexplored. Aim: To evaluate the association between hs-cTnI magnitude in NSTEMI patients and angiographic findings, progression to acute heart failure, and its performance in obesity. Methods: Retrospective study of 208 NSTEMI patients at a large university center (2020-2023). Hs-cTnI values were assessed for angiographic severity, acute heart failure, and characteristics in the obese population. Data collected and diagnostic performance were evaluated using manufacturer-specified cutoffs. Results: 97.12% of patients had a single culprit vessel. Hs-cTnI elevation correlated with angiographic stenosis severity. Performance for detecting severe coronary disease was low, with no improvement using a higher cutoff. No association was found between hs-cTnI and the culprit vessel location. Hs-cTnI did not predict acute heart failure progression. In the obese population, hs-cTnI levels were higher, but acute heart failure occurred less frequently than in non-obese counterparts. Conclusions: In NSTEMI, hs-cTnI elevation is associated with significant stenosis, but not with location or acute heart failure. Obesity correlates with higher hs-cTnI levels but a reduced risk of acute heart failure during NSTEMI.

High-sensitivity cardiac troponin I for cardiovascular risk stratification in apparently healthy individuals

Troponin I and T as cardiac-specific biomarkers are highly useful tools not only in the diagnosis of acute coronary syndromes but also as independent predictors of several other clinical conditions. High-sensitivity cardiac troponin (hs-cTn) assays allow the detection of considerably low concentrations of cardiac troponin in apparently healthy and asymptomatic individuals, being a candidate tool for cardiovascular risk stratification in the general population. A group of Greek experts summarized the bulk of evidence regarding the use of hs-cTnI as a predictor of cardiovascular events and mortality in apparently healthy individuals and its additive value on top of existing risk stratification methods. This document could serve as a guide for the incorporation of hs-cTnI as an additional risk stratification tool in cardiovascular prevention strategies in apparently healthy individuals.

High-Sensitivity vs Conventional Troponin Cutoffs for Risk Stratification in Patients With Acute Pulmonary Embolism

Importance

High-sensitivity troponin tests can detect even milder cardiac troponin elevations in plasma, beyond the threshold of conventional troponin tests. Whether detection of low-grade cardiac troponin elevation is associated with outcomes of patients with hemodynamically stable pulmonary embolism (PE) and helps with risk stratification is unknown.

Objective

To determine the association between high-sensitivity cardiac troponin I (hs-cTnI) compared with conventional cardiac troponin I (cTnI) and PE risk designations according to the European Society of Cardiology (ESC) 2019 classification scheme and clinical outcomes in patients with hemodynamically stable PE.

Design, Setting, and Participants

This is a post hoc analysis of data from the prospective Prognostic Value of Computed Tomography (PROTECT) multicenter cohort study enrolling patients from 12 hospital emergency departments in Spain. In this analysis, cTnI and hs-cTnI were compared with respect to ESC risk designation, and the association between troponin values and a complicated course after PE diagnosis was evaluated. Of 848 patients enrolled in PROTECT, 834 (98.3%) had hsTnI and cTnI values available and were included in the present analysis. Data were analyzed from May to December 2022.

Exposures

Troponin blood testing with cTnI (threshold of >0.05 ng/mL) vs hs-cTnI (threshold of >0.029 ng/mL) assays at the time of PE diagnosis.

Main Outcomes

Complicated course, defined as hemodynamic collapse, recurrent PE, or all-cause death, within 30 days after PE.

Results

Of 834 patients (mean [SEM] age, 67.5 [0.6] years; 424 [50.8%] female), 139 (16.7%) had elevated cTnI and 264 (31.7%) elevated hs-TnI, respectively. During follow-up, 62 patients (7.4%; 95% CI, 5.7-9.4) had a complicated course. Analyzing troponin elevation as a binary variable, elevated cTnI (odds ratio [OR], 2.84; 95% CI, 1.62-4.98) but not hs-cTnI (OR, 1.12; 95% CI, 0.65-1.93) was associated with increased odds of a complicated course. Of 125 patients who had elevated hs-cTnI but normal cTnI, none (0; 95% CI, 0.0-2.9) developed a complicated course. Using the 2019 ESC risk stratification scheme, hs-TnI classified fewer patients as low risk compared with cTnI. Among 78 patients designated as ESC low risk when using cTnI but not with hsTnI, none (0; 95% CI, 0.0-4.6) had a complicated course.

Conclusions and Relevance

In this study of patients with hemodynamically stable PE, hs-cTnI identified modest elevations in cardiac troponin levels. However, the results did not provide additive clinical value compared with cTnI. These findings suggest that use of hs-cTnI may result in overestimation of the risk in patients with stable PE.

Chronic Kidney Disease Associated with Ischemic Heart Disease: To What Extent Do Biomarkers Help?

Chronic kidney disease represents a complex and multifaceted pathology characterized by the presence of structural or functional renal anomalies associated with a persistent reduction in renal function. As the disease progresses, complications arise due to the chronic inflammatory syndrome, hydro-electrolytic disorders, and toxicity secondary to the uremic environment. Cardiovascular complications are the leading cause of death for these patients. Ischemic cardiac pathology can be both a consequence and complication of chronic kidney disease, highlighting the need to identify specific cardiorenal dysfunction biomarkers targeting pathophysiological mechanisms common to both conditions. This identification is crucial for establishing accurate diagnoses, prognoses, and risk stratifications for patients. This work is intended to elucidate the intricate relationship between chronic kidney disease and ischemic heart disease and to investigate the roles of cardiorenal biomarkers, including cardiac troponin, natriuretic peptides, galectin-3, copeptin, fibroblast growth factor 23 and its co-receptor Klotho, soluble suppression of tumorigenicity 2, and plasma growth differentiation factor 15.

Selective MCL-1 inhibitor ABBV-467 is efficacious in tumor models but is associated with cardiac troponin increases in patients

BACKGROUND

MCL-1 is a prosurvival B-cell lymphoma 2 family protein that plays a critical role in tumor maintenance and survival and can act as a resistance factor to multiple anticancer therapies. Herein, we describe the generation and characterization of the highly potent and selective MCL-1 inhibitor ABBV-467 and present findings from a first-in-human trial that included patients with relapsed/refractory multiple myeloma (NCT04178902).

METHODS

Binding of ABBV-467 to human MCL-1 was assessed in multiple cell lines. The ability of ABBV-467 to induce tumor growth inhibition was investigated in xenograft models of human multiple myeloma and acute myelogenous leukemia. The first-in-human study was a multicenter, open-label, dose-escalation study assessing safety, pharmacokinetics, and efficacy of ABBV-467 monotherapy.

RESULTS

Here we show that administration of ABBV-467 to MCL-1-dependent tumor cell lines triggers rapid and mechanism-based apoptosis. In vivo, intermittent dosing of ABBV-467 as monotherapy or in combination with venetoclax inhibits the growth of xenografts from human hematologic cancers. Results from a clinical trial evaluating ABBV-467 in patients with multiple myeloma based on these preclinical data indicate that treatment with ABBV-467 can result in disease control (seen in 1 patient), but may also cause increases in cardiac troponin levels in the plasma in some patients (seen in 4 of 8 patients), without other corresponding cardiac findings.

CONCLUSIONS

The selectivity of ABBV-467 suggests that treatment-induced troponin release is a consequence of MCL-1 inhibition and therefore may represent a class effect of MCL-1 inhibitors in human patients.

Use of 3D Printing Techniques to Fabricate Implantable Microelectrodes for Electrochemical Detection of Biomarkers in the Early Diagnosis of Cardiovascular and Neurodegenerative Diseases

This Review provides a comprehensive overview of 3D printing techniques to fabricate implantable microelectrodes for the electrochemical detection of biomarkers in the early diagnosis of cardiovascular and neurodegenerative diseases. Early diagnosis of these diseases is crucial to improving patient outcomes and reducing healthcare systems' burden. Biomarkers serve as measurable indicators of these diseases, and implantable microelectrodes offer a promising tool for their electrochemical detection. Here, we discuss various 3D printing techniques, including stereolithography (SLA), digital light processing (DLP), fused deposition modeling (FDM), selective laser sintering (SLS), and two-photon polymerization (2PP), highlighting their advantages and limitations in microelectrode fabrication. We also explore the materials used in constructing implantable microelectrodes, emphasizing their biocompatibility and biodegradation properties. The principles of electrochemical detection and the types of sensors utilized are examined, with a focus on their applications in detecting biomarkers for cardiovascular and neurodegenerative diseases. Finally, we address the current challenges and future perspectives in the field of 3D-printed implantable microelectrodes, emphasizing their potential for improving early diagnosis and personalized treatment strategies.

One-pot synthesis of AuPt@FexOy nanoparticles with excellent peroxidase-like activity for development of ultrasensitive colorimetric lateral flow immunoassay of cardiac troponin I

Detection of cardiac troponin I (cTnI) plays a critical role in diagnosing acute myocardial infarction (AMI). In this report, a new kind of spherical AuPt@FexOy core@shell nanoparticles (termed as AuPt@FexOy NPs) were one-pot synthesized by a redox interaction-engaged strategy (RIES) without the addition of any surfactants or reducing agents. The as-synthesized AuPt@FexOy NPs not only retain the plasmonic activity of gold nanoparticles (AuNPs), but also possess excellent catalytic activities of platinum nanoparticles (PtNPs) and FexOy nanoclusters. The features of AuPt@FexOy NPs enable greatly enhance the colorimetric detection sensitivity of lateral flow immunoassay (LFIA) through integrating AuPt@FexOy NPs labeling procedure and catalyzing oxidation of chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) signal amplification strategy. The as-developed colorimetric LFIA (termed as AuPt@FexOy-LFIA) exhibits the limit of detection (LOD) as 26.0 pg mL-1 cTnI under the TMB signal amplification mode. In particular, the detection results of cTnI in 40 clinical seral samples by AuPt@FexOy-LFIA are correlated well with those of cTnI in the same samples by commercial enzyme-linked immunosorbent assay (ELISA) detection kit (R2 = 0.97, slope = 1), demonstrating the highly reliable analytical performance and good application prospect of AuPt@FexOy-LFIA.

High-sensitivity troponins and mortality in the general population

AIMS

Cardiac troponin T and I can be measured using a number of high-sensitivity (hs) assays. This study aimed to characterize correlations between four such assays and test their comparative associations with mortality.

METHODS AND RESULTS

Among adults without cardiovascular disease in the 1999-2004 National Health and Nutrition Examination Survey, hs-troponin T was measured using one assay (Roche) and hs-troponin I using three assays (Abbott, Siemens, and Ortho). Cox regression was used to estimate associations with all-cause and cardiovascular mortality. Pearson's correlation coefficients comparing concentrations from each assay ranged from 0.53 to 0.77. There were 2188 deaths (488 cardiovascular) among 9810 participants. Each hs-troponin assay [log-transformed, per 1 standard deviation (SD)] was independently associated with all-cause mortality: hazard ratio (HR) 1.20 [95% confidence interval (CI) 1.13-1.28] for Abbott hs-troponin I; HR 1.10 (95% CI 1.02-1.18) for Siemens hs-troponin I; HR 1.23 (95% CI 1.14-1.33) for Ortho hs-troponin I; and HR 1.31 (95% CI 1.21-1.42) for Roche hs-troponin T. Each hs-troponin assay was also independently associated with cardiovascular mortality (HR 1.44 to 1.65 per 1 SD). Associations of hs-troponin T and all-cause and cardiovascular mortality remained significant after adjusting for hs-troponin I. Furthermore, associations of hs-troponin I remained significant after mutually adjusting for hs-troponin I from the other individual assays: e.g. cardiovascular mortality HR 1.46 (95% CI 1.19-1.79) for Abbott after adjustment for the Siemens assay and HR 1.29 (95% CI 1.09-1.53) for Abbott after adjustment for the Ortho assay.

CONCLUSION

This study demonstrates only modest correlations between hs-troponin T and three hs-troponin I assays and that hs-troponin I assays can provide distinct risk information for mortality in the general population.

The use of intraoperative transit time flow measurement can reduce postoperative myocardial injury

OBJECTIVE

This study investigates the relationship between the use of transit time flow measurement (TTFM) and postoperative myocardial injury in off-pump coronary artery bypass grafting (OPCABG).

METHODS

In this retrospective study, we collected basic data from patients hospitalized for OPCABG in the Department of Cardiothoracic Surgery, Changzhou Second People's Hospital Affiliated with Nanjing Medical University. According to the academic research consortium (ARC)-2 definition of significant myocardial injury, we used cardiac troponin I >2380 ng/L as a criterion for significant postoperative myocardial injury. We use logistic regression and forest plots to assess the association of TTFM use with myocardial injury outcomes.

RESULTS

One hundred and forty-six patients were included in this study. The overall median age of these patients was 65.05 years, and 32 (21.92%) experienced a postoperative myocardial injury. TTFM was independently associated with the incidence of postoperative myocardial injury (odds ratio = 0.34 [95% confidence interval = 0.15-0.78]; p = .01), and we found similar trends in regression analyses across subgroups of sex, age, number of bridging vessels, hypertension, diabetes mellitus, BMI, and percutaneous coronary revascularization. One hundred and six patients were followed for 1-year vessel permeability, and seven patients (6.6%) were occluded.

CONCLUSIONS

The use of TTFM is independently associated with a reduced incidence of postoperative myocardial lesions during off-pump coronary bypass surgery. The TTFM procedure in OPCABG deserves to be actively promoted to reduce the incidence of postoperative myocardial injury.

Prognostic Value of High-Sensitivity Cardiac Troponin in Women

High-sensitivity cardiac troponin assays have become the gold standard for diagnosing acute and chronic myocardial injury. The detection of troponin levels beyond the 99th percentile is included in the fourth universal definition of myocardial infarction, specifically recommending the use of sex-specific thresholds. Measurable concentrations below the proposed diagnostic thresholds have been shown to inform prognosis in different categories of inpatients and outpatients. However, clinical investigations from the last twenty years have yielded conflicting results regarding the incremental value of using different cut-offs for men and women. While advocates of a sex-specific approach claim it may help reduce gender bias in cardiovascular medicine, particularly in acute coronary syndromes, other groups question the alleged incremental diagnostic and prognostic value of sex-specific thresholds, ultimately asserting that less is more. In the present review, we aimed to synthesize our current understanding of sex-based differences in cardiac troponin levels and to reappraise the available evidence with regard to (i) the prognostic significance of sex-specific diagnostic thresholds of high-sensitivity cardiac troponin assays compared to common cut-offs in both men and women undergoing cardiovascular disease risk assessment, and (ii) the clinical utility of high-sensitivity cardiac troponin assays for cardiovascular disease prevention in women.

Association of High-Sensitivity Troponin T and I Blood Concentrations With All-Cause Mortality and Cardiovascular Outcome in Stable Patients-Results From the INTERCATH Cohort

Background The association between high-sensitivity troponin T (hsTnT) and high-sensitivity troponin I (hsTnI) and outcome when adjusted for confounders including the angiographical severity of coronary artery disease (CAD) remains largely unknown. We therefore aimed to explore whether hsTnT and hsTnI blood levels increase with CAD severity and add independent predictive information for future major adverse cardiovascular events and all-cause mortality in stable patients. Methods and Results Patients from the INTERCATH cohort with available coronary angiography and hsTnT and hsTnI concentrations were included. Troponin concentrations were quantified via hsTnT (Roche Elecsys) and hsTnI (Abbott ARCHITECT STAT). To investigate the association of hsTnT and hsTnI with outcome, a multivariable analysis adjusting for classical cardiovascular risk factors, low-density lipoprotein cholesterol, estimated glomerular filtration rate, hs-CRP (high-sensitivity C-reactive protein), NT-proBNP (N-terminal pro-brain natriuretic peptide), and Gensini score was carried out. Of 1829 patients, 27.9% were women, and the mean age was 68.6±10.9 years. Troponin blood concentrations were higher in patients with diagnosed CAD compared with those without. Using a linear regression model current smoking, arterial hypertension, estimated glomerular filtration rate, hs-CRP, NT-proBNP, and CAD severity as graded by the Gensini and SYNTAX scores were associated with high-sensitivity troponin levels. Patients were followed for 4.4 years (25th and 75th percentiles: 4.3, 4.4). After multivariable adjustment, all-cause mortality was predicted by hsTnT (hazard ratio [HR], 1.7 [95% CI, 1.5-2.2], P<0.001) as well as hsTnI (HR, 1.5 [95% CI, 1.2-1.8], P<0.001). However, only hsTnI (HR, 1.2 [95% CI, 1.0-1.4], P=0.032) remained as an independent predictor of major adverse cardiovascular events after adjusting for most possible confounders, including CAD severity (hsTnT: HR, 1.0 [95% CI, 0.9-1.2], P=0.95). Conclusions After adjusting for classical cardiovascular risk factors, low-density lipoprotein cholesterol, estimated glomerular filtration rate, hs-CRP, NT-proBNP, and CAD severity, hsTnT and hsTnI were independently associated with all-cause mortality, but only hsTnI was associated with major adverse cardiovascular events in stable patients undergoing coronary angiography. Registration URL: https://clinicaltrials.gov/; Unique identifier: NCT04936438.

Prognosis is worse with elevated cardiac troponin in nonacute coronary syndrome compared with acute coronary syndrome

BACKGROUND

Cardiac troponin (cTn) can be elevated in many patients presenting to the emergency department (ED) with chest pain but without a diagnosis of acute coronary syndrome (ACS). We compared the prognostic significance of cTn in these different populations.

METHODS

We retrospectively analyzed the CHOPIN study, which enrolled patients who presented to the ED with chest pain. Patients were grouped as ACS, non-ACS cardiovascular disease, noncardiac chest pain and chest pain not otherwise specified (NOS). We examined the prognostic ability of cTnI for the clinical endpoints of mortality and major adverse cardiovascular event (MACE; a composite of acute myocardial infarction, unstable angina, revascularization, reinfarction, and congestive heart failure and stroke) at 180-day follow-up.

RESULTS

Among 1982 patients analyzed, 14% had ACS, 21% had non-ACS cardiovascular disease, 31% had a noncardiac diagnosis and 34% had chest pain NOS. cTnI elevation above the 99th percentile was observed in 52, 18, 6 and 7% in these groups, respectively. cTnI elevation was associated with mortality and MACE, and their relationships were more prominent in noncardiac diagnosis and chest pain NOS than in ACS and non-ACS cardiovascular diagnoses for mortality, and in non-ACS patients than in ACS patients for MACE (hazard ratio for doubling of cTnI 1.85, 2.05, 8.26 and 4.14, respectively; P for interaction 0.011 for mortality; 1.04, 1.23, 1.54 and 1.42, respectively; P for interaction <0.001 for MACE).

CONCLUSION

In patients presenting to the ED with chest pain, cTnI elevation was associated with a worse prognosis in non-ACS patients than in ACS patients.

High sensitivity cardiac troponin, a cardiac marker predicting death in patients with kidney disease: a dose-response Meta-analysis of cohort studies

BACKGROUND

Patients with kidney disease are at increased risk of adverse mortality events. Numerous studies have demonstrated the positive association of high sensitivity cardiac troponin T (hs-cTnT) and I (hs-cTnI) with all-cause and cardiovascular (CV) mortality in patients with kidney disease; however, the dose-response meta-analysis have not been reported. We therefore performed this study to evaluate the dose-response associations of hs-cTn with risk of all-cause and CV mortality to improve risk stratification.

METHODS

We searched three databases (PubMed, Embase, and Web of Science) to identify relevant prospective cohort studies published up to January 12, 2021. Random-effects models were used to summarize relative risks (RRs) and 95% confidence intervals (CIs) of all-cause and CV mortality. Restricted cubic splines were used to fit the dose-response associations.

RESULTS

For each 10 ng/L increase in hs-cTnT and hs-cTnI, the risk increased by 14% (RR = 1.14, 95% CI, 1.10-1.18) and 19% (RR = 1.19, 95% CI, 1.09-1.31) for all-cause mortality, 25% (RR = 1.25, 95% CI, 1.13-1.38) and 19% (RR = 1.19, 95% CI, 1.10-1.29) for CV mortality. A linear trend was found between hs-cTnT and all-cause mortality, whereas a non-linear trend was found in hs-cTnI. Additionally, both hs-cTnT and hs-cTnI were shown to have linear trends with CV mortality.

CONCLUSION

Our meta-analysis suggests that hs-cTn had high sensitivity in predicting mortality events. All dose-response trends were rising rather than falling, conferring that any increase in the levels of hs-cTn may possibly predict a death prognosis among CKD patients.

Editor-in-Chief's Top Picks From 2021

Each week, I record audio summaries for every paper in JACC, as well as an issue summary. This process has become a true labor of love due to the time they require, but I am motivated by the sheer number of listeners (16M+), and it has allowed me to familiarize myself with every paper that we publish. Thus, I have selected the top 100 papers (both Original Investigations and Review Articles) from distinct specialties each year. In addition to my personal choices, I have included papers that have been the most accessed or downloaded on our websites, as well as those selected by the JACC Editorial Board members. In order to present the full breadth of this important research in a consumable fashion, we will present these abstracts in this issue of JACC, as well as their Central Illustrations and podcasts. The highlights comprise the following sections: Artificial Intelligence & Machine Learning (NEW section), Basic & Translational Research, Biomarkers (NEW section), Cardiac Failure & Myocarditis, Cardiomyopathies & Genetics, Cardio-Oncology, Cardiovascular Disease in Women, Coronary Disease & Interventions, Congenital Heart Disease, Coronavirus, Hypertension, Imaging, Metabolic & Lipid Disorders, Neurovascular Disease & Dementia, Promoting Health & Prevention, Rhythm Disorders & Thromboembolism, Vascular Medicine, and Valvular Heart Disease.^1-100.

Inflammation and Cardiovascular Disease Associated With Hemodialysis for End-Stage Renal Disease

Chronic kidney disease (CKD) and cardiac insufficiency often co-exist, particularly in uremic patients on hemodialysis (HD). The occurrence of abnormal renal function in patients with cardiac insufficiency is often indicative of a poor prognosis. It has long been established that in patients with cardiac insufficiency, poorer renal function tends to indicate poorer cardiac mechanics, including left atrial reserve strain, left ventricular longitudinal strain, and right ventricular free wall strain (Unger et al., Eur J Heart Fail, 2016, 18(1), 103-12). Similarly, patients with chronic kidney disease, particularly uremic patients on HD, often have cardiovascular complications in addition to abnormal endothelial function with volume overload, persistent inflammatory states, calcium overload, and imbalances in redox responses. Cardiac insufficiency due to uremia is therefore mainly due to multifaceted non-specific pathological changes rather than pure renal insufficiency. Several studies have shown that the risk of adverse cardiovascular events is greatly increased and persistent in all patients treated with HD, especially in those who have just started HD treatment. Inflammation, as an important intersection between CKD and cardiovascular disease, is involved in the development of cardiovascular complications in patients with CKD and is indicative of prognosis (Chan et al., Eur Heart J, 2021, 42(13), 1244-1253). Therefore, only by understanding the mechanisms underlying the sequential development of inflammation in CKD patients and breaking the vicious circle between inflammation-mediated renal and cardiac insufficiency is it possible to improve the prognosis of patients with end-stage renal disease (ESRD). This review highlights the mechanisms of inflammation and the oxidative stress that co-exists with inflammation in uremic patients on dialysis, as well as the mechanisms of cardiovascular complications in the inflammatory state, and provides clinical recommendations for the anti-inflammatory treatment of cardiovascular complications in such patients.

Increased level of cardiac troponin I determined by a highly sensitive method: clinical significance beyond the assessment of the severity and prognosis of acute and chronic diseases

See: Shalnova S. A., Drapkina O. M., Kontsevaya A. V., Yarovaya E. B., Kutsenko V. A., Metelskaya V. A., Kapustina A. V., Balanova Yu. A., Litinskaya O. A., Pokrovskaya M. S. Pilot project to study the association of troponin I with cardiovascular events in the population of Russian region in Original articles, pp. 185-192.