Stable High-Sensitivity Cardiac Troponin T Levels and Outcomes in Patients With Chest Pain

Diagnosing Myocardial Injury in an Acute Chest Pain Cohort; Long-Term Prognostic Implications of Cardiac Troponin T and I

BACKGROUND

There are limited data regarding the utility of follow-up cardiac troponin (cTn) measurements after admission for acute chest pain and how long-term stability of myocardial injury and prognostic value differ when using cardiac troponin T (cTnT) or I (cTnI).

METHODS

We measured high-sensitivity (hs)-cTnT (Roche Diagnostics) and hs-cTnI (Siemens Healthineers) during hospitalization for acute chest pain and after 3 months. Acute myocardial injury was defined as concentrations > sex-specific upper reference limit (URL) during hospitalization and ≤URL at 3-months. Chronic myocardial injury (CMI) was defined as concentrations > URL at both time points. Patients were followed from the 3-month sampling point for a median of 1586 (IQR 1161-1786) days for a primary composite endpoint of all-cause mortality, myocardial infarction (MI), revascularization, and heart failure, and a secondary endpoint of all-cause mortality.

RESULTS

Among 754 patients, 33.8% (hs-cTnT) and 19.2% (hs-cTnI) had myocardial injury during hospitalization. The rate of CMI was 5 times higher by hs-cTnT (20%) assay than hs-cTnI (4%), while acute myocardial injury was equally common; 14% (hs-cTnT) and 15% (hs-cTnI), respectively (6% and 5% when excluding index non-ST-elevation MI (NSTEMI). For hs-cTnT, peak index concentration, 3-month concentration and classification of CMI predicted the primary endpoint; hazard ratios (HRs) 1.38 (95% CI 1.20-1.58), 2.34 (1.70-3.20), and 2.31 (1.30-4.12), respectively. For hs-cTnI, peak index concentration predicted the primary endpoint; HR 1.14 (1.03-1.25). This association was nonsignificant after excluding index NSTEMI.

CONCLUSIONS

Acute myocardial injury is equally frequent, whereas CMI is more prevalent using hs-cTnT assay than hs-cTnI. Measuring hs-cTnT 3 months after an acute chest pain episode could assist in further long-term risk assessment. ClinicalTrials.gov Registration Number: NCT02620202.

Acute Kidney Injury and High-Sensitivity Cardiac Troponin T Levels in the Emergency Department

Importance

The clinical implications of high-sensitivity cardiac troponin T (hs-cTnT) measurements in patients with acute kidney injury (AKI) in the emergency department (ED) are largely unknown.

Objectives

To investigate associations between serum creatinine (SCr) concentrations and hs-cTnT kinetics, as well as the clinical accuracy of hs-cTnT for myocardial infarction (MI) in patients with AKI.

Design, Setting, and Participants

This retrospective cohort study included 15 111 patient visits to 7 EDs in Sweden from December 9, 2010, to August 31, 2017, by patients 18 years or older fulfilling AKI criteria with 2 or more SCr measurements and 1 or more hs-cTnT measurement. Statistical analysis was performed from October 2, 2022, to September 28, 2023.

Exposure

Dynamic change in SCr during the ED visits.

Main Outcomes and Measures

Linear mixed-effects models were used to estimate the log-linear regression of kinetic change in hs-cTnT. Logistic regression models were applied to calculate odds ratios (ORs) for change in hs-cTnT indicating acute myocardial injury (Δhs-cTnT >20% and elevated hs-cTnT >14 ng/L) in association with change in SCr, and to assess the diagnostic performance of hs-cTnT for MI in patients with chest pain.

Results

There was a total of 15 211 visits by 13 638 patients (median age, 74 years [IQR, 64-83 years]; 8709 men [57%]), of whom 1174 (8%) had an MI. Overall, 11 353 of patients at 14 037 visits without an MI diagnosis (81%) had myocardial injury, and 4396 patients at 14 037 visits (31%) had acute myocardial injury. The change in hs-cTnT among patients without MI was 1.8-fold higher in the highest vs the lowest change in SCr quartile (64.7% [95% CI, 58.4%-71.5%] vs 36.3% [95% CI, 32.4%-40.7%]; exponentiated β coefficient, 1.78 [95% CI, 1.62-1.96]). Patients in the former group were twice as likely to have acute myocardial injury (39% [1378 of 3516 visits] vs 23% [817 of 3507 visits]; adjusted OR, 2.32 [95% CI, 2.08-2.59]). Using a 0 hours hs-cTnT cutoff value of 52 ng/L or higher assigned 627 of 2388 patients (26%) with chest pain to a high-risk group in whom the specificity and positive predictive value for MI was low (78.5% [95% CI, 76.7%-80.2&] and 27.6% [95% CI, 24.1%-31.3%], respectively).

Conclusions and Relevance

This cohort study of patients in the ED suggests that dynamic change in SCr among patients with AKI was associated with hs-cTnT concentrations indicative of acute myocardial injury. These observations were accompanied by poor performance of recommended hs-cTnT-based algorithms for MI risk stratification.

Long-term prognosis of low high-sensitivity cardiac troponin T in the emergency department compared with the general population

BACKGROUND

Long-term prognosis associated with low-high-sensitivity cardiac troponin T (hs-cTnT) concentrations in patients with chest pain is unknown. We investigated these prognostic implications compared with the general population.

METHODS

All first visits to seven emergency departments (ED)s in Sweden were included from 9 December 2010 to 31 August, 2017 by patients presenting with chest pain and at least one hs-cTnT measured. Patients with myocardial injury (any hs-cTnT >14 ng/L), including patients with myocardial infarction (MI) were excluded. Standardised mortality ratios (SMRs) and standardised incidence ratios (SIRs) were calculated as the ratio of the number of observed to expected events. The expected number was computed by multiplying the 1-year calendar period-specific, age-specific and sex-specific follow-up time in the cohort with the corresponding incidence in the general population. HRs were calculated for all-cause mortality and major adverse cardiovascular events (MACE), defined as acute MI, heart failure hospitalisation, cerebrovascular stroke or cardiovascular death, between patients with undetectable (<5 ng/L) and low (5-14 ng/L) hs-cTnT.

RESULTS

A total of 1 11 916 patients were included, of whom 69 090 (62%) and 42 826 (38%) had peak hs-cTnT concentrations of <5 and 5-14 ng/L. Patients with undetectable peak hs-cTnT had a lower mortality risk compared with the general Swedish population (SMR 0.83, 95% CI 0.79 to 0.87), with lower risks observed in all patients ≥65 years of age, but a slightly higher risk of being diagnosed with a future MI (SIR 1.39, 95% CI 1.32 to 1.47). The adjusted risk of a first MACE associated with low versus undetectable peak hs-cTnT was 1.6-fold (HR 1.61, 95% CI 1.53 to 1.70).

CONCLUSION

Patients with chest pain and undetectable hs-cTnT have an overall lower risk of death compared with the general population, with risks being highly age dependent. Detectable hs-cTnT concentrations are still associated with increased long-term cardiovascular risks.

High-Sensitivity Cardiac Troponins in Patients With Chest Pain and Treatment With Oral Antineoplastic Agents Associated With Cardiovascular Toxicity

BACKGROUND

Knowledge is limited on the clinical implications of high-sensitivity cardiac troponin (hs-cTn) measurements in patients treated with oral antineoplastic agents associated with cardiovascular side effects. This study investigated the diagnostic performance of hs-cTnT for myocardial infarction.

METHODS

Among all visits to 7 different emergency departments (EDs) from December 9, 2010 to August 31, 2017, we included visits by patients presenting with chest pain who had ≥1 hs-cTnT measured. Patients treated with oral antineoplastic agents associated with cardiovascular toxicity were identified. Logistic regression models were used to estimate the performance of hs-cTnT for diagnosing myocardial infarction.

RESULTS

We identified 214,165 visits, of which 2695 (1.3%) occurred in patients with oral antineoplastic treatment associated with cardiovascular toxicity. Treatment was associated with a higher myocardial infarction incidence (8.2% vs 5.7%), but the overall diagnostic accuracy for a myocardial infarction was lower in patients with versus without treatment, paralleled by a lower specificity and PPV with the 0 h hs-cTnT rule-in cut-off of 52 ng/L (92.6% [95% CI: 91.6-93.6] vs 96.8% [95% CI: 96.8-96.9], and 42.8 [95% CI: 37.4-48.2] vs 49.5 [95% CI: 48.6-50.4], respectively). The majority (72%) of patients with treatment were assigned to an intermediate risk group, in whom the risk of myocardial infarction was reduced by 29% (OR 0.71, 95% CI: 0.57-0.89).

CONCLUSIONS

Diagnostic accuracy of hs-cTnT for myocardial infarction is reduced among patients on treatment with oral antineoplastic agents associated with cardiovascular toxicity. Most patients would be assigned to an intermediate risk group, in whom only 4% will have a final myocardial infarction diagnosis.

Detectable troponin below the 99th percentile predicts survival in patients undergoing coronary angiography

Background

Cardiac troponin I (cTnI) above the 99th percentile is associated with an increased risk of major adverse events. Patients with detectable cTnI below the 99th percentile are a heterogeneous group with a less well-defined risk profile. The purpose of this study is to investigate the prognostic relevance of detectable cTnI below the 99th percentile in patients undergoing coronary angiography.

Methods

The study included 14,776 consecutive patients (mean age of 65.4 ± 12.7 years, 71.3 % male) from the Essen Coronary Artery Disease (ECAD) registry. Patients with cTnI levels above the 99th percentile and patients with ST-segment elevation acute myocardial infarction were excluded. All-cause mortality was defined as the primary endpoint.

Results

Detectable cTnI below the 99th percentile was present in 2811 (19.0 %) patients, while 11,965 (81.0 %) patients were below detection limit of the employed assay. The mean follow-up was 4.25 ± 3.76 years. All-cause mortality was 20.8 % for patients with detectable cTnI below the 99th percentile and 15.0 % for those without detectable cTnI. In a multivariable Cox regression analysis, detectable cTnI was independently associated with all-cause mortality with a hazard ratio of 1.60 (95 % CI 1.45-1.76; p < 0.001). There was a stepwise relationship with increasing all-cause mortality and tertiles of detectable cTnI levels with hazard ratios of 1.63 (95 % CI 1.39-1.90) for the first tertile to 2.02 (95 % CI 1.74-2.35) for the third tertile.

Conclusions

Detectable cTnI below the 99th percentile is an independent predictor of mortality in patients undergoing coronary angiography with the risk of death growing progressively with increasing troponin levels.

Intrapartum trends of NT-proBNP and hs-cTnT in patients with severe features of preeclampsia

BACKGROUND

Preeclampsia with severe features (SPE) is a multisystem syndrome associated with long-term cardiovascular morbidity. Serum concentrations of N-terminal B-type natriuretic peptide (NT-proBNP) and high sensitivity cardiac troponin-T (hs-cTnT) are sensitive markers of cardiac stretch and ischemia, respectively.

OBJECTIVE

Our aim was to examine NT-proBNP and hs-cTnT in patients with SPE during labor. We hypothesized that patients with severe preeclampsia would have increased serum concentrations of these analytes as compared with normotensive laboring patients.

STUDY DESIGN

This was a prospective cohort study of intrapartum patients with SPE and normotensive controls. Patients were recruited at the time of SPE diagnosis or admission to the labor unit, and those with medical conditions that could predispose to baseline cardiac dysfunction were excluded. Serum from venous blood was collected for NT-proBNP and hs-cTnT measurement at three time points: 0-2 h, 4 h, and 12 h after admission. A mixed random effects regression model was used to compare analyte levels at each time point and to compare trends over time. The primary outcome was NT-proBNP concentration at each collection time point in patients with severe preeclampsia as compared to normotensive controls. Power analysis yielded a goal sample of 25 patients with a 12 h and at least 1 other sample in each arm. Two-tailed P values less than 0.05 were considered statistically significant. P value adjustment for multiple comparisons was performed.

RESULTS

Of 78 patients analyzed, 36 had severe preeclampsia and 42 were normotensive controls with 25 in each cohort having a 12 h and at least 1 other sample. The NT-proBNP trend was significantly different in the two cohorts (P < 0.001). After adjustment for multiple comparisons, the mean serum concentration of NT-proBNP was elevated in the severe preeclampsia group at 0-2 and 4 h, but not at 12 h. After similar adjustment, detectable serum concentrations of hs-cTnT were more frequent in patients with severe preeclampsia at all three timepoints.

CONCLUSION

Intrapartum serum concentrations of NT-proBNP were elevated nearly twofold in patients with SPE when compared with normotensive controls, with the most pronounced differences found during early labor. Detectable but low serum concentrations of hs-cTnT were more common in women with severe preeclampsia as compared with normotensive controls. These findings suggest cardiac dysfunction with SPE may be present at the time of admission and contribute to features of maternal cardiovascular morbidity and mortality.

Outcomes in patients with chest pain in emergency departments using high-sensitivity versus conventional troponins

Objectives. There is a paucity of data regarding the association between the use of high-sensitivity troponin (hs-cTn) compared with conventional troponin (cTn) and outcomes in chest pain patients in emergency departments (EDs). This study examined the impact of hs-cTnT on prognosis in chest pain patients in EDs. Design. In an observational cohort study, we included chest pain patients visiting the EDs of 14 hospitals in Sweden from 2011 to 2016. The study population was retrieved from each hospital, and information on characteristics and outcomes was collected from nationwide registries. Cox regression was used to estimate adjusted hazard ratios with 95% confidence intervals (HR, 95% CI) for (1) 1-year all-cause mortality, (2) missed acute coronary syndromes (ACSs), (3) use of coronary angiography, and (4) revascularizations within 30 days. Results. We included 170461 patients with chest pain where 62669 patients were tested with cTn while 107792 patients were tested with hs-cTnT. We found 4149 (4.6%) deaths in the cTn group and 6087 (3.7%) deaths in the hs-cTnT group. Patients in the hs-cTnT group had 9% lower mortality (0.91, 0.87-0.94), and were 14% more likely to undergo coronary angiography (1.14, 1.10-1.17), and 12% more likely to be revascularized (1.12, 1.08-1.17) than patients in the cTn group. Conclusions. Patients with chest pain visiting EDs using hs-cTnT had lower mortality and a higher likelihood of undergoing coronary angiographies and revascularizations than those using cTn. There may be a survival benefit of being tested with hs-cTnT compared with cTn in patients seeking medical attention for chest pain.

The Relationship Between Cardiac Troponin in People Hospitalised for Exacerbation of COPD and Major Adverse Cardiac Events (MACE) and COPD Readmissions

Background

No single biomarker currently risk stratifies chronic obstructive pulmonary disease (COPD) patients at the time of an exacerbation, though previous studies have suggested that patients with elevated troponin at exacerbation have worse outcomes. This study evaluated the relationship between peak cardiac troponin and subsequent major adverse cardiac events (MACE) including all-cause mortality and COPD hospital readmission, among patients admitted with COPD exacerbation.

Methods

Data from five cross-regional hospitals in England were analysed using the National Institute of Health Research Health Informatics Collaborative (NIHR-HIC) acute coronary syndrome database (2008-2017). People hospitalised with a COPD exacerbation were included, and peak troponin levels were standardised relative to the 99th percentile (upper limit of normal). We used Cox Proportional Hazard models adjusting for age, sex, laboratory results and clinical risk factors, and implemented logarithmic transformation (base-10 logarithm). The primary outcome was risk of MACE within 90 days from peak troponin measurement. Secondary outcome was risk of COPD readmission within 90 days from peak troponin measurement.

Results

There were 2487 patients included. Of these, 377 (15.2%) patients had a MACE event and 203 (8.2%) were readmitted within 90 days from peak troponin measurement. A total of 1107 (44.5%) patients had an elevated troponin level. Of 1107 patients with elevated troponin at exacerbation, 256 (22.8%) had a MACE event and 101 (9.0%) a COPD readmission within 90 days from peak troponin measurement. Patients with troponin above the upper limit of normal had a higher risk of MACE (adjusted HR 2.20, 95% CI 1.75-2.77) and COPD hospital readmission (adjusted HR 1.37, 95% CI 1.02-1.83) when compared with patients without elevated troponin.

Conclusion

An elevated troponin level at the time of COPD exacerbation may be a useful tool for predicting MACE in COPD patients. The relationship between degree of troponin elevation and risk of future events is complex and requires further investigation.

Serum total bilirubin level is associated with contrast induced nephropathy after primary percutaneous coronary intervention

Contrast Induced Nephropathy (CIN) is a major complication of angiographic procedures. Primary percutaneous coronary intervention (pPCI) is the preferred treatment for ST-segment elevation myocardial infarction (STEMI) but is associated with a risk of CIN. Oxidative stress and free radical damage play a role in the pathogenesis of CIN. Bilirubin has anti-inflammatory and antioxidant activity and has been shown to have a protective effect on endothelial cells. The present study aimed to assess the association between serum bilirubin level and development of CIN after pPCI. Sequential STEMI patients (n = 595) who underwent pPCI between January 2021 and December 2022 were enrolled. Among the participants, 116 (19.5%) developed CIN. Serum total bilirubin level was significantly lower in the CIN group (P = .001). In multivariate logistic regression analysis, serum bilirubin level was found as an independent predictor of CIN. Age, gender, contrast volume, and white blood cell count were other independent predictors of CIN. A higher serum bilirubin level is associated with a lower risk of CIN in the present study. In STEMI patients undergoing pPCI, serum bilirubin level may be helpful to predict the risk of CIN and may help ensure early initiation of preventive treatment and careful follow-up.

Use of the HEAR Score for 30-Day Risk-Stratification in Emergency Department Patients

BACKGROUND

The 2021 American College of Cardiology/American Heart Association chest pain guidelines recommend risk scores such as HEAR (History, Electrocardiogram, Age, Risk factors) for short-term risk stratification, yet limited data exist integrating them with high-sensitivity cardiac troponin T (hs-cTnT).

METHODS

Retrospective, multicenter (n = 2), observational, US cohort study of consecutive emergency department patients without ST-elevation myocardial infarction who had at least one hs-cTnT (limit of quantitation [LoQ] <6 ng/L, and sex-specific 99th percentiles of 10 ng/L for women and 15 ng/L for men) measurement on clinical indications in whom HEAR scores (0-8) were calculated. The composite major adverse cardiovascular event (MACE) outcome was 30-day prognosis.

RESULTS

Among 1979 emergency department patients undergoing hs-cTnT measurement, 1045 (53%) were low risk (0-3), 914 (46%) intermediate risk (4-6), and 20 (1%) high risk (7-8) based on HEAR scores. HEAR scores were not associated with increased risk of 30-day MACE in adjusted analyses. Patients with quantifiable hs-cTnT (LoQ-99th) had an increased risk for 30-day MACE (3.4%) irrespective of HEAR scores. Those with serial hs-cTnT <99th percentile remained at low risk (range 0%-1.2%) across all HEAR score strata. Higher scores were not associated with long-term (2-year) events.

CONCLUSIONS

HEAR scores are of limited value in those with baseline hs-cTnT 99th percentile to define short-term prognosis. In those with baseline quantifiable hs-cTnT within the reference range (<99th percentile), a higher risk (>1%) for 30-day MACE exists even in those with low HEAR scores. With serial hs-cTnT measurements, HEAR scores overestimate risk when hs-cTnT remains <99th percentile.

Antibody-mediated interferences affecting cardiac troponin assays: recommendations from the IFCC Committee on Clinical Applications of Cardiac Biomarkers

The International Federation of Clinical Chemistry Committee on Clinical Applications of Cardiac Biomarkers (IFCC C-CB) provides educational documents to facilitate the interpretation and use of cardiac biomarkers in clinical laboratories and practice. Our aim is to improve the understanding of certain key analytical and clinical aspects of cardiac biomarkers and how these may interplay. Measurements of cardiac troponin (cTn) have a prominent place in the clinical work-up of patients with suspected acute coronary syndrome. It is therefore important that clinical laboratories know how to recognize and assess analytical issues. Two emerging analytical issues resulting in falsely high cTn concentrations, often several fold higher than the upper reference limit (URL), are antibody-mediated assay interference due to long-lived cTn-antibody complexes, called macrotroponin, and crosslinking antibodies that are frequently referred to as heterophilic antibodies. We provide an overview of antibody-mediated cTn assay interference and provide recommendations on how to confirm the interference and interpret the results.

Type 2 Myocardial Infarction and Long-Term Mortality Risk Factors: A Retrospective Cohort Study

INTRODUCTION

In-hospital risk factors for type 1 myocardial infarction (MI) have been extensively investigated, but risk factors for type 2 MI are still emerging. Moreover, type 2 MI remains an underdiagnosed and under-researched condition. Our aim was to assess survival rates after type 2 MI and to analyze the risk factors for patient prognosis after hospitalization.

METHODS

We conducted a retrospective database analysis of patients with MI diagnosis who were treated in Vilnius University Hospital Santaros Klinikos. A total of 6495 patients with the diagnosis of MI were screened. The primary study endpoint was long-term all-cause mortality. The predictive value of laboratory tests was estimated including blood hemoglobin, D dimer, creatinine, brain natriuretic peptide (BNP), C-reactive protein (CRP), and troponin levels.

RESULTS

Out of all the patients diagnosed with MI there were 129 cases of type 2 MI (1.98%). Death rate almost doubled from 19.4% at 6 months to 36.4% after 2 years of follow-up. Higher age and impaired kidney function were risk factors for death both during hospitalization and after 2 years of follow-up. Lower hemoglobin (116.6 vs. 98.9 g/L), higher creatinine (90 vs. 161.9 μmol/L), higher CRP (31.4 vs. 63.3 mg/l), BNP (707.9 vs. 2999.3 ng/L), and lower left ventricle ejection fraction were all predictors of worse survival after 2 years of follow-up. Preventive medication during hospitalization can decrease the mortality risk: angiotensin-converting enzyme inhibitor (ACEi) (HR 0.485, 95% CI 0.286-0.820) and statins (HR 0.549, 95% CI 0.335-0.900). No significant influence was found for beta blockers (HR 0.662, 95% CI 0.371-1.181) or aspirin (HR 0.901, 95% CI 0.527-1.539).

CONCLUSIONS

There is significant underdiagnosis of type 2 MI (1.98% out of all MIs). If the patient is prescribed a preventive medication like ACEi or statins, the mortality risk is lower. Increased awareness of elevation of laboratory results could help to improve the treatment of these patients and identify the most vulnerable groups.

Management and outcomes of patients with chest pain and psychiatric disorders in the era of high-sensitivity cardiac troponins

BACKGROUND

The management of patients with psychiatric disease and chest pain in the emergency department (ED) in the era of high-sensitivity cardiac troponin assays is unexplored.

OBJECTIVES

To investigate differences in management and outcomes comparing patients with versus without psychiatric disorders who present with chest pain in the ED.

METHODS

All visits to seven different EDs in Sweden from 9 December 2010 to 31 December 2016 by patients with chest pain were included. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to estimate differences in clinical management. Hazard ratios with 95% CIs were used for comparisons of all-cause mortality and risk of cardiovascular events.

RESULTS

Altogether, 216,653 visits were identified, of which 40,054 (18%) occurred in patients with psychiatric disorders. The risk of a myocardial infarction (MI) was reduced almost by half in patients with an affective (OR 0.63; 95% CI: 0.59-0.68) or psychotic disorder (OR 0.57; 95% CI: 0.47-0.70). These patients were less likely to be treated with any cardiovascular medication or to undergo percutaneous coronary intervention. Contrastingly, patients with psychiatric disease had a 1.8- to 2.6-fold increased risk of being diagnosed with an MI registered after the index visit but within 30 days.

CONCLUSIONS

Patients with psychiatric disease and chest pain undergo less intense investigation and are less likely to receive cardiovascular medications compared with patients without psychiatric disease, even in the presence of myocardial injury. In addition, they experience a higher risk of being diagnosed with an MI within 30 days after a visit with no MI.

Methods for analyzing positive cardiac troponin assay interference

OBJECTIVES

The cardiac damage biomarkers cardiac troponin T (cTnT) and troponin I (cTnI) are used to identify patients with myocardial infarction (MI). To make the correct clinical decisions it is important to identify false positive results due to troponin assay interference. Often interferences are caused by high-molecular weight immunocomplexes called macrotroponin that may result in false troponin elevations because of delayed troponin clearance, or heterophilic antibodies that crosslink troponin assay antibodies and generate troponin-independent signals.

DESIGN & METHODS

We describe and compare four methods for cTnI assay interference analysis using a protein G spin column method, gel filtration chromatography and two versions of a sucrose gradient ultracentrifugation for cTnI assay interference analysis on five patients with confirmed cTnI interference and one MI patient without cTnI interference from our troponin interference referral center.

RESULTS

The protein G spin column method had a high between run variability but was still able to identify all five patients with cTnI interference. The sucrose gradient ultracentrifugation methods and the gel filtration method had simlar performancec and correctly identified the immunocomplexes that caused the cTnI interference.

CONCLUSIONS

Our experience is that these methods are sufficient to safely confirm or exclude positive cTnI assay interference.

Utility of cardiovascular magnetic resonance in patients with stable troponin elevation

AIMS

Cardiovascular magnetic resonance (CMR) imaging has a potential role in the evaluation of symptomatic patients with stable troponin elevation; however, its utility remains unexplored. We sought to determine the incremental diagnostic value of CMR in this unique cohort and assess the long-term clinical outcomes.

METHODS AND RESULTS

Two hundred twenty-five consecutive patients presenting with cardiac chest pain/dyspnoea, stable troponin elevation, and undergoing CMR assessment were identified retrospectively from registry database. The study cohort was prospectively followed for major adverse cardiac events (MACEs) (defined as composite of all-cause mortality and cardiovascular readmissions). The primary outcome measure was the diagnostic utility of CMR, i.e. percentage of patients for whom CMR identified the cause of stable troponin elevation. Secondary outcome measures included the incremental value of CMR and occurrence of MACE. CMR was able to identify the cause for stable troponin elevation in 160 (71%) patients. A normal CMR was identified in 17% and an inconclusive CMR in 12% of the patients. CMR changed the referral diagnosis in 59 (26%) patients. Utilizing a baseline prediction model (pre-CMR referral diagnosis), the net reclassification index was 0.11 and integrated discriminatory improvement index measured 0.33 following CMR. Over a median follow-up of 4.3 years (interquartile range 2.8-6.3), 72 (32%) patients experienced MACE.

CONCLUSION

CMR identified a cause for stable troponin elevation in 7 of 10 cases, and a new diagnosis was evident in 1 of 4 cases. CMR improved the net reclassification of patients with stable troponin elevation.

Cardiac Troponins for the Clinical Management of Patients with Claudication and without Cardiac Symptoms

Many patients with peripheral arterial disease (PAD) exhibit undiagnosed obstructive coronary artery disease. We aim to identify the patients with lifestyle limiting claudication due to PAD and without cardiac symptoms, requiring coronary revascularization based on high-sensitive troponin T (hsTnT) values. We assessed hsTnT in consecutive patients referred for elective endovascular treatment due to claudication [Rutherford categories (RC) 2 & 3] between January 2018 and December 2021. Diagnostic work-up by non-invasive imaging and, if required, cardiac catheterization was performed according to clinical data, ECG findings and baseline hsTnT. The occurrence of cardiac death, myocardial infarction or urgent revascularization during follow-up was the primary endpoint. Of 346 patients, 14 (4.0%) exhibited elevated hsTnT ≥ 14 ng/L, including 7 (2.0%) with acute myocardial injury by serial hsTnT sampling. Coronary revascularization by percutaneous coronary intervention was necessary in 6 of 332 (1.5%) patients with normal versus nine of 14 (64.3%) patients with elevated hsTnT (p < 0.001). During 2.4 ± 1.4 years of follow-up, 20 of 286 (7.0%) patients with normal versus four of 13 (30.8%) with elevated hsTnT at baseline reached the composite primary endpoint (p = 0.03 by log-rank test). In conclusion, elevated troponins in cardiac asymptomatic patients with claudication modify subsequent cardiac management and may increase the need for closer surveillance and more aggressive conservative management in polyvascular disease.

Clinical implications of cardiac troponin-I in patients with hypertensive crisis visiting the emergency department

OBJECTIVES

Cardiac troponin-I (cTnI) is a representative marker of myocardial injury. Elevation of cTnI is frequently observed in patients with hypertensive crisis, but few studies have examined its prognostic significance in hypertensive crisis. We aimed to determine whether cTnI could predict all-cause mortality in patients with hypertensive crisis visiting the emergency department (ED).

METHODS

This observational study included patients aged ≥18 years who visited an ED between 2016 and 2019 for hypertensive crisis, defined as systolic blood pressure (BP) ≥180 mmHg and/or diastolic BP ≥110 mmHg. Among 6467 patients, 3938 who underwent a cTnI assay were analysed.

RESULTS

Among the 3938 patients, 596 (15.1%) had cTnI levels above the 99th percentile upper reference limit (elevated cTnI >40 ng/L) and 600 (15.2%) had cTnI levels between the detection limit (≥10 ng/L) and the 99th percentile upper reference limit (detectable cTnI). The 3-year all-cause mortality in the elevated, detectable and undetectable cTnI groups were 41.6%, 36.5% and 12.8%, respectively. After adjusting for confounding variables, elevated cTnI patients (adjusted hazard ratio [HR], 2.01; 95% confidence interval [CI], 1.61-2.52) and detectable cTnI patients (adjusted HR, 1.64; 95% CI, 1.32-2.04) showed a significantly higher risk of 3-year all-cause mortality than did patients with undetectable cTnI.

CONCLUSIONS

In patients with hypertensive crisis, elevated cTnI levels provide useful prognostic information and permit the early identification of patients with an increased risk of death. Moreover, putatively normal but detectable cTnI levels also significantly correlated with a higher risk of all-cause mortality. Intensive treatment and follow-up strategies are needed for patients with hypertensive crisis with elevated and detectable cTnI levels.Key messagesCardiac troponin-I level was an independent prognostic factor for all-cause mortality in patients with hypertensive crisis.Detectable but normal range cardiac troponin-I, which was considered clinically insignificant, also had a prognostic impact on all-cause mortality comparable to elevated cardiac troponin-I levels.

Advantage of Using of High-Sensitivity Troponin I Compared to Conventional Troponin I in Shortening Time to Rule out/in Acute Coronary Syndrome in Chest Pain Patients Presenting to the Emergency Department

Background and Objectives: We aimed to compare the time to diagnosis for acute coronary syndromes using high-sensitivity troponin I (hsTnI) and conventional troponin I (TnI) in patients presenting to the emergency department (ED) with chest pain. Materials and Methods: This was an observational prospective study involving patients presenting to the ED of Sant’Andrea Hospital University la Sapienza in Rome (Italy) with chest pain from January to December 2014. Serum troponin was drawn at presentation, and at 3, 6, 9, and/or 12 h if clinically indicated. Depending on date of recruitment, patients had either hsTnI (Abbott Laboratories) or TnI (Abbott Laboratories) performed. The primary endpoint was the time to diagnosis at index visit. Results: A total of 1059 patients were recruited, (673 [63.6%] male, median age 60 years [interquartile range 49−73 years]), out of whom 898 (84.8%) patients were evaluated with hsTnI and 161 (15.2%) with TnI. A total of 393 (37.1%) patients had the diagnosis of acute coronary syndrome in ED. The median time to diagnosis for those evaluated with TnI was 400 min, IQR 120−720 min, while the use of hsTnI led to a significantly shorter time to diagnosis (median 200 min, IQR 100−200 min, p < 0.001). Conclusions: This study confirms that in patients presenting to the emergency department with chest pain, the use of hsTnI is associated with a reduced time to ruling in/out ACS, and, consequently, hsTnI should be routinely used over TnI for more rapid identification of ACS with benefits for patients and related costs.

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.

Temporal Changes of Stable High-Sensitivity Cardiac Troponin T Levels and Prognosis

Background The prognostic implications of temporal change of previously stable high-sensitivity cardiac troponin concentrations are unknown. We investigated the prognosis associated with temporal changes of stable high-sensitivity cardiac troponin T (hs-cTnT) concentrations. Methods and Results All patients presenting with cardiac symptoms and ≥2 hs-cTnT measurements at the time of their first visit to 7 different emergency departments in Sweden between December 9, 2009, and December 31, 2016, were identified (n=66 159). We included all patients with stable hs-cTnT but no acute coronary syndrome diagnosis who had ≥1 hs-cTnT measured also at a second visit >30 days from the first visit. Hazard ratios (HRs) with 95% CIs were calculated for all-cause mortality and cardiovascular events according to temporal change of hs-cTnT between the visits, using patients without myocardial injury (<15 ng/L) at the first visit and persistently stable hs-cTnT at the second visit as the reference. Altogether, 12 869 patients were included, of whom 5191 (40%) had myocardial injury (hs-cTnT ≥15 ng/L). During a median follow-up of 2.3 (interquartile range, 1.4-3.7) years, 3271 (25%) patients died. In patients with myocardial injury and a temporal increase in hs-cTnT, the adjusted all-cause and cardiovascular mortality was 4- and 5-fold elevated (HR, 4.21; 95% CI, 3.55-5.00; and HR, 5.08; 95% CI, 3.73-6.92), and the adjusted risk of heart failure hospitalization almost 3-fold (HR, 2.77; 95% CI, 2.26-3.39). Conclusions Temporal change of previously stable hs-cTnT is associated with the risk of death and cardiovascular outcomes, with highest risks observed in patients with myocardial injury and increasing hs-cTnT.

Cardiovascular Biomarkers: Lessons of the Past and Prospects for the Future

Cardiovascular diseases (CVDs) are a major healthcare burden on the population worldwide. Early detection of this disease is important in prevention and treatment to minimise morbidity and mortality. Biomarkers are a critical tool to either diagnose, screen, or provide prognostic information for pathological conditions. This review discusses the historical cardiac biomarkers used to detect these conditions, discussing their application and their limitations. Identification of new biomarkers have since replaced these and are now in use in routine clinical practice, but still do not detect all disease. Future cardiac biomarkers are showing promise in early studies, but further studies are required to show their value in improving detection of CVD above the current biomarkers. Additionally, the analytical platforms that would allow them to be adopted in healthcare are yet to be established. There is also the need to identify whether these biomarkers can be used for diagnostic, prognostic, or screening purposes, which will impact their implementation in routine clinical practice.

Unstable Angina Pectoris With Myocardial Injury Versus Myocardial Infarction in the Era of High-Sensitivity Cardiac Troponin

It is unknown whether outcomes in patients with unstable angina pectoris (UAP) and myocardial injury are different from outcomes in patients with non-ST-segment myocardial infarction (NSTEMI) with low peak concentrations of high-sensitivity cardiac troponin T (hs-cTnT). This study aimed to compare the prognosis in patients with UAP and evidence of myocardial injury, with prognosis in patients with NSTEMI and different peak hs-cTnT concentrations. All visits to 7 different emergency departments in Sweden from December 9, 2009 to December 31, 2016 were identified (n = 5,225,075). We included all hospitalized patients with hs-cTnT >14 ng/L and a diagnosis of UAP or NSTEMI, with ≥2 hours-cTnT measurements. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated for all-cause mortality and cardiovascular events, in patients with NSTEMI categorized according to peak hs-cTnT concentrations, compared with patients with UAP. Altogether, 11,944 patients were included, of whom 1,253 (10%) received a diagnosis of UAP. During a median follow-up of 3.0 years (interquartile [IQR] 1.6 to 4.7), 3,297 patients died. There was no difference comparing patients with NSTEMI with peak hs-cTnT of 15 to 49 ng/L to patients with UAP, with regards to long-term cardiovascular mortality (HR 1.15; 95% CI, 0.85 to 1.56), but the risk of recurrent myocardial infarction was higher in patients with NSTEMI (HR, 1.61; 95% CI, 1.29 to 2.00), and the risk of heart failure hospitalization slightly lower (HR 0.80, 95% CI, 0.64 to 0.99). In conclusion, patients with UAP and myocardial injury have a similar risk of death after discharge, but a lower risk of recurrent myocardial infarction and a marginally higher risk of heart failure, compared with patients with NSTEMI with moderately elevated hs-cTnT levels.

The ratio of cardiac troponin T to troponin I may indicate non-necrotic troponin release among COVID-19 patients

BACKGROUND

Although cardiac troponin T (cTnT) and troponin I(cTnI) are expressed to similar amount in cardiac tissue, cTnI often reach ten-times higher peak levels compared to cTnT in patients with myocardial necrosis such as in acute myocardial infarction (MI). In contrast, similar levels of cTnT and cTnI are observed in other situations such as stable atrial fibrillation and after strenuous exercise.

OBJECTIVE

Examine cTnT and cTnI levels in relation to COVID-19 disease and MI.

METHODS

Clinical and laboratory data from the local hospital from an observational cohort study of 27 patients admitted with COVID-19 and 15 patients with myocardial infarction (MI) that were analyzed with paired cTnT and cTnI measurement during hospital care.

RESULTS

Levels of cTnI were lower than cTnT in COVID-19 patients (TnI/TnT ratio 0.3, IQR: 0.1-0.6). In contrast, levels of cTnI were 11 times higher compared to cTnT in 15 patients with MI (TnI/TnT ratio 11, IQR: 7-14). The peak cTnI/cTnT ratio among the patients with MI following successful percutaneous intervention were 14 (TnI/TnT ratio 14, IQR: 12-23). The 5 COVID-19 patient samples collected under possible necrotic events had a cTnI/cTnT ratio of 5,5 (IQR: 1,9-8,3).

CONCLUSIONS

In patients with COVID-19, cTnT is often elevated to higher levels than cTnI in sharp contrast to patients with MI, indicating that the release of cardiac troponin has a different cause in COVID-19 patients.

Effect of Revascularization on Exercise-Induced Changes in Cardiac and Prothrombotic Biomarkers in Patients with Coronary Artery Disease

We examined whether resting levels and exercise-induced changes during exercise ECG stress test (EST) of cardiac Troponin T (cTnT), NT-proBNP and prothrombotic markers were affected by revascularization in patients with coronary artery disease (CAD).

EST1 was performed before coronary angiography and revascularization, and patients (n  =  20) with confirmed CAD, performed another EST (EST2) 9 weeks later. Blood samples were drawn at rest and within five min after termination of ESTs.

cTnT and NT-proBNP increased during exercise at both ESTs (p < 0.001, all). Resting cTnT levels at EST2 versus EST1 were significantly higher (p  =  0.02) whereas NT-proBNP did not differ. At both visits, increased D-dimer (p  =  0.008 and <0.001), pro-thrombin fragment 1  +  2 (p  =  0.009 and 0.001) and tissue factor pathway inhibitor (TFPI) (p < 0.001 and 0.001) during exercise were demonstrated. Resting levels of endogenous thrombin potential (ETP) and TFPI were reduced at EST2 versus EST1 (p < 0.01).

Revascularization did not affect exercise-induced release of cardiac and prothrombotic biomarkers and did not reduce resting levels of cTnT or NT-proBNP, suggesting revascularization per se not to prevent secretion of biomarkers. The lower resting levels of ETP and TFPI after revascularization may however, be indicative of reduced thrombin generation and endothelial activation.

Clinicaltrials.gov, CADENCE, NCT01495091 https://clinicaltrials.gov/ct2/show/NCT01495091?term = 01495091&draw = 2&rank = 1.

Exercise-Induced Cardiac Troponin Elevations: From Underlying Mechanisms to Clinical Relevance

Supplemental Digital Content is available in the text.

Serological assessment of cardiac troponins (cTn) is the gold standard to assess myocardial injury in clinical practice. A greater magnitude of acutely or chronically elevated cTn concentrations is associated with lower event-free survival in patients and the general population. Exercise training is known to improve cardiovascular function and promote longevity, but exercise can produce an acute rise in cTn concentrations, which may exceed the upper reference limit in a substantial number of individuals. Whether exercise-induced cTn elevations are attributable to a physiological or pathological response and if they are clinically relevant has been debated for decades. Thus far, exercise-induced cTn elevations have been viewed as the only benign form of cTn elevations. However, recent studies report intriguing findings that shed new light on the underlying mechanisms and clinical relevance of exercise-induced cTn elevations. We will review the biochemical characteristics of cTn assays, key factors determining the magnitude of postexercise cTn concentrations, the release kinetics, underlying mechanisms causing and contributing to exercise-induced cTn release, and the clinical relevance of exercise-induced cTn elevations. We will also explain the association with cardiac function, correlates with (subclinical) cardiovascular diseases and exercise-induced cTn elevations predictive value for future cardiovascular events. Last, we will provide recommendations for interpretation of these findings and provide direction for future research in this field.

Statin Therapy and Intensity: Prognosis in Patients with Myocardial Injury

BACKGROUND

No guideline-directed pharmacological therapy has been established for patients with myocardial injury without type 1 myocardial infarction. We investigated the impact of statin treatment in patients with myocardial injury.

METHODS

Patients with myocardial injury (nonischemic acute and chronic myocardial injury), type 2 myocardial infarction, and type 1 myocardial infarction with at least 1 emergency department visit for chest pain from 2011 to 2014 were included. Dispensed prescriptions of all types of statins with dosage within 180 days from the index visit were collected. In total, 2054 patients were divided into 3 groups: 1) acute myocardial injury (type 2 myocardial infarction, acute nonischemic myocardial injury), 2) chronic myocardial injury, and 3) type 1 myocardial infarction. We estimated the adjusted hazard ratio with 95% confidence interval for death with low- (reference), moderate-, and high-intensity statin therapy.

RESULTS

The mean follow-up was 4.2 ± 1.8 years. Only 13% of patients with acute and chronic myocardial injury and 30% with type 1 myocardial infarction were treated with high-intensity statins. Adjusted mortality rates were higher in patients with acute and chronic myocardial injury than in those with type 1 myocardial infarction across all statin intensity categories. In patients with type 1 myocardial infarction, the adjusted mortality risk was 20% (hazard ratio, 0.80; 95% confidence interval, 0.36-1.77) lower in patients with high-intensity therapy. Point estimates in the adjusted models indicated similar associations between statin intensity and mortality risk in patients with acute and chronic myocardial injury.

CONCLUSION

Patients with myocardial injury may benefit from high-intensity statin treatment, but the associations were not statistically significant when adjusting for confounders.

Stable high-sensitivity cardiac troponin T levels and the association with frailty and prognosis in patients with chest pain

Background

Chronic myocardial injury is defined by stable high-sensitivity cardiac troponin (hs-cTn) levels above the 99th percentile value, which may be a sign of a biologically aged heart. This study investigated the association between frailty and chronic myocardial injury.

Methods

In a cohort of patients with chest pain and stable hs-cTnT levels measured 2011-2014, we included all patients who were assessed by two scoring systems measuring frailty. Adjusted odds ratios (ORs) were calculated to estimate the risk of frailty at different hs-cTnT levels (referent: hs-cTnT ≤ 14 ng/l). Cox regression was used to estimate risks of death and cardiovascular events in relation to frailty status and hs-cTnT levels (referent: non-frail and hs-cTnT ≤ 14 ng/l).

Results

A total of 979 patients were included, of whom 269 (27%) had chronic myocardial injury. The risk of being frail was almost four times higher in patients with chronic myocardial injury, compared with patients in the reference group (hs-cTnT ≥ 30 ng/l: OR: 3.69, 95% CI: 2.02-6.76). During a follow-up of 4.3 years, 275 (28%) patients died. Mortality risks increased with increasing hs-cTnT levels and degree of frailty, being increased four-fold in frail patients with hs-cTnT levels ≥ 30 ng/l (HR: 4.07, 95% CI: 2.42-6.86).

Conclusions

Stable hs-cTnT levels are associated with the degree of frailty, and frailty measurements could help to identify patients with stable hs-cTnT levels who are at a high risk of death. The findings support the hypothesis that chronic myocardial injury could be a marker of a biologically aged heart.

Advances in point-of-care testing for cardiovascular diseases

Point-of-care testing (POCT) is a specific format of diagnostic testing that is conducted without accompanying infrastructure or sophisticated instrumentation. Traditionally, such rapid sample-to-answer assays provide inferior analytical performances to their laboratory counterparts when measuring cardiac biomarkers. Hence, their potentially broad applicability is somewhat bound by their inability to detect clinically relevant concentrations of cardiac troponin (cTn) in the early stages of myocardial injury. However, the continuous refinement of biorecognition elements, the optimization of detection techniques, and the fabrication of tailored fluid handling systems to manage the sensing process has stimulated the production of commercial assays that can support accelerated diagnostic pathways. This review will present the latest commercial POC assays and examine their impact on clinical decision-making. The individual elements that constitute POC assays will be explored, with an emphasis on aspects that contribute to economically feasible and highly sensitive assays. Furthermore, the prospect of POCT imparting a greater influence on early interventions for medium to high-risk individuals and the potential to re-shape the paradigm of cardiovascular risk assessments will be discussed.

Cardiac troponin I and the risk of cardiovascular or non-cardiovascular death in patients visiting the emergency department

The prognostic implication of cardiac troponin I (cTnI) values for the determination of the magnitude or duration of cause-specific death risk is limited. We included consecutive patients with maximal cTnI values within 24 h of their emergency department visits. Multivariate analyses using variables selected by the Bayesian information criterion were performed to investigate the impact of cTnI on the event rate, time-dependent risk, and dose-dependent risk of cardiovascular or non-cardiovascular death within 360 days. There were 5472 (14.9%) all-cause deaths including 881 (2.4%) cardiovascular deaths and 4591 (12.5%) non-cardiovascular deaths. In patients with positive cTnI, defined as the ≥ 99th percentile of the upper normal limit, the cumulative risk of cardiac and non-cardiac death was 4.4- and 1.4-fold higher, respectively, than that of negative cTnI, respectively. In the competing risk analysis, positive cTnI was linked to 2.4- and 1.2-fold higher risks of cardiovascular and non-cardiovascular death, respectively. The cTnI value showed a positive relationship with the risk of both cardiovascular and non-cardiovascular deaths. In the time-dependent risk analysis, the excess risk of cardiovascular death was mostly evident in the first few weeks. Higher cTnI value was associated with an increased risk of both cardiovascular and non-cardiovascular death, especially which was in the early period.

Prognostic Implications of High-Sensitivity Troponin T Levels Among Patients Attending Emergency Departments and Evaluated for an Acute Coronary Syndrome

BACKGROUND

With increasing age, patients with suspected acute coronary syndromes (ACS) and elevated high-sensitivity troponin T (HsTnT) levels, type-1 myocardial infarction (MI) is diagnosed less often, though associations among these factors, gender, and prognosis is unclear.

METHODS

Patients presenting to the emergency department (ED) with potential ACS who underwent HsTnT testing were prospectively identified and followed. Diagnoses were adjudicated according to the Fourth Universal Definition of MI as follows: type-1 MI, type-2 MI, acute myocardial injury, chronic myocardial injury, and other diagnoses. Age in years was categorized: younger (<65); elderly (65-79), and very elderly (≥80).

RESULTS

Among 2738 patients with HsTnT measurements, 1611 were suitable for adjudication (42% ages 65 years and younger). Type-2 MI and chronic myocardial injury diagnoses were more common in those ages 65 years and older, whereas younger patients had more type-1 MI diagnoses. Late mortality rates at median 41 months (interquartile range [IQR] 10-57) were 44% (223 out of 506) in those ages 80 years and older, 22% (92 out of 423) in patients 65-79 years, and 7% (46 out of 682) in those 65 years and younger, irrespective of adjudicated diagnoses, log rank P ≤ .001. On multivariable analyses, the adjusted mortality hazard ratios for increasing HsTnT levels irrespective of diagnoses were attenuated in those age 80 years and older compared to younger patients.

CONCLUSIONS

Patients ages 65 years and older constituted ~60% of ED attendances of patients with suspected ACS, and more had type 2 MI and chronic myocardial injury diagnoses compared to younger patients. The relative mortality impact of HsTnT levels was lower among elderly patients irrespective of adjudicated diagnoses.

Novel Immune Cell Subsets Exhibit Different Associations With Vascular Outcomes in Chronic Kidney Disease Patients-Identifying Potential Biomarkers

Background and Aims: Alterations in novel immune cell subsets, such as angiogenic T cells (Tang), senescent T cells (CD4⁺CD28^null), and monocyte subsets are associated with impaired vascular homeostasis in several inflammatory conditions. However, mediators underlying vascular deterioration in chronic kidney disease (CKD) are poorly characterized. This study assessed their role in the vascular deterioration of CKD using a broad spectrum of surrogate markers ranging from altered functionality to overt calcification.

Methods: Tang (CD3⁺CD31⁺CXCR4⁺), CD4⁺CD28^null cells, and monocytes [CD14/CD16 subsets and angiotensin-converting enzyme (ACE) expression] were measured in peripheral blood by flow cytometry in 33 CKD stage 5 patients undergoing peritoneal dialysis (CKD5-PD) and 15 healthy controls (HCs). Analyses were replicated in a hemodialysis cohort. Vascular surrogate markers (including adventitial vasa vasorum, pulse wave velocity, intima-media thickness, and vascular calcification) were assessed by appropriate imaging methods.

Results: In CKD5-PD, decreased Tang levels (p < 0.001) were unrelated to clinical features or traditional cardiovascular (CV) risk factors but correlated negatively with troponin T levels (r = −0.550, p = 0.003). Instead, CD4⁺CD28^null frequency was increased (p < 0.001), especially in those with vascular calcifications. Quantitative and qualitative differences were also observed within the monocyte pool, a shift toward CD16⁺ subsets and ACE expression being found in CKD. Equivalent results were observed in the replication cohort. Each subset associated distinctly with adverse vascular outcomes in univariate and multivariate analyses: while Tang depletion was linked to poor vascular function and subclinical atherosclerosis, increases in CD4⁺CD28^null were associated with overt vascular thickening and calcification. Monocytes were not independently associated with vascular outcomes in CKD patients.

Conclusions: Novel T cell and monocyte subsets are altered in CKD. Altered T-cell subpopulations, but not monocytes, exhibited distinct associations with different vascular outcomes in CKD. Tang are emerging biomarkers of subclinical vascular deterioration in CKD.

Use of historical high-sensitivity cardiac troponin T levels to rule out myocardial infarction

Objective

Several high-sensitivity cardiac troponin (hs-cTn)-based strategies exist for rule-out of myocardial infarction (MI). It is unknown whether historical hs-cTnT concentrations can be used. This study aim to evaluate the performance of a rule-out strategy based on the European Society of Cardiology (ESC) 0/1-hour algorithm, using historical hs-cTnT concentrations.

Methods

All visits among patients with chest pain in the emergency department at nine different hospitals in Sweden from 2012 to 2016 were eligible (221 490 visits). We enrolled patients with a 0-hour hs-cTnT of <12 ng/L, a second hs-cTnT measured within 3.5 hours, and ≥1 historical hs-cTnT available. We calculated the risks of MI and all-cause mortality using two rule-out strategies: (1) a delta hs-cTnT of <3 ng/L between the 0-hour hs-cTnT and the second hs-cTnT (modified ESC algorithm) and (2) a historical hs-cTnT <12 ng/L and a delta hs-cTnT of <3 ng/L in relation to the 0-hour hs-cTnT (historical-hs-cTnT algorithm).

Results

A total of 8432 patients were included, of whom 84 (1.0%) had an MI. The modified ESC algorithm triaged 8100 (96%) patients toward ruled-out, for whom 30-day MI risk and negative predictive value (NPV) for MI (95% CI) were 0.4% (0.3% to 0.6%) and 99.6% (99.4% to 99.7%), respectively. The historical-hs-cTnT algorithm ruled out 6700 (80%) patients, with a 30-day MI risk of 0.5% (0.4% to 0.8%) and NPV of 99.5% (99.2% to 99.6%).

Conclusions

The application of algorithm resulted in similar MI risk and NPV to an established algorithm. The usefulness of historical hs-cTnT concentrations should merit further attention.

Patients discharged with elevated baseline high-sensitive cardiac troponin T from the emergency department

BACKGROUND

Elevated levels of high-sensitive cardiac troponin T (hs-cTnT) are linked to poor prognosis among emergency department (ED) patients.

OBJECTIVE

Examine the effect of our ED risk assessment among patients with suspected acute coronary syndrome (ACS) and elevated baseline hs-cTnT levels.

DESIGN

Observational cohort study of 16776 ED patients with chest pain or dyspnoea and a hs-cTnT sample analyzed at the time of the ED visit. Of these 1480 patients were sent home with elevated hs-cTnT levels (>14 ng/L).

METHODS

Analysis of clinical and laboratory data from the local hospital and data from the National Board of Health and Welfare.

RESULTS

Admitted patients had 11% and discharged patients had 1.2% 90-day mortality indicating effective risk assessment of patients with suspected ACS. However, if the suspected ACS patient presented with hs-cTnT between 14 and 22 ng/L, the 90-day mortality was 4.1% among discharged and 6.7% among admitted patients. Among discharged patients, an hs-cTnT level above 14 ng/L was a higher independent risk factor for 90-day mortality (HR 3.3, 95% CI 2.9-3.7, p < 0.001) than if the patient was triaged as a high-risk patient (HR 1.6, 95% CI 1.1-1.8, p < 0.001).

CONCLUSIONS

Our ED risk assessment was less effective among patients presenting with elevated hs-cTnT levels.

Type-II myocardial infarction and chronic myocardial injury rates, invasive management, and 4-year mortality among consecutive patients undergoing high-sensitivity troponin T testing in the emergency department

AIMS

As assessment of patients with suspected acute coronary syndromes (ACS) in emergency departments (EDs) represents a major workload because high-sensitivity troponin (HsTn) T and I levels are frequently measured, and a minority of patients have final diagnosis of myocardial infarction (MI). We determined the relative frequencies of three patients groups: Type-I MI, Type-II MI (including acute myocardial injury).

METHODS AND RESULTS

Among 2738 consecutive patients with suspected ACS presenting to ED at Liverpool Hospital, Australia, between March and June 2014. We studied the use of invasive and pharmacological therapies, and 4-year outcomes. Adjudication of MI was according to the 4th universal definition as follows: (i) Type-I MI; (ii) Type-II MI (including acute myocardial injury), and (iii) chronic myocardial injury. Of 995 patients (36%) [median age 76 years (interquartile range 65-83)] with ≥2 HsTnT measurements and one >14 ng/L, 727 (73%) had chronic myocardial injury, 171 (17%) had Type-II MI, and 97 (9.7%) had Type-I MI; respective late mortality rates to 48 months were 33%, 43%, and 14% (P < 0.001). In-hospital angiography rates were 95% for patients with Type-I MI, [62% had percutaneous coronary intervention (PCI)] 24% (7% PCI) for those with Type-II MI, and 3.4% for chronic myocardial injury. On Cox modelling for mortality relative to Type 1 MI, adjusted hazard ratios were 1.94 [95% confidence intervals (CIs) 1.06-3.57]; P = 0.032 for Type 2 MI, and for chronic myocardial injury 1.14 (95% CIs 0.64-2.02); P = 0.66.

CONCLUSION

Among unselected patients undergoing HsTnT testing in EDs, Type-II MI including acute myocardial injury was more common than Type-I MI. Chronic myocardial injury, which occurred in three of four patients. Whereas patients with Type-II MI had higher late mortality than those with Type-I MI, after multivariable analyses mortality rates were marginally different.

Prospective Validation and Comparative Analysis of Coronary Risk Stratification Strategies Among Emergency Department Patients With Chest Pain

Background

Coronary risk stratification is recommended for emergency department patients with chest pain. Many protocols are designed as “rule‐out” binary classification strategies, while others use graded‐risk stratification. The comparative performance of competing approaches at varying levels of risk tolerance has not been widely reported.

Methods and Results

This is a prospective cohort study of adult patients with chest pain presenting between January 2018 and December 2019 to 13 medical center emergency departments within an integrated healthcare delivery system. Using an electronic clinical decision support interface, we externally validated and assessed the net benefit (at varying risk thresholds) of several coronary risk scores (History, ECG, Age, Risk Factors, and Troponin [HEART] score, HEART pathway, Emergency Department Assessment of Chest Pain Score Accelerated Diagnostic Protocol), troponin‐only strategies (fourth‐generation assay), unstructured physician gestalt, and a novel risk algorithm (RISTRA‐ACS). The primary outcome was 60‐day major adverse cardiac event defined as myocardial infarction, cardiac arrest, cardiogenic shock, coronary revascularization, or all‐cause mortality. There were 13 192 patient encounters included with a 60‐day major adverse cardiac event incidence of 3.7%. RISTRA‐ACS and HEART pathway had the lowest negative likelihood ratios (0.06, 95% CI, 0.03–0.10 and 0.07, 95% CI, 0.04–0.11, respectively) and the greatest net benefit across a range of low‐risk thresholds. RISTRA‐ACS demonstrated the highest discrimination for 60‐day major adverse cardiac event (area under the receiver operating characteristic curve 0.92, 95% CI, 0.91–0.94, P<0.0001).

Conclusions

RISTRA‐ACS and HEART pathway were the optimal rule‐out approaches, while RISTRA‐ACS was the best‐performing graded‐risk approach. RISTRA‐ACS offers promise as a versatile single approach to emergency department coronary risk stratification.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03286179.

Treatment With Cardiovascular Medications: Prognosis in Patients With Myocardial Injury

Background There is no clinical guidance on treatment in patients with non-ischemic myocardial injury and type 2 myocardial infarction (T2MI). Methods and Results In a cohort of 22 589 patients in the emergency department at Karolinska University Hospital in Sweden during 2011 to 2014 we identified 3853 patients who were categorized into either type 1 myocardial infarction, T2MI, non-ischemic acute and chronic myocardial injury. Data from all dispensed prescriptions within 180 days of the visit to the emergency department were obtained concerning β-blockers, angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers, statins, and platelet inhibitors. We estimated adjusted hazard ratios (HR) with 95% CI for all-cause mortality in relationship to the number of medications (categorized into 0-1 [referent], 2-3 and 4 medications) in the groups of myocardial injury. In patients with T2MI, treatment with 2 to 3 and 4 medications was associated with a 50% and 56% lower mortality, respectively (adjusted HR [95% CI], 0.50 [0.25-1.01], and 0.43 [0.19-0.96]), while corresponding associations in patients with acute myocardial injury were 24% and 29%, respectively (adjusted HR [95% CI], 0.76 [0.59-0.99] and 0.71 [0.5-1.02]), and in patients with chronic myocardial injury 27% and 37%, respectively (adjusted HR [95% CI], 0.73 [0.58-0.92] and 0.63 [0.46-0.87]). Conclusions Patients with T2MI and non-ischemic acute or chronic myocardial injury are infrequently prescribed common cardiovascular medications compared with patients with type 1 myocardial infarction. However, treatment with guideline recommended drugs in patients with T2MI and acute or chronic myocardial injury is associated with a lower risk of death after adjustment for confounders.

Cardiac Troponin Assays With Improved Analytical Quality: A Trade-Off Between Enhanced Diagnostic Performance and Reduced Long-Term Prognostic Value

Background

Cardiac troponin (cTn) permits early rule‐out/rule‐in of patients admitted with possible non–ST‐segment–elevation myocardial infarction. In this study, we developed an admission and a 0/1 hour rule‐out/rule‐in algorithm for a troponin assay with measurable results in >99% of healthy individuals. We then compared its diagnostic and long‐term prognostic properties with other protocols.

Methods and Results

Blood samples were collected at 0, 1, 3, and 8 to 12 hours from patients admitted with possible non–ST‐segment–elevation myocardial infarction. cTnT (Roche Diagnostics), cTnI_(Abbott) (Abbott Diagnostics), and cTnI_(sgx) (Singulex Clarity System) were measured in 971 admission and 465 1‐hour samples. An admission and a 0/1 hour rule‐out/rule‐in algorithm were developed for the cTnI_(sgx) assay and its diagnostic properties were compared with cTnT_ESC (European Society of Cardiology), cTnI_(Abbott)ESC, and 2 earlier cTnI_(sgx) algorithms. The prognostic composite end point was all‐cause mortality and future nonfatal myocardial infarction during a median follow‐up of 723 days. non–ST‐segment–elevation myocardial infarction prevalence was 13%. The novel cTnI_(sgx) algorithms showed similar performance regardless of time from symptom onset, and area under the curve was significantly better than comparators. The cTnI_{(sgx)0/1 hour} algorithm classified 92% of patients to rule‐in or rule‐out compared with ≤78% of comparators. Patients allocated to rule‐out by the prior published 0/1 hour algorithms had significantly fewer long‐term events compared with the rule‐in and observation groups. The novel cTnI_{(sgx)0/1 hour} algorithm used a higher troponin baseline concentration for rule‐out and did not allow for prognostication.

Conclusions

Increasingly sensitive troponin assays may improve identification of non–ST‐segment–elevation myocardial infarction but could rule‐out patients with subclinical chronic myocardial injury. Separate protocols for diagnosis and risk prediction seem appropriate.

Novel clearance of muscle proteins by muscle cells

Blood levels of cardiac troponins (cTn) and myoglobin are analysed when myocardial infarction (MI) is suspected. Here we describe a novel clearance mechanism for muscle proteins by muscle cells. The complete plasma clearance profile of cTn and myoglobin was followed in rats after intravenous or intermuscular injections and analysed by PET and fluorescence microscopy of muscle biopsies and muscle cells. Compared with intravenous injections, only 5 % of cTnT, 0.6 % of cTnI and 8 % of myoglobin were recovered in the circulation following intramuscular injection. In contrast, 47 % of the renal filtration marker FITC-sinistrin and 81 % of cTn fragments from MI-patients were recovered after intramuscular injection. In addition, PET and biopsy analysis revealed that cTn was taken up by the quadriceps muscle and both cTn and myoglobin were endocytosed by cultured muscle cells. This local clearance mechanism could possibly be the dominant clearance mechanism for cTn, myoglobin and other muscle damage biomarkers released by muscle cells.

Diagnostic Reclassification by a High-Sensitivity Cardiac Troponin Assay

STUDY OBJECTIVE

Our objective is to describe the rates of diagnostic reclassification between conventional cardiac troponin I (cTnI) and high-sensitivity cardiac troponin T (hs-cTnT) and between combined and sex-specific hs-cTnT thresholds in adult emergency department (ED) patients in the United States.

METHODS

We conducted a prospective, single-center, before-and-after, observational study of ED patients aged 18 years or older undergoing single or serial cardiac troponin testing in the ED for any reason before and after hs-cTnT implementation. Conventional cTnI and hs-cTnT results were obtained from a laboratory quality assurance database. Combined and sex-specific thresholds were the published 99th percentile upper reference limits for each assay. Cases underwent physician adjudication using the Fourth Universal Definition of Myocardial Infarction. Diagnostic reclassification occurred when a patient received a diagnosis of myocardial infarction or myocardial injury with one assay but not the other assay. Our primary outcome was diagnostic reclassification between the conventional cTnI and hs-cTnT assays. Diagnostic reclassification probabilities were assessed with sample proportions and 95% confidence intervals for binomial data.

RESULTS

We studied 1,016 patients (506 men [50%]; median age 60 years [25th, 75th percentiles 49, 71]). Between the conventional cTnI and hs-cTnT assays, 6 patients (0.6%; 95% confidence interval 0.2% to 1.3%) underwent diagnostic reclassification regarding myocardial infarction (5/6 reclassified as no myocardial infarction) and 166 patients (16%; 95% confidence interval 14% to 19%) underwent diagnostic reclassification regarding myocardial injury (154/166 reclassified as having myocardial injury) by hs-cTnT.

CONCLUSION

Compared with conventional cTnI, the hs-cTnT assay resulted in no clinically relevant change in myocardial infarction diagnoses but substantially more myocardial injury diagnoses.

Myocardial Infarction Can Be Safely Excluded by High-sensitivity Troponin I Testing 3 Hours After Emergency Department Presentation

BACKGROUND

The accuracy and speed by which acute myocardial infarction (AMI) is excluded are an important determinant of emergency department (ED) length of stay and resource utilization. While high-sensitivity troponin I (hsTnI) >99th percentile (upper reference level [URL]) represents a "rule-in" cutpoint, our purpose was to evaluate the ability of the Beckman Coulter hsTnI assay, using various level-of-quantification (LoQ) cutpoints, to rule out AMI within 3 hours of ED presentation in suspected acute coronary syndrome (ACS) patients.

METHODS

This multicenter evaluation enrolled adults with >5 minutes of ACS symptoms and an electrocardiogram obtained per standard care. Exclusions were ST-segment elevation or chronic hemodialysis. After informed consent was obtained, blood samples were collected in heparin at ED admission (baseline), ≥1 to 3, ≥3 to 6, and ≥6 to 9 hours postadmission. Samples were processed and stored at -20°C within 1 hour and were tested at three independent clinical laboratories on an immunoassay system (DxI 800, Beckman Coulter). Analytic cutpoints were the URL of 17.9 ng/L and two LoQ cutpoints, defined as the 10 and 20% coefficient of variation (5.6 and 2.3 ng/L, respectively). A criterion standard MI diagnosis was adjudicated by an independent endpoint committee, blinded to hsTnI, and using the universal definition of MI.

RESULTS

Of 1,049 patients meeting the entry criteria, and with baseline and 1- to 3-hour hsTnI results, 117 (11.2%) had an adjudicated final diagnosis of AMI. AMI patients were typically older, with more cardiovascular risk factors. Median (IQR) presentation time was 4 (1.6-16.0) hours after symptom onset, although AMI patients presented ~0.5 hour earlier than non-AMI. Enrollment and first blood draw occurred at a mean of ~1 hour after arrival. To evaluate the assay's rule-out performance, patients with any hsTnI > URL were considered high risk and were excluded. The remaining population (n = 829) was divided into four LoQ relative categories: both hsTnI < LoQ (Lo-Lo cohort); first hsTnI < LoQ and 2nd > LoQ (Lo-Hi cohort); first > LoQ and second < LoQ (Hi-Lo cohort); or both > LoQ (Hi-Hi cohort). In patients with any hsTnI result <20% CV LoQ (Groups 1-3), n = 231 (23.9% ruled out), AMI negative predictive value (NPV) was 100% (95% confidence interval [CI] = 98.9% to 100%). In patients with any hsTnI below the 10% LoQ, n = 611 (58% rule out), AMI NPV was 100% (95% CI = 99.5% to 100%). Of the Hi-Hi cohort (i.e., no hsTnI below the 10% LoQ, but both < URL), there were four AMI patients, NPV was 98.2% (95% CI = 95.4% to 99.3%), and sensitivity was 96.6.

CONCLUSIONS

Patients presenting >3 hours after the onset of suspected ACS symptoms, with at least two Beckman Coulter Access hsTnI < URL and at least one of which is below either the 10 or the 20% LoQ, had a 100% NPV for AMI. Two hsTnI values 1 to 3 hours apart with both < URL, but also >LoQ had inadequate sensitivity and NPV.

Healthcare and Resource Use in Patients With Stable High-Sensitivity Cardiac Troponin T Levels

Patients with elevated but stable levels of high-sensitivity cardiac troponin (hs-cTn) have a high risk of premature death and cardiovascular events. This study aimed to investigate the association between stable hs-cTnT levels and healthcare and resource use in patients with chest pain in the emergency department (ED). We included all patients who presented with chest pain and stable hs-cTnT levels without any concurrent acute medical condition at Karolinska University Hospital, Stockholm, Sweden, from 2011 to 2014. A negative binomial regression model was used to calculate incidence rates and incidence rate ratios with 95% confidence intervals (CIs) for the number of hospital visits, hospital days, and investigations performed during follow-up, in different categories of hs-cTnT levels (reference: hs-cTnT <5 ng/l). A total of 19,437 patients were included. During a follow-up of 4.1 years, 36,617 hospital visits and 206,808 hospital days were observed. Yearly rates of hospital visits and days gradually rose with increasing hs-cTnT levels from 0.3 and 1.27 (<5 ng/l) to 1.7 and 13 (≥50 ng/l) per person. In patients with hs-cTnT levels >14 ng/l, adjusted risks of in-hospital days were more than doubled (adjusted incidence rate ratio (95% CI) 2.31 (2.14 to 2.50), 2.88 (2.55 to 3.26), and 2.89 (2.45 to 3.40) in patients with hs-cTnT levels of 15 to 29, 30 to 49, and ≥50 ng/l, respectively) compared with the reference. Computed tomography, but not coronary angiography, increased with increasing hs-cTnT levels. In conclusion, stable hs-cTnT levels are associated with a higher rate of hospitalization, length of hospital stay, and resource use in patients with chest pain.

Comparative outcome analysis of stable mildly elevated high sensitivity troponin T in patients presenting with chest pain. A single-center retrospective cohort study

Background

The ideal high-sensitivity troponin (hsTn) cutoff for identifying those at low risk of 30 days events is debated; however, the 99th percentile overall or gender-specific upper reference limit (URL) is most commonly used. The magnitude of risk and the best management strategy for those with low-level hsTn elevation hasn't been extensively studied.

Methods

We conducted a retrospective cohort analysis including 4396 chest pain patients (542 with low-level hsTn elevation) who ruled out for myocardial infarction (MI), had a stable high-sensitivity troponin T (hsTnT) levels (defined as < 5 ng/l inter-measurements increase in hsTnT levels), and were discharged from the emergency department without further ischemic testing. The aim of the study was to compare the 30-day incidence of adverse cardiac events (ACE) between patients with undetectable high-sensitivity troponin T (hsTnT) (group 1), patients with hsTnT within the 99th percentile sex-specific URL (group 2), and patients with low-level hsTnT elevation (between the 99th percentile URL and ≤ 50 ng/l) (group 3).

Results

30-day event rates were very low 0.1%, 0.6%, and 0.4% for hsTnT groups 1, 2, and 3 respectively (overall P = 0.041, for groups 2 & 3 interaction P = 0.74). 30-day all-cause mortality, as well as 1-year all-cause and cardiovascular mortalities, occurred more frequently in those with low-level hsTnT elevation as did 1-year composite ACE.

Conclusion

In conclusion, 30-day adverse event rates were very low in those with stable low-level hsTnT elevation who ruled out for MI and were discharged from the emergency department without further inpatient testing.

High-Sensitivity Troponin-T and Cardiovascular Outcomes in the Community: Differences Between Women and Men

OBJECTIVE

To evaluate associations of high-sensitivity cardiac troponin-T (cTnT) with cardiovascular disease (CVD), heart failure (HF), and mortality in community-dwelling women and men.

PARTICIPANTS AND METHODS

A total of 8226 adults from the Prevention of Renal and Vascular End-stage Disease (PREVEND) cohort (1997-1998) were enrolled in a prospective observational study (mean age: 49 years; 50.2% women). Sex-specific associations of cTnT levels with future clinical outcomes were evaluated using adjusted Cox-regression models.

RESULTS

Measurable cTnT levels (≥3 ng/L) were detected in 1102 women (26.7%) and in 2396 men (58.5%). Baseline cTnT levels were associated with a greater risk of developing CVD in women than men [Hazard ratio (HR_women), 1.48 per unit increase in log₂-cTnT; 95% CI, 1.21 to 1.81 vs HR_men, 1.20; 95% CI, 1.07 to 1.35; P_interaction<.001]. Similar sex-related differences were observed for HF (P_interaction= .005) and mortality (P_interaction= .008). Further, compared with referent category (cTnT <3 ng/L), women with cTnT levels greater than or equal to 6 ng/L had a significantly increased risk for CVD (HR, 2.30; 95% CI, 1.45 to 3.64), HF (HR, 2.86; 95% CI, 1.41 to 5.80), and mortality (HR, 2.65; 95% CI, 1.52 to 4.61), whereas men with cTnT levels greater than or equal to 6 ng/L had a significantly increased risk only for CVD (HR, 1.51; 95% CI, 1.07 to 2.13).

CONCLUSION

Baseline cTnT levels were associated with future CVD, HF, and mortality in both sexes, and these associations were stronger in women. Future studies are needed to determine the value of cTnT in early diagnosis of CVD, particularly in women.

Mortality at 5 Years Among Very Elderly Patients Undergoing High Sensitivity Troponin T Testing for Suspected Acute Coronary Syndromes

BACKGROUND

Patients aged ≥80 years old often present to Emergency Departments (ED) with symptoms potentially due to an acute coronary syndrome (ACS). This study aimed to evaluate associations between baseline level(s) of high sensitivity troponin T (HsTnT), adjudicated diagnoses and outcomes.

METHODS

Consecutive patients aged ≥80 years were studied, who presented to the ED at Liverpool Hospital, NSW, Australia during the 4 months period March to June 2014 (inclusive) with symptoms suggestive of an ACS, and who had at least one HsTnT assay performed. Diagnoses were based on the fourth universal definition of MI (myocardial infarction) including type-1 MI, type-2 MI, acute myocardial injury, chronic myocardial injury; the rest were termed "other diagnoses". Patients were categorised by baseline HsTnT levels 1) ≤14 ng/L, 2) 15-29 ng/L, 3) 30-49 ng/L and 4) ≥50 ng/L.

RESULTS

Of 2,773 patients screened, 545 were aged ≥80 years (median age 85 [IQR 82-88]); median follow-up was 32 months (IQR 5-56). The respective rates of adjudicated diagnoses were type-I MI 3.1%, type-2 MI 13%, acute myocardial injury 9.5%, chronic myocardial injury 56% and 18.6% had other diagnoses. Mortality rates increased, irrespective of adjudicated diagnoses with increasing HsTnT levels (ng/L): 17% (16/96) for ≤14; 35% (67/194) for 15-29; 51% (65/127) for 30-49; and 64% (82/128) for ≥50 ng/L; log rank p≤0.001. On multi-variable analyses, after adjusting for potential confounding factors including age, hypertension, chronic kidney disease (CKD) and chronic obstructive pulmonary disease (COPD), MI type was not associated with late mortality.

CONCLUSIONS

Among patients aged ≥80 years higher HsTnT levels, irrespective of adjudicated diagnoses, were associated with increased mortality. Most very elderly patients presenting with symptoms suggestive of an ACS undergoing HsTnT testing in EDs had elevated levels most commonly due to chronic myocardial injury. Whether any interventions can modify outcomes require prospective evaluation.

Troponins and Natriuretic Peptides in Cardio-Oncology Patients-Data From the ECoR Registry

BACKGROUND

The long-term survival of cancer patients has significantly improved over the past years. Despite their therapeutic efficacy, various cancer therapies are associated with cardiotoxicity. Therefore, timely detection of cardiotoxic adverse events is crucial. However, the clinical assessment of myocardial damage caused by cancer therapy remains difficult.

METHODS

This retrospective study was performed to evaluate the diagnostic value of cardiac troponin I (cTnI) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) for monitoring cancer therapy-induced cardiomyopathy. A total of 485 cancer patients referred to our cardio-oncology unit between July 2018 and January 2020 were selected from our Essen Cardio-oncology Registry (ECoR). We included patients with all types of cancer. Plasma concentrations of cTnI and NT-proBNP were measured by radioimmunoassay, and two-dimensional left ventricular ejection fraction (2D-LVEF), diastolic function, and global longitudinal strain (GLS) were measured by transthoracic echocardiography. In 116 patients, assessment was conducted before the induction of cancer therapy and during a short-term follow-up period; n = 42 of these were treated for malignant melanoma, and n = 42 with serial measurements were under treatment for breast cancer.

RESULTS

In cross-sectional data, elevated NT-proBNP was associated with reduced LVEF and pathological GLS in the total cohort. A total of 116 patients had serial LVEF and biomarker measurements, and changes in NT-proBNP and troponin correlated with changes in LVEF during follow-up investigations. Similar to the total cohort, a subgroup of patients treated for malignant melanoma showed a correlation between the change in cTnI and the change in LVEF. In a subgroup analysis of patients undergoing breast cancer therapy, a correlation between the change in NT-proBNP and the change in LVEF could be detected. Thirty patients presented with chemotherapy-induced cardiomyopathy, defined as a significant LVEF decrease (> 10%) to a value below 50%. The number of patients with increased cTnI and NT-proBNP was significantly higher in patients with chemotherapy-induced cardiomyopathy than in patients without cardiotoxicity. Patients with positive cTnI and NT-proBNP were more likely to have a history of coronary heart disease, atrial fibrillation, and arterial hypertension.

CONCLUSION

Our data suggest that cardiac biomarkers play an important role in the detection of cancer therapy-induced cardiotoxicity. Larger systematic assessment in prospective cohorts is mandatory.

Causes of Death in Patients With Acute and Chronic Myocardial Injury

BACKGROUND

Information about causes of death in patients with myocardial injury is limited. The purpose of this study was to explore causes of death in patients with myocardial injury.

METHODS

In a cohort of 22,589 patients, 3853 patients with myocardial injury were identified and categorized into: type 1 myocardial infarction, type 2 myocardial infarction, and nonischemic acute and chronic myocardial injury. We included all 1466/3853 (38%) patients who died during follow-up (3.9 ± 2 years). We estimated rates and adjusted odds ratio (OR) with 95% confidence interval (CI) for causes of death in the 4 categories of myocardial injury using patients without myocardial injury 819/17,932 (4.6%) who died as reference.

RESULTS

The study cohort included 2285 patients. The proportion of cardiovascular deaths was higher in patients with type 1 myocardial infarction (48%), acute (43%), and chronic (45%) myocardial injury and type 2 myocardial infarction (39%) compared with patients without myocardial injury (25%). Adjusted rates for cardiovascular death were similar in patients with myocardial injury. Type 1 myocardial infarction, acute, and chronic myocardial injury was associated with a 77% (OR: 1.77, 95% CI 1.29-2.41), 40% (OR: 1.40, 95% CI: 1.07-1.84), and 36% (OR: 1.36, 95% CI: 1.05-1.76) higher risk of cardiovascular death.

CONCLUSIONS

Patients with type 1 myocardial infarction and acute or chronic myocardial injury have similar proportions and high risks for cardiovascular death. We believe that these findings stress the need for investigating patients without known heart diseases who present with nonischemic myocardial injury, or type 2 myocardial infarction.