Convalescent troponin and cardiovascular death following acute coronary syndrome

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.

Convalescent Growth Differentiation Factor-15 and Long-Term Outcomes after an Acute Coronary Syndrome

BACKGROUND

Growth differentiation factor-15 (GDF-15) has been shown to be associated with adverse clinical outcomes in patients after an acute coronary syndrome when measured soon after an event. Although dynamic in the acute phase after myocardial injury, GDF-15 has been shown to remain stable during convalescence. In this study, we aimed to assess the value of GDF-15 as a long-term prognostic marker for clinical outcomes when measured in the convalescent phase following an acute coronary syndrome.

METHODS

GDF-15 concentrations were measured in 1945 patients who were recruited between 2002 and 2009 to the Coronary Disease Cohort Study. For this analysis, follow-up was curtailed at 10 years and association of GDF-15 with all-cause death, cardiovascular death, recurrent myocardial infarction, and heart failure hospitalizations were assessed with multivariate Cox proportional hazard regression analysis.

RESULTS

After 10 years of follow-up, there were 648 deaths (348 from cardiovascular causes), 500 admissions for myocardial infarction, and 436 for heart failure. Four-month convalescent GDF-15 demonstrated a robust independent association with all endpoints, which remained after adjustment for Global Registry of Acute Coronary Events score and other convalescent biomarkers. When compared to the lowest quartile of GDF-15 concentrations, those in the highest quartile had a 3-fold increased risk of all-cause death.

CONCLUSIONS

Convalescent plasma GDF-15 is a strong and independent predictor of 10-year all-cause death, cardiovascular death, recurrent myocardial infarction, and heart failure admission following an acute coronary syndrome.

AUSTRALIAN NEW ZEALAND CLINICAL TRIALS REGISTRY TRIAL ID

ACTRN12605000431628.

High-Sensitivity Cardiac Troponin for Risk Assessment in Patients With Chronic Coronary Artery Disease

BACKGROUND

Cardiac troponin is used for risk stratification of patients with acute coronary syndromes; however, the role of testing in other settings remains unclear.

OBJECTIVES

The aim of this study was to evaluate whether cardiac troponin testing could enhance risk stratification in patients with chronic coronary artery disease independent of disease severity and conventional risk measures.

METHODS

In a prospective cohort of consecutive patients with symptoms suggestive of stable angina attending for outpatient coronary angiography, high-sensitivity cardiac troponin I was measured before angiography, and clinicians were blinded to the results. The primary outcome was myocardial infarction or cardiovascular death during follow-up.

RESULTS

In 4,240 patients (age 66 years [IQR: 59-73 years], 33% female), coronary artery disease was identified in 3,888 (92%) who had 255 (6%) primary outcome events during a median follow-up of 2.4 years (IQR: 1.3-3.6 years). In patients with coronary artery disease, troponin concentrations were 2-fold higher in those with an event compared with those without (6.7 ng/L [IQR: 3.2-14.2 ng/L] vs 3.3 ng/L [IQR: 1.7-6.6 ng/L]; P < 0.001). Troponin concentrations were associated with the primary outcome after adjusting for cardiovascular risk factors and coronary artery disease severity (adjusted HR: 2.3; 95% CI: 1.7-3.0, log10 troponin; P < 0.001). A troponin concentration >10 ng/L identified patients with a 50% increase in the risk of myocardial infarction or cardiovascular death.

CONCLUSIONS

In patients with chronic coronary artery disease, cardiac troponin predicts risk of myocardial infarction or cardiovascular death independent of cardiovascular risk factors and disease severity. Further studies are required to evaluate whether routine testing could inform the selection of high-risk patients for treatment intensification. (Myocardial Injury in Patients Referred for Coronary Angiography [MICA]; ISRCTN15620297).

The Clinical Validation of a Common Analytical Change Criteria for Cardiac Troponin for Ruling in an Acute Cardiovascular Outcome in Patients Presenting with Ischemic Chest Pain Symptoms

Serial cardiac troponin (cTn) testing on patients with symptoms suggestive of acute coronary syndrome (ACS) is primarily to identify those patients with evolving myocardial injury. With the improved analytical performance of the high-sensitivity cTn (hs-cTn) assays, different change criteria have been proposed that are mostly assay dependent. Here, we developed and compared a new Common Change Criteria (3C for the combined criteria of >3 ng/L, >30%, or >15% based on the initial cTn concentration of <10 ng/L, 10 to 100 ng/L, or >100 ng/L, respectively) method, versus the 2 h assay-dependent absolute change criteria endorsed by the European Society of Cardiology (ESC), versus the common relative >20% change criterion. These different analytical change criteria were evaluated in 855 emergency department (ED) patients with symptoms of ACS and who had two samples collected 3 h apart. The cTn concentrations were measured with four different assays (Abbott hs-cTnI, Roche hs-cTnT, Ortho cTnI-ES, and Ortho hs-cTnI). The outcomes evaluated were myocardial infarction (MI) and a composite outcome (MI, unstable angina, ventricular arrhythmia, heart failure, or cardiovascular death) within 7 days of ED presentation. The combined change criteria (3C) method yielded higher specificities (range: 93.9 to 97.2%) as compared to the >20% criterion (range: 42.3 to 88.1%) for all four assays for MI. The 3C method only yielded a higher specificity estimate for MI for the cTnI-ES assay (95.9%) versus the absolute change criteria (71.7%). Similar estimates were obtained for the composite outcome. There was also substantial agreement between hs-cTnT and the different cTnI assays for MI with the 3C method, with the percent agreement being ≥95%. The Common Change Criteria (3C) method combining both absolute and different percent changes may be used with cTnI, hs-cTnT, and different hs-cTnI assays to yield similar high-specificity (rule-in) estimates for adverse cardiovascular events for patients presenting to the ED with ACS symptoms.

Cardiac Troponin Testing in Patients with COVID-19: A Strategy for Testing and Reporting Results

BACKGROUND

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that emerged late in 2019 causing COVID-19 (coronavirus disease-2019) may adversely affect the cardiovascular system. Publications from Asia, Europe, and North America have identified cardiac troponin as an important prognostic indicator for patients hospitalized with COVID-19. We recognized from publications within the first 6 months of the pandemic that there has been much uncertainty on the reporting, interpretation, and pathophysiology of an increased cardiac troponin concentration in this setting.

CONTENT

The purpose of this mini-review is: a) to review the pathophysiology of SARS-CoV-2 and the cardiovascular system, b) to overview the strengths and weaknesses of selected studies evaluating cardiac troponin in patients with COVID-19, and c) to recommend testing strategies in the acute period, in the convalescence period and in long-term care for patients who have become ill with COVID-19.

SUMMARY

This review provides important educational information and identifies gaps in understanding the role of cardiac troponin and COVID-19. Future, properly designed studies will hopefully provide the much-needed evidence on the path forward in testing cardiac troponin in patients with COVID-19.

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Long-Term Prognostic Significance of High-Sensitive Troponin I Increase during Hospital Stay in Patients with Acute Myocardial Infarction and Non-Obstructive Coronary Arteries

Background and Objectives: A topic already widely investigated is the negative prognostic value regarding the extent of high sensitive troponin I (hs-TnI) increases among patients with myocardial infarction (MI) and obstructive coronary atherosclerosis compared to a group of patients with MI and non-obstructive coronary atherosclerosis (MINOCA). Thus, the aim of this study was to evaluate the prognostic value concerning the extent of hs-TnI increase on clinical outcomes among patients with a MINOCA working diagnosis. Materials and Methods: We selected 337 consecutive patients admitted to hospital with a working diagnosis of MINOCA. The patients were divided in three groups according to the extent of hs-TnI increase during hospitalization (increase ≤5-times above the limit of the upper norm, >5 and ≤20-times, and >20-times). The study endpoints included all-cause mortality and major adverse cardiac and cerebrovascular events (MACCE; cerebral stroke and transient ischemic attacks, MI, coronary artery revascularization, either percutaneous coronary intervention or coronary artery bypass grafting and all-cause mortality). Results: During the mean follow-up period of 516.1 ± 239.8 days, using Kaplan-Meier survival curve analysis, significantly higher mortality rates were demonstrated among patients from the group with the greatest hs-TnI increase compared to the remaining groups (p = 0.01) and borderline values for MACCE (p = 0.053). Multivariable cox regression analysis did not confirm hs-TnI among factors related to increased MACCE or all-cause mortality rates. Conclusion: While a relationship between clinical outcomes and the extent of the hs-TnI increase among patients with a MINOCA working diagnosis remains, it does not seem to be not as strong as it is in patients with obstructive coronary atherosclerosis.

Dynamic Changes in High-Sensitivity Cardiac Troponin I in Response to Anthracycline-Based Chemotherapy

AIMS

Treatment advances have improved cancer-related outcomes and shifted interest towards minimising long-term iatrogenic complications, particularly chemotherapy-related cardiotoxicity. High-sensitivity cardiac troponin I (hs-cTnI) assays accurately quantify very low concentrations of plasma troponin and enable early detection of cardiomyocyte injury prior to the development of myocardial dysfunction. The profile of hs-cTnI in response to anthracycline-based treatment has not previously been described.

MATERIALS AND METHODS

This was a multicentre prospective observational cohort study. Female patients with newly diagnosed invasive breast cancer scheduled to receive anthracycline-based (epirubicin) chemotherapy were recruited. Blood sampling was carried out before and 24 h after each cycle. Hs-cTnI concentrations were measured using the Abbott ARCHITECT_STAT assay.

RESULTS

We recruited 78 women with a median (interquartile range) age of 52 (49-61) years. The median baseline troponin concentration was 1 (1-4) ng/l and the median cumulative epirubicin dose was 394 (300-405) mg/m². Following an initial 33% fall 24 h after anthracycline dosing (P < 0.001), hs-cTnI concentrations increased by a median of 50% (P < 0.001) with each successive treatment cycle. In total, 45 patients had troponin measured immediately before the sixth treatment cycle, 21 (46.6%) of whom had hs-cTnI concentrations ≥16 ng/l, indicating myocardial injury. Plasma hs-cTnI concentrations before the second treatment cycle were a strong predictor of subsequent myocardial injury.

CONCLUSIONS

Cardiotoxicity arising from anthracycline therapy is detectable in the earliest stages of breast cancer treatment and is cumulative with each treatment cycle. This injury is most reliably determined from blood sampling carried out before rather than after each treatment cycle.