Performance of the European Society of Cardiology 0/1-hour algorithm with high-sensitivity cardiac troponin T at 90 days among patients with known coronary artery disease

BACKGROUND

The European Society of Cardiology (ESC) 0/1-h high sensitivity troponin T (hs-cTnT) algorithm does not differentiate risk based on known coronary artery disease (CAD: prior myocardial infarction [MI], coronary revascularization, or ≥ 70% coronary stenosis). We recently evaluated its performance among patients with known CAD at 30-days, but little is known about its longer-term risk prediction. The objective of this study is to determine and compare the performance of the algorithm at 90-days among patients with and without known CAD.

METHODS

We performed a pre-planned subgroup analysis of the STOP-CP cohort, which prospectively enrolled ED patients ≥21 years old with symptoms suggestive of ACS without ST-elevation on initial ECG across 8 US sites (1/25/2017-9/6/2018). Participants with 0- and 1-h hs-cTnT measures (Roche, Basel, Switzerland) were stratified into rule-out, observe, and rule-in groups using the ESC 0/1-h algorithm. Algorithm performance was tested among patients with or without known CAD, as determined by the treating provider. The primary outcome was cardiac death or MI at 90-days. Fisher's exact tests were used to compare 90-day event and rule-out rates between patients with and without known CAD. Negative predictive values (NPVs) for 90-day cardiac death or MI with exact 95% confidence intervals were calculated and compared using Fisher's exact test.

RESULTS

The STOP-CP study accrued 1430 patients, of which 31.4% (449/1430) had known CAD. Cardiac death or MI at 90 days was more common in patients with known CAD than in those without [21.2% (95/449) vs. 10.0% (98/981); p < 0.001]. Using the ESC 0/1-h algorithm, 39.6% (178/449) of patients with known CAD and 66.1% (648/981) of patients without known CAD were ruled-out (p < 0.001). Among rule-out patients, 90-day cardiac death or MI occurred in 3.4% (6/178) of patients with known CAD and 1.2% (8/648) without known CAD (p = 0.09). NPV for 90-day cardiac death or MI was 96.6% (95%CI 92.8-98.8) among patients with known CAD and 98.8% (95%CI 97.6-99.5) in patients without known CAD (p = 0.09).

CONCLUSION

Patients with known CAD who were ruled-out using the ESC 0/1-h hs-cTnT algorithm had a high rate of missed 90-day cardiac events, suggesting that the ESC 0/1-h hs-cTnT algorithm may not be safe for use among patients with known CAD.

TRIAL REGISTRATION

High-Sensitivity Cardiac Troponin T to Optimize Chest Pain Risk Stratification (STOP-CP; ClinicalTrials.gov: NCT02984436; https://clinicaltrials.gov/ct2/show/NCT02984436).

Effect of transitioning from conventional cardiac troponin to high-sensitivity cardiac troponin on resource utilization- a single center experience

BACKGROUND

Compared to conventional cardiac troponin (cTn), the high-sensitivity cardiac troponin (hs-cTn) assay is associated with improved detection of myocardial infarction (MI).

METHODS

We performed a descriptive retrospective analysis of resource utilization at Rush University Medical Center over the transition period (July 1, 2021) from a cTn to a hs-cTn assay. Inclusion criteria included emergency department (ED) encounters between January 1 to December 31, 2021, with chief complaints of "chest pain" or "dyspnea" with associated troponin orders. The primary endpoint was the percentage of ED discharges. Secondary endpoints included the number of cardiac studies ordered. Univariable comparisons of these endpoints were performed using Student's t-test for continuous variables and Chi-square tests for binary/categorical variables.

RESULTS

A total of 5113 encounters were analyzed. Hs-cTn was associated with an overall increase in ED patient discharges with negative troponin tests (44.1% vs. 29.9%, P < 0.01). In terms of cardiac testing per encounter, hs-cTn was associated with significant increases in the number of troponin tests (1.9 vs. 1.6, P < 0.01), electrocardiograms (3.0 vs. 2.9, P = 0.01), and echocardiograms (0.5 vs. 0.4, P < 0.01). There was a significant decrease in the utilization of stress testing (0.21 vs. 0.26, P < 0.01). There was a significant increase in total coronary angiography use during the hs-cTn period compared to cTn (227/2471 (9.2%) vs. 195/2642 (7.4%), P = 0.02).

CONCLUSION

Transitioning from cTn to hs-cTn was associated with significantly increased ED discharges and an increase in troponin tests, ECG, echocardiograms, and coronary angiograms. There was a decrease in the number of stress tests.

Introduction of a high sensitivity troponin reduces ED length of stay

BACKGROUND

High sensitivity cardiac troponins (hs-cTn) allow earlier identification and exclusion of acute myocardial infarction. We determined if transitioning from contemporary to high sensitivity troponin T (hs-cTnT) would reduce ED length of stay in chest pain (CP) patients.

METHODS

We conducted a pragmatic, prospective, before and after study of implementing a hs-cTnT by reviewing the electronic health records in all adult ED patients presenting to a large, suburban academic medical center during the 3 months before and after transitioning from a 4th generation troponin to a 5th generation hs-cTnT (Elecsys® Troponin T-high sensitive, Roche Diagnostics, Indianapolis, IN).

RESULTS

There were 1431 and 1437 CP patients before and after the intervention. Mean (SD) age was 51.5 (18) yrs. and 54.3% were female. The median (IQR) ED LOS for chest pain patients directly discharged to home was 6.2 (4.7-8.4) and 5.3 (4.0-7.2) hours before and after introducing hs-cTn respectively; difference 47 min (95%CI, 35-59); P < 0.001. The median (IQR) ED LOS for chest pain patients admitted to the hospital was 9.5 (6.6-13.8) and 8.1 (5.7-11.2) hours before and after introducing hs-cTn respectively; difference 77 min (95%CI, 35-121); P < 0.001. Overall admission rates (22 vs 21% both before and after) did not change during the study. The rates of computed tomography coronary angiography before and after the intervention were 21 and 20.4% respectively. The rates of invasive coronary angiography before and after the intervention were 5.8 and 5.6% respectively.

CONCLUSIONS

Transitioning to a hs-cTnT is associated with a clinically relevant and statistically significant reduction in ED LOS for both discharged and admitted patients with and without CP with no increase in admission or coronary angiography rates.

Is high sensitivity troponin, taken regardless of a clinical indication, associated with 1 year mortality in critical care patients?

The aim of this study was to assess whether high sensitivity troponin (hs-cTnI) is associated with 1 year mortality in critical care (CC). One year mortality data were obtained from NHS Digital for a consecutive cohort of patients admitted to general CC unit (GCCU) and neuroscience CC unit (NCCU) who had hs-cTnI tests performed throughout their CC admission, regardless of whether the test was clinically indicated. Cox proportional hazards were used to estimate the risk of 1-year mortality. A landmark analysis was undertaken to assess whether any relationship at 1 year was driven by mortality within the first 30 days. A total of 1033 consecutive patients were included. At 1 year 254 (24.6%) patients had died. The admission log(10)hs-cTnI concentration in the entire cohort (HR 1.35 (95% CI 1.05-1.75) p = 0.009 with a bootstrap of 1000 samples) was independently associated with 1 year mortality. On landmark analysis the association with 1 year mortality was driven by 30 day mortality. These results indicate that admission hs-cTnI concentration is independently associated with 1 year mortality in CC and this relationship may be driven by differences in mortality at 30 days.

Impact of a high sensitivity troponin accelerated diagnostic protocol on the safety and emergency department length of stay of chest pain in an academic tertiary hospital: a quality improvement study

PURPOSE

High-sensitivity troponin (hsTn) accelerated diagnostic protocols are highly recommended for evaluating acute coronary syndromes. Our goal was to improve care for chest pain patients through the safe adoption of an accelerated diagnostic protocol in our academic Emergency Department (ED) with an aim to reduce mean ED length of stay for chest pain patients by 1 h over 1.5 years. Pre-accelerated diagnostic protocol, our mean ED length of stay for chest pain patients was 9.0 h.

METHODS

Using the Model for Improvement, we implemented a two-hour accelerated diagnostic protocol and conducted two Plan-Do-Study-Act cycles and education efforts to improve accelerated diagnostic protocol compliance and decrease ED length of stay. Using control charts, we measured the mean monthly ED length of stay for chest pain patients to look for special cause evidence of improvement. Process measures measured compliance with the accelerated diagnostic protocol. Balancing measures included the ED length of stay for abdominal pain patients and the number of admissions and deaths at 7 days for chest pain patients.

RESULTS

Mean ED length of stay for chest pain patients decreased from 9.0 to 8.2 h post-accelerated diagnostic protocol. The mean time between troponins decreased from 3.9 to 3.0 h, and the percentage of second troponins repeated at < 2.75 h increased from 22.3% to 58.6%. For abdominal pain patients, ED length of stay decreased from 10.8 to 10.5 h. No chest pain patients died within 7 days pre- or post-accelerated diagnostic protocol. Pre-accelerated diagnostic protocol, 0.84% (41/4,905) were admitted within 7 days. Post-accelerated diagnostic protocol and accelerated diagnostic protocol compliant, 0.70% (13/1,844) were admitted. Post-accelerated diagnostic protocol and accelerated diagnostic protocol non-compliant, 1.1% (13/1,183) were admitted.

CONCLUSION

We safely introduced a hsTn accelerated diagnostic protocol in an academic ED. ED length of stay decreased for chest pain patients but did not meet our 1-h goal.

Evaluating the Utility of High Sensitivity Troponin in Blunt Cardiac Injury

INTRODUCTION

Screening for blunt cardiac injury (BCI) includes obtaining a serum troponin level and an electrocardiogram for patients diagnosed with a sternal fracture. Our institution has transitioned to the use of a high sensitivity troponin I (hsTnI). The aim of this study was to determine whether hsTnI is comparable to troponin I (TnI) in identifying clinically significant BCI.

MATERIALS AND METHODS

Trauma patients presenting to a level I trauma center over a 24-mo period with the diagnosis of sternal fracture were screened for BCI. Any initial TnI more than 0.04 ng/mL or hsTnI more than 18 ng/L was considered positive for potential BCI. Clinically significant BCI was defined as a new-bundle branch block, ST wave change, echocardiogram change, or need for cardiac catheterization.

RESULTS

Two hundred sixty five patients with a sternal fracture were identified, 161 underwent screening with TnI and 104 with hsTnI. For TnI, the sensitivity and specificity for detection of clinically significant BCI was 0.80 and 0.79, respectively. For hsTnI, the sensitivity and specificity for detection of clinically significant BCI was 0.71 and 0.69, respectively. A multivariate analysis demonstrated the odds ratio for significant BCI with a positive TnI was 14.4 (95% confidence interval, 3.9-55.8, P < 0.0001) versus an odds ratio of 5.48 (95% confidence interval 1.9-15.7, P = 0.002) in the hsTnI group.

CONCLUSIONS

The sensitivity of hsTnI is comparable to TnI for detection of significant BCI. Additional investigation is needed to determine the necessity and interval for repeat testing and the need for additional diagnostic testing.

Serial cardiac biomarkers for risk stratification of patients with COVID-19

OBJECTIVES

Several studies have demonstrated an association between elevated cardiac biomarkers and adverse outcomes in patients with COVID-19. However, the prognostic and predictive capability of a multimarker panel in a prospectively collected, diverse "all-comers" COVID-19 population has not been fully elucidated.

DESIGN & METHODS

We prospectively assessed high sensitivity cardiac troponin I (hsTnI), NT-pro B-type Natriuretic Peptide (NT-proBNP), Galectin-3 (Gal-3), and procalcitonin (PCT) in 4,282 serial samples from 358 patients admitted with symptomatic, RT-PCR confirmed SARS-CoV-2 infection. Outcomes examined were 30-day in-hospital mortality and requirement for intubation within 10 days.

RESULTS

Baseline hsTnI had the highest AUC for predicting 30-day mortality (0.81; 95% CI, 0.73-0.88), followed by NT-proBNP (0.80; 0.74-0.86), PCT (0.77; 0.70-0.84), and Gal-3 (0.68; 0.60-0.76). HsTnI < 3.5 ng/L at baseline identified patients at low risk for in-hospital mortality (NPV 95.9%, sensitivity 97.3%) and 10-day intubation (NPV 90.4%, sensitivity 88.5%). Continuous, log-2 increases in troponin concentration were associated with reduced survival (p < 0.001) on Kaplan-Meier curves and increased risk of 30-day mortality: HR 1.26 (1.16-1.37) in univariate and 1.19 (1.03-1.4) in multivariate models. Time-varying doubling of concentrations of hsTnI and Gal-3 were associated with increased risk of 30-day mortality (adjusted HR 1.21, 1.06-1.4, and 1.92, 1.40-2.6).

CONCLUSION

HsTnI, NT-proBNP, Gal-3, and PCT are elevated at baseline in patients that have worse outcomes from COVID-19. HsTnI was the only independent predictor of 30-day mortality and intubation. Time-varying, doubling in hsTnI and Gal-3 further aided in prognostication of adverse outcomes. These results support the use of hsTnI for triaging patients with COVID-19.

Elderly patients with non-cardiac admissions and elevated high-sensitivity troponin: the prognostic value of renal function

BACKGROUND

High-sensitivity cardiac troponin (hs-cTn) levels are frequently elevated in elderly patients presenting to the emergency department for non-cardiac events. However, most studies on the role of elevated hs-cTn in elderly populations have investigated the prognostic value of hs-cTn in patients with a specific diagnosis or have assessed the relationship between hs-cTn and comorbidities.

AIM

To investigate the in-hospital prognosis of consecutive elderly patients admitted to the Internal Medicine Department with acute non-cardiac events and increased hs-cTnI levels.

METHODS

In this retrospective study, we selected patients who were aged ≥ 65 years and admitted to the Internal Medicine Department of our hospital between January 2019 and December 2019 for non-cardiac reasons. Eligible patients were those who had hs-cTnI concentrations ≥ 100 ng/L. We investigated the independent predictors of in-hospital mortality by multivariable logistic regression analysis.

RESULTS

One hundred and forty-six patients (59% female) were selected with an age range from 65 to 100 (mean ± SD: 85.4 ± 7.61) years. The median hs-cTnI value was 284.2 ng/L. For 72 (49%) patients the diagnosis of hospitalization was an infectious disease. The overall in-hospital mortality was 32% (47 patients). Individuals who died did not have higher hs-cTnI levels compared with those who were discharged alive (median: 314.8 vs 282.5 ng/L; P = 0.565). There was no difference in mortality in patients with infectious vs non-infectious disease (29% vs 35%). Multivariable analysis showed that age (OR 1.062 per 1 year increase, 95%CI: 1.000-1.127; P = 0.048) and creatinine levels (OR 2.065 per 1 mg/dL increase, 95%CI: 1.383-3.085; P < 0.001) were the only independent predictors of death. Mortality was 49% in patients with eGFR < 30 mL/min/1.73 m².

CONCLUSION

Myocardial injury is a malignant condition in elderly patients admitted to the hospital for non-cardiac reasons. The presence of severe renal impairment is a marker of extremely high in-hospital mortality.

RACE-IT - Rapid Acute Coronary Syndrome Exclusion using the Beckman Coulter Access high-sensitivity cardiac troponin I: A stepped-wedge cluster randomized trial

BACKGROUND

Protocols utilizing high-sensitivity cardiac troponin (hs-cTn) assays for the evaluation of suspected acute coronary syndrome (ACS) in the emergency department (ED) have been gaining popularity across the US and the world. These protocols more rapidly rule-out ACS and more accurately identify the presence of acute myocardial injury. At this time, few randomized trials have evaluated the safety and operational impact of these assays, resulting in limited evidence to guide the use and implementation of hs-cTn in the ED.

OBJECTIVE

The main study objective is to test the effectiveness of a rapid ACS rule-out pathway using hs-cTnI in safely discharging patients from the ED for whom clinical suspicion for ACS exists.

DESIGN

This prospective, implementation trial (n = 11,070) will utilize a stepped wedge cluster randomized trial design. The design will allow for all participating sites to capture benefit from the implementation of the hs-cTnI pathway while providing data evaluating the effectiveness in providing safe and rapid evaluation of patients with clinical suspicion for ACS.

SUMMARY

Demonstrating that clinical pathways using hs-cTnI can be effectively implemented to rapidly rule-out ACS while conserving costly hospital resources has significant implications for the care of patients with possible acute cardiac conditions in EDs across the US.

CLINICALTRIALSGOV IDENTIFIER

NCT04488913.

Mid-Term Survival and Risk Factors Associated With Myocardial Injury After Fenestrated and/or Branched Endovascular Aortic Aneurysm Repair

OBJECTIVE

Myocardial injury after non-cardiac surgery (MINS) is an independent predictor of post-operative mortality in non-cardiac surgery patients and may increase health costs. Few data are available for MINS in vascular surgery patients, in general, and those undergoing fenestrated/branched endovascular aortic repairs (F/BEVAR), in particular. The incidence of MINS after F/BEVAR, the associated risk factors, and prognosis have not been determined. The aim of the present study was to help fill these knowledge gaps.

METHODS

A single centre, retrospective study was carried out at a high volume F/BEVAR centre in a university hospital. Adult patients who underwent F/BEVAR between October 2010 and December 2018 were included. A high sensitivity troponin T (HsTnT) assay was performed daily in the first few post-operative days. MINS was defined as a HsTnT level ≥ 14 ng/L (MINS₁₄) or ≥ 20 ng/L (MINS₂₀). After assessment of the incidence of MINS, survival up to two years was estimated in a Kaplan-Meier analysis and the groups were compared according to MINS status. A secondary aim was to identify predictors of MINS.

RESULTS

Of the 387 included patients, 240 (62.0%) had MINS₁₄ and 166 (42.9%) had MINS₂₀. In multivariable Cox models, both conditions were significantly associated with poor two year survival (MINS14: adjusted hazard ratio [aHR] 2.15, 95% confidence interval [CI] 1.10 - 4.19; MINS₂₀: aHR 2.43, 95% CI 1.36 - 4.34). In a multivariable logistic regression, age, revised cardiac risk index, duration of surgery, pre-operative estimated glomerular filtration rate (eGFR), and haemoglobin level were independent predictors of MINS.

CONCLUSION

After F/BEVAR surgery, the incidence of MINS was particularly high, regardless of the definition considered (MINS₁₄ or MINS₂₀). MINS was significantly associated with poor two year survival. The modifiable predictors identified were duration of surgery, eGFR, and haemoglobin level.

High sensitivity troponin measurement in critical care: Flattering to deceive or 'never means nothing'?

INTRODUCTION

Troponin elevation is central to the diagnosis of acute type 1 myocardial infarction. It is, however, elevated in a range of other conditions, including type 2 myocardial infarction, and this setting is increasingly associated with adverse clinical outcomes. Patients within intensive care frequently have at least one organ failure together with a range of co-morbidities. Interpretation of troponin assay results in this population is challenging. This clinical uncertainty is compounded by the introduction of ever more sensitive troponin assays.

AREAS COVERED

The aims of this review are to (a) describe the currently available literature about the use of troponin assays in intensive care, (b) analyse the challenges presented by the introduction of increasingly sensitive troponin assays and (c) assess whether the role of troponin assays in intensive care may change in the future, dependent upon recent and ongoing research suggesting that they are predictive of outcome regardless of the underlying cause: the 'never means nothing' hypothesis.

COVID-19 and Acute Heart Failure: Screening the Critically Ill - A Position Statement of the Cardiac Society of Australia and New Zealand (CSANZ)

Up to one-third of COVID-19 patients admitted to intensive care develop an acute cardiomyopathy, which may represent myocarditis or stress cardiomyopathy. Further, while mortality in older patients with COVID-19 appears related to multi-organ failure complicating acute respiratory distress syndrome (ARDS), the cause of death in younger patients may be related to acute heart failure. Cardiac involvement needs to be considered early on in critically ill COVID-19 patients, and even after the acute respiratory phase is passing. This Statement presents a screening algorithm to better identify COVID-19 patients at risk for severe heart failure and circulatory collapse, while balancing the need to protect health care workers and preserve personal protective equipment (PPE). The significance of serum troponin levels and the role of telemetry and targeted transthoracic echocardiography (TTE) in patient investigation and management are addressed, as are fundamental considerations in the management of acute heart failure in COVID-19 patients.

Chest pain with less than 20% change in high sensitivity troponin T - a low risk cohort?

Background: Patients with chest pain are risk-stratified using serial high-sensitivity troponin (T) assays (hsTnT). Those with change in (Δ)hsTnT <20% are often categorised as low-risk and are less likely to be managed as acute coronary syndromes (ACS). We sought to characterise such a population of 'low-risk' chest pain presenters.Methods: We performed a retrospective cohort analysis of sequential patients admitted to our centre over a 1-year period with chest pain, absence of ST-elevation, with elevated hsTnT concentrations, and compared demographic, clinical and outcome data according to ΔhsTnT.Results: Three hundred and eleven patients were subdivided by ΔhsTnT [<20% (n = 80), 20-100% (n = 78), >100% (n = 153)]. Baseline demographic data were well-matched across the three subgroups; atrial fibrillation was more common in the two lower magnitude ΔhsTnT groups. Obstructive coronary artery disease (CAD) - while less common in those with ΔhsTnT <20% (66.2%) compared to the 20-100% (73.1%) and >100% (75.9%) groups (p = 0.03) - remained high in this lower risk group, and indeed revascularisation occurred in >60% of patients, equally frequently in all three groups. Using absolute ΔhsTnT ≥9ng/L within the ΔhsTnT <20% group provided incremental value in ruling in ACS, with a positive predictive value of 74.1%. ΔhsTnT was a univariate but not a multivariate predictor of obstructive CAD.Conclusions: Obstructive CAD and need for revascularisation are frequent in chest pain presenters with ΔhsTnT <20%. The increasing focus on hsTnT algorithms to exclude ACS and promote early discharge without adequate clinical risk stratification modelling risks misdiagnosis of patients presenting with acute myocardial ischaemia with a low-level hsTnT rise.

High-Sensitivity Cardiac Troponin I Levels in Normal and Hypertensive Pregnancy

PURPOSE

The purpose of this study was to examine the association of circulating concentrations of high-sensitivity cardiac troponin I (hs-cTn) in the various trimesters of pregnancy in patients with and without hypertension.

METHODS

This was a prospective cross-sectional study of pregnant and postnatal women aged between 18-35 years with no coexisting diseases. Serum samples were analysed for hs-TnI.

RESULTS

A total of 880 women (mean age = 29.1 years [standard deviation = 5.1 years]) were recruited with 129 (14%), 207 (24%), and 416 (47%) patients in the first, second, and third trimesters, respectively. Ninety (10%) participants were recruited in the postnatal period. During pregnancy 28 (3%) patients were classified as having pregnancy-induced hypertension and 10 (1%) as preeclampsia. High-sensitivity cardiac troponin I was measurable in 546 (62%) participants with a median of 1 ng/L (range 0 to 783 ng/L). Troponin concentrations were above the 99th percentile in 19 (2%) individuals. Patients with pregnancy-induced hypertension and preeclampsia had higher concentrations of hs-TnI (median 11 ng/L [interquartile range (IQR) 6 to 22 ng/L] vs 12ng/L [IQR 3 to 98 ng/L] vs 1 ng/L [IQR 0 to 1 ng/L]). In logistic regression modeling hs-cTnI concentration remained an independent predictor of pregnancy-induced hypertension or preeclampsia in both unadjusted and adjusted models (odds ratio 9.3 [95% confidence interval 5.8 to 16.3] and 11.5 [95% confidence interval 6.3 to 24.1], respectively, per doubling of hs-TnI concentrations).

CONCLUSIONS

Cardiac troponin measured using a high-sensitivity assay is quantifiable in the majority of young pregnant women with 2% of individuals having concentration above the 99th percentile sex-specific threshold. Patients with pregnancy-induced hypertension or preeclampsia had higher cardiac troponin concentrations. Cardiac troponin was a strong independent predictor of pregnancy-induced hypertension or preeclampsia in pregnant and postnatal women.

Unstable angina in the era of high-sensitivity troponin testing: a genuine entity and a cautionary tale

High-sensitivity cardiac troponin assays have emerged as a powerful tool in the management of patients presenting acutely to hospital with suspected cardiac chest pain. Recent guidelines emphasize the reassurance offered by low troponin concentrations early after admission. We describe a patient with known coronary artery disease, who presented with a classical history of recurrent myocardial ischaemia. High-sensitivity cardiac Troponin-I concentrations remained in the low-normal sex-specific reference range, despite serial testing on the day of admission, and despite recurrent pain with dynamic ECG changes. Urgent coronary angiography confirmed severe multi-vessel disease. He required an intra-aortic balloon pump within 24 h due to clinical instability, and had urgent coronary artery bypass surgery a few days later. This case confirms that "unstable angina" remains a genuine entity. It highlights the hazards of over-reliance on any single test and serves as a reminder of the importance of integrating tests with clinical assessment.

A direct comparison of decision rules for early discharge of suspected acute coronary syndromes in the era of high sensitivity troponin

BACKGROUND

We tested the hypothesis that a single high sensitivity troponin at limits of detection (LOD HSTnT) (<5 ng/l) combined with a presentation non-ischaemic electrocardiogram is superior to low-risk Global Registry of Acute Coronary Events (GRACE) (<75), Thrombolysis in Myocardial Infarction (TIMI) (≤1) and History, ECG, Age, Risk factors and Troponin (HEART) score (≤3) as an aid to early, safe discharge for suspected acute coronary syndrome.

METHODS

In a prospective cohort study, risk scores were computed in consecutive patients with suspected acute coronary syndrome presenting to the Emergency Room of a large English hospital. Adjudication of myocardial infarction, as per third universal definition, involved a two-physician, blinded, independent review of all biomarker positive chest pain re-presentations to any national hospital. The primary and secondary outcome was a composite of type 1 myocardial infarction, unplanned coronary revascularisation and all cause death (MACE) at six weeks and one year.

RESULTS

Of 3054 consecutive presentations with chest pain 1642 had suspected acute coronary syndrome (52% male, median age 59 years, 14% diabetic, 20% previous myocardial infarction). Median time from chest pain to presentation was 9.7 h. Re-presentations occurred in eight hospitals with 100% follow-up achieved. Two hundred and eleven (12.9%) and 279 (17%) were adjudicated to suffer MACE at six weeks and one year respectively. Only HEART ≤3 (negative predictive value MACE 99.4%, sensitivity 97.6%, %discharge 53.4) and LOD HSTnT strategy (negative predictive value MACE 99.8%, sensitivity 99.5%, %discharge 36.9) achieved pre-specified negative predictive value of >99% for MACE at six weeks. For type 1 myocardial infarction alone the negative predictive values at six weeks and one year were identical, for both HEART ≤3 and LOD HSTnT at 99.8% and 99.5% respectively.

CONCLUSION

HEART ≤3 or LOD HSTnT strategy rules out short and medium term myocardial infarction with ≥99.5% certainty, and short-term MACE with >99% certainty, allowing for early discharge of 53.4% and 36.9% respectively of suspected acute coronary syndrome. Adoption of either strategy has the potential to greatly reduce Emergency Room pressures and minimise follow-up investigations. Very early presenters (<3 h), due to limited numbers, are excluded from these conclusions.

High sensitivity troponin T and I reflect mitral annular plane systolic excursion being assessed by cardiac magnetic resonance imaging

Purpose

This study aims to evaluate the association between high sensitivity troponins (hsTn) and mitral annular plane systolic excursion (MAPSE) in patients undergoing cardiac magnetic resonance imaging (cMRI).

Methods

Patients undergoing cMRI were prospectively enrolled. Patients with right ventricular dysfunction (< 50%) were excluded. Blood samples for measurements of hsTn and amino-terminal pro-brain natriuretic peptide (NT-proBNP) were collected at the time of cMRI.

Results

84 patients were included. Median left ventricular ejection fraction was 59% (IQR 51–64%). HsTn were correlated inversely with MAPSE within multivariable linear regression models (hsTnI: Beta − 0.19; T − 1.96; p = 0.05; hsTnT: Beta − 0.26; T − 3.26; p = 0.002). HsTn increased significantly according to decreasing stages of impaired MAPSE (p < 0.003). HsTn discriminated patients with impaired MAPSE < 11 mm (hsTnT: AUC = 0.67; p = 0.008; hsTnI: AUC = 0.64; p = 0.03) and < 8 mm (hsTnT: AUC = 0.79; p = 0.0001; hsTnI: AUC = 0.75; p = 0.001) and were still significantly associated in multivariable logistic regression models with impaired MAPSE < 11 mm (hsTnT: OR = 4.71; p = 0.002; hsTnI: OR = 4.22; p = 0.009).

Conclusions

This study demonstrates that hsTn are able to reflect MAPSE being assessed by cMRI.

Electronic supplementary material

The online version of this article (doi:10.1186/s40001-017-0281-x) contains supplementary material, which is available to authorized users.

Impact of the Australian gender specific thresholds using the Abbott high sensitivity troponin I assay in clinical care

The aim of this study was to ascertain the impact of gender specific hs-TnI thresholds in a clinical setting and determine the clinical characteristics and discharge diagnosis for individuals presenting to the Emergency Department (ED) with elevated troponin I with the Abbott high-sensitivity troponin I (hs-TnI) assay, but non-elevated troponin I on the previous generation assay (STAT TnI-II). Medical records of individuals presenting to the Royal Perth Hospital ED with elevated hs-TnI between 12 November 2013 and 24 December 2013 were retrospectively reviewed. The 99th percentile hs-TnI thresholds were ≥26 ng/L for males and ≥16 ng/L for females. TnI-II assays were performed concomitantly. In total, 1449 individuals [855 (59%) males] had 3580 troponin measurements. hs-TnI was elevated in 1569 (43.8%) measurements. Elevated hs-TnI with normal TnI-II was found in 120 (8.3%) individuals: 77 (64%) females and 43 (36%) males. Eight (6.7%) individuals were diagnosed with acute coronary syndrome (ACS): four (9.3%) males and four (5.2%) females. Other cardiac aetiologies were found in 33 (42%) females and 17 (40%) males. Individuals with elevated hs-TnI had high rates of hypertension (80%), diabetes mellitus (33%), cardiac failure (23%), aspirin use (53%) and lipid lowering therapy (52%). Significantly fewer females than males with discrepant troponin I results had previous ischaemic heart disease. The hsTnI assay identifies 8% more individuals with elevated troponin in an acute setting, with a female predominance (64%). However, only 6.7% of these individuals with multiple cardiovascular risk factors were diagnosed with ACS, a ∼0.5% increase overall. Outcome studies are required to determine if the Australian hs-TnI thresholds are clinically appropriate.

Dynamic high-sensitivity troponin elevations in atrial fibrillation patients might not be associated with significant coronary artery disease

Background

Since the introduction of high-sensitivity troponin assays a greater proportion of atrial fibrillation (AF) patients present with dynamic troponin elevations. We hypothesize that significant coronary artery disease (CAD) causes relative ischemia in the setting of a rapid heart rate resulting in dynamic troponin elevation. The aim of this study was to examine if patients without known CAD who present with AF, tachycardia and dynamic high-sensitivity troponin T (hsTnT) change have an increased risk of cardiac events.

Methods

We retrospectively included AF patients presenting with tachycardia during one year. The primary endpoint was acute coronary syndrome, revascularization or death due to ischemic heart disease during 30 months follow-up.

Results

Five hundred twenty-two patients without known CAD were included, 300 (57%) had normal hsTnT and 49 (9.5%) had dynamic hsTnT elevation. During follow-up 12 (4%) patients with normal hsTnT reached the primary endpoint and a total of 14 (4.7%) patients died. In the group with dynamic hsTnT the results were 4 (8.2%) and 12 (25%) respectively. The age-adjusted hazard ratio (HR) for the primary endpoint in patients with dynamic hsTnT was 1.9 (95% CI: 0.6 to 6.2; p = 0.28) and for all-cause mortality 3.8 (95% CI: 1.7 to 8.5; p = 0.001).

Conclusions

Dynamic hsTnT elevation in connection with AF might not be associated with any major increased risk of coronary events, but indicates increased all-cause mortality.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-017-0601-7) contains supplementary material, which is available to authorized users.

High sensitivity cardiac troponin T in patients not having an acute coronary syndrome: results from the TRAPID-AMI study

PURPOSE

To describe the baseline, 1 hr and delta high sensitivity cardiac troponin (hs-cTnT) values in patients with suspected acute myocardial infarction (AMI) but without a final acute coronary syndrome (ACS) diagnosis.

MATERIALS AND METHODS

hs-cTnT assay for RAPID rule out of acute myocardial infarction (TRAPID-AMI) was a prospective diagnostic trial that enrolled emergency department (ED) patients with suspected AMI. Final patient diagnoses were adjudicated by a clinical events committee and subjects placed in different clinical groups: AMI, unstable angina, non-ACS cardiac, non-cardiac and unknown origin. The baseline, 1 hr and delta hs-cTnT values were analysed in the 902 non-ACS patients.

RESULTS

Amongst the 1282 studied the patient groups were 213 (17%) AMI, 167 (13%) unstable angina, 113 (9%) non-ACS cardiac, 288 (22%) non-cardiac and 501 (39%) unknown origin. The hs-cTnT values in the non-cardiac and unknown origin groups were combined. The median hs-cTnT values (ng/L) were higher (p < 0.001) in the non-ACS cardiac compared to the non-cardiac/unknown origin group at baseline (11.8, <5) and 1 hr (12.3, <5). Their negative predictive values were 0.955 (baseline) and 0.954 (1 hr) for predicting non-ACS cardiac versus non-cardiac/unknown origin diagnoses.

CONCLUSIONS

Hs-cTnT may help predict whether non-ACS ED patients have a final non-ACS cardiac or non-cardiac/unknown origin diagnoses.

[Fast track chest pain pathway in emergency department]

Acute chest pain is a common reason of consultation in the emergency department. The difficulty lies in discriminating patients with acute coronary syndrome or other life-threatening conditions from those non-cardiovascular, non-life-threatening chest pain. Only 15 to 25 % of patients with acute chest pain actually have acute coronary syndrome. Algorithms using high sensitivity troponin at admission and a second assessment 1 or 3hours later are validated to "rule in" or "rule out" the diagnosis of non ST-elevation myocardial infarction. This may reduce the delay for the diagnosis translating into shorter stay in the emergency department. Those algorithms must be interpreted in the context of clinical and ECG criteria.

Troponin in Cardiovascular Disease Prevention: Updates and Future Direction

Cardiac troponin has been well described as the preferred biomarker for diagnosis of myocardial infarction due to the high sensitivity and specificity for myocardial injury. Numerous other conditions apart from acute coronary syndrome can also lead to small elevations in troponin levels. However, the use of cTn as prognostic biomarker for the primary assessment of cardiovascular risk in asymptomatic patient has only recently been described. And with the development of newer generations of high-sensitivity cardiac troponin assays that can detect 10-fold lower concentrations of troponin, the potential value cTn in the prevention and management of asymptomatic cardiovascular disease has come to the fore. This review provides an overview of the transition of cardiac troponin as a marker of acute myocardial injury to one that detects sub-clinical injury. Evidence continues to show that high-sensitivity troponin is emerging as one of the most powerful prognostic biomarkers for the assessment of cardiovascular risk in the general population.

Increasing specificity of high-sensitivity troponin: new approaches and perspectives in the diagnosis of acute coronary syndromes

In the past years, new generations of assays to detect cardiac troponin (cTn), called sensitive or high sensitivity troponin (hs-Tn), have been introduced. Progressive improvement in the analytical sensitivity of cTn assays has led to a more rapid diagnosis of acute myocardial infarction (AMI) and improved risk stratification in patients with non ST-elevation acute coronary syndromes (NSTE-ACS) but, at the same time, has introduced the problem of a lower diagnostic specificity. As a matter of fact, hs-Tn assays are able to detect very small increases in the biomarker concentration and therefore result "positive" in a wide range of non-ischemic clinical conditions, acute and chronic, cardiac and extra-cardiac. The reduced specificity of hs-Tn versus the previous generation cTn assays may, therefore, lead to an increased number of inappropriate hospitalizations, i.e. patients with high cTn due to no-ACS conditions, and requires a more careful evaluation, not only on the clinical side, but also on the information that hs-Tn assessment may provide. Several approaches to increase this specificity have been used, but the most promising appear to be the "delta approach", which tries to quantify the relative or absolute change in cTn concentration, and the "age approach", which highlights the need for a different cutoff with a better diagnostic efficiency in the elderly population, often affected by other conditions, different from ACS, that can cause an increased level of cTn.