High-Sensitivity Cardiac Troponin T for Early Prediction of Evolving Non–ST-Segment Elevation Myocardial Infarction in Patients with Suspected Acute Coronary Syndrome and Negative Troponin Results on Admission

Cardiac biomarkers are associated with increased risks of adverse clinical outcomes after ischemic stroke

BACKGROUND

Impaired cardiac function was suggested to be implicated in the functional recovery after ischemic stroke, but the prognostic value of cardiac biomarkers among ischemic stroke patients remains unclear. We aimed to prospectively explore the associations of serum lactate dehydrogenase (LDH), plasma N-terminal pro-brain natriuretic peptide (NT-proBNP), and plasma high-sensitivity cardiac troponin T (hs-cTnT) with adverse clinical outcomes after ischemic stroke in a large-scale cohort study.

METHODS

We measured serum LDH, plasma NT-proBNP, and plasma hs-cTnT levels at baseline among 5056 ischemic stroke patients from the Minhang Stroke Cohort study. All patients were followed up at 3 months after ischemic stroke onset. The primary outcome was composite outcome of death and major disability (modified Rankin Scale [mRS] score ≥ 3) at 3 months after stroke onset, and secondary outcomes included death and ordered 7-level categorical score of the mRS.

RESULTS

During 3 months of follow-up, 1584 patients developed the primary outcome. Baseline serum LDH, plasma NT-proBNP, and plasma hs-cTnT were positively associated with the risk of adverse outcomes after ischemic stroke. The multivariable-adjusted odds ratios of primary outcome for the highest versus lowest quartile of LDH, NT-proBNP, and hs-cTnT were 1.37 (95% CI 1.13-1.66; Ptrend = 0.001), 2.51 (95% CI, 2.00-3.16; Ptrend < 0.001), and 2.24 (95% CI 1.77-2.83; Ptrend < 0.001), respectively. Each SD increase of log-transformed cardiac biomarker score was associated with a 49% (95% CI 37-62%; P < 0.001) increased risk of primary outcome. Multivariable-adjusted spline regression analyses showed linear relationships between cardiac biomarkers and the risk of primary outcome (all P for linearity < 0.001). Moreover, adding LDH, NT-proBNP, hs-cTnT, or cardiac biomarker score to conventional risk factors significantly improved the risk reclassification of primary outcome after ischemic stroke (all P < 0.05).

CONCLUSION

High LDH, NT-proBNP, hs-cTnT, and cardiac biomarker score were independently associated with increased risks of adverse clinical outcomes among ischemic stroke patients, suggesting that cardiac biomarkers might be potential prognostic biomarkers for ischemic stroke.

Combining anatomical and biochemical markers in the detection and risk stratification of coronary artery disease

AIMS

We aimed to test the hypothesis if combining coronary artery calcium score (Ca-score) as a quantitative anatomical marker of coronary atherosclerosis with high-sensitivity cardiac troponin as a quantitative biochemical marker of myocardial injury provided incremental value in the detection of functionally relevant coronary artery disease (fCAD) and risk stratification.

METHODS AND RESULTS

Consecutive patients undergoing myocardial perfusion single-photon emission computed tomography (MPS) without prior CAD were enrolled. The diagnosis of fCAD was based on the presence of ischaemia on MPS and coronary angiography; fCAD was centrally adjudicated in the diagnostic and prognostic domain. Diagnostic accuracy was evaluated using the area under the receiver-operating characteristic curve (AUC). The composite of cardiovascular death and non-fatal acute myocardial infarction (AMI) within 730 days was the primary prognostic endpoint. Among 1715 patients eligible for the diagnostic analysis, 399 patients had fCAD. The combination of Ca-score and high-sensitivity cardiac troponin T (hs-cTnT) had good diagnostic accuracy for the diagnosis of fCAD (AUC 0.79, 95% confidence interval (CI) 0.77-0.81), but no incremental value compared with the Ca-score alone (AUC 0.79, 95% CI 0.77-0.81, P = 0.965). Similar results were observed using high-sensitivity cardiac troponin I (AUC 0.80, 95% CI 0.77-0.82) instead of hs-cTnT. Among 1709 patients (99.7%) with available follow-up, 59 patients (3.5%) suffered the composite primary prognostic endpoint (non-fatal AMI, n = 34; CV death, n = 28). Both Ca-score and hs-cTnT had independent prognostic value. Increased risk was restricted to patients with elevation in both markers.

CONCLUSION

The combination of the Ca-score with hs-cTnT increases the prognostic accuracy for future events but does not provide incremental value vs. the Ca-score alone for the diagnosis of fCAD.

STUDY REGISTRATION

Clinical trial registration: NCT00470587.

Safety and feasibility of triage and rapid discharge of patients with chest pain from emergency room: a pragmatic, randomised non-inferiority control trial of the European Society of Cardiology (ESC) 0-1 hour pathway vs. conventional 0-3 hour accelerated diagnostic protocol

Patients presenting with chest pain represent a significant proportion of Emergency Department (ED) attendances but only a minority, typically 10%, have a final diagnosis of myocardial infarction (MI). Prompt discharge of patients without MI will alleviate ED overcrowding as well as improve patient satisfaction and reduce exposure to risk of hospital acquired infections such as Covid 19. The measurement of cardiac troponin (cTn) by a high sensitivity method is recommended by the National Institute for health and Care Excellence (NICE) for rapid categorisation of patients presenting with chest pain. Strategies proposed include measurement on admission and one hour from admission (ESC 0-1-hour pathway, the recent guideline approved pathway which has not been implemented widely), and measurement on admission and three hours from admission (0-3-hour pathway, which is conventional and widely adopted). The primary objective of this study is twofold: firstly, to assess the safety, feasibility, and impact of implementing the ESC (European Society of Cardiology) 0-1-hour pathway in clinical practice by reference to the more established ESC 0-3-hour protocol. The principal outcome measure will be the safety of the ESC 0-1-hour protocol. However, there are concerns that the time from sample draw to result availability (typically around 60 minutes) will impact on the feasibility of the ESC 0-1-hour pathway. Secondly, therefore, our goal is to evaluate whether measurement of high sensitivity troponin by a bedside analyser (point of care testing, POCT), which will produce results in 15 minutes is a feasible alternative to laboratory testing. We will compare the results produced by POCT with the laboratory results in the context of the ESC 0-1 hour and 0-3-hour pathway, as a nested controlled study in the context of a randomised controlled trial. (clinicaltrials.gov: NCT05322395).

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.

Diagnostic and prognostic value of cardiac troponins in emergency department patients presenting after a fall: A prospective, multicenter study

BACKGROUND

Emergency department (ED) presentations after a ground-level fall (GLF) are common. Falls were suggested to be another possible presenting feature of a myocardial infarction (MI), as unrecognized MIs are common in older adults. Elevated high-sensitivity cardiac troponin (hs-cTn) concentrations could help determine the etiology of a GLF in ED. We investigated the prevalence of both MI and elevated high-sensitivity cardiac troponin T (hs-cTnT) and I (hs-cTnI), as well as the diagnostic accuracy of hs-cTnT and hs-cTnI regarding MI, and their prognostic value in older ED patients presenting after a GLF.

METHODS

This was a prospective, international, multicenter, cohort study with a follow-up of up to 1 year. Patients aged 65 years or older presenting to the ED after a GLF were prospectively enrolled. Two outcome assessors independently reviewed all discharge records to ascertain final gold standard diagnoses. Hs-cTnT and hs-cTnI levels were determined from thawed samples for every patient.

RESULTS

In total, 558 patients were included. Median (IQR) age was 83 (77-89) years, and 67.7% were female. Elevated hs-cTnT levels were found in 384 (68.8%) patients, and elevated hs-cTnI levels in 86 (15.4%) patients. Three patients (0.5%) were ascertained the gold standard diagnosis MI. Within 30 days, 18 (3.2%) patients had died. Nonsurvivors had higher hs-cTnT and hs-cTnI levels compared with survivors (hs-cTnT 40 [23-85] ng/L in nonsurvivors and 20 [13-33] ng/L in survivors; hs-cTnI 25 [14-54] ng/L in nonsurvivors and 8 [4-16] ng/L in survivors; p < 0.001 for both).

CONCLUSIONS

A majority of patients (n = 364, 68.8%) presenting to the ED after a fall had elevated hs-cTnT levels and 86 (15.4%) elevated hs-cTnI levels. However, the incidence of MI in these patients was low (n = 3, 0.5%). Our data do not support the opinion that falls may be a common presenting feature of MI. We discourage routine troponin testing in this population. However, hs-cTnT and hs-cTnI were both found to have prognostic properties for mortality prediction up to 1 year.

Diagnostic and prognostic value of the sex-specific 99th percentile of four high-sensitivity cardiac troponin assays in patients with suspected myocardial infarction

AIMS

High-sensitivity cardiac troponin (hs-cTn) assays are used for detection of myocardial infarction (MI). Ninety-ninth percentiles show wide inter-assay variation. The use of sex-specific cut-offs is recommended as definitory cut-off for MI. We compared diagnostic performance and prognostic value of sex-specific 99th percentiles of four hs-cTn assays in patients with suspected MI.

METHODS AND RESULTS

Concentrations of four hs-cTn assays were measured at presentation and after 3 h in patients with suspected MI. Final diagnoses were adjudicated according to the 4th Universal Definition of MI. Unisex and sex-specific 99th percentiles were evaluated as diagnostic cut-offs following the ESC 0/3 h algorithm. These cut-offs were used in Cox-regression analyses to investigate the association with a composite endpoint of MI, revascularization, cardiac rehospitalization, and death. Non-ST-elevation MI was diagnosed in 368 of 2718 patients. Applying the unisex 99th percentile, Elecsys hs-cTnT provided highest negative predictive value (NPV) of 99.7 and a positive predictive value (PPV) of 75.9. The analysed hs-cTnI assays showed slightly lower NPVs and comparable PPVs [Architect (NPV 98.0, PPV of 71.4); Atellica (NPV 97.7, PPV of 76.1); Pathfast (NPV 97.7, PPV of 66.6)]. Application of sex-specific 99th percentiles did not significantly affect diagnostic performance. Concentrations above 99th percentile were independent predictors for impaired long-term outcome (hazard ratios 1.2-1.5, P < 0.001).

CONCLUSION

We describe a good diagnostic accuracy of four hs-cTn assays using the assay-specific 99th percentile for detection of MI. Application of sex-specific 99th percentiles did neither affect diagnostic performance nor prognostic value significantly. Finally, values above the 99th percentile were associated with poor long-term outcome.

Establishing optimal cutoff values for high-sensitivity cardiac troponin algorithms in risk stratification of acute myocardial infarction

Acute myocardial infarction (AMI) is a leading cause of mortality globally, highlighting the need for timely and accurate diagnostic strategies. Cardiac troponin has been the biomarker of choice for detecting myocardial injury. A dynamic change in concentrations supports the diagnosis of AMI in the setting of evidence of acute myocardial ischemia. The new generation of high-sensitivity cardiac troponin (hs-cTn) assays has significantly improved analytical sensitivity but at the expense of decreased clinical specificity. As a result, sophisticated algorithms are required to differentiate AMI from non-AMI patients. Establishing optimal hs-cTn cutoffs for these algorithms to rule out and rule in AMI has been the subject of intensive investigations. These efforts have evolved from examining the utility of the hs-cTn 99th percentile upper reference limit, comparing the percentage versus absolute delta thresholds, and evaluating the performance of an early European Society of Cardiology-recommended 3 h algorithm, to the development of accelerated 1 h and 2 h algorithms that combine the admission hs-cTn concentrations and absolute delta cutoffs to rule out and rule in AMI. Specific cutoffs for individual confounding factors such as sex, age, and renal insufficiency have also been investigated. At the same time, concerns such as whether the small delta thresholds exceed the analytical and biological variations of hs-cTn assays and whether the algorithms developed in European study populations fit all other patient cohorts have been raised. In addition, the accelerated algorithms leave a substantial number of patients in a non-diagnostic observation zone. How to properly diagnose patients falling in this zone and those presenting with elevated baseline hs-cTn concentrations due to the presence of confounding factors or comorbidities remain open questions. Here we discuss the developments described above, focusing on criteria and underlying considerations for establishing optimal cutoffs. In-depth analyses are provided on the influence of biological variation, analytical imprecision, local AMI rate, and the timing of presentation on the performance metrics of the accelerated hs-cTn algorithms. Developing diagnostic strategies for patients who remain in the observation zone and those presenting with confounding factors are also reviewed.

Implementation of the European Society of Cardiology 0/3-hour accelerated diagnostic protocol, using high sensitive troponin T: a clinical practice evaluation of safety and effectiveness involving 3003 patients with suspected acute coronary syndrome

BACKGROUND

There have been relatively few studies detailing the real-world effectiveness and safety of accelerated diagnostic protocols (ADP), using high sensitivity cardiac troponin (hs-cTn).

OBJECTIVE

To analyse the safety and effectiveness of early emergency department (ED) discharge following implementation of the European Society of Cardiology (ESC) 0/3-hour ADP for suspected acute coronary syndromes (ACS).

METHOD

We prospectively studied 2 cohorts of consecutive suspected ACS presentations to ED before (n=1642) and after (n=1376, 2 centres) implementation of the ESC 0/3-hour ADP incorporating limit of detection rule out. Safety was defined by MACE (major adverse cardiac events) inclusive of type 1 myocardial infarction (MI) in patients discharged from ED, and clinical effectiveness by percentage ED discharge. Continuous variables and categorical data were evaluated by independent t-test and χ2 test, respectively. Time-to-event data were analysed as survival data and converted to Kaplan-Meier curves for interpretation.

RESULTS

In the preimplementation period, there was a higher prevalence of MI. Discharge from ED increased by >100% (from 27.1% to 56.5% of the cohort) with no safety signal (MACE rate 4/444 (0.9%) vs 4/769 (0.52%), p=0.430 for the 2011 and 2018 cohort, respectively). This correlated with a marked reduction in length of stay overall but a more modest reduction for those discharged from ED (6 hours 10 min vs 5 hours 25 min, p<0.001) for the 2011 and 2018 cohort, respectively. There were improvements in presentation to blood draw (163-90 min, p<0.001). Time from presentation to first ECG actually increased (16.2 vs 31.2 min, p<0.001). Analysis of hs-cTn values and ECGs revealed a maximum ED discharge rate of 69%, by applying the 0/3-hour protocol, implying potential for increasing safe ED discharge.

CONCLUSIONS

Implementation of an ADP with hs-cTn is safe and effective for early rule-out and discharge of suspected ACS but require considerable resources and education to optimise maximal patient flow.

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.

Using historical cardiac troponins to identify patients at a high risk of myocardial infarction

OBJECTIVE

Many patients who present with chest pain have previous measurements of high-sensitivity cardiac troponin T (hs-cTnT). The clinical usefulness of incorporating these measurements in identifying patients who are at a high risk of myocardial infarction (MI) is unknown. We investigated if the relative change between a historical hs-cTnT and the admission hs-cTnT could improve early identification of patients with a high risk of MI.

METHODS

We included all patients presenting with chest pain to seven different emergency departments (EDs) in Sweden from December 2009 to December 2016, who had at least one hs-cTnT measurement at the presentation and at least one available prior measurement. We used logistic regression to investigate the diagnostic performance of using various combinations of current and historical hs-cTnT measurements in diagnosing MI within 30 days.

RESULTS

A total of 27 809 visits were included, among whom 2686 (9.7%) had an MI within 30 days. A cut-off value for historical hs-cTnT-adjusted admission hs-cTnT with similar specificity (91.2%) as an admission hs-cTnT of ≥52 ng/L identified 4% more MIs (43% vs 39%) and had a higher positive predictive value, 42.6% (95% CI, 41.0% to 44.3%) vs 38.9% (95% CI 37.4% to 40.4%), as well as a higher positive likelihood ratio, 6.95 (95% CI 6.69 to 7.22) vs 5.95 (95% CI 5.73 to 6.18). Among patients with an admission hs-cTnT of <52 ng/L who were classified as high-risk patients when incorporating past hs-cTnT measurements, 28% suffered an MI.

CONCLUSIONS

Historical hs-cTnT levels can be used with admission hs-cTnT to improve early risk stratification of MI in the ED.

ECG and Biomarker Profile in Patients with Acute Heart Failure: A Pilot Study

Background: Biomarkers, electrocardiogram (ECG) and Holter ECG are basic, accessible and feasible cardiac investigations. The combination of their results may lead to a more complex predictive model that may improve the clinical approach in acute heart failure (AHF). The main objective was to investigate which ECG parameters are correlated with the usual cardiac biomarkers (prohormone N-terminal proBNP, high-sensitive cardiac troponin I) in patients with acute heart failure, in a population from Romania. The relationship between certain ECG parameters and cardiac biomarkers may support future research on their combined prognostic value. Methods: In this prospective case-control study were included 49 patients with acute heart failure and 31 participants in the control group. For all patients we measured levels of prohormone N-terminal proBNP (NT-proBNP), high-sensitive cardiac troponin I (hs-cTnI) and MB isoenzyme of creatine phosphokinase (CK-MB) and evaluated the 12-lead ECG and 24 h Holter monitoring. Complete clinical and paraclinical evaluation was performed. Results: NT-proBNP level was significantly higher in patients with AHF (p < 0.001). In patients with AHF, NT-proBNP correlated with cQTi (p = 0.027), pathological Q wave (p = 0.029), complex premature ventricular contractions (PVCs) (p = 0.034) and ventricular tachycardia (p = 0.048). Hs-cTnI and CK-MB were correlated with ST-segment modification (p = 0.038; p = 0.018) and hs-cTnI alone with complex PVCs (p = 0.031). Conclusions: The statistical relationships found between cardiac biomarkers and ECG patterns support the added value of ECG in the diagnosis of AHF. We emphasize the importance of proper ECG analysis of more subtle parameters that can easily be missed. As a non-invasive technique, ECG can be used in the outpatient setting as a warning signal, announcing the acute decompensation of HF. In addition, the information provided by the ECG complements the biomarker results, supporting the diagnosis of AHF in cases of dyspnea of uncertain etiology. Further studies are needed to confirm long-term prognosis in a multi-marker approach.

High-Sensitivity Cardiac Troponin T and the Diagnosis of Cardiovascular Disease in the Emergency Room: The Importance of Combining Cardiovascular Biomarkers with Clinical Data

Background. Nowadays, it is still not possible to clinically distinguish whether an increase in high-sensitivity cardiac troponin (hs-cTn) values is due to myocardial injury or an acute coronary syndrome (ACS). Moreover, predictive data regarding hs-cTnT in an emergency room (ER) setting are scarce. This monocentric retrospective study aimed to improve the knowledge and interpretation of this cardiac biomarker in daily clinical practice. Methods. Consecutive adult patients presenting at the ER and hospitalized with a first abnormal hs-cTnT value (≥14 ng/L) were enrolled for 6 months. The baseline hs-cTnT value and the ensuing changes and variations were correlated with the clinical presentation and the type of diagnosis. Subsequently, multivariable models were built to assess which clinical/laboratory variables most influenced hospital admissions in the investigated population analyzed according to the final reason for hospitalization: (1) cardiovascular vs. non-cardiovascular diagnosis, and (2) ACS vs. non-ACS one. Results. A total of 4660 patients were considered, and, after a first screening, 4149 patients were enrolled. Out of 4129 patients, 1555 (37.5%) had a first hs-cTnT ≥14 ng/L, and 1007 (65%) were hospitalized with the following types of diagnosis: ACS (182; 18%), non-ACS cardiovascular disease (337; 34%) and non-cardiovascular disease (487; 48%). Higher hs-cTnT values and significant hs-cTnT variations were found in the ACS group (p < 0.01). The mean percentage of variation was higher in patients with ACS, intermediate in those with non-ACS cardiovascular disease, and low in those with non-cardiovascular disease (407.5%, 270.6% and 12.4%, respectively). Only syncope and CRP (OR: 0.08, 95% CI: 0.02−0.39, p < 0.01 and OR: 0.9988, 95% CI: 0.9979−0.9998, p = 0.02, respectively) or CRP (OR: 0.9948, 95% CI: 0.9908−0.9989, p = 0.01) and NT-proBNP (OR: 1.0002, 95% CI: 1.0000−1.0004, p = 0.02) were independent predictors of a cardiovascular disease diagnosis. On the other hand, only chest pain (OR: 22.91, 95% CI: 3.97−132.32, p < 0.01) and eGFR (OR: 1.04, 95% CI: 1.004−1.083, p = 0.03) were associated with the ACS diagnosis. Conclusions. Differently from the investigated biomarkers, in this study, only clinical variables predicted hospitalizations in different patients’ subgroups.

Troponin I Cutoff for Non-ST-Segment Elevation Myocardial Infarction in Sepsis

The diagnostic value and optimal cutoff level of cardiac troponin I in patients with sepsis have not been studied. In this single hospital retrospective study, we assessed the optimal cutoff value of troponin I for diagnosing non-ST-segment elevation myocardial infarction (NSTEMI) with type 1 myocardial infarction (MI) in patients with sepsis who had undergone a percutaneous coronary intervention from 2009 to 2019. In total, 5,341 patients (excluding patients with chronic kidney disease) were included, of whom 277 had sepsis or septic shock. Of the 123 patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) and sepsis, 77 (62.6%) were diagnosed with NSTEMI with type 1 MI. The receiver-operating characteristic curve showed an area under the curve (AUC) of 0.705 for diagnosis of NSTEMI with type 1 MI with a troponin I cutoff of >300 ng/L (sensitivity: 68.4%, specificity: 70.2%, Youden index: 0.386). Multiple linear regression showed no significant predictors of NSTEMI with type 1 MI. Troponin level and the Global Registry of Acute Coronary Events (GRACE) scores were correlated (R² = 0.0625, p = 0.032) and showed comparable predictive value for 6-month mortality (AUC: 0.637 and 0.611, respectively, p = 0.7651). The optimal troponin I cutoff to effectively diagnose NSTEMI with type 1 MI in patients with sepsis was 300 ng/L.

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.

Adding historical high-sensitivity troponin T results to rule out acute myocardial infarction

AIMS

The clinical usefulness of historical concentrations of high-sensitivity cardiac troponin T (hs-cTnT) is unknown. This study investigated the ability to rule out myocardial infarction (MI) with the use of historical hs-cTnT concentrations among patients with chest pain in the emergency department (ED).

METHODS AND RESULTS

The derivation cohort consisted of patients presenting with chest pain to nine different EDs (n = 60 071), where we included those with ≥1 hs-cTnT analysed at the index visit and ≥1 hs-cTnT results prior to the visit. We developed an algorithm to rule out MI within 30 days with a pre-specified target negative predictive value (NPV) of ≥99.5%. The performance was then validated in a separate cohort of ED chest pain patients (n = 10 994). A historical hs-cTnT < 12 ng/L and a < 3 ng/L absolute change between the historical and the index visit hs-cTnT had the best performance and ruled out 24 862 (41%) patients in the derivation cohort. In the validation cohort, these criteria identified 4764 (43%) low-risk patients in whom 18 (0.4%) MIs within 30 days occurred, and had an NPV for MI of 99.6% (99.4-99.8), a sensitivity of 96.9% (95.2-.2), and an LR- of 0.11 (0.07-0.14).

CONCLUSION

Combining a historical hs-cTnT with a single new hs-cTnT may safely rule out MI and thereby reduce the need for serial hs-cTnT measurements in ED patients with chest pain.

Gut microbiota-dependent metabolite trimethylamine N-oxide (TMAO) and cardiovascular risk in patients with suspected functionally relevant coronary artery disease (fCAD)

BACKGROUND

Trimethylamine N-oxide (TMAO) has been associated with cardiovascular outcomes. However, the diagnostic value of TMAO and its precursors have not been assessed for functionally relevant coronary artery disease (fCAD) and its prognostic potential in this setting needs to be evaluated.

METHODS

Among 1726 patients with suspected fCAD serum TMAO, and its precursors betaine, choline and carnitine, were quantified using liquid chromatography tandem mass spectrometry. Diagnosis of fCAD was performed by myocardial perfusion single photon emission tomography (MPI-SPECT) and coronary angiography blinded to marker concentrations. Incident all-cause death, cardiovascular death (CVD) and myocardial infarction (MI) were assessed during 5-years follow-up.

RESULTS

Concentrations of TMAO, betaine, choline and carnitine were significantly higher in patients with fCAD versus those without (TMAO 5.33 μM vs 4.66 μM, p < 0.001); however, diagnostic accuracy was low (TMAO area under the receiver operating curve [AUC]: 0.56, 95% CI [0.53-0.59], p < 0.001). In prognostic analyses, TMAO, choline and carnitine above the median were associated with significantly (p < 0.001 for all) higher cumulative events for death and CVD during 5-years follow-up. TMAO remained a significant predictor for death and CVD even in full models adjusted for renal function (HR = 1.58 (1.16, 2.14), p = 0.003; HR = 1.66 [1.07, 2.59], p = 0.025). Prognostic discriminative accuracy for TMAO was good and robust for death and CVD (2-years AUC for CVD 0.73, 95% CI [0.65-0.80]).

CONCLUSION

TMAO and its precursors, betaine, choline and carnitine were significantly associated with fCAD, but with limited diagnostic value. TMAO was a strong predictor for incident death and CVD in patients with suspected fCAD.

CLINICAL TRIAL REGISTRATION

NCT01838148.

Multimodal assessment of acute cardiac toxicity induced by thoracic radiotherapy in cancer patients. Study protocol

Background

Today, cancer ranks as one of the leading causes of death. Despite the large number of novel available therapies, radiotherapy (RT) remains as the most effective non-surgical method to cure cancer patients. In fact, approximately 50% of all cancer patients receive some type of RT and among these 60% receive RT-treatment with a curative intent. However, as occurs with any other oncological therapy, RT treated patients may experience toxicity side effects that range from moderate to severe. Among these, cardiotoxicity represents a significant threat for premature death. Current methods evaluate cardiotoxic damage based on volumetric changes in the Left Ventricle Ejected Fraction (LVEF). Indeed, a 10% drop in LVEF is commonly used as indicator of cardiotoxicity. More recently, a number of novel techniques have been developed that significantly improve specificity and sensitivity of heart’s volumetric changes and early detection of cardiotoxicity even in asymptomatic patients. Among these, the Strain by Speckle Tracking (SST) is a technique based on echocardiographic analysis that accurately evaluates myocardial deformation during the cardiac cycle (ventricular and atrial function). Studies also suggest that Magnetic Resonance Imaging (MRI) is a high-resolution technique that enables a better visualization of acute cardiac damage.

Methodology

This protocol will evaluate changes in SST and MRI in cancer patients that received thoracic RT. Concomitantly, we will assess changes in serum biomarkers of cardiac damage in these patients, including: high-sensitivity cardiac Troponin-T (hscTnT), N-Terminal pro-Brain Natriuretic Peptide (NTproBNP) and Circulating Endothelial Cells (CECs), a marker of endothelial dysfunction and vascular damage.

Discussion

The presented protocol is to our knowledge the first to prospectively and with a multimodal approach, study serological and image biomarkers off early cardiac damage due to radiotherapy.

With a practical clinical approach we will seek early changes that could potentially be in the future be linked to clinical mayor events with consequences for cancer survivors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08823-3.

High-sensitivity troponin assays for early rule-out of acute myocardial infarction in people with acute chest pain: a systematic review and economic evaluation

BACKGROUND

Early diagnosis of acute myocardial infarction is important, but only 20% of emergency admissions for chest pain will actually have an acute myocardial infarction. High-sensitivity cardiac troponin assays may allow rapid rule out of myocardial infarction and avoid unnecessary hospital admissions.

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of high-sensitivity cardiac troponin assays for the management of adults presenting with acute chest pain, in particular for the early rule-out of acute myocardial infarction.

METHODS

Sixteen databases were searched up to September 2019. Review methods followed published guidelines. Studies were assessed for quality using appropriate risk-of-bias tools. The bivariate model was used to estimate summary sensitivity and specificity for meta-analyses involving four or more studies; otherwise, random-effects logistic regression was used. The health economic analysis considered the long-term costs and quality-adjusted life-years associated with different troponin testing methods. The de novo model consisted of a decision tree and a state-transition cohort model. A lifetime time horizon (of 60 years) was used.

RESULTS

Thirty-seven studies (123 publications) were included in the review. The high-sensitivity cardiac troponin test strategies evaluated are defined by the combination of four factors (i.e. assay, number and timing of tests, and threshold concentration), resulting in a large number of possible combinations. Clinical opinion indicated a minimum clinically acceptable sensitivity of 97%. When considering single test strategies, only those using a threshold at or near to the limit of detection for the assay, in a sample taken at presentation, met the minimum clinically acceptable sensitivity criterion. The majority of the multiple test strategies that met this criterion comprised an initial rule-out step, based on high-sensitivity cardiac troponin levels in a sample taken on presentation and a minimum symptom duration, and a second stage for patients not meeting the initial rule-out criteria, based on presentation levels of high-sensitivity cardiac troponin and absolute change after 1, 2 or 3 hours. Two large cluster randomised controlled trials found that implementation of an early rule-out pathway for myocardial infarction reduced length of stay and rate of hospital admission without increasing cardiac events. In the base-case analysis, standard troponin testing was both the most effective and the most costly. Other testing strategies with a sensitivity of 100% (subject to uncertainty) were almost equally effective, resulting in the same life-year and quality-adjusted life-year gain at up to four decimal places. Comparisons based on the next best alternative showed that for willingness-to-pay values below £8455 per quality-adjusted life-year, the Access High Sensitivity Troponin I (Beckman Coulter, Brea, CA, USA) [(symptoms > 3 hours AND < 4 ng/l at 0 hours) OR (< 5 ng/l AND Δ < 5 ng/l at 0 to 2 hours)] would be cost-effective. For thresholds between £8455 and £20,190 per quality-adjusted life-year, the Elecsys® Troponin-T high sensitive (Roche, Basel, Switzerland) (< 12 ng/l at 0 hours AND Δ < 3 ng/l at 0 to 1 hours) would be cost-effective. For a threshold > £20,190 per quality-adjusted life-year, the Dimension Vista® High-Sensitivity Troponin I (Siemens Healthcare, Erlangen, Germany) (< 5 ng/l at 0 hours AND Δ < 2 ng/l at 0 to 1 hours) would be cost-effective.

CONCLUSIONS

High-sensitivity cardiac troponin testing may be cost-effective compared with standard troponin testing.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42019154716.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Evidence Synthesis programme and will be published in full in Health Technology Assessment; Vol. 25, No. 33. See the NIHR Journals Library website for further project information.

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.

Pre-hospital One-Hour Troponin in a Low-Prevalence Population of Acute Coronary Syndrome: OUT-ACS study

Objective

The European Society of Cardiology 0/1-hour algorithm for high-sensitivity cardiac troponin T (hs-cTnT) has demonstrated high rule-out safety in large hospital validation cohorts. We aimed to validate the algorithm in a primary care setting, where patients have a lower pretest probability for acute coronary syndrome.

Methods

This prospective, observational, diagnostic study included patients with acute non-specific chest pain admitted to a primary care emergency clinic in Oslo, Norway, from November 2016 to October 2018. hs-cTnT was measured after 0, 1 and 4 hours. The primary outcome measure was the diagnostic performance of the 0/1-hour algorithm, the 90-day incidence of AMI or all-cause death the secondary.

Results

Among 1711 included patients, 61 (3.6%) were diagnosed with AMI. By applying the algorithm, 1311 (76.6%) patients were assigned to the rule-out group. The negative predictive value was 99.9% (95% CI 99.5% to 100.0%), the sensitivity and specificity 98.4% (91.2–100.0) and 79.4% (77.4–81.3), respectively. Sixty-six (3.9%) patients were triaged towards rule-in, where 45 were diagnosed with AMI. The corresponding positive predictive value was 68.2% (58.3–76.7), sensitivity 73.8% (60.9–84.2), and specificity 98.7% (98.1–99.2). Among 334 (19.5%) patients assigned to the observation group in need of further tests, 15 patients had an AMI. The following 90 days, five new patients experienced an AMI and nine patients died, with a low incidence in the rule-out group (0.3%).

Conclusion

The 0/1-hour algorithm for hs-cTnT seems safe, efficient and applicable for an accelerated assessment of patients with non-specific chest pain in a primary care emergency setting.

Trial registration number

NCT02983123.

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.'

Fast 0/1-h algorithm for detection of NSTEMI: are current high-sensitivity cardiac troponin assays fit for purpose? An EQA-based evaluation

Background High-sensitivity cardiac troponin T/I (hs-cTnT/I) assays have improved analytical sensitivity for the detection of myocardial infarction (MI). To gain clinical specificity and sensitivity, interpretation of changes in cTn concentrations over time is crucial. The 2015 ESC NSTEMI guideline defines absolute delta values as additional rule-in and rule-out criteria for MI. A critical assumption for application of this rule is that total analytical imprecision within the delta period, including inter-instrument bias, is comparable to analytical imprecision in the validation studies. Methods Data from the Dutch External Quality Assessment Scheme (EQAS) were used to calculate inter-instrument bias and estimate imprecision for the measuring range where the proposed delta values are relevant: for Roche Elecsys hs-cTnT, 5-52 and 5-12 ng/L; for Abbott Architect hs-cTnI, 2-52 and 2-5 ng/L for rule-in and rule-out, respectively. Results For Elecsys, the median inter-instrument bias is 0.3 ng/L (n = 33 laboratories), resulting in reference change values (RCVs) of 3.0 and 1.7 ng/L, respectively, for rule-in and rule-out with imprecision as claimed by the manufacturer. With RCVs smaller than the guideline's delta thresholds, 100% of the laboratories have adequate specifications. RCVs for rule-in/rule-out increased to 4.6 ng/L/2.5 ng/L, respectively, with individual imprecisions as estimated from EQA data, resulting in 64% and 82% of laboratories with adequate specifications. For Architect, 40% of instruments (n = 10) might falsely qualify the result as clinically relevant; hence, inter-instrument bias could not be determined. Conclusions We advise laboratories that use the fast 0/1-h algorithm to introduce stringent internal quality procedures at the relevant/low concentration level, especially when multiple analyzers are randomly used.

Effect of Lentivirus-Mediated miR-499a-3p on Human Umbilical Vein Endothelial Cells

Objective

To explore the possible role of miR-499a-3p in the function of primary human umbilical vein endothelial cells (HUVECs) and the expression of ADAM10 in primary HUVEC.

Method

miR-499a-3p was first transfected into primary HUVECs via lentivirus vector. The viability, proliferation, and migration of stable transfected primary HUVEC were then determined by flow cytometry, CCK8 assays, scratch tests, and Transwell tests. The transcription of miR-499a-3p and ADAM10 was examined by reverse transcription-polymerase chain reaction (RT-PCR), and the expression of ADAM10 was examined by Western blot (WB).

Results

After transfection, miR-499a-3p transcription was significantly increased (P < 0.01), compared to the blank and nonspecific control (NC) groups, while both ADAM10 transcription and expression were significantly decreased (P < 0.05). In contrast, in the inhibitors group, miR-499a-3p transcription was significantly reduced (P < 0.05) whereas both ADAM10 transcription and expression were significantly increased (P < 0.05). The viability, proliferation, and migration of primary HUVECs were significantly impaired (P < 0.05) by the transfection of miR-499a-3p but enhanced by miR-499a-3p inhibitors (P < 0.05).

Conclusions

Upregulation of miR-499a-3p transcription will inhibit the expression of ADAM10 in HUVECs; cell migration and proliferation, however, promote apoptosis. And reverse effects were established by downregulation of miR-499a-3p transcription. All these effects may be achieved by regulating the transcription and expression of ADAM10. These results combined suggested that miR-499a-3p may affect the proliferation, migration, and apoptosis of endothelial cells and regulate AS by regulating ADAM10. miR-499a-3p may become a candidate biomarker for the diagnosis of unstable angina pectoris (UA).

Performance of the modified HEART score in an Asian population

INTRODUCTION

Chest pain is the most common potentially life-threatening presentation to the emergency department (ED). Furthermore, the identification of acute coronary syndrome (ACS) including its risk stratification and subsequent disposition can be challenging. The original HEART score was derived as a predictive tool to risk stratify patients presenting with undifferentiated chest pain (CP) and aid physician decision-making. However, it utilized conventional troponins as its cardiac biomarker component. Our study aims to assess the utility of the modified HEART score with highly sensitive troponins in an Asian setting with mixed ethnicity to determine if it corroborates the findings of another recent Chinese study by Chun-Peng et al. (Journal of Geriatric Cardiology 13:64-69, 2016).

METHODS

Clinical data from 413 patients presenting to the ED for evaluation of chest pain were analyzed. The predictive value of the modified HEART score for determining major adverse cardiac events (MACE) was then evaluated.

RESULTS

A total of 49 patients (11.9%) had a MACE: 31 patients (7.5%) underwent PCI and 1 patient (0.2%) underwent CABG. There were 17 (4.1%) deaths. Three risk groups were elucidated based on MACE. In the low-risk group (0-2), there were 72 patients (17.4%), with a MACE rate of 1.4%. In the intermediate-risk group (3-5), there were 233 patients (56.4%), with a MACE rate of 5.2%. In the high-risk group (6-10), there were 108 patients (26.2%), with a MACE rate of 33.3%.

CONCLUSION

The modified HEART score is an effective risk stratification tool in an ethnically diverse Asian population. Furthermore, it identifies low-risk patients who are candidates for early discharge from a local emergency department.

Preoperative neutrophil to lymphocyte ratio and platelet to lymphocyte ratio are associated with major adverse cardiovascular and cerebrovascular events in coronary heart disease patients undergoing non-cardiac surgery

BACKGROUND

Preoperative risk prediction in patients at elevated cardiovascular risk shows limited accuracy. Platelet to lymphocyte ratio (PLR) and neutrophil to lymphocyte ratio (NLR) indicate systemic inflammation. Both have been investigated for outcome prediction in the field of oncology and cardiovascular medicine, as well as risk prediction of adverse cardiovascular events in non-surgical patients at increased cardiovascular risk.

METHODS

For this post-hoc analysis, we included all 38 coronary heart disease patients from the Leukocytes and Cardiovascular Perioperative Events cohort-1 study scheduled for elective non-cardiac surgery. We evaluated preoperative differential blood counts for association with major adverse cardiovascular and cerebrovascular events (MACCE) defined as the composite endpoint of death, myocardial ischemia, myocardial infarction, myocardial injury after non-cardiac surgery, or embolic or thrombotic stroke within 30 days after surgery. We used Youden's index to calculate cut-off values for PLR and NLR. Additive risk-predictive values were assessed using receiver operating characteristic curve and net reclassification (NRI) improvement analyses.

RESULTS

Patients with the composite endpoint MACCE had higher PLR and NLR (309 [206; 380] vs. 160 [132; 203], p = 0.001; 4.9 [3.5; 8.1] vs. 2.6 [2.2; 3.4]), p = 0.001). Calculated cut-offs for PLR > 204.4 and NLR > 3.1 were associated with increased risk of 30-day MACCE (OR 7, 95% CI [1.2; 44.7], p = 0.034; OR 36, 95% CI [1.8; 686.6], p = 0.001). Furthermore, NLR improved risk prediction in coronary heart disease patients undergoing non-cardiac surgery when combined with hs-cTnT or NT-proBNP (NRI _total = 0.23, p = 0.008, NRI _total = 0.26, p = 0.005).

CONCLUSIONS

Both PLR and NLR were associated with perioperative cardiovascular adverse events in coronary heart disease patients. NLR proved to be of additional value for preoperative risk stratification. Both PLR and NLR could be used as inexpensive and broadly available tools for perioperative risk assessment.

TRIAL REGISTRATION

NCT02874508, August 22, 2016.

Sequential Surgical Procedures in Vascular Surgery Patients Are Associated With Perioperative Adverse Cardiac Events

Patients at elevated cardiovascular risk are prone to perioperative cardiovascular complications, like myocardial injury after non-cardiac surgery (MINS). We have demonstrated in a mouse model of atherosclerosis that perioperative stress leads to an increase in plaque volume and higher plaque vulnerability. Regulatory T cells (Tregs) play a pivotal role in development and destabilization of atherosclerotic plaques. For this exploratory post-hoc analysis we identified 40 patients recruited into a prospective perioperative biomarker study, who within the inclusion period underwent sequential open vascular surgery. On the basis of protein markers measured in the biomarker study, we evaluated the perioperative inflammatory response in patients' plasma before and after index surgery as well as before and after a second surgical procedure. We also analyzed available immunohistochemistry samples to describe plaque vulnerability in patients who underwent bilateral carotid endarterectomy (CEA) in two subsequent surgical procedures. Finally, we assessed if MINS was associated with sequential surgery. The inflammatory response of both surgeries was characterized by postoperative increases of interleukin-6,−10, Pentraxin 3 and C-reactive protein with no clear-cut difference between the two time points of surgery. Plaques from CEA extracted during the second surgery contained less Tregs, as measured by Foxp3 staining, than plaques from the first intervention. The 2nd surgical procedure was associated with MINS. In conclusion, we provide descriptive evidence that sequential surgical procedures involve repeat inflammation, and we hypothesize that elevated rates of cardiovascular complications after the second procedure could be related to reduced levels of intraplaque Tregs, a finding that deserves confirmatory testing and mechanistic exploration in future populations.

Using High-Sensitivity Cardiac Troponin for the Exclusion of Inducible Myocardial Ischemia in Symptomatic Patients: A Cohort Study

BACKGROUND

The optimal noninvasive method for surveillance in symptomatic patients with stable coronary artery disease (CAD) is unknown.

OBJECTIVE

To apply a novel approach using very low concentrations of high-sensitivity cardiac troponin I (hs-cTnI) for exclusion of inducible myocardial ischemia in symptomatic patients with CAD.

DESIGN

Prospective diagnostic cohort study. (ClinicalTrials.gov: NCT01838148).

SETTING

University hospital.

PATIENTS

1896 consecutive patients with CAD referred with symptoms possibly related to inducible myocardial ischemia.

MEASUREMENTS

Presence of inducible myocardial ischemia was adjudicated using myocardial perfusion imaging with single-photon emission computed tomography, as well as coronary angiography and fractional flow reserve measurements where available. Staff blinded to adjudication measured circulating hs-cTn concentrations. An hs-cTnI cutoff of 2.5 ng/L, derived previously in mostly asymptomatic patients with CAD, was assessed. Predefined target performance criteria were at least 90% negative predictive value (NPV) and at least 90% sensitivity for exclusion of inducible myocardial ischemia. Sensitivity analyses were based on measurements with an hs-cTnT assay and an alternative hs-cTnI assay with even higher analytic sensitivity (limit of detection, 0.1 ng/L).

RESULTS

Overall, 865 patients (46%) had inducible myocardial ischemia. The hs-cTnI cutoff of 2.5 ng/L provided an NPV of 70% (95% CI, 64% to 75%) and a sensitivity of 90% (CI, 88% to 92%) for exclusion of inducible myocardial ischemia. No hs-cTnI cutoff reached both performance characteristics predefined as targets. Similarly, using the alternative assays for hs-cTnI or hs-cTnT, no cutoff achieved the target performance: hs-cTnT concentrations less than 5 ng/L yielded an NPV of 66% (CI, 59% to 72%), and hs-cTnI concentrations less than 2 ng/L yielded an NPV of 68% (CI, 62% to 74%).

LIMITATION

Data were generated in a large single-center diagnostic study using central adjudication.

CONCLUSION

In symptomatic patients with CAD, very low hs-cTn concentrations, including hs-cTnI concentrations less than 2.5 ng/L, do not generally allow users to safely exclude inducible myocardial ischemia.

PRIMARY FUNDING SOURCE

European Union, Swiss National Science Foundation, Kommission für Technologie und Innovation (Innosuisse), Swiss Heart Foundation, Cardiovascular Research Foundation Basel, University of Basel, University Hospital Basel, Roche, Abbott, and Singulex.

Cardiac Troponins for the Diagnosis of Acute Myocardial Infarction in Chronic Kidney Disease

Background Patients with chronic kidney disease ( CKD ) are at high risk of myocardial infarction. Cardiac troponins are the biomarkers of choice for the diagnosis of acute myocardial infarction ( AMI ) without ST -segment elevation ( NSTE ). In patients with CKD , troponin levels are often chronically elevated, which reduces their diagnostic utility when NSTE - AMI is suspected. The aim of this study was to derive a diagnostic algorithm for serial troponin measurements in patients with CKD and suspected NSTE - AMI . Methods and Results Two cohorts, 1494 patients from a prospective cohort study with high-sensitivity troponin I (hs- cTnI ) measurements and 7059 cases from a clinical registry with high-sensitivity troponin T (hs- cTnT ) measurements, were analyzed. The prospective cohort comprised 280 CKD patients (estimated glomerular filtration rate <60 mL/min/1.73 m²). The registry data set contained 1581 CKD patients. In both cohorts, CKD patients were more likely to have adjudicated NSTE - AMI than non- CKD patients. The specificities of hs- cTnI and hs- cTnT to detect NSTE - AMI were reduced with CKD (0.82 versus 0.91 for hs- cTnI and 0.26 versus 0.73 for hs- cTnT ) but could be restored by applying optimized cutoffs to either the first or a second measurement after 3 hours. The best diagnostic performance was achieved with an algorithm that incorporates serial measurements and rules in or out AMI in 69% (hs- cTnI ) and 55% (hs- cTnT ) of CKD patients. Conclusions The diagnostic performance of high-sensitivity cardiac troponins in patients with CKD with suspected NSTE - AMI is improved by use of an algorithm based on admission troponin and dynamic changes in troponin concentration.

Revisiting the Biological Variability of Cardiac Troponin: Implications for Clinical Practice

The diagnosis of acute myocardial injury requires a rise and/or fall of cardiac troponin (cTn) on serial testing, with at least one concentration above the 99th percentile value of a normal reference population according to the recently published Fourth Universal Definition of Myocardial Infarction.1 However, the magnitude of change in cTn that constitutes a significant rise and/or fall was again not specified in detail. High-sensitivity cardiac troponin (hs-cTn) assays can measure ten-fold lower concentrations of cTn with more precision than older assays, and can accurately quantify cTn in more than 50% of healthy individuals with a coefficient of variation of less than 10% at the 99th percentile. These hs-cTn assays are also able to detect the normal variations in cTn results that are due to biological variability. Understanding and quantifying the normal variations in cTn is important as this would allow significant changes to be better defined. Numerous studies have sought to investigate the biological variability of cTn over the last ten years. Such studies are usually conducted in healthy individuals, however individuals with chronic cardiac disease or chronic renal failure have also been examined. These studies have yielded varying results in regards to significant change values for cTn. In light of the recent redefinition for myocardial infarction, the purpose of this mini-review is to revisit the biological variability of cTn. In particular, we outline concepts for determining a significant change value, review the results of previous studies on the biological variation of cTn and discuss potential considerations for clinical practice.

A comparison of cardiac troponin T delta change methods and the importance of the clinical context in the assessment of acute coronary syndrome

Background

The management of patients presenting with symptoms suggestive of acute coronary syndrome is a significant challenge for clinicians. Guidelines for the diagnosis of acute myocardial infarction require a rise and/or fall of cardiac troponin, along with other criteria. Knowing what constitutes a significant delta change from baseline is still unclear and the literature is varied.

Methods

We compared three methods for determining cardiac troponin delta changes (relative, absolute and z-scores) for detecting acute myocardial infarction in 806 patients presenting to an emergency department with symptoms suggestive of acute coronary syndrome. Blood specimens were collected at admission and 2, 3, 4 and 6 h postadmission and tested on the Roche Elecsys high-sensitivity troponin T assay.

Results

A positive diagnosis for acute myocardial infarction was found in 39 (4.8%) patients. ROC AUC showed better performance for the absolute and z-score delta change (0.959–0.988 and 0.956–0.988, respectively) compared with relative delta change (0.921–0.960) at all time points in the diagnosis of acute myocardial infarction. Optimal timing for the second sample was at 4–6 h postadmission.

Conclusions

Although not statistically significant, the results show a trend of absolute and z-score delta change performing better than relative delta change for the diagnosis of acute myocardial infarction. The z-score approach allows for a single cut-off value across multiple high-sensitivity assays which could be useful in the clinical setting. Our study also highlighted the importance of interpreting cardiac troponin changes in the clinical context with a combination of the patient’s clinical history and electrocardiogram.

Frontline Science: Low regulatory T cells predict perioperative major adverse cardiovascular and cerebrovascular events after noncardiac surgery

Immune cells drive atherosclerotic lesion progression and plaque destabilization. Coronary heart disease patients undergoing noncardiac surgery are at risk for perioperative major adverse cardiac and cerebrovascular events (MACCE). It is unclear whether differential leukocyte subpopulations contribute to perioperative MACCE and thereby could aid identification of patients prone to perioperative cardiovascular events. First, we performed a hypothesis-generating post hoc analysis of the LeukoCAPE-1 study (n = 38). We analyzed preoperative counts of 6 leukocyte subpopulations in coronary heart disease patients for association with MACCE (composite of cardiac death, myocardial infarction, myocardial ischemia, myocardial injury after noncardiac surgery, thromboembolic stroke) within 30 d after surgery. Regulatory T cells (Tregs) were the only leukocyte subgroup associated with MACCE. We found reduced Tregs in patients experiencing MACCE versus no-MACCE (0.02 [0.01; 0.03] vs. 0.04 [0.03; 0.05] Tregs nl^-1 , P = 0.002). Using Youden index, we derived the optimal threshold value for association with MACCE to be 0.027 Tregs nl^-1 . Subsequently, we recruited 233 coronary heart disease patients for the prospective, observational LeukoCAPE-2 study and independently validated this Treg cutoff for prediction of MACCE within 30 d after noncardiac surgery. After multivariate logistic regression, Tregs < 0.027 cells nl^-1 remained an independent predictor for MACCE (OR = 2.54 [1.22; 5.23], P = 0.012). Tregs improved risk discrimination of the revised cardiac risk index based on ΔAUC (area under the curve; ΔAUC = 0.09, P = 0.02), NRI (0.26), and IDI (0.06). Preoperative Treg levels below 0.027 cells nl^-1 predicted perioperative MACCE and can be measured to increase accuracy of established preoperative cardiac risk stratification in coronary heart disease patients undergoing noncardiac surgery.

Prognostic value of high-sensitive troponin T for predicting cardiovascular events after atrial fibrillation ablation

BACKGROUND AND OBJECTIVES

This study aimed to evaluate the utility of high-sensitive troponin T (hs-TnT) for predicting AF recurrence and major adverse cardiovascular events (MACE) after AF ablation.

METHODS AND RESULTS

A total of 227 consecutive patients with AF (mean age, 66 ± 10 years; persistent AF, n = 98) who underwent an initial ablation were enrolled. We measured hs-TnT before AF ablation and divided the patients into three groups according to the hs-TnT level: low, lesser than or equal to 0.005 µg/L (n = 54); medium, 0.006-0.013 µg/L (n = 127); and high, greater than or equal to0.014 µg/L (n = 46). We evaluated the composite endpoint of AF recurrence or MACE (including death, stroke, acute coronary syndrome, and heart failure hospitalization) after the ablation. The median hs-TnT level was 0.008 µg/L. The values of chronic kidney disease prevalence, CHA₂ DS₂ -VASc score, B-type natriuretic peptide level, and left atrial diameter were the highest in the high hs-TnT group among the three groups. During a mean follow-up of 15 ± 8 months, AF recurrence and MACE occurred in 56 (25%) and 9 (4%) patients, respectively. The high hs-TnT group had the highest incidence of AF recurrence and MACE among the three groups (high: 39% and 15%, medium: 22% and 2%, and low: 19% and 0%, respectively; log-rank P < .05). In multivariate analysis, hs-TnT greater than or equal to 0.014 µg/L and persistent AF were independent predictors of the composite endpoint.

CONCLUSION

Hs-TnT may be a useful marker for predicting AF recurrence or MACE after AF ablation.

Prevalence and determinants of exercise-induced left ventricular dysfunction in patients with coronary artery disease

BACKGROUND

The phenomenon of exercise-induced left ventricular dysfunction (LVD) is incompletely understood. Better understanding of its prevalence and determinants might help to address the current potential oversimplification of the relation between physical activity and cardiac health in patients with coronary artery disease (CAD).

METHODS

We prospectively assessed the prevalence and determinants of exercise-induced LVD in patients with stable CAD and normal LV function at rest undergoing bicycle rest/stress myocardial perfusion imaging single-photon emission computed tomography (MPI-SPECT). Exercise-induced LVD was defined as a relevant (5% or more) drop in left ventricular ejection fraction after maximal exercise. High-sensitivity cardiac troponin I/T (Hs-cTnI/T) and N-terminal probrain natriuretic peptide (NT-proBNP) concentrations were measured before exercise to quantify cardiomyocyte injury and hemodynamic cardiac stress, respectively.

RESULTS

Among 317 patients, exercise-induced LVD was present in 83 (26%) patients. Exercise-induced LVD was associated with the extent of exercise-inducible myocardial ischaemia as well as transient ischaemic dilatation. Still, 43% of patients developing exercise-induced LVD did not have functionally relevant CAD. Neither baseline characteristics, nor the quantification of the extent of cardiomyocyte injury and hemodynamic cardiac stress using hs-cTnI/T and NT-proBNP concentrations, respectively, allowed predicting exercise-induced LVD.

CONCLUSION

One out of four patients with stable CAD develops exercise-induced LVD after bicycle exercise test. While the extent of exercise-inducible myocardial ischaemia is a predictor, other still unrecognized mechanisms also seem to play a major role, as nearly half of all patients with exercise-induced LVD do not have functionally relevant CAD.

Biomarker assessment for early infarct size estimation in ST-elevation myocardial infarction

BACKGROUND

High-sensitivity cardiac troponin T (hs-cTnT) represents the biomarker of choice for infarct size (IS) estimation in patients with acute ST-elevation myocardial infarction (STEMI). However, admission values of hs-cTnT are only weakly associated with IS. The aim of this study was to investigate the incremental value of different biomarkers measured on admission for IS estimation in STEMI patients.

METHODS

In this prospective observational study, we included 161 consecutive STEMI patients treated with primary percutaneous coronary intervention (pPCI). The following biomarkers were assessed on admission: hs-cTnT, N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) and neutrophil/lymphocyte ratio (NLR). IS was determined by cardiac magnetic resonance (CMR) imaging 3 (Interquartile range [IQR] 2 to 4) days after the index event.

RESULTS

Patients with large IS (>19% of left ventricular myocardium) showed significantly higher levels of admission hs-cTnT (399.6 vs. 53.4 ng/L, p < .001), NT-pro-BNP (140 vs. 86 ng/L, p = .008) and NLR (6.4 vs. 4.1, p < .001). The combination of hs-cTnT, NT-pro-BNP and NLR on admission resulted in a significantly higher area under the curve (0.78; 95% CI 0.704 to 0.838, (p = .01)) for the prediction of large IS than admission hs-cTnT alone (0.69; 95% CI 0.619 to 0.767).

CONCLUSIONS

In STEMI patients undergoing pPCI, a comprehensive biomarker approach on admission including hs-cTnT, NT-pro-BNP and NLR was significantly better for immediate infarct severity estimation as compared to hs-cTnT alone.

Hypertonic Mannitol for the Prevention of Intradialytic Hypotension: A Randomized Controlled Trial

RATIONALE & OBJECTIVE

Intradialytic hypotension (IDH) is a common complication at the initiation of hemodialysis (HD) therapy, is associated with greater mortality, and may be related to relatively rapid shifts in plasma osmolality. This study sought to evaluate the effect of an intervention to minimize intradialytic changes in plasma osmolality on the occurrence of IDH.

STUDY DESIGN

Double-blind, single-center, randomized, controlled trial.

SETTING & PARTICIPANTS

Individuals requiring initiation of HD for acute or chronic kidney disease.

INTERVENTION

Mannitol, 0.25g/kg/h, versus a similar volume of 0.9% saline solution during the first 3 HD sessions.

OUTCOMES

The primary end point was average decline in systolic blood pressure (SBP). The secondary end point was the proportion of total sessions complicated by IDH (defined as a decrease ≥ 20mm Hg from the pre-HD SBP). Exploratory end points included biomarkers of cardiac and kidney injury.

RESULTS

52 patients were randomly assigned and contributed to 156 study visits. There were no significant differences in average SBP decline between the mannitol and placebo groups (15±11 vs 19±16mm Hg; P = 0.3). The proportion of total sessions complicated by IDH was lower in the mannitol group compared to placebo (25% vs 43%), with a nominally lower risk for developing an episode of IDH (OR, 0.38; 95% CI, 0.14-1.00), though this finding was of borderline statistical significance (P = 0.05). There were no consistent differences in cardiac and kidney injury biomarker levels between treatment groups.

LIMITATIONS

Modest sample size and number of events.

CONCLUSIONS

In this pilot randomized controlled trial studying patients requiring initiation of HD, we found no difference in absolute SBP decline between those who received mannitol and those who received saline solution. However, there were fewer overall IDH events and a nominally lower risk for dialysis sessions being complicated by IDH in the mannitol group. A larger multicenter randomized controlled trial is warranted.

FUNDING

Government funding to an author (Dr Mc Causland is supported by National Institute of Diabetes and Digestive and Kidney Diseases grant K23DK102511).

TRIAL REGISTRATION

Registered at ClinicalTrials.gov with study number NCT01520207.

High-sensitivity troponin T in marathon runners, marathon runners with heart disease and collapsed marathon runners

Endurance exercise is an established cause of cardiac troponin (cTn) elevation, of further interest is whether this rise represents clinical significance. This study compared cTnT rise in three cohorts of marathon runners using a high-sensitivity assay; control runners, those with known heart disease and runners who collapsed at the finish line. Control runners (n = 126) and runners with heart disease (n = 12) were prospectively recruited with cTnT levels measured pre-race and at race completion. Collapsed runners (n = 15) were retrospectively recruited. A mixed model ANCOVA was used to compare the three groups. Pre-race median cTnT for the control group and heart disease groups was 3.9 ng/L (IQR 3.1 ng/L) and 4.1 ng/L (IQR 3.4 ng/L). Post-race values for the three groups were control 45.6 ng/L (IQR 42.5 ng/L), heart disease 41.2 ng/L (IQR 36.1 ng/L), and collapsed 41.9 ng/L (IQR 57.8 ng/L). Post-race cTnT and cTnT change were significantly correlated with pre-race cTnT within the control group (r = 0.38 and 0.30, P < 0.01). There was no difference in post-race cTnT (adjusted for pre-race cTnT) between the three groups. None of the runners reported symptoms suggestive of acute myocardial infarction on follow-up. These results demonstrate that marathon running is associated with an asymptomatic cTnT rise for all runners, and this rise is significantly correlated to baseline cTnT levels, in addition, marathon runners with pre-existing cardiac pathology or who collapse at the finish line do not exhibit an increased cTnT rise compared to healthy runners.

Prognostic role of GDF-15 across the spectrum of clinical risk in patients with NSTE-ACS

Background

Growth differentiation factor (GDF)-15 has been shown to predict cardiovascular (CV) outcomes in acute coronary syndrome (ACS) using non-commercial assays. We evaluated the prognostic performance of GDF-15 measured with the first clinically available assay. Furthermore, we evaluated whether GDF-15 was associated with CV death or heart failure (HF) across the spectrum of risk in non-ST-segment elevation (NSTE)-ACS.

Methods

We measured baseline GDF-15 (Roche, Elecsys) in 4330 patients with NSTE-ACS enrolled in MERLIN-TIMI 36. Patients were categorized using a priori thresholds of GDF-15 levels (<1200, 1200–1800, ≥1800 ng/L) and stratified according to estimated clinical risk per TIMI risk score (0–2, 3–4, and ≥5). Cox modeling included age, sex, BMI, smoking, HF, diabetes, renal function, NT-proBNP, hsTnT, and hsCRP.

Results

There were 2286 (53%), 1104 (25%), and 940 (22%) pts with GDF-15 <1200, 1200–1800, and ≥1800 respectively. GDF-15 was significantly associated after multivariable adjustment with CV death/HF modeled either as a categorical (1200–1800 ng/L: Adj hazard ratios [HR] 1.55 [1.09–2.19]; ≥1800 ng/L: Adj HR 1.94 [1.34–2.79]) or continuous variable (Adj HR 1.36 [1.16–1.60] per 1-unit increase in log2-transformed GDF-15). Notably, there was an interaction (Pinteraction=0.003) between TIMI risk score and GDF-15, with GDF-15 identifying the greatest incremental relative risk in those at lowest risk based on the TIMI risk score alone.

Conclusions

Using a clinically available assay, GDF-15 can be applied using established cut-off points to independently predict risk of CV death/HF in patients with NSTE-ACS. This incremental risk appears to be particularly robust among individuals traditionally identified as low risk.

The appropriateness of coronary investigation in myocardial injury and type 2 myocardial infarction (ACT-2): A randomized trial design

BACKGROUND

Elevated troponin level findings among patients presenting with suspected acute coronary syndrome (ACS) or another intercurrent illness undeniably identifies patients at increased risk of mortality. Whilst enhancing our capacity to discriminate risk, the use of high-sensitivity troponin assays frequently identifies patients with myocardial injury (i.e. troponin rise without acute signs of myocardial ischemia) or type 2 myocardial infarction (T2MI; oxygen supply-demand imbalance). This leads to the clinically challenging task of distinguishing type 1 myocardial infarction (T1MI; coronary plaque rupture) from myocardial injury and T2MI in the context of concurrent acute illness. Diagnostic discernment in this context is crucial because MI classification has implications for further investigation and care. Early invasive management is of well-established benefit among patients with T1MI. However, the appropriateness of this investigation in the heterogeneous context of T2MI, where there is high competing mortality risk, remains unknown. Although coronary angiography in T2MI is advocated by some, there is insufficient evidence in existing literature to support this opinion as highlighted by current national guidelines.

OBJECTIVE

The objective is to evaluate the clinical and economic impact of early invasive management with coronary angiography in T2MI in terms of all-cause mortality and cost effectiveness.

DESIGN

This prospective, pragmatic, multicenter, randomized trial among patients with suspected supply demand ischemia leading to troponin elevation (n=1,800; T2MI [1,500], chronic myocardial injury [300]) compares the impact of invasive angiography (or computed tomography angiography as per local preference) within 5 days of randomization versus conservative management (with or without functional testing at clinician discretion) on all-cause mortality by 2 years. Randomized treatment allocation will be stratified by baseline estimated risk of mortality using the Acute Physiology, Age, and Chronic Health Evaluation (APACHE) III risk score. Cost-effectiveness will be evaluated by follow-up on clinical events, quality of life, and resource utilization over 24 months.

SUMMARY

Ascertaining the most appropriate first-line investigative strategy for these commonly encountered high-risk T2MI patients in a randomized comparative study will be pivotal in informing evidence-based guidelines that lead to better patient and health care outcomes.

Serum neprilysin and the risk of death in patients with out-of-hospital cardiac arrest of non-traumatic origin

BACKGROUND

Early risk stratification remains an unmet clinical need in patients with in out-of-hospital cardiac arrest. We hypothesised that soluble neprilysin may represent a promising biomarker in patients with out-of-hospital cardiac arrest of non-traumatic origin and provide new pathobiological insight.

METHODS

This pilot study was a biomarker analysis from the Heidelberg Resuscitation Registry. Serum soluble neprilysin levels on admission were measured in 144 patients with successful return of spontaneous circulation after out-of-hospital cardiac arrest of non-traumatic origin. The primary endpoint was time to all-cause mortality. KM Event Rates are reported. Cox models were adjusted for age, bystander resuscitation, initial ECG rhythm, baseline estimated glomerular filtration rate, baseline lactate, left ventricular function at baseline, and targeted temperature management.

RESULTS

In total, 90 (62.5%) patients died over a follow-up of at least 30 days. Soluble neprilysin correlated weakly with high-sensitivity troponin T (r=0.18, P=0.032) but did not correlate significantly with estimated glomerular filtration rate (r=-0.12) or lactate (r=0.11). Patients with elevated soluble neprilysin levels on admission were at significantly higher risk of all-cause mortality (Q4 69.1% vs. Q1 48.4%). After multivariable adjustment, soluble neprilysin in the top quartile (Q4) was significantly associated with all-cause mortality (Q4 vs. Q1: adjusted hazard ratio 2.48 (1.20-5.12)). In an adjusted multimarker model including high-sensitivity troponin T and high-sensitivity C-reactive protein, soluble neprilysin and high-sensitivity troponin T remained independently associated with all-cause mortality (soluble neprilysin: adjusted hazard ratio 2.27 (1.08-4.78); high-sensitivity troponin T: adjusted hazard ratio 3.40 (1.63-7.09)).

CONCLUSION

Soluble neprilysin, measured as early as on hospital admission, was independently associated with all-cause mortality in patients with out-of-hospital cardiac arrest of non-traumatic origin and may prove to be useful in the estimation of risk in these patients.

Direct Comparison of Cardiac Troponin T and I Using a Uniform and a Sex-Specific Approach in the Detection of Functionally Relevant Coronary Artery Disease

BACKGROUND

We aimed to directly compare high-sensitivity cardiac troponin I (hs-cTnI) and high-sensitivity cardiac troponin T (hs-cTnT) in the detection of functionally relevant coronary artery disease (fCAD).

METHODS

Consecutive patients referred with clinical suspicion of fCAD and no structural heart disease other than coronary artery disease were included. The presence of fCAD was based on rest/stress myocardial perfusion single-photon emission computed tomography/computed tomography and coronary angiography. hs-cTnI and hs-cTnT concentrations were measured in a blinded fashion. Diagnostic accuracy was quantified using the area under the ROC curve (AUC) and evaluated both for uniform use in all patients and for sex-specific use in women and men separately. The prognostic end point was major adverse cardiac events (MACEs; cardiovascular death or myocardial infarction) within 2 years. For the prognostic performance, we used a multivariable model comparison with the Akaike information criterion (AIC).

RESULTS

fCAD was detected in 613 of 2062 patients (29.7%) overall, 112 of 664 of women (16.9%), and 501 of 1398 of men (35.8%). hs-cTnI and hs-cTnT had comparable diagnostic accuracy when assessed for uniform use in all patients (AUC, 0.68 vs 0.66; P = 0.107) and separately in women (AUC, 0.68 vs 0.63; P = 0.068) and men (AUC, 0.65 vs 0.64; P = 0.475). However, women required lower rule-out cutoffs to achieve high sensitivity, and men needed higher rule-in cutoffs to achieve high specificity. hs-cTnI and hs-cTnT were strongly and independently associated with MACE within 2 years (P &lt; 0.001), with comparable prognostic accuracies by the AIC.

CONCLUSIONS

hs-cTnI and hs-cTnT provide moderate and comparable diagnostic accuracy. Sex-specific cutoffs may be preferred. The prognostic utility of both troponins is comparable.

The feasibility of the 1-h high-sensitivity cardiac troponin T algorithm to rule-in and rule-out acute myocardial infarction in Thai emergency patients: an observational study

Background

The 3-h high-sensitivity cardiac troponin T (hs-cTnT) algorithm is the most commonly used scheme to diagnose acute myocardial infarction. The 1-h hs-cTnT algorithm has recently been approved by the European Society of Cardiology as an alternative algorithm for earlier diagnosis. If the hs-cTnT test cannot discriminate the diagnosis of the patient at 1 h, the patient is defined as observational group. Their test must be repeated at 3 h. A high prevalence of this group may indicate a low clinical utility of the 1-h hs-cTnT algorithm. This study was aimed to estimate the proportion of the observational group in Thai emergency department (ED) patients and also the time to rule-in/out between both the algorithms.

Methods

A historical control study was conducted in patients with chest pain for 1–12 h at the ED of Siriraj Hospital, Bangkok, Thailand. The study compared two groups: one prospective group of all patients evaluated with the 1-h hs-cTnT algorithm between June and September 2017 and one historical control group evaluated with the 3-h hs-cTnT algorithm between January and March 2017.

Results

A total of 130 patients were included (3-h hs-cTnT algorithm group n = 65 and 1-h hs-cTnT algorithm group n = 65). Twelve patients [18.5% (95% CI 10.0–30.1)] were categorized as observational group in the 1-h hs-cTnT algorithm group. The mean rule-in/out times in the 3-h hs-cTnT algorithm and 1-h hs-cTnT algorithm groups were 238 min (SD 63.3) and 134 min (SD 68.5), respectively (both p < 0.001). The time to disposition was also shortened in the 1-h hs-cTnT algorithm group (p <  0.001). Multivariable regression analysis performed to identify and adjust for confounders among patient characteristics revealed no significant confounders.

Conclusions

The use of the 1-h hs-cTnT algorithm in the ED resulted in an acceptable proportion in the observational group and a decreased time to rule-in/out compared with the 3-h hs-cTnT algorithm.