Cardiac biomarker responses following high-intensity interval and continuous exercise: the influence of ACE-I/D gene polymorphism and training status in men.

This study aimed to investigate the relationship between pre- and postexercise cardiac biomarker release according to athletic status (trained vs. untrained) and to establish whether the I/D polymorphism in the angiotensin-converting enzyme (ACE) gene had an influence on cardiac biomarkers release with specific regard on the influence of the training state. We determined cardiac troponin I (cTnI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in 29 trained and 27 untrained male soccer players before and after moderate-intensity continuous exercise (MICE) and high-intensity interval exercise (HIIE) running tests. Trained soccer players had higher pre (trained: 0.014 ± 0.007 ng/mL; untrained: 0.010 ± 0.005 ng/mL) and post HIIE (trained: 0.031 ± 0.008 ng/mL; untrained: 0.0179 ± 0.007) and MICE (trained: 0.030 ± 0.007 ng/mL; untrained: 0.018 ± 0.007) cTnI values than untrained subjects, but the change with exercise (ΔcTnI) was similar between groups. There was no significant difference in baseline and postexercise NT-proBNP between groups. NT-proBNP levels were elevated after both HIIE and MICE. Considering three ACE genotypes, the mean pre exercise cTnI values of the trained group (DD: 0.015 ± 0.008 ng/mL, ID: 0.015 ± 0.007 ng/mL, and II: 0.014 ± 0.008 ng/mL) and their untrained counterparts (DD: 0.010 ± 0.004 ng/mL, ID: 0.011 ± 0.004 ng/mL, and II: 0.010 ± 0.006 ng/mL) did not show any significant difference. To sum up, noticeable difference in baseline cTnI was observed, which was related to athletic status but not ACE genotypes. Neither athletic status nor ACE genotypes seemed to affect the changes in cardiac biomarkers in response to HIIE and MICE, indicating that the ACE gene does not play a significant role in the release of exercise-induced cardiac biomarkers indicative of cardiac damage in Iranian soccer players.NEW & NOTEWORTHY Our study investigated the impact of athletic status and angiotensin-converting enzyme (ACE) gene I/D polymorphism on cardiac biomarkers in soccer players. Trained players showed higher baseline cardiac troponin I (cTnI) levels, whereas postexercise ΔcTnI remained consistent across groups. N-terminal pro-brain natriuretic peptide increased after exercise in both groups, staying within normal limits. ACE genotypes did not significantly affect pre-exercise cTnI. Overall, athletic status influences baseline cTnI, but neither it nor ACE genotypes significantly impact exercise-induced cardiac biomarker responses in this population.

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.

Prospective Multicenter Screening With High-Sensitivity Cardiac Troponin T for Wild-Type Transthyretin Cardiac Amyloidosis in Outpatient and Community-Based Settings.

BACKGROUND: High-sensitivity cardiac troponin T (hs-cTnT) was proposed as a simple and useful diagnostic tool for cardiac amyloidosis (CA). We performed exploratory systemic screening using hs-cTnT to detect wild-type transthyretin CA (ATTRwt-CA) in outpatient and community-based settings. METHODS AND RESULTS: This study was a prospective multicenter study including 8 internal medicine clinics in Kochi Prefecture, Japan. Consecutive individuals aged ≥70 years who visited those clinics as outpatients were enrolled. Patients with a prior diagnosis of CA or a history of heart failure hospitalization were excluded. We measured hs-cTnT levels in the enrolled individuals at each clinic, and those with elevated hs-cTnT levels (≥0.03ng/mL) received further detailed examination, including remeasurement of hs-cTnT. The diagnosis of ATTRwt-CA was confirmed by biopsy-proven transthyretin. Of 1,141 individuals enrolled in the study, 55 (4.8%) had elevated hs-cTnT levels. Of the 33 patients who underwent further examination, 22 had elevated hs-cTnT levels at remeasurement. Finally, 2 men were diagnosed with ATTRwt-CA. The prevalence of ATTRwt-CA was 9.1% (2/22) among patients with elevated hs-cTnT levels at two examinations, and at least 0.18% (2/1,141) in the whole study population. CONCLUSIONS: Measurement of hs-cTnT will help to screen for patients with undiagnosed ATTRwt-CA in primary care practice.

Analytical verification of the Atellica VTLi point of care high sensitivity troponin I assay.

OBJECTIVES: The Siemens Point-of-Care Testing (POC) Atellica® VTLi high-sensitivity troponin I (hsTnI) device has been previously validated. Verification independently provides evidence that an analytical procedure fulfils concordance with laboratory assays, imprecision, and hemolysis interference requirements. METHODS: Five whole blood samples spanning the measuring interval were analysed 20 times in succession. Hemolysis interference was assessed at three troponin concentrations by spiking five hemolysate concentrations to plasma to achieve free hemoglobin concentrations 35-1,000 mg/dL. Concordance between whole blood (VTLi) and plasma on laboratory analysers (Beckman, Roche, Siemens) was assessed by Pearson correlation and kappa statistics at the (LOQ) and upper reference limit (URL). This was repeated for frozen plasma samples. RESULTS: Coefficients of variation for whole blood were <10 % for whole blood troponin concentrations of 9.2 and 15.9 ng/L, thus below the URL. Hemolysis positively interfered; at 250 mg/dL affecting the low troponin sample (+3 ng/L; +60 %) and high troponin sample (+37 ng/L; +24 %). Correlation coefficients were 0.98, 0.90 and 0.97 between VTLi and Beckman, Roche and Siemens assays respectively. Corresponding kappa statistics were 0.80, 0.73 and 0.84 at the LOQ and 0.70, 0.44 and 0.67 at the URL. CONCLUSIONS: Concordances between VTLi and laboratory assays were at least non-inferior to those between laboratory assays. Imprecision met manufacturer claims and was consistent with a high sensitivity assay. There is potential for hemolysis interference, highlighting the need for quality samples. The results support performance characteristics previously reported in validation studies, and the device offers acceptable performance for use within intended medical settings.

To rule-in, or not to falsely rule-out, that is the question: evaluation of hs-cTnT EQA performance in light of the ESC-2020 guideline.

OBJECTIVES: To accurately evaluate non-ST-elevated acute cardiac syndrome (NSTE-ACS), the quality of high-sensitive cardiac troponin (hs-cTn) assays is of vital importance. The 2020 revision of the NSTE-ACS guideline includes clinical decision-limits (CDL's) to both rule-in and rule-out NSTE-ACS for most commercially available platforms, providing both 0/1 h and 0/2 h delta limits. Our study evaluated whether laboratories are able to meet the analytical performance specifications for imprecision (APS) for hs-cTnT. METHODS: Results from external quality assurance (EQA) in commutable samples were used to evaluate the current and historic performance of analyzers. The performance of analyzers that either passed or failed to comply with 0/1 h-APS were used on a real-world dataset of first hs-cTnT-values to simulate 10.000 samples of t=0, t=1 and t=2 h values with multiple delta's for all relevant CDL's. We compared the simulated values to the input values to obtain the percentage of aberrant results simulated. RESULTS: The majority of analyzers complies with APS for rule-in in 2022 (0/1 h: 90.4 % and 0/2 h: 100 %), compliance for the 0/1 h rule-out is still far from optimal (0/1 h: 30.7 %, 0/2 h: 75.4 %), with improving compliance over the past years (rule-in p=<0.0001, rule-out p=0.011, χ2). Whilst 0/1 h-APS-passing analyzers have a minute risk to falsely rule-out patients whom should be ruled-in (0.0001 %), failing performance increases this risk to 2.1 % upon using 0/1 h CDL's. Here, adopting 0/2 h CDL's is favorable (0.01 %). CONCLUSIONS: Laboratories that fail to meet hs-cTnT 0/1 h-APS should improve their performance to the required and achievable level. Until performance is reached clinics should adopt the 0/2 h CDL's.

Analytical validation of the Mindray CL1200i analyzer high sensitivity cardiac troponin I assay: MERITnI study.

OBJECTIVES: This study performed an analytical validation study of the Mindray high-sensitivity cardiac troponin I (hs-cTnI) assay addressing limit of blank (LoB), limit of detection (LoD), precision, linearity, analytical specificity and sex-specific 99th percentile upper reference limits. METHODS: LoB, LoD, precision, linearity and analytical specificity were studied according to Clinical and Laboratory Standards Institute. We used one reagent lot and one CL1200i analyzer. Skeletal troponin I and T, cardiac troponin T, troponin C, actin, tropomyosin, myosin light chain, myoglobin and creatine kinase (CK-MB) were studied for cross-reactivity. Interference with biotin was examined. Lithium heparin samples (one freeze thaw cycle) from healthy males and females were measured to determine the 99th percentiles by using the non-parametric method. Analyses were performed before and after excluding subjects with clinical conditions and/or increased surrogate biomarkers. RESULTS: The Mindray hs-cTnI assay met criteria to be considered as a hs-cTn assay. LoB and LoD was <0.1 ng/L and 0.1 ng/L, respectively. Repeatability had a coefficient of variation 1.2-3.8 %, and within-laboratory imprecision 1.7-5.0 %. The measuring interval ranged from 1.1 to 28,180 ng/L. The analytical specificity was clinically acceptable for the interferents studied. After exclusions, the 99th percentile URLs obtained were 10 ng/L overall, 5 ng/L for females and 12 ng/L for males. CONCLUSIONS: Analytical observations of the Mindray hs-cTnI assay demonstrated excellent LoB, LoD, precision, linearity and analytical specificity, that were in alignment with the manufacturer's claims and regulatory guidelines for hs-cTnI. The assay is suitable for clinical investigation for patient-oriented studies.

Diagnostic performance of a point of care high-sensitivity cardiac troponin I assay and single measurement evaluation to rule out and rule in acute coronary syndrome.

OBJECTIVES: About 10 million individuals in USA presented annually in the emergency department (ED) with chest pain or with signs and symptoms of acute coronary syndrome (ACS). The advent of point of care (POC) devices, able to measure high sensitivity troponin, are a very interesting tool in the ED setting for its rapid turnaround time (<10 min). METHODS: The present study evaluates the diagnostic performance of the Atellica VTLi (Siemens) in real life setting using the clinical data derived from integrated diagnoses of emergency room staff and cardiologist and in comparison with standard laboratory hs-cTnT assay (Cobas 8000, Elecsys, Roche). 966 patients admitted to the emergency department of "G. Mazzini Hospital" in Teramo, Italy, from July 27, 2022, through June 09, 2023, were enrolled. RESULTS: The diagnostic performance of POC hs-cTnI was evaluated. An appropriate POC hs-cTnI threshold values <4 ng/L supplied a sensitivity and an NPV of 100 % (95 % CI: 99.5-100) in order to achieve rapid rule out for MI through a single measurement at patient presentation in the ED. Furthermore, a derivation POC hs-cTnI concentration >54 ng/L provided a specificity of 97.2 % (95 % CI: 95.9-98.1) and a PPV of 43.5 % (95 % CI: 40.3-46.7) for ruling in MI. CONCLUSIONS: This platform showed comparable diagnostic performance for myocardial infarction to the central laboratory. Our data suggest the possible use of the Atellica VTLi hs-cTnI POC assay either in emergency department of urban medical centre, either in rural hospital for triage and patient management.

Effect of dexmedetomidine on postoperative high-sensitivity cardiac troponin T in patients undergoing video-assisted thoracoscopic surgery: a prospective, randomised controlled trial.

BACKGROUND: One-lung ventilation and intrathoracic operations during thoracoscopic surgery often result in intraoperative hypoxaemia and haemodynamic fluctuations, resulting in perioperative myocardial injury. Dexmedetomidine, an alpha-2 (α-2) agonist, has demonstrated myocardial protection. We hypothesize that the routine intravenous administration of dexmedetomidine could reduce the extent of myocardial injury during video-assisted thoracoscopic surgery (VATS). METHODS: The study included patients aged ≥ 45 years, classified as American Society of Anesthesiologists physical status I-III, who underwent general anesthesia for video-assisted thoracoscopic surgery. The patients were randomly assigned to either the intervention group, receiving general anesthesia with dexmedetomidine, or the control group, receiving general anesthesia without dexmedetomidine. Patients in the intervention group received a loading dose of dexmedetomidine (0.5 µg·kg-1) before anesthesia induction, followed by a continuous infusion (0.5 µg·kg-1·h-1) until the completion of the surgery. Placebos (saline) were administered for the control group to match the treatment. The primary outcome assessed was the high-sensitivity cardiac troponin T on postoperative day 1. Additionally, the incidence of myocardial injury after noncardiac surgery (MINS) was noted. RESULTS: A total of 110 participants completed this study. The median [interquartile range (IQR)] concentration of hs-cTnT on postoperative day 1 was lower in the intervention group compared with the control group (7 [6-9] vs. 8 [7-11] pg·ml-1; difference in medians,1 pg·ml-1; 95% confidence interval [CI], 0 to 2; P = 0.005). Similarly, on postoperative day 3, the median [IQR] concentration of hs-cTnT in the intervention group was also lower than that in the control group (6 [5-7] vs. 7 [6-9]; difference in medians,1 pg·ml-1; 95%CI, 0 to 2; P = 0.011). Although the incidence of MINS was not statistically significant (the intervention group vs. the control group, 3.8% vs. 9.1%, P = 0.465), there was a decreasing trend in the incidence of MINS in the intervention group. CONCLUSION: The administration of perioperative dexmedetomidine in patients ≥ 45 years undergoing video-assisted thoracoscopic surgery could lower the release of postoperative hs-cTnT without reducing incidence of myocardial injury. TRIAL REGISTRATION: chictr.org.cn (ChiCTR2200063193); prospectively registered 1 September 2022.

High-sensitivity troponins and mortality in the general population.

AIMS: Cardiac troponin T and I can be measured using a number of high-sensitivity (hs) assays. This study aimed to characterize correlations between four such assays and test their comparative associations with mortality. METHODS AND RESULTS: Among adults without cardiovascular disease in the 1999-2004 National Health and Nutrition Examination Survey, hs-troponin T was measured using one assay (Roche) and hs-troponin I using three assays (Abbott, Siemens, and Ortho). Cox regression was used to estimate associations with all-cause and cardiovascular mortality. Pearson's correlation coefficients comparing concentrations from each assay ranged from 0.53 to 0.77. There were 2188 deaths (488 cardiovascular) among 9810 participants. Each hs-troponin assay [log-transformed, per 1 standard deviation (SD)] was independently associated with all-cause mortality: hazard ratio (HR) 1.20 [95% confidence interval (CI) 1.13-1.28] for Abbott hs-troponin I; HR 1.10 (95% CI 1.02-1.18) for Siemens hs-troponin I; HR 1.23 (95% CI 1.14-1.33) for Ortho hs-troponin I; and HR 1.31 (95% CI 1.21-1.42) for Roche hs-troponin T. Each hs-troponin assay was also independently associated with cardiovascular mortality (HR 1.44 to 1.65 per 1 SD). Associations of hs-troponin T and all-cause and cardiovascular mortality remained significant after adjusting for hs-troponin I. Furthermore, associations of hs-troponin I remained significant after mutually adjusting for hs-troponin I from the other individual assays: e.g. cardiovascular mortality HR 1.46 (95% CI 1.19-1.79) for Abbott after adjustment for the Siemens assay and HR 1.29 (95% CI 1.09-1.53) for Abbott after adjustment for the Ortho assay. CONCLUSION: This study demonstrates only modest correlations between hs-troponin T and three hs-troponin I assays and that hs-troponin I assays can provide distinct risk information for mortality in the general population.

Accelerated -Rule-Out of acute Myocardial Infarction using prehospital copeptin and in-hospital troponin: The AROMI study.

AIMS: The present acute myocardial infarction (AMI) rule-out strategies are challenged by the late temporal release of cardiac troponin. Copeptin is a non-specific biomarker of endogenous stress and rises early in AMI, covering the early period where troponin is still normal. An accelerated dual-marker rule-out strategy combining prehospital copeptin and in-hospital high-sensitivity troponin T could reduce length of hospital stay and thus the burden on the health care systems worldwide. The AROMI trial aimed to evaluate if the accelerated dual-marker rule-out strategy could safely reduce length of stay in patients discharged after early rule-out of AMI. METHODS AND RESULTS: Patients with suspected AMI transported to hospital by ambulance were randomized 1:1 to either accelerated rule-out using copeptin measured in a prehospital blood sample and high-sensitivity troponin T measured at arrival to hospital or to standard rule-out using a 0 h/3 h rule-out strategy. The AROMI study included 4351 patients with suspected AMI. The accelerated dual-marker rule-out strategy reduced mean length of stay by 0.9 h (95% confidence interval 0.7-1.1 h) in patients discharged after rule-out of AMI and was non-inferior regarding 30-day major adverse cardiac events when compared to standard rule-out (absolute risk difference -0.4%, 95% confidence interval -2.5 to 1.7; P-value for non-inferiority = 0.013). CONCLUSION: Accelerated dual marker rule-out of AMI, using a combination of prehospital copeptin and first in-hospital high-sensitivity troponin T, reduces length of hospital stay without increasing the rate of 30-day major adverse cardiac events as compared to using a 0 h/3 h rule-out strategy.

High-sensitivity cardiac troponin T in infants exposed to anti-Ro antibodies.

OBJECTIVES: Cardiac involvement in neonatal lupus erythematosis (NLE) can present as myocarditis/endocardial fibroelastosis (EFE). It is unknown whether high-sensitivity cardiac troponin T (hs-cTnT) is useful in identifying subclinical myocardial inflammation in infants exposed prenatally to anti-Ro antibodies. This study reports hs-cTnT levels in infants exposed to anti-Ro antibodies with/without cardiac NLE and reports cardiac MRI (CMR) findings in a subset of these children. METHODS: The study included 45 consecutive infants exposed prenatally to anti-Ro antibodies with (n = 7) or without (n = 38) cardiac NLE, who were seen at the SickKids NLE Clinic between 2012 and 2014. Hs-cTnT levels were measured at least once, and those infants with values of ≥30 ng/l were offered the opportunity to undergo CMR. Descriptive statistics were performed. RESULTS: Of 38 infants without cardiac NLE, 25 had a hs-cTnT level of ≥30 ng/l (including 1 of >113 ng/l); of these, 8 underwent CMR (all without myocarditis/EFE). All 7 infants with cardiac NLE had at least one hs-cTnT level of ≥30 ng/l, but only 2/7 had a level of >113 ng/l; 4/7 infants with cardiac NLE had CMR (all without myocarditis/EFE); 6/7 infants with cardiac NLE had their steroid treatment adjusted based on the trend in their hs-cTnT levels. CONCLUSION: Only 3/45 anti-Ro antibodies-exposed infants had hs-cTnT values outside the reference range reported in healthy infants. None of 12 infants who had CMR had subclinical myocarditis/EFE. Routine measurement of hs-cTnT in every anti-Ro antibody-exposed infant is not indicated. Further studies are needed to define the role of hs-cTnT as a biomarker for cardiac NLE.

Longitudinal Changes in Cardiac Troponin and Risk of Heart Failure Among Black Adults.

BACKGROUND: Among Black adults, high-sensitivity cardiac troponin I (hs-cTnI) is associated with heart failure (HF) risk. The association of longitudinal changes in hs-cTnI with risk of incident HF, HF with reduced and preserved ejection fraction (HFrEF and HFpEF, respectively), among Black adults is not well-established. METHODS AND RESULTS: This study included Black participants from the Jackson Heart Study with available hs-cTnI data at visits 1 (2000-2004) and 2 (2005-2008) and no history of cardiovascular disease. Cox models were used to evaluate associations of categories of longitudinal change in hs-cTnI with incident HF risk. Among 2423 participants, 11.6% had incident elevation in hs-cTnI at visit 2, and 16.9% had stable or improved elevation (≤50% increase in hs-cTnI), and 4.0% had worsened hs-cTnI elevation (>50% increase). Over a median follow-up of 12.0 years, there were 139 incident HF hospitalizations (64 HFrEF, 58 HFpEF). Compared with participants without an elevated hs-cTnI, those with incident, stable or improved, or worsened hs-cTnI elevation had higher HF risk (adjusted hazard ratio 3.20 [95% confidence interval, 1.92-5.33]; adjusted hazard ratio 2.40, [95% confidence interval, 1.47-3.92]; and adjusted hazard ratio 8.10, [95% confidence interval, 4.74-13.83], respectively). Similar patterns of association were observed for risk of HFrEF and HFpEF. CONCLUSIONS: Among Black adults, an increase in hs-cTnI levels on follow-up was associated with a higher HF risk. LAY SUMMARY: The present study included 2423 Black adults from the Jackson Heart Study with available biomarkers of cardiac injury and no history of cardiovascular disease at visits 1 and 2. The majority of participants did not have evidence of cardiac injury at both visits (67.5%), 11.6% had evidence of cardiac injury only on follow-up, 14.5% had stable elevations, 4.0% had worsened elevations, and 2.4% had improved elevations of cardiac injury biomarkers during follow-up. Compared with participants without evidence of cardiac injury, those with new, stable, and worsened levels of cardiac injury had a higher risk of developing heart failure. TWEET: Among Black adults, persistent or worsening subclinical myocardial injury is associated with an elevated risk of HF.

Improved Utilization of Serial Testing Without Increased Admissions after Implementation of High-Sensitivity Troponin I: a Controlled Retrospective Cohort Study.

BACKGROUND: Guidelines recommend high-sensitivity cardiac troponin (hs-cTn) for diagnosis of myocardial infarction. Use of hs-cTn is increasing across the U.S., but questions remain regarding clinical and operational impact. Prior studies have had methodologic limitations and yielded conflicting results. OBJECTIVE: To evaluate the impact of transitioning from conventional cardiac troponin (cTn) to hs-cTn on test and resource utilization, operational efficiency, and patient safety. DESIGN: Retrospective cohort study in two New York City hospitals during the months before and after transition from conventional cTn to hs-cTn at Hospital 1. Hospital 2 served as a control. PARTICIPANTS: Consecutive emergency department (ED) patients with at least one cTn test resulted. INTERVENTION: Multifaceted hs-cTn intervention bundle, including a 0/2-h diagnostic algorithm for non-ST-elevation myocardial infarction, an educational bundle, enhancements to the electronic medical record, and nursing interventions to facilitate timed sample collection. MAIN MEASURES: Primary outcomes included serial cTn test utilization, probability of hospital admission, ED length of stay (LOS), and among discharged patients, probability of ED revisit within 72 h resulting in hospital admission. Multivariable regression models adjusted for age, sex, temporal trends, and interhospital differences. KEY RESULTS: The intervention was associated with increased use of serial cTn testing (adjusted risk difference: 48 percentage points, 95% CI: 45-50, P < 0.001) and ED LOS (adjusted geometric mean difference: 50 min, 95% CI: 50-51, P < 0.001). There was no significant association between the intervention and probability of admission (adjusted relative risk [aRR]: 0.99, 95% CI: 0.89-1.1, P = 0.81) or probability of ED revisit within 72 h resulting in admission (aRR: 1.1, 95% CI: 0.44-2.9, P = 0.81). CONCLUSIONS: Implementation of a hs-cTn intervention bundle was associated with an improvement in serial cTn testing, a neutral effect on probability of hospital admission, and a modest increase in ED LOS.

Using logistic regression models to investigate the effects of high-sensitivity cardiac troponin T confounders on ruling in acute myocardial infarction.

OBJECTIVES: Confounding factors, including sex, age, and renal dysfunction, affect high-sensitivity cardiac troponin T (hs-cTnT) concentrations and the acute myocardial infarction (AMI) diagnosis. This study assessed the effects of these confounders through logistic regression models and evaluated the diagnostic performance of an optimized, integrated prediction model. METHODS: This retrospective study included a primary derivation cohort of 18,022 emergency department (ED) patients at a US medical center and a validation cohort of 890 ED patients at a Canadian medical center. Hs-cTnT was measured with 0/3 h sampling. The primary outcome was index AMI diagnosis. Logistic regression models were optimized to predict AMI using delta hs-cTnT and its confounders as covariates. The diagnostic performance of model cutoffs was compared to that of the hs-cTnT delta thresholds. Serial logistic regressions were carried out to evaluate the relationship between covariates. RESULTS: The area under the curve of the best-fitted model was 0.95. The model achieved a 90.0% diagnostic accuracy in the validation cohort. The optimal model cutoff yielded comparable performance (90.5% accuracy) to the optimal sex-specific delta thresholds (90.3% accuracy), with 95.8% agreement between the two diagnostic methods. Serial logistic regressions revealed that delta hs-cTnT played a more predominant role in AMI prediction than its confounders, among which sex is more predictive of AMI (total effect coefficient 1.04) than age (total effect coefficient 0.05) and eGFR (total effect coefficient -0.008). CONCLUSIONS: The integrated prediction model incorporating confounding factors does not outperform hs-cTnT delta thresholds. Sex-specific hs-cTnT delta thresholds remain to provide the highest diagnostic accuracy.

The association of cardiac troponin and cardiovascular events in patients with concomitant heart failure preserved ejection fraction and atrial fibrillation.

BACKGROUND: Limited data are available for risk stratification in patients with atrial fibrillation (AF) and combined heart failure with preserved ejection fraction (HFpEF). We aimed to explore the prognostic utility of high-sensitivity cardiac troponin I (hs-cTnI) in patients with newly detected AF and concomitant HFpEF. METHODS: From August 2014 to December 2016, 2,361 patients with newly detected AF were polled in a retrospective single-center registry. Of which, 634 patients were eligible for HFpEF diagnosis (HFA-PEFF score ≥ 5) and 165 patients were excluded with exclusion criteria. Finally, 469 patients are classified into elevated or non-elevated hs-cTnI groups based on the 99th percentile upper reference limit (URL). The primary outcome was the incidence of major adverse cardiac and cerebrovascular events (MACCE) during follow-up. RESULTS: In 469 patients, 295 were stratified into the non-elevated hs-cTnI group (< 99th percentile URL of hs-cTnI) and 174 were placed in the elevated hs-cTnI group (≥ 99th percentile URL of hs-cTnI). The median follow-up period was 24.2 (interquartile range, 7.5-38.6) months. During the follow-up period, 106 patients (22.6%) in the study population experienced MACCE. In a multivariable Cox regression model, the elevated hs-cTnI group had a higher incidence of MACCE (adjusted hazard ratio [HR], 1.54; 95% confidence interval [CI], 1.08-2.55; p = 0.03) and coronary revascularization-caused readmission (adjusted HR, 3.86; 95% CI, 1.39-15.09; p = 0.02) compared with the non-elevated hs-cTnI group. The incidence of heart failure-caused readmission tended to occur more frequently in the elevated hs-cTnI group (8.5% versus 15.5%; adjusted HR, 1.52; 95% CI, 0.86-2.67; p = 0.08). CONCLUSIONS: One-fifth of patients with AF and concomitant HFpEF experienced MACCE during follow-up, and elevated hs-cTnI was independently associated with higher risk of MACCE, as driven by heart failure and revascularization-caused readmission. This finding suggested that hs-cTnI may be a useful tool in individualized risk stratification of future cardiovascular events in patients with AF and concomitant HFpEF.

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

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

Clinical performance of 0/1 h cardiac troponin algorithm for diagnosing non-STEMI in an emergency setting.

BACKGROUND: Non-ST-segment elevation myocardial infarction (NSTEMI) is a common form of acute myocardial infarction and rapid and accurate diagnosis is crucial for timely treatment. Current guidelines recommend using high-sensitivity cardiac troponin (hs-cTn) assays to determine circulating cTnI or cTnT levels. While the accuracy of the 0 h/1 h algorithm for diagnosing NSTEMI in different regions and patient populations remains controversial. Additionally, point-of-care testing (POCT) cTn assays have the potential to provide troponin readings to physicians within 15 min, but their accuracy in diagnosing NSTEMI in the emergency department (ED) requires further investigation. METHODS: A single-center prospective observational cohort study was conducted at Shaanxi Provincial People's Hospital to assess the analytical and diagnostic performance of the laboratory-based Roche Modular E170 hs-cTnT using the 0 h/1 h algorithm with Radiometer AQT90-flex POCT cTnT assay in undifferentiated chest pain patients presenting to the ED. Whole-blood samples were collected and hs-cTnT and POCT cTnI were measured simultaneously at baseline and after 1 h. RESULTS: The study results showed that the POCT cTnT assay using the 0 h/1 h algorithm had comparable diagnostic accuracy to the laboratory-based Roche Modular E170 hs-cTnT assay in diagnosing NSTEMI in patients with chest pain. CONCLUSION: The laboratory-based Roche Modular E170 hs-cTnT using the 0 h/1 h algorithm is reliable and accurate method for diagnosing NSTEMI in undifferentiated chest pain patients presenting to the ED. POCT cTnT assay has comparable diagnostic accuracy to the hs-cTnT assay and its rapid turnaround time makes it a valuable tool in expediting the diagnostic workup of chest pain patients.

High-sensitivity cardiac troponin I after coronary artery bypass grafting for post-operative decision-making.

AIMS: Current troponin cut-offs suggested for the post-operative workup of patients following coronary artery bypass graft (CABG) surgery are based on studies using non-high-sensitive troponin assays or are arbitrarily chosen. We aimed to identify an optimal cut-off and timing for a proprietary high-sensitivity cardiac troponin I (hs-cTnI) assay to facilitate post-operative clinical decision-making. METHODS AND RESULTS: We performed a retrospective analysis of all patients undergoing elective isolated CABG at our centre between January 2013 and May 2019. Of 4684 consecutive patients, 161 patients (3.48%) underwent invasive coronary angiography after surgery, of whom 86 patients (53.4%) underwent repeat revascularization. We found an optimal cut-off value for peak hs-cTnI of >13 000 ng/L [>500× the upper reference limit (URL)] to be significantly associated with repeat revascularization within 48 h after surgery, which was internally validated through random repeated sampling with 1000 iterations. The same cut-off also predicted 30-day major adverse cardiovascular events and all-cause mortality after a median follow-up of 3.1 years, which was validated in an external cohort. A decision tree analysis of serial hs-cTnI measurements showed no added benefit of hs-cTnI measurements in patients with electrocardiographic or echocardiographic abnormalities or haemodynamic instability. Likewise, early post-operative hs-cTnI elevations had a low yield for clinical decision-making and only later elevations (at 12-16 h post-operatively) using a threshold of 8000 ng/L (307× URL) were significantly associated with repeat revascularization with an area under the curve of 0.92 (95% confidence interval 0.88-0.95). CONCLUSION: Our data suggest that for hs-cTnI, higher cut-offs than currently recommended should be used in the post-operative management of patients following CABG.

The use of high-sensitivity cardiac troponin T and creatinine kinase-MB as a prognostic markers in patients with acute myocardial infarction and chronic kidney disease.

Background: High-sensitivity cardiac troponin T (hs-cTnT) and creatine kinase (CK)-MB are the most commonly used biomarkers for the diagnosis and prognosis of acute myocardial infarction (AMI). Chronic kidney disease (CKD) often leads to elevated hs-cTnT levels in non-AMI patients. However, studies comparing the prognostic value of both hs-cTnT and CK-MB in patients with AMI and CKD are lacking.Methods: We conducted a retrospective study on AMI patients diagnosed between January 2015 and October 2020. Patients were categorized based on renal function as normal or CKD. Peak hs-cTnT and CK-MB levels during hospitalization were collected, and their diagnostic value was evaluated using receiver operating characteristic (ROC) curves. The impact on in-hospital mortality was analyzed using multivariate logistic regression. The relationship between the hs-cTnT/CK-MB ratio and in-hospital death was examined using a restricted cubic spline (RCS) curve.Results: The study included 5022 AMI patients, of whom 797 (15.9%) had CKD. The AUCs of Hs-cTnT and CK-MB were higher in the CKD group [0.842 (95% CI: 0.789-0.894) and 0.821 (95% CI: 0.760-0.882)] than in the normal renal function group [0.695 (95% CI: 0.604-0.790) and 0.708 (95% CI: 0.624-0.793)]. After full adjustment for all risk factors, hs-cTnT (OR, 2.82; 95% CI, 1.03-9.86; p = 0.038) and CK-MB (OR, 4.91; 95% CI, 1.54-14.68; p = 0.007) above the cutoff values were independent predictors of in-hospital mortality in patients with CKD. However, in patients with normal renal function, only CK-MB above the cutoff (OR, 2.45; 95% CI, 1.02-8.24; p = 0.046) was a predictor of in-hospital mortality, whereas hs-cTnT was not. There was an inverted V-shaped relationship between the hs-cTnT/CK-MB ratio and in-hospital mortality, with an inflection point of 19.61. The ratio within the second quartile (9.63-19.6) was an independent predictor of in-hospital mortality in patients with CKD (OR 5.3, 95% CI 1.66-16.86, p = 0.005).Conclusions: Hs-cTnT independently predicted in-hospital mortality in AMI patients with CKD, whereas its predictive value was not observed in patients with normal renal function. CK-MB was an independent predictor of in-hospital mortality regardless of renal function. Moreover, the hs-cTnT/CK-MB ratio may aid in risk stratification of AMI patients with CKD.

Myocardial injury defined as elevated high-sensitivity cardiac troponin T is associated with higher mortality in patients seeking care at emergency departments with acute dyspnea.

BACKGROUND: Elevated levels of cardiac troponin T has been observed in patients seeking care at the emergency department (ED) presenting with chest pain but without myocardial infarction (MI). The clinical importance of this observation remains, however, still unclear. Our main aim was to study the role of cardiac troponin T in patients admitted to the emergency department with acute dyspnea, a group of patients with a high cardiovascular comorbidity, but no primary acute MI. POPULATION AND METHODS: Patients from the age of 18 seeking care at the ED for dyspnea, without an acute cardiac syndrome, and with a recorded assessment of high-sensitivity cardiac troponin T (hs-cTnT), were included (n = 1001). Patients were categorized into 3 groups by hs-cTnT level, i.e. <15, 15-100 and > 100 µg/l. Cox regression with Hazard Ratios (HRs) and 95% Confidence Intervals (CI) for 3-months mortality was performed, with adjustment for sex, age, respiratory frequency, saturation, CHF, renal disease, and BMI. RESULTS: Fully adjusted HRs (95% CI) for 3-month mortality, with hs-cTnT < 15 µg/l as reference level, showed for hs-cTnT 15-100 a HR of 3.682 (1.729-7.844), and for hs-cTnT > 100 a HR of 10.523 (4.465-24.803). CONCLUSION: Elevated hs-cTnT seems to be a relevant marker of poor prognosis in patients with acute dyspnea without MI and warrants further validation and clinical testing.