scholarly journals What to do when you question cardiac troponin values

2017 ◽  
Vol 7 (6) ◽  
pp. 577-586 ◽  
Author(s):  
Johannes Mair ◽  
Bertil Lindahl ◽  
Christian Müller ◽  
Evangelos Giannitsis ◽  
Kurt Huber ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
Troponin T ◽  
High Sensitivity ◽  
Daily Routine ◽  
Analytical Sensitivity ◽  
Test Results ◽  
False Positive Test ◽  
The Cost ◽  
High Degree

High-sensitivity cardiac troponin assays enable cardiac troponin measurement with a high degree of analytical sensitivity and a low level of analytical imprecision at the low measuring range. One of the most important advantages of these new assays is that they allow novel, more rapid approaches for ruling in or ruling out acute myocardial infarctions. The increase in the early diagnostic sensitivity of high-sensitivity cardiac troponin assays comes at the cost of a reduced acute myocardial infarction specificity of the biomarker, because more patients with other causes of acute or chronic myocardial injury without overt myocardial ischaemia are detected than with previous cardiac troponin assays. Increased troponin concentrations that do not fit with the clinical presentation are seen in the daily routine, mainly as a result of a variety of pathologies, and if tested in the same sample, even discrepancies between high-sensitivity cardiac troponin I and troponin T test results may sometimes be found as well. In addition, analytically false-positive test results occasionally may occur since no assay is perfect. In this review, we summarise the biochemical, pathophysiological and analytical background of the work-up for such a clinical setting.

scholarly journals Is high-sensitivity troponin, alone or in combination with copeptin, sensitive enough for ruling out NSTEMI in very early presenters at admission? A post hoc analysis performed in emergency departments

BMJ Open ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. e023994 ◽  
Author(s):  
Camille Chenevier-Gobeaux ◽  
Mustapha Sebbane ◽  
Christophe Meune ◽  
Sophie Lefebvre ◽  
Anne-Marie Dupuy ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
Troponin T ◽  
False Negative ◽  
High Sensitivity ◽  
Threshold Value ◽  
St Segment Elevation ◽  
Post Hoc Analysis ◽  
Registration Number ◽  
Post Hoc

ObjectivesCopeptin and high-sensitivity cardiac troponin (HS-cTn) assays improve the early detection of non-ST-segment elevation myocardial infarction (NSTEMI). Their sensitivities may, however, be reduced in very early presenters.SettingWe performed a post hoc analysis of three prospective studies that included patients who presented to the emergency department for chest pain onset (CPO) of less than 6 hours.Participants449 patients were included, in whom 12% had NSTEMI. CPO occurred <2 hours from ED presentation in 160, between 2 and 4 hours in 143 and >4 hours in 146 patients. The prevalence of NSTEMI was similar in all groups (9%, 13% and 12%, respectively, p=0.281).MeasuresDiagnostic performances of HS-cTn and copeptin at presentation were examined according to CPO. The discharge diagnosis was adjudicated by two experts, including cardiac troponin I (cTnI). HS-cTn and copeptin were blindly measured.ResultsDiagnostic accuracies of cTnI, cTnI +copeptin and HS-cardiac troponin T (HS-cTnT) (but not HS-cTnT +copeptin) lower through CPO categories. For patients with CPO <2 hours, the choice of a threshold value of 14 ng/L for HS-cTnT resulted in three false negative (Sensitivity 80%(95% CI 51% to 95%); specificity 85% (95% CI 78% to 90%); 79% of correctly ruled out patients) and that of 5 ng/L in two false negative (sensitivity 87% (95% CI 59% to 98%); specificity 58% (95% CI 50% to 66%); 52% of correctly ruled out patients). The addition of copeptin to HS-cTnT induced a decrease of misclassified patients to 1 in patients with CPO <2 hours (sensitivity 93% (95% CI 66% to 100%); specificity 41% (95% CI 33% to 50%)).ConclusionA single measurement of HS-cTn, alone or in combination with copeptin at admission, seems not safe enough for ruling out NSTEMI in very early presenters (with CPO <2 hours).Trial registration numberDC-2009–1052

Kinetics of high-sensitivity cardiac troponin T or troponin I compared to creatine kinase in patients with revascularized acute myocardial infarction

2015 ◽  
Vol 53 (5) ◽  
Author(s):  
Kamila Solecki ◽  
Anne Marie Dupuy ◽  
Nils Kuster ◽  
Florence Leclercq ◽  
Richard Gervasoni ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Troponin T ◽  
High Sensitivity ◽  
Cardiac Troponin T ◽  
Significant Difference ◽  
Kinetics Of

AbstractCardiac biomarkers are the cornerstone of the biological definition of acute myocardial infarction (AMI). The key role of troponins in diagnosis of AMI is well established. Moreover, kinetics of troponin I (cTnI) and creatine kinase (CK) after AMI are correlated to the prognosis. New technical assessment like high-sensitivity cardiac troponin T (hs-cTnT) raises concerns because of its unclear kinetic following the peak. This study aims to compare kinetics of cTnI and hs-cTnT to CK in patients with large AMI successfully treated by percutaneous coronary intervention (PCI).We prospectively studied 62 patients with anterior AMI successfully reperfused with primary angioplasty. We evaluated two consecutive groups: the first one regularly assessed by both CK and cTnI methods and the second group by CK and hs-cTnT. Modeling of kinetics was realized using mixed effects with cubic splines.Kinetics of markers showed a peak at 7.9 h for CK, at 10.9 h (6.9–12.75) for cTnI and at 12 h for hs-cTnT. This peak was followed by a nearly log linear decrease for cTnI and CK by contrast to hs-cTnT which appeared with a biphasic shape curve marked by a second peak at 82 h. There was no significant difference between the decrease of cTnI and CK (p=0.63). CK fell by 79.5% (76.1–99.9) vs. cTnI by 86.8% (76.6–92.7). In the hs-cTnT group there was a significant difference in the decrease by 26.5% (9–42.9) when compared with CK that fell by 79.5% (64.3–90.7).Kinetic of hs-cTnT and not cTnI differs from CK. The role of hs-cTnT in prognosis has to be investigated.

scholarly journals No additional value of conventional and high-sensitivity cardiac troponin over clinical scoring systems in the differential diagnosis of type 1 vs. type 2 myocardial infarction

2018 ◽  
Vol 56 (5) ◽  
pp. 702-709 ◽  
Author(s):  
Luciano Consuegra-Sánchez ◽  
Juan José Martínez-Díaz ◽  
Luis García de Guadiana-Romualdo ◽  
Samantha Wasniewski ◽  
Patricia Esteban-Torrella ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Troponin T ◽  
Characteristic Curve ◽  
High Sensitivity ◽  
St Segment ◽  
Clinical Scoring

AbstractBackground:The distinction of type 1 and type 2 myocardial infarction (MI) is of major clinical importance. Our aim was to evaluate the diagnostic ability of absolute and relative conventional cardiac troponin I (cTnI) and high-sensitivity cardiac troponin T (hs-cTnT) in the distinction between type 1 and type 2 MI in patients presenting at the emergency department with non-ST-segment elevation acute chest pain within the first 12 h.Methods:We measured cTnI (Dimension Vista) and hs-cTnT (Cobas e601) concentrations at presentation and after 4 h in 200 patients presenting with suspected acute MI. The final diagnosis, based on standard criteria, was adjudicated by two independent cardiologists.Results:One hundred and twenty-five patients (62.5%)were classified as type 1 MI and 75 (37.5%) were type 2 MI. In a multivariable setting, age (relative risk [RR]=1.43, p=0.040), male gender (RR=2.22, p=0.040), T-wave inversion (RR=8.51, p<0.001), ST-segment depression (RR=8.71, p<0.001) and absolute delta hs-cTnT (RR=2.10, p=0.022) were independently associated with type 1 MI. In a receiver operating characteristic curve analysis, the discriminatory power of absolute delta cTnI and hs-cTnT was significantly higher compared to relative c-TnI and hs-cTnT changes. The additive information provided by cTnI and hs-cTnT over and above the information provided by the “clinical” model was only marginal.Conclusions:The diagnostic information provided by serial measurements of conventional or hs-cTnT is not better than that yielded by a simple clinical scoring model. Absolute changes are more informative than relative troponin changes.

scholarly journals Moderate elevations of high-sensitivity cardiac troponin I and B-type natriuretic peptide in chronic hemodialysis patients are associated with mortality

2013 ◽  
Vol 51 (6) ◽  
Author(s):  
Daniël A. Geerse ◽  
Miranda van Berkel ◽  
Steffie Vogels ◽  
Jeroen P. Kooman ◽  
Constantijn J.A.M. Konings ◽  
...  
Keyword(s):  
Natriuretic Peptide ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Troponin T ◽  
Total Mortality ◽  
High Sensitivity ◽  
Hemodialysis Patients ◽  
Chronic Hemodialysis ◽  
Cardiac Troponin I ◽  
Moderate Elevation

AbstractSeveral biomarkers are associated with mortality in hemodialysis patients. In particular, elevated cardiac troponin T and B-type natriuretic peptide (BNP) are strong predictors of mortality; however, less is known about cardiac troponin I (cTnI). Elevated troponin I is detected in many hemodialysis patients, but the association of moderate elevations with mortality is unclear.The relation between mortality and cTnI, using a high-sensitivity cTnI assay, as well as BNP and C-reactive protein (CRP) was evaluated in 206 chronic hemodialysis patients.Median follow-up was 28 months with a total mortality of 35%. Mortality was significantly associated with elevated cTnI, BNP and CRP. Even patients with only moderate elevation of cTnI (0.01–0.10 μg/L) showed 2.5-fold increased mortality. Interestingly, hazard ratios for mortality for single (random) measurements were comparable to those for mean/median measurements. Subsequently, subgroup analysis based on combined markers was performed. Patients with both cTnI <0.01 μg/L and BNP in the first quartile had 100% survival. Patients with either cTnI <0.01 μg/L or BNP in the lowest quartile had significantly lower mortality (12% and 13%, respectively) than patients with BNP levels in the second quartile or higher and cTnI of 0.01–0.05 μg/L and patients with cTnI ≥0.05 μg/L (mortality 46 and 58%, respectively).A combination of moderate elevation of cTnI and BNP provided additional prognostic value. A single measurement of these biomarkers performed comparably to the mean/median of multiple measurements.

Evaluation of analytical performance of a new high-sensitivity immunoassay for cardiac troponin I

2018 ◽  
Vol 56 (3) ◽  
pp. 492-501 ◽  
Author(s):  
Silvia Masotti ◽  
Concetta Prontera ◽  
Veronica Musetti ◽  
Simona Storti ◽  
Rudina Ndreu ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
High Sensitivity ◽  
Cardiac Troponin I ◽  
Analytical Performance ◽  
Analytical Sensitivity ◽  
Plasma Samples ◽  
Serum Samples ◽  
Significant Difference ◽  
Heparin Plasma

AbstractBackground:The study aim was to evaluate and compare the analytical performance of the new chemiluminescent immunoassay for cardiac troponin I (cTnI), called Access hs-TnI using DxI platform, with those of Access AccuTnI+3 method, and high-sensitivity (hs) cTnI method for ARCHITECT platform.Methods:The limits of blank (LoB), detection (LoD) and quantitation (LoQ) at 10% and 20% CV were evaluated according to international standardized protocols. For the evaluation of analytical performance and comparison of cTnI results, both heparinized plasma samples, collected from healthy subjects and patients with cardiac diseases, and quality control samples distributed in external quality assessment programs were used.Results:LoB, LoD and LoQ at 20% and 10% CV values of the Access hs-cTnI method were 0.6, 1.3, 2.1 and 5.3 ng/L, respectively. Access hs-cTnI method showed analytical performance significantly better than that of Access AccuTnI+3 method and similar results to those of hs ARCHITECT cTnI method. Moreover, the cTnI concentrations measured with Access hs-cTnI method showed close linear regressions with both Access AccuTnI+3 and ARCHITECT hs-cTnI methods, although there were systematic differences between these methods. There was no difference between cTnI values measured by Access hs-cTnI in heparinized plasma and serum samples, whereas there was a significant difference between cTnI values, respectively measured in EDTA and heparin plasma samples.Conclusions:Access hs-cTnI has analytical sensitivity parameters significantly improved compared to Access AccuTnI+3 method and is similar to those of the high-sensitivity method using ARCHITECT platform.

scholarly journals Susceptibility of Cardiac Troponin Assays to Biotin Interference

2019 ◽  
Vol 151 (5) ◽  
pp. 486-493 ◽  
Author(s):  
Ithiel J Frame ◽  
Parag H Joshi ◽  
Caroline Mwangi ◽  
Ian Gunsolus ◽  
James A De Lemos ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
Troponin T ◽  
Plasma Concentrations ◽  
High Sensitivity ◽  
Over The Counter ◽  
Agarose Beads ◽  
Spiked Plasma ◽  
Missed Diagnosis ◽  
Biotin Supplementation

Abstract Objectives To investigate biotin interference on three cardiac troponin (cTn) assays and demonstrate a method to overcome biotin interference. Methods cTn levels were measured in (1) plasma from healthy volunteers on 10-mg daily biotin supplementation mixed with a plasma with known elevated troponin, (2) plasmas with known elevated cTn after mixing in reagent biotin to simulate supplementation, and (3) biotin-spiked plasma specimens pretreated with streptavidin-agarose beads. Results Daily biotin ingestion (10 mg) and studies simulating daily biotin use resulted in significant interference in the Gen5 cardiac troponin T (cTnT) assay; the contemporary Gen 4 cTnT and high-sensitivity cardiac troponin I (hs-cTnI) assays were unaffected. The biotin interference threshold was 31, 315, and more than 2,000 ng/mL for Gen5 cTnT, cTnT, and hs-cTnI assays, respectively. Streptavidin pretreatment blocked biotin interference in cTn assays. Conclusions Biotin interference is possible at plasma concentrations achievable by ingestion of over-the-counter supplements that may lead to delayed or missed diagnosis of myocardial injury with the Gen5 cTnT assay.

scholarly journals Economic Considerations of Early Rule-In/Rule-Out Algorithms for The Diagnosis of Myocardial Infarction in The Emergency Department Using Cardiac Troponin and Glycemic Biomarkers

2017 ◽  
Vol 63 (2) ◽  
pp. 593-602 ◽  
Author(s):  
Colleen Shortt ◽  
Feng Xie ◽  
Richard Whitlock ◽  
Jinhui Ma ◽  
Natasha Clayton ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Emergency Department ◽  
Cardiac Troponin ◽  
Troponin I ◽  
High Sensitivity ◽  
Cost Effective ◽  
Coronary Syndrome ◽  
Hb A1c ◽  
The Cost ◽  
Rule Out

Abstract BACKGROUND We have previously demonstrated the utility of a rule-in/rule-out strategy for myocardial infarction (MI) using glycemic biomarkers in combination with cardiac troponin in the emergency department (ED). Given that the cost of assessing patients with possible MI in the ED is increasing, we sought to compare the health services cost of our previously identified early rule-in/rule-out approaches for MI among patients who present to the ED with symptoms suggestive of acute coronary syndrome (ACS). METHODS We compared the cost differences between different rule-in/rule-out strategies for MI using presentation cardiac troponin I (cTnI), high-sensitivity cTnI (hs-cTnI), high-sensitivity cardiac troponin T (hs-cTnT), glucose, and/or hemoglobin A1c (Hb A1c) in 1137 ED patients (7-day MI n = 133) as per our previously defined algorithms and compared them with the European Society of Cardiology (ESC) 0-h algorithm-cutoffs. Costs associated with each decision model were obtained from site-specific sources (length of stay) and provincial sources (Ontario Case Costing Initiative). RESULTS Algorithms incorporating cardiac troponin and glucose for early rule-in/rule-out were the most cost effective and clinically safest methods (i.e., ≤1 MI missed) for early decision making, with hs-cTnI and glucose yielding lower costs compared to cTnI and glucose, despite the higher price for the hs-cTnI test. The addition of Hb A1c to the algorithms increased the cost of these algorithms but did not miss any additional patients with MI. Applying the ESC 0-h algorithm-cutoffs for hs-cTnI and hs-cTnT were the most costly. CONCLUSIONS Rule-in/rule-out algorithms incorporating presentation glucose with high-sensitivity cardiac troponin are the safest and most cost-effective options as compared to the ESC 0-h algorithm-cutoffs.

scholarly journals Signal Enhancement in Oriented Immunosorbent Assays: A Balance between Accessibility of Antigen Binding Sites and Avidity

Biosensors ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 493
Author(s):  
Vanessa Susini ◽  
Vanna Fierabracci ◽  
Gaia Barria ◽  
Lisa Dodoli ◽  
Laura Caponi ◽  
...  
Keyword(s):  
Steric Hindrance ◽  
Binding Sites ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Specific Antigen ◽  
High Sensitivity ◽  
Antigen Binding ◽  
Analytical Sensitivity ◽  
Experimental Setting ◽  
Better Than

The sensitivity of immunoassays was reported to be increased by the orientation of antibodies. We investigated how the size and valence of antigens and orientation and valence of antibodies contribute to the analytical sensitivity of ELISA. Antigens differing in size and number of epitopes were compared using oriented and non-oriented ELISAs: the orientation of antibodies was obtained coating half-fragment antibodies on maleimide microplates, while, in non-oriented ELISA, whole antibodies were randomly physisorbed. The oriented assay performed better than the non-oriented one at each concentration (0.4–3.3 ng/mL) of a small monomeric antigen (cardiac Troponin I, 24 kDa, Rh 3 nm). No significant differences were observed with a large monovalent antigen (prostate-specific antigen-alpha(1) antichymotrypsin, 90 kDa, Rh > 3 nm), since its steric hindrance overcame the increased availability of antigen binding sites given by orientation. Large multivalent antigens (ferritin, 280 kDa, Rh 6 nm; α-fetoprotein, >70 kDa, Rh > 3.3 nm) performed better in non-oriented assays. In this case, the repeated epitopes on the surface of the antigens favored the engagement of both antigen binding sites of the whole IgG, thus suggesting that avidity represented the leading force in this experimental setting. In conclusion, the design of high-sensitivity ELISAs should consider the dimension and valency of antigens in addition to the affinity and avidity of antibodies.

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