Evaluation of the Atellica TnIH cardiac troponin I assay and assessment of biological equivalence

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Carel J. Pretorius ◽  
William Parsonage ◽  
Louise W. Cullen ◽  
Urs Wilgen ◽  
Elzahn De Waal ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
De Novo ◽  
Limit Of Detection ◽  
Underlying Mechanism ◽  
Specific Reference ◽  
Detection Capability ◽  
Analytical Accuracy ◽  
Good Agreement

Abstract Objectives We evaluated the analytical performance characteristics and the biological equivalence of the Atellica TnIH assay. Methods Precision, detection capability, linearity, and sex specific 99th percentiles were determined de novo. Classification of patients relative to the 99th percentiles was used to assess biological equivalence. Results Analytical precision and detection capability of the Atellica TnIH assay is excellent with a limit of blank <1 ng/L and 62.5% of women and 93% of men had results above the limit of detection. The 99th percentiles (90% CI) in women were 49 ng/L (31–67) and 70 ng/L (48–121) in men. An asymmetrical distribution involving 5% of results was notable. Agreement was moderate (Kappa 0.58, 95% CI 0.53–0.63) with 20% of patients discordantly classified with Atellica TnIH below and Access hsTnI above the 99th percentiles. Serial results in 195 patients demonstrated good agreement (Kappa 0.84, 95% CI 0.77–0.90). Differences greater than the assay specific reference change values (z≥±1.96) occurred in 65% (95% CI 53–76%) of 99th percentile discordant patients compared to 2.7% (p<0.001) and 76% (p=0.17) of the concordant low and high cTnI groups respectively. Conclusions The 99th percentile discordant and the concordantly elevated groups are more alike with respect to their z≥±1.96 rates. This favours an overestimated Atellica TnIH 99th percentile as more likely, and we hypothesize that antibody interference resulting in asymmetric scatter of nearly 5% samples may be the underlying mechanism. Analytical accuracy and interferences in cardiac troponin assays should be investigated and resolved with high priority.

Analytical assessment of ortho clinical diagnostics high-sensitivity cardiac troponin I assay

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Peter A. Kavsak ◽  
Tara Edge ◽  
Chantele Roy ◽  
Paul Malinowski ◽  
Karen Bamford ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
Limit Of Detection ◽  
Clinical Performance ◽  
Characteristic Curve ◽  
Area Under The Curve ◽  
High Sensitivity ◽  
Cardiac Troponin I ◽  
Clinical Diagnostics ◽  
Ortho Clinical Diagnostics

AbstractObjectivesTo analytically evaluate Ortho Clinical Diagnostics VITROS high-sensitivity cardiac troponin I (hs-cTnI) assay in specific matrices with comparison to other hs-cTn assays.MethodsThe limit of detection (LoD), imprecision, interference and stability testing for both serum and lithium heparin (Li-Hep) plasma for the VITROS hs-cTnI assay was determined. We performed Passing-Bablok regression analyses between sample types for the VITROS hs-cTnI assay and compared them to the Abbott ARCHITECT, Beckman Access and the Siemens ADVIA Centaur hs-cTnI assays. We also performed Receiver-operating characteristic curve analyses with the area under the curve (AUC) determined in an emergency department (ED)-study population (n=131) for myocardial infarction (MI).ResultsThe VITROS hs-cTnI LoD was 0.73 ng/L (serum) and 1.4 ng/L (Li-Hep). Stability up to five freeze-thaws was observed for the Ortho hs-cTnI assay, with the analyte stability at room temperature in serum superior to Li-Hep with gross hemolysis also affecting Li-Hep plasma hs-cTnI results. Comparison of Li-Hep to serum concentrations (n=202), yielded proportionally lower concentrations in plasma with the VITROS hs-cTnI assay (slope=0.85; 95% confidence interval [CI]:0.83–0.88). In serum, the VITROS hs-cTnI concentrations were proportionally lower compared to other hs-cTnI assays, with similar slopes observed between assays in samples frozen <−70 °C for 17 years (ED-study) or in 2020. In the ED-study, the VITROS hs-cTnI assay had an AUC of 0.974 (95%CI:0.929–0.994) for MI, similar to the AUCs of other hs-cTn assays.ConclusionsLack of standardization of hs-cTnI assays across manufacturers is evident. The VITROS hs-cTnI assay yields lower concentrations compared to other hs-cTnI assays. Important differences exist between Li-Hep plasma and serum, with evidence of stability and excellent clinical performance comparable to other hs-cTn assays.

scholarly journals Fluorescence Based on Surface Plasmon Coupled Emission for Ultrahigh Sensitivity Immunoassay of Cardiac Troponin I

Biomedicines ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 448
Author(s):  
Vien Thi Tran ◽  
Heongkyu Ju
Keyword(s):  
Surface Plasmon ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Limit Of Detection ◽  
Delayed Diagnosis ◽  
Cardiac Troponin I ◽  
Quantitative Detection ◽  
Fluorescence Signal ◽  
Label Free ◽  
Ultrahigh Sensitivity

This work demonstrates the quantitative assay of cardiac Troponin I (cTnI), one of the key biomarkers for acute cardiovascular diseases (the leading cause of death worldwide) using the fluorescence-based sandwich immune reaction. Surface plasmon coupled emission (SPCE) produced by non-radiative coupling of dye molecules with surface plasmons being excitable via the reverse Kretschmann format is exploited for fluorescence-based sandwich immunoassay for quantitative detection of cTnI. The SPCE fluorescence chip utilizes the gold (2 nm)-silver (50 nm) bimetallic thin film, with which molecules of the dye Alexa 488 (conjugated with detection antibodies) make a near field coupling with the plasmonic film for SPCE. The experimental results find that the SPCE greatly improves the sensitivity via enhancing the fluorescence signal (up to 50-fold) while suppressing the photo-bleaching, permitting markedly enhanced signal-to-noise ratio. The limit of detection of 21.2 ag mL−1 (atto-gram mL−1) is obtained, the lowest ever reported to date amid those achieved by optical technologies such as luminescence and label-free optical sensing techniques. The features discovered such as ultrahigh sensitivity may prompt the presented technologies to be applied for early diagnosis of cTnI in blood, particularly for emergency medical centers overloaded with patients with acute myocardial infarction who would suffer from time-delayed diagnosis due to insufficient assay device sensitivity.

Abstract 16517: Atrial Natriuretic Peptide as a Marker for Early Rule-Out of Acute Myocardial Infarction

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Anna Slagman ◽  
Julia Searle ◽  
Fabian Holert ◽  
Jörn Ole Vollert ◽  
Reinhold Muller ◽  
...  
Keyword(s):  
Emergency Department ◽  
Gold Standard ◽  
Cardiac Troponin ◽  
Roc Analysis ◽  
Troponin I ◽  
Limit Of Detection ◽  
Normal Population ◽  
Area Under The Curve ◽  
Chief Complaints ◽  
Rule Out

Introduction: Mid-regional pro-ANP is mainly synthesized in the atria of the heart and it′s secretion is stimulated by ischemia and distension of the myocardium. Objective: To assess the utility of ANP for rule out NSTEMI in combination with cardiac troponin in unselected patients who attend the Emergency Department (ED) with acute cardiac chief complaints. Methods: Patients with chest pain and dyspnea were enrolled over a period of 30 months in the Emergency Department (n=537). Patients with STEMI were excluded from the analysis as diagnosis is ECG- and not biomarker-based (n=18). Blood samples were drawn within 2 hours after admission. Gold-Standard diagnoses were adjudicated by an independent cardiologist. ANP was measured using the BRAHMS Kryptor MR-proANP assay. The lower limit of detection is 2.1 pmol/l. The 97.5 th percentile of a normal population is 86.2 pmol/l and was applied as a cut-off value in this analysis. Troponin I was measured using the Stratus CS and a cut-off value of 0.1 μg/L was applied. Variables are shown as median (IQR) and 95%-CIs. Results: The median ANP-value in all patients (n=519) was 135 pmol/l. Patients with NSTEMI (n=58) had significantly higher ANP-values (244/104-350 pmol/l) as compared to patients with other diagnoses (126/74-256; p<0.0001). In ROC-analysis ANP had an area under the curve of 0.648 (CI:0.582-0.715) for the diagnosis of NSTEMI. Of all patients, 74.2% were troponin negative at admission (n=385). Of these patients, 32.2% (n=124) were also ANP negative. The prevalence of AMI in this subgroup was 1.6% (n=2). The NPV for the combination of troponin and ANP was 98.4% (CI: 94.3-99.8%) and thus higher than for both markers alone (figure 1). In combination with Copeptin, the NPV increased to 100% (CI: 96.3-100%). Conclusions: ANP has potential for early rule-out of AMI in combination with troponin and, due to a different pathophysiological stimulus, it might be used as part of a triple-marker strategy with copeptin and troponin.

Assessing matrix, interferences and comparability between the Abbott Diagnostics and the Beckman Coulter high-sensitivity cardiac troponin I assays

2018 ◽  
Vol 56 (7) ◽  
pp. 1176-1181 ◽  
Author(s):  
Peter A. Kavsak ◽  
Paul Malinowski ◽  
Chantele Roy ◽  
Lorna Clark ◽  
Shana Lamers
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
Matrix Effects ◽  
Limit Of Detection ◽  
High Sensitivity ◽  
Mean Difference ◽  
Plasma Samples ◽  
Matrix Interferences ◽  
Heparin Plasma ◽  
Edta Plasma

Abstract Background: Analytical evaluation of high-sensitivity cardiac troponin (hs-cTn) assays, with particular attention to imprecision, interferences and matrix effects, at normal cTn concentrations, is of utmost importance as many different clinical algorithms use concentration cutoffs <10 ng/L for decision-making. The objective for the present analytical study was to compare the new Beckman Coulter hs-cTnI assay (Access hsTnI) to Abbott’s hs-cTnI assay in different matrices and for different interferences, with a focus on concentrations <10 ng/L. Methods: The limit of blank (LoB) and the limit of detection (LoD) were determined in different matrices for the Beckman hs-cTnI assay. Passing-Bablok regression and difference plots were determined for 200 matched lithium heparin and EDTA plasma samples for the Beckman assay and 200 lithium heparin samples for the Abbott assay. Both EDTA and heparin plasma samples were also evaluated for stability under refrigerated conditions, for endogenous alkaline phosphatase interference and for hemolysis and icterus. Results: The Beckman hs-cTnI assay LoB was 0.5 ng/L with the following range of LoDs=0.8–1.2 ng/L, with EDTA plasma yielding lower concentrations as compared to lithium heparin plasma (mean difference=−14.9%; 95% CI=−16.9 to 12.9). Below 10 ng/L, lithium heparin cTnI results from the Beckman assay were on average 1.1 ng/L (95% CI=0.7 to 1.5) higher than the Abbott results, with no difference between the methods when using EDTA plasma (mean difference =−0.1 ng/L; 95% CI=−0.3 to 0.2). Low cTnI concentrations were less effected by interferences in EDTA plasma. Conclusions: The Access hsTnI method can reliably detect normal cTnI concentrations with both lithium heparin and EDTA plasma being suitable matrices.

Analytical evaluation of the new Beckman Coulter Access high sensitivity cardiac troponin I immunoassay

2017 ◽  
Vol 56 (1) ◽  
Author(s):  
Giuseppe Lippi ◽  
Anna Ferrari ◽  
Giorgio Gandini ◽  
Matteo Gelati ◽  
Claudia Lo Cascio ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
Limit Of Detection ◽  
High Sensitivity ◽  
Cardiac Troponin I ◽  
Analytical Performance ◽  
The Novel ◽  
Reference Limit ◽  
Automated Immunoassay ◽  
Upper Reference Limit

AbstractBackground:This study was aimed to evaluate the analytical performance of the novel chemiluminescent and fully-automated Beckman Coulter Access hsTnI high-sensitivity immunoassay for measurement of cardiac troponin I (cTnI).Methods:The study, using lithium heparin samples, included assessment of limit of blank (LOB), limit of detection (LOD), functional sensitivity, linearity, imprecision (within run, between-run and total), calculation of 99th percentile upper reference limit (URL) in 175 healthy blood donors (mean age, 36±12 years; 47% women) and comparison with two other commercial cTnI immunoassays.Results:The LOB, LOD and functional sensitivity of Access hsTnI were 0.14, 0.34 and 1.35 ng/L, respectively. The within-run, between-run and total imprecision was 2.2%–2.9%, 4.6%–5.4%, and 5.4%–6.1%, respectively. The linearity was excellent in the range of cTnI values between 0.95 and 4195 ng/L (r=1.00). The 99th percentile URL was 15.8 ng/L. Measurable cTnI values were found in 173/175 healthy subjects (98.9%). Good agreement of cTnI values was found with AccuTnI+3 (r=0.97; mean bias, −9.3%), whereas less satisfactory agreement was found with Siemens Dimension Vista cTnI (r=0.95; mean bias, −55%).Conclusions:The results of our evaluation of the Beckman Coulter Access hsTnI indicate that the analytical performance of this fully-automated immunoassay is excellent.

scholarly journals Analytical validation of a highly sensitive point-of-care system for cardiac troponin I determination

2019 ◽  
Vol 58 (1) ◽  
pp. 138-145 ◽  
Author(s):  
Federica Braga ◽  
Elena Aloisio ◽  
Andrea Panzeri ◽  
Takahito Nakagawa ◽  
Mauro Panteghini
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
Limit Of Detection ◽  
Clinical Performance ◽  
Point Of Care ◽  
Total Error ◽  
Method Comparison ◽  
Reference Limit ◽  
Highly Sensitive ◽  
Limit Of Quantitation

Abstract Background Highly sensitive cardiac troponin assays (hs-cTn) are not available as point-of-care (POC) measurements. As rapid testing cannot be achieved at the expense of clinical performance, there is an urgent need to develop and rigorously validate POC hs-cTn. Konica Minolta (KM) has recently developed a surface plasmon-field enhanced fluorescence spectroscopy-based POC hs-cTn I system. Methods We validated the analytical characteristics of the KM POC system according to the international guidelines. Results Limit of blank (LoB) and limit of detection (LoD) were 0.35 and 0.62 ng/L, respectively, hs-cTn I concentrations corresponding to a total CV of 20%, 10% and 5% were 1.5, 3.9 and 11.0 ng/L, respectively. Method comparison studies showed that KM calibration was successfully traced to higher-order references. Limit of quantitation (LoQ), i.e. the hs-cTn I concentration having a total error of measurement of ≤34%, was 10.0 ng/L. The upper reference limit (URL) for 600 healthy blood donors was calculated at 12.2 ng/L (90% confidence interval [CI]: 9.2–39.2), while sex-partitioned URLs were 20.6 (males) and 10.7 ng/L (females), respectively (p < 0.0001). KM assay measured hs-cTn I concentrations >LoD in 65.7% of all reference individuals, in 76.7% of males and in 54.7% of females, respectively. Conclusions The KM system joins the characteristics of POC systems to the analytical performance of hs-cTn.

Potential impact of a novel pathway for suspected myocardial infarction utilising a new high-sensitivity cardiac troponin I assay

2021 ◽  
pp. emermed-2020-210812
Author(s):  
Rob Meek ◽  
Louise Cullen ◽  
Zhong Xian Lu ◽  
Arthur Nasis ◽  
Lisa Kuhn ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Limit Of Detection ◽  
High Sensitivity ◽  
Routine Care ◽  
Primary Objective ◽  
Cardiac Troponin I ◽  
Post Discharge ◽  
Reference Limit

BackgroundHigh-sensitivity cardiac troponin I (hs-cTnI) assays promise high diagnostic accuracy for myocardial infarction (MI). In an ED where conventional cTnI was in use, we evaluated an assessment pathway using the new Access hsTnI assay.MethodsThis retrospective analysis recruited ED patients with suspected MI between June and September 2019. All patients received routine care with a conventional cTnI assay (AccuTnI +3: limit of detection (LoD) 10 ng/L, 99th centile upper reference limit (URL) 40 ng/L, abnormal elevation cut-point 80 ng/L). Arrival, then 90-minute or 360-minute cTnI levels for low and non-low risk patients, respectively (ED Assessment of Chest pain score) guided diagnosis and disposition which was at treating physician discretion. The same patients had arrival and 90-minute or 180-minute samples drawn for hs-cTnI levels (Access hsTnI: LoD 2 ng/L, 99th centile URL 10 ng/L (females) and 20 ng/L (males); abnormal elevation above the URL and delta >30%). Treating physicians were blinded to the hs-cTnI results. Using the hs-cTnI values, investigators retrospectively assigned likely diagnosis, disposition and likelihood of a 30-day major adverse cardiac event (MACE). Admission was recommended for significantly rising hs-cTnI elevations. The primary objective was to demonstrate an acceptable unexpected 30-day post-discharge MACE rate of <1%. cTnI elevation rates, diagnostic outcomes and ED disposition were also compared between pathways.ResultsFor the 935 patients, unexpected 30-day post-discharge MACE rates were 0/935 (0%, 95% CI 0% to 0.4%) with the conventional or novel pathway. For the high-sensitivity and conventional assays, respectively, abnormal elevation rates were 29% (95% CI 26% to 32%) and 19% (95% CI 17% to 22%), for MI were 9% (95% CI 8% to 11%) and 8% (95% CI 6% to 10%), and for hospital admission were 42% (95% CI 39% to 45%) and 43% (95% CI 40% to 47%).ConclusionThe novel pathway using the Access hsTnI assay has an acceptably low 30-day MACE rate.

scholarly journals Concordance, Variance, and Outliers in 4 Contemporary Cardiac Troponin Assays: Implications for Harmonization

2012 ◽  
Vol 58 (1) ◽  
pp. 274-283 ◽  
Author(s):  
Jacobus P J Ungerer ◽  
Louise Marquart ◽  
Peter K O'Rourke ◽  
Urs Wilgen ◽  
Carel J Pretorius
Keyword(s):  
Myocardial Infarction ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Troponin T ◽  
Analytical Imprecision ◽  
Universal Definition ◽  
Definition Of ◽  
Abbott Architect ◽  
Roche Cobas

Abstract BACKGROUND Data to standardize and harmonize the differences between cardiac troponin assays are needed to support their universal status in diagnosis of myocardial infarction. We characterized the variation between methods, the comparability of the 99th-percentile cutoff thresholds, and the occurrence of outliers in 4 cardiac troponin assays. METHODS Cardiac troponin was measured in duplicate in 2358 patient samples on 4 platforms: Abbott Architect i2000SR, Beckman Coulter Access2, Roche Cobas e601, and Siemens ADVIA Centaur XP. RESULTS The observed total variances between the 3 cardiac troponin I (cTnI) methods and between the cTnI and cardiac troponin T (cTnT) methods were larger than expected from the analytical imprecision (3.0%–3.7%). The between-method variations of 26% between cTnI assays and 127% between cTnI and cTnT assays were the dominant contributors to total variances. The misclassification of results according to the 99th percentile was 3%–4% between cTnI assays and 15%–17% between cTnI and cTnT. The Roche cTnT assay identified 49% more samples as positive than the Abbott cTnI. Outliers between methods were detected in 1 patient (0.06%) with Abbott, 8 (0.45%) with Beckman Coulter, 10 (0.56%) with Roche, and 3 (0.17%) with Siemens. CONCLUSIONS The universal definition of myocardial infarction should not depend on the choice of analyte or analyzer, and the between- and within-method differences described here need to be considered in the application of cardiac troponin in this respect. The variation between methods that cannot be explained by analytical imprecision and the discordant classification of results according to the respective 99th percentiles should be addressed.

scholarly journals Sensitive impedimetric detection of troponin I with metal–organic framework composite electrode

RSC Advances ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 2167-2174
Author(s):  
Arushi Gupta ◽  
Sandeep Kumar Sharma ◽  
Vivek Pachauri ◽  
Sven Ingebrandt ◽  
Suman Singh ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Composite Electrode ◽  
Troponin I ◽  
Limit Of Detection ◽  
Metal Organic Framework ◽  
Cardiac Troponin I ◽  
Sensitive Detection ◽  
Wide Concentration Range ◽  
Screen Printed Electrode ◽  
Metal Organic

A Cu-MOF/PANI modified screen-printed electrode based immunosensing technique is described for the sensitive detection of cardiac troponin I. The sensor provides detection over a wide concentration range with a limit of detection of 0.8 ng mL−1.

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