High-sensitivity Troponin Assays Research Articles

Knowledge of the high-sensitivity cardiac troponin assay among medical officers in Gampaha District, Sri Lanka: A cross sectional study

Knowledge of the high-sensitivity cardiac troponin assay among medical officers in Gampaha District, Sri Lanka: A cross sectional study

Evaluation of Age and Sex Differences in Contemporary versus High-Sensitivity Troponin I Measurement in Hospitalized Patients.

Background: With the transition from the contemporary (cTnI) to high-sensitivity troponin assay (hs-cTnI), concerns have arisen regarding the diagnostic differences between these two assays due to analytical distinctions. This study aims to evaluate the age and sex differences between these two assays, as well as the differences resulting from using two different 99th percentile values of the high-sensitivity troponin assay. Method: A retrospective observational study was conducted at an academic medical center, encompassing a total of 449 lithium heparin plasma samples included in the dataset. Both contemporary and high-sensitivity troponin were simultaneously measured using Siemens ADVIA Centaur analyzers. Two sets of sex-specific 99th percentile URLs from the Siemens study (cutoff-1) and Universal Sample Bank data (cutoff-2) were used for the data analysis. Results: The use of cutoff-1 or cutoff-2 had a negligible impact on troponin classification. Troponin elevation significantly increased in individuals > 50 years old for males and >40 years old for females, with both troponin assays. A receiver operating characteristic analysis did not find significant differences between the two assays. The Kaplan-Meier curves showed no differences in survival in cTnI according to the non-sex-specific 99th URL or hs-cTnI (cutoff-2) but showed a slight difference in survival in hs-cTnI (cutoff-1). Conclusions: Overall, there were no significant differences in age and sex in the diagnostic performance between the contemporary and high-sensitivity troponin assays. Selection criteria for the establishment of the 99th percentile URL should be standardized to avoid the misinterpretation of the troponin results.

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

BackgroundCompared to conventional cardiac troponin (cTn), the high-sensitivity cardiac troponin (hs-cTn) assay is associated with improved detection of myocardial infarction (MI). MethodsWe performed a descriptive retrospective analysis of resource utilization at Rush University Medical Center over the transition period (July 1, 2021) from a cTn to a hs-cTn assay. Inclusion criteria included emergency department (ED) encounters between January 1 to December 31, 2021, with chief complaints of “chest pain” or “dyspnea” with associated troponin orders. The primary endpoint was the percentage of ED discharges. Secondary endpoints included the number of cardiac studies ordered. Univariable comparisons of these endpoints were performed using Student's t-test for continuous variables and Chi-square tests for binary/categorical variables. ResultsA total of 5113 encounters were analyzed. Hs-cTn was associated with an overall increase in ED patient discharges with negative troponin tests (44.1% vs. 29.9%, P < 0.01). In terms of cardiac testing per encounter, hs-cTn was associated with significant increases in the number of troponin tests (1.9 vs. 1.6, P < 0.01), electrocardiograms (3.0 vs. 2.9, P = 0.01), and echocardiograms (0.5 vs. 0.4, P < 0.01). There was a significant decrease in the utilization of stress testing (0.21 vs. 0.26, P < 0.01). There was a significant increase in total coronary angiography use during the hs-cTn period compared to cTn (227/2471 (9.2%) vs. 195/2642 (7.4%), P = 0.02). ConclusionTransitioning from cTn to hs-cTn was associated with significantly increased ED discharges and an increase in troponin tests, ECG, echocardiograms, and coronary angiograms. There was a decrease in the number of stress tests.

Characterization of myocardial injury phenotype by thermal liquid biopsy.

With the advent and implementation of high-sensitivity cardiac troponin assays, differentiation of patients with distinct types of myocardial injuries, including acute thrombotic myocardial infarction (TMI), acute non-thrombotic myocardial injury (nTMi), and chronic coronary atherosclerotic disease (cCAD), is of pressing clinical importance. Thermal liquid biopsy (TLB) emerges as a valuable diagnostic tool, relying on identifying thermally induced conformational changes of biomolecules in blood plasma. While TLB has proven useful in detecting and monitoring several cancers and autoimmune diseases, its application in cardiovascular diseases remains unexplored. In this proof-of-concept study, we sought to determine and characterize TLB profiles in patients with TMI, nTMi, and cCAD at multiple acute-phase time points (T 0 h, T 2 h, T 4 h, T 24 h, T 48 h) as well as a follow-up time point (Tfu) when the patient was in a stable state. TLB profiles were collected for 115 patients (60 with TMI, 35 with nTMi, and 20 with cCAD) who underwent coronary angiography at the event presentation and had subsequent follow-up. Medical history, physical, electrocardiographic, histological, biochemical, and angiographic data were gathered through medical records, standardized patient interviews, and core laboratory measurements. Distinctive signatures were noted in the median TLB profiles across the three patient types. TLB profiles for TMI and nTMi patients exhibited gradual changes from T0 to Tfu, with significant differences during the acute and quiescent phases. During the quiescent phase, all three patient types demonstrated similar TLB signatures. An unsupervised clustering analysis revealed a unique TLB signature for the patients with TMI. TLB metrics generated from specific features of TLB profiles were tested for differences between patient groups. The first moment temperature (TFM) metric distinguished all three groups at time of presentation (T0). In addition, 13 other TLB-derived metrics were shown to have distinct distributions between patients with TMI and those with cCAD. Our findings demonstrated the use of TLB as a sensitive and data-rich technique to be explored in cardiovascular diseases, thus providing valuable insight into acute myocardial injury events.

High-sensitivity Troponin I Assay for Early Detection of Myocardial Injury in Carbon Monoxide Intoxication

Abstract Background: Carbon monoxide (CO) intoxication is the most common gas-related event resulting in emergency room (ER) visits, often leading to myocardial injuries measured through the assessment of troponin levels. Recent efforts have focused on developing high-sensitivity troponin assays for more accurate acute myocardial infarction diagnosis. However, studies using high-sensitivity troponin I (hs-TnI) assays to identify myocardial injury following CO intoxication are lacking. Aim: We compared the measurement of circulating troponin I levels using the hs-TnI assay and the contemporary troponin I (cTnI) assay. Materials and Methods: We prospectively analyzed 50 patients with CO intoxication who were admitted to the ER between September 2012 and October 2013. Clinical, demographic, electrocardiographic (ECG), echocardiographic, and laboratory data were compared. Circulating troponin I levels were measured using hs-TnI and cTnI assays upon arrival in the ER and 24, 48, and 72 h after admission. Results: Most patients with moderate or severe CO intoxication had elevated circulating troponin I levels, as detected using the hs-TnI assay. In addition, none of the results above or below the cutoff value for circulating troponin I changed from those found in the ER. In the cTnI assay, elevated circulating troponin I above the cutoff value in the ER was detected in 21 of 36 patients (58%). Participants with elevated troponin I levels, as measured by the hs-TnI assay, were more likely to experience various unfavorable clinical outcomes. Conclusion: The hs-TnI assay can detect elevated circulating troponin I levels earlier than the cTnI assay in patients with CO intoxication and myocardial injury.

Postoperative Myocardial Infarction after Non-Cardiac Surgery: An Update.

Every year, not less than 300 million non-cardiac surgery interventions are performed in the world. Perioperative mortality after non-cardiac surgery is estimated at 2% in patients over 45 years of age. Cardiovascular events account for half of these deaths, and most are due to perioperative myocardial infarction (MINS). The diagnosis of postoperative myocardial infarction, before the introduction of cardiac biomarkers, was based on symptoms and electrocardiographic changes and its incidence was largely underestimated. The incidence of MINS when a standard troponin assay is used ranges between 8 and 19% but increases to 20-30% with high-sensitivity troponin assays. Higher troponin values suggesting myocardial injury, both with or without a definite diagnosis of myocardial infarction, are associated with an increase in 30-day and 1-year mortality. Diagnostic and therapeutic strategies are reported.

Imprecision of high-sensitivity cardiac troponin assays at the female 99th-percentile

BackgroundAn analytical benchmark for high-sensitivity cardiac troponin (hs-cTn) assays is to achieve a coefficient of variation (CV) of ≤ 10.0 % at the 99th percentile upper reference limit (URL) used for the diagnosis of myocardial infarction. Few prospective multicenter studies have evaluated assay imprecision and none have determined precision at the female URL which is lower than the male URL for all cardiac troponin assays. MethodsHuman serum and plasma matrix samples were constructed to yield hs-cTn concentrations near the female URLs for the Abbott, Beckman, Roche, and Siemens hs-cTn assays. These materials were sent (on dry ice) to 35 Canadian hospital laboratories (n = 64 instruments evaluated) participating in a larger clinical trial, with instructions for storage, handling, and monthly testing over one year. The mean concentration, standard deviation, and CV for each instrument type and an overall pooled CV for each manufacturer were calculated. ResultsThe CVs for all individual instruments and overall were ≤ 10.0 % for two manufacturers (Abbott CVpooled = 6.3 % and Beckman CVpooled = 7.0 %). One of four Siemens Atellica instruments yielded a CV > 10.0 % (CVpooled = 7.7 %), whereas 15 of 41 Roche instruments yielded CVs > 10.0 % at the female URL of 9 ng/L used worldwide (6 cobas e411, 1 cobas e601, 4 cobas e602, and 4 cobas e801) (CVpooled = 11.7 %). Four Roche instruments also yielded CVs > 10.0 % near the female URL of 14 ng/L used in the United States (CVpooled = 8.5 %). ConclusionsThe number of instruments achieving a CV ≤ 10.0 % at the female 99th-percentile URL varies by manufacturer and by instrument. Monitoring assay precision at the female URL is necessary for some assays to ensure optimal use of this threshold in clinical practice.

Could Computed Tomography Coronary Angiography Replace Invasive Coronary Angiography as a First-Line Diagnostic Investigation in Suspected Acute Coronary Syndromes? A Decision-Analytic Model

The implementation of high-sensitivity cardiac troponin (hs-cTn) assays into clinical practice has resulted in the identification of a novel cohort of patients with modestly increased troponin concentrations. Subsequent increases in rates of coronary angiography have been observed, without significant increases in rates of coronary revascularisation. Computed tomography coronary angiography (CTCA) is a non-invasive investigation that offers the opportunity to decouple investigation from the impetus to revascularise, and may provide an alternative, more risk-appropriate initial investigative strategy for the cohort with low to moderate hs-cTn increases. This analysis seeks to define the threshold of pre-test probability of coronary revascularisation in patients with suspected acute coronary syndrome at which a strategy of initial CTCA is safe and a more cost-effective approach than standard invasive coronary angiography (ICA). A cost-benefit evaluation was conducted using a decision-analytic model. The primary outcome measure was the incremental cost-effectiveness ratio (ICER) of CTCA in comparison with ICA as an initial diagnostic investigation for patients with hs-cTnT levels between 5 and 100 ng/L. Secondary outcome measures of costs, patient outcomes, and quality-adjusted life years were analysed. Median base case ICER over 1,000 trials was $17,163 AUD but demonstrated large variability. Sensitivity analysis demonstrated that CTCA was cost-effective until the probability of requiring revascularisation was ∼60%, beyond which point CTCA was associated with higher costs and poorer outcomes than ICA. Computed tomography coronary angiography may be a cost-effective first-line investigation for patients with moderate hs-cTnT rises until/up to a 60% pre-test probability for receiving coronary revascularisation. To objectively assess the optimal circumstances of cost-effectiveness, prospective evaluation incorporating the estimated probability of revascularisation will be required.

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.

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. 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. 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 %). 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.

External validation of a rapid algorithm using high-sensitivity troponin assay results for evaluating patients with suspected acute myocardial infarction

ObjectiveWe sought to validate the clinical performance of a rapid assessment pathway incorporating the Siemens Atellica IM high sensitivity cardiac troponin I (hs-cTnI) assay in patients presenting to the emergency...

Four high sensitivity troponin assays and mortality in US adults with cardiovascular disease: The national health and nutrition examination survey, 1999–2004

ObjectiveHigh sensitivity cardiac troponin (hs-cTn) may be useful to monitor residual risk in secondary prevention. Our objective was to study the correlations and comparative associations with mortality of four hs-cTn assays in US adults with known cardiovascular disease (CVD). MethodsWe studied 1,211 adults with a history of CVD who participated in the National Health and Nutrition Examination Survey (NHANES) 1999–2004. Using stored samples, we measured hs-cTnT (Roche) and three hs-cTnI assays (Abbott, Siemens, and Ortho). Outcomes were all-cause and CVD mortality, with follow-up through December 31, 2019. ResultsMean age was 64 years, 48 % were female, and 80 % identified as non-Hispanic White. Pearson's correlation coefficients between hs-cTn assays ranged from 0.67 to 0.85. There were 848 deaths (365 from CVD). Among adults with a history of prior non-fatal CVD, each hs-cTn assay (log-transformed, per 1-SD) was independently associated with CVD death (HRs ranging from 1.55 to 2.16 per 1-SD, all p-values <0.05) and with all-cause death (HRs ranging from 1.31 to 1.62 per 1-SD, all p-values <0.05). Associations of hs-cTnT and all-cause and CVD death remained significant after adjusting for hs-cTnI (and vice versa). Associations between hs-cTnI and CVD death remained significant after mutually adjusting for other individual hs-cTnI assays: e.g., HR 2.21 (95 % CI 1.60, 3.05) for Ortho (hs-cTnI) after adjustment for Siemens (hs-cTnI) and HR 1.81 (95 % CI 1.35, 2.43) for Ortho (hs-cTnI) after adjustment for Abbott (hs-cTnI). ConclusionIn US adults with a history of CVD, we found modest correlations between 4 hs-cTn assays. All assays were associated with all-cause and CVD mortality. The hs-cTnT assay was associated with mortality independent of the hs-cTnI assays. Hs-cTnI assays also appeared to be independent of each other. Thus, hs-cTn assays may provide distinct information for residual risk in secondary prevention adults.

Current Evidence for the Use of High-Sensitivity Troponin Assays in the Emergency Department

Current Evidence for the Use of High-Sensitivity Troponin Assays in the Emergency Department

Knowledge of the high-sensitivity cardiac troponin assay among medical officers in Gampaha District, Sri Lanka

Introduction: The high-sensitivity cardiac troponin (hs-cTn) assay is a crucial diagnostic test that is obligatory in the triage of patients presenting with chest pain. It is essential for medical officers to have adequate knowledge regarding the procedures for testing and the interpretation of test outcomes to deliver optimal healthcare for patients. It has been observed that medical officers are lacking in awareness regarding this testing method, resulting in a greater likelihood of errors in testing and interpretation. This study aims to evaluate the level of understanding among medical officers regarding the hs-cTn assay in relation to the most recent European Society of Cardiology guideline released in 2020.Methodology: We conducted a cross-sectional study at two government hospitals in Gampaha District in June 2022. A self-administered e-questionnaire was used to assess knowledge regarding hs-cTn. Knowledge was measured by calculating a cumulative score for the answers to a questionnaire and categorised into good or poor knowledge. A score less than 60% was categorized as poor and vice versa. Descriptive statistics were used to summarize the data.Results: Of the 227 medical officers, only 14.5% (n=33) had good knowledge of the analytical component while 41.9% (n=95) had good knowledge on the clinical component. A score ≥60% on the analytical component knowledge was significantly associated with designation being a senior registrar or consultant (p&lt;0.001), postgraduate enrolment (p&lt;0.001), participation in continuous professional development programmes (p&lt;0.001), and employment in a teaching hospital (p=0.025), but not with age (p=0.066) or private practice (p=0.118). Clinical component knowledge score ≥60% was significantly associated with age between 25 and 35 years (p=0.006), designation being a consultant (p&lt;0.001), postgraduate enrolment (p&lt;0.001), participation in continuous professional development programs (p&lt;0.001), and employment in a teaching hospital(p=0.001) but not with doing private practice (p=0.170).Conclusions: In Sri Lanka, medical officers’ general knowledge on the hs-cTn assay seems lacking. There is a need for continuous training to improve knowledge on hs-cTn testing among medical officers.

Optimizing the Clinical Use of High-Sensitivity Troponin Assays: A Review.

Ischemic heart diseases (IHDs) remain a global health concern. Many IHD cases go undiagnosed due to challenges in the initial diagnostic process, particularly in cases of acute myocardial infarction (AMI). High-sensitivity cardiac troponin (hs-cTn) assays have revolutionized myocardial injury assessment, but variations in diagnostic cut-off values and population differences have raised challenges. This review addresses essential laboratory and clinical considerations for hs-cTn assays. Laboratory guidelines discuss the importance of establishing standardized 99th-percentile upper reference limits (URLs) considering factors such as age, sex, health status, and analytical precision. The reference population should exclude individuals with comorbidities like diabetes and renal disease, and rigorous selection is crucial. Some clinical guidelines emphasize the significance of sex-specific URL limits while others do not. They highlight the use of serial troponin assays for AMI diagnosis. In addition, timely reporting of accurate hs-cTn results is essential for effective clinical use. This review aims to provide a clearer understanding among laboratory professionals and clinicians on how to optimize the use of hs-cTn assays in clinical settings in order to ensure accurate AMI diagnosis and thus improve patient care and outcomes.

Emergency Department Cardiac Risk Stratification With High-Sensitivity vs Conventional Troponin HEART Pathway

Patients presenting to the emergency department with chest pain are routinely risk stratified for major adverse cardiac events using the HEART (History, Electrocardiogram, Age, Risk factors, and Troponin) score pathway, which incorporates clinical features, risk factors, electrocardiography findings, and initial serum troponin testing. A new HEART pathway incorporating high-sensitivity troponin level may improve risk stratification among patients with possible acute myocardial infarction (AMI). To compare health outcomes and resource use among emergency department patients undergoing cardiac risk stratification with a HEART pathway using conventional vs high-sensitivity serum troponin. This multicenter pre-post cohort study was conducted between January 1 and September 6, 2021, at 16 Kaiser Permanente Southern California hospitals during uptake of a high-sensitivity serum troponin assay and included 17 384 adult patients who presented to an emergency department with chest pain and were risk stratified with a HEART pathway based on conventional troponin or high-sensitivity troponin. A HEART pathway incorporating either conventional or high-sensitivity serum troponin was used to stratify study groups for risk of major adverse cardiac events within 30 days. The primary outcome was detection of AMI in the emergency department and within 30 days. Of the 17 384 patients (median age, 58 years [IQR, 45-69 years]; 9767 women [56.2%]), 12 440 (71.6%) were risk stratified with a HEART pathway based on conventional troponin, and 4944 (28.4%) were risk stratified with a HEART pathway based on high-sensitivity troponin. Detection of AMI within 30 days was higher for the high-sensitivity troponin group than the conventional troponin group (288 [5.8%] vs 545 [4.4%]; P < .001), while the 30-day all-cause mortality rate was unchanged (16 [0.3%] vs 50 [0.4%]; P = .50). In the emergency department, 228 of 4944 patients (4.6%) in the high-sensitivity troponin group received a diagnosis of AMI compared with 251 of 12 440 patients (2.0%) in the conventional troponin group (P < .001). Among those who did not receive a diagnosis of AMI in the emergency department, an additional 60 patients (1.2%) in the high-sensitivity troponin group and 294 (2.4%) in the conventional troponin group (P < .001) received a diagnosis within 30 days. Patients in the high-sensitivity troponin group had lower rates of health care use compared with the conventional troponin group, including admission (605 [12.2%] vs 1862 [15.0%]; P < .001), stress testing within 7 days (506 [10.2%] vs 1591 [12.8%]; P < .001), and coronary revascularization within 30 days (51 [1.0%] vs 244 [2.0%]; P < .001). This multicenter pre-post cohort study suggests that a new HEART pathway incorporating high-sensitivity troponin may improve detection of AMI and decrease resource use among emergency department patients with chest pain.

Prevalence and outcome of clinical misdiagnosis of non-ST-elevation myocardial infarction

Abstract Background The prevalence of clinical misdiagnosis of non-ST-elevation myocardial infarction (NSTEMI) and its impact on patient outcomes is largely unknown. Methods We prospectively enrolled adult patients presenting with suspected acute coronary syndromes at 12 sites in five European countries. All patients provided written informed consent and were managed as per local clinical care using conventional, sensitive or high-sensitivity cardiac troponin (hs-cTn) assays. Study blood samples were taken at presentation and serially thereafter for measurements of hs-cTn concentrations. Final diagnoses were adjudicated by two independent cardiologists according to current guidelines and the 4th universal definition of myocardial infarction using all information including serial hs-cTnT measurements and imaging. The primary diagnostic endpoint was the prevalence of clinical NSTEMI misdiagnosis. Co-primary prognostic endpoints were 30 day and two year all-cause and cardiovascular (CV) death. Results In 7,678 patients (median age 61 [IQR 48-73], 34% women), the prevalence of adjudicated and clinical NSTEMI was 17.8% and 12.3%, respectively (P&amp;lt;0.001). Among 1,363 patients with an adjudicated NSTEMI (77% type 1 MI, 23% type 2 MI), 470/1,363 (34%) had a clinical NSTEMI misdiagnosis. These patients were older, more often female, had lower median cTn concentrations, and were more likely managed at centers using non-hs-cTn assays at time of enrolment. Compared to patients with an adjudicated and clinical NSTEMI diagnosis, missed patients were less likely to undergo coronary angiography or revascularization and less often discharged on evidence-based treatment (dual antiplatelet therapy 24% vs 79%, statin 64% vs 92%, betablocker 68% vs 81%, all P&amp;lt;0.001). Finally, patients with a clinical NSTEMI misdiagnosis were at much higher risk of premature all-cause (HR 1.51, 95% CI 1.18-1.94, P&amp;lt;0.001) and CV (HR 1.93, 95%CI 1.42-2.63, P&amp;lt;0.001) death. Conclusion One out of three adjudicated NSTEMI patients was misdiagnosed in routine clinical care. Clinical NSTEMI misdiagnosis was associated with lower use of guideline-recommended therapies and a substantial increase in premature death.Alluvial plotAll-cause death at 2-years

Simultaneous, free-breathing, non-contrast 3D whole-heart coronary magnetic resonance angiography and vulnerable plaque imaging in patients with suspected acute coronary syndrome

Abstract Background Coronary artery high-risk plaque identified on cardiovascular magnetic resonance (CMR) is associated with future coronary events, independent of coronary artery luminal stenosis. We have recently developed a 3-dimensional whole-heart free-breathing non-contrast CMR sequence that allows for simultaneous high-resolution visualisation of the coronary arteries and vulnerable plaque on co-registered bright and black blood images (iT2prep-BOOST) with 100% respiratory scan efficiency. Objectives To validate iT2prep-BOOST in patients with non-ST-segment elevation myocardial infarction (NSTEMI) against the reference standard imaging modalities of invasive X-ray coronary angiography and intravascular imaging [optical coherence tomography (OCT)/intravascular ultrasound (IVUS)]. Methods 41 consecutive patients with suspected NSTEMI, based upon clinical history, electrocardiographic changes and positive high-sensitivity troponin assays, were recruited into the study. Invasive coronary angiography ± intravascular imaging was used to classify coronary segments into the following categories: normal, non-culprit and culprit segments; stenosed segments as well as segments with vulnerable plaque features (lipid, calcium, fibroatheroma, thin cap fibroatheroma (TCFA), plaque rupture and thrombus). The highest plaque/myocardial signal intensity ratio (PMR) in each coronary segment was analysed on iT2prep-BOOST. Results The mean iT2prep-BOOST acquisition time was 10.8 ± 1.3 minutes. The mean ± standard error of mean (SEM) PMR of culprit segments was significantly higher than non-culprit segments, which was significantly higher than normal segments (1.01 ± 0.05 vs. 0.67 ± 0.01 vs. 0.35 ± 0.01, P&amp;lt;0.001). Coronary segments with lipid, calcium and fibroatheroma had a significantly higher PMR compared to normal coronary segments (P&amp;lt;0.001) but lower than segments with TCFA, plaque rupture and thrombus (P&amp;lt;0.001). There was a progressive increase in PMR with increasing degree of coronary stenosis (P&amp;lt;0.001). Patients with type 2 diabetes, hypertension, hyperlipidaemia and family history of coronary artery disease had a significantly higher PMR on iT2prep-BOOST (P&amp;lt;0.001, P=0.02, P=0.04 and P=0.02 respectively). Finally, PMR was positively correlated with HbA1c, total cholesterol, non-HDL cholesterol, LDL cholesterol and triglyceride levels (P&amp;lt;0.001, P=0.02, P=0.02, P=0.05 and P=0.05 respectively). Conclusions In summary, the proposed iT2prep-BOOST framework has the potential to simultaneously acquire coronary artery angiography and to differentiate normal segments from non-culprit and culprit plaque segments. Furthermore, PMR is associated with both biochemical and patient related risk factors for coronary artery disease (CAD). The long-term prognostic value of PMR needs to be investigated in a longitudinal multi-centre study of patients with suspected CAD.Figure 1Figures 2 and 3

Aiming toWards Evidence baSed inTerpretation of Cardiac biOmarkers in patients pResenting with chest pain using Point of Care Testing (WESTCOR-POC): study design

Objectives Patients presenting with symptoms suggestive of acute coronary syndrome (ACS) contribute to a high workload and overcrowding in the Emergency Department (ED). Accelerated diagnostic protocols for non-ST-elevation myocardial infarction have proved challenging to implement. One obstacle is the turnaround time for analyzing high-sensitivity cardiac troponin (hs-cTn). In the WESTCOR-POC study (Clinical Trials number NCT05354804) we aim to evaluate safety and efficiency of a 0/1 h hs-cTn algorithm utilizing a hs-cTnI point of care (POC) instrument in comparison to central laboratory hs-cTnT measurements. Design This is a prospective single-center randomized clinical trial aiming to include 1500 patients admitted to the ED with symptoms suggestive of ACS. Patients will receive standard investigations following the European Society of Cardiology 0/1h protocols for centralized hs-cTnT measurements or the intervention using a 0/1h POC hs-cTnI algorithm. Primary end-points are 1) Safety; death, myocardial infarction or acute revascularization within 30 days 2) Efficiency; length of stay in the ED, 3) Cost- effectiveness; total episode cost, 4) Patient satisfaction, 5) Patient symptom burden and 6) Patients quality of life. Secondary outcomes are 12-months death, myocardial infarction or acute revascularization, percentage discharged after 3 and 6 h, total length of hospital stay and all costs related to hospital contact within 12 months. Conclusion Results from this study may facilitate implementation of POC hs-cTn testing assays and accelerated diagnostic protocols in EDs, and may serve as a valuable resource for guiding future investigations for the use of POC high sensitivity troponin assays in outpatient clinics and prehospital settings.

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

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. 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). 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.

Sex-Specific Cardiac Troponin Thresholds in Transgender Patients With Suspected Acute Coronary Syndrome

This cohort study compares the use and outcomes of high-sensitivity cardiac troponin assay vs conventional troponin assay in transgender adults.