Diagnostic accuracy of the Troponin-only Manchester Acute Coronary Syndromes (T-MACS) decision aid with a point-of-care cardiac troponin assay

Diagnostic and Cost Efficiency of the 0-h/1-h Rule-out and Rule-in Algorithm for Patients With Chest Pain in the Emergency Department

BACKGROUND

This study investigated the economic impact of the European Society of Cardiology (ESC) clinical practice guideline recommendation of using the 0-h/1-h rule-out and rule-in algorithm with high-sensitivity cardiac troponin assays (0/1-h algorithm) to triage patients presenting with chest pain.Methods and Results: This post hoc cost-effectiveness evaluation (DROP-ACS; UMIN000030668) used deidentified electronic medical records from health insurance claims from 2 diagnostic centers in Japan. A cost-effectiveness analysis was conducted with 472 patients with care provided following the 0/1-h algorithm (Hospital A) and 427 patients following point-of-care testing (Hospital B). The clinical outcome of interest was all-cause mortality or subsequent myocardial infarction within 30 days of the index presentation. The sensitivity and specificity for the clinical outcome were 100% (95% confidence interval [CI] 91.1-100%) and 95.0% (95% CI 94.3-95.0%), respectively, in Hospital A and 92.9% (95% CI 69.6-98.7%) and 89.8% (95% CI 89.0-90.0%), respectively, in Hospital B. If the diagnostic accuracy of the 0/1-h algorithm was implemented in Hospital B, it is expected that the number of urgent (<24-h) coronary angiograms would decrease by 50%. Incorporating this assumption, implementing the 0/1-h algorithm could potentially reduce medical costs by JPY4,033,874 (95% CI JPY3,440,346-4,627,402) in Hospital B (JPY9,447 per patient; 95% CI JPY 8,057-10,837 per patient).

CONCLUSIONS

The ESC 0/1-h algorithm was efficient for risk stratification and for reducing medical costs.

Clinical performance of 0/1 h cardiac troponin algorithm for diagnosing non-ST-segment elevation myocardial infarction 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.

Establishment of a nomogram model for acute chest pain triage in the chest pain center

Background

Acute myocardial infarction (AMI) is the leading life-threatening disease in the emergency department (ED), so rapid chest pain triage is important. This study aimed to establish a clinical prediction model for the risk stratification of acute chest pain patients based on the Point-of-care (POC) cardiac troponin (cTn) level and other clinical variables.

Methods

We conducted a post-hoc analysis of the database from 6,019 consecutive patients (excluding prehospital-diagnosed non-cardiac chest pain patients) attending a local chest pain center (CPC) in China between October 2016 and January 2019. The plasma concentration of cardiac troponin I (cTnI) was measured using a POC cTnI (Cardio Triage, Alere) assay. All the eligible patients were randomly divided into training and validation cohorts by a 7:3 ratio. We performed multivariable logistic regression to select variables and build a nomogram based on the significant predictive factors. We evaluated the model's generalization ability of diagnostic accuracy in the validation cohort.

Results

We analyzed data from 5,397 patients that were included in this research. The median turnaround time (TAT) of POC cTnI was 16 min. The model was constructed with 6 variables: ECG ischemia, POC cTnI level, hypotension, chest pain symptom, Killip class, and sex. The area under the ROC curve (AUC) in the training and validation cohorts was 0.924 and 0.894, respectively. The diagnostic performance was superior to the GRACE score (AUC: 0.737).

Conclusion

A practical predictive model was created and could be used for rapid and effective triage of acute chest pain patients in the CPC.

Major adverse cardiac event rates in moderate-risk patients: Does prior coronary disease matter?

BACKGROUND

Despite negative troponins and nonischemic electrocardiograms (ECGs), patients at moderate risk for acute coronary syndrome (ACS) are frequently admitted. The objective of this study was to describe the major adverse cardiac event (MACE) rate in moderate-risk patients and how it differs based on history of coronary artery disease (CAD).

METHODS

A secondary analysis of the HEART Pathway implementation study was conducted. This prospective interrupted time-series study accrued adults with possible ACS from three sites (November 2013-January 2016). This analysis excluded low-risk patients determined by emergency providers' HEART Pathway assessments. Non-low-risk patients were further classified as high risk, based on elevated troponin measures or ischemic ECG findings or as moderate risk, based on HEAR score ≥ 4, negative troponin measures, and a nonischemic ECG. Moderate-risk patients were then stratified by the presence or absence of prior CAD (MI, revascularization, or ≥70% coronary stenosis). MACE (death, myocardial infarction, or revascularization) at 30 days was determined from health records, insurance claims, and death index data. MACE rates were compared among groups using a chi-square test and likelihood ratios (LRs) were calculated.

RESULTS

Among 4,550 patients with HEART Pathway assessments, 24.8% (1,130/4,550) were high risk and 37.7% (1715/4550) were moderate risk. MACE at 30 days occurred in 3.1% (53/1,715; 95% confidence interval [CI] = 2.3% to 4.0%) of moderate-risk patients. Among moderate-risk patients, MACE occurred in 7.1% (36/508, 95% CI = 5.1% to 9.8%) of patients with known CAD versus 1.4% (17/1,207, 95% CI = 0.9% to 2.3%) in patients without known prior CAD (p < 0.0001). The negative LR for 30-day MACE among moderate-risk patients without prior CAD was 0.08 (95% CI = 0.05 to 0.12).

CONCLUSION

MACE rates at 30 days were low among moderate-risk patients but were significantly higher among those with prior CAD.

The association between cardiac risk factors and the probability of acute myocardial infarction in the emergency department: analysis from a multicentre prospective observational study in the high sensitivity troponin era

BACKGROUND AND OBJECTIVE

Hypertension, hyperlipidaemia, diabetes mellitus, smoking and family history are established risk factors for coronary artery disease. This study sought to determine the diagnostic value these factors have in patients presenting to an emergency department (ED) with suspected acute myocardial infarction (AMI).

DESIGN, SETTINGS AND ANALYSIS

This secondary analysis of a prospective diagnostic test accuracy study took place across 14 hospitals in England. A total of 1273 patients, presenting with suspected cardiac chest pain, were included for analysis - 179 (14.1%) had an adjudicated diagnosis of AMI.

OUTCOME MEASURE AND ANALYSIS

AMI diagnosis was adjudicated with serial troponin testing conducted on arrival and 3-12 hours later. The presence of any risk factors was documented at the time of initial presentation.

RESULTS

The post-test probability of AMI in the absence of risk factors (9.7%) shifts to only 23.5% when 4-5 factors are present. Associations of risk factors with AMI diagnosis were found as follows; hypertension [odds ratio (OR) 1.47, confidence interval (CI) 1.07-2.02], hyperlipidaemia (OR 1.57, CI 1.14-2.16), diabetes mellitus (OR 1.51, CI 1.04-2.20), smoking (OR 1.51, CI 1.05-2.17) and family history (OR 0.98, CI 0.71-1.37). The area under the receiver operating characteristic curve was 0.58.

CONCLUSION

Traditional cardiac risk factors have limited association with AMI in the ED, but an increasing risk factor burden is associated with increasing prevalence of AMI. These findings suggest that future work to refine existing decision aids used in this patient group may be of value.

Implementation of High-Sensitivity and Point-of-Care Cardiac Troponin Assays into Practice: Some Different Thoughts

Background

The primary role of the International Federation of Clinical Chemistry (IFCC) Committee on Clinical Application of Cardiac Bio-Markers (C-CB) is to provide educational materials about cardiac biomarker use, emphasizing high-sensitivity cardiac troponin assays.

Content

This mini-review, regarding high-sensitivity cardiac and point-of-care troponin assays, addresses 1) new IFCC C-CB/AACC Academy laboratory practice recommendations; 2) new and updated concepts from the Fourth Universal Definition of Myocardial Infarction; 3) the role of point-of-care assays in practice and research; 4) regulatory challenges concerning point-of-care assays; e) testing in the COVID-19 world.

Summary

Implementation of high-sensitivity cardiac troponin assays makes a difference now and into the future in clinical practice and research. Providing point-of-care high-sensitivity cardiac troponin assays and optimizing studies to allow clearance of these assays by regulatory agencies, in a timely fashion, may provide improved patient management and outcomes.

Cardiac biomarker measurement by point of care testing - Development, rationale, current state and future developments

Cardiac biomarker measurements are integral to the diagnosis and management of patients presenting with breathlessness and chest pain. Measurement of B type natriuretic peptide either directly or of the N-terminal portion of the prohormone although possible by point of care testing (POCT) has largely become a laboratory test. Measurement of the cardiac troponins cardiac troponin T (cTnT) and cardiac troponin I (cTnI) can easily and accurately be performed by POCT. The situation has been complicated by the development of high sensitivity assays for cTnT and cTnI and the subsequent development of rapid rule out algorithms allowing patient categorisation and discharge on admission and 1 to 2 h following admission. This article reviews the development of POCT for cardiac biomarkers, the evidence base comparing POCT with central laboratory testing, its strengths and limitations, and how POCT fits into the world of high sensitivity troponin assays. It also discusses what evidence there is that POCT can form part of rapid decision-making strategies and how this applies in an era of algorithms based on and is derived from measurement of high sensitivity troponin in the central laboratory.