Diagnostic accuracy of a high-sensitivity troponin I assay and external validation of 0/3 h rule out strategies

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

OBJECTIVE

We 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 department (ED) with suspected acute myocardial infarction (AMI).

METHODS

This was a multicentre prospective observational study of adult ED patients presenting to five Australian hospitals between November 2020 and September 2021. Participants included those with symptoms of suspected AMI (without ST-segment elevation MI on presentation ECG). The Siemen's Atellica IM hs-cTnI laboratory-based assay was used to measure troponin concentrations at admission and after 2-3 hours and cardiologists adjudicated final diagnoses. The HighSTEACS diagnostic algorithm was evaluated, incorporating hs-cTnI concentrations at presentation and absolute changes within the first 2 to 3 hours. The primary outcome was index AMI, including type 1 or 2 non-ST segment elevation MI (NSTEMI) or ST-elevation MI (STEMI) following presentation. 30-day major adverse cardiac outcomes (including AMI, urgent revascularisation or cardiac death) were also reported. The trial was registered with the Australian and New Zealand Clinical Trials Registry.

RESULTS

1994 patients were included. The average age was 56.2 years (SD=15.6), and 44.9% were women. 118 (5.9%) patients had confirmed index AMI. The 2-hour algorithm defined 61.3% of patients as low risk. Sensitivity was 99.1% (94.0%-99.9%) and negative predictive value was 99.9% (99.3%-100%). 24.4% of patients were deemed intermediate risk. When applying the parameters for high risk, 252 (14.3%) were identified, with a specificity of 91.5% (88.7%-93.6%) and a PPV of 42.0% (35.6-48.7%).

CONCLUSIONS

A 2-hour algorithm based on the HighSTEACS strategy using the Siemens Atellica IM hs-cTnI laboratory-based assay enables safe and efficient risk assessment of emergency patients with suspected AMI.

TRIAL REGISTRATION NUMBER

ACTRN12621000053820.

Outcomes of European Society of Cardiology 0/1-h algorithm with high-sensitivity cardiac troponin T among patients with coronary artery disease

OBJECTIVE

The European Society of Cardiology (ESC) 0/1-h Algorithm with high-sensitivity cardiac troponin T (hs-cTnT) has shown promising results in risk stratification and management of patients with coronary artery disease (CAD). However, its outcomes and clinical implications in the context of developing countries remain understudied.

METHODS

This cohort study aimed to evaluate the outcomes and clinical significance of the ESC 0/1-h Algorithm in a developing country setting. A total of 3534 patients with CAD were enrolled, with 1125 in the Rule-Out group and 2409 in the Rule-In group. Baseline characteristics, performance metrics, primary and secondary outcomes, and predictors of Rule-In and Rule-Out groups were assessed.

RESULTS

The study enrolled 3534 patients with CAD, with 1125 in the Rule-Out group and 2409 in the Rule-In group. The 0/1-h Algorithm with hs-cTnT demonstrated improved performance compared to Troponin T at Presentation. It exhibited higher sensitivity, specificity, negative predictive value, positive predictive value, and area under the curve (AUC) for risk stratification in patients with CAD. Significant differences were observed in baseline characteristics between the Rule-Out and Rule-In groups, including age, gender, and comorbidities. The Rule-In group had a higher incidence of adverse cardiac events and underwent more invasive procedures compared to the Rule-Out group. Age, gender, hypertension, diabetes, and smoking were identified as significant predictors of Rule-In and Rule-Out. These findings highlight the clinical significance of implementing the 0/1-h Algorithm in the management of patients with CAD in a developing country setting.

CONCLUSION

The algorithm's performance, along with its ability to identify high-risk patients and predict outcomes, highlights its potential to enhance patient care and outcomes in resource-limited settings.

Cardiac Biomarkers in 2022 – a Vital Tool for Emergency Care

The role of cardiac biomarkers in diagnosing acute myocardial infarction is undoubted. In the 2020 guidelines of the European Society of Cardiology, the measurement of cardiac peptides to gain prognostic information has a class IIa indication in all patients with ACS. In emergency care, ruling out a non-ST elevation myocardial infarction requires documentation of normal levels of cardiac biomarkers, which remain stable or have very small variations within several hours. This review aims to summarize the current knowledge and recent progresses in the field of cardiac biomarker discovery, from their routine use in emergency rooms to their prognostic roles in modern risk assessment tools. Integrated approaches combining cardiac troponin with other biomarkers of ventricular dysfunction or inflammation, or with modern cardiac imaging in emergency care are also presented, as well as the role of modern algorithms for serial troponin measurement in the modern management of emergency departments.