Diagnostic Performance of Novel Troponin Algorithms for the Rule-Out of Non-ST-Elevation Acute Coronary Syndrome

Abstract

Background The European Society of Cardiology (ESC) rule-out algorithms use cutoffs optimized for exclusion of non-ST elevation myocardial infarction (NSTEMI). We investigated these and several novel algorithms for the rule-out of non-ST elevation acute coronary syndrome (NSTE-ACS) including less urgent coronary ischemia. Method A total of 1504 unselected patients with suspected NSTE-ACS were included and divided into a derivation cohort (n = 988) and validation cohort (n = 516). The primary endpoint was the diagnostic performance to rule-out NSTEMI and unstable angina pectoris during index hospitalization. The secondary endpoint was combined MI, all-cause mortality (within 30 days) and urgent (24 h) revascularization. The ESC algorithms for high-sensitivity cardiac troponin T (hs-cTnT) and I (hs-cTnI) were compared to different novel low-baseline (limit of detection), low-delta (based on the assay analytical and biological variation), and 0–1-h and 0–3-h algorithms. Results The prevalence of NSTE-ACS was 24.8%, 60.0% had noncardiac chest pain, and 15.2% other diseases. The 0–1/0–3-h algorithms had superior clinical sensitivity for the primary endpoint compared to the ESC algorithm (validation cohort); hs-cTnT: 95% vs 63%, and hs-cTnI: 87% vs 64%, respectively. Regarding the secondary endpoint, the algorithms had similar clinical sensitivity (100% vs 94%–96%) but lower clinical specificity (41%–19%) compared to the ESC algorithms (77%–74%). The rule-out rates decreased by a factor of 2–4. Conclusion Low concentration/low-delta troponin algorithms improve the clinical sensitivity for a combined endpoint of NSTEMI and unstable angina pectoris, with the cost of a substantial reduction in total rule-out rate. There was no clear benefit compared to ESC for diagnosing high-risk events.

Cardiac Biomarkers in 2022 – a Vital Tool for Emergency Care

“…67 In another study which compared new algorithms with the standard ESC-recommended algorithm used for ruling out NSTEMI based on cTn measurements, investigators found that a 0-1 h/0-3 h algorithm based on low baseline level and low variation had superior clinical sensitivity than the ESC algorithm: 95% vs. 65% for hs-cTnT and 87% vs. 64% for hs-cTnI. 68 The RAPID-TnT trial aimed to investigate the economic impact of the accelerated protocol for 0/1 h testing of hs-cTnT and found that despite an initial superior efficiency of the accelerated protocol, it led to no significant reduction of resource utilization compared to the standard 0/3 h protocol. Despite reducing the length of stay in the ED by 0.62 h per patient, the costs recorded were higher in the 0/1 h protocol arm by 472.49 USD per patient.…”

High-Sensitivity Cardiac Troponin T and the Diagnosis of Cardiovascular Disease in the Emergency Room: The Importance of Combining Cardiovascular Biomarkers with Clinical Data

“…Over time, the new high-sensitivity assays have improved diagnostic accuracy, being capable of detecting levels of cTn from 10 to 100 times lower than traditional tests. In this way, the high sensitivity cTn assays sped up the MI exclusion diagnostic process, thanks also to the introduction of several algorithms in the emergency room (ER) focused on its values at time 0 and after 1 or 2 h [2,[6][7][8][9][10]. Furthermore, the introduction of some clinical scores has improved the interpretation of the cTn values, even if not making them completely free from misunderstandings [11][12][13][14].…”

Predictors of long-term symptom burden and quality of life in patients hospitalised with chest pain: a prospective observational study

“…UAP patients may differ from NSTEMI patients and typically have ischaemic cardiac disease being less available for revascularisation 9 10. They are typically ‘ruled-out’ by the ESC algorithms for non-ST segment elevation acute coronary syndrome (NSTE-ACS) 11 12. There is an ongoing debate on how this condition should be defined and what is the optimal treatment options after the implementation of high sensitivity troponin assays 13.…”