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Novel Criteria for the Observe-Zone of the ESC 0/1h-hs-cTnT Algorithm
Pedro Lopez-Ayala1,2, Thomas Nestelberger1,2,3, Jasper Boeddinghaus1,2
1Cardiovascular Research Institute Basel and Department of Cardiology (P.L.-A., T.N., J.B., L.K., P.D.R., I.S., J.G., S.M., J.W., E.M., R.T., C.M.), University Hospital Basel, University of Basel, Switzerland.
Insights
New criteria combining 3-hour high-sensitivity cardiac troponin T levels and 0-3 hour change can safely rule out non-ST-elevation myocardial infarction (NSTEMI) in observation zones. This improves diagnostic efficiency for acute chest discomfort patients.
Area of Science:
- Cardiology
- Emergency Medicine
- Diagnostic Biomarkers
Background:
- European Society of Cardiology (ESC) guidelines recommend 3-hour cardiac troponin testing for non-ST-elevation myocardial infarction (NSTEMI) in observe-zone patients.
- No specific cutoff for further triage within the ESC 0/1h-algorithm's observe-zone is established.
- A proposed 0/3h high-sensitivity cardiac troponin T (hs-cTnT) change cutoff of 7 ng/L requires external validation.
Purpose of the Study:
- To externally validate the proposed 0/3h hs-cTnT change cutoff for NSTEMI triage.
- To derive and validate novel 0/3h criteria for the ESC 0/1h-hs-cTnT-algorithm's observe-zone.
- To improve diagnostic accuracy and efficiency in managing patients with acute chest discomfort.
Main Methods:
- Prospective enrollment of patients with acute chest discomfort in an international multicenter study.
- Serial hs-cTnT measurements at presentation, 1 hour, and 3 hours.
- Central adjudication of final diagnoses using the fourth universal definition of myocardial infarction.
Main Results:
- The proposed 0/3h hs-cTnT change <7 ng/L showed low sensitivity (33.3%) for ruling out NSTEMI.
- Novel derived criteria (3h hs-cTnT <15 ng/L and 0/3h absolute change <4 ng/L) ruled out NSTEMI with 99.2% sensitivity.
- These novel criteria reduced observe-zone patients by 36% and type 1 myocardial infarctions by 50%, confirmed internally and externally.
Conclusions:
- A combination of 3h hs-cTnT (<15 ng/L) and 0/3h absolute change (<4 ng/L) safely rules out NSTEMI in the ESC 0/1h-algorithm observe-zone.
- These criteria enhance diagnostic efficiency and reduce unnecessary investigations for NSTEMI.
- ClinicalTrials.gov Identifier: NCT00470587.
Background:
The non-ST-segment-elevation myocardial infarction (NSTEMI) guidelines of the European Society of Cardiology (ESC) recommend a 3h cardiac troponin determination in patients triaged to the observe-zone of the ESC 0/1h-algorithm; however, no specific cutoff for further triage is endorsed. Recently, a specific cutoff for 0/3h high-sensitivity cardiac troponin T (hs-cTnT) change (7 ng/L) was proposed, warranting external validation.
Methods:
Patients presenting with acute chest discomfort to the emergency department were prospectively enrolled into an international multicenter diagnostic study. Final diagnoses were centrally adjudicated by 2 independent cardiologists applying the fourth universal definition of myocardial infarction, on the basis of complete cardiac workup, cardiac imaging, and serial hs-cTnT. Hs-cTnT concentrations were measured at presentation, after 1 hour, and after 3 hours. The objective was to externally validate the proposed cutoff, and if necessary, derive and internally as well as externally validate novel 0/3h-criteria for the observe-zone of the ESC 0/1h-hs-cTnT-algorithm in an independent multicenter cohort.
Results:
Among 2076 eligible patients, application of the ESC 0/1h-hs-cTnT-algorithm triaged 1512 patients (72.8%) to either rule out or rule in NSTEMI, leaving 564 patients (27.2%) in the observe-zone (adjudicated NSTEMI prevalence, 120/564 patients, 21.3%). The suggested 0/3h-hs-cTnT-change of <7 ng/L triaged 517 patients (91.7%) toward rule-out, resulting in a sensitivity of 33.3% (95% CI, 25.5-42.2), missing 80 patients with NSTEMI, and ≥7 ng/L triaged 47 patients toward rule-in (8.3%), resulting in a specificity of 98.4% (95% CI, 96.8-99.2). Novel derived 0/3h-criteria for the observe-zone patients ruled out NSTEMI with a 3h hs-cTnT concentration <15 ng/L and a 0/3h-hs-cTnT absolute change <4 ng/L, triaging 138 patients (25%) toward rule-out, resulting in a sensitivity of 99.2% (95% CI, 96.0-99.9), missing 1 patient with NSTEMI. A 0/3h-hs-cTnT absolute change ≥6 ng/L triaged 63 patients (11.2%) toward rule-in, resulting in a specificity of 98% (95% CI, 96.2-98.9) Thereby, the novel 0/3h-criteria reduced the number of patients in the observe zone by 36%s and the number of type 1 myocardial infarction by 50%. Findings were confirmed in both internal and external validation.
Conclusions:
A combination of a 3h-hs-cTnT concentration (<15 ng/L) and a 0/3h absolute change (<4 ng/L) is necessary to safely rule out NSTEMI in patients remaining in the observe-zone of the ESC 0/1h-hs-cTnT-algorithm. Registration: URL: https://clinicaltrials.gov; Unique identifier: NCT00470587.
