High sensitivity troponin - Six hours is the magic number

Area of Science:

• Cardiology
• Emergency Medicine
• Biomarkers

Background:

• High sensitivity troponin (hs-cTn) assays are standard in emergency departments for acute chest pain evaluation.
• Assessing the utility of hs-cTn in ruling out acute coronary syndrome (ACS) is crucial for patient management.

Purpose of the Study:

• To determine if hs-cTn below the 99th percentile upper reference limit (URL) at ≥6 hours from symptom onset can safely exclude ACS.
• To evaluate the rate of adverse cardiac events in patients with specific hs-cTn levels and ECG findings.

Main Methods:

• A multicenter retrospective study of emergency department patients with chest pain admitted for further evaluation.
• Analysis of clinically relevant adverse cardiac events and non-ST-elevation myocardial infarction (NSTEMI) in relation to hs-cTn levels ( < 99th percentile URL) at ≥6 hours post-symptom onset.

Main Results:

• Among 1187 admitted patients, 30 adverse cardiac events occurred, all in patients with compelling reasons for admission or ischemic ECG.
• Three cases of NSTEMI were observed among 429 patients with hs-cTn < 99th percentile URL at ≥6 hours, non-ischemic ECG, and no other admission indication.
• No clinically relevant adverse cardiac events were found in this low-risk subgroup.

Conclusions:

• Patients with chest pain and hs-cTn levels between 3 ng/L and the 99th percentile URL at ≥6 hours have a low incidence of adverse cardiac events and NSTEMI.
• This finding supports the safe exclusion of ACS in selected patients presenting with chest pain.