Outcomes of patients admitted with high-sensitive cardiac troponin t levels meeting the new rule out criteria for myocardial infarction

Background: The 2020 ESC non-ST-elevation (NSTE) acute coronary syndromes (ACS) guidelines have adopted the paradigm that patients presenting with suspected NSTE-ACS and high-sensitive cardiac troponin T (hs-cTnT) values <99th percentile in a single test or small increment within 1/2 hours have a high negative predictive value for myocardial infarction (MI). Their management remains controversial.

Purpose: We examined the clinical outcomes and resource utilization of suspected NSTE-ACS patients who presented with hs-cTnT values meeting the early rule out criteria, but were nevertheless admitted.

Methods: Our single center retrospective cohort study included 4,263 visits for suspected NSTE-ACS triaged in the Emergency Room (ER), had hs-cTnT values that met the early rule-out criteria, and were admitted (Figure).

Routine quality control and dedicated tests proved a coefficient of variance of <10% for hs-cTnT values < 99th percentile (14 ng/L).

Results: There were no deaths in-hospital and at 30 days. Discharge diagnosis of MI was documented in 10 patients (~0.2%). Median ER stay and hospital stay were 6 hours and 3 days, respectively. In hospital evaluation included 844 gated cardiac CT angiography, 580 SPECT heart scan, 101 ECG-exercise tests, and 178 coronary angiographies, of which 70 (~1.6% of cohort) culminated in percutaneous/surgical intervention.

Conclusion: Our findings highlight the high negative predictive value for MI applying the early rule out algorithm and supports a policy of ER discharge for further evaluation, sparing unnecessary and resource-consuming hospital admissions.