Outcomes in ED patients with non-specific ECG findings and low high-sensitivity troponin.

Background: Although some emergency department risk stratification tools consider non-specific ECG findings as an aid in disposition decisions, their clinical value in patients with an initially low high-sensitivity cardiac troponin I (hsTnI) is unclear.
Objective: Our purpose was to determine if non-specific ECG (ns-ECG) findings are associated with 30-day major adverse cardiac events (MACE) in ED patients presenting with suspected acute coronary syndromes (ACS) who have a low initial hsTnI.
Methods: Using the prospective Siemens Atellica hsTnI Food and Drug Administration submission observational database, we conducted a retrospective cohort study of the association between ns-ECG findings (defined as left bundle branch block [LBBB], ST depression [STD], or T-wave inversions [TWI]) and 30-day MACE (death, myocardial infarction, heart failure hospitalization, or coronary revascularization). Eligible patients presented with suspected ACS to one of 29 US EDs from April 2015 to April 2016, had stable vital signs, a blood sample for hsTnI (Siemen's Atellica, Siemens Healthineers, Inc, Malvern, PA) obtained at 1, 3, and 6 hours after ED presentation, and were followed for 30 days. The relationship between 30-day outcome, initial hsTnI, and ns-ECG was evaluated using chi-square testing.
Results: Of 2676 enrolled, 1313 patients met the inclusion criteria and are included in the analysis. Median (interquartile range) age was 62 years (54, 72), 54% were male, with 56% white, and 39% African American. Median (interquartile range) times from symptom onset to presentation and presentation to specimen collection were 92 (0, 216) and 146 (117, 177) minutes, respectively. The most common presenting symptoms were chest pain (84%), followed by dyspnea (9%). ECG findings were categorized as T-wave inversion or non-specific T wave changes (42%), ST depression ns-ECG ST changes (16%), or LBBB (2%). Thirty-day MACE occurred in 72 (5.5%) patients, with coronary revascularization (35 patients, 2.7%) and heart failure (25 patients, 1.9%) being the most frequent outcomes. In patients with an initial hsTnI below the limit of quantitation (LOQ) of 2.5 ng/L (n = 449), there was no association between ns-ECG changes and 30-day MACE ( P  = 0.42). If the hsTnI was ≥LOQ (2.5 ng/L), there were increased rates of 30-day MACE and ns-ECG findings ( P  = 0.01).
Conclusion: In ED suspected ACS patients without unstable vital signs, and an initial hsTnI less than the LOQ (2.5 ng/L), ns-ECG findings are not associated with 30-day major adverse cardiac events. The use of ns-ECG findings in ACS disposition should be considered in the context of hsTnI levels.
Competing Interests: Lamees Alshaikh: The author has no disclosures to report. Fred Apple: Board of Directors: HyTest Ltd; associate editor: Clinical Chemistry; Advisory Boards: Instrumentation Laboratory, Siemens Healthineers, Osler Diagnostics, Qorvo; Honorarium for Speaking at Industry Conferences: Siemens Healthineers, Abbott Diagnostics; principal investigator on Industry Funded Grants (non‐salaried) on cardiac biomarkers through Hennepin Healthcare Research Institute: Abbott Diagnostics, Abbott POC, BD, Beckman Coulter, Ortho‐Clinical Diagnostics, Roche Diagnostics, Siemens Healthcare, ET Healthcare, Qorvo. Frank Peacock: Research Grants: Abbott, Becton Dickenson, Brainbox, Calcimedica, CSL Behring, Cue, Ortho Clinical Diagnostics, Relypsa, Roche, Salix, Siemens. Consultant: Abbott, Astra‐Zeneca, Beckman, Bosch, Fast Biomedical, Forrest Devices, Ischemia Care, Dx, Instrument Labs, Janssen, Nabriva, Ortho Clinical Diagnostics, Osler, Relypsa, Roche, Quidel, Salix, Siemens, Upstream. Stock/Ownership Interests: AseptiScope Inc, Brainbox Inc, Braincheck Inc, Coagulo Inc, Comprehensive Research Associates LLC, Comprehensive Research Management Inc, Emergencies in Medicine LLC, Fast Inc, Forrest Devices, Ischemia DX LLC, Lucia Inc, Prevencio Inc, ScPharma, Trivirum Inc, Upstream Inc. Christopher R. deFilippi: Research funding to Inova fromAbbott Diagnostics, Roche Diagnostics, Siemens Healthineers, and Ortho Diagnostics, and consults for FujiRebio, Roche Diagnostics, Siemens Healthineers, and Ortho Diagnostics. James McCord: Research Support: Beckman, Abbott, Siemens, Roche. Consulting: Beckman, Roche. Richard Nowak: The author has no disclosures to report. Robert H. Christenson: Consultant: Roche Diagnostics, Siemens Healthineers, Quidel Diagnostics, Sphingotech, Becton Dickinson, Beckman Coulter. Scientific Advisory Board: Roche Diagnostics, Siemens Healthineers, Quidel Diagnostics, Sphingotech, Becton Dickinson. Alexander T. Limkakeng: Research funding from the following entities: Roche Diagnostics, Inc., Abbott Laboratories 2020‐now, Siemens Healthcare Diagnostics until 2020, Bristol Meyers Squibb 2019–2020, GE 2019—2020, Astrazeneca 2019—2020, Forest Devices, Inc: 2019—2020, Department of Defense/Henry Jackson Foundation, National Institutes of Health, Regeneron, Becton Dickinson.
(© 2022 The Authors. JACEP Open published by Wiley Periodicals LLC on behalf of American College of Emergency Physicians.)