Use of troponin assay after electrical injuries: a 15-year multicentre retrospective cohort in emergency departments

Abstract

Background: Patients with electrical injury are considered to be at risk of cardiac arrhythmia. Assessing the risk of developing a major adverse cardiac event (MACE) is the cornerstone of patient management. The aim of this study was to assess the performance of initial troponin and troponin rise to predict Major Adverse Cardiac Events (MACEs) in all patients with electrical injuries admitted to the Emergency Department.

Methods: This is a multicentre retrospective study in which consecutive patients with electrical injuries admitted to the Emergency Departments (ED) (adult and paediatric) of five French Hospitals were included between 2005 and 2019. The threshold for troponin elevation is based on the European Society of Cardiology guidelines for patients presenting without persistent ST segment elevation. The primary endpoint was the rate of MACE.

Results: A total of 785 included patients were admitted to ED with a first diagnosis of electrical injury during the study period. Troponin assays were performed in 533 patients (67.9%), including 465 of 663 adults (70.1%) and 68 of 122 children (55.7%) and 17/533 (3.2%) of patients had an initial elevated troponin. If none of the clinical criteria for MACE were present (i.e., previous known heart disease, exposure to a high voltage of ≥ 1000 Volts, initial loss of consciousness, or an abnormal initial ECG), this defined a low-risk subgroup (n = 573, 76.0%) that could be safely discharged. The initial positive troponin assay had a sensitivity of 83.3 (95% CI 35.9-99.6%), a specificity of 97.7 (95% CI 96.1-98.8%), a positive likelihood ratio 36.6 (95% CI 18.8-71.1%) and a negative predictive value of 99.9 (95% CI 99.2-99.9%) in predicting a MACE.

Conclusions: Troponin assay appears to be a predictive marker of MACE risk and should be considered in high-risk patients.

Keywords: Cardiac arrhythmias; Electric injuries; Emergency Department; MACE; Troponin.

Fig. 1

Flow diagram. *According to the 4 high-risk clinical items combined (previous known heart disease, exposure to a high voltage of ≥ 1000 V, initial loss of consciousness, abnormal initial ECG); if ≥ 1 items = high risk patients. Missing data, n = 31. **Initial elevated troponin and/or significant rise on the 2nd essay. MACE Major Adverse Cardiac Even

Fig. 2

Flowchart for a standard protocol for patients with electrical injury (based on the paper by Waldmann et al. [1]). *No prospective data available, a procedure in line with the acute coronary syndrome is recommended: follow-up 12-channel ECG, troponin after 6 h and, if necessary, after 12–24 h (ERC)