Lack of Significant Coronary History and ECG Misinterpretation Are the Strongest Predictors of Undertriage in Prehospital Chest Pain

Abstract

Introduction: Appropriate prehospital (PH) triage of patients with chest pain can significantly improve outcomes in acute myocardial infarction (MI). We sought to explore how PH providers triage chest pain as high versus low risk and to evaluate the accuracy and predictors of their triage decision. Methods: This was a prospective, observational cohort study that enrolled consecutive patients with chest pain transported by emergency medical services (EMS) to 3 tertiary care hospitals in the US. EMS triage decision (high risk versus low-risk) was defined based on the transmission of PH electrocardiogram (ECG) to a command center for medical consultation with or without catheter laboratory activation. Two independent reviewers examined in-hospital medical records to adjudicate the presence of acute MI and to audit the findings on the presenting ECG. Results: We enrolled 2,065 patients (aged 56 ± 17, 53% male) of whom 768 (37%) were triaged as high risk. Those triaged as high risk were older, were more likely to be men or have significant cardiac history, and had a higher rate of acute MI events(14.2% versus 3.5%). The sensitivity and specificity for triaging MI events as high risk were 70% and 97%, respectively. A total of 46/155 (30%) MI events were misclassified as low risk. No previous coronary revascularization and ECG misinterpretation were strong independent predictors of such undertriage. Conclusions: PH providers have moderate sensitivity in triaging high-risk patients; 1 in 3 MI events are undertriaged. Emergency nurses need to pay special attention to patients with benign past histories during transition of care and should always reinterpret ECGs for subtle ischemic changes.

Electrocardiogram interpretation competency among emergency nurses and emergency medical service (EMS) personnel: A cross‐sectional and comparative descriptive study

“…This finding is shared with the findings by Faramand et al. (2019) in which EMS personnel's ECG interpretation competency was lower than that of hospital emergency nurses (Faramand et al., 2019). Similarly, the results of the study by Werner et al.…”

ECG-based Characteristics of Death or Re-infarction on the 12-Lead or 15-Lead ECG among UA/NSTEMI Patients: A Protocol for a Systematic Review and Meta-Analysis

“…Some characteristics of the ECG have a low sensitivity for a true infarction because the standard 10-second ECG is simply a snapshot of a very dynamic process [12,13,16]. Furthermore, the standard 12-lead ECG does not have posterior leads and can be easily misinterpreted [14,15]. Novel characteristics such as QRS-T angle on the 12-lead ECG have improved sensitivity and can overcome some of these other limitations [16].…”

“…Though AHA/ACC guidelines consider it reasonable to place leads over the posterior wall (V7-V9), it is not necessarily performed in clinical practice [2,14]. Lastly, the ECG is often misinterpreted by providers further leading to treatment delays [14,15]. Newer research has identi ed novel characteristics on the ECG related to UA/NSTEMI which have higher sensitivity and the potential to overcome these identi ed limitations [12,16].…”

SIM-ECG: A Signal Importance Mask-driven ECGClassification System

“…However, this is not the case quite frequently. A recent study found that 30% of myocardial infarction events were misclassified as low risk, with ECG misinterpretation responsible for half of the misclassifications [7]. Misdiagnosis is also a top concern expressed by cardiac patients [9].…”