Performance of Emergency Department Screening Criteria for an Early ECG to Identify ST‐Segment Elevation Myocardial Infarction

Abstract

BackgroundTimely diagnosis of ST‐segment elevation myocardial infarction (STEMI) in the emergency department (ED) is made solely by ECG. Obtaining this test within 10 minutes of ED arrival is critical to achieving the best outcomes. We investigated variability in the timely identification of STEMI across institutions and whether performance variation was associated with the ED characteristics, the comprehensiveness of screening criteria, and the STEMI screening processes.Methods and ResultsWe examined STEMI screening performance in 7 EDs, with the missed case rate (MCR) as our primary end point. The MCR is the proportion of primarily screened ED patients diagnosed with STEMI who did not receive an ECG within 15 minutes of ED arrival. STEMI was defined by hospital discharge diagnosis. Relationships between the MCR and ED characteristics, screening criteria, and STEMI screening processes were assessed, along with differences in door‐to‐ECG times for captured versus missed patients. The overall MCR for all 7 EDs was 12.8%. The lowest and highest MCRs were 3.4% and 32.6%, respectively. The mean difference in door‐to‐ECG times for captured and missed patients was 31 minutes, with a range of 14 to 80 minutes of additional myocardial ischemia time for missed cases. The prevalence of primarily screened ED STEMIs was 0.09%. EDs with the greatest informedness (sensitivity+specificity−1) demonstrated superior performance across all other screening measures.ConclusionsThe 29.2% difference in MCRs between the highest and lowest performing EDs demonstrates room for improving timely STEMI identification among primarily screened ED patients. The MCR and informedness can be used to compare screening across EDs and to understand variable performance.

Measuring outcome differences associated with STEMI screening and diagnostic performance: a multicentred retrospective cohort study protocol

“…It is typical practice in EDs for ECGs to be taken directly to an emergency physician for interpretation. 14–17 Door-to-diagnosis (D2D) is the interval from ED arrival to STEMI diagnosis ( table 1 ). STEMI diagnosis is defined as the time when the physician activates a cardiac lab team for emergent PCI.…”

“…Given the European Heart Association, American College of Cardiology and American Heart Association recommendation to obtain an early ECG within 10 min for patients with symptoms suggestive of STEMI, 2–4 nearly 85% of EDs have protocols to guide the screen of all arriving patients for the need of an early ECG. 14 We define an early ECG as one performed upon ED arrival, typically well before physician evaluation, to diagnose STEMI in a timely fashion. 14–16 Our prior work identified 12.8% (95% CI 3.4% to 32.6%) of patients with STEMI do not receive a timely ECG.…”

“… 14 We define an early ECG as one performed upon ED arrival, typically well before physician evaluation, to diagnose STEMI in a timely fashion. 14–16 Our prior work identified 12.8% (95% CI 3.4% to 32.6%) of patients with STEMI do not receive a timely ECG. The resulting diagnostic delay led to 14–80 minutes of additional myocardial ischaemia time.…”

“…The resulting diagnostic delay led to 14–80 minutes of additional myocardial ischaemia time. 14 Earlier treatment has been historically associated with better outcomes. 2 3 The degree to which timely screening and diagnosis are associated with improved time to intervention and post-PCI outcomes, under more contemporary practice conditions, is not known.…”

Acute Coronary Syndrome Screening and Diagnostic Practice Variation

“…There are ongoing efforts within institutions to streamline screening and diagnosis to better align resources used for this evaluation with diagnostic yield. Despite the need for flexibility in the implementation of clinical practice across EDs with different resources and capabilities, current clinical evidence provides opportunities to reduce variations for this well‐researched disease process across EDs . Reducing practice variability for clinical decisions supported with evidence may improve care quality and consistency .…”