top of page

Flattening the other curve: Reducing emergency department STEMI delays during the COVID-19 pandemic

UHN-JM-Reducing STEMI Delays


Background: The COVID-19 pandemic has been associated with ST-Elevation Myocardial Infarction (STEMI) reperfusion delays despite reduced emergency department (ED) volumes. However, little is known about ED contributions to these delays. We sought to measure STEMI delays and ED quality benchmarks over the course of the first two waves of the pandemic. 

Study: This study was a multi-centre, retrospective chart review from two urban, academic medical centres. We obtained ED volumes, COVID-19 tests and COVID-19 cases from the hospital databases and ED Code STEMIs with culprit lesions from the cath lab. We measured door-to-ECG (DTE) time and ECG-to-Activation (ETA) time during the phases of the pandemic in our jurisdiction: pre-first wave (Jan-Mar 2020), first wave (Apr-June 2020), post-first wave (July-Nov 2020), and second wave (Dec 2020 to Feb 2021). We calculated median DTE and ETA times and compared them to the 2019 baseline using Wilcox rank-sum test. We calculated the percentages of DTE <= 10 min and of ETA <=10 min and compared them to baseline using chi-square test. We also utilized Statistical Process Control (SPC) Xbar-R charts to assess for special cause variation. Results COVID-19 cases began during the pre-wave phase, but there was no change in ED volumes or STEMI quality metrics. During the first wave ED volumes fell by 40%, DTE tripled (10.0 to 29.5 min, p = 0.016), ETA doubled (8.5 to 17.0 min, p = 0.04), and percentages for both DTE <=10 min and ETA <= 10 min fell by three-quarters (each from more than 50%, to both 12.5%, both p < 0.05). After the first wave all STEMI quality benchmarks returned to baseline and did not significantly change during the second wave. A brief period of special cause variation was noted for DTE during the first wave. Conclusions Both DTE and ETA metrics worsened during the first wave of the pandemic, revealing how it negatively impacted the triage and diagnosis of STEMI patients. But these normalized after the first wave and were unaffected by the second wave, indicating that nurses and physicians adapted to the pandemic to maintain STEMI quality of care. DTE and ETA metrics can help EDs identify delays to reperfusion during the pandemic and beyond.

Authors: Jesse T.T. McLaren, Ahmed K.Taher, Lucas B.Chartier

Jesse McLaren -

Preliminary data gathering/ baseline

bottom of page