Timeliness of interfacility transfer for ED patients with ST-elevation myocardial infarction

Most US hospitals lack primary percutaneous coronary intervention (PCI) capabilities to treat patients with ST-elevation myocardial infarction (STEMI) necessitating transfer to PCI-capable centers. Transferred patients rarely meet the 120-minute benchmark for timely reperfusion, and referring emergency departments (EDs) are a major source of preventable delays. We sought to use more granular data at transferring EDs to describe the variability in length of stay at referring EDs.

We retrospectively analyzed a secondary data set used for quality improvement for patients with STEMI transferred to a single PCI center between 2008 and 2012. We conducted a descriptive analysis of the total time spent at each referring ED (door-in-door-out [DIDO] interval), periods that comprised DIDO (door to electrocardiogram [EKG], EKG-to-PCI activation, and PCI activation to exit), and the relationship of each period with overall time to reperfusion (medical contact-to-balloon [MCTB] interval).

We identified 41 EDs that transferred 620 patients between 2008 and 2012. Median MCTB was 135 minutes (interquartile range [IQR] 114,172). Median overall ED DIDO was 74 minutes (IQR 56,103) and was composed of door to EKG, 5 minutes (IQR 2,11); EKG-to-PCI activation, 18 minutes (IQR 7,37); and PCI activation to exit, 44 minutes (IQR 34,56). Door-in door-out accounted for the largest proportion (60%) of overall MCTB and had the largest variability (coefficient of variability, 1.37) of these intervals.

In this cohort of transferring EDs, we found high variability and substantial delays after EKG performance for patients with STEMI. Factors influencing ED decision making and transportation coordination after PCI activation are a potential target for intervention to improve the timeliness of reperfusion in patients with STEMI.