Impact of Patient- and System-Level Delays on Reperfusion Among Patients With ST-Elevation Myocardial Infarction

BACKGROUND: Patients with ST-elevation myocardial infarction (STEMI) presenting to percutaneous coronary intervention (PCI)-capable hospitals often experience delays for primary PCI (pPCI). We sought to describe the effect of specific delay intervals and patient/system-level factors on STEMI reperfusion times. METHODS: We analyzed all consecutive patients with STEMI who presented to 2 PCI-capable hospital emergency departments (EDs) between June 2007 and March 2016 who received successful pPCI. We excluded patients with prehospital cardiac arrest. We compared specific system delay intervals, patient characteristics, and in-hospital outcomes among patients who received timely (first medical contact-device ≤90/≤120 minutes) vs delayed >90/>120 minutes) pPCI. RESULTS: Of 1936 patients with STEMI, 1127 (58%) presented directly to a PCI-capable hospital via emergency health services (EHS), 499 (26%) were transferred from the ED of a non-PCI hospital, and 310 (16%) self-presented to the ED of a pPCI-capable hospital. Guideline-recommended reperfusion times were met in 47% of direct-EHS, 42% of transfers, and 33% of self-presenters. Each time interval from first medical contact to device deployment was significantly prolonged in the delayed vs timely reperfusion cohorts across all 3 groups, excepting vascular access time. ED dwell time contributed the most to the difference in median reperfusion time within each group. Time of presentation, comorbidities, and sex were each significantly associated with delayed reperfusion. Within the EHS-direct group, prolonged reperfusion and ED dwell times were significantly associated with increased mortality, major bleeding, and cardiogenic shock. CONCLUSION: Ongoing efforts to identify and reduce ED dwell time and other systemic pPCI delays may improve STEMI outcomes, including mortality.