Rural EMS STEMI Patients - Why the Delay to PCI?

Background: The objective of this study is to identify patient and EMS agency factors associated with timely reperfusion of patients with ST-elevation myocardial infarction (STEMI). Methods: We conducted a cohort study of adult patients (>= 18 years old) with STEMI activations from 2016 to 2020. Data was obtained from a regional STEMI registry, which included eight rural county EMS agencies and three North Carolina percutaneous coronary intervention (PCI) centers. On each patient, prehospital and in-hospital time intervals were abstracted. The primary outcome was the ability to achieve the 90-minute EMS FMC to PCI time goal (yes vs. no). We used generalized estimating equations accounting for within-agency clustering to evaluate the association between patient and agency factors and meeting first medical contact (FMC) to PCI time goal while accounting for clustering within the agency. Results: Among 365 rural STEMI patients 30.1% were female (110/365) with a mean age of 62.5 +/- 12.7 years. PCI was performed within the time goal in 60.5% (221/365) of encounters. The FMC to PCI time goal was met in 45.5% (50/110) of women vs 69.8% (178/255) of men (p < 0.001). The median PCI center activation time was 12 min (IQR 7-19) in the group that received PCI within the time goal compared to 21 min (IQR 10-37) in the cohort that did not. After adjusting for loaded mileage and other clinical variables (e.g., pulse rate, hypertension etc.), the male sex was associated with an improved chance of meeting the goal of FMC to PCI (aOR: 2.94; 95% CI 2.11-4.10) compared to the female sex. Conclusion: Nearly 40% of rural STEMI patients transported by EMS failed to receive FMC to PCI within 90 min. Women were less likely than men to receive reperfusion within the time goal, which represents an important health care disparity.