Abstract 12562: To Call ‘911’ or Not: What Influences Decision Making in Patients With St-Elevation Myocardial Infarction (STEMI)?

Abstract

Introduction: It is well-established that total ischemic time (TT) is related to mortality of STEMI patients treated with primary percutaneous coronary intervention (PPCI). TT is composed of the time from symptom onset (Sx) to first medical contact (FMC) and FMC to device. Shortest times are achieved when patients decide to call ‘911’, have a pre-hospital electrocardiogram and are transported directly for PPCI. Efforts have primarily focused on improvement of FMC-Device time. SxFMC time is less understood, collected and studied. Our goal was to identify factors that influence STEMI patients’ decision making to employ emergency medical services (EMS) vs self-presenting to an emergency department (ED). Methods: Between 1/1/2013- 12/31/2014, we collected data on 481 consecutive low risk STEMI patients, excluding cardiogenic shock, cardiac arrest and unsuccessful PPCI. Results: The median SxFMC was 53 minutes (interquartile range (IQR) 23-120) in EMS cohort versus 139 minutes (IQR 72-297) in ED group (p<0.001). EMS patients were more often older (median age 64, IQR 56-74 vs 60 IQR 52-68) vs ED, p<0.001. Presenting features such as sex, anterior STEMI, and Killip Class were not statistically different between EMS and ED. Risk factors (RF) for coronary disease including hypertension, dyslipidemia, diabetes, smoking, previous diagnosis of myocardial infarction (MI), previous PCI or coronary artery bypass grafting (CABG) were not statistically different between the groups. There was no difference in time of the day of symptoms onset between the groups. Conclusions: Accordingly, demographic, cardiac risk factors, time of onset of symptoms, location and severity of infarction are not associated with patient decisions to employ EMS. However, older patients were more likely to employ EMS. Further research is required to understand these decision-making processes to develop targeted public awareness interventions that are directed to improve SxFMC in STEMI patients.