USEFULNESS OF PRE-HOSPITAL ECG IN STEMI PATIENTS PRESENTING DIRECTLY TO A PRIMARY PCI CENTER

Abstract

Shorter reperfusion times are associated with improved clinical outcomes in STEMI patients referred for primary PCI. Patients presenting to hospitals without PCI facilities experience additional delays associated with transportation to primary PCI centers. The use of pre-hospital ECG to identify patients with STEMI may help reduce reperfusion times by taking patients directly to hospitals performing primary PCI. Whether pre-hospital ECG may also improve reperfusion delays in patients who would normally present directly to a primary PCI center is unclear. Between July 2012 and June 2013, 689 patients were admitted with a diagnosis of STEMI in a single tertiary cardiology care center. A total of 286 patients were excluded: 159 treated with thrombolysis, 65 with late presentation, 28 referred from outside a radius of 90 min transport time, 7 developing STEMI in-hospital, 6 with spontaneous ST-segment resolution, and 21 patients with missing data. We compared 161 patients who underwent pre-hospital 12-lead ECG in the ambulance and were oriented directly to the primary PCI-capable center (pre-hospital ECG group) with 242 patients who presented to a referral hospital or directly to the primary PCI center but did not benefit from pre-hospital ECG (control group). Median first door-to-balloon (DTB) time was shorter in the pre-hospital ECG group (46 min vs 102 min;p<0.001). Pre-hospital ECG also reduced median first-medical-contact-to-balloon from 115 min to 84 min (p<0.001). Proportion of patients with DTB time < 90 minutes was 98% in the pre-hospital ECG group and 45% in the control group (p<0.001). Total ischemic time, defined by the time between symptom onset and device activation, was also reduced by a median of 111 minutes in patients with pre-hospital ECG (140 vs 246 minutes; p<0.001). In an analysis restricted to patients living on the territory of the primary PCI center, pre-hospital ECG significantly reduced median DTB (80 min vs 50 min; p<0.001), median first-medical-contact-to-balloon (102 min to 79 min; p<0.001) and median total ischemic time (220 min vs 116 min;p<0.001). Pre-hospital ECG significantly reduces reperfusion delays in STEMI patients. Benefits are seen in all patients, including those who would normally present directly to a primary PCI center. Broader use of this technology should be supported and efforts should be made to encourage patients to use emergency medical service if they experience chest pain suggestive of heart attack.