Abstract 549: ST-Segment Analysis Using Wireless Technology in Acute Myocardial Infarction (STAT-MI) Trial: Early vs. Late Experience
Background: We previously reported our early (initial 6 month) experience using a fully automated wireless network to shorten door to intervention (D2I) times. Later experience allowed for further refinement of this network. Early D2I times are expected to result in smaller infarcts and decreased lengths of stay.
Methods: A fully automated wireless network that facilitates simultaneous 12-lead ECG transmission from emergency medical services (EMS) personnel in the field to the Emergency Department (ED) and offsite cardiologists via smart phones. This allows direct communication between offsite cardiologist and EMS and facilitates patient triage directly to the cath lab. Demographic, laboratory and time interval data were prospectively collected over a 23-month period and compared to calendar year 2005 data. Early experience (first 6 months) was compared to later experience.
Results: From June 2006 through April 2008, 242 ECGs with suspected ST segment elevation myocardial infarction (STEMI) were transmitted via the STAT-MI network. Compared with 2005 data, door to cardiology notification time was reduced from 61.4 minutes (min) to −15.8 min (p < 0.001), door to arterial access time decreased from 108.1 to 42.1 min (p < 0.0001), door to intervention (D2I) time decreased from 145.7 to 68.8 min (p = 0.00001), hospital length of stay decreased from 5.4 ± 4.5 days to 4.1 ± 5.0 days (p < 0.29), and troponin elevation decreased from 106.4 ng/ml to 73.9 ng/ml (p < 0.19). The magnitude of timesavings was similar regardless of time of presentation, though D2I times were longer during “off” hours (after 5pm and weekends) as compared to “on” hours (85.7 min vs. 51.8 min P=0.001). Protocol refinements introduced over the first 6 months further shortened D2I times; 87 min vs 65 min in the first 6 months and in the subsequent 17 months respectively (p = 0.09).
Conclusions: A fully automated wireless network that transmits ECGs simultaneously to the ED and offsite cardiologists for the early evaluation and triage of patients with STEMI markedly and consistently shortened D2I times. A strong positive trend in outcome measures was also observed with reduced length of stay and smaller infarct size. There was a 6 month learning curve to fully realize the benefits of this new automated system.