UCLA

We evaluated the first-medical-contact-to-balloon (FMC2B) time after implementation of a "Call 911" protocol for ST-segment-elevation myocardial infarction (STEMI) interfacility transfers in a regional system. This is a retrospective cohort study of consecutive patients with STEMI requiring interfacility transfer from a STEMI referring hospital, to one of 35 percutaneous coronary intervention-capable STEMI receiving centers (SRCs). The Call 911 protocol allows the referring physician to activate 911 to transport a patient with STEMI to the nearest SRC for primary percutaneous coronary intervention. Patients with interfacility transfers were identified over a 4-year period (2011-2014) from a registry to which SRCs report treatment and outcomes for all patients with STEMI transported via 911. The primary outcomes were median FMC2B time and the proportion of patients achieving the 120-minute goal. FMC2B for primary 911 transports were calculated to serve as a system reference. There were 2471 patients with STEMI transferred to SRCs by 911 transport during the study period, of whom 1942 (79%) had emergent coronary angiography and 1410 (73%) received percutaneous coronary intervention. The median age was 61 years (interquartile range [IQR] 52-71) and 73% were men. The median FMC2B time was 111 minutes (IQR 88-153) with 56% of patients meeting the 120-minute goal. The median STEMI referring hospital door-in-door-out time was 53 minutes (IQR 37-89), emergency medical services transport time was 9 minutes (IQR 7-12), and SRC door-to-balloon time was 44 minutes (IQR 32-60). For primary 911 patients (N=4827), the median FMC2B time was 81 minutes (IQR 67-97). Using a Call 911 protocol in this regional cardiac care system, patients with STEMI requiring interfacility transfers had a median FMC2B time of 111 minutes, with 56% meeting the 120-minute goal.