Influence of ambulance use on early reperfusion therapies for acute myocardial infarction

Background Ambulance use expedites the definitive treatment of acute myocardial infarction （AMI）. The aim of this study was to evaluate the effect of ambulance use on the administration of early reperfusion therapies for patients with AMI in Beijing, China. Methods Data were prospectively collected from 498 patients with ST-elevation myocardial infarction （STEMI） who were admitted within 12 hours of symptom onset to 19 hospitals in Beijing between November 1,2005 and December 31, 2006. The baseline characteristics of and the initial management of the ambulance users and the non-ambulance users were compared. Results Only 186 （37.3%） patients used an ambulance as transportation to the hospital. Ambulance users were, on average, older and at relatively higher risk on presentation than the non-ambulance users. After adjustment for patient and hospital characteristics, ambulance use was associated with a greater early reperfusion rate, mainly because of a greater incidence of primary percutaneous coronary intervention. In addition, ambulance users had a significantly shorter median door-to-balloon （120 compared with 145 minutes, P 〈0.001） and symptom onset-to-balloon （223 compared with 300 minutes, P 〈0.001） time than non-ambulance users. Conclusions Ambulances are underused by AMI patients in Beijing. Ambulance use may lead to more frequent and faster receipt of early reperfusion therapies. New public health strategies should be developed to facilitate an increased use of ambulances by AMI patients.