Current status of emergency medical service use in ST-segment elevation myocardial infarction in China: Findings from China Acute Myocardial Infarction (CAMI) Registry

The mortality rate of myocardial infarction in China has increased dramatically in the past three decades. Although emergency medical service (EMS) played a pivotal role for the management of patients with ST-segment elevation myocardial infarction (STEMI), the corresponding data in China are limited. An observational analysis was performed in 26,305 STEMI patients, who were documented in China acute myocardial infarction (CAMI) Registry and treated in 162 hospitals from January 1st, 2013 to January 31th, 2016. We compared the differences such as demographic factors, social factors, medical history, risk factors, socioeconomic distribution and treatment strategies between EMS transport group and self-transport group. Only 4336 patients (16.5%) were transported by EMS. Patients with symptom onset outside, out-of-hospital cardiac arrest and presented to province-level hospital were more likely to use EMS. Besides those factors, low systolic blood pressure, severe dyspnea or syncope, and high Killip class were also positively related to EMS activation. Notably, compared to self-transport, use of EMS was associated with a shorter prehospital delay (median, 180 vs. 245 min, P