Factors associated with longer time to treatment for patients with suspected acute coronary syndromes: a cohort study.

BACKGROUND Rapid treatment of acute coronary syndromes (ACS) is important; causes of delay in emergency medical services care of ACS are poorly understood. METHODS AND RESULTS We performed an analysis of data from IMMEDIATE (Immediate Myocardial Metabolic Enhancement during Initial Assessment and Treatment in Emergency Care), a randomized controlled trial of emergency medical services treatment of people with symptoms suggesting ACS, using hierarchical multiple regression of elapsed time. Out-of-hospital ECGs were performed on 54,230 adults calling 9-1-1; 871 had presumed ACS, 303 of whom had ST-segment elevation myocardial infarction and underwent percutaneous coronary intervention. Women, participants with diabetes mellitus, and participants without previous cardiovascular disease waited longer to call 9-1-1 (by 28 minutes, P<0.01; 10 minutes, P=0.03; and 6 minutes, P=0.02, respectively), compared with their counterparts. Time from emergency medical services arrival to ECG was longer for women (1.5 minutes; P<0.01), older individuals (1.3 minutes; P<0.01), and those without a primary complaint of chest pain (3.5 minutes; P<0.01). On-scene times were longer for women (2 minutes; P<0.01) and older individuals (2 minutes; P<0.01). Older individuals and participants presenting on weekends and nights had longer door-to-balloon times (by 10, 14, and 11 minutes, respectively; P<0.01). Women and older individuals had longer total times (medical contact to balloon inflation: 16 minutes, P=0.01, and 9 minutes, P<0.01, respectively; symptom onset to balloon inflation: 31.5 minutes for women; P=0.02). CONCLUSIONS We found delays throughout ACS care, resulting in substantial differences in total times for women and older individuals. These delays may impact outcomes; a comprehensive approach to reduce delay is needed.