We tested the hypothesis that patients with a potential acute coronary syndrome (ACS) and very low levels of high-sensitivity cardiac troponin I can be efficiently and safely discharged from the emergency department after a single troponin measurement.This prospective cohort study recruited 2255 consecutive patients aged ≥18 years presenting to the Emergency Department, Royal Perth Hospital, Western Australia, with chest pain without high-risk features but requiring the exclusion of ACS. Patients were managed using a guideline-recommended pathway or our novel Single Troponin Accelerated Triage (STAT) pathway. The primary outcome was the percentage of patients discharged in <3 hours. Secondary outcomes included the duration of observation and death or acute myocardial infarction in the next 30 days.The study enrolled 1131 patients to the standard cohort and 1124 to the STAT cohort. Thirty-eight per cent of the standard cohort were discharged directly from emergency department compared with 63% of the STAT cohort (p<0.001). The median duration of observation was 4.3 (IQR 3.3-7.1) hours in the standard cohort and 3.6 (2.6-5.4) hours in the STAT cohort (p<0.001), with 21% and 38% discharged in <3 hours, respectively (p<0.001). No patients discharged directly from the emergency department died or suffered an acute myocardial infarction within 30 days in either cohort.Among low-risk patients with a potential ACS, a pathway which incorporates early discharge based on a single very low level of high-sensitivity cardiac troponin increases the proportion of patients discharged directly from the emergency department, reduces length of stay and is safe.ACTRN12618000797279.