Safety of a 1-hour Rule-out High-sensitive Troponin T Protocol in Patients With Chest Pain at the Emergency Department

Background: The 1-hour rule-out high-sensitive cardiac troponin T protocol (hs-cTnT), in which a serial troponin measurement is performed 1 hour after the first to assess the possibility of acute coronary syndrome (ACS), has been implemented in the European guidelines in 2015. Our aim was to assess the safety of this protocol in low-risk patients in the Emergency Department (ED) when implemented in daily practice. Methods: Patients with acute chest pain presenting to the ED of our hospital and younger than 75 years were included (May 2013 to October 2014, The Netherlands). Hs-cTnT was measured at presentation (T0) and 1-1.5 hours after T0 (T1). Patients with a first troponin (T0) ≥ 0.012 ug/l were excluded. Primary endpoint was the 6-week occurrence of major adverse cardiac events (MACEs), defined as unstable angina, acute myocardial infarction (AMI), percutaneous coronary intervention, significant stenosis managed conservatively, coronary artery bypass grafting, and death. Results: Of the 374 analyzed patients, 16 patients (4.3%) developed 35 MACE. Of these 16 patients with endpoints, 3 were primarily discharged with noncardiac chest pain but returned within 6 weeks with unstable angina. Importantly, no patients experienced an AMI or died during follow-up. Conclusion: No AMIs or deaths occurred after introducing the 1-hour hscTnT protocol to rule-out ACS in chest pain patients, but other MACE such as unstable angina occurred. Our results suggest the protocol is safe to implement in the ED in The Netherlands.