The Evolution of Accelerated Diagnostic Protocols for Suspected Myocardial Infarction

There have been considerable developments in the analytic precision of cardiac troponins in the last three decades. Whilst there has been near-universal uptake of this technology, there is considerable variability in how to assess acute chest pain patients using high-sensitivity cardiac troponins. This review describes the historical narrative for cardiac troponins and details the evidence base behind decision rules, such as single sample rule-out, single sample rule-in, and accelerated diagnostic protocols (ADPs). There is particular focus on the European Society of Cardiology (ESC) 0/1 and 0/3 h and the high-STEACS ADPs. The ESC 0/3 h ADP appears to have reduced rule-out safety compared to both the ESC 0/1 h and high-STEACS ADP. However, whilst high-STEACS performed well in its validation population, external validation in the US has been less impressive and warrants further investigation. The ESC 0/1 h pathway has demonstrated strong rule-out performance, helped by its observational zone. However, real world implementation studies comparing these ADPs are required to understand their impact on Emergency Department efficiency and the safety of clinician decision-making.