The ESC 0/1-hour diagnostic pathway did not significantly increase discharges within 4 hours compared to the 0/3-hour pathway (21.8% vs 19.2%, P=0.07) but was noninferior for 30-day safety.
RCT (n=3,543)
Randomized
Yes
Does the ESC 0/1-hour accelerated diagnostic pathway improve efficiency and maintain safety compared to a 0/3-hour pathway in patients with suspected acute coronary syndrome?
In real-world practice, implementing the 0/1-hour troponin pathway is safe but fails to significantly improve emergency department discharge times compared to the 0/3-hour pathway due to central laboratory turnaround times and system constraints.
Absolute Event Rate: 21.8% vs 19.2%
p-value: p=0.07
BACKGROUND: For suspected acute coronary syndrome (ACS), guidelines recommend using high-sensitivity troponins (hs-cTn) in accelerated diagnostic pathways (ADPs) with 0/1-hour recommended over 0/3-hour ADP. However, implementation of these ADPs, with universal use of hs-cTns, has not been directly compared in randomized trials OBJECTIVES: This study sought to compare the efficiency and safety of the European Society of Cardiology (ESC) 0/1-hour and a 0/3-hour ADP when implemented in real-world clinical practice. METHODS: This pragmatic, randomized, noninferiority implementation trial compared the safety and efficiency of clinician decision making using these 2 pathways. To prevent incorporation bias, an independent hs-cTnI was used for formal adjudication using the fourth universal definition of myocardial infarction (MI). Efficiency was judged by the proportion of patients discharged within 4 hours. The safety endpoint was major adverse cardiac events (MACE) within 30 days (adjudicated index or representation type 1 MI, cardiovascular death, and urgent coronary revascularization) for those who were considered not to have ACS and discharged. The noninferiority margin, for absolute difference in sensitivity, between the ESC 0/1-hour and the 0/3-hour ADP was set at 3%, assessed with a 1-sided 97.5% CI. RESULTS: From December 2021 to July 2024, of 13,983 screened 3,543 individual patients with suspected ACS were recruited and consented from 2 major emergency departments in North-West England, with 100% follow-up achieved for all representations to any national hospital. The median age was 60 years (IQR: 49.5-70.5 years), 53% were men, 6.9%, and 7.8% had adjudicated index type 1 MI and MACE within 30 days, respectively. The turnaround time from sample to result for central laboratory hs-cTnT was 81 minutes (IQR: 69-101 minutes). The proportion of patients discharged within 4 hours was relatively low and did not differ substantially (21.8% vs 19.2%, P = 0.07). In addition, the 0/1-hour pathway was noninferior for safety, in patients discharged, compared with the 0/3-hour pathway, absolute difference in sensitivity was +4.2% (1-sided 97.5% CI: -2.5) in favor of the 0/1-hour pathway. The calculated sensitivities were 93.7% (95% CI: 88.4%-97.1%) vs 89.5% (95% CI: 82.7%-94.3%), respectively. CONCLUSIONS: Implementation of the ESC 0/1-hour pathway failed to discharge significantly more patients within 4 hours of presentation compared with the 0/3-hour ADP. In addition, The ESC 0/1-hour was noninferior to the 0/3-hour hs-cTn pathway for safety of discharge, although safety for both pathways was less than that imputed by observational studies. This trial demonstrates that perceived benefits to emergency department efficiency of a reduced sampling interval are mitigated by central laboratory turnaround times as well as system constraints. (Pragmatic Randomised Trial of the ESC 0/1 Versus 0/3 Hour Troponin Pathway MACROS2; NCT05322395).
“The results of MACROS-2 remind us that even when clinical pathways have been validated in rigorous trials, these pathways may not perform as well in some real-world practice setting. Laboratory turnaround times, clinical decision-making and limited resources in clinical practice can challenge eff...”
Hatherley et al. (Fri,) conducted a rct in Suspected acute coronary syndrome (n=3,543). ESC 0/1-hour accelerated diagnostic pathway vs. 0/3-hour accelerated diagnostic pathway was evaluated on Proportion of patients discharged within 4 hours (p=0.07). The ESC 0/1-hour diagnostic pathway did not significantly increase discharges within 4 hours compared to the 0/3-hour pathway (21.8% vs 19.2%, P=0.07) but was noninferior for 30-day safety.