Implementing the European Society of Cardiology 0-h/1-h algorithm in patients presenting very early after chest pain

The European Society of Cardiology (ESC) recommends a 0-h/1-h (0/1-h) algorithm to classify patients with suspected non-ST-segment elevation myocardial infarction (NSTEMI). However, reliable evidence about patients who present early after the onset of symptoms is limited, likely because high-sensitivity cardiac troponin (hs-cTn) values cannot increase sufficiently within that time. This study aimed to evaluate the outcomes in real-world situations that utilized the 0/1-h algorithm. In a prospective, international, multicenter cohort study that enrolled 1638 patients presenting with acute chest pain to the emergency department, we assessed the performance of the 0/1-h algorithm using hs-cTnT and the associated 30-day rates of major adverse cardiac events: death and acute myocardial infarction (AMI). Among 1074 patients, the prevalence of AMI was 16.0%. An approximately 60.1% (n = 645) of patients visited the hospital within 3 h after onset of chest pain (less than 1 h; 18.2% [n = 196], less than 2 h; 27.5% [n = 295], and less than 3 h; 14.3% [n = 154]). Moreover, the prevalence rates of AMI were similar at all times (1 h, 16.8%; 1–2 h, 20.7%; 2–3 h, 18.2%; p = .5). According to the ESC 0/1-h algorithm, the distribution patterns of rule-out, observe, and rule-in groups were similar; however, none of the patients was diagnosed with AMI or cardiac death in the rule-out group. This study revealed the applicability of the 0/1-h algorithm for the management of early presenters. •None of the 30-day major advanced cardiac events was associated with the 0/1-h algorithm for the management of very early presenters.•A distribution patterns of rule-out, observe, and rule-in groups were similar at 1 h, 1–2 h, and 2–3 h after chest pain onset.•Strategies that incorporate a HEART score with the algorithm can be used for clinical implementation.