Direct comparison of the European Society of Cardiology 0/1-hour versus 0/2-hour algorithms in acute chest pain patients

Background The recent guidelines from European Society of Cardiology recommends using high-sensitivity cardiac troponin (hs-cTn) in either 0/1-hour or 0/2-hour algorithms to identify or rule out acute myocardial infarction (AMI). Several studies have shown good diagnostic accuracy with both algorithms, but few have compared the algorithms directly. Objective We aimed to compare the diagnostic accuracy of the algorithms head-to-head, in the same patients. Methods This was a secondary analysis of data from a prospective observational study. 1167 consecutive patients presenting with chest pain to the emergency department at XXX, were enrolled. Only patients with a hs-cTnT sample at presentation AND after 1 AND 2 hours were included in the analysis. We compared sensitivity, specificity, negative (NPV) and positive predictive value (PPV). The primary outcome was index visit AMI. Results A total of 710 patients were included of whom 56 (7.9%) had AMI. Both algorithms had a sensitivity of 98.2% and a NPV of 99.8% for ruling out AMI, but the 0/2-hour algorithm ruled out significantly more patients (69.3% vs 66.2%, p<0.001). For rule-in, the 0/2-hour algorithm had higher PPV (73.4% vs 65.2%) and slightly better specificity (97.4% vs 96.3%, p=0.016) than the 0/1-hour algorithm. Conclusion Both algorithms had good diagnostic accuracy, with a slight advantage for the 0/2-hour algorithm. Which algorithm to implement may thus depend on practical issues such as the ability to exploit the theoretical time saved with the 0/1-hour algorithm. Further studies comparing the algorithms in combination with ECG, history or risk scores are needed.