Add-on tests for improving risk-stratification in emergency department patients with chest pain who are at low to moderate risk of 30-day major adverse cardiac events

BackgroundChest pain patients commonly present to emergency departments (ED), and require either hospital admission and/or lengthy diagnostic protocols to rule-out myocardial infarction. We aimed to identify the best combination of add-on tests to high-sensitivity cardiac troponin (hs-cTnT) for predicting 30-day major adverse cardiac events (MACE) in adult chest pain patients presenting to an ED with suspected acute coronary syndrome.MethodsThis prospective observational study was conducted in the ED of a tertiary university hospital in Hong Kong, recruiting adult patients with chest pain of less than 24 h duration, suspected with acute coronary syndrome (ACS), and had no history of coronary artery bypass grafting or stent insertion. Patients underwent triage assessment, electrocardiography, blood sampling for laboratory hs-cTnT, and Thrombolysis in Myocardial Infarction (TIMI) and HEART score assessment. The primary outcome was the number of patients with 30-day MACE.Results602 consecutive patients were recruited and completed 30-day follow-up. A 30-day MACE occurred in 42 (7.0%) patients. Out of 12 possible models for stratifying patients at risk of 30-day MACE within 2 h of ED arrival, a combination of electrocardiography (ECG) and one-time hs-cTnT (model 5) provided the simplest and most accurate model. A risk score of 0 to 5 was derived from raw coefficients of model 5. The risk score provided excellent calibration (P = 0.91) and discrimination (AUC 0.87, 95% CI: 0.82 to 0.93).ConclusionAppropriate early risk-stratification of patients with chest pain and possible ACS using a combination of ECG and one-time hs-cTnT may improve efficiency of care.