Objective: To determine the feasibility of using a biomarker panel of myoglobin, creatinine kinase MB (CK-MB) and cardiac troponin I (cTnI) to identify patients with suspected acute coronary syndrome (ACS) who are suitable for discharge within 2 h.
Methods: We took blood at presentation and at 2 h from patients with suspected ACS and non-diagnostic electrocardiogram who were admitted to the ED short stay ward for serial electrocardiogram and troponin testing. We used a point-of-care device that gives rapid estimation of myoglobin, CK-MB and cTnI (Triage cardiac panel). These results were compared with the results of our standard hospital cardiac troponin T assay. Patients were followed up by telephone at 30 days.
Results: The study group comprised 100 patients (61 men) with mean age of 58 years. Six had a troponin-positive ACS during their ED stay. One additional patient died of a myocardial infarction within the follow-up period. The Triage panel at 2 h after presentation predicted 12-h cardiac troponin T elevation (sensitivity 100%, negative predictive value 99%) and 30-day events (sensitivity 86%, negative predictive value 97%). The majority of patients were ultimately suitable for discharge.
Conclusion: Serial myoglobin, CK-MB and cTnI have the potential to identify patients who are suitable for early discharge and outpatient work-up. A large multicentre study is required.