Study objective: Although specific cardiac injury markers have enhanced early patient classification, the ECG remains a necessary investigation in the acute phase of chest pain. Combined use of both tests could further improve the diagnostic and prognostic accuracy.
Methods: We studied 311 consecutive patients who came to the emergency department of a regional referral hospital for the differential diagnosis of acute chest discomfort. The admission ECG was classified using an automated interpretation program and tested together with elevated admission creatine kinase isoform MB (CK-MB) and cardiac troponin I (TnI) concentration for prediction of final myocardial injury (44%) and in-hospital mortality (14%).
Results: Combining the information from the admission ECG and cardiac markers, the sensitivity for becoming final myocardial injury (maximal CK-MB >/=11 microg/L) was 90% and specificity 61%. The proportion of false-negative results (10%) was independent of symptom duration. Age, positive ECG findings, and increased admission TnI levels were predictive for in-hospital mortality.
Conclusion: The commonly available biochemical and ECG criteria allow risk stratification of patients with a suspected acute ischemic event. The data analysis can easily be automated and is independent of patient delay.