Assessment of the standardized reporting guidelines ECG classification system: The presenting ECG predicts 30-day outcomes

Study objective: Standardized reporting criteria for risk stratification studies of patients with potential acute coronary syndromes have been proposed. We sought to determine whether the categories in the recommended 6-item ECG classification system predict rates of 30-day death, myocardial infarction, and revascularization. Methods: We conducted a prospective cohort study of emergency department (ED) chest pain patients who presented to a tertiary care center during a 32-month period. The treating physician classified all ECGs into defined categories. Patients were followed up for 30 days to determine death, myocardial infarction, and revascularization. Our main outcome was the rate of triple composite endpoint of death, myocardial infarction, or revascularization at 30 days from ED presentation in relation to the ECG classification category. Results: There were 3,814 patients who presented to the ED a total of 4,487 times during the study period. Patients had a mean (+/-SD) age of 51.8+/-15.9 years, were more likely to be women (59%) than men, and were most commonly black (68%). The relationship between initial ECG classification and 30-day outcome was highly significant (P<.001), with event rates ranging from 3.2% to 72.7%, depending on ECG classification category. Conclusion: The ECG classification system that is being recommended in the standardized guidelines predicts 30-day composite rates of death, acute myocardial infarction, and revascularization.