Ability of Triage Decision Rules for Rapid Electrocardiogram to Identify Patients With Suspected ST-Elevation Myocardial Infarction

BACKGROUND: : The American College of Cardiology/American Heart Association guidelines for ST-elevation myocardial infarction state that an electrocardiogram (ECG) should be performed on patients with suspected acute coronary syndrome upon presentation to the emergency department (ED) within 10 minutes. OBJECTIVE: : To determine how previously published clinical criteria for obtaining an ECG at ED triage perform in a population of patients receiving emergency cardiac catheterization for suspected myocardial infarction. This rule was originally derived by Graff to identify clinical criteria for obtaining an ECG at triage to rapidly identify patients with acute myocardial infarction. The Graff rule was developed in a setting where lytic therapy was the primary reperfusion strategy. A modification proposed by Glickman adds several more criteria in an effort to capture additional patients. We hypothesized that the Graff rule would identify most patients for whom the cardiac catheterization laboratory (CCL) was activated and that the Glickman rule would capture the remaining patients. METHODS: : Three trained physician reviewers retrospectively applied the Graff decision rule to 430 consecutive patients from a database of emergency CCL activations by ED physicians. The Graff rule recommends that patients between the ages of 30 and 49 years received a rapid ECG if they complained of chest pain and those aged 50 years or older received a rapid ECG when they complained of chest pain, shortness of breath, palpitations, weakness, or syncope. The newly developed Glickman rule, which included nausea and vomiting in patients over the age of 80 years, was applied to the patients where the Graff rule was negative. The triage note or earliest medical contact documentation was used to determine whether the patient's complaints would have resulted in a rapid ECG by the decision rule. Each case was reviewed for acute myocardial infarction as defined by high-grade stenosis on the subsequent emergent cardiac catheterization. A single data collection Microsoft Excel spreadsheet was used, and descriptive statistics were performed in Excel and Stata. RESULTS: : Of the 430 CCL activations, 415 (97%; 95% confidence interval, 95%-99%) were identified by the Graff rule. Of the 12 patients who were not identified by the rule, only 2 more were identified by the Glickman criteria. Among patients with confirmed ST-elevation myocardial infarction (79% of CCL activations), the Graff rule was 98% sensitive (95% confidence interval, 96%-99%). CONCLUSIONS: : The Graff ECG triage rule identified almost all patients for whom the CCL was activated. Modification of the rule as proposed by Glickman added very little to the rule's sensitivity, while increasing the number of ECGs required at triage.