Triage of Patients with Acute Chest Pain and Possible Cardiac Ischemia: The Elusive Search for Diagnostic Perfection

View larger version (102K): [in this window] [in a new window]   Figure 1. Electrocardiograms (ECGs) obtained at presentation and a previous comparison tracing.Top. The ECG shows tracing obtained at initial presentation (and obtained during an episode of chest pain) at half-standard scale. Bottom. The ECG shows tracing at standard scale from several years before the current presentation. It was available for comparison at the time of presentation, although the difference in ECG standardization was not noted at that time despite the presence of standardization marks. Subsequent recognition of this difference between the 2 tracings presumably contributed to the cardiologist's interpretation of the new ECG as abnormal, with new J-point depression anterolaterally (V2 to V5).

View larger version (20K): [in this window] [in a new window]   Figure 2. Receiver-operating characteristic curve of the initial electrocardiographic interpretation. The cumulative sensitivity (number of patients with myocardial infarction [MI] divided by all patients with MI) of electrocardiographic interpretations is on the y-axis and is plotted against the cumulative false-positive rate (number of patients without MI divided by all patients without MI) on the x-axis. New is defined as not known to be old. Reproduced from Rouan et al. (13).