Frequency of Electrocardiographic Recordings in Patients Presenting With Angina Pectoris (from the Investigation of National Coronary Disease Identification)

The appropriate progression of diagnostic testing for acute angina has been the topic of several recommendations by the American College of Cardiology and American Heart Association (ACC/AHA). We measured how frequently electrocardiography (ECG) is provided as the initial cardiac diagnostic test, as recommended for patients with new angina. Using an insurance database representing 2% of the U.S. adult population, we identified patients undergoing a new cardiac diagnostic process for angina. Rates of initial ECG were stratified by age, gender, co-morbid disease, and care setting. Of 4.4 million patients, 18,139 met the entry criteria by presenting with anginal symptoms for testing. A substantial portion (35%, 95% confidence interval [CI] 34% to 35%) did not receive the initial ECG recommended by expert guidelines. Patients treated in emergency departments received an initial ECG more frequently (91%, CI 90% to 92%) than patients tested in outpatient settings (61%, CI 60% to 62%; risk ratio [RR] 0.67, CI for RR 0.65 to 0.68) or in inpatient hospital settings (34%, CI 32% to 37%; RR 0.38, CI for RR 0.36 to 0.40). Slightly lower rates of initial ECG were observed in men (RR 0.93 vs women, CI for RR 0.91 to 0.95) and patients over 64 years (RR 0.93 vs younger patients, CI for RR 0.91 to 0.95). Total diagnostic costs averaged $954 when testing began with the recommended ECG versus $1,233 when testing did not. In conclusion, ECG is not universally obtained as the initial test for patients presenting with anginal symptoms despite evidence-based recommendations for such use. Clinicians should be aware that suboptimal use of ECG in certain settings may hinder investigations of heart disease.