I read with interest the editorial by Kaul and Abbott [1] on evaluation of chest pain in the emergency department. Although the authors made several valuable recommendations on the assessment of acute chest pain in patients in the emergency department, they did not mention one simple and important aid in the decision-making process—the availability of a previously obtained electrocardiogram.

If a patient with chest pain comes to the emergency department and has abnormal electrocardiographic findings (for example, Q waves, ST-segment changes, left bundle-branch block, premature ventricular contractions, or atrial fibrillation), no physician can determine from one isolated electrocardiogram whether the abnormalities are old or new. Therefore, these patients are generally admitted for observation until serial electrocardiograms determine whether these changes are preexistent. Today, with the availability of facsimile machines in every hospital, it is easy to contact the patient's primary physician or the record department of the patient's hospital, especially during the weekend or the evening, to secure a copy of the previous electrocardiogram for comparison.

Thus, the instant availability of a previous electrocardiogram is of great value to a physician in the emergency department in assessing a patient with acute chest pain [2]. To ensure that my patients have this advantage, I routinely give them a copy of their abnormal (or latest) electrocardiographic tracings. For patients who prefer to have the copy with them at all times, the tracing can be reduced and laminated with plastic. This approach makes the electrocardiogram as simple to carry as a credit card [3]. I also give my young patients copies of any electrocardiographic tracings showing early repolarization changes or juvenile patterns, either of which may arouse suspicion in physicians unfamiliar with these normal variants.

The importance of availability of a previous electrocardiogram in the evaluation of patients with acute chest pain in the emergency department, particularly when the current tracing shows changes consistent with ischemia or infarction, has been emphasized by Lee and associates [4]. In a subset of 2024 patients whose current tracings were abnormal, those without myocardial infarction were more than twice as likely to be dismissed (26% compared with 12%) if a previous tracing was available and about 1.5 times as likely to avoid admission to a coronary care unit (39% compared with 27%).