Over decades of overreading a large number of computerized electrocardiogram (ECG) interpretations, we encountered software errors that seemed to be repetitive and consistent despite using different recording systems and interpretation algorithms. The following is an arbitrary collection of common mistakes with important clinical implications. In each case we offer explanations on the likely causes of the computer errors, and offer pointers how to recognize and correct them. In addition to the illustrations in print, an online supplement (OS) provides more examples of the discussed phenomena. In each ECG, original computer interpretations were enlarged for legibility.

There are several well-described disorders that can mimic ST-elevation myocardial infarction (STEMI) in the ECG. These include pericarditis, myocarditis, Prinzmetal angina, stress cardiomyopathy and hyperkalemia [1,2]. In the first of three mini-reviews, we present and discuss a few situations when it was not the clinical condition, but the ECG interpretation software that mistakenly indicated MI. In addition to the scenarios covered in this review, there are other circumstances where the computer can falsely indicate STEMI including early repolarization, the spiked helmet sign, type II Brugada pattern and atypical left bundle branch block that is not recognized by the software as such.