[AVOID COMMON MISTAKES IN REALIZATION OF A ELECTROCARDIOGRAM].

Introduction: The electrocardiogram (ECG) is a noninvasive technique to perform simple, economical, reproducible and provides valuable information that can be used to make the diagnosis of the patient and to guide clinical decisions. It is a diagnostic test used frequently as it can be done quickly, since it is done with a laptop and generally is always possible implementation in any field either primary care, specialty outpatient care. The diagnosis made by the ECG is considered valid in clinical practice, but is only effective if the electrodes are placed in the correct anatomical locations, if the hoses are properly attached to the electrodes, the registry maintains a good quality (the filters are used appropriate, interference and electrical noise are avoided) and ECG compares made by the same registration system (ECG 5 or 10 lead) for determining evolutionary changes (to determine changes in the ST segment during myocardial ischemia or assess the changes caused by reperfusion therapies).

Objective: To review the most common errors in electrocardiography, which are related to inappropriate placements of shunts, cross or exchange of patch cords limb leads, records of poor quality and comparisons of ECG serials made with different acquisition systems (10 vs 5 lead).

Conclusions: We make the recommendations to prevent and avoid these scams that can lead to diagnosis and treatment with adverse outcomes for the patient.