An electrocardiogram (ECG) is a simple method used to analyze the electrical activity of the heart. It is clinically useful because it is immediately available, non-invasive and inexpensive. The analysis of this graphic record can provide valuable information on heart function and lead to the diagnosis of specific cardiovascular disorders; e.g. it can be used to detect heart rate or cardiac conduction disorders, myocardial ischemia and other heart diseases. Also, it may reveal other findings such as metabolic changes which on occasion can be life-threatening such as hyperpotassemia.
Atrial fibrillation is the most common arrhythmia. Its frequency of presentation increases with age. It is a common reason for hospitalization as a cause of decompensation of heart failure or a thromboembolic event.
This atlas describes, in the first place, the particular characteristics of a normal ECG, and secondly, the main features observed on this record in the presence of disease, e.g. cardiac conduction disorders, arrhythmia, including atrial fibrillation, cardiac hypertrophy, coronary artery disease, and electrolytic disorders.
