12-lead Holter electrocardiography. Review of the literature and clinical application update.

This brief review is focused on 12-lead Holter electrocardiogram (ECG) recording including a review of the literature and the description of the advantages of its application. The standard 12-lead ECG provides a bedside snapshot of the electrical activity of the heart including vector information, but a snapshot of a few beats for some seconds might miss the whole story. Traditional Holter ECG displaying two or three leads may record all heart beats during a prolonged period, but the limited vector information might be a cause of shortcomings in the ECG diagnosis. The 12-lead Holter ECG overcomes these disadvantages and should be preferred for detecting episodes of arrhythmias, localize their origin or the localization of myocardial ischemia. The 12-lead Holter ECG monitoring is efficient in the evaluation of the effect of drugs or interventional therapeutic procedures, i.e., efficiency of biventricular pacing in patients with heart failure and permanent atrial fibrillation (AF). The automatic analysis of parameters in 12-lead Holter ECG is also providing information for risk stratification. In order to obtain a precise diagnosis based on the criteria established on standard ECG, the "real" 12-lead ECG with ten electrodes is advocated.