Anterior chest lead: right sternum V 1 (red), left sternum V2 (yellow) flat V 1, V4 (brown) intersection of left clavicle midline and 5th intercostal, midpoint V3 (green) between V2 and V4, intersection of V5 (black) horizontal line V4 and axillary front line, and V6 (purple) flat V4 and V4.
Extended data:
Different wires are formed between the two electrodes or between the electrodes and the central potential terminal, which are connected with the positive and negative electrodes of the galvanometer of the electrocardiograph to record the electrical activity of the heart. A bipolar wire is formed between two electrodes, one of which is a positive electrode and the other is a negative electrode.
Bipolar limb leads include leads ⅰ, ⅱ and ⅲ; A monopole wire is formed between the electrode and the center potential terminal. At this time, the detection electrode is positive and the central potential terminal is negative. AvR, avL, avF, V 1, V2, V3, V4, V5 and V6 are all unipolar leads.
Because avR, avL and avF are far away from the heart, the potential difference recorded when the central electrode is taken as the negative electrode is too small, so the negative electrode is the average of the sum of the lead potentials of the other two limbs except the probe electrode. Because this recording increases the potential of avR, avL and avF leads, these leads are also called pressurized unipolar limb leads.
References:
Electrocardiogram Baidu Encyclopedia