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6 Applications and Methods in Biosignal Processing

Fig. 6.19: Magnification of the unipolar measurement voltages in the ECG lead according to Gold-

berger [21, 22]: The figure above shows the recording arrangement, the figure below the associated

recording of the voltage vectors.

virtual mass point, which is composed of the average of the other potentials as follows:

aVL = VII/2 −VIII

aVR = VIII/2 −VII

aVF = VI/2 −VII .

Figure 6.19 shows how the associated voltage vector increases by approximately 30 %.

Wilson Leads

In the Wilson ECG leads, the heart vector is measured in the horizontal plane. In

this cross-section, it is sometimes easier to detect various heart diseases (e.g. special

myocardial infarction) than in the frontal plane, because the electrodes are closer to

the heart than in the Einthoven or Goldberger leads. As already shown in Figure 6.16,

six electrodes (V1 to V6) are placed in the same upper body plane, at the level of the

4th and 5th rib from the top (see Figure 6.20).