6.3 Signals of the Cardiovascular System

|

245

Fig. 6.18: Central reference point according to Wilson – here the mean value of all measured

voltages is formed. The respective measurement is carried out with high impedance via the 5-kΩ-

resistors [83, 85]. The left figure shows the actual measurement and the right figure the equivalent

location in the body.

and Equation 6.8:

VI = R ⋅(IR −IL) = VR −VL

VII = R ⋅(IR −IF) = VR −VF = 2VR + VL

VIII = R ⋅(IL −IF) = VL −VF = 2VL + VR

(6.9)

and further:

VR = (VI + VII)/3

VL = (VIII −VI)/3

VF = −VL −VR = −(VII + VIII)/3 .

(6.10)

Goldberger Leads

The unipolar voltages VL, VR and VF with the central recording point according to

Einthoven are smaller than the voltages VI, VII and VIII of the bipolar derivatives ac-

cording to Einthoven. Therefore Goldberger [21, 22] proposed another reference point

by which, using the same measuring points , the larger measuring voltages aVL, aVR

and aVF arise. ⁹. Here the measured voltages aVL, aVR and aVF are not formed on the

central potential according to Wilson by averaging, but are related to the potential at a

9 The subscript a before the designations of the stresses stands for augmented, which means aug-

mentation.