80

|

3 Fundamentals of the Formation of Biosignals

Fig. 3.25: Decoupled oscillations of the sine and AV node according to Figure 3.23 and Figure 3.24

mit kSA−AV = kAV−AV = 1, eSA = 12 und eAV = 7.

time t / s

U / mV

AV-node

Fig. 3.26: Synchronised oscillations of the sine node according to Figure 3.23 and Figure 3.24 with

stronger coupling of the sinus node to the AV node, where the natural frequencies do not differ that

much (kSA−AV = 12, kAV−AV = 1, eSA = 12 and eAV = 9).

Couplings of SA-node, AV-node and HP-complex

With the two oscillators mentioned in the previous section, which describe the coup-

ling of the sinus node with the AV node, many properties of the generation of oscil-

lations in the heart can already be explained. However, the signals obtained in this

way do not resemble those measured at the body surface in the form of an ECG signal

xEKG(t). It is important to note that the His bundle and the Purkinje fibres also rep-

resent their own oscillator, which affects the ECG signal (see Figure 3.13). The output

signals of the sinus node (SA) xSA(t), the atrioventricular node (AV) xAV(t) and the His-