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# Table 3 Application of the inverse-square law to the simulation of potentials measured between two opposite ECG lectrodes

Potential “UP” electrode LV wall Septum RV wall “DOWN” electrode
The refferent “isoelectric” potential of the P-R segment Electric field sources Mass (M) 1.0 0.9 0.7 Distance between electrodes: 1.5 + 0.3 + 0.2 + 1.7 = 3.7
Potential (P) 50.0 50.0 50.0
Distance (Du) from the “UP” electrode 1.5 1.8 2.0
Calculated potentials (M × P)/(Du × Du) 22.2 13.9 8.8
The P-R potential: 44.9-34.9 = + 10 2.2 1.9 1.7 Distance (Dd) from the “DOWN” electrode
10.3 12.5 12.1 Calculated potentials (M × P)/(Dd × Dd)
Total potential on the “UP” electrode 44.9   34.9 Total potential on the “DOWN” electrode
Normal early QRS potential relative to the P-R potential: DOWN deflection makes a Q wave Electric field sources Mass (M) 1.0 0.9 0.7
Potential (P) 50.0 -10.0 50.0
Distance (Du) from the “UP” electrode 1.5 1.8 2.0
Calculated potentials (M × P)/(Du × Du) 22.2 -2.8 8.8
The absolute potential: 28.2-19.9 = +8.3 2.2 1.9 1.7 Distance (Dd) from the “DOWN” electrode
Relative to the P-R potential: 8.3-10 = -1.7 10.3 -2.5 12.1 Calculated potentials (M × P)/(Dd × Dd)
Total potential on the “UP” electrode 28.2   19.9 Total potential on the “DOWN” electrode
Negative potential of the “coronary” Q wave. due to reduced potential of the LV wall Electric field sources Mass (M) 1.0 0.9 0.7
Potential (P) 10.0 -10.0 50.0
Distance (Du) from the “UP” electrode 1.5 1.8 2.0
Calculated potentials (M × P)/(Du × Du) 4.4 -2.8 8.8
The absolute potential: 10.4-11.7 = -1.3 2.2 1.9 1.7 Distance (Dd) from the “DOWN” electrode
Relative to the P-R potential: -1.3-10 = -11.3 2.1 -2.5 12.1 Calculated potentials (M × P)/(Dd × Dd)
Total potential on the “UP” electrode 10.4   11.7 Total potential on the “DOWN” electrode
1. All unitsa are arbitrary (distance between electrodes is 3.7 units, potential of well repolarised heart muscle is +50 units, potential of ischemic is reduced to positive values <50, while the depolarised muscle is -10 units). The referent “isoelectric P-R segment” is used to explain small, normal Q waves that happen due to early depolarization of the septal muscle. Profound “corronary Q waves” develop due to reduced positive potential of the LV wall caused by only partial repolarization. 