Question

Explain a 12 lead ecg system with the detailed representation of all leads and how they are formed

Answer 1

Frank’s Lead System

The further development of lead systems has resulted in the classic 12 leads of today.

The focus was less on understanding the workings of the electrophysiology of the heart, but more on the phenomenological view of the heart’s electrical activity outside the body. In 1956 Frank described the heart as a rotating dipole within space. In principle, a rotating dipole is like a battery with a positive and negative pole spinning in space. Frank asked himself how this rotating dipole could most effectively be measured and described. He placed the electrodes on the body so that the measured leads X, Y and Z (see image 10) were placed in a row, thereby making a Cartesian coordinate system. This results in a representation in the form of a so-called vector loop. This corresponds to a 3D representation of the rotating heart’s dipole in space.