Comparative study of three vectorcardiographic lead systems.

A homogeneous model of rabbit torso and physical dipole are used. A comparison is made between the corrected orthogonal vectorcardiographic lead systems after Frank, McFee-Parungao and Zao. The components X, Y, Z of the lead vectors are measured for 15 points which can be inserted in the cardiac volume under normal conditions. The modules of the lead vectors and the angles between them are calculated. The three vectorcardiographic systems are compared with respect to the ratio between the modules (X:Y:Z) and the deviations of the angles from the real value. Best orthogonality are found with the system after Frank, if the thoracic electrodes are placed precisely at the level of the so-called electrical cardiac centre. No essential differences are found between the systems after Frank and after McFee-Parungao with respect to correctedness and orthogonality.