Vectorcardiographs and electrocardiographic examinations were made inMZ and DZ twins, triplets and quadruplets. The similarity of the cardiac electrogenesis in the twins was studied using the correlation calculation after the affinic transformation of the vectorcardiograms and the multipolar description of cardioelectric field. The similarity of electrocardiograms and vectorcardiograms in MZ twins depends on heart electrogenesis.

The differences appearing during the neonatal period result from a nonuniform course of circulation organ adaptation and the establishment of conduction pathways in the newborn heart.