[Electrical positions of the heart and its variants in orthogonal electrocardiographic systems]

In a total of 151 healthy subjects the changes in the orthogonal electrocardiographic systems of Frank, McFee, SVEC III and Akulinicev were followed up, in the groups with vertical indifferent and horizontal positions, grouped into three age subgroups and according to age. They were compared with the general groups of the corresponding age and sex. It was established that at the age from 20 to 29, the changes with the systems of Frank, McFee and SVEC III were in RY, in both sexes that index, at vertical position, was increased versus the general group; at indifferent position the same index showed a reduction in males. Akulinicev system revealed changes of SX (increase) and SY (decrease) only at vertical position and only in females. At the age from 30 to 44 the vertical position in both sexes revealed changes only in RY (increase) with Frank, McFee and SVEC III, whereas the horizontal position revealed a decrease of the same index. At the age from 45 to 60 years, changes in some of the systems were established only at the horizontal position--increase of RX mainly in males and with some systems in females--reduction of RY. The statistically significant changes in the individual indices at the various positions subgroups are discussed as well as the possibilities of their differentiation from pathological states (left- and right-ventricular hypertrophy).