抄録
For the elucidation of some characteristics of normal vectorcardiogram, the statistical analysis of instantaneous QRS vectors and analyticogeometrical analysis of vector-cardiogram were carried out in the strictly defined normal subjects, using the FRANK lead system. Results showed that spatial QRS loops were essentially two-dimensional and that the plane representing the spatial QRS loop was given by "plane-345" in the normal vectorcardiogram. Once the planarity of spatial QRS loop was proved, it was possible to think of spatial QRS plane represented by the plane-345. Some characteristics of normal vectorcardiogram were discussed in the light of rotation of spatial QRS plane.
