A Comparative Analysis of Several Corrected Vectorcardiographic Leads.

DURING the past decade a great deal of attention has been devoted to the development and application of one or more vectorcardiographic lead systems possessing certain highly desirable physical characteristics. The overriding design consideration has been that the lead system provide a truly Cartesian frame of reference for the display of cardiac vectors. Achievement of this goal requires that the axes of the three component leads be mutually orthogonal, that their individual electrocardiographic sensing abilities be equally scaled, and that both of the preceding properties remain essentially invariant throughout the cardiac region. Sets of electrocardiographic connections that attempt to satisfy these basic requirements are frequently referred to as corrected lead systems. They appear to be gaining increasing acceptance in vectorcardiographic practice. The ultimate test of a vectorcardiographic system lies in the demonstration of its reliability as a clinical diagnostic tool. Pending such clinical testing and confirmation, however, the special merits of corrected lead systems are predicated on their adherence to the specific design principles referred to above. Therefore it is of interest to examine the physical properties of such leads in detail and to determine how closely their parameters approximate the ideal situation. There is nothing basically new in the idea of exploring the physical properties of lead connections. Indeed, it was in this way that the