Cardioelectric field on the body surface of pig during initial and final ventricular activity

The cardioelectric field on the body surface of three-month-old pigs has been studied during ventricular depolarization and repolarization by the method of electrocardiotopography. The results indicated that during ventricular depolarization the electric field on the body surface in pig is formed before the begin- ning of the ascending part of the R-wave relative to the SII-peak with the cranial location of areas of positive cardiopotentials and with the caudal location of areas of negative cardiopotentials. The first inversion of areas of positive and negative cardioelectric potentials occurs during the period of the descending part of the R -wave, the second inversion of cardiopotentials begins on the ascending part of the S -wave. During ventricular repolarization the zone of negative cardiopotentials occupies ventral and dorsal sides of the body surface; the zone of a positive potential is situated medially on the ventral part of the thorax. The zones of positive and negative cardiopotentials do not change their position during the whole period of repolarization.Interspecific differences (sheep, dog) are shown in the distribution of cardioelectric potentials on animals' body surface during ventricular depolarization and repolarization.