[Vectorcardiographic examiniations in the syndrome of Wolff-Parkinson-White (author's transl)].

In 37 cases of WPW-syndrome the delta and the 10 msec instantaneous vectors of the QRS and the ST and T vectors were determined by a triaxicardiometer (TMC) analogue computer. The Descartes' coordinates were calculated from the polarcoordinates by the application of circular functions and the 12 conventional leads were numerically and graphically reconstructed from them by coeffificients. In the case of WPW-syndrome the chambers are activated partly by the ventricular pre-excitation, partly by the normally generated and conducted impulse. The delta vector is formed by the pre-excitation, it is oriented toward the right posterior superior, the right posterior inferior and the right anterior superior spatial octants. The early ventricular depolarization is spreading on a myogenic way, when reaching the conduction system, it is partially activated. Related to the ventricular pre-excitation the normally generated and conducted impulses have a delay. This "phasic aberrant conduction" is the cause of a "fusion beat" or functional block. If the pre-excitation, spreading on myogenic way reaches one fascicle, a bifascicular block-like WPW-syndrome is resulted. If the early ventricular excitation penetrates two fascicles, a monofascicular block-like WPW-syndrome is developed. If the early excitation of the three fascicles or of the bundle of His takes place by the activation of the James bundle, delta-wave is not generated, the ventricular depolarization remains normal (LGL-syndrome), but in such a case the normally conducted sinus impulses are also delayed.