Delta wave changes following attacks of paroxysmal tachycardia in WPW syndrome.

A case of WPW syndrome associated with recurrent attacks of paroxysmal tachycardia for 25 years, is reported. Vectorcardiograms recorded after an attack offered evidence of multiple anomalous pathways between the left atrium and the left ventricle. The high sensibility of the angle recording channels of the triaxicardiometer, i. e. the polar vectors, is considered to represent a factor essential in delta wave analysis.