Spatial Vector Changes during Ventricular Depolarisation using a Semi‐Orthogonal Lead System—A Study of 190 Cases

Abstract

The paper describes the spatial vector changes during ventricular depolarisation in 190 horses using a semi-orthogonal ECG lead system. The replacement of planar vector loops by a plot of 3 parameters to depict the changing spatial vector, with a time base on the X axis, is described and illustrated. Some horses with diastolic murmurs and some with a history of respiratory problems formed 2 distinct groups. As a result of these findings a possible relationship between the vector changes and the anatomical siting of the ventricles is suggested and discussed. Attention is drawn to certain measurements which appear to have possible use in assessing the significance of cardiac electrical activity in relation to changes in the ventricular myocardium.