Orthogonal versus Planar Vector-Electrocardiography

Abstract

The basic elements for quantitation of the three-dimensional electromotive forces generated during the electric cardiac cycle are the spherical coordinates of each instantaneous vector, i.e. its spatial magnitude and its elevation and azimuth angles. Since presently used display systems provide only projections of the spatia vectors, their spherical coordinates have to be computed from these data By using combinations of the projection data provided by the vectorcardiogram (VCG) and/or the orthogonal electrocardiogram (OECG), the determination of a vector’s spherical coordinates was attempted by geometric construction, by algebra and trigonometry and by electronic processing. Geometric constructions on the scalar recording of the ‘corrected’and properly amplified orthogonal leads proved more convenient than the other methods, and eliminated the need for expensive electronic equipment. Since the OECG is also suitable for morphologic interpretation, it could replace both the 12-lead ECG and the VCG in either research or routine practice.

Ventricular Repolarization during Smoking

“…The orthogonal electrocardiogram (OECG) [9] was recorded from 50 individuals in the following three stages: (a) at rest, (b) immediately after moderate exercise, and (c) during smoking of a filter cigarette.…”