A Spatial Vector Analyzer for the Conventional Electrocardiogram

Abstract

Present methods of spatial vector analysis are descriptive rather than quantitative, or require lengthy calculations. With the spatial vector analyzer, the spatial vector is constructed from the conventional electrocardiogram, with only minor modifications of electrocardiographic routine. The method is simple, can be applied to mean and instantaneous vectors, and a quantitative characterization of any vector in terms of a horizontal angle, vertical angle, and magnitude can be obtained in about three minutes. It may be expected that the description of any deflection in simple, quantitative terms will improve the electrocardiographic interpretation by eliminating distortion resulting from the limitation to one (frontal) plane.

Cardiodynamic Studies in the Neonate in Health and in Disease

“…T his m ay be v alu ab le in th e serial s tu d y o f cardiac dy n am ics in several clinical co nditions. T h e n o rm a l v a ria tio n s o f d irectio n an d m ag n itu d e o f th e v ecto rs o f P , Q R S a n d T a t different ages h av e been well estab lish ed (16,17,18,19,20). A lth o u g h in fo rm atio n o f th is n a tu re is av ailab le for th e n ew b o rn th e m odifications b ro u g h t a b o u t b y disease processes h av e n o t b een e v a lu ated .…”

“…T he d irectio n o f th e sam e v ecto rs in th e h o riz o n ta l plane w as expressed in te rm s o f azim u th . T he a z im u th s a n d th e m ag n itu d es o f P , Q R S a n d T vectors in the h o riz o n ta l p lan e w ere d e te rm in e d b y use o f th e c o o rd in ate system of Sim onson (17). D ue to th e sn o rt d u ra tio n o f th e Q R S com plex (usually 0.04 seconds) it was im possible to d ete rm in e a c c u ra tely th e d irectio n and m a g n itu d e o f th e in itia l a n d te rm in a l vectors o f Q R S .…”

“…T h e open angle b etw een th e v ecto rs o f Q R S an d T in th e h e a lth y in fa n t o f th is s tu d y (95° in th e fro n ta l plane and 120° in th e h o rizontal plane) is in m a rk e d c o n tra s t to th e sm all values o f th is angle in h e a lth y children (14,20) an d in h e a lth y ad ults o f v ario u s age groups (16,17,42). A lth o u g h R othfeld (15) rep o rts a sm aller Q R S -T angle in h e a lth y n e o n ates, his re su lts should n o t be co m pared to ours due to differences in m easu rin g th e d irectio n o f th e v e c to r o f Q R S as we h a v e discussed p reviously.…”

Derivation of chest‐lead ECG from limb‐lead using temporal convolutional network in variational mode decomposition domain

“…First, lead I measurement is a favoured method to record ECG with wearable devices. Second, lead I is oriented along the intersection line of the horizontal and frontal planes of the body and therefore, lead I signal can be used to correlate the measurements in these two planes [4].…”

Effect of Chest Configuration on Spatial Mean QRS and T Vectors

“…Spatial mean QRS and T vectors were constructed from scalar leads in the frontal plane and at the 5th intercostal space level, using a mechanical vector analyzer (2). The spatial mean vectors are given in terms of azimuth (H), elevation (V), magnitude (Mag), and spatial angle between QRS and T vectors (dA).…”