Use of the Dipole Moment in the Assessment of Left Ventricular Hypertrophy

Abstract

SUMMARYA multi-electrode grid lead system, suited for the measurement of the total outward electromotive force of the heart expressed as a dipole moment, was tested in 64 subjects without heart disease and in 44 patients with left ventricular overload. The normal group showed the maximum dipole moment to the left (L-MDM) to be proportional to body weight, and by inference to left ventricular weight. For the patients with heart disease, the degree of hypertrophy was assessed in terms of LV weight derived from biplane angiocardiograms; for these patients, L-MDM was found to be proportional to LV weight (r = 0.85). The grid allowed for a more accurate assessment of LV weight than parameters obtained from the Frank lead system in the same patients.A substantially improved estimation of LV weight was achieved with both systems when body weight was considered in addition to the electrocardiographic measurements.Among the reasons for the better performance of the grid system are surface potential integration instead of sampling, consideration of individual torso dimensions, and as a result of distributed multiple electrodes, absence of distortion in the local field.

Vectorcardiographic‐Hemodynamic Correlations in Adult Aortic Stenosis

“…Their study indicated that VCG contained somewhat more information regarding left ventricular mass and volume than ECG, but the differences were small. Ellison et al (9) improved prediction of left ventricular weight through the combination of 6 grid lead VCG variables, the correlation coefficient increasing from 0.85 to 0.95. They also used non-linear regression analysis and the number of variables applied was large.…”

Πειραματικαι Παρατηρησεις Επι Του Ηλεκτροκαρδιογραφηματος Κατα Την Ηλεκτρικην Μονωσιν Καρδιας Κυνος

“…** Δεδομένα ληφθέντα εκ της Βιβλιογραφίας. συνθήκαι επί των επιφανειών, αϊ όποϊαι χωρίζουν διαμερίσματα διαφορετικής ηλεκτρικής αντιστάσεως (Bayley και Berry 10 ).Ή διπολική ροπή τής καρδίας ύπελογίσθη επί ανθρώπων βάσει στα θεράς μέσης τιμής τής ειδικής αντιστάσεως του σώματος (Πίναξ II) καί συνεσχετίσθη προς παθολογικάς καταστάσεις (Ellison, καί συν 24. ).…”