The Electrocardiogram and Ventricular Preponderance

Following Elinthoven's¹first description of the characteristic directional changes in the R wave, in lead III, associated with aortic or mitral disease, the applicability of the electrocardiograph to the study of alterations in the size of the heart has been severely questioned. Clinical observers have held widely differing views in regard to the value of the so-called electrocardiographic signs of hypertrophy. That there are many cases in which the electrocardiograms do not agree with the clinical evidence has been recognized. Bridgeman²has called attention to the fact that in general the English and American observers have accepted the electrocardiographic evidences of hypertrophy, while the German authors placed but little reliance on these findings. Classification of this mass of conflicting evidence began with the calculation of the direction of the electrical axis of the heart by Einthoven, Fahr, and de Waart.³These authors find that in normal individuals the electrical axis