Observations on Changes in Form of the Initial Ventricular Complex in Isolated Derivations of the Human Electrocardiogram

The literature of recent years has contained numerous contributions dealing with abnormalities of the initial ventricular complex Q R S of the electrocardiogram. Most authors,1however, have dealt largely with changes affecting all derivations consisting of abnormalities in complex contour or increase in the complex base width exceeding the recognized normal.2 Differences of opinion exist as to the cardiac disorder responsible for these deviations from the normal. Most observers, I believe, recongnize myocardial changes affecting the ventricular conduction system, locally or diffusely. Robinson3takes issue with the majority, and emphasizes the rôle of functional myocardial fatigue. He presents electrocardiograms of a patient in which the aberrant complexes approach normal, yet do not attain normal after digitalis and rest. I have not had the opportunity of observing the abnormal complexes return to normal when all three derivations have been affected. In a previous article4I called attention to the high mortality