THE EFFECT OF DIGITALIS ON THE NORMAL ELECTROCARDIOGRAM BY

With the advent of newer leads to the electrocardiogram it has become necessary to repeat the observations that have been made in the past on the cardiographic changes following digitalis administration in healthy subjects. The main object of this work has been to determine the lead or leads most susceptible to the effects of digitalis as well as the design of the deformity produced in the tracing. The need for the investigation has arisen from the common practice of giving digitalis to a patient considered to have heart disease before the electrocardiogram is recorded as part of a special examination. Confusion in diagnosis is specially likely if chest pain is included among the symptoms-a circumstance that allots more than ordinary importance to changes in the electrocardiogram. Methods. The dosage of digitalis leaf was that customarily used in the continuous treatment of a patient needing it. It was, therefore, given in the first place as 2 grains (0-13 g.) daily and later increased to 3 grains (0-2 g.) daily. Rapid digitalization was not followed. Thirteen healthy medical students volunteered to take digitalis during a period of six to eight weeks when the total dosage was from 104 to 135 grains (6 9-9 g.). Digitalis was dispensed to each student when he attended the Cardiac Department to ensure accuracy in regard to the amount taken. A preliminary electrocardiogram was taken before th