The vectorcardiogram of malnourished children during the first months of life

The vectorcardiograms of malnourishedinfants were found to be different from those of normal infants. In the latter group, clockwise QRS loops in the horizontal plane were present from birth to the twenty-fifth day of life, and transitional (or figure-of-8 loops) from the twenty-sixth to the thirty-sixth day. Thereafter anticlockwise loops, representing the usual infantile pattern, appeared. The orientation of the repolarization complexes was very anterior for the first 24 or 48 days (yielding positive T waves in V₁), but later it changed to a posterior position (-15° to -90°) throughout the period of time under study. On the contrary, in the abnormal group it was noted that clockwise loops were related not only to age, but also to weight. That is, on the average, infants with the lower weight showed a persistence of that morphology beyond the usual age; a phenomenon probably due to a delayed progression of the usual left-to-right ventricular ratio in malnourished children. Finally, it was clear that T looplocation was not related to age or weight, thus representing primary changes in repolarization. Although the most anteriorly placed ones were occasionally seen after the administration of intravenous solutions (sometimes containing potassium salts), their presence in cases displaying definite plasma and electrical signs of hypokalemia favors the assumption that potassium changes, per se, were not responsible for these abnormalities. However, they are not necessarily due to right ventricular hypertension as previously considered.